Changchun, China
Changchun, China

Jilin University is a leading national research university under the direct jurisdiction of China's Ministry of Education.Located in Changchun, the capital city of Jilin Province in Northeast China, the university has seven campuses in six districts which are home to thirty-nine colleges covering thirteen academic disciplines, including philosophy, international relations, economics, law, literature, education, history, science, engineering, agriculture, medicine, management, and military science. The University has thirteen disciplinary areas, six national key laboratories, and seven national bases for the development of basic science. Other resources include five research bases for humanities and social science, eleven key laboratories sponsored by the Ministry of Education and eleven by other ministries of Chinese government.Jilin University is one of the most prestigious "Top 10" universities in China, and has several research projects in automobile engineering, chemistry, computer science, electrical engineering and biology. JLU also provides undergraduate and graduate programs in law, literature, philosophy, medicine and veterinary science. It is one of the key universities involved in China's Project 985, Project 211 and Project 2011.Jilin University is a comprehensive and national key university. JLU offers a variety of degree programs. It has now 115 undergraduate programs, 192 Master's degree program, 105 doctoral degree programs, and seventeen post-doctoral programs. In 2003 the university enrolled 59,000 full-time students, including more than 10,000 graduate students. At present there are 6,540 faculty members, with twenty members of Chinese Academy of science and Chinese Academy of Engineering, 1270 full professors, and 1652 associate professors. Wikipedia.

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The present invention provides an adulterated peanut oil detector and an adulterated peanut oil detection method, and pertains to the technical domain of product analysis. The detector comprises a casing, a LCD and Return key, Enter key, Up key, Down key, a power switch, a power socket, and a USB interface arranged on the casing, and a microprocessor and a power supply unit mounted in the casing and electrically connected to the components on the casing, wherein, a module cover is arranged on the top surface of the casing, and a pretreatment module and a detection module are mounted in the space under the module cover. The pretreatment module comprises a heating body and cuvette slots, and the detection module comprises an axial fan, a radiating plate, a refrigerating plate, and cuvette slots. The detection method comprises sample preheating procedure and slow refrigeration procedure. The detector and method provided in the present invention can quickly and easily detect whether the peanut oil sample is adulterated and the percentage of adulteration, and is applicable to quick on-spot detection of rapeseed oil, sunflower oil, maize oil, cotton oil, palm oil, and soybean oil, etc. admixed in peanut oil.

The present invention provides an adulterated peanut oil detector and an adulterated peanut oil detection method, and pertains to the technical domain of product analysis. The detector comprises a casing, a LCD and Return key, Enter key, Up key, Down key, a power switch, a power socket, and a USB interface arranged on the casing, and a microprocessor and a power supply unit mounted in the casing and electrically connected to the components on the casing, wherein, a module cover is arranged on the top surface of the casing, and a pretreatment module and a detection module are mounted in the space under the module cover. The pretreatment module comprises a heating body and cuvette slots, and the detection module comprises an axial fan, a radiating plate, a refrigerating plate, and cuvette slots. The detection method comprises sample preheating procedure and slow refrigeration procedure. The detector and method provided in the present invention can quickly and easily detect whether the peanut oil sample is adulterated and the percentage of adulteration, and is applicable to quick on-spot detection of rapeseed oil, sunflower oil, maize oil, cotton oil, palm oil, and soybean oil, etc. admixed in peanut oil.

Zheng K.,Jilin University | Song W.,Jilin University | He G.,Jilin University | Yuan Z.,University of Macau | Qin W.,Jilin University
Optics Express | Year: 2015

Under 980 nm excitation, the temperature dependence of fivephoton UV (256 and 276 nm) upconversion luminescence in Yb3+-Er3+ codoped β4-NaLuF4 nanocrystals was studied from 303 K to 523 K. The 4D7/2 and 4G9/2 levels of Er3+ are confirmed to be thermally coupled levels. They are the highest energy states for optical thermometry known so far. By using fluorescence intensity ratio technique, optical temperature sensing characteristics based on the 4D7/2/4G9/24I15/2 transitions of Er3+ were reported here for the first time. The obtained sensitivity of this UV-based sensor is higher than that of green-based optical thermometer in low temperature range. © 2015 OSA.

Li Q.-L.,Jilin University | Gu W.-X.,Tianjin University of Technology | Gao H.,Tianjin University of Technology | Yang Y.-W.,Jilin University | Yang Y.-W.,Nanjing University
Chemical Communications | Year: 2014

In this feature article, we give an overview of the preparation and application of self-assembled architectures based on an emerging area of polymers, i.e., poly(glycidyl methacrylate)s (PGMAs) and their derivatives. A series of PGMA-based aggregates and hybrids, such as micelles, reverse micelles, capsules, nanoparticles, and inorganic-organic hybrid materials, has been constructed, and diverse morphologies were formed, driven by hydrophobic interactions, hydrogen bonding, ionic complexation, host-guest interactions, etc. In particular, the assemblies have shown great potential applications as drug vectors, gene vectors, solubilizing agents, antimicrobial agent, and so forth. Herein, the general guidelines are elaborately selected from literature examples and partially from our own. Although still in its infancy, self-assembly of PGMA-based polymers is expected to become a hot topic in polymer chemistry and materials science. © 2014 the Partner Organisations.

Alia S.M.,University of California at Riverside | Zhang G.,Jilin University | Kisailus D.,University of California at Riverside | Li D.,University of California at Riverside | And 3 more authors.
Advanced Functional Materials | Year: 2010

Porous platinum nanotubes (PtNTs) with a all thickness of 5 nm, an outer diameter of 60 nm, and a length of 520 μm are synthesized by galvanic displacement with silver nanowires, which are formed by the ethylene glycol reduction of silver nitrate. Oxygen reduction reaction (ORR) and durability experiments are conducted for PtNTs, Pt nanoparticles supported on carbon (Pt/C), and bulk polycrystalline Pt (BP-Pt) electrocatalysts to evaluate their catalytic properties for use as cathode catalysts in proton exchange membrane fuel cells. PtNTs demonstrate improved mass and specific activity for ORR and durability to Pt/C. Following durability testing, PtNTs exhibit specific ORR activity approaching that of BP-Pt. Catalyst activity for the methanol oxidation reaction (MOR) is characterized through cyclic voltammetry and chronoamperometry techniques to evaluate the materials for use as anode catalysts in direct methanol fuel cells. The PtNTs show improved specific activity for MOR and chronoamperometry characteristics over Pt/C and BP-Pt catalysts. This study focuses on the use of porous platinum nanotubes (PtNTs) with a thickness of 5 nm, an outer diameter of 60 nm, and a length of 520 μm as fuel cell catalysts. PtNTs demonstrate higher mass and specific activity for oxygen reduction and durability than the conventional platinum supported on carbon catalyst (Pt/C). PtNTs further illustrate greater specific activity and poison resistance for methanol oxidation than Pt/C and bulk platinum. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Shi N.-Q.,Jilin Medical College | Shi N.-Q.,Peking University | Qi X.-R.,Peking University | Xiang B.,Peking University | And 3 more authors.
Journal of Controlled Release | Year: 2014

Cell-penetrating peptides (CPPs), often vividly termed as the "Trojan Horse" peptides, have attracted considerable interest for the intracellular delivery of a wide range of cargoes, such as small molecules, peptides, proteins, nucleic acids, contrast agents, nanocarriers and so on. Some preclinical and clinical developments of CPP conjugates demonstrate their promise as therapeutic agents for drug discovery. There is increasing evidence to suggest that CPPs have the potential to cross several bio-barriers (e.g., blood-brain barriers, intestinal mucosa, nasal mucosa and skin barriers). Despite revolutionary process in many aspects, there are a lot of basic issues unclear for these entities, such as internalization mechanisms, translocation efficiency, translocation kinetics, metabolic degradation, toxicity, side effect, distribution and non-specificity. Among them, non-specificity remains a major drawback for the in vivo application of CPPs in the targeted delivery of cargoes. So far, diverse organelle-specific CPPs or controlled delivery strategies have emerged and improved their specificity. In this review, we will look at the opportunities of CPPs in clinical development, bio-barriers penetration and nanocarriers delivery. Then, a series of basic problems of CPPs will be discussed. Finally, this paper will highlight the use of various controlled strategies in the organelle-specific delivery and targeted delivery of CPPs. The purpose of this review will be to emphasize most influential advance in this field and present a fundamental understanding for challenges and utilizations of CPPs. This will accelerate their translation as efficient vectors from the in vitro setting into the clinic arena, and retrieve the entry art to "Troy". © 2014 Elsevier B.V.

Han C.,Heilongjiang University | Zhang Z.,Jilin University | Xu H.,Heilongjiang University | Li J.,Heilongjiang University | And 4 more authors.
Angewandte Chemie - International Edition | Year: 2012

A series of dibenzofuran-based ternary hosts were designed and prepared. The singlet energy levels and carrier injecting/transporting abilities were adjusted on the basis of the mixed meso and short-axis linkages (see picture). By harmonizing the optical and electrical properties, the blue-emitting diodes realized highly efficient blue electrophosphorescence with ultralow driving voltages. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chen C.,Jilin University | Song M.,University of Toledo | Xin C.,Old Dominion University | Backens J.,Christopher Newport University
IEEE Network | Year: 2013

Cognitive radio networks are a promising solution to the spectrum scarcity issue. However, cognitive radio networks are vulnerable to various kinds of security attacks, among which the jamming attack has attracted great attention as it can significantly degrade spectrum utilization. In this article we model the jamming and anti-jamming process as a Markov decision process. With this approach, secondary users are able to avoid the jamming attack launched by external attackers and therefore maximize the payoff function. We first use a policy iteration method to solve the problem. However, this approach is computationally intensive. To decrease the computation complexity, Q-function is used as an alternate method. Furthermore, we propose an algorithm to solve the Q-function. The simulation results indicate that our approach can achieve better performance than existing approaches to defend against the jamming attack. © 1986-2012 IEEE.

Lu Z.,University of California at Riverside | Li C.,University of California at Riverside | Li C.,Jilin University | Yin Y.,University of California at Riverside
Journal of Materials Chemistry | Year: 2011

A convenient route for the preparation of thermochromic VO2 particles has been developed by combining solution-phase hydrolysis and a thermal reduction process. With this method, the particle size can be easily tuned from tens to hundreds of nanometres. The liquid dispersibility of these VO2 particles facilitates convenient observation and effective measurement of the temperature-dependent optical properties in the visible region. We observe a blue shift of the resonance peak of metal-phase VO 2 particles with decreasing size. The size effect also exists in the phase transition behavior: smaller VO2 particles exhibit a wider hysteresis curve during the semiconductor-to-metal transition. We also demonstrate that the VO2 particles in the form of a colloidal dispersion can be easily incorporated into thin plastic thermochromic films that may be used as smart windows for energy management. This journal is © The Royal Society of Chemistry.

Qi W.,Jilin University | Guo Y.,Jilin University
Journal of the American Chemical Society | Year: 2011

Acid-decomposable, luminescent ZnO quantum dots (QDs) have been employed to seal the nanopores of mesoporous silica nanoparticles (MSNs) in order to inhibit premature drug (doxorubicin) release. After internalization into HeLa cells, the ZnO QD lids are rapidly dissolved in the acidic intracellular compartments, and as a result, the loaded drug is released into the cytosol from the MSNs. The ZnO QDs behave as a dual-purpose entity that not only acts as a lid but also has a synergistic antitumor effect on cancer cells. We anticipate that these nanoparticles may prove to be a significant step toward the development of a pH-sensitive drug delivery system that minimizes drug toxicity. © 2011 American Chemical Society.

Alper J.P.,University of California at Berkeley | Wang S.,University of California at Berkeley | Wang S.,Jilin University | Rossi F.,CNR Institute of Materials for Electronics and Magnetism | And 4 more authors.
Nano Letters | Year: 2014

Microsupercapacitors are attractive energy storage devices for integration with autonomous microsensor networks due to their high-power capabilities and robust cycle lifetimes. Here, we demonstrate porous silicon nanowires synthesized via a lithography compatible low-temperature wet etch and encapsulated in an ultrathin graphitic carbon sheath, as electrochemical double layer capacitor electrodes. Specific capacitance values reaching 325 mF cm -2 are achieved, representing the highest specific ECDL capacitance for planar microsupercapacitor electrode materials to date. © 2014 American Chemical Society.

Chen J.,Jilin University | Chen J.,Changchun Normal University | Wang X.,Jilin University | Cui X.,Jilin University | And 2 more authors.
Chemical Communications | Year: 2014

An amorphous metal-free N-doped carbon film prepared by sputtering and annealing exhibits comparable electrocatalytic activity and superior stability and methanol tolerance to the commercial Pt/C catalyst via a four-electron pathway for oxygen reduction reaction (ORR). Pyridinic nitrogen in films plays a key role in electrocatalytic activity for ORR. This journal is © The Royal Society of Chemistry 2014.

Wang L.,Peking University | Wang L.,Jilin University | Du Y.,Key Laboratory of Carcinogenesis and Translational Research | Lu M.,Peking University | Li T.,Peking University
Nucleic Acids Research | Year: 2012

Protein lysine acetylation plays an important role in the normal functioning of cells, including gene expression regulation, protein stability and metabolism regulation. Although large amounts of lysine acetylation sites have been identified via large-scale mass spectrometry or traditional experimental methods, the lysine (K)-acetyl-transferase (KAT) responsible for the acetylation of a given protein or lysine site remains largely unknown due to the experimental limitations of KAT substrate identification. Hence, the in silico prediction of KAT-specific acetylation sites may provide direction for further experiments. In our previous study, we developed the acetylation set enrichment based (ASEB) computer program to predict which KAT-families are responsible for the acetylation of a given protein or lysine site. In this article, we provide KAT-specific acetylation site prediction as a web service. This web server not only provides the online tool and R package for the method in our previous study, but several useful services are also included, such as the integration of protein-protein interaction information to enhance prediction accuracy. This web server can be freely accessed at huac. © 2012 The Author(s).

Liu C.,CAS Institute of Chemistry | Gao Z.,Jilin University | Zeng J.,CAS Institute of Chemistry | Hou Y.,CAS Institute of Chemistry | And 7 more authors.
ACS Nano | Year: 2013

Detection of early malignant tumors remains clinically difficult; developing ultrasensitive imaging agents is therefore highly demanded. Owing to the unusual magnetic and optical properties associated with f-electrons, rare-earth elements are very suitable for creating functional materials potentially useful for tumor imaging. Nanometer-sized particles offer such a platform with which versatile unique properties of the rare-earth elements can be integrated. Yet the development of rare-earth nanoparticle-based tumor probes suitable for imaging tiny tumors in vivo remains difficult, which challenges not only the physical properties of the nanoparticles but also the rationality of the probe design. Here we report new approaches for size control synthesis of magnetic/upconversion fluorescent NaGdF4:Yb,Er nanocrystals and their applications for imaging tiny tumors in vivo. By independently varying F-:Ln3+ and Na+:Ln3+ ratios, the size and shape regulation mechanisms were investigated. By replacing the oleic acid ligand with PEG2000 bearing a maleimide group at one end and two phosphate groups at the other end, PEGylated NaGdF4:Yb,Er nanoparticles with optimized size and upconversion fluorescence were obtained. Accordingly, a dual-modality molecular tumor probe was prepared, as a proof of concept, by covalently attaching antitumor antibody to PEGylated NaGdF4:Yb,Er nanoparticles through a "click" reaction. Systematic investigations on tumor detections, through magnetic resonance imaging and upconversion fluorescence imaging, were carried out to image intraperitoneal tumors and subcutaneous tumors in vivo. Owing to the excellent properties of the molecular probes, tumors smaller than 2 mm was successfully imaged in vivo. In addition, pharmacokinetic studies on differently sized particles were performed to disclose the particle size dependent biodistributions and elimination pathways. © 2013 American Chemical Society.

Xue Y.,Jilin University | Matuszewski M.,Instytut Fizyki Polskiej Akademii Nauk
Physical Review Letters | Year: 2014

We predict the existence of a self-localized solution in a nonresonantly pumped exciton-polariton condensate. The solution has a shape resembling the well-known hyperbolic tangent profile of a dark soliton, but exhibits several distinct features. We find that it performs small oscillations, which are transformed into "soliton explosions" at lower pumping intensities. Moreover, after hundreds or thousands of picoseconds of apparently stable evolution the soliton decays abruptly, which is explained by the acceleration instability found previously in the Bekki-Nozaki hole solutions of the complex Ginzburg-Landau equation. We show that the soliton can be formed spontaneously from a small seed in the polariton field or by using spatial modulation of the pumping profile. © 2014 American Physical Society.

Liang S.,Changchun Normal University | Liang S.,Jilin University | Zhang J.,Nanjing Normal University
Nonlinear Analysis: Real World Applications | Year: 2014

In this paper, we consider the existence and multiplicity of solutions of Kirchhoff type problems with critical nonlinearity in R3:- ε2(a+b∫R3|u|2dx) Δu+V(x)u=K(x)|u|4u+h(x,u), (t,x) â̂̂R×R3. Under suitable assumptions, we prove that this has at least one solution and for any mâ̂̂N, it has at least m pairs of solutions. © 2013 Elsevier Ltd. All rights reserved.

Wei Y.,Jilin University | Yang M.,Zhejiang Normal University
Zeitschrift fur Angewandte Mathematik und Physik | Year: 2014

In this paper, we consider the existence and multiplicity of homoclinic type solutions to a system of diffusion equations with spectrum point zero. By using some recent critical point theorems for strongly indefinite problems, we obtain at least one nontrivial solution and also infinitely many solutions. © 2013 Springer Basel.

Tong X.,China Institute of Technology | Dai M.-J.,China Institute of Technology | Zhang Z.-H.,Jilin University
Applied Surface Science | Year: 2013

In this study, the selective laser surface melting and laser surface alloying technologies were adopted to improve the thermal fatigue resistance of medium carbon hot-work die steel (H13) by a CO2 laser. Two kinds of mixed chromium (Cr) and nickel (Ni) powders were used as the laser alloying materials, and the effects of the mixing ratio on the thermal fatigue resistance were investigated thoroughly. Some important results such as cross-sectional morphology, phases, hardness and thermal fatigue behavior were analyzed and evaluated. It indicates that the laser surface alloying technique using mixed powder with ratio of 75%Cr-25%Ni can considerably enhance the thermal fatigue resistance of the H13 steel. The laser alloyed zone has excellent properties such as preventing crack initiation and oxidation corrosion compared with original H13. Thermal cracking and oxidation corrosion that occurred at substrate surface can be surrounded and intercepted by a gridded laser strengthened structure. Therefore, the naturally developed cracks could be effectively prevented. Theses results and analysis show that laser surface technique can be positively used to improve surface mechanical properties of H13 dies. © 2013 Elsevier B.V.

Niu Y.,Jilin University | Dick A.,University of Adelaide | Brooks M.,University of Adelaide
IEEE Transactions on Image Processing | Year: 2012

This paper proposes the use of an adaptive locally oriented coordinate frame when calculating an optical flow field. The coordinate frame is aligned with the least curvature direction in a local window about each pixel. This has advantages to both fitting the flow field to the image data and in imposing smoothness constraints between neighboring pixels. In terms of fitting, robustness is obtained to a wider variety of image motions due to the extra invariance provided by the coordinate frame. Smoothness constraints are naturally propagated along image boundaries which often correspond to motion boundaries. In addition, moving objects can be efficiently segmented in the least curvature direction. We show experimentally the benefits of the method and demonstrate robustness to fast rotational motion, such as what often occurs in human motion. © 2011 IEEE.

Liu F.,Zhejiang University | Wang L.,Jilin University | Sun Q.,Zhejiang University | Zhu L.,Jilin University | And 2 more authors.
Journal of the American Chemical Society | Year: 2012

Homogeneous catalysts usually show higher catalytic activities than heterogeneous catalysts because of their high dispersion of catalytically active sites. We demonstrate here that heterogeneous catalysts of ionic liquids functionalized on superhydrophobic mesoporous polymers exhibit much higher activities in transesterification to form biodiesel than homogeneous catalysts of the ionic liquids themselves. This phenomenon is strongly related to the unique features of high enrichment and good miscibility of the superhydrophobic mesoporous polymers for the reactants. These features should allow the design and development of a wide variety of catalysts for the conversion of organic compounds. © 2012 American Chemical Society.

Zhao Q.,National University of Singapore | Tan P.,National University of Singapore | Dai Q.,Jilin University | Shen L.,Institute for Infocomm Research | And 2 more authors.
IEEE Transactions on Pattern Analysis and Machine Intelligence | Year: 2012

We propose a method for intrinsic image decomposition based on retinex theory and texture analysis. While most previous methods approach this problem by analyzing local gradient properties, our technique additionally identifies distant pixels with the same reflectance through texture analysis, and uses these nonlocal reflectance constraints to significantly reduce ambiguity in decomposition. We formulate the decomposition problem as the minimization of a quadratic function which incorporates both the retinex constraint and our nonlocal texture constraint. This optimization can be solved in closed form with the standard conjugate gradient algorithm. Extensive experimentation with comparisons to previous techniques validate our method in terms of both decomposition accuracy and runtime efficiency. © 2012 IEEE.

Han C.,Heilongjiang University | Xie G.,Jilin University | Xu H.,Heilongjiang University | Zhang Z.,Jilin University | And 4 more authors.
Advanced Materials | Year: 2011

Highly efficient white organic light-emitting diodes (WOLEDs) with a simple, single-host-based structure are fabricated to realize the state-of-the-art performance of extremely low driving voltages, high efficiencies, and low efficiency roll-offs. This is the first single-host-based WOLED with both high efficiency and extremely low operating voltage at practical luminescence, demonstrating the great potential of these WOLEDs for portable display and lighting applications. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Home > Press > Quantum effects affect the best superconductor: Quantum effects explain why hydrogen sulphide is a superconductor at record-breaking temperatures Abstract: The theoretical results of a piece of international research published in Nature, whose first author is Ion Errea, a researcher at the UPV/EHU and DIPC, suggest that the quantum nature of hydrogen (in other words, the possibility of it behaving like a particle or a wave) considerably affects the structural properties of hydrogen-rich compounds (potential room-temperature superconducting substances). This is in fact the case of the superconductor hydrogen sulphide: a stinking compound that smells of rotten eggs, which when subjected to pressures a million times higher than atmospheric pressure, behaves like a superconductor at the highest temperature ever identified. This new advance in understanding the physics of high-temperature superconductivity could help to drive forward progress in the search for room-temperature superconductors, which could be used in levitating trains or next-generation supercomputers, for example. Superconductors are materials that carry electrical current with zero electrical resistance. Conventional or low-temperature ones behave that way only when the substance is cooled down to temperatures close to absolute zero (-273 °C o 0 degrees Kelvin). Last year, however, German researchers identified the high-temperature superconducting properties of hydrogen sulphide which makes it the superconductor at the highest temperature ever discovered: -70 °C or 203 K. The structure of the chemical bonds between atoms changes In classical or Newtonian physics it is possible to measure the position and momentum of a moving object to determine where it is going and how long it will take to reach its destination. These two properties are inherently linked. However, in the strange world of quantum physics, it is impossible, according to Heisenberg's uncertainty principle, for specific pairs of observable complementary physical magnitudes of a particle to be known at the same time. Hydrogen is the lightest element in the periodic table, so it is an atom that is very strongly affected by quantum behaviour. Its quantum nature affects the structural and physical properties of various hydrogen compounds. An example is high-pressure ice where quantum fluctuations of the proton lead to a change in the way the molecules are held together, due to the fact that the chemical bonds between atoms end up being symmetrical. The researchers in this study believe that a similar quantum hydrogen-bond symmetrisation occurs in the hydrogen sulphide superconductor. The researchers have formulated the calculations by considering the hydrogen atoms as quantum particles behaving like waves, and they have concluded that they form symmetrical bonds at a pressure similar to that used experimentally by the German researchers. So they have succeeded in explaining the phenomenon of superconductivity at record-breaking temperatures because in previous calculations hydrogen atoms were treated as classical particles, which made impossible to explain the experiment. All this highlights the fact that quantum physics and symmetrical hydrogen bonds lie behind high-temperature conductivity in hydrogen sulphide. The researchers are delighted that the good results obtained in this research show that quantitative predictions and computation can be used with complete confidence to speed up the discovery of high-temperature superconductors. According to the calculations made, the quantum symmetrisation of the hydrogen bonds has a great impact on the vibrational and superconducting properties of hydrogen sulphide. "In order to theoretically reproduce the observed pressure dependence of the superconducting critical temperature, the quantum symmetrisation needs to be taken into account," explained Ion Errea, the lead researcher in the study. This theoretical study shows that in hydrogen-rich compounds, the quantum motion of hydrogen can strongly affect the structural properties (even modifying the chemical bonding), as well as the electron-phonon interaction that drives the superconducting transition. In the view of the researchers, theory and computation have played a key role in the search for superconducting hydrides subjected to extreme compression. And they also pointed out that in the future an attempt will be made to increase the temperature until room-temperature superconductivity is achieved while dramatically reducing the pressures required. ### Additional information This international research was carried out with the collaboration of researchers from the UPV/EHU-University of the Basque Country and Donostia International Physics Center (DIPC), the UPMC Université Paris 06 (Sorbonne), the University of Cambridge (Cavendish Laboratory), the Jiangsu Normal University, the Carnegie Institution of Washington, Jilin University, and the University of Rome 'La Sapienza'. The lead researcher in the study was Ion Errea (Donostia-San Sebastian, 1984); he is a PhD holder in Physics and is currently a researcher at DIPC and a lecturer in the UPV/EHU's Department of Applied Physics. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Li G.,Jilin University | Zhu D.,Northeast Normal University | Peng T.,Jilin University | Liu Y.,Jilin University | And 2 more authors.
Advanced Functional Materials | Year: 2014

Two phosphorescent iridium complexes with bipolar transporting ability, namely FPPCA (500 nm) and BZQPG (600 nm), are synthesized and employed as an ideal host-guest system for phosphorescent organic light emitting diodes (PHOLEDs).The devices give very high-efficiency orange-red emission from BZQPG with maximum external quantum efficiency (EQE orext) of >27% and maximum power efficiency (PE or ηp) of >75 lm/W, and maintain high levels of 26% and 55 lm/W, 25% and 40 lm/W at high luminance of 1000 and 5000 cd m-2, respectively, within a range of 8-15 wt% of BZQPG. The realization of such high and stable EL performance results from the coexistence of two parallel paths: i) effective energy transfer from host (FPPCA) to guest (BZQPG) and ii) direct exciton formation on the BZQPG emitter, which can alternately dominate the electrophosphorescent emission. This all-phosphor doping system removes the charge-injection barrier from the charge-transport process to the emissive layer (EML) due to the inherent narrow E g of both phosphors. Therefore, this ideal host-guest system represents a new design to produce PHOLEDs with high efficiency and low efficiency roll-off using a simple device configuration. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Horsley S.A.R.,University of Exeter | Wu J.-H.,Jilin University | Artoni M.,Instituto Nazionale Of Ottica | Artoni M.,CNR Institute of Acoustics and Sensors Orso Mario Corbino | La Rocca G.C.,Normal School of Pisa
Physical Review Letters | Year: 2013

Reciprocity is fundamental to light transport and is a concept that holds also in rather complex systems. Yet, reciprocity can be switched off even in linear, isotropic, and passive media by setting the material structure into motion. In highly dispersive multilayers this leads to a fairly large forward-backward asymmetry in the pulse transmission. Moreover, in multilevel systems, this transport phenomenon can be all-optically enhanced. For atomic multilayer structures made of three-level cold Rb87 atoms, for instance, forward-backward transmission contrast around 95% can be obtained already at atomic speeds in the meter per second range. The scheme we illustrate may open up avenues for optical isolation that were not previously accessible. © 2013 American Physical Society.

Su J.,Shanghai JiaoTong University | Zou X.,Jilin University | Chen J.-S.,Shanghai JiaoTong University
RSC Advances | Year: 2014

The defect chemistry of metal oxides is a very important research aspect of inorganic solid-state materials. This is because (i) a certain amount of defects or imperfections are always present in metal oxide materials; (ii) the presence of defects affects, and even sometimes determines, the physical and chemical properties of the materials; and (iii) more importantly, defects do not necessarily have adverse effects on the properties of materials, and judicious "defect engineering" can bring about improved properties desired in material systems, and even some new useful functionalities that are not available to the "perfect" material. In this review, we specially highlight the recent research efforts toward understanding the defect chemistry of titanium dioxide (also known as titania, TiO2), a widely-studied multifunctional metal oxide. In the discussion, particular attention is paid to the synthesis of Ti3+/oxygen vacancy self-modified TiO2 materials and the favorable effects of these defects on the materials' properties and applications. This review, focusing on a representative metal oxide (i.e., TiO2), is anticipated to provide some new insights into the general defect chemistry of metal oxides, and to give impetus to the development of the "defect engineering" of metal oxide materials. © 2014 The Royal Society of Chemistry.

Li L.-L.,University of Illinois at Urbana - Champaign | Zhang R.,University of Illinois at Urbana - Champaign | Yin L.,University of Illinois at Urbana - Champaign | Zheng K.,Jilin University | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2012

Coat of lipids: Water-dispersible and functionalizable upconverting nanoparticles (UCNPs) for selective imaging of live cancer cells were synthesized. The synthetic approach involves coating the surface of the UCNPs with a monolayer of phospholipids that contain different functional groups (see picture), thus allowing for conjugation of many molecules for applications in fields such as bioinspired nanoassembly, biosensing, and biomedicine. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Guo X.,Jilin University | Song W.,Jilin University | Chen C.,University of Maine, United States | Di W.,Jilin University | Qin W.,Jilin University
Physical Chemistry Chemical Physics | Year: 2013

A novel near-infrared (NIR)-responsive photocatalyst, β-NaYF 4:Yb3+,Tm3+@ZnO composites, was prepared by a two-step high temperature thermolysis method. In the NIR-responsive photocatalysis, β-NaYF4:Yb,Tm served as a NIR-to-UV upconverter and provided "UV light" or "necessary energy" to the ZnO catalyst. The energy transfer in the composites and the mixtures of β-NaYF4:Yb,Tm and ZnO was studied by using steady-state and dynamic fluorescence spectroscopy. The NIR photocatalytic activities were investigated by the decomposition of Rhodamine B. It was found that the energy transfer processes dominated the overall photocatalytic activities, and the generation of hydroxyl radicals was the origin of organic pollutant decomposition under NIR irradiation. This journal is © the Owner Societies 2013.

Qi D.,Chang'an University | Leick M.,University of Illinois at Urbana - Champaign | Liu Y.,Jilin University | Lee C.-F.F.,University of Illinois at Urbana - Champaign
Fuel | Year: 2011

In this study, the effect of injection timing and EGR rate on the combustion and emissions of a Ford Lion V6 split injection strategy direct injection diesel engine has been experimentally investigated by using neat biodiesel produced from soybean oil. The results showed that, with the increasing of EGR rate, the brake specific fuel combustion (BSFC) and soot emission were slightly increased, and nitrogen oxide (NOx) emission was evidently decreased. Under higher EGR rate, the peak pressure was slightly lower, and the peak heat release rate kept almost identical at lower engine load, and was higher at higher engine load. With the main injection timing retarded, BSFC was slightly increased, NOx emission was evidently decreased, and soot emission hardly varied. The second peak pressure was evidently decreased and the heat release rate was slightly increased. © 2010 Elsevier Ltd. All rights reserved.

Zhu S.,Jilin University | Ma Z.,Shanghai JiaoTong University
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2010

In this Letter, we study various physically important topologies on the set S (H) of states of standard quantum mechanics, and find the relationship between them. Our result extends the results in S. Bugajski (1994) [11]. © 2010 Elsevier B.V. All rights reserved.

Yu T.,Jilin University | Yu T.,Heilongjiang University
Systems and Control Letters | Year: 2011

This paper deals with the transmission problem in simultaneous stabilization of time-varying linear systems. We establish two criteria for the transitivity in simultaneous stabilization. In particular, we give a necessary and sufficient condition for certain linear systems to satisfy a strengthened version of transitivity. © 2010 Elsevier B.V. All rights reserved.

Sun L.,Heilongjiang University | Tian C.,Heilongjiang University | Fu Y.,Jilin University | Yang Y.,Heilongjiang University | And 3 more authors.
Chemistry - A European Journal | Year: 2014

An advanced supercapacitor material based on nitrogen- doped porous graphitic carbon (NPGC) with high a surface area was synthesized by means of a simple coordination- pyrolysis combination process, in which tetraethyl orthosilicate (TEOS), nickel nitrate, and glucose were adopted as porogent, graphitic catalyst precursor, and carbon source, respectively. In addition, melamine was selected as a nitrogen source owing to its nitrogen-enriched structure and the strong interaction between the amine groups and the glucose unit. A low-temperature treatment resulted in the formation of a NPGC precursor by combination of the catalytic precursor, hydrolyzed TEOS, and the melamine-glucose unit. Following pyrolysis and removal of the catalyst and porogent, the NPGC material showed excellent electrical conductivity owing to its high crystallinity, a large Brunauer- Emmett-Teller surface area (SBET=1027 m2g-1), and a high nitrogen level (7.72 wt%). The unusual microstructure of NPGC materials could provide electrochemical energy storage. The NPGC material, without the need for any conductive additives, showed excellent capacitive behavior (293 Fg-1 at 1 Ag-1), long-term cycling stability, and high coulombic efficiency (>99.9% over 5000 cycles) in KOH when used as an electrode. Notably, in a two-electrode symmetric supercapacitor, NPGC energy densities as high as 8.1 and 47.5 Whkg-1, at a high power density (10.5 kWkg-1), were achieved in 6m KOH and 1m Et4NBF4-PC electrolytes, respectively. Thus, the synthesized NPGC material could be a highly promising electrode material for advanced supercapacitors and other conversion devices. © 2014 Wiley-VCH Verlag GmbH& Co. KGaA, Weinheim.

Liu L.,University of Connecticut | Liu S.,Jilin University
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing | Year: 2014

The stepped-frequency continuous wave (SFCW) radar technique was used to detect cardio-respiratory signals as the vital sign from a human subject positioned behind obstacles under laboratory conditions. The experiments were organized with a number of detection scenarios by collecting data from a group of human subjects. The experiments also investigated the effect of varying thickness of the obstacles, human subject postures, status of breathing, position of radar antenna relative to human subject's chest, as well as the length of survey times. The experimental results have shown that respiration as the primary vital sign can be detected with very high confidence and should be highlighted in developing radar systems for search and rescue for earthquake disaster survivors. Among the four human subject postures of face up, face down, face left, and face right, detection of the cardiologic signals can solely be achieved possibly when the subject was facing up. When the radar antennas to be placed at certain offset, not directly above the human subject's chest, it is still possible for good detection of the breathing signal. The minimum recording time for extracting respiration signal can be as short as 5 s. Even be conservative, a period of 30 s should be long enough for catching the respiratory signal with high signal to noise ratio. © 2008-2012 IEEE.

Song W.,Jilin University | Mano J.F.,University of Minho | Mano J.F.,European Institute of Excellence on Tissue Engineering and Regenerative Medicine
Soft Matter | Year: 2013

Regulation of protein adsorption and cell adhesion on surfaces is a key aspect in the field of biomedicine and tissue engineering. Beside the general studies on hydrophilic/hydrophobic surfaces, there are both fundamental and practical interests to extend the investigation of the interaction between proteins or cells and surfaces to the two extreme wettability ranges, namely superhydrophilicity and superhydrophobicity. This review gave an overview of recent studies on proteins or cells action on these two special wettability ranges. The first part will focus on the interaction between proteins and superhydrophilic/superhydrophobic surfaces. The second part will focus on cells adhesion on these extreme wettable surfaces. Surfaces can be patterned to control in space the wettability within extreme values. As an application of such substrates, flat chips for high-throughput screening are also addressed to offer new insight on the design of a new type of bioanalysis supports. © 2013 The Royal Society of Chemistry.

Liu Y.,Shanghai JiaoTong University | Yu C.,Shanghai JiaoTong University | Jin H.,Shanghai JiaoTong University | Jiang B.,Shanghai JiaoTong University | And 4 more authors.
Journal of the American Chemical Society | Year: 2013

Herein, we report a novel Janus particle and supramolecular block copolymer consisting of two chemically distinct hyperbranched polymers, which is coined as Janus hyperbranched polymer. It is constructed by the noncovalent coupling between a hydrophobic hyperbranched poly(3-ethyl-3-oxetanemethanol) with an apex of an azobenzene (AZO) group and a hydrophilic hyperbranched polyglycerol with an apex of a β-cyclodextrin (CD) group through the specific AZO/CD host-guest interactions. Such an amphiphilic supramolecular polymer resembles a tree together with its root very well in the architecture and can further self-assemble into unilamellar bilayer vesicles with narrow size distribution, which disassembles reversibly under the irradiation of UV light due to the trans-to-cis isomerization of the AZO groups. In addition, the obtained vesicles could further aggregate into colloidal crystal-like close-packed arrays under freeze-drying conditions. The dynamics and mechanism for the self-assembly of vesicles as well as the bilayer structure have been disclosed by a dissipative particle dynamics simulation. © 2013 American Chemical Society.

Bo Y.,Jilin University | Liu J.,Hong Kong Baptist University | Feng J.,University of Warwick
IEEE Transactions on Knowledge and Data Engineering | Year: 2012

Network communities refer to groups of vertices within which their connecting links are dense but between which they are sparse. A network community mining problem (or NCMP for short) is concerned with the problem of finding all such communities from a given network. A wide variety of applications can be formulated as NCMPs, ranging from social and/or biological network analysis to web mining and searching. So far, many algorithms addressing NCMPs have been developed and most of them fall into the categories of either optimization based or heuristic methods. Distinct from the existing studies, the work presented in this paper explores the notion of network communities and their properties based on the dynamics of a stochastic model naturally introduced. In the paper, a relationship between the hierarchical community structure of a network and the local mixing properties of such a stochastic model has been established with the large-deviation theory. Topological information regarding to the community structures hidden in networks can be inferred from their spectral signatures. Based on the above-mentioned relationship, this work proposes a general framework for characterizing, analyzing, and mining network communities. Utilizing the two basic properties of metastability, i.e., being locally uniform and temporarily fixed, an efficient implementation of the framework, called the LM algorithm, has been developed that can scalably mine communities hidden in large-scale networks. The effectiveness and efficiency of the LM algorithm have been theoretically analyzed as well as experimentally validated.

Wu Y.-L.,Guangdong General Hospital and Guangdong Academy of Medical science | Zhou C.,Shanghai Pulmonary Hospital | Hu C.-P.,Central South University | Feng J.,Jiangsu Provincial Tumor Hospital | And 11 more authors.
The Lancet Oncology | Year: 2014

Background: Afatinib-an oral irreversible ErbB family blocker-improves progression-free survival compared with pemetrexed and cisplatin for first-line treatment of patients with EGFR mutation-positive advanced non-small-cell lung cancer (NSCLC). We compared afatinib with gemcitabine and cisplatin-a chemotherapy regimen widely used in Asia-for first-line treatment of Asian patients with EGFR mutation-positive advanced NSCLC. Methods: This open-label, randomised phase 3 trial was done at 36 centres in China, Thailand, and South Korea. After central testing for EGFR mutations, treatment-naive patients (stage IIIB or IV cancer [American Joint Committee on Cancer version 6], performance status 0-1) were randomly assigned (2:1) to receive either oral afatinib (40 mg per day) or intravenous gemcitabine 1000 mg/m2 on day 1 and day 8 plus cisplatin 75 mg/m2 on day 1 of a 3-week schedule for up to six cycles. Randomisation was done centrally with a random number-generating system and an interactive internet and voice-response system. Randomisation was stratified by EGFR mutation (Leu858Arg, exon 19 deletions, or other; block size three). Clinicians and patients were not masked to treatment assignment, but the independent central imaging review group were. Treatment continued until disease progression, intolerable toxic effects, or withdrawal of consent. The primary endpoint was progression-free survival assessed by independent central review (intention-to-treat population). This study is registered with, NCT01121393. Findings: 910 patients were screened and 364 were randomly assigned (242 to afatinib, 122 to gemcitabine and cisplatin). Median progression-free survival was significantly longer in the afatinib group (11·0 months, 95% CI 9·7-13·7) than in the gemcitabine and cisplatin group (5·6 months, 5·1-6·7; hazard ratio 0·28, 95% CI 0·20-0·39; p<0·0001). The most common treatment-related grade 3 or 4 adverse events in the afatinib group were rash or acne (35 [14·6%] of 239 patients), diarrhoea (13 [5·4%]), and stomatitis or mucositis (13 [5·4%]), compared with neutropenia (30 [26·5%] of 113 patients), vomiting (22 [19·5%]), and leucopenia (17 [15·0%]) in the gemcitabine and cisplatin group. Treatment-related serious adverse events occurred in 15 (6·3%) patients in the afatinib group and nine (8·0%) patients in the gemcitabine and cisplatin group. Interpretation: First-line afatinib significantly improves progression-free survival with a tolerable and manageable safety profile in Asian patients with EGFR mutation-positive advanced lung NSCLC. Afatinib should be considered as a first-line treatment option for this patient population. Funding: Boehringer Ingelheim. © 2014 Elsevier Ltd.

Yuan B.,CAS Changchun Institute of Applied Chemistry | Zheng C.,Heilongjiang University | Teng H.,Jilin University | You T.,CAS Changchun Institute of Applied Chemistry
Journal of Chromatography A | Year: 2010

A rapid and simple method was demonstrated for the analysis of atropine, anisodamine, and scopolamine by nonaqueous capillary electrophoresis (NACE) coupled with electrochemiluminescence (ECL) and electrochemistry (EC) dual detection. The mixture of acetonitrile (ACN) and 2-propanol containing 1 M acetic acid (HAc), 20 mM sodium acetate (NaAc), and 2.5 mM tetrabutylammonium perchlorate (TBAP) was used as the electrophoretic buffer. Although a short capillary of 18 cm was used, the decoupler was not needed and the separation efficiency was good. The linear ranges of atropine, anisodamine, and scopolamine were 0.5-50, 5-2000, and 50-2000 μM, respectively. For six replicate measurements of 100 μM scopolamine, 15 μM atropine, and 200 μM anisodamine, the RSDs of ECL intensity, EC current, and migration time were less than 3.6%, 4.5%, and 0.3%, respectively. In addition, because the organic buffer was used, the working electrode (Pt) was not easily fouled and did not need reactivation. The method was also applied for the determination of these three alkaloids in Flos daturae extract. © 2009 Elsevier B.V. All rights reserved.

News Article | October 30, 2015

Whispering-Gallery-Mode (WGM) microcavities that confine light in a small volume with high quality (Q) factors and enhance interaction of light with matters inside the cavity have shown promising applications as an element for a variety of devices such as micro-lasers, micro-sensors, micro-filters, and thus are becoming the basic building blocks of integrated photonic systems. This leads to tremendous progress in the development of micro-scale high-Q microcavity processing technologies. In a review entitled "Femtosecond laser 3D fabrication of whispering-gallery-mode microcavities" by Huailiang Xu and Hongbo Sun at the State Key Laboratory on Integrated Optoelectronics, Jilin University, recent progress in femtosecond laser three-dimensional fabrications of optical WGM microcavities was overviewed. This review was published in Science China Physics, Mechanics & Astronomy (volume 58, Issue 11). Femtosecond laser direct writing has attracted a lot of attention in recent years, and demonstrated the versatility in fabrication of a variety of devices from micro-fluidics, optoelectronics, micro-electronics, micro-machines, micro-sensing, to micro-biomimetics and micro-optics, etc. However, the reports on the fabrication of high-Q WGM microcavities appeared only recently. This review article began with a brief introduction of the basic principle of femtosecond laser processing, in which the 3D capability of high-quality micro-fabrication of femtosecond laser processing technique is discussed. Subsequently, the fabrications of 3D passive and active WGMs microcavities in a variety of materials including polymer, glass and crystals were demonstrated. The fabrication of the integrated device of a micro-sensor incorporated with WGM microcavity was also introduced. They pointed out that fabricating microcavities with extremely high Q factors in the range of 108-1010 by using femtosecond laser direct writing is still challenging. However, "it is believed," the two researchers said, "the further effort on the investigation of femtosecond laser 3D fabrication of high-Q factor microcavities will undoubtedly benefit the applications of microcavities in a broad spectrum from bio-sensing and optoelectronics to quantum information.." Explore further: Plasmonic whispering gallery microcavity paves the way to future nanolasers More information: HuaiLiang Xu et al. Femtosecond laser 3D fabrication of whispering-gallery-mode microcavities, Science China Physics, Mechanics & Astronomy (2015). DOI: 10.1007/s11433-015-5720-5

Wang Y.,CAS Nanjing Institute of Geology and Palaeontology | Huang C.,Sichuan University | Sun B.,Lanzhou University | Quan C.,Jilin University | And 3 more authors.
Earth-Science Reviews | Year: 2014

The Cretaceous was one of the most remarkable periods in geological history, with a "greenhouse" climate and several important geological events. Reconstructions of atmospheric CO2 using proxies are crucial for understanding the Cretaceous "greenhouse." In this paper we summarize the major approaches for reconstructing CO2 based on paleobotanical or geochemical data, and synthesize the CO2 variations throughout the Cretaceous. The results show that atmospheric CO2 levels remained relatively high throughout the Cretaceous, but were lower in the early Cretaceous, highest in the mid-Cretaceous and gradually declined during the late Cretaceous. However, this overall trend was interrupted by several rapid changes associated with ocean anoxic events (OAEs) and the end-Cretaceous catastrophic event. New data on paleo-CO2 levels from paleobotanical and paleosol evidences support not only the overall trends indicated by geochemical models, but provide more precise records of the short-term fluctuations related to brief episodes of climate change. Temporal resolution within the long quiet magnetic period in the middle Cretaceous is one of the obstacles preventing us from a more comprehensive understanding of the CO2 climate linkage. But new paleo-CO2 determinations and climatic data from stratigraphic sections of sediments intercalated with datable volcanic rocks will allow a better understanding of the relationships between fluctuations of atmospheric CO2, climate change, and geological events. © 2013 Elsevier B.V.

Zhou T.,Jilin University | Jia T.,Jilin University | Kang B.,Jilin University | Li F.,Jilin University | And 2 more authors.
Advanced Energy Materials | Year: 2011

The development of non-fullerene-based electron acceptors (especially organic molecules with sufficient absorption property within the solar spectrum region) for bulk-heterojunction (BHJ) organic solar cells (OSCs) is an important issue for the achievement of high photoconversion efficiency. In this contribution, a new class of organic acceptors di-cyan substituted quinacridone derivatives (DCN-n CQA, n = 4, 6 and 8) for BHJ solar cells was designed and synthesized. DCN-n CQA molecules possess facile synthesis, solution processability, visible and near-IR light absorption and relatively stable characteristics. The DCN-8CQA molecule exhibited a proper LUMO energy level (-4.1 eV), small bandgap (1.8 eV) and moderate electron mobility (10 -4 cm 2 V -1 S -1), suggesting that this molecule is an ideal acceptor material for the classical donor material regio-regular poly (3-hexylthiophene) (P3HT). A photovoltaic device with a structure of [ITO/PEDOT:PSS/P3HT:DCN-8CQA/LiF/Al] displayed a power conversion efficiency of 1.57% and a fill factor of 57% under 100 mW cm -2 AM 1.5G simulated solar illumination. The DCN-n CQA molecules showed remarkable absorption in the region from 650 to 700 nm, where P3HT has a weak absorption promoting overlap with the solar spectrum and potentially improving the performance of the solar cell. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wang X.,Jilin University | Deng X.,Beihang University | Zhang X.,Jilin University
PLoS ONE | Year: 2014

Amelogenin, the major enamel matrix protein in tooth development, has been demonstrated to play a significant role in tooth enamel formation. Previous studies have identified the alternative splicing of amelogenin in many mammalian vertebrates as one mechanism for amelogenin heterogeneous expression in teeth. While amelogenin and its splicing forms in mammalian vertebrates have been cloned and sequenced, the amelogenin gene, especially its splicing forms in nonmammalian species, remains largely unknown. To better understand the mechanism underlying amelogenin evolution, we previously cloned and characterized an amelogenin gene sequence from a squamate, the green iguana. In this study, we employed RT-PCR to amplify the amelogenin gene from the black spiny-tailed iguana Ctenosaura similis teeth, and discovered a novel splicing form of the amelogenin gene. The transcript of the newly identified iguana amelogenin gene (named C. Similis-T2L) is 873 nucleotides long encoding an expected polypeptide of 206 amino acids. The C. Similis-T2L contains a unique exon denominated exon X, which is located between exon 5 and exon 6. The C. Similis-T2L contains 7 exons including exon 1, 2, 3, 5, X, 6, and 7. Analysis of the secondary and tertiary structures of T2L amelogenin protein demonstrated that exon X has a dramatic effect on the amelogenin structures. This is the first report to provide definitive evidence for the amelogenin alternative splicing in non-mammalian vertebrates, revealing a unique exon X and the splicing form of the amelogenin gene transcript in Ctenosaura similis. © 2012 Wang et al.

Li D.,Jilin University | Li D.,Hong Kong University of Science and Technology | Liu J.,Hong Kong University of Science and Technology | Kwok R.T.K.,Hong Kong University of Science and Technology | And 3 more authors.
Chemical Communications | Year: 2012

Mesoporous SBA-15 functionalized with aggregation-induced emission (AIE) luminogens serves as an efficient and recyclable fluorescent sensor for the detection of picric acid (PA), with a quenching constant of up to 2.5 × 10 5 M -1 in a water solution, presenting a new model for the supersensitive detection of explosives. © 2012 The Royal Society of Chemistry.

Qi Z.,Jilin University | Qi Z.,Jilin Institute of Architecture and Civil Engineering | Gao Q.,Jilin University | Liu Y.,Jilin University | And 2 more authors.
Renewable and Sustainable Energy Reviews | Year: 2014

Hybrid energy systems (HES) facilitate the efficient utilization of renewable resources and sustainable energy, and they are expected to be more prevalent in the future. With ground source heat pump (GSHP) as the main body and core technology, the hybrid ground source heat pump (HGSHP) system is used frequently in recent years and its integration and synthesis skills face higher requirements. The worldwide hybrid system has usually been composed of types of energy source devices, such as solar collector, boiler (coal, gas, oil), electric heater, waste energy device, cooling tower, cooler, and thermal storage system with natural cold and hot. Actually, they lead to the complicated unsteady processes and various hybrid energy systems. In China, the applications of these systems are growing year by year, but the new technology breakthrough is being in difficulty and even in an awkward situation. This paper review the progress of GSHP combined with HES all over the world, and surveyed the development of HGSHP in China. Meanwhile, the basic proposals for development in the future are presented to make up the gap in the field of HES and HGSHP. A coming work aims to research the basic problems during the demonstration application, such as investigation of system design parameters, component configuration and control strategies of a HGSHP system. These problems will strengthen theoretical and practical understanding of HES and facilitate more extensive application of HGSHP in China. © 2013 Elsevier Ltd.

Li Z.,Harbin Institute of Technology | Liu J.,Harbin Normal University | Li J.,Jilin University | Shen J.,Harbin Institute of Technology
Nanoscale | Year: 2012

Crystallized and fluorinated nanoporous Ta 2O 5 spheres were prepared by a combination of co-precipitation and hydrothermal methods in a NH 4F-containing water solution. The as-prepared porous spheres, with a pore-size of around 7 nm and a large specific surface area of 132 m 2 g -1, show superior photocatalytic hydrogen production activity over P25 and commercial-Ta 2O 5. © 2012 The Royal Society of Chemistry.

Shao Y.-H.,Zhejiang University of Technology | Wang Z.,Jilin University | Chen W.-J.,Zhejiang University of Technology | Deng N.-Y.,China Agricultural University
Knowledge-Based Systems | Year: 2013

For the recently proposed projection twin support vector machine (PTSVM) [1], we propose a simpler and reasonable variant from theoretical point of view, called projection twin support vector machine with regularization term, RPTSVM for short. Note that only the empirical risk minimization is introduced in primal problems of PTSVM, incurring the possible singularity problems. Our RPTSVM reformulates the primal problems by adding a maximum margin regularization term, and, therefore, the singularity is avoided and the regularized risk principle is implemented. In addition, the nonlinear classification ignored in PTSVM is also considered in our RPTSVM. Further, a successive overrelaxation technique and a genetic algorithm are introduced to solve our optimization problems and to do the parameter selection, respectively. Computational comparisons of our RPTSVM against original PTSVM, TWSVM and MVSVM indicate that our RPTSVM obtains better generalization than others. © 2012 Elsevier B.V. All rights reserved.

Wang G.,Hong Kong University of Science and Technology | Wang G.,Jilin University | Zhang T.-Y.,Hong Kong University of Science and Technology
Journal of Colloid and Interface Science | Year: 2012

Hierarchical nanostructured CuO surface was embellished to amplify the wettability. The pristine superhydrophilic CuO surface spontaneously transited to be superhydrophobic after exposed in air at room temperature for about 3. weeks. The wettability change is attributed to the adsorption of oxygen molecules on the topmost layer according to the surface chemical analysis. The adsorbed oxygen molecules could be removed by dipping the sample into l-Ascorbic acid solution for 10. s, leading to the recovery of the pristine superhydrophilicity. © 2012 Elsevier Inc..

Di J.,Jilin University | Zhao Y.,Beihang University | Yu J.,Jilin University
Journal of Materials Chemistry | Year: 2011

Molecular sieves, such as zeolites and mesoporous materials, have been widely used in the fields of catalysis, adsorption, ion-exchange, and are finding new applications in optics, electronics, magnetism, medicine, etc. Molecular sieves with different morphologies or aggregation states, such as spheres, films, and fibers have been prepared to fulfil the need for various applications. Electrospinning offers a simple and straightforward way for generating ultrafine fibers with diameter in the range of nanometres to micrometres from a variety of materials. In recent decades, electrospinning has been introduced to prepare molecular sieve fibers. In this review, fibrous molecular sieves including zeolite fibers, siliceous and nonsiliceous mesoporous fibers prepared by electrospinning are summarized, and their prominent applications in optics, adsorptions, catalysis, etc. are highlighted. © 2011 The Royal Society of Chemistry.

Deng H.,Beihang University | Hao W.,Beihang University | Xu H.,Beihang University | Wang C.,Jilin University
Journal of Physical Chemistry C | Year: 2012

Oxygen vacancy is an intrinsic defect in metal oxides, which has a great effect on the electronic structures and physical properties. The influence of the intrinsic oxygen vacancy on the crystal and electronic structures of β-Bi 2O 3 has been studied. Results show that the vacancy is preferred to occupy the tetrahedral O3 (8c) site. It makes β-Bi 2O 3 lose I23 symmetry and leads to flat band structure. The quadrivalence post-transition ions M 4+ (M = S, Se, or Te) doping can keep I23 symmetry by forming MO 4 units, and can result in dispersive valence bands and energy levels in the band gaps. These characters are beneficial for the mobility of the photogenerated carriers. © 2011 American Chemical Society.

Zhao J.-X.,Jilin University | Ding Y.-H.,Harbin Normal University
Diamond and Related Materials | Year: 2010

The unsatisfactory stability of CNT under high temperature or subject to strong oxidants has limited the potential use of p- and n-type field-effect transistors (FETs). Promisingly, boron nitride (BN) nanotubes are known to have the excellent resistance to oxidant and thermal stability at high temperature as well as the uniform electronic properties, which rends their possible application as alternative FET device. In this paper, through the theoretical computation of the noncovalent functionalization of BN nanotube by various aromatic molecules (including C10H8, C14H 10, porphyrin, DDQ, and TCNQ molecules), we for the first time evaluate its possibility as a candidate of stable FET device. We find that: (i) these aromatic molecules can be stably adsorbed on the studied BN with the adsorption energy ranging from - 0.22 (C10H8) to - 0.42 eV (porphyrin); (ii) the adsorption of electrophilic molecules on the outer sidewall of BN nanotube realizes a p-type semiconductor with a smaller band gap (~ 0.90 eV); (iii) exoherdral adsorption of nucleophilic aromatic molecules leads to an n-type semiconductor. This novel BN nanotube-based material offers great promise for molecule electronics in terms of their good stability. © 2010 Elsevier B.V. All rights reserved.

Meng L.,Jilin University | Zheng Y.,Jilin University | Hui R.,Peking Union Medical College
Hypertension Research | Year: 2013

To assess whether habitual sleep duration or insomnia increase the incidence of hypertension. PubMed, EMBASE and Cochrane were searched without language restriction. Prospective cohort studies of adults with at least a 1-year follow-up duration were included. Habitual sleep duration or symptoms of insomnia were assessed as baseline exposure, and the outcome was incidence of hypertension. Subgroup, meta-regression and sensitivity analyses were conducted to assess heterogeneity, and Egger's test was used to assess publication bias. Eleven studies (17 cohorts) were included. Short sleep duration, sleep continuity disturbance (SCD), early-morning awakening (EMA) and combined symptoms of insomnia increased the risk of hypertension incidence (the relative risks (95% confidence intervals) were 1.21 (1.05-1.40) for short sleep duration, 1.20 (1.06-1.36) for SCD, 1.14 (1.07-1.20) for EMA and 1.05 (1.01-1.08) for combined insomnia symptoms). Less evidence exists to support conclusions about the association between long sleep duration or difficulty falling asleep (DFA) and hypertension incidence. No obvious heterogeneity or publication biases were found. Our meta-analysis demonstrates that short sleep duration and single/combined symptoms of insomnia (except DFA) are associated with an increased risk of hypertension incidence. It is important to consider sleep duration and insomnia during hypertension prevention and treatment. More laboratory studies on potential mechanisms and prospective observational studies with objective measures of sleep are needed. © 2013 The Japanese Society of Hypertension. All rights reserved.

Zou X.,Jilin University | Zhang Y.,Beihang University
Chemical Society Reviews | Year: 2015

Sustainable hydrogen production is an essential prerequisite of a future hydrogen economy. Water electrolysis driven by renewable resource-derived electricity and direct solar-to-hydrogen conversion based on photochemical and photoelectrochemical water splitting are promising pathways for sustainable hydrogen production. All these techniques require, among many things, highly active noble metal-free hydrogen evolution catalysts to make the water splitting process more energy-efficient and economical. In this review, we highlight the recent research efforts toward the synthesis of noble metal-free electrocatalysts, especially at the nanoscale, and their catalytic properties for the hydrogen evolution reaction (HER). We review several important kinds of heterogeneous non-precious metal electrocatalysts, including metal sulfides, metal selenides, metal carbides, metal nitrides, metal phosphides, and heteroatom-doped nanocarbons. In the discussion, emphasis is given to the synthetic methods of these HER electrocatalysts, the strategies of performance improvement, and the structure/composition-catalytic activity relationship. We also summarize some important examples showing that non-Pt HER electrocatalysts could serve as efficient cocatalysts for promoting direct solar-to-hydrogen conversion in both photochemical and photoelectrochemical water splitting systems, when combined with suitable semiconductor photocatalysts. This journal is © The Royal Society of Chemistry.

Yang Y.,Jilin University | Lu N.,Jilin University | Chen D.,Jilin University | Meng L.,Jilin University | And 2 more authors.
American Journal of Clinical Nutrition | Year: 2012

Background: Previous studies indicate that oral supplementation with n-3 PUFA protects against atherosclerotic disease by inhibiting inflammatory processes, which underlie atherosclerosis and are reflected by the plasma concentrations of soluble adhesion molecules. However, consistent results were not obtained among studies. Objective: The objective was to assess the effects of n-3 PUFA supplementation on plasma concentrations of soluble adhesion molecules. Design: We conducted a meta-analysis of randomized controlled trials identified from PubMed, Embase, the Cochrane Library, and reference lists of relevant articles and reviews. Results: Eighteen studies were included. n-3 PUFA supplementation reduced plasma concentrations of soluble intercellular adhesion molecule- 1 [sICAM-1; weighted mean difference (WMD): -5.17; 95% CI: -10.07, -0.27; P = 0.04] but had no significant effects on soluble vascular cell adhesion molecule-1 (WMD: -5.90; 95% CI: -17.63, 5.84; P = 0.32), soluble P-selectin (WMD: -1.53; 95% CI: -4.33, 1.28; P = 0.29), or soluble E-selectin (WMD: 0.46; 95% CI: -1.54, 2.46; P = 0.65). Subgroup analysis stratified by the subjects' health status showed that n-3 PUFA supplementation reduced sICAM-1 concentrations in healthy subjects (WMD: -8.87; 95% CI: -15.20, -2.53; P = 0.006; heterogeneity test: I2 = 0%, P = 0.76) and in subjects with dyslipidemia (WMD: -15.31; 95% CI: -26.82, -3.81; P = 0.009; heterogeneity test: I2 = 26%, P = 0.26). Conclusions: n-3 PUFA supplementation can reduce plasma concentrations of sICAM-1. The effect is identified in both healthy subjects and subjects with dyslipidemia, which supports the hypothesis that n-3 PUFA can be supplemented as a primary or secondary means for preventing the development as well as the progression of atherosclerosis. © 2012 American Society for Nutrition.

Shao Y.-H.,Zhejiang University of Technology | Wang Z.,Jilin University | Chen W.-J.,Zhejiang University of Technology | Deng N.-Y.,China Agricultural University
Applied Intelligence | Year: 2013

In this paper, we propose a novel least squares twin parametric-margin support vector machine (TPMSVM) for binary classification, called LSTPMSVM for short. LSTPMSVM attempts to solve two modified primal problems of TPMSVM, instead of two dual problems usually solved. The solution of the two modified primal problems reduces to solving just two systems of linear equations as opposed to solving two quadratic programming problems along with two systems of linear equations in TPMSVM, which leads to extremely simple and fast algorithm. Classification using nonlinear kernel with reduced technique also leads to systems of linear equations. Therefore our LSTPMSVM is able to solve large datasets accurately without any external optimizers. Further, a particle swarm optimization (PSO) algorithm is introduced to do the parameter selection. Our experiments on synthetic as well as on several benchmark data sets indicate that our LSTPMSVM has comparable classification accuracy to that of TPMSVM but with remarkably less computational time. © 2013 Springer Science+Business Media New York.

Chen H.,Peking Union Medical College | Liu Y.,Peking Union Medical College | Jiang X.,Jilin University | Chen M.,Peking Union Medical College | Wang H.,Peking Union Medical College
Antimicrobial Agents and Chemotherapy | Year: 2010

The incidence of methicillin-resistant Staphylococcus aureus (MRSA) has been increasing yearly at Peking Union Medical College Hospital (PUMCH). In order to understand the molecular evolution of MRSA at PUMCH, a total of 466 nonduplicate S. aureus isolates, including 302 MRSA and 164 methicillin- susceptible (MSSA) isolates recovered from 1994 to 2008 were characterized by staphylococcal cassette chromosome mec (SCCmec) typing, spa typing, pulsed-field gel electrophoresis (PFGE), and multilocus sequence typing (MLST). The 302 MRSA isolates were classified into 12 spa types and 9 sequence types (STs). During the years from 1994 to 2000, the most predominant MRSA clone was ST239-MRSA-III-spa t037. Since 2000, ST239-MRSA-III-spa t030 has rapidly replaced t037 and become the major clone. Another clone, ST5-MRSA-II-spa t002 emerged in 2002 and constantly existed at a low prevalence rate. The 164 MSSA isolates were classified into 62 spa types and 40 STs. ST398 was the most common MLST type for MSSA, followed by ST59, ST7, ST15, and ST1. Several MSSA genotypes, including ST398, ST1, ST121, and ST59, were identical to well-known epidemic communityacquired MRSA (CA-MRSA) isolates. MLST eBURST analysis revealed that the ST5, ST59, and ST965 clones coexisted in both MRSA and MSSA, which suggested that these MRSA clones might have evolved from MSSA by the acquisition of SCCmec. Two pvl-positive ST59-MRSA-IV isolates were identified as CA-MRSA according to the clinical data. Overall, our data showed that the ST239-MRSA-III-spa t037 clone was replaced by the emerging ST239-MRSA-III-spa t030 clone, indicating a rapid change of MRSA at a tertiary care hospital in China over a 15-year period. Copyright © 2010, American Society for Microbiology. All Rights Reserved.

Shao Y.-H.,Zhejiang University of Technology | Deng N.-Y.,China Agricultural University | Yang Z.-M.,Zhejiang University of Technology | Chen W.-J.,Zhejiang University of Technology | Wang Z.,Jilin University
Knowledge-Based Systems | Year: 2012

In many cases, the output of a classifier should be a calibrated posterior probability to enable post-processing. However, twin support vector machines (TWSVM) do not provide such probabilities. In this paper, we propose a TWSVM probability model, called PTWSVM, to estimate the posterior probability. Note that our model is quite different from the SVM probability model because of the different mechanism of TWSVM and SVM. In fact, for TWSVM, we first define a new ranking continues output by comparing the distances between the sample and the two non-parallel hyperplanes, and then map this ranking continues output into probability by training the parameters of an additional sigmoid function. Our PTWSVM has been tested on both artificial datasets and several data-mining-style datasets, and the numerical experiments indicate that PTWSVM yields nice results. © 2012 Elsevier B.V. All rights reserved.

Wen Q.,Jilin University | Di J.,Jilin University | Jiang L.,Beihang University | Yu J.,Jilin University | Xu R.,Jilin University
Chemical Science | Year: 2013

Oil-water separations are helping with urgent issues due to increasing industrial oily wastewater, as well as frequent oil spill accidents. Membrane-based materials with special wettability are desired to separate oils from water. However, fabrication of energy-efficient and stable membranes that are suitable for practical oil-water separation remains challenging. Zeolite films have attracted intense research interest due to their unique pore character, excellent chemical, thermal and mechanical stability, etc. Here we first demonstrate zeolite-coated mesh films for gravity-driven oil-water separation. High separation efficiency of various oils can be achieved based on the excellent superhydrophilicity and underwater superoleophobicity of the zeolite surface. Flux and intrusion pressure are tunable by simply changing the pore size, dependent on the crystallization time of the zeolite crystals, of the zeolite meshes. More importantly, such films are corrosion-resistant in the presence of corrosive media, which gives them promise as candidates in practical applications of oil-water separation. © The Royal Society of Chemistry 2013.

Wen Q.,Jilin University | Di J.,Jilin University | Zhao Y.,Beihang University | Wang Y.,Jilin University | And 2 more authors.
Chemical Science | Year: 2013

Organic molecule pollution in industrial and agricultural sewage is a serious threat to the environment and human health. Adsorption membranes have proven to be good candidates for removing contaminations from wastewater efficiently and continuously. Inorganic porous materials possessing large surface area, and high chemical and thermal stability are excellent adsorbents for organic contaminants. However, a major shortfall of the inorganic porous membranes is that they are usually fragile. Here we demonstrate flexible SiO2-TiO2 composite porous nanofibrous membranes fabricated via electrospinning technique for efficient water purification. The composite membranes exhibit high adsorption capacity and permeability in the purification test with methylene blue solution based on their hierarchical porous structure and ultrafast wettability, and can be easily recycled by calcination. Such properties, integrated with the membrane fabrication process that is energy-efficient, low cost and easy to scale-up, will facilitate their practical application in the removal of organic pollutants. This journal is © 2013 The Royal Society of Chemistry.

Gu H.,Harbin Institute of Technology | Bi L.,Jilin University | Fu Y.,Harbin Institute of Technology | Wang N.,Harbin Institute of Technology | And 2 more authors.
Chemical Science | Year: 2013

Reversibly fluorescent switchable materials have important applications in the fields of ultrahigh-density optical data storage, molecular switches, logic gates, molecular wires, optical/electronic devices, sensors, bioimaging and so on. Some systems have been developed based on smart luminescent polymers and organic photoswitchable molecules. However, the use of such materials for practical applications is dramatically restricted by their intrinsic drawbacks such as low ON/OFF ratios, irreversibility and poor environmental resistance. An imperative challenge toward real applications is to design and fabricate photoluminescence switching devices with high on/off contrast and fast response time, and especially to obtain multicolored systems, in which the photoluminescence wavelength can be easily tuned in the visible region. Here we report the first inorganic example of a multicolored photoluminescence switching system by controlling the organization of crown-type polyoxometalates (POMs) and CdSe@CdS core-shell quantum dots (QDs) into the layer-by-layer (LBL) nanostructures. The photoluminescence of this system can be switched on and off reversibly upon application of step potentials for different redox states, owing to the energy transfer between reduced POMs and QDs. This system displays a quick response (off 17 s, on 38 s), high on/off contrast (∼91%), good cycling performance (the modulation ratio is only decreased by 19% after 200 cycles) and also has the advantage of low power consumption. Furthermore, reversible four-state fluorescence switching is realized by integrating different-sized QDs in one multifunctional system. This journal is © 2013 The Royal Society of Chemistry.

Lu S.,Jilin University | Lu S.,Beijing Computational Science Research Center | Wang Y.,Jilin University | Liu H.,Jilin University | And 3 more authors.
Nature Communications | Year: 2014

Surfaces of semiconductors are crucially important for electronics, especially when the devices are reduced to the nanoscale. However, surface structures are often elusive, impeding greatly the engineering of devices. Here we develop an efficient method that can automatically explore the surface structures using structure swarm intelligence. Its application to a simple diamond (100) surface reveals an unexpected surface reconstruction featuring self-assembled carbon nanotubes arrays. Such a surface is energetically competitive with the known dimer structure under normal conditions, but it becomes more favourable under a small compressive strain or at high temperatures. The intriguing covalent bonding between neighbouring tubes creates a unique feature of carrier kinetics (that is, one dimensionality of hole states, while two dimensionality of electron states) that could lead to novel design of superior electronics. Our findings highlight that the surface plays vital roles in the fabrication of nanodevices by being a functional part of them. © 2014 Macmillan Publishers Limited.

HONG KONG, Dec. 28, 2016 /PRNewswire/ -- Jebsen Group (Jebsen), a regional leader in marketing and distribution of premium products across Greater China, has recently released its Corporate Social Responsibility (CSR) Report 2016, which marks the 8th consecutive year that Jebsen has published its annual CSR report since 2009. It summarises Jebsen's innovative and effective practices in CSR management, business partnerships, environmental conservation, staff well-being, and philanthropy in 2015 across its diverse business units. With clearly established objectives and the Group's strong commitment in CSR, the programmes have taken economic, social and environmental considerations into the company's strategic development and operations. Jebsen's business growth has been successfully achieved, while expanding its efforts in various aspects of CSR from environment conservation, staff well-being to philanthropy. With a strong focus on the betterment of society, Jebsen's invested HKD 4.5 million in CSR activities in 2015. A total of 62 philanthropic activities were organised, garnering a total attendance of 898 people/times and raising HKD 250,000 in funds. By the end of 2015, Project Morning Star, a philanthropic initiative launched by Jebsen in partnership with ORBIS in 2011, has benefited over 1.2 million ophthalmic patients in rural China in its first five-year plan thanks to donations of over RMB 5.15 million made by the Group. Due to the tremendous achievements and impact over the first five years of this programme, the next five-year plan was launched in October 2016. More than a million people are expected to benefit from it, with Jebsen donating RMB 7.4 million between 2016 and 2020. Apart from Project Morning Star, Jebsen's commitment to caring for the underprivileged is also reflected in its Life is Art programme. Launched in 2014 in Hong Kong, Shanghai, Beijing and Guangzhou, this innovative programme focuses on caring for children with autism and children from migrant families, with the Shutterbug Club, Art Jamming Class and Djembe Drum Class as some of its major activities. Through the workshops, outdoor photographic exploration, DIY album creation and mini galleries, the Shutterbug Club provides the children with the opportunity to observe the world through a different lens and learn about colour and beauty. On the other hand, by organising Djembe Drum Class, teaching music and rhythm to the autistic children and providing them the opportunity to perform at music concerts and at Jebsen's annual dinner party, the programme harnesses their creativity and increases their confidence through music. In the second half of 2015, more than 80 Jebsen employees participated in these programmes to show their love for the children. Jebsen has also continued its support to education in order to cultivate the creativity, commitment and potential of students in universities. Jebsen will donate RMB 1 million in total over 5 years, from 2015 till 2019, to Nankai University for the second phase of the Nankai- Jebsen Education Fund, awarding outstanding students and teachers achieving excellent performance. Jebsen Group also cooperated with Jilin University in 2015, marking the third year of a partnership that seeks to nurture future business leaders through the means of a summer internship programme and insightful lectures. In Hong Kong, the Jebsen Educational Foundation Scholarship has supported more than 400 students over the past 20 years at The Hong Kong University of Science and Technology. Jebsen considers the well-being of its staff to be a key priority, and recognises employees to be one of its most valuable assets. Driven by its Employer Value Proposition (EVP) - "Success Breeds Success", the Group enhanced the communication with staff by launching "Jebsen Heroes" to highlight the staff's success stories within the Group and share their achievements. In terms of staff development, the Group has developed a Career Pathing Framework and continued training programmes to support employees in their career development. In 2016, Jebsen invested HKD 3.5 million in staff training, and the total training productivity was 2,130 person-times or 14,732 hours. Advocating a positive work and life attitude, the Group organised a series of staff engagement activities to foster happier minds and healthier bodies, such as wellness seminars and exercises to guide employees to maintain their physical and mental wellness. Environmental conservation is another core area of Jebsen's CSR endeavours as it aims to strengthen sustainable development. In 2015, emissions of the Jebsen Group totalled 8,772.85 tonnes of CO2-e, with carbon intensity having decreased by 10% compared to the 2009 baseline level. Meanwhile, Jebsen continues to invest in two climate friendly projects, and purchased 7207.74 tonnes of carbon credit to achieved carbon neutrality for three years in a row. To promote green and healthy living, Jebsen offers consumers a variety of green products and services including home and building products, water purifiers, etc. Internally, Jebsen launched the "Green Office Solution", encouraging staff to reduce printing, using recyclable paper, saving water and electricity. As a Diamond Member of WWF Corporate Membership Program (CMP) in Hong Kong since 2000, Jebsen proudly participated in the Earth Hour event for the eighth consecutive year, when all non-essential lights, neon signs, billboards and computers at Jebsen locations across the region were turned off for an hour during the global event. As a company deeply rooted in the Greater China region for the past 120 years, Jebsen has been awarded seven corporate social responsibility awards in 2015 which recognise its continuous active initiatives in philanthropy, staff well-being and environment conservation. "Grounded by its core values of Commitment, Excellence, Responsibility, Recognition, and Trust, Jebsen will expand its efforts in contributing to the communities and sustain innovation and adaptiveness to market changes," said Mr Helmuth Hennig, Group Managing Director of Jebsen. For more details, please click below links to download Jebsen CSR Report 2016. Founded in 1895, Jebsen Group is a focused marketing and distribution organisation. With a long, unique established presence and deep understanding of Mainland China, Hong Kong, Macau and Taiwan, the Jebsen Group is committed to supporting our partners' needs in building market demand, generating and supporting sales, and serving as an important link to customers throughout the region.  With a broad spectrum of consumer, beverage, industrial, and motors products, Jebsen offers some 200 of the world's leading products extensive local market access with a high degree of specialisation. Outside the region, the Jebsen Group enjoys close ties with sister companies in Australia, South East Asia, Denmark, Germany, Middle East and the United States. For more information, visit and Jebsen Facebook page (, or follow us on Sina Weibo (, WeChat (id: jebsen1895) and LinkedIn (id: jebsen group).

News Article | December 9, 2015

Understanding and tailoring materials’ properties usually requires trial and error, and a bit of luck. But, as a special issue of Computational Materials Science [112, Part B, 405-546, Computational Materials Science in China.] shows, the latest generation of computation techniques and new algorithms can now model novel materials and explore existing ones better than ever before. China is embracing these new possibilities, making fast progress over the last decade as access to computation resources has become more widespread, according to Xingao Gong of Fudan University. The university is home to a Key Laboratory for Computational Physical Sciences, which has over the last five years successfully used computational tools to clarify long-held misunderstandings about the structure and properties of quaternary semiconductors tagged for future solar cells. “The profile of computational materials science as a discipline has been rising quickly in China over the last few years,” adds Editor-in-Chief, Professor Susan Sinnott of The Pennsylvania State University. “So this is an ideal time to highlight some of the best work in the field that is being carried out there.” Exploring the electronic and magnetic properties of materials theoretically begins with a simple model. By considering a few tens or hundreds of atoms at a time, computational methods can calculate properties that are scalable to larger dimensions. These basic models can be finely tuned to improve accuracy. At the University of Science and Technology of China, for example, Lixin He and colleagues are using atomic orbitals as the basic unit for ab initio electronic structure calculations of silicon, group IV and III-V semiconductors including technologically important GaAs and GaN, as well as alkali and 3d transition metals. Focusing on orbital physics can be a helpful tactic in unpicking the novel electronic and magnetic behavior of transition metal oxides, which are a platform for many functional devices, according to Hua Wu at Fudan University. The combination of charge, spin, and orbital degrees of freedom in these materials leads to unusual – and useful – effects such as colossal magnetoresistance and multiferroicity. First principles calculations based on density functional theory (DFT), where quantum mechanical equations determine the density of electrons, are proving effective and versatile in understanding the new generation of planar materials, such as graphene, silicene, and boron nitride. Despite being well known for decades, DFT has been refined in recent years so it can now be used to tailor the physical properties of 2D materials for applications. DFT can also help unravel the science behind exotic materials like topological insulators, which have an insulating core but surface conducting electrons. Researchers at Beijing Institute of Technology are using this approach to explore such fantastic phenomena as these in solid materials that would be difficult to comprehend by other means. Likewise, modeling is effective when it comes to identifying and assessing materials for extreme environments. A group at Beihang University is using DFT to identify materials able to withstand the extreme temperatures and irradiation levels inside thermonuclear reactors. Taking a different approach to models, meanwhile, can yield new insights. A group at Jilin University, for example, has devised a computational method based on a ‘swarm intelligence’ algorithm inspired by natural systems such as ant colonies, bee swarms, and flocks of birds. The self-improving approach works particularly well with atomic and molecular clusters, nanoparticles, and 3D bulk materials. “I am very excited to see that young scientists in China now have a strong interest in developing new algorithms and first principles approaches based on local atomic orbitals,” says Gong. The rise of computational methods to understand materials behaviors and properties, and drive new materials’ discovery, has been particularly impressive in China, agrees Baptiste Gault, senior publisher at Elsevier. “It is very timely to provide an overview of the state-of-the-art here and Computational Materials Science is the preeminent forum.” This special issue is published in Computational Materials Science- 112, Part B, 405-546 "Computational Materials Science in China". To find out more about each article included within this special issue, please follow the below links: The novel electronic and magnetic properties in 5d transition metal oxides system First-principles investigations on the Berry phase effect in spin–orbit coupling materials Recent progresses in real-time local-basis implementation of time dependent density functional theory for electron–nucleus dynamics Modeling and simulation of helium behavior in tungsten: A first-principles investigation Recent advances in computational studies of organometallic sheets: Magnetism, adsorption and catalysis Tailoring physical properties of graphene: Effects of hydrogenation, oxidation, and grain boundaries by atomistic simulations

To bring out the essentials of high-frequency asymptotic scattering theories and their applications in numerical modeling and imaging of geophysical fields, we give a brief overview of the corresponding research histories and the state-of-the-art. Also, we present some new developments that we have achieved in the last five years in the investigation of the high-frequency asymptotic scattering theories. Considering some problems in the literature, we first give a brief review of the basic concepts and formulas in the scattering theory; and reaffirm and underline the mathematical physics intensions of the concepts and formulas. Next, we give an overview of the research history and the state-of-the-art of the high-frequency asymptotic scattering theories, and make some comments on some related topics. Moreover, we present some new developments that we have achieved in the last five years in the corresponding studies, including the quasi-analytical approximation of the surface integral equation of the scattered waves, the generalized Beam-Born and Beam-Rytov type approximations, and so on. Finally, we give some prospects for the road ahead of the development of the high-frequency asymptotic scattering theories themselves and their application in numerical modeling and imaging of geophysical fields. Not only in history but also at present, play the asymptotic scattering theories an irreplaceable role in numerical modeling and imaging of geophysical fields, especially in migration of reflection seismic data and in full waveform inversion. In author's point of view, the further development of the high-frequency asymptotic scattering theories depends on the investigation of the Green's function. Along with the uninterrupted deep-going of the corresponding studies, the high-frequency asymptotic scattering theories will play a much more important role in numerical modeling and imaging of geophysical fields in future. © 2016, Science Press. All right reserved.

Fei T.,Jilin University | Jiang K.,Jilin University | Zhang T.,Jilin University
Sensors and Actuators, B: Chemical | Year: 2014

Photoluminescent (PL) sensing is a common method for the detection of trace nitroaromatic explosive 2,4,6-trinitrotoluene (TNT). In this work, a red emissive phosphorescent iridium(III) complex was synthesized and used for TNT sensing. The obtained iridium(III) complex is highly emissive, and the PL response of the complex in solution toward TNT was researched by examining the steady state emission intensity to the concentration of TNT. Efficient PL quenching was obtained when TNT was added to the detection solution. The long excited-state lifetime of obtained phosphorescent complex is beneficial for interaction with TNT molecules. In addition, suitable matching of the lowest unoccupied molecular orbital (LUMO) levels of the iridium(III) complex with TNT also benefits the electron transfer from the complex to TNT molecules and enhances the PL quenching. As a small molecular material, the obtained phosphorescent complex shows comparable PL quenching efficiency to TNT with reported conjugated polymers. © 2014 Elsevier B.V.

Fei T.,Jilin University | Jiang K.,Jilin University | Liu S.,Jilin University | Zhang T.,Jilin University
Sensors and Actuators, B: Chemical | Year: 2014

Nanoporous polymer based on divinylbenzene was synthesized by radical polymerization with a solvothermal route. The nanoporous characteristic of the resultant polymer poly(divinylbenzene) (PDVB) was determined by a series of characterizations. The hydrophobic porous polymer was used as the host to prepare composited humidity sensitive materials. Different levels of LiCl were loaded into the nanoporous polymer and their humidity sensing properties were researched. Humidity sensitivities of the composites were greatly improved by LiCl loading compared with pure PDVB. The sensor based on 5 wt% LiCl/PDVB showed the best sensing properties to relative humidity (RH). The impedance of the optimum sensor changed three orders of magnitude over the whole humidity range, with a good linearity and rapid response. The mechanism by the complex impedance plots suggests the protons are the domination carrier in low humidities and ions (Li+ and Cl-) in a high humidity range. The results demonstrate nanoporous polymers are a new kind of promising materials for humidity sensors. © 2013 Elsevier B.V. All rights reserved.

Zhang Y.,Jilin University | Sun J.,Jilin University
ACS Nano | Year: 2015

In this study, we demonstrate multilevel and multicomponent layer-by-layer (LbL) assembly as a convenient and generally applicable method for the fabrication of nanofibrillar films by exploiting the dynamic nature of polymeric complexes. The alternate deposition of poly(allylamine hydrochloride)-methyl red (PAH-MR) complexes with poly(acrylic acid) (PAA) produces nanofibrillar PAH-MR/PAA films, which involves the disassembly of PAH-MR complexes, the subsequent assembly of PAH with PAA, and the PAA-induced assembly of MR molecules into MR nanofibrils via a π-π stacking interaction. The aqueous solution of weak polyelectrolyte PAA with a low solution pH plays an important role in fabricating nanofibrillar PAH-MR/PAA films because proton transfer from acidic PAA to MR molecules induces the formation of MR nanofibrils. The generality of the multilevel and multicomponent LbL assembly is verified by alternate assembly of complexes of 1-pyrenylbutyric acid (PYA) and PAH with PAA to fabricate PAH-PYA/PAA films with organized nanofibrillar structures. Unlike the traditional static LbL assembly, the multilevel and multicomponent LbL assembly is dynamic and more flexible and powerful in controlling the interfacial assembly process and in fabricating composite films with sophisticated structures. These characteristics of multilevel and multicomponent LbL assembly will enrich the functionalities of the LbL-assembled films. © 2015 American Chemical Society.

Su X.,Jilin University | Xu W.,Jilin University | Du S.,Jilin University
Journal of Water Supply: Research and Technology - AQUA | Year: 2014

Artificial recharge is becoming one of the most important ways to deal with water shortage and induced environmental geological problems, but it also brings potential groundwater contaminant risks, especially under extreme weather conditions. A classic method, DRASTIC, and groundwater flow simulation model have been used to analyze the response of groundwater vulnerability to artificial recharge under extreme weather conditions. The results show that a simultaneously abundant year and scarce year of the local area and the Han River Basin are 7.46 and 6.60%, respectively. The quantities of artificial recharge water would be 8.72 × 104 m3/a and 4.64 × 104 m3/a, respectively. Five scenarios with extreme weather conditions were discussed. The groundwater vulnerability would not change a great deal without extreme conditions under artificial recharge. Under extreme abundant conditions, the induced groundwater level lowering would making the depth of groundwater level increase, and the vulnerability would be lower. Under extreme abundant conditions, the decreased depth of groundwater level and increased net recharge made the vulnerability increase obviously, and the low vulnerability area was converted into the moderate and high vulnerability areas. More attention should be paid to the quality of recharged water and monitoring schemes should be carried out around the infiltration field. © IWA Publishing 2014.

Wang L.,Jilin University | Wang K.,Jilin University | Zou B.,Jilin University | Ye K.,Jilin University | And 2 more authors.
Advanced Materials | Year: 2015

An organic crystal adopts a molecular packing that can be readily perturbed by external stresses like tensile forces, isotropic pressure, and anisotropic pressure through mechanical smashing, grinding, and compressing, respectively. As a result, the crystals display mechanoluminescence (ML) in response to different mechanical stimuli. The present study provides a model in which three distinct MLs are combined into one organic material. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Tian H.,Jilin University | Yuan R.,Chongqing University | Zhao Y.,Chongqing University
Dianwang Jishu/Power System Technology | Year: 2013

To improve the reliability evaluation efficiency of distribution network containing distributed generation (DG), a network partition-based fault recovery strategy is proposed. Considering the influence of DG on distribution network reliability, a probability distribution model for the reliability of distribution network containing DG and corresponding algorithm are put forward, thus the defect of traditional expectation indices that measure system risk only in the meaning of probabilistic mean values is remedied. Based on the thinking of partitioning of distribution network, the reliability indices of distribution network are characterized by random function in system level and nodal hierarchies, and combining with non-parametric kernel density estimation the probability distribution calculation of random function expression for reliability indices is implemented. Simulation results of RBTS-BUS6 system show that the proposed method is effective.

Zhao Y.,Jilin University | Zhao Y.,New York State Institute for Basic Research in Developmental Disabilities | Gong C.-X.,New York State Institute for Basic Research in Developmental Disabilities
Cellular and Molecular Neurobiology | Year: 2014

Chronic cerebral hypoperfusion (CCH) is a common consequence of various cerebral vascular disorders and hemodynamic and blood changes. Recent studies have revealed an important role of CCH in neurodegeneration and dementia, including vascular dementia and Alzheimer’s disease (AD). This article reviews the recent advances in understanding CCH-induced neurodegeneration and AD-related brain pathology and cognitive impairment. We discuss the causes and assessment of CCH, the possible mechanisms by which CCH promotes Alzheimer-like pathology and neurodegeneration, and animal models of CCH. It appears that CCH promotes neurodegeneration and AD through multiple mechanisms, including induction of oxidative stress, Aβ accumulation and aggravation, tau hyperphosphorylation, synaptic dysfunction, neuronal loss, white matter lesion, and neuroinflammation. Better understanding of the mechanisms of CCH will help develop therapeutic strategies for preventing and treating neurodegeneration, including sporadic AD and vascular dementia, caused by CCH. © 2014, Springer Science+Business Media New York.

Zheng J.H.,Jilin University | Jiang Q.,Jilin University | Lian J.S.,Jilin University
Applied Surface Science | Year: 2011

Flower-like ZnO nanorods have been synthesized by heating a mixture of ZnO/graphite powders using the thermal evaporation and vapor transport on Si (1 0 0) substrates without any catalyst. The structures, morphologies and optical properties of the products were characterized in detail by using X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) and Raman spectroscopy. The synthesized products consisted of large quantities of flower-like ZnO nanostructures in the form of uniform nanorods. The flower-like ZnO nanorods had high purity and well crystallized wurtzite structure, whose high crystalline quality was proved by Raman spectroscopy. The as-synthesized flower-like ZnO nanorods showed a strong ultraviolet emission at 386 nm and a weak and broad yellow-green emission in visible spectrum in its room temperature photoluminescence (PL) spectrum. In addition, the growth mechanism of the flower-like ZnO nanorods was discussed based on the reaction conditions. © 2010 Elsevier B.V. All rights reserved.

Sun H.,Jilin University
Lecture Notes in Electrical Engineering | Year: 2016

The rapid development of science and technology makes the mouse become the most commonly used product life and work, but also the most frequent computer equipment, so users gradually the use of mouse proposed more requirements, including comfortable operation, flexible moving and accurate positioning, operation comfort discomfort the most attention. The fatigue caused by long time and high frequency use of mouse is known as the mouse hand. The disease has exerted adverse effect on people’s life and work. In the paper, based on the experimental data of fatigue of using mouse, in-depth analysis was conducted on the bone and meridian of the arm using traditional mouse as well as the wrist force. On the basis of the man–machine factors, the traditional mouse was improved in the design. Besides, the optimization scheme that could reflect mouse comfort and effectively avoid mouse hand was put forward. © Springer Science+Business Media Singapore 2016.

A poly(butyl methacrylate-co-ethyleneglyceldimethacrylate) (poly(BMA-EDMA)) monolithic column was prepared with in situ polymerization method and modified with allylamine-β-cyclodextrin (ALA-β-CD) and nano-cuprous oxide (Cu2O). A polymer monolith microextraction method was developed with the modified monolithic column for the preconcentration of polychlorinated biphenyls combined with gas chromatography-electron capture detector. Various parameters affecting the extraction efficiency were investigated and optimized. Under the optimum experimental conditions, we obtained acceptable linearities, low limits of detection, and good intra-day/inter-day relative standard deviations. Because of the hydrophobic properties of β-CD and the porous nano structure of Cu2O, the enrichment capacity of the poly(BMA-EDMA) monolithic column was significantly improved. The extraction efficiency followed the order: poly(BMA-EDMA-ALA-β-CD-Cu2O)>poly(BMA-EDMA-ALA-β-CD)>poly(BMA-EDMA)>direct GC analysis. When applied to the determination of polychlorinated biphenyls in wine samples, low limits of detection (0.09ngmL-1) were obtained under the preoptimized conditions (sample volume 1.0mL, sample flow rate 0.1mLmin-1, eluent volume 0.1mL, and eluent flow rate 0.05mLmin-1). In addition, the present method was employed to determine polychlorinated biphenyls in red wine samples and the accuracy was assessed through recovery experiments. The obtained recovery values were in the range of 78.8-104.1% with relative standard deviations less than 9.0%. © 2014 Elsevier B.V.

Bai Z.K.,Jilin University
Journal of molecular histology | Year: 2013

The aim of this study was to investigate the differential expression and regulation of Runt-related transcription factor 3 (Runx3) in mouse uterus during early pregnancy and its regulation by steroid hormones using in situ hybridization. There was a low level of the Runx3 mRNA expression in the mouse uterus on days 1-4 of pregnancy. On day 5 when embryo implanted, Runx3 mRNA signal was obviously observed in the stromal cells surrounding the implanting blastocyst. From day 6 to 8 of pregnancy, Runx3 mRNA was highly expressed in the decidual cells and mesometrial decidual beds. Similarly, Runx3 mRNA was strongly expressed in decidualized cells under artificial decidualization. Compared with the delayed uterus, a high level of Runx3 mRNA signal was detected in the uterus with activated implantation. In the ovariectomized mouse uterus, estrogen could induce the expression of Runx3, while progesterone had no effects. These results suggest that Runx3 may play an important role during mouse implantation and decidualization. Estrogen can induce the expression of Runx3 in the ovariectomized mouse uterus.

Lin L.,Dalian Polytechnic University | Zhai S.-R.,Dalian Polytechnic University | Xiao Z.-Y.,Dalian Polytechnic University | Song Y.,Dalian Polytechnic University | And 2 more authors.
Bioresource Technology | Year: 2013

In continuation of previous work on utilizing rice husks, this study aimed to prepare mesoporous activated carbons using residues of sodium hydroxide-pretreated RHs, and then examine their dye adsorption performance. The influences of the activation temperature and activation time on the surface area, pore volume, and pore radius of the activated carbon were investigated based on nitrogen adsorption/desorption isotherms and transmission electron microscopy. The adsorptive behavior of the mesoporous activated carbons obtained under optimum preparation conditions was evaluated using methyleneblue as the model adsorbate. The adsorption kinetics was studied by pseudo-first-and pseudo-second-order models, and the adsorption isotherms were studied by Langmuir and Freundlich models. The pseudo-second-order model and Langmuir isotherm were found to fit well the adsorption characteristics of the as-prepared mesoporous activated carbons. Thermodynamic data of the adsorption process were also obtained to elucidate the adsorption thermo-chemistry between the activated carbons produced from NaOH-pretreated RHs and MB molecules. © 2013 Elsevier Ltd.

Zhang Y.,Jilin University | He Z.,Jilin University | Li G.,Jilin University
Talanta | Year: 2010

A novel amphiphile containing two functional groups of both naphthalene and boronic acid, 2-(hexadecyloxy)-naphthalene-6-boronic acid (HNBA), has been synthesized. Scanning electron microscopy (SEM) indicated the formation of bilayer vesicles in the ethanol/water solution (Φ = 0.6). Differential scanning calorimetry (DSC) established the presence of crystal-to-liquid crystal transition at 63.36 °C. The vesicular fluorescence properties upon binding with carbohydrates have been studied in ethanol/water buffer at pH 7.4. Addition of saccharides to the vesicular solution, the fluorescent intensities of naphthalene in HNBA vesicles centered at 348 nm decreased dramatically with increasing concentration of saccharides. The change tendency of fluorescent intensities of the HNAB vesicles with concentration of saccharides followed in the order of fructose > galactose > maltose > glucose. The pH profiles of the fluorescence intensity were studied in the absence and in the presence of sugars. Also, the urine sample induced spectral changes of the HNBA vesicles were studied. These results suggest that the HNBA vesicles may be developed as a continuous monitoring and implantable fluorescence vesicular sensor, which might be applied in the practical field. © 2010 Elsevier B.V. All rights reserved.

Zhang F.,Jilin University | Zou X.,Jilin University | Gao X.,Jilin University | Fan S.,Jilin University | And 3 more authors.
Advanced Functional Materials | Year: 2012

Hydrogen-based energy is a promising renewable and clean resource. Thus, hydrogen selective microporous membranes with high performance and high stability are demanded. Novel NH 2-MIL-53(Al) membranes are evaluated for hydrogen separation for this goal. Continuous NH 2-MIL-53(Al) membranes have been prepared successfully on macroporous glass frit discs assisted with colloidal seeds. The gas sorption ability of NH 2-MIL-53(Al) materials is studied by gas adsorption measurement. The isosteric heats of adsorption in a sequence of CO 2 > N 2 > CH 4 -H 2 indicates different interactions between NH 2-MIL-53(Al) framework and these gases. As-prepared membranes are measured by single and binary gas permeation at different temperatures. The results of singe gas permeation show a decreasing permeance in an order of H 2 > CH 4 > N 2 > CO 2, suggesting that the diffusion and adsorption properties make significant contributions in the gas permeation through the membrane. In binary gas permeation, the NH 2-MIL-53(Al) membrane shows high selectivity for H 2 with separation factors of 20.7, 23.9 and 30.9 at room temperature (288 K) for H 2 over CH 4, N 2 and CO 2, respectively. In comparison to single gas permeation, a slightly higher separation factor is obtained due to the competitive adsorption effect between the gases in the porous MOF membrane. Additionally, the NH 2-MIL-53(Al) membrane exhibits very high permeance for H 2 in the mixtures separation (above 1.5 × 10 -6 mol m -2 s -1 Pa -1) due to its large cavity, resulting in a very high separation power. The details of the temperature effect on the permeances of H 2 over other gases are investigated from 288 to 353 K. The supported NH 2-MIL-53(Al) membranes with high hydrogen separation power possess high stability, resistance to cracking, temperature cycling and show high reproducibility, necessary for the potential application to hydrogen recycling. Continuous NH 2-MIL-53(Al) metal-organic framework (MOF) membranes are prepared successfully on macroporous glass frit discs assisted with colloidal seeds to be evaluated for hydrogen gas separation. As-prepared membrane is studied by single and binary gas permeation of H 2, CH 4, N 2 and CO 2 at different temperatures. The supported NH 2-MIL-53(Al) membranes exhibit high permeance and high selectivity, which result in a very high separation power. The robust membranes with high performance are expected in potential applications for hydrogen recycling. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chan J.G.Y.,University of Sydney | Bai X.,Jilin University | Traini D.,University of Sydney
Expert Opinion on Drug Delivery | Year: 2014

Introduction: Tuberculosis (TB) remains rampant throughout the world, in large part due to the lengthy treatment times of current therapeutic options. Rifapentine, a rifamycin antibiotic, is currently approved for intermittent dosing in the treatment of TB. Recent animal studies have shown that more frequent administration of rifapentine could shorten treatment times, for both latent and active TB infection. However, these results were not replicated in a subsequent human clinical trial. Areas covered: This review analyses the evidence for more frequent administration of rifapentine and the reasons for the apparent lack of efficacy in shortening treatment times in human patients. Inhaled delivery is discussed as a potential option to achieve the therapeutic effect of rifapentine by overcoming the barriers associated with oral administration of this drug. Avenues for developing an inhalable form of rifapentine are also presented. Expert opinion: Rifapentine is a promising active pharmaceutical ingredient with potential to accelerate treatment of TB if delivered by inhaled administration. Progression of current fundamental work on inhaled anti-tubercular therapies to human clinical trials is essential for determining their role in future treatment regimens. While the ultimate goal for global TB control is a vaccine, a short and effective treatment option is equally crucial. © 2014 Informa UK, Ltd.

Xue S.,Jilin University | Yao L.,Jilin University | Shen F.,Jilin University | Gu C.,Jilin University | And 2 more authors.
Advanced Functional Materials | Year: 2012

Highly efficient and fully solution-processed white organic light-emitting diodes (WOLEDs) based on fluorescent small molecules and a polar conjugated polymer as electron-injection material are reported. The emitting layer in the WOLEDs is a blend of new blue-, green-, and red-fluorescent small molecules, with a blending ratio of 100:0.4:0.8 (B/G/R) by weight, and a methanol/water soluble conjugated polymerpoly[(9,9-bis(30-(N,N-dimethylamino)propyl)-2,7- fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) acts as the electron-injection layer (EIL). All the organic layers are spin-coated from solution. The device exhibits pure white emission with a maximum luminous efficiency of 9.2 cd A -1 and Commission Internationale d'Eclairage Coordinates of (0.35, 0.36). PFN acting as the EIL material plays a key role in the improvement of the device performance when used in solution-processed small-molecule WOLEDs. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Liu S.,Jilin University | Na W.,Jilin University | Pang S.,Jilin University | Su X.,Jilin University
Biosensors and Bioelectronics | Year: 2014

In this paper, we have developed a simple and rapid method for the detection of Pb2+ based on the DNA sequence capped CdS quantum dots (QDs). We utilized the designed guanine (G)-rich DNA sequence (PS2.M) as a coating reagent to synthesize the DNA-capped CdS QDs. The designed G-rich DNA sequence PS2.M can bind with hemin to form G-quadruplex/hemin complex with K+, accompanied by the fluorescence quenching of CdS QDs via the photoinduced electron transfer. Pb2+ can induce conformational changes in the G-quadruplex/hemin complex to release the hemin molecules, so the quenched fluorescence of CdS QDs could be recovered. Therefore, the new fluorescent analysis system could be applied for the detection of Pb2+ based on the label-free DNA sequence capped CdS QDs. © 2014 Elsevier B.V.

Zhang H.,Jilin University | Zhang H.,Karolinska University Hospital | Wu L.-M.,Jilin University | Wu J.,Jilin University
Mediators of Inflammation | Year: 2011

Apolipoprotein E (apoE) is a multifunctional glycosylated protein characterized by its wide tissue distribution. Despite its importance in lipid transport and atherosclerosis pathogenesis, apoE is associated with neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson disease, and autoimmune disorders such as multiple sclerosis and psoriasis. Among others, the role of apoE in modulating inflammation and oxidation is crucial in elucidating the risk factors of the above diseases since the function of apoE is closely linked with both proinflammatory and antiinflammatory cytokines. Moreover, apoE modulates inflammatory and immune responses in an isoform-dependent manner. Correspondingly, inflammatory cytokines can either upregulate or downregulate the production of apoE in various tissue types. However, studies on the interactions between apoE and cytokines occasionally yield conflicting results, highlighting the complex roles of apoE and cytokines in various disorders. The present paper summarizes the current knowledge about the cross-talk between apoE and cytokines, with emphasis on the effects of apoE on the Th1/Th2 balance. Copyright © 2011 Hongliang Zhang et al.

Sun P.D.,Jilin University
Zhonghua wei chang wai ke za zhi = Chinese journal of gastrointestinal surgery | Year: 2011

To study the feasibility and influence of vagus nerve preservation in radical operation for proximal gastric cancer. Thirty-two patients with early or T2 cardia cancer from May 2007 to May 2009 were enrolled and randomized into two groups, i.e. vagus nerve preservation group(n=16) and control group(n=16). Two groups were compared with regard to operative time, anastomotic fistula, digestive discomforts, body weight, survival rate, findings on gastroscope and abdominal ultrasonography. There were no statistically significant differences between the two groups in operative time (2.8 vs. 2.5 h), postoperative complications rate (25.0% vs. 31.3%). No recurrence or mortality was observed after one-year follow-up. However, patients who underwent vagus nerve preservation had less postprandial discomforts(3 vs. 12 cases), bile reflux(3 vs. 10 cases), atrophic gastritis(1 vs. 9 cases), gallstones(1 vs. 8 cases), body mass index, and diarrhea(P<0.05). For patients with early gastric cancer, preservation of the vagus nerve during radical gastrectomy results in less complications and does not compromise patient survival.

Yuan H.,Jilin University | Wang K.,Jilin University | Yang K.,CAS Shanghai Institute of Applied Physics | Liu B.,Jilin University | Zou B.,Jilin University
Journal of Physical Chemistry Letters | Year: 2014

Mechanochromic materials with aggregation-induced enhanced emission (AIEE) characteristic have been intensively expanded in the past few years. In general, intermolecular interactions invariably alter photophysical processes, while their role in the luminescence properties of these AIEE-active molecules is difficult to fully recognize because the pressurized samples possess amorphous nature in many cases. We now report the high-pressure studies on a prototype AIEE-active molecule, tetraphenylethene, using diamond anvil cell technique with associated spectroscopic measurements. An unusual pressure-dependent color, intensity, and lifetime change in tetraphenylethene has been detected by steady-state photoluminescence and time-resolved emission decay measurements. The flexible role of the aromatic C-H⋯π and C-H⋯C contacts in structural recovery, conformational modification, and emission efficiency modulation upon compression is demonstrated through structure and infrared analysis. SECTION: Spectroscopy, Photochemistry, and Excited States © 2014 American Chemical Society.

Du Y.,Jilin University
Lecture Notes in Electrical Engineering | Year: 2016

This research applies the theory of human-machine-environment system engineering, using the measurement method to analyze the relationship between the user and the various components of the office chair in the sedentary condition. The measurement and analysis of the numerical value of the Chinese office crowd, find the basic design criteria of the modern office chair, which is seat height, seat width, seat depth, seat angle, seat back, and seat armrest. The research aims at optimizing modern office chair design and combining with human-machine-environment system engineering to make the design more scientific and reasonable. © Springer Science+Business Media Singapore 2016.

Yu Y.,Jilin University | Wu B.,Jilin University | Lim C.W.,City University of Hong Kong
International Journal of Mechanical Sciences | Year: 2012

This paper analyzes the electromechanical post-buckling response of an axially stressed clamped-clamped beam actuator subjected to a symmetric electrostatic field. Numerical solutions of the nonlinear integral-differential governing equation are first obtained by constructing the extended systems and applying the shooting method. The corresponding analytical approximate solutions are then established by combining Newton linearization with Galerkins method. In contrast to the classical Galerkins method, the linearization is performed prior to its application. This yields a set of linear algebraic equations instead of nonlinear algebraic equations, and hence analytical approximate solutions are established. These analytical approximate solutions show excellent agreement with numerical solutions from the shooting method, and they are valid for a wide range of beam-center deflection. The analytical approximate method presented here is simple in principle and it is easy to be implemented with the help of any symbolic computational software. © 2012 Elsevier Ltd. All rights reserved.

Pan L.L.,Jilin University | Li G.Y.,Jilin University | Su Y.C.,Jilin University | Lian J.S.,Jilin University
Polymer Degradation and Stability | Year: 2012

Ammonium polyphosphate (APP) and triphenyl phosphate (TPP) were added in a dicyclopentadiene (DCPD) modified unsaturated polyester resin (UPR) as intumescent flame retardant (IFR) and the combustion resistance effects were investigated. Flammability and thermal stability were investigated through limiting oxygen index (LOI) test and UL-94 vertical burning test and by using thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC). When 57.6 wt.% of the flame retardant was added, the LOI value increased from 20.9 to 27.2 and a V-0 rating in UL-94 test was obtained. The fire-resistant time reached to 26∼34 min. The TGA and DSC analyses showed that the char yield was increased by the introduction of APP and TPP system and decomposition of the phosphorous additives yielded strongly phosphoric acids which effectively promoted the cross-linking reaction during the burning process. So, a profound flame retardant effect was obtained as APP and TPP were added to the unsaturated polyester resin. © 2012 Elsevier Ltd. All rights reserved.

Pei Y.-C.,Jilin University
International Journal of Mechanical Sciences | Year: 2012

A rotating flexible annular micro-disk under thermoelastic coupling is modeled to investigate the thermoelastic damping in the rotating micro-disk in Microdrives. Transverse deflection of the micro-disk is considered as a function of both disk radial and circumferential coordinates, and its thermoelastic temperature increment is modeled by simultaneously involving disk thickness, radial and circumferential coordinates. Heat convection boundaries are assumed at disk top and bottom surfaces. System governing equations with the centrifugal stresses of disk rotation and thermoelastic coupling terms are discretized along disk radial direction by an annular finite element, and a quadratic eigenvalue problem is yielded to determine the thermoelastic damping. Mode shapes of the transverse deflection and temperature increment are presented, effects of disk rotation, surface convection and ambient temperature on natural frequency, frequency shift and thermoelastic damping are investigated. The maximum thermoelastic damping is obtained by optimizing disk thickness, inner radius and radial width. © 2012 Elsevier Ltd. All rights reserved.

Wu H.,Jilin University
Applied Mechanics and Materials | Year: 2013

According to inputting different combination of conditions so as to produce different impacts, software testing designs a large number of test cases. If the implementation of an overall test, due to the limit of the combination of conditions, it is difficult to carry out. In order to generate high quality test cases as early as possible to improve the efficiency of software testing, it is designed a generation tool of the automatic software testing case on orthogonal experimental design. For the test data, the use of that tool design test cases. The practice shows that a small number of test cases are generated, the error detection ability is strong, and it greatly improves the efficiency of software testing. © 2013 Trans Tech Publications Ltd, Switzerland.

Li A.,Jilin University
Faguang Xuebao/Chinese Journal of Luminescence | Year: 2012

We examine the absorption and dispersion properties of a weak probe field in a three-level lambda system closed by a microwave field. We find that, due to quantum interference in this closed-loop atomic system, the absorption and dispersion properties of a weak probe field depend on the relative phase of the applied fields. A large inversionless gain and a large index of refraction with zero absorption can be obtained by tuning the relative phase into proper values. In the case of three-photon off-resonance, the probe gain (absorption) exhibits periodically oscillatory behavior versus time.

Dai Q.Q.,Jilin University | Zhu Y.F.,Jilin University | Jiang Q.,Jilin University
Physical Chemistry Chemical Physics | Year: 2014

Grain boundaries (GBs) that inevitably appear in CVD-grown graphene affect the electronic properties of graphene-based nanomaterials. In this paper, we introduce 558 GB (composed of a pair of pentagons and one octagon alternately) into armchair graphene nanoribbons (AGNRs) and divide them into three groups in light of the end configurations of 558 GB at the ribbon edges. By using first-principles calculations, the variations of electronic and magnetic properties with two adjustable parameters W (ribbon widths) and NZ (the distances between 558 GBs) are systematically investigated for each group. The results show that different electronic and magnetic behaviors versus W and NZ are presented for varying end configurations of 558 GB, including nonmagnetic metals, ferromagnetic metals and nonmagnetic semiconductors. By introducing 558 GB into AGNRs, the impurity states that are completely contributed by 558 GB appear around the Fermi level. Furthermore, a ferromagnetic ordering on the two zigzag chains of 558 GB occurs for the ferromagnetic metals due to the spin splitting energy bands near the Fermi level. These unique electronic and magnetic properties of AGNRs with 558 GB would find their potential applications in electronic and spintronic devices. This journal is © the Partner Organisations 2014.

Gao N.,Jilin University | Li J.C.,Jilin University | Jiang Q.,Jilin University
Physical Chemistry Chemical Physics | Year: 2014

The geometric and electronic properties of silicene paired with a MoS 2 substrate are studied systematically by using density functional theory with van der Waals corrections. It is found that the nearly linear band dispersions can be preserved in the heterobilayers due to the weak interface interactions. Meanwhile, the band gap is opened because of the sublattice symmetry broken by the intrinsic interface dipole. Moreover, the band gap values could be effectively modulated under an external electric field. Therefore, a way is paved for silicene-MoS2 heterobilayers to be candidate materials for logic circuits and photonic devices. © 2014 the Partner Organisations.

Sun X.,Wayne State University | Wang Z.,Jilin University | Kadouh H.,Wayne State University | Zhou K.,Wayne State University
LWT - Food Science and Technology | Year: 2014

Chitosan films incorporated with various concentrations of gallic acid were prepared and investigated for antimicrobial, mechanical, physical and structural properties. Four bacterial strains that commonly contaminate food products were chosen as target bacteria to evaluate the antimicrobial activity of the prepared gallic acid-chitosan films. The incorporation of gallic acid significantly increased the antimicrobial activities of the films against Escherichia coli, Salmonella typhimurium, Listeria innocua and Bacillus subtilis. Chitosan films incorporated with 1.5 g/100 g gallic acid showed the strongest antimicrobial activity. It was also found that tensile strength (TS) of chitosan film was significantly increased when incorporating 0.5 g/100 g gallic acid. Inclusion of 0.5 g/100 g gallic acid also significantly decreased water vapor permeability (WVP) and oxygen permeability (OP). Microstructure of the films was investigated by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) and it was found that gallic acid was dispersed homogenously into the chitosan matrix. © 2013 Elsevier Ltd.

Bai Y.,Jilin University | Luo Q.,Jilin University | Liu J.,Jilin University
Chemical Society Reviews | Year: 2016

Proteins, as the elemental basis of living organisms, mostly execute their biological tasks in the form of supramolecular self-assemblies with subtle architectures, dynamic interactions and versatile functionalities. Inspired by the structural harmony and functional beauty of natural protein self-assemblies to fabricate sophisticated yet highly ordered protein superstructures represents an adventure in the pursuit of nature's supreme wisdom. In this review, we focus on building protein self-assembly systems based on supramolecular strategies and classify recent progress by the types of utilized supramolecular driving forces. Especially, the design strategy, structure control and the thermodynamic/kinetic regulation of the self-assemblies, which will in turn provide insights into the natural biological self-assembly mechanism, are highlighted. In addition, recently, this research field is starting to extend its interest beyond constructing complex morphologies towards the potential applications of the self-assembly systems; several attempts to design functional protein complexes are also discussed. As such, we hope that this review will provide a panoramic sketch of the field and draw a roadmap towards the ultimate construction of advanced protein self-assemblies that even can serve as analogues of their natural counterparts. © 2016 The Royal Society of Chemistry.

Li Y.,Jilin University | Yu J.,Jilin University
Chemical Science | Year: 2016

Since the launch of the Materials Genome Initiative by the US government in 2011, many computer techniques have been developed to predict the structures and properties of advanced materials, providing important guidance for laboratory experimentation and a promising new direction for future materials innovation. However, lots of inorganic materials are difficult for computers to process because of their complex three-dimensionally extended structures. Fortunately, many of these materials are built from well-defined stacking layer modules, and the stacking sequences of their layer modules unambiguously determine their three-dimensional structures. Such one-dimensional stacking sequence representation is naturally accessible for computer processing, easing the problems not only of structure elucidation, but also in the enumeration, evaluation, and screening of a large number of unknown materials with desired properties. More importantly, with the aid of various computational methods, we may reveal the relationship between the stacking sequences and the properties of these materials, which is a key prerequisite for function-led targeted synthesis. This Minireview covers the most recent progress in this emerging area. © The Royal Society of Chemistry 2016.

Errea I.,Donostia International Physics Center | Errea I.,Ikerbasque | Calandra M.,French National Center for Scientific Research | Pickard C.J.,University College London | And 7 more authors.
Physical Review Letters | Year: 2015

We use first-principles calculations to study structural, vibrational, and superconducting properties of H2S at pressures P≥200GPa. The inclusion of zero-point energy leads to two different possible dissociations of H2S, namely 3H2S→2H3S+S and 5H2S→3H3S+HS2, where both H3S and HS2 are metallic. For H3S, we perform nonperturbative calculations of anharmonic effects within the self-consistent harmonic approximation and show that the harmonic approximation strongly overestimates the electron-phonon interaction (λ≈2.64 at 200 GPa) and Tc. Anharmonicity hardens HS bond-stretching modes and softens HS bond-bending modes. As a result, the electron-phonon coupling is suppressed by 30% (λ≈1.84 at 200 GPa). Moreover, while at the harmonic level Tc decreases with increasing pressure, the inclusion of anharmonicity leads to a Tc that is almost independent of pressure. High-pressure hydrogen sulfide is a strongly anharmonic superconductor. © 2015 American Physical Society.

Li Y.,Jiangsu University | Li Y.,Jilin University | Wang Y.,Jilin University | Pickard C.J.,University College London | And 3 more authors.
Physical Review Letters | Year: 2015

Alkali metals exhibit unexpected structures and electronic behavior at high pressures. Compression of metallic sodium (Na) to 200 GPa leads to the stability of a wide-band-gap insulator with the double hexagonal hP4 structure. Post-hP4 structures remain unexplored, but they are important for addressing the question of the pressure at which Na reverts to a metal. Here, we report the reentrant metallicity of Na at the very high pressure of 15.5 terapascal (TPa), predicted using first-principles structure searching simulations. Na is therefore insulating over the large pressure range of 0.2-15.5 TPa. Unusually, Na adopts an oP8 structure at pressures of 117-125 GPa and the same oP8 structure at 1.75-15.5 TPa. The metallization of Na occurs on the formation of a stable and striking body-centered cubic cI24 electride structure consisting of Na12 icosahedra, each housing at its center about one electron that is not associated with any Na ions. © 2015 American Physical Society.

Xiao L.,Jilin University | Jin L.,Jilin University
Astrophysical Journal | Year: 2015

In Paper I, we suggested that the diversity of extrasolar planets might originate from the diversity of molecular cloud cores and specifically illustrated the relationship between semi-major axes of planets in a planetary system and the properties of its progenitor cloud core. In this paper, we investigate the dependence of the mass of a giant planet on the progenitor core properties. We give numerical results of planet masses as a function of the core properties by using the core accretion model of planet formation. Comparing with observations, our model could explain the range and the most frequent values of observed masses of gas giant planets. Our calculations could interpret the observed pileup of gas giants at >1 AU and the distinct deficit of gas giants from ∼0.05 to 1 AU. Our calculations indicate that it is difficult to form gas giant planets outside 20 AU and the intermediate mass planets might be found at ∼15-30 AU as the observing technique advances. We suggest a formation mechanism of super-Jupiters in the framework of the core accretion model of planet formation. A super-Jupiter can form under the condition that a disk is gravitationally unstable ( high viscosity ) when a protoplanet opens the deep gap. Our calculations infer that the upper limit of super-Jupiter masses, the range of semi-major axes, and the occurrence rate of super-Jupiters increase with the central star mass. We find that gas giant planets should commonly exist around various stellar masses. © 2015. The American Astronomical Society. All rights reserved.

Zhang M.,Jilin University | Zhang M.,Beihua University | Liu H.,Jilin University | Li Q.,Jilin University | And 5 more authors.
Physical Review Letters | Year: 2015

We solve the crystal structure of recently synthesized cubic BC3 using an unbiased swarm structure search, which identifies a highly symmetric BC3 phase in the cubic diamond structure (d-BC3) that contains a distinct B-B bonding network along the body diagonals of a large 64-atom unit cell. Simulated x-ray diffraction and Raman peaks of d-BC3 are in excellent agreement with experimental data. Calculated stress-strain relations of d-BC3 demonstrate its intrinsic superhard nature and reveal intriguing sequential bond-breaking modes that produce superior ductility and extended elasticity, which are unique among superhard solids. The present results establish the first boron carbide in the cubic diamond structure with remarkable properties, and these new findings also provide insights for exploring other covalent solids with complex bonding configurations. © 2015 American Physical Society.

Wu J.-H.,Jilin University | Horsley S.A.R.,University of Exeter | Artoni M.,European Laboratory for Nonlinear Spectroscopy | Artoni M.,CNR Institute of Acoustics and Sensors Orso Mario Corbino | La Rocca G.C.,Normal School of Pisa
Light: Science and Applications | Year: 2013

The typically tiny effect of radiation damping on a moving body can be amplified to a favorable extent by exploiting the sharp reflectivity slope at one edge of an optically induced stop-band in atoms loaded into an optical lattice. In this paper, this phenomenon is demonstrated for the periodically trapped and coherently driven cold 87Rb atoms, where radiation damping might be much larger than that anticipated in previous proposals and become comparable with radiation pressure. Such an enhancement could be observed even at speeds of only a few meters per second with less than 1.0% absorption, making radiation damping experimentally accessible. © 2013 CIOMP. All rights reserved.

Fan X.,Jilin University | Zheng W.T.,Jilin University | Kuo J.-L.,Academia Sinica, Taiwan | Singh D.J.,Oak Ridge National Laboratory | Singh D.J.,Jilin University
ACS Applied Materials and Interfaces | Year: 2013

We analyzed the adsorption of Li on graphene in the context of anodes for lithium-ion batteries (LIBs) using first-principles methods including van der Waals interactions. We found that although Li can reside on the surface of defect-free graphene under favorable conditions, the binding is much weaker than to graphite and the concentration on a graphene surface is not higher than in graphite. At low concentration, Li ions spread out on graphene because of Coulomb repulsion. With increased Li content, we found that small Li clusters can be formed on graphene. Although this result suggests that graphene nanosheets can conceivably have a higher ultimate Li capacity than graphite, it should be noted that such nanoclusters can potentially nucleate Li dendrites, leading to failure. The implications for nanostructured carbon anodes in batteries are discussed. © 2013 American Chemical Society.

Sun Y.-L.,Jilin University | Sun Y.-L.,Northwestern University | Yang Y.-W.,Jilin University | Yang Y.-W.,Northwestern University | And 5 more authors.
Small | Year: 2013

Mechanized silica nanoparticles, equipped with pillar[5]arene-[2] pseudorotaxane nanovalves, operate in biological media to trap cargos within their nanopores, but release them when the pH is lowered or a competitive binding agent is added. Although cargo size plays an important role in cargo loading, cargo charge-type does not appear to have any significant influence on the amount of cargo loading or its release. These findings open up the possibility of using pillar[n]arene and its derivatives for the formation of robust and dynamic nanosystems that are capable of performing useful functions. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The existence of fundamental differences between lung adenocarcinoma (AC) and squamous cell carcinoma (SCC) in their underlying mechanisms motivated us to postulate that specific genes might exist relevant to prognosis of each histology subtype. To test on this research hypothesis, we previously proposed a simple Cox-regression model based feature selection algorithm and identified successfully some subtype-specific prognostic genes when applying this method to real-world data. In this article, we continue our effort on identification of subtype-specific prognostic genes for AC and SCC, and propose a novel embedded feature selection method by extending Threshold Gradient Descent Regularization (TGDR) algorithm and minimizing on a corresponding negative partial likelihood function. Using real-world datasets and simulated ones, we show these two proposed methods have comparable performance whereas the new proposal is superior in terms of model parsimony. Our analysis provides some evidence on the existence of such subtype-specific prognostic genes, more investigation is warranted. © 2015 Suyan Tian.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Liu S.,Jilin University | Yu B.,Jilin University | Zhang H.,Jilin University | Fei T.,Jilin University | Zhang T.,Jilin University
Sensors and Actuators, B: Chemical | Year: 2014

NO2 gas sensor has been constructed using reduced graphene oxide-ZnO nanoparticles (ZnO-rGO) hybrids as sensing materials. Most importantly, the sensor exhibits higher sensitivity, shorter response time and recovery time than those of the sensor based on rGO, indicating that the sensing performances for NO2 sensing operating at room temperature have been enhanced by introduction of ZnO nanoparticles into rGO matrix. © 2014 Elsevier B.V.

Yu W.,Jilin University | Xu W.,Jilin University | Song H.,Jilin University | Zhang S.,Jilin University
Dalton Transactions | Year: 2014

Oleic acid-capped NaYF4:Yb3+/Er3+ upconversion nanocrystals (UCNCs) with different sizes and crystalline phases were prepared, and their temperature-dependent upconversion luminescence (UCL) and dynamics were studied. It is interesting to observe that the temperature-dependent behavior of UCL for the β-phase (25 nm, 45 nm and bulk) and α-phase (<10 nm) UCNCs is quite different. The UCL intensity of Er3+ ions of the β-phase NaYF4 demonstrates a maximum around 100 K, while the intensity of the α-phase quenches monotonously with elevated temperature (10-400 K). The intensity ratio of 2H11/2-4I15/2 to 4S 3/2-4I15/2, RHS, increases solely with temperature for β-phase NaYF4, while for the α-phase sample, it demonstrates a complex and indeterminate variation as a function of temperature. In the β-phase samples, rising processes were observed in the dynamics of Er3+ ions, while in the α-phase sample, no rising process was observed and the decay processes of Er3+ ions were bi-exponential. The rationale for these different temperature-dependent UCL properties was explained carefully. This journal is © the Partner Organisations 2014.

Ma G.,Jilin University
Pure and Applied Geophysics | Year: 2013

We present two new potential-inversion methods for estimating the depth and the nature (structural index) of the source, which use various combinations of different forms of local wavenumbers and the information about the horizontal location to estimate individually the depth and the nature of a magnetic source. The improved local wavenumber methods only use the horizontal offset and vertical offset of local wavenumbers to estimate the depth and the structural index of the source, so they yield more stable results compared with the results obtained by current methods that require the derivatives of local wavenumbers. Tests conducted with synthetic noise-free and noise-corrupted magnetic data show that the proposed methods can successfully estimate the depth and the nature of the geologic body. However, our methods are sensitive to high-wavenumber noise present in the data, and we reduced the noise effect by upward continuing the noise-corrupted magnetic data. The practical application of the new methods is tested on a real magnetic anomaly over a dike whose source parameters are known and the inversion results are consistent with the true values. © 2012 Springer Basel AG.

Lin Q.,Jilin University
Applied Mechanics and Materials | Year: 2014

In this paper, a novel method which can identify error parameters of accelerometer accurately in the absence of high precision test turntable occasions is provided. The novel method makes use of artificial fish swarm algorithm(AFSA), permits to obtain an accurate identification by taking the acceleration norm as observation, and the standard variance of norm error as optimization index. The identification test is carried out on the platform of fiber optic gyro (FOG) strapdown inertial navigation system (SINS), and the 24-hours static navigation test is also executed. The validity of our method is verified by experiment results, which shows significant profit in practice. © (2014) Trans Tech Publications, Switzerland.

Zhang X.E.,Jilin University
Zhonghua shi yan he lin chuang bing du xue za zhi = Zhonghua shiyan he linchuang bingduxue zazhi = Chinese journal of experimental and clinical virology | Year: 2012

To study the pathogen and characteristics of viral diarrhea in children in Changchun area. 460 stools specimens were collected from children with acute diarrhea cured in the childrens, hospital of Changchun in 2010. Rotavirus were detected by ELISA, caliceverus and astrovirus were detected by reverse transcription-polymerase chain reactions (RT-PCR), adenovirus were detected by polymerase chain reactions (PCR). A total of 460 specimens were detected. The detection rate of rotavirus, caliceverus, astrovious, adenovious respectively is 35.22%, 20.43%, 9.78%, 3.70%, the detectablerate of mixed infection is 7.61%, children under 2 years old were the major patient. The main genotypes of the virus: rotavirus (G3P[8]), caliceverus (GII-4), astrovious (type I), adenovious (Ad41). Rotavirus is the main pathogen in Changchun. Followed by caliceverus, astrovious, adenovious.

Zhang H.,Shanghai Maritime University | Zhang H.,Ohio State University | Zhang X.,Jilin University | Wang J.,Ohio State University
Vehicle System Dynamics | Year: 2014

In this paper, we investigate the vehicle lateral dynamics stabilisation problem to enhance vehicle handling by considering time-varying longitudinal velocity. The longitudinal velocity is described by a polytope with finite vertices and a novel technique is proposed to reduce the number of vertices. Since the tyre dynamics is nonlinear, the cornering stiffness is represented via the norm-bounded uncertainty. Concerning the time-varying velocity and the nonlinear tyre model, a linear parameter-varying vehicle model is obtained. As the velocity and the states are measurable, a gain-scheduling state-feedback controller is introduced. In the lateral control, the sideslip angle is required to be as small as possible and the yaw rate is constrained to a certain level. Thus, the control objective is to minimise the sideslip angle while the yaw rate is under a prescribed level or constrain both the sideslip angle and the yaw rate to prescribed levels. To consider the transient response of the closed-loop system, the D-stability is also employed in the energy-to-peak control. The optimal controller can be obtained by solving a set of linear matrix inequalities. A nonlinear vehicle model is utilised to illustrate the design procedure and the effectiveness of the proposed design method. Finally, simulations and comparisons are carried out to show the significant advantage of the designed controller. Compared to the open-loop system, the closed-loop system with the designed controller can achieve much smaller sideslip angle and the yaw rate is closer to the desired yaw rate from a reference model. Therefore, the vehicle safety and the handling are both improved in our simulation cases. © 2014 © 2014 Taylor & Francis.

Liu Y.,Jilin University | Wu Z.,Jilin University | Zhang H.,Jilin University
Advances in Colloid and Interface Science | Year: 2014

Two-dimensional (2D) nanomaterials with the thickness at atomic level are promising candidates for a wide range of applications, and now reach the point to create diversified 2D architectures. The colloidal synthesis route is powerful to produce crystalline nanosheets, nanoribbons and nanoplatelets, and the self-assembly strategy is robust to integrate the functionalities of different nano-objects. In this review, we bridge the colloidal synthesis of nanosheets and the 2D self-assembly of nanoclusters (NCs) with the aim to further optimize the physical and chemical properties of 2D nanomaterials. Ultrasmall NCs, the intermediate for synthesizing nanosheets, are highlighted to show the similarity of 2D crystallization and 2D self-assembly. The modification of conventional 2D colloidal synthesis route greatly permits the controlled self-assembly of NCs into free-standing monolayers in colloidal solutions. © 2013 Elsevier B.V.

Xu M.-L.,Jilin University | Liu J.-B.,Jilin University | Lu J.,Jilin University
Applied Spectroscopy Reviews | Year: 2014

We present a review concerning the determination and control of pesticide residues and transformation products in beverages. We review preparation methods using microextraction techniques, which are time-consuming, inexpensive, simple, and endeavor to be environment friendly. Mass spectrometry (MS) and tandem mass spectrometry (MS/MS) technologies are able to detect and quantify matrix-induced chromatographic response effects (matrix effects) accurately, even with the low milligram per kilogram levels. Rapid detection technology is an important tool in food product analysis. We review the technology to analyze the persistence of pesticide residues in beverages in order to effectively control their quality and safety. © 2014 Taylor and Francis Group, LLC.

Jiang J.,Jilin University
World journal of gastroenterology : WJG | Year: 2012

To investigate the role of expressions of Ki-67, p53, epidermal growth factor receptor (EGFR) and cyclooxygenase-2 (COX-2) in gastrointestinal stromal tumor (GIST) grading and prognosis. Tumor tissue was collected retrospectively from 96 patients with GIST. Antibodies against Ki-67, p53, EGFR and COX-2 were used for immunohistochemical staining. Tumor grading was designated according to a consensus system and the staining was quantified in 3 categories for each antibody in the statistical analysis. The Ki-67 expression in GISTs was significantly associated with the size of the tumors, mitotic rate and the risk of malignancy (χ(2) = 15.51, P = 0.02; χ(2) = 22.27, P < 0.001; χ(2) = 20.05; P < 0.001). The p53 expression was also significantly correlated with mitotic rate and the risk of malignancy (χ(2) = 9.92, P = 0.04; χ(2) = 9.97; P = 0.04). Over-expression of Ki-67 was strongly correlated with poor survival (χ(2) = 10.44, P = 0.006), but no correlation was found between the expression of p53, EGFR or COX-2 and survival. Multivariate analysis further demonstrated that Ki-67 expression (relative risk = 15.78, 95% CI: 4.25-59.37) could be used as an independent prognostic value for GIST patients. Adjuvant imatinib therapy could improve clinical outcomes in the patients with high risk and intermediate risk of recurrence after complete tumor resections (median survival time: 52 mo vs 37 mo, χ(2) = 7.618, P = 0.006). Our results indicated that the expression of Ki-67 could be used as an independent prognostic factor for GIST patients.

Han X.-G.,Jilin University | Zhang C.-X.,Jilin University
Journal of Chemical Physics | Year: 2010

The phase behavior of physically associating polymer solutions, where the polymer chain contains a small fraction of "stickers" regularly placed along the backbone, is studied using self-consistent field lattice model. Two inhomogenous morphologies are observed. One is a microfluctuation homogenous (MFH) morphology, where the mean-field values of the local average concentrations of polymers φP (r) and stickers φst (r) slightly fluctuate around their respective bulk average values φ- P and φ- st and regularly from site to site. The other is a randomly close-packed micelle (RCPM) morphology. The structure of the micelle in RCPM morphology is similar to that of the "flower micelle" in the telechelic associative polymer system, where stickers are located in the core of the micelle and nonsticky groups in the corona. When φ- P 0.08, if homogenous associating polymer solutions are cooled, MFH morphology appears, and the system entirely changes from homogenous solutions (HS) to MFH morphology; If the solutions are cooled further, RCPM morphology appears. When φ- P <0.08, however, RCPM morphology appears immediately. If φ- P <0.53, a macroscopic phase separation, where the polymer rich phase is RCPM morphology, occurs. If φ- P 0.53, only RCPM morphology is found in the system. A peak appears in the temperature-dependent specific-heat curve CV (Ξ) at each transition point. For the HS-MFH transition, CV (Ξ) has an abrupt increase and a slow decrease, whereas for the MFH-RCPM transition, both the increase and the decrease in CV (Ξ) are slow. Furthermore, the system with only MFH morphology may be trapped in one of the two energy basins in a experimental time scale. However, the appearance of RCPM morphology means that the system is trapped in one of a series of "deeper" energy basins, and it is very difficult to jump off this deep basin into the one of MFH morphology or one of the other RCPM morphologies through thermal fluctuations. © 2010 American Institute of Physics.

Pan X.-L.,Jilin University | Liu W.,Jilin University | Liu J.-Y.,Jilin University
Journal of Physical Chemistry B | Year: 2013

The enzyme α-galactosidase (α-GAL), a member of glycoside hydrolase family 27, catalyzes the removal of a nonreducing terminal α-galactose residue from polysaccharides, glycolipids, and glycopeptides. α-GAL is believed to have the double displacement retaining reaction mechanism. In this work, the glycosylation step catalyzed by human α-GAL was computationally simulated with quantum mechanics/molecular mechanics metadynamics. Our simulations show that the overall catalytic mechanism follows a DN*AN-like mechanism, and the transition state has a oxocarbenium ion like character with a partially formed double bond between the ring oxygen and C5′ carbon atoms. In addition, the galactosyl ring of the substrate follows a conformational itinerary of 4C1 → [E3/4H3]§ → 1S3 along the reaction coordinate. © 2012 American Chemical Society.

He B.-R.,Nagoya University | Ma Y.-L.,Jilin University | Harada M.,Nagoya University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

We study the effects of light scalar mesons on the Skyrmion properties by constructing and examining a mesonic model including pion, rho meson, and omega meson fields as well as two-quark and four-quark scalar meson fields. In our model, the physical scalar mesons are defined as mixing states of the two- and four-quark fields. We first omit the four-quark scalar meson field from the model and find that when there is no direct coupling between the two-quark scalar meson and the vector mesons, the soliton mass is smaller and the soliton size is larger for lighter scalar mesons; when direct coupling is switched on, as the coupling strength increases, the soliton becomes heavy, and the radius of the baryon number density becomes large as the repulsive force arising from the ω meson becomes strong. We then include the four-quark scalar meson field in the model and find that mixing between the two-quark and four-quark components of the scalar meson fields also affects the properties of the soliton. When the two-quark component of the lighter scalar meson is increased, the soliton mass decreases and the soliton size increases. © 2015 American Physical Society. © 2015 American Physical Society.

Li W.,Jilin University | Kim Y.,Jilin University | Li J.,Jilin University | Lee M.,Jilin University
Soft Matter | Year: 2014

The construction of supramolecular polymers has been intensively pursued because the nanostructures formed through weak non-covalent interactions can be triggered by external stimuli leading to smart materials and sensors. Self-assemblies of coordination polymers consisting of metal ions and organic ligands in aqueous solution also provide particular contributions in this area. The main motivation for developing those coordination polymers originates from the value-added combination between metal ions and ligands. This review highlights the recent progress of the dynamic self-assembly of coordination polymers that result from the sophisticated molecular design, towards fabricating stimuli-responsive systems and bio-related materials. Dynamic structural changes and switchable physical properties triggered by various stimuli are summarized. Finally, the outlook for aqueous nanostructures originated from the dynamic self-assembly of coordination polymers is also presented. This journal is © the Partner Organisations 2014.

Fan X.,Jilin University | Zheng W.,Jilin University | Singh D.J.,Jilin University | Singh D.J.,Oak Ridge National Laboratory
Light: Science and Applications | Year: 2014

Light scattering by small particles has a long and interesting history in physics. Nonetheless, it continues to surprise with new insights and applications. This includes new discoveries, such as novel plasmonic effects, as well as exciting theoretical and experimental developments such as optical trapping, anomalous light scattering, optical tweezers, nanospasers, and novel aspects and realizations of Fano resonances. These have led to important new applications, including several ones in the biomedical area and in sensing techniques at the single-molecule level. There are additionally many potential future applications in optical devices and solar energy technologies. Here we review the fundamental aspects of light scattering by small spherical particles, emphasizing the phenomenological treatments and new developments in this field.

Chen K.,CAS Institute of Microbiology | Huang Y.-H.,Jilin University | Chen J.-L.,CAS Institute of Microbiology | Chen J.-L.,Fujian Agriculture and forestry University
Acta Pharmacologica Sinica | Year: 2013

Cancer stem cells (CSCs) have been identified as rare cell populations in many cancers, including leukemia and solid tumors. Accumulating evidence has suggested that CSCs are capable of self-renewal and differentiation into various types of cancer cells. Aberrantregulation of gene expression and some signaling pathways has been observed in CSCs compared to other tumor cells. CSCs are thought tobe responsible for cancer initiation, progression, metastasis, recurrence and drug resistance. The CSC hypothesis has recently attracted much attention due to the potential for discovery and development of CSC-related therapies and the identification of key molecules involved in controlling the unique properties of CSC populations. Over the past several years, a tremendous amount of effort has been invested in the development of new drugs, such as nanomedicines, that can take advantage of the "Achilles' heel" of CSCs by targeting cell-surface molecular markers or various signaling pathways. Novel compounds and therapeutic strategies that selectively target CSCs have been identified, some of which have been evaluated in preclinical and clinical studies. In this article, we review new findings related to the investigation of the CSC hypothesis, and discuss the crucial pathways involved in regulating the development of CSC populations and the advances in studies of drug resistance. In addition, we review new CSC-targeted therapeutic strategies aiming to eradicate malignancies. © 2013 CPS and SIMM.

Zhang H.,Jilin University | Cheng X.,Jilin University | Wang K.,Jilin University | Huang S.,Jilin University | Wang Y.,Jilin University
Angewandte Chemie - International Edition | Year: 2015

A series of highly efficient deep red to near-infrared (NIR) emissive organic crystals 1-3 based on the structurally simple 2′-hydroxychalcone derivatives were synthesized through a simple one-step condensation reaction. Crystal 1 displays the highest quantum yield (Φf) of 0.32 among the reported organic single crystals with an emission maximum (λem) over 710nm. Comparison between the bright emissive crystals 1-3 and the nearly nonluminous compounds 4-7 clearly gives evidence that a subtle structure modification can arouse great property changes, which is instructive in designing new high-efficiency organic luminescent materials. Notably, crystals 1-3 exhibit amplified spontaneous emissions (ASE) with extremely low thresholds. Thus, organic deep red to NIR emissive crystals with very high Φf have been obtained and are found to display the first example of NIR fluorescent crystal ASE. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Zhao Y.,Jilin University | Hu Z.,Jilin University
Chemical Communications | Year: 2012

How structural features observed computationally are connected to excitation-wavelength dependent kinetics observed experimentally remains an unanswered question in the field of ionic liquids. Using molecular dynamics simulation methods and approximated models that simplify the electrostatic interactions in ionic liquids, we discovered that on the timescale shorter than the relaxation time of the photochemical process, the energetic heterogeneity in terms of distribution of excitation energies is the consequence of the structure heterogeneity formed by local arrangement of ions around the solute probe. © 2012 The Royal Society of Chemistry.

Zhang J.,Jilin University | Yan G.,Jilin University
Chaos | Year: 2010

A lattice Boltzmann model is developed for the one- and two-dimensional Burgers-Fisher equation based on the method of the higher-order moment of equilibrium distribution functions and a series of partial differential equations in different time scales. In order to obtain the two-dimensional Burgers-Fisher equation, vector σj has been used. And in order to overcome the drawbacks of "error rebound," a new assumption of additional distribution is presented, where two additional terms, in first order and second order separately, are used. Comparisons with the results obtained by other methods reveal that the numerical solutions obtained by the proposed method converge to exact solutions. The model under new assumption gives better results than that with second order assumption. © 2010 American Institute of Physics.

Zhang J.,Jilin University | Yan G.,Jilin University
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2010

A lattice Boltzmann model with complex distribution function for the complex Ginzburg-Landau equation (CGLE) is proposed. By using multiscale technique and the Chapman-Enskog expansion on complex variables, we obtain a series of complex partial differential equations. Then, complex equilibrium distribution function and its complex moments are obtained. Based on this model, the rotation and oscillation properties of stable spiral waves and the breaking-up behavior of unstable spiral waves in CGLE are investigated in detail. © 2010 The American Physical Society.

Suenaga D.,Nagoya University | He B.-R.,Nagoya University | Ma Y.-L.,Jilin University | Harada M.,Nagoya University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

We explore the mass splitting of heavy-light mesons with chiral partner structure in nuclear matter. In our calculation, we employed the heavy hadron chiral perturbation theory with chiral partner structure, and the nuclear matter is constructed by putting Skyrmions from the standard Skyrme model onto the face-centered cubic crystal and regarding the Skyrmion matter as nuclear matter. We find that, although the masses of heavy-light mesons with chiral partner structure are split in matter-free space and the Skyrmion phase, they are degenerated in the half-Skyrmion phase in which the chiral symmetry is restored globally. This observation suggests that the magnitude of the mass splitting of heavy-light mesons with chiral partner structure can be used as a probe of the phase structure of nuclear matter. © 2015 American Physical Society.

Cheng X.,Jilin University | Zhang H.,Jilin University | Ye K.,Jilin University | Wang Y.,Jilin University
Journal of Materials Chemistry C | Year: 2013

Here we report a bis(2′-hydroxychalcone)beryllium complex Be(HC) 2 that displays yellow fluorescence (λem = 557 nm; Φf = 0.10) in solution. Notably, the solution of this complex produces a non-emissive amorphous thin film (ACQ effect; fluorescent "OFF" state) but brightly emissive crystalline powders (AEE-active; fluorescent "ON" state) with deep red (λem = 678 nm; Φf = 0.27) or near infrared (λem = 700 nm; Φf = 0.20) emission colors and the fluorescent "ON" and "OFF" states can be smoothly transformed into each other by simple engineering processes: mechanical grinding and solvent fuming. © 2013 'The Royal Society of Chemistry.

Zheng K.,Jilin University | Liu Z.,Jilin University | Lv C.,Jilin University | Qin W.,Jilin University
Journal of Materials Chemistry C | Year: 2013

Optical temperature sensing characteristics based on the ultraviolet (UV) upconversion luminescence (UCL) of Gd3+ ions are reported here for the first time. Under 980 nm excitation, the temperature dependence five-photon UV UCL from the 6PJ and 6IJ levels of Gd3+ ions in NaLuF4:Yb3+, Tm3+, Gd3+ microcrystals were investigated systematically. The fluorescence intensity ratios (FIR) of two pairs of thermally coupled levels ( 6P5/2, 6P7/2 and 6I 9/2, 6I7/2) were studied as a function of temperature in a range of 298-523 K. The maximum sensor sensitivities were found to be about 0.0004 K-1 (333 K) and 0.0029 K-1 (298 K) by exploiting the UC emissions from the 6PJ and 6IJ levels, respectively. This suggests that the Gd 3+-based UCL materials are promising prototypes for application as multi-mode probes for use in bio-separation, MRI imaging, optical thermometers, etc. This journal is © The Royal Society of Chemistry 2013.

Sun H.,Northeast Normal University | Zhang F.,Northeast Normal University | Wei H.,Jilin University | Yang B.,Jilin University
Journal of Materials Chemistry B | Year: 2013

Recently, researchers have paid much attention to the toxicity of QDs because of their rapidly increasing application in biomedicine. Recent investigations have indicated that QDs have influences on biological systems at the cellular, subcellular, and protein levels during the processes of imaging and therapeutic applications. The toxicity of QDs is related to their composition, surface functionality, size, shape, and charge, etc. among which composition and surface modification are two important elements. This feature article mainly concentrates on the latest developments in reducing QD toxicity by manipulating their composition and surface modification. Besides the cadmium-based QDs, the assessment of toxicity in vitro and in vivo for other QDs such as carbon dots, graphene QDs, silicon QDs, Ag2Se QDs, CuInS2@ZnS, InP QDs, hybrid QDs of carbon and CdSe@ZnS, etc., is generalized. Each kind of QD has its own advantages. Cadmium-based QDs have broad UV excitation, narrow emission and bright photoluminescence (PL), while cadmium-free ones present low toxicity. In fact, a lot of investigations show that the toxicity of QDs is dose dependent, whatever the composition. Consequently, surface modification becomes very important to reduce toxicity and simultaneously impart biocompatibility, stability, and specificity to QDs. Therefore, the functionalization of QDs with inorganic shells (e.g., CdSe@ZnS, CdSe@SiO2), polymers, bio- or natural macromolecules is summarized. Future research work should concentrate on preparing novel QDs with appropriate surface modification and investigating the long-term influence of QDs on absorption, distribution, metabolism, and elimination in vivo, especially for cadmium-free QDs such as carbon-based QDs, Ag2Se QDs, CuInS 2@ZnS QDs and InP QDs, etc. © 2013 The Royal Society of Chemistry.

Li Y.,Jilin University | Wang X.,Jilin University | Sun J.,Jilin University
Chemical Society Reviews | Year: 2012

In the past two decades, layer-by-layer (LbL) assembly has been proven to be a convenient and versatile method to fabricate functional films. However, using traditional dipping LbL assembly to fabricate micrometer-thick films is time consuming. Compared with ultrathin films, micrometer-thick films prepared by LbL assembly possess enhanced mechanical stability, and allow deposition of a significantly increased amount of materials and the integration of multiple functions. These merits of thick films produced by LbL assembly can result in new functions and allow the functions of ultrathin films fabricated by LbL assembly to be optimized. In this tutorial review, the methods for rapid fabrication of thick polymeric films involving LbL assembly are reviewed. The functions of such films that are relevant to their micrometer thickness are discussed. This journal is © The Royal Society of Chemistry 2012.

Zhang H.,Jilin University | Liu Y.,Jilin University | Yao D.,Jilin University | Yang B.,Jilin University
Chemical Society Reviews | Year: 2012

Inorganic nanoparticles (NPs) with diversified functionalities are promising candidates in future optoelectronic and biomedical applications, which greatly depend on the capability to arrange NPs into higher-order architectures in a controllable way. This issue is considered to be solved by means of self-assembly. NPs can participate in self-assembly in different manners, such as smart self-organization with blended molecules, as the carriers of host molecules for assembly and disassembly with guest molecules, as netpoints to endow the architectures specific functionalities, and so forth. To enhance the structural stability of the as-prepared assembly architectures, polymers have been utilized to create NP-polymer composites. Meanwhile, such a strategy also demonstrates the possibility of integrating the functionalities of NPs and/or polymers by forming regular architectures. The emerging interest in the current optoelectronic and biological areas strongly demands intelligent nanocomposites, which are produced by combination of the excellent functionalities of NPs and the responsiveness of polymers. On the basis of the recent progress in fabricating NP-polymer composites, this critical review summarizes the development of new methods for fabricating regular self-assembly architectures, highlights the reversible assembly and disassembly behavior, and indicates the potential applications. This journal is © The Royal Society of Chemistry 2012.

Single-molecule force spectroscopy (SMFS) opens new avenues for elucidating the structures and functions of large coiled molecules such as synthetic and biopolymers at the single-molecule level. In addition, some of the features in the force-extension curves (i.e. force spectra) are closely related to primary/secondary structures of the molecules being stretched. For example, the long force plateau in the DNA stretching curve is related to the double-helix structure. These features can be regarded as the force fingerprints of individual macromolecules. These force fingerprints can therefore be used as indicators/criteria of single-molecule manipulation during the measurement of some unknown intra- or intermolecular interactions. By comparing the force spectra of a single polymer chain before and after interaction with other molecules, the mode/strength of such molecular interactions can be derived. This Review focuses on recent advances in AFM-based SMFS studies on molecular interactions in both synthetic and biopolymer systems using a single macromolecular chain as probe, including interactions between nucleic acids and proteins, mechanochemistry of covalent bonds, conformation-regulated enzymatic reactions, adsorption and desorption of biopolymers on a flat surface or from the nanopore of a carbon nanotube, and polymer interactions in the condensed state. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sun J.,Jilin University | Sun J.,Ohio State University | Bhushan B.,Jilin University
RSC Advances | Year: 2012

Nacre (known as mother of pearl) is the iridescent inner shell layer of some mollusks. Nacre is composed of 95 wt% aragonite (a crystallographic form of CaCO 3) and 5 wt% organic materials (proteins and polysaccharides). It is well known that it exhibits high fracture toughness, much greater than that of monolithic aragonite, because of its ingenious structure. It also exhibits energy absorption properties. It has a complex hierarchical microarchitecture that spans multiple length scales from the nanoscale to the macroscale. It includes columnar architectures and sheet tiles, mineral bridges, polygonal nanograins, nanoasperities, plastic microbuckling, crack deflection, and interlocking bricks, which exhibit a remarkable combination of stiffness, low weight and strength. Nacre's special self-assembly characteristics have attracted interest from materials scientists for the development of laminated composite materials, molecular scale self-assembly and biomineralization. This paper reviews the characteristics of hierarchical structure and the mechanical properties of nacre that provide the desired properties, and the latest developments and biomimetic applications. This journal is © 2012 The Royal Society of Chemistry.

Liang Q.,Jilin University
Journal of Nanoparticle Research | Year: 2016

In this work, we show that compositionally controlled Cu2(Sn1–xGex)S3 nanocrystals can be successfully synthesized by the hot-injection method through careful tuning the Ge/(Sn+Ge) precursor ratio. The band gaps of the resultant nanocrystals are demonstrated to be linearly tuned from 1.45 to 2.33 eV by adjusting the composition parameter x of the Ge/(Sn+Ge) ratio from 0.0 to 1.0. The crystalline structures of the resultant NCs have been studied by the X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), select area electron diffraction (SAED), and Raman spectroscopy. A ligand exchange procedure is further performed to replace the native ligands on the surface of the NCs with sulfur ions. The photoresponsive behavior indicates the potential use of as-prepared Cu2(Sn1–xGex)S3 nanocrystals in solar energy conversion systems. The synthesis of compositionally controlled Cu2(Sn1–xGex)S3 nanocrystals reported herein provides a way for probing the effect of Ge inclusion in the Cu-Sn-S system thin films. © 2016, The Author(s).

Wang C.,Jilin University | Xiao B.,Jilin University | Ding Y.-H.,Jilin University
ChemPhysChem | Year: 2012

Many outstanding properties of graphene are blocked by the existence of structural defects. Herein, we propose an important healing mechanism for the growth of graphene, which is produced via plasma-enhanced chemical vapor decomposition (PECVD), that is, the healing of graphene with single vacancies by decomposed CH 4 (hydrocarbon radical CH x, x=1, 2, 3). The healing processes undergo three evolutionary steps: 1) the chemisorption of the hydrocarbon radicals, 2) the incorporation of the C atom of the hydrocarbon radicals into the defective graphene, accompanied by the adsorption of the leaving H atom on the graphene surface, 3) the removal of the adsorbed H atom and H 2 molecule to generate the perfect graphene. The overall healing processes are barrierless, with a huge released heat of 530.79, 290.67, and 159.04 kcal mol -1, respectively, indicative of the easy healing of graphene with single vacancies by hydrocarbon radicals. Therefore, the good performance of the PECVD method for the generation of graphene might be ascribed to the dual role of the CH x (x=1, 2, 3) species, acting both as carbon source and as defect healer. Growing well: Many outstanding properties of graphene are blocked by the existence of structural defects (see picture). An important healing mechanism that takes place during the growth of this material via plasma-enhanced chemical vapor decomposition (PECVD) is proposed. The three-step process is based on the incorporation of C atoms from hydrocarbon radicals into the single-vacancy defects of graphene. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Qian Z.-H.,Jilin University | Wang Y.-J.,Jilin University
Tien Tzu Hsueh Pao/Acta Electronica Sinica | Year: 2012

Based on analyzing IoT two basic concepts, architecture of IoT is proposed, which includes underlayer network distribution, convergence gateway access, inter-connected network integration and terminal user application. In the architecture, a protocol structure of IoT is given, which consists of network protocol layers, network control platform and application terminal platform, and the key technologies for IoT have been discussed concerning hardware and software. Six development conceptions of future IoT have been presented based on summarizing the existing problems of IoT in standards, technologies, security and application.

Yin X.,Jilin University | Meng F.,Jilin University | Wang L.,Jilin University
Journal of Materials Chemistry C | Year: 2013

A class of new compounds consisting of a tetraphenylethene (TPE) core and hydrophilic peripheral oligo(ethylene glycol) chains was synthesized. These newly synthesized compounds showed aggregation-induced emission (AIE) nature which originated from the TPE core, and their peripheral oligo(ethylene glycol) chains impart water-solubility for the whole molecules. These compounds exhibit a lower critical solution temperature behavior in water. The phase transition temperature of TPE derivatives increases with the increase in the length of oligo(ethylene glycol) chains. By taking advantage of the AIE properties and thermosensitivity, these compounds are able to sense temperature by showing different emission intensities. When being heated above its phase-transition temperature, these compounds start to aggregate, which results in the restricted intramolecular rotation of the TPE moiety. Consequently, the aqueous solutions of these compounds show a stronger fluorescence. The temperature-induced fluorescence change is highly reversible. © 2013 The Royal Society of Chemistry.

Shi Z.,Jilin University | Zhao X.,Jilin University | Huang X.,Jilin University
Journal of Materials Chemistry C | Year: 2013

Based on first-principles computations, the geometries, stabilities, electronic and magnetic properties of fully and partially hydrogenated boron nitride nanoribbons (BNNRs) were investigated. Our results from the theoretical computation revealed that the boat and stirrup configurations were the most stable ones among the boat, chair and stirrup configurations for zigzag and armchair fully hydrogenated BNNRs, respectively. The fully hydrogenated 10-zBNNRs exhibited energetically degenerated ferromagnetic (FM) and ferrimagnetic (MFM) states for the boat and chair configurations. In the FM state, they showed metallic behavior, whereas in the MFM state, only the energy levels in the spin-down channel cross the Fermi-level, indicating the corresponding half-metallic feature. Moreover, intrinsic MFM half-metallic behavior can be observed in stirrup fully hydrogenated 10-zBNNRs. However, all of the fully hydrogenated 15-aBNNRs were nonmagnetic wide-band-gap semiconductors. By hydrogenating the zigzag BNNRs (zBNNRs) from the edge(s) step by step in a boat manner, we provide an effective approach to enrich the electronic and magnetic properties of zBNNRs and the transition of NM wide-gap semiconductor → NM narrow-gap semiconductor → energetically degenerated FM/MFM(AFM) metal/half-metal → FM metal → MFM half-metal can be achieved by controlling the hydrogenation patterns and ratios. These appealing features, especially the diverse electronic and magnetic transitions, in the unitary BNNR-based nanostructures may provide tremendous potential applications for integrated multi-functional and spintronic nanodevices. © 2013 The Royal Society of Chemistry.

Zhao Y.,Jilin University | Hu Z.,Jilin University
Journal of Physical Chemistry B | Year: 2013

Over the past decade, there has been much controversy regarding the microscopic mechanism by which the π-electron-rich carbon nanomaterials such as graphene and carbon nanotubes can be dispersed in ionic liquids. Through a combination of a quantum mechanical calculation on the level of density functional theory, an extensive molecular dynamics study on the time scale of microseconds, and a kinetic analysis at the experimental time scale, we have demonstrated that collective van der Waals forces between ionic liquids and graphene are able to describe both the short-ranged cation-π interaction and the long-ranged dispersion interaction and this microscopic interaction drives two graphene plates trapped in their metastable state while two graphene plates easily self-assemble into graphite in water. © 2013 American Chemical Society.

Zhao Y.Y.,Jilin University
Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology | Year: 2013

To construct a short hairpin (sh)RNA targeting the gene encoding the MDM2 oncoprotein in order to investigate its role in human hepatocellular carcinoma (HCC) and its potential for use as a gene therapy strategy to inhibit HCC growth in vivo. Small interfering (si)RNAs were designed targeting the MDM2 gene (siMDM2-1 and siMDM2-2) and unrelated sequences (negative control) and cloned into the expression plasmid pGCSilencer-U6-neo-GFP. A HCC mouse model was established by subcutaneous inoculation of HepG2 cells (2 x 10(6) in 0.2 ml) into 20 nude mice. The inoculated mice were divided into four equal groups for tumor-localized injections of saline, negative control siRNA plasmid, siMDM2-1 plasmid, and siMDM2-2 plasmid. Tumor growth was observed daily (by caliper measurement) for one month, when mice were sacrificed by cervical dislocation. The tumor mass was resected for analysis of tumor inhibition rate (% = [(average tumor weight of control group - average tumor weight of treatment group) / average tumor weight of control group x 100]) and effects on MDM2 and p53 mRNA and protein expression (by reverse transcription- PCR and western blotting, both normalized to beta-actin). Significance of between-group differences was assessed by one-way ANOVA or LSD test; pairwise comparisons were made by the Chi-squared test. siMDM2-1 and siMDM2-2 suppressed the xenografted tumor growth remarkably (60.6% and 54.6% inhibition rates, respectively), significantly reduced the expression ofMDM2 gene (62.8% and 61.6%) and protein (60.7% and 59.5%), and significantly increased p53 gene (47.1% and 45.6%) and protein (45.9% and 44.3%) (all, P < 0.05). shRNA-mediated silencing of the MDM2 gene effectively inhibits HCC tumorigenesis of subcutaneously xenografted HepG2 cells in nude mice, and the mechanism may involve p53.

Wang Z.,Jilin University | Yu J.,Jilin University | Xu R.,Jilin University
Chemical Society Reviews | Year: 2012

Zeolites are an important class of materials which are widely used in industry as catalysts, adsorbents and ion-exchangers. Their superior properties are closely related to their unique porous framework structure, as well as composition and morphology. The ever-growing needs for zeolitic materials in applications inspire us to think of the rational synthesis of zeolites with desired structures and properties. However, rationalization of zeolitic materials remains one of the most challenging issues in the zeolite research field due to their unclear formation mechanism. Despite this, many efforts have been devoted to synthesize zeolites in a more rational way. In this tutorial review, first, we demonstrate how the geometrical characteristics of zeolite frameworks affect the catalytic performances of the resulting materials; then, we present recent advances in synthetic innovations to target materials, and we further highlight the developments in computer simulations toward ab initio design and synthesis; finally, the future perspective on the rational synthesis of zeolitic materials with desired functions and structures will be described. © 2012 The Royal Society of Chemistry.

Sui N.,Jilin University | Li M.,CAS National Astronomical Observatories
Monthly Notices of the Royal Astronomical Society | Year: 2016

The (pre-)transitional discs are the relatively late states during disc evolution whose inner regions are cleared. We calculate the evolution of the discs by adopting different forms of viscosity (i.e. α and β prescriptions). The effect of photoevaporation is included. We also run calculations without photoevaporation. We show that photoevaporation is necessary for the inner holes or gaps to exist and can naturally explain the inside-out clearing of the discs. Both the inner holes and gaps are obtained for each prescription if we adopt appropriate parameters. If a gap forms, then there will be a hole in the disc. The locations of the gaps do not change much in both cases. The width of the gap is wider for the β-model. In both cases, the gaps or holes form at the late stage of disc evolution. When the viscosity is large enough, the inner region drains rapidly because of the high viscosity, giving rise to a very short gapped phase and long inner hole phase. The disc evolves faster for the β-model than for the β-model, which means, for a given disc lifetime, the initial mass of the disc should be larger for the β-model. From the existence of transitional discs, we show that the value of β is in the range of 10-5-10-6, which is consistent with previous studies. © 2016 The Authors.

Xue X.,Jilin University
Wei sheng wu xue bao = Acta microbiologica Sinica | Year: 2013

To sequence the complete genome of CVS-11 strain and establish a reverse genetic system of CVS-11 to further study its pathogenic mechanism, virulence genes and antigenic sites. We amplified12 fragments covering the complete genome of the CVS-11 strain by RT-PCR, and then cloned to pEASY-Blunt vector for sequencing the complete genome of CVS-11. We analyzed single restriction enzyme sites of the full length cDNA of the CVS-11 strain by DNAMAN and designed 4 pairs of specific primers. We amplified the full-length cDNA of CVS-11 by RT-PCR. We obtained four fragments and cloned into pcDNA3. 1. We named the full-length cDNA plasmid pcDNA3. 1-CVS-11. We also cloned helper plasmids pcDNA3.1-N, P, L and G expressing N, P, L and G protein of CVS-11 strain, respectively. We co-transfected NA cells with the full-length plasmid and four helper plasmids. We identified the supernatant of the transfected and then passaged NA cells by immunofluorescence staining and RT-PCR and found the recombinant virus rCVS-11 rescued successfully. Sequencing results showed that the complete genome of CVS-11 was composed of 11 927 nucleotides. The complete genome of CVS-11 encoded 5 structure proteins and gene array was the same as other reported rabies viruses. We successfully constructed a reverse genetic system of CVS-11, namely the full length plasmid pcDNA3. 1-CVS-11 and 4 help plasmids pcDNA3. 1-N, P, L, G and rescued the rCVS-11 from a full-length infectious cDNA clone. The reverse genetic system of the CVS-11 strain laid the foundation for future studies on rabies virus.

Xu H.,Jilin University | Yu B.,Beijing Institute of Technology
Expert Systems with Applications | Year: 2010

Email has become one of the fastest and most economical forms of communication. Email is also one of the most ubiquitous and pervasive applications used on a daily basis by millions of people worldwide. However, the increase in email users has resulted in a dramatic increase in spam emails during the past few years. This paper proposes a new spam filtering system using revised back propagation (RBP) neural network and automatic thesaurus construction. The conventional back propagation (BP) neural network has slow learning speed and is prone to trap into a local minimum, so it will lead to poor performance and efficiency. The authors present in this paper the RBP neural network to overcome the limitations of the conventional BP neural network. A well constructed thesaurus has been recognized as a valuable tool in the effective operation of text classification, it can also overcome the problems in keyword-based spam filters which ignore the relationship between words. The authors conduct the experiments on Ling-Spam corpus. Experimental results show that the proposed spam filtering system is able to achieve higher performance, especially for the combination of RBP neural network and automatic thesaurus construction. © 2009 Elsevier Ltd. All rights reserved.

Guli M.,University of Bristol | Guli M.,Jilin University | Lambert E.M.,University of Bristol | Li M.,University of Bristol | Mann S.,University of Bristol
Angewandte Chemie - International Edition | Year: 2010

(Figure Presented) Redox reactions were utilized to deposit periodically arranged Ag and Au nano-structures within the solvent channels of cross-linked lysozyme crystals (see picture for Ag-doped lysozyme crystals). The ability to crystallize lysozyme in various polymorphic forms provides an opportunity to tailor the architecture of the metalized nanostructures through judicious choice of the protein lattice. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA.

Sun J.,Jilin University | Sun J.,Ohio State University | Bhushan B.,Ohio State University
RSC Advances | Year: 2012

Insects of extremely small size have evolved to solve many problems. Their structure and mechanical properties information can be utilized to mimic them for industrial applications. Since beetle (Coleoptera, an order of insects) wings exhibit special functionalities, they have sparked worldwide research attention. Beetle wings are composed of a forewing (also known as elytron) and a hind wing. The elytra are rigid. A beetle's functional wings, which allow flying, are the hind wings. The elytra have an ingenious structure with superhydrophobic characteristics, a structural coloration and anti-adhesion characteristics. Their inner structure helps to provide light mass and high strength. The rotation angle and wing locking system of elytra are important features which increase beetles' ability to fly; they may furnish an insight for portable micro air vehicles (MAVs) and also provide inspiration for the design of bioinspired deployable systems. Studies of the structural and mechanical properties in biological systems may improve the understanding of natural solutions and advance the design of novel artificial materials. In this paper, the structure, mechanical properties and their relationship to function of beetle wings are discussed. Examples of bioinspired structures and materials are also presented. © 2012 The Royal Society of Chemistry.

Sun J.,CAS Changchun Institute of Applied Chemistry | Yue Y.,Jilin University | Wang P.,CAS Changchun Institute of Applied Chemistry | He H.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Journal of Materials Chemistry C | Year: 2013

We report a direct one-pot approach, employing tetrakis(hydroxymethyl) phosphonium chloride (THPC) and 11-mercaptoundecanoic acid (11-MUA) as combined reducing/capping agents, for the rapid preparation of fluorescent gold nanoclusters (AuNCs) from HAuCl4 in aqueous solution at room temperature. The as-prepared AuNCs exhibit a fluorescence emission at 535 nm, a quantum yield of 1.8% and average diameters of 2.0 ± 0.5 nm. The resultant MUA/THPC-AuNCs have been exploited, for the first time, for the highly sensitive and selective detection of silver ions (Ag+) in aqueous solution when using EDTA as a masking agent for Hg2+. The fluorescence intensity quenches linearly within the range of 25 nM to 3 μM with high sensitivity (LOD = 9 nM, S/N = 3) and this sensing system has been applied for environmental water sample analysis. This journal is © The Royal Society of Chemistry 2013.

Wang Y.,Jilin University | Wang W.,Yantai Wanhua Polyurethanes Co. | Song W.,Jilin University
Electrochimica Acta | Year: 2011

Cobalt oxide-doped copper oxide composite nanofibers (CCNFs) were successfully achieved via electrospinning followed by thermal treatment processes and then exploited as active electrode material for direct enzyme-free fructose detection. The morphology and the structure of as-prepared samples were investigated by X-ray diffraction spectrum (XRD) and scanning electron microscopy (SEM). The electrocatalytic activity of CCNFs films towards fructose oxidation and sensing performances were evaluated by conventional electrochemical techniques. Cyclic voltammetry (CV) and chronoamperometry (I-t) revealed the distinctly enhanced sensing properties towards fructose compared to pure copper oxide nanofibers (CNFs), i.e., showing significantly lowered overpotential of 0.30 V, ultrafast (1 s) and ultrasensitive (18.988 μA mM-1) current response in a wide linear range of 1.0 × 10 -5 M to 6.0 × 10-3 M with satisfied reproducibility and stability, which could be ascribed to the synergic catalytic effect of the binary CuO/Co3O4 composite nanofibers and the highly porous three-dimensional network films structure of the CCNFs. In addition, a good selectivity for fructose detection was achieved. Results in this work demonstrated that CCNFs is one of the promising catalytic electrode materials for enzymeless fructose sensor fabrication. © 2011 Elsevier Ltd. All Rights Reserved.

Yang H.,University of Colorado at Boulder | Liu Z.,Jilin University | Zhang W.,University of Colorado at Boulder
Advanced Synthesis and Catalysis | Year: 2013

A series of triphenolsilane-coordinated molybdenum(VI) propylidyne catalysts has been developed, which are resistant to small alkyne polymerization and compatible with various functional groups (including phenol substrates). The catalysts remain active in solution for days at room temperature (months at -30 °C). The catalysts are also compatible with 5 Å molecular sieves (small alkyne scavengers), and have enabled the homodimerization of small alkyne substrates at 40-70 °C in a closed system, with dimer products being obtained in 76-96% yields. A shape-persistent aryleneethynylene macrocycle (11) was also prepared on a gram scale with 0.5 mol% catalyst loading, in almost quantitative yield. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chen X.F.,Jilin University | Lian J.S.,Jilin University | Jiang Q.,Jilin University
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

First-principles calculations based on all-electron density functional theory are performed on hydrogenated graphene/boron nitride (BN) bilayer and graphene/BN multilayers to exploit the effects of the heterogeneous interface and external bias voltage on controlling their electronic properties. After hydrogenation, the emerging of the dipoles at the interface induced by the charge transfer between the graphene and the BN layer introduces a built-in potential difference, which plays a critical role in determining the band gaps of the resulting system. Tuning this internal potential difference through changing the number of BN layers or an external bias allows continuous modulation of the band gaps and leads to a linear transition from semiconductors to metals. © 2012 American Physical Society.

Liu M.,Qingdao University of Science and Technology | Zhang J.,Qingdao University of Science and Technology | Liu J.,Nanjing University of Science and Technology | Yu W.W.,Jilin University
Journal of Catalysis | Year: 2011

Stable poly(N-vinyl-2-pyrrolidone)-stabilized Pt/Ru colloidal nanoparticles (PVP-Pt/Ru) were prepared via ethanol reduction of H2PtCl 66H2O and RuCl3nH2O. The average diameters of the nanoparticles with different molar ratio of Pt/Ru were in a range of 2.1-2.8 nm with narrow size distributions. X-ray photoelectron spectroscopy verified that both Pt and Ru were in the metallic state and Ru was rich on the surface. These nanoparticles were employed to selectively hydrogenate ortho-chloronitrobenzene at 298 K and 0.1 MPa hydrogen pressure. They showed high activity [TOF was in the range of 0.8-5.3 × 10 -2 molo-CNB/(molM,surface atom) s] and high selectivity (93-99%) to ortho-chloroaniline (o-CAN) for the reaction, which were composition-dependent. The selectivity to o-CAN monotonously increased, but the activity of the catalyst decreased with the increasing proportion of Ru in Pt/Ru colloidal catalysts. PVP-1Pt/4Ru nanoparticles exhibited the highest selectivity of 99.0% to o-CAN at a complete conversion. © 2010 Elsevier Inc. All rights reserved.

Dong Y.,Jilin University | Junde H.,Jilin University
Nuclear Data Sheets | Year: 2014

The 2005 evaluation for A=54 (2006Hu08) has been updated. Detailed experimental nuclear structure data and decay data for all nuclei with mass chain A=54 are presented in this current evaluation. The new data and information are given in following datasets:. 54Ca: 9Be(76Ge, X) and Be(55Sc, p), (56Ti, 2p)54Sc: 54Ca β- decay and 54Sc IT decay54Ti: 54Sc β- decay54Cr: 54Mn ε decay, 56Fe(μ, nupng), and 238U(64Ni, Xγ)54Mn: 51V(20Ne, Xγ), 55Mn(p, pn), and 56Fe(μ, nu2ng)54Fe: 58Ni α decay, 9Be(55Co, Xγ), 54Fe(e, e'), 54Fe(p, p'), and Coulomb Excitation54Co: 54Ni ε decay, 55Cu εp decay, 28Si(32S, αpnγ), 54Fe(p,n), and 54Fe(3He, t)54Ni: 54Ni IT decay, 55Zn εp decay, 9Be(55Ni, Xγ), and 24Mg(32S, Xγ)54Zn: Ni(58Ni, X). © 2014.

The groundwater flow system is typical dissipative structure system, and its evolution can be described with system information entropies. The information entropies of groundwater in Shijiazhuang City had been calculated between 1960 and 2005, and the results show that the entropies have a decreasing trend throughout the research period, and they can be divided into our stages based on the groundwater flow system entropy variation as follows: entropy steady period (1960-1965), entropy decreasing period (1965-1980), entropy increasing period (1980-1995) and secondary entropy decreasing period (1995-2005); understanding the major and significant driving the pattern changing forces of groundwater levels is essential to groundwater management,. A new method of grey correlation analysis has been presented, and the results show that, the grey correlation grade between groundwater flow system information entropies and precipitation series is γ01 = 0.749, the grey correlation grade between groundwater flow system information entropies and groundwater withdrawal series is γ02 = 0.814, as the groundwater withdrawal is the main driving force of groundwater flow system entropy variation; based on the numerical simulation results, information entropy increased with artificial recharge, and a smaller recharge water volume would enhance the information entropy drastically, but then doubled water would not increase the information correspondingly, which could be useful to assess the health state of groundwater flow systems. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

Liu D.,Jilin University | Tong L.,Jilin University | Shi J.,Jilin University | Yang H.,Jilin University
Journal of Alloys and Compounds | Year: 2012

A series of core-shell bifunctional magnetic-optical YVO 4:Ln3+@Fe3O4 (Ln3+ = Eu3+ or Dy3+) nanocomposites have been successfully synthesized via two-step method. The nanocomposites have the advantage of high magnetic responsive and unique luminescence properties. The structure, luminescent and magnetic properties of the nanocomposites were investigated by XRD, TEM, PL and VSM. The maximum emission peaks of the nanocomposites are at 618 nm (doping Eu3+), 574 nm (doping Dy3+). The special saturation magnetization of the nanocomposites is 54 emu/g. The diameter of the nanocomposites is 400-900 nm. © 2011 Elsevier B.V.

Shao C.-B.,Jilin University | Ding Y.-H.,Jilin University
Physical Chemistry Chemical Physics | Year: 2010

Molecules with hypercoordinate planar centers have continued to receive enthusiastic attention due to their violation of the traditional models of three-dimensional chemical bonding and maximum tetracoordination. These electronic exotic but structurally aesthetic species have been optimistically conceived as building blocks in cluster-assembly for bulky materials. Recently, the planar hexacoordinate nitrogen (phN) unit, NB6 -, has been theoretically incorporated into a series of sandwich-like transition-metal compounds. However, the intrinsic stability of NB6 - in both gas-phase and assembly has not been tackled, though it is the key factor for predicting the viability of any molecules. In this paper, at the CCSD(T)/6-311+G(2df)//B3LYP/6-311+G(d)+ZPVE level, we investigate for the first time the thermodynamic and kinetic stability of the phN unit, NB 6 -, in both free and assembled ([NB6] 2Fe) forms. The calculated least barrier height of phN towards conversion is 9.2 and 4.4 kcal mol-1 in free and assembled forms, respectively. Most importantly, the phN structure is thermodynamically rather unstable, by 102.8 and 162.1 kcal mol-1 higher than the respective lower-lying conversion isomers. Therefore, in view of the combined thermodynamic and kinetic consideration, we propose that isolation of the phN structure of NB6 - in either gas phase or assembly is unlikely. The present results manifest that for predicting any viable molecule with exotic structures, investigation of its "intrinsic stability" is highly necessary. The maintenance of the phN-NB6 - is discussed at the 6-311+G(d)-B3LYP, MP2, CCSD and CCSD(T) optimization levels in comparison with the isoelectronic and milestone phC-CB6 2-. © 2010 the Owner Societies.

Ni J.-Y.,Sun Yat Sen University | Liu S.-S.,Jilin University | Xu L.-F.,Sun Yat Sen University | Sun H.-L.,Sun Yat Sen University | Chen Y.-T.,Sun Yat Sen University
World Journal of Gastroenterology | Year: 2013

AIM: To compare radiofrequency ablation (RFA) and transcatheter arterial chemoembolization (TACE) with RFA monotherapy in hepatocellular carcinoma (HCC). METHODS: We searched PubMed, Medline, Embase and Chinese databases (CBMdisc and Wanfang data) for randomized controlled trails comparing RFA plus TACE and RFA alone for treatment of HCC from January 2000 to December 2012. The overall survival rate, recurrence-free survival rate, tumor progression rate, and safety were analyzed and compared. The analysis was conducted on dichotomous outcomes and the standard meta-analytical techniques were used. Pooled odds ratios (ORs) with 95%CIs were calculated using either the fixed-effects or random-effects model. For each meta-analysis, the χ2 and I2 tests were first calculated to assess the heterogeneity of the included trials. For P < 0.05 and I2 > 50%, the assumption of homogeneity was deemed invalid, and the random-effects model was used; otherwise, data were assessed using the fixed-effects model. All statistical analysis was conducted using Review manager (version 4.2.2.) from the Cochrane collaboration. RESULTS: Eight randomized controlled trials were identified as eligible for inclusion in this analysis and included 598 patients with 306 treated with RFA plus TACE and 292 with RFA alone. Our data analysis indicated that RFA plus TACE was associated a significantly higher overall survival rate (OR1-year = 2.96, 95%CI: 1.84-7.74, P < 0.001; OR2-year = 3.72, 95%CI: 1.24-11.16, P = 0.02; OR3-year = 2.65, 95%CI: 1.81-3.86, P < 0.001) and recurrence-free survival rate (OR3-year = 3.00, 95%CI: 1.75-5.13, P < 0.001; OR5-year = 2.26, 95%CI: 1.43-3.57, P = 0.0004) vs that of RFA alone. The tumor progression rate in patients treated with RFA alone was higher than that of RFA plus TACE (OR = 0.60, 95%CI: 0.42-0.88, P = 0.008) and there was no significant difference on major complications between two different kinds of treatment (OR = 1.20, 95%CI: 0.31-4.62, P = 0.79). Additionally, the meta-analysis data of subgroups revealed that the survival rate was significantly higher in patients with intermediate- and large-size HCC underwent RFA plus TACE than in those underwent RFA monotherapy; however, there was no significant difference between RFA plus TACE and RFA on survival rate for small HCC. CONCLUSION: The combination of RFA with TACE has advantages in improving overall survival rate, and provides better prognosis for patients with intermediate-and large-size HCC. © 2013 Baishideng. All rights reserved.

ABSTRACT: Study Design. Meta-analysisObjective. The purpose of this study was to answer the following questions: (1) Does heterotopic ossification (HO) negatively influence clinical outcomes following cervical total disc replacement (CTDR)? (2) Should patients be classified into HO and non-HO groups? (3) Is there a more rational classification?Summary of Background Data. HO has emerged as a common complication following CTDR and has been an important reason for reoperation, thus limiting the use of the surgery. However, the influence of HO on clinical outcomes following CTDR has not been well established.Methods. A meta-analysis was conducted with studies identified by searches of MEDLINE, EMBASE, and the Cochrane Library. We calculated the weighted mean differences (WMD) of the visual analog scale (VAS) pain, neck disability index (NDI) and range of motion (ROM). Patients were classified into two groups under three classifications based on the grade of HO. Results were pooled using a fixed effect model or a random effects model, according to the heterogeneity.Results. There were significant differences in ROM uner all three classifications. The VAS pain and NDI between the patients with and without HO showed no significant difference following CTDR. Significant differences in VAS pain were observed when patients were classified into a “high-grade HO” group (McAfee grades 3 or 4 HO) and a “low-grade HO” group (McAfee grade 0, 1, or 2 HO).Conclusions. The presence of HO is not associated with clinical outcomes following CTDR. However, the severity of HO actually impacts clinical outcomes in an inverse manner which needs further investigation. Itʼs inappropriate to classify patients based on the presence of heterotopic ossification, further studies of the classifications (ROM-affecting HO vs. ROM-preserving HO; high-grade HO vs. low-grade HO) and cervical stability following CTDR are needed. © 2015 by Lippincott Williams & Wilkins

Fine N.M.,Mayo Medical School | Chen L.,Mayo Medical School | Chen L.,Jilin University | Bastiansen P.M.,Mayo Medical School | And 4 more authors.
Circulation: Cardiovascular Imaging | Year: 2013

Background-Although right ventricular (RV) dysfunction is a major determinant of outcome in patients with pulmonary hypertension (PH), the optimal measure of RV function is poorly defined. We hypothesized that RV strain measured by speckle-tracking echocardiography predicts outcome in PH over a broad range of pulmonary pressures. Methods and Results-Prospective peak RV longitudinal systolic strain measurement was performed on 575 patients (mean age, 56±18 years; 63% women) referred for echocardiography for known or suspected PH. Survival status was assessed over a median of 16.5 (interquartile range, 7.6-20.0) months. There were 406 patients with PH (71%) (74% group 1, 14% group 3, and 12% group 4) and 169 patients without evidence of PH (29%). Among patients with PH, 46% were World Health Organization functional class III-IV. The mean RV strain was -21.2±6.7% for all patients. RV strain declined with worse functional class, shorter 6-minute walk distances, higher N-terminal pro-B-type natriuretic peptide levels, and the presence of right heart failure. RV strain predicted outcome across pulmonary pressures and groups of PH. Eighteen-month survival was 92%, 88%, 85%, and 71% according to RV strain quartile (P<0.001), with a 1.46 higher risk of death (95% confidence interval, 1.05-2.12) per 6.7% decline in RV strain. RV strain predicted survival when adjusted for pulmonary pressure, pulmonary vascular resistance, and right atrial pressure and provided incremental prognostic value over conventional clinical and echocardiographic variables. Conclusions-Quantitative assessment of RV free-wall systolic strain is feasible and is a powerful predictor of the clinical outcome of patients with known or suspected PH. © 2013 American Heart Association, Inc.

Zhang G.,Jilin University | Zhao L.,Jilin University
Materials Letters | Year: 2012

Single-crystalline nickel nanopolyhedra with edge lengths about 60 nm were synthesized through a simple solvothermal method. Further adjusting the experimental parameters, two kinds of one-dimensional (1D) nickel submicron chains with quite different surfaces were also obtained. Here, the dosages of tetramethylammonium hydroxide and hydrazine hydrate play important roles in controlling the morphologies. The formation mechanism of nickel crystals with different shapes was deeply investigated. Moreover, it can be proved one more time by our experimental results that the morphologies of magnetic crystals have some influences on their magnetic properties. By magnetic measurement, the saturation magnetization of the nickel nanopolyhedra and submicron chains is respectively 48.2 and 57.3 emu/g. © 2012 Elsevier B.V. All rights reserved.

Jiang T.,Jilin University | Qin W.,Jilin University | Zhao D.,Jilin University
Materials Letters | Year: 2012

CaF 2:Yb,Tm nano- and micro-crystals with different sizes were synthesized by a simple hydrothermal method. All the nanocrystals present intense ultraviolet (UV), visible, and near infrared (NIR) upconversion (UC) luminescence. The relationship between the UC luminescence intensities and the sample sizes from 50 nm to 1200 nm was investigated. The UV UC luminescence intensity of the sample with the particle size around 600 nm was the highest among all the samples, but the NIR UC luminescence intensity of the sample was the lowest. Our experimental results indicated that there was a size between 50 nm and microscale at which the UV emission intensity was the highest for CaF 2 matrix. The size-dependent UC luminescence was proposed and analyzed based on experimental data. © 2012 Elsevier B.V. All rights reserved.

Li C.,Jilin University | Lian J.S.,Jilin University | Jiang Q.,Jilin University
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

The band structures, partial density of states, and electronic configuration of several AB2C full-Heusler compounds have been simulated using local-density approximation (LDA)+U. Results show that full-Heusler compounds with half-filled d orbitals and d5d5s2p6 electronic structures can also form topological insulators, which will double the range of topological insulator candidates. The band structures of full-Heusler compounds are affected by the covalent bondings of A-B and B-C jointly. The spin-up electrons and spin-down electrons influence the orbitals respectively, which leads to the magnetism of the materials, and all full-Heusler compounds with the magnetic moments ∼9μB are antiferromagnets, which may provide a new design of a tunable optical modulator. © 2011 American Physical Society.

Yang B.,Jilin University | Liu J.,Hong Kong Baptist University | Liu D.,Jilin University
IEEE Transactions on Systems, Man, and Cybernetics, Part B: Cybernetics | Year: 2012

Complex network theory provides a means for modeling and analyzing complex systems that consist of multiple and interdependent components. Among the studies on complex networks, structural analysis is of fundamental importance as it presents a natural route to understanding the dynamics, as well as to synthesizing or optimizing the functions, of networks. A wide spectrum of structural patterns of networks has been reported in the past decade, such as communities, multipartites, bipartite, hubs, authorities, outliers, and bow ties, among others. In this paper, we are interested in tackling the challenging task of characterizing and extracting multiplex patterns (multiple patterns as mentioned previously coexisting in the same networks in a complicated manner), which so far has not been explicitly and adequately addressed in the literature. Our work shows that such multiplex patterns can be well characterized as well as effectively extracted by means of a granular stochastic blockmodel, together with a set of related algorithms proposed here based on some machine learning and statistical inference ideas. These models and algorithms enable us to further explore complex networks from a novel perspective. © 2006 IEEE.

Gao J.,Jilin University | Gao J.,University of Minnesota | Truhlar D.G.,University of Minnesota | Wang Y.,University of Minnesota | And 4 more authors.
Accounts of Chemical Research | Year: 2014

ConspectusMolecular mechanical force fields have been successfully used to model condensed-phase and biological systems for a half century. By means of careful parametrization, such classical force fields can be used to provide useful interpretations of experimental findings and predictions of certain properties. Yet, there is a need to further improve computational accuracy for the quantitative prediction of biomolecular interactions and to model properties that depend on the wave functions and not just the energy terms. A new strategy called explicit polarization (X-Pol) has been developed to construct the potential energy surface and wave functions for macromolecular and liquid-phase simulations on the basis of quantum mechanics rather than only using quantum mechanical results to fit analytic force fields. In this spirit, this approach is called a quantum mechanical force field (QMFF).X-Pol is a general fragment method for electronic structure calculations based on the partition of a condensed-phase or macromolecular system into subsystems ("fragments") to achieve computational efficiency. Here, intrafragment energy and the mutual electronic polarization of interfragment interactions are treated explicitly using quantum mechanics. X-Pol can be used as a general, multilevel electronic structure model for macromolecular systems, and it can also serve as a new-generation force field. As a quantum chemical model, a variational many-body (VMB) expansion approach is used to systematically improve interfragment interactions, including exchange repulsion, charge delocalization, dispersion, and other correlation energies. As a quantum mechanical force field, these energy terms are approximated by empirical functions in the spirit of conventional molecular mechanics. This Account first reviews the formulation of X-Pol, in the full variationally correct version, in the faster embedded version, and with systematic many-body improvements. We discuss illustrative examples involving water clusters (which show the power of two-body corrections), ethylmethylimidazolium acetate ionic liquids (which reveal that the amount of charge transfer between anion and cation is much smaller than what has been assumed in some classical simulations), and a solvated protein in aqueous solution (which shows that the average charge distribution of carbonyl groups along the polypeptide chain depends strongly on their position in the sequence, whereas they are fixed in most classical force fields). The development of QMFFs also offers an opportunity to extend the accuracy of biochemical simulations to areas where classical force fields are often insufficient, especially in the areas of spectroscopy, reactivity, and enzyme catalysis. © 2014 American Chemical Society.

Zeng T.,University of Waterloo | Li H.,Jilin University | Roy P.-N.,University of Waterloo
Journal of Physical Chemistry Letters | Year: 2013

We present the first simulation study of bosonic clusters doped with an asymmetric top molecule. The path-integral Monte Carlo method with the latest methodological advance in treating rigid-body rotation [Noya, E. G.; Vega, C.; McBride, C. J. Chem. Phys.2011, 134, 054117] is employed to study a para-water impurity in para-hydrogen clusters with up to 20 para-hydrogen molecules. The growth pattern of the doped clusters is similar in nature to that of pure clusters. The para-water molecule appears to rotate freely in the cluster. The presence of para-water substantially quenches the superfluid response of para-hydrogen with respect to the space-fixed frame. © 2012 American Chemical Society.

Lu J.,Jilin University | Der Steen T.V.,Mayo Medical School | Tindall D.J.,Mayo Medical School
Nature Reviews Urology | Year: 2015

Androgen receptor splice variants (AR-Vs) - which are expressed in castration-resistant prostate cancer (CRPC) cell lines and clinical samples - lack the C-terminal ligand-binding domain and are constitutively active. AR-Vs are, therefore, resistant to traditional androgen deprivation therapy (ADT). AR-Vs are induced by several mechanisms, including ADT, and might contribute to the progression of CRPC and resistance to ADT. AR-Vs could represent a novel therapeutic target for prostate cancer, especially in CRPC.

Li H.,Jilin University | Wu L.,Jilin University
Soft Matter | Year: 2014

The introduction of metal centers to a supramolecular polymer system is an important approach to fabricate hybrid supramolecular polymers with synergistic properties between their inorganic and organic components, which is mainly realized through two strategies: one is the embedment of metal ions through metal-ligand coordination to form metallo-supramolecular polymers (MSPs); the other is using metal-containing clusters as hybrid building blocks to prepare clusto-supramolecular polymers (CSPs). The available paradigms of MSPs and CSPs not only exhibit the unique functions of metal centers but also hold the good processing ability and the stimuli-responsibility of dynamically bonded polymeric structures, thus representing a new class of hybrid soft materials. In this review, the development and recent progress of MSPs and CSPs are discussed in detail, including their structure design, synthetic procedures and related properties. Finally, challenges and potential areas in metal-containing supramolecular polymers are outlooked. This journal is © the Partner Organisations 2014.

Khan M.,Jilin University
International journal of biological sciences | Year: 2012

Isoalantolactone, a sesquiterpene lactone compound possesses antifungal, antibacteria, antihelminthic and antiproliferative activities. In the present study, we found that isoalantolactone inhibits growth and induces apoptosis in pancreatic cancer cells. Further mechanistic studies revealed that induction of apoptosis is associated with increased generation of reactive oxygen species, cardiolipin oxidation, reduced mitochondrial membrane potential, release of cytochrome c and cell cycle arrest at S phase. N-Acetyl Cysteine (NAC), a specific ROS inhibitor restored cell viability and completely blocked isoalantolactone-mediated apoptosis in PANC-1 cells indicating that ROS are involved in isoalantolactone-mediated apoptosis. Western blot study showed that isoalantolactone increased the expression of phosphorylated p38 MAPK, Bax, and cleaved caspase-3 and decreased the expression of Bcl-2 in a dose-dependent manner. No change in expression of phosphorylated p38 MAPK and Bax was found when cells were treated with isoalantolactone in the presence of NAC, indicating that activation of these proteins is directly dependent on ROS generation. The present study provides evidence for the first time that isoalantolactone induces ROS-dependent apoptosis through intrinsic pathway. Furthermore, our in vivo toxicity study demonstrated that isoalantolactone did not induce any acute or chronic toxicity in liver and kidneys of CD1 mice at dose of 100 mg/kg body weight. Therefore, isoalantolactone may be a safe chemotherapeutic candidate for the treatment of human pancreatic carcinoma.

Zhang Y.-L.,Jilin University | Zhang Y.-L.,Yonsei University | Xia H.,Jilin University | Kim E.,Yonsei University | Sun H.-B.,Jilin University
Soft Matter | Year: 2012

The surface wettability control of solid materials has been considered as an essential aspect of surface chemistry. In the past decade, superhydrophobic surfaces have revealed a cornucopia of novel structural and functional properties, exhibiting considerable importance in both fundamental research and practical applications. In this review, we summarize the recent developments of superhydrophobic surfaces with unique structural and functional properties. Both the fabricative methods and the working performance of superhydrophobic surfaces with multidisciplinary functionalities including self-cleaning, icephobicity, anti-corrosion, drag reduction, transparency, anti-reflection, structural color, droplet transportation, anisotropy, oil-water separation, water supporting force, superamphiphobicity and responsive switching, have been discussed briefly. Finally, the current challenges and future prospects of this dynamic field are discussed based on our own opinion. © 2012 The Royal Society of Chemistry.

Liu Y.,Jilin University
International journal of medical sciences | Year: 2012

Splenosis is not an uncommon disease. However, it is often misdiagnosed as malignant tumors, and then the patients underwent unnecessary operations. Unfortunately, it is very difficult to diagnose it prior to operation. We report a rare case of a 49-year-old female patient with liver and colon splenosis, misdiagnosed as liver and colon tumors, and summarize experience how to diagnose it preoperatively according to literatures. We come to conclusion that in patients who ever underwent splenectomy especially owning to trauma, and were found mass in abdomen, clinicians must consider the existence of splenosis, and take some measures, such as scintigraphy with (99m) Tc labelled heat-denatured erythrocyte rather than biopsy, to diagnose it correctly to prevent unnecessary operations.

Qu L.,Jilin University | Xu W.,Jilin University
Cancer Research and Clinic | Year: 2016

Malignant colon cells require angiogenesis and optimal tumor microenvironment for proliferation, invasion and metastasis. The non-receptor tyrosine kinase signal transducer and activator of transcription (JAK-STAT) pathway are involved in multiple processes, including chronic inflammation-associated tumorigenesis, cancer proliferation, tumor angiogenesis, immune evasion and facilitating tumor metastasis, making JAK-STAT a new target in molecular target therapy. In this review, advances on JAK-STAT pathway as a new target in colon tumorigenesis are updated, and a preliminary estimation of JAK-STAT in prognosis and target therapy will be mentioned to show a potential future of JAK-STAT in colon cancer. © Copyright 2016 by the Chinese Medical Association.

Liu H.,Jilin University | Liu L.,Jilin University | Zhang H.,Northeast Normal University
Pattern Recognition | Year: 2010

Cancer diagnosis is an important emerging clinical application of microarray data. Its accurate prediction to the type or size of tumors relies on adopting powerful and reliable classification models, so as to patients can be provided with better treatment or response to therapy. However, the high dimensionality of microarray data may bring some disadvantages, such as over-fitting, poor performance and low efficiency, to traditional classification models. Thus, one of the challenging tasks in cancer diagnosis is how to identify salient expression genes from thousands of genes in microarray data that can directly contribute to the phenotype or symptom of disease. In this paper, we propose a new ensemble gene selection method (EGS) to choose multiple gene subsets for classification purpose, where the significant degree of gene is measured by conditional mutual information or its normalized form. After different gene subsets have been obtained by setting different starting points of the search procedure, they will be used to train multiple base classifiers and then aggregated into a consensus classifier by the manner of majority voting. The proposed method is compared with five popular gene selection methods on six public microarray datasets and the comparison results show that our method works well. © 2010 Elsevier Ltd. All rights reserved.

Xi G.-L.,Jilin University | Liu Z.-Q.,Jilin University
Journal of Agricultural and Food Chemistry | Year: 2015

Two coumarin skeletons can form chromeno[3,4-c]chromene-6,7-dione by sharing with the C=C in lactone. The aim of the present work was to explore the antioxidant effectiveness of the coumarin-fused coumarin via six synthetic compounds containing hydroxyl and N,N-dimethylamino as the functional groups. The abilities to quench 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonate) cationic radical (ABTS+•), 2,2′-diphenyl-1-picrylhydrazyl radical (DPPH), and galvinoxyl radical revealed that the rate constant for scavenging radicals was related to the amount of hydroxyl group in the scaffold of coumarin-fused coumarin. But coumarin-fused coumarin was able to inhibit DNA oxidations caused by •OH, Cu2+/glutathione (GSH), and 2,2′-azobis(2-amidinopropane hydrochloride) (AAPH) even in the absence of hydroxyl group. In particular, a hydroxyl and an N,N-dimethylamino group locating at different benzene rings increased the inhibitory effect of coumarin-fused coumarin on AAPH-induced oxidation of DNA about 3 times higher than a single hydroxyl group, whereas N,N-dimethylamino-substituted coumarin-fused coumarin possessed high activity toward •OH-induced oxidation of DNA without the hydroxyl group contained. Therefore, the hydroxyl group together with N,N-dimethylamino group may be a novel combination for the design of coumarin-fused heterocyclic antioxidants. © 2015 American Chemical Society.

Ma D.-L.,CAS Changchun Institute of Applied Chemistry | Ma D.-L.,Jilin University | Cao Z.-Y.,Jilin University | Wang H.-G.,CAS Changchun Institute of Applied Chemistry | And 4 more authors.
Energy and Environmental Science | Year: 2012

A new hybrid nanostructure composed of three-dimensionally ordered macroporous (3DOM) FeF 3 and an homogenous coating of poly(3, 4-ethylenedioxythiophene) (PEDOT) is successfully synthesized using polystyrene (PS) colloidal crystals as hard template, and the coating of PEDOT is achieved through a novel in situ polymerization method. The special nanostructure provides a three-dimensional, continuous, and fast electronic and ionic path in the electrode. Surprisingly, the advantageous combination of 3DOM structure and homogenous coating of PEDOT endows the as-prepared hybrid nanostructures with a stable and high reversible discharge capacity up to 210 mA h g -1 above 2.0 V at room temperature (RT), and a good rate capability of 120 mA h g -1 at a high current density of 1 A g -1, which opens up new opportunities in the development of high performance next-generation lithium-ion batteries (LIBs). © 2012 The Royal Society of Chemistry.

Zhang S.-F.,Jilin University | Chen X.-K.,Jilin University | Fan J.-X.,Jilin University | Ren A.-M.,Jilin University
Organic Electronics: physics, materials, applications | Year: 2013

The charge transport properties in a series of five-ring-fused thienoacenes are detailedly investigated here. With both high 3-D hole mobilities and good oxidative stability, the thiophene-benzene alternate structures in series B should be better than other two series as p-type organic semiconductors. In addition, a theoretical explanation for the difference between experimental hole mobilities in B-3 and B-3- is provided based on crystal structure prediction. The role of dynamic disorder in C-3 is also investigated here and the results indicate that dynamic disorder plays a crucial role both in the 1-D and 2-D carrier transporting process. © 2012 Elsevier B.V. All rights reserved.

Dong T.,Jilin University
Journal of Systems Science and Complexity | Year: 2016

Farr-Gao algorithm is a state-of-the-art algorithm for reduced Gröbner bases of vanishing ideals of finite points, which has been implemented in Maple as a build-in command. This paper presents a two-dimensional improvement for it that employs a preprocessing strategy for computing reduced Gröbner bases associated with tower subsets of given point sets. Experimental results show that the preprocessed Farr-Gao algorithm is more efficient than the classical one. © 2016 Institute of Systems Science, Academy of Mathematics and Systems Science, CAS and Springer-Verlag Berlin Heidelberg

Liu S.,Jilin University | Hu J.,Jilin University | Zhang H.,Jilin University | Su X.,Jilin University
Talanta | Year: 2012

In this paper, a sensitive and simple method for the determination of melamine (MA) was developed based on the fluorescence changes of the water-soluble CuInS2 quantum dots (QDs). The water-soluble CuInS 2 QDs capped by mercaptopropionic acid (MPA) was directly synthesized by hydrothermal method based on our previous report. The fluorescence emission of CuInS2 QDs was quenched by the oxidation of the surface of the QDs with H2O2, and the quenched fluorescence of CuInS 2 QDs could be recovered upon the addition of small amounts of MA, which might be due to the surface passivation of the CuInS2 QDs by MA. The other amino acids such as glycine and lysine had no effect on the quenched fluorescence of CuInS2 QDs. Under optimum conditions, there was a good linear relationship between the fluorescence intensity of CuInS 2 QDs and the concentration range of MA from 1.0×10 -8 to 1.0×10-5 mol/L with a detection limit as low as 5 nM. The proposed method was successfully applied to detect trace MA in raw milk with satisfactory results. Compared with previous reports, the proposed method manifested several advantages such as high sensitivity, short analysis time, low cost and ease of operation. © 2012 Elsevier B.V. All rights reserved.

Zhuang H.,Jilin University | Tang N.,Jilin University | Yuan Y.,Jilin University
Journal of Functional Foods | Year: 2013

Corn gluten meal was hydrolyzed by alkaline protease and Flavourzyme to obtain the antioxidant peptides. The antioxidant activities of the hydrolysates or peptides were evaluated by free radical scavenging capacity (1,1-diphenyl-2-picrylhydrazyl/2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt/hydroxyl radical/superoxide radical anion), metal ion (Fe2+/Cu2+) chelating activity and lipid peroxidation inhibitory capacity. The hydrolysates were separated by ultrafiltration, and those with molecular weight <10kDa exhibited highest antioxidant activity in all relevant assays. The hydrolysates were subsequently purified by gel filtration chromatography, and fraction F3 showed the highest antioxidant activity. Three peptides were identified from fraction F3 using LC-ESI-Q-TOF MS/MS as Leu-Pro-Phe (375.46Da), Leu-Leu-Pro-Phe (488.64Da) and Phe-Leu-Pro-Phe (522.64Da). These peptides exhibited good free radical scavenging activity and lipid peroxidation inhibitory effect. Thus, corn gluten meal may be used as a potential source of antioxidant peptides for food and nutraceutical applications. © 2013 Elsevier Ltd.

Ren W.,Jilin University | Gu G.,Jilin University
European Journal of Cancer Care | Year: 2015

Primary osteosarcoma is the most frequent malignant bone cancer in children and teenagers. Genetic alterations at the retinoblastoma 1 (RB1) gene has been implicated in the development and progression of human osteosarcoma. Here, we performed a meta-analysis to examine the impact of RB1 mutations on the survival of osteosarcoma patients, the risk of metastasis and the histological response of osteosarcoma to chemotherapy. A systemic review of the Medline, Embase, Scopus and Cochrane Library yielded 12 eligible studies with 491 patients for this study. Forest plots resulting from our meta-analyses illustrate that loss of RB1 function results in a 1.62-fold increase in the mortality rate for osteosarcoma patients (RR = 1.62, 95% CI: 1.23-2.13; Z = 3.44, P = 0.0006), a significant increase in osteosarcoma metastasis (OR = 3.95, 95% CI: 1.86-8.38; Z = 3.57; P = 0.0004), and a significant reduction in the histological response of osteosarcoma to chemotherapy (OR = 0.35; 95% CI: 0.13-0.94; Z = -2.08; P = 0.038). Additionally, the nearly symmetrical funnel plot (Egger's test, t = 1.15, P = 0.288) indicates absence of publication bias regarding the meta-analysis that examined the correlation of RB1 alterations with the survival rate for osteosarcoma patients. Our findings suggest that RB1 alterations may serve as a prognostic marker for the management of osteosarcoma patients. © 2015 John Wiley & Sons Ltd.

Zhou J.-B.,Jilin University | Zhou J.-B.,Curtin University Australia | Wilde S.A.,Jilin University | Wilde S.A.,Curtin University Australia
Gondwana Research | Year: 2013

The basement rocks in parts of NE China constitute a khondalitic sequence of sillimanite- and garnet-bearing gneisses, hornblende-plagioclase gneiss and various felsic paragneisses. Zircon U-Pb dating of garnet-sillimanite gneiss samples from the Erguna, Xing'an, Jiamusi and Khanka blocks indicates that high-grade metamorphism occurred at ~ 500. Ma. Evidence from detrital zircons in Paleozoic sediments from the Songliao Block also indicates the former presence of a ~ 500. Ma component. This uniformity of U-Pb ages across all crustal blocks in NE China establishes a >. 1300. km long Late Pan-African khondalite belt which we have named the 'NE China Khondalite Belt'. This indicates the blocks of NE China were amalgamated prior to ~ 500. Ma, contrary to current belief. One scenario is that this amalgamated terrane had a tectonic affinity to the Siberia Craton, once forming part of the Late Pan-African (~ 500. Ma) Sayang-Baikal orogenic belt extensively developed around the southern margin of the Siberia Craton. This belt was the result of collision between currently unidentified terranes with the Southeastern Angara-Anabar Province at about 500. Ma, where the rocks were deformed and metamorphosed to granulite facies. It appears likely that at sometime after ~ 450. Ma, the combined NE China blocks rifted away from Siberia and moved southward to form what is now NE China. The combined block collided with the North China Craton along the Solonker-Xar Moron-Changchun suture zone at ~ 230. Ma rather than in the end-Permian as previously thought. Local rifting at the eastern extremity of the developing Central Asian Orogenic Belt (CAOB) resulted in the splitting away of the Jiamusi/Khanka(/Bureya) blocks. However, this was only transient and sometime between 210 and 180. Ma, these were re-united with the CAOB by the onset of Pacific plate subduction, which has dominated the tectonic evolution of the region since that time. © 2012 International Association for Gondwana Research.

Liu Y.,Jilin University | Liu Y.,University of Texas at Austin | Fomel S.,University of Texas at Austin
Geophysical Prospecting | Year: 2013

Many natural phenomena, including geologic events and geophysical data, are fundamentally nonstationary - exhibiting statistical variation that changes in space and time. Time-frequency characterization is useful for analysing such data, seismic traces in particular. We present a novel time-frequency decomposition, which aims at depicting the nonstationary character of seismic data. The proposed decomposition uses a Fourier basis to match the target signal using regularized least-squares inversion. The decomposition is invertible, which makes it suitable for analysing nonstationary data. The proposed method can provide more flexible time-frequency representation than the classical S transform. Results of applying the method to both synthetic and field data examples demonstrate that the local time-frequency decomposition can characterize nonstationary variation of seismic data and be used in practical applications, such as seismic ground-roll noise attenuation and multicomponent data registration. © 2012 European Association of Geoscientists & Engineers.

Lai H.-W.,Jilin University | Liu Z.-Q.,Jilin University
European Journal of Medicinal Chemistry | Year: 2014

4-Thiaflavan is a sulfur-substituted flavonoid with a benzoxathiin scaffold. The aim of this work is to compare abilities of sulfur and oxygen atom, hydroxyl groups, and ferrocene moiety at different positions of 4-thiaflavan to trap radicals and to inhibit DNA oxidation. It is found that abilities of thiaflavans to trap radicals and to inhibit DNA oxidation are increased in the presence of ferrocene moiety and are further improved by the electron-donating group attaching to thiaflavan skeleton. It can be concluded that the ferrocene moiety plays the major role for thiaflavans to be antioxidants even in the absence of phenolic hydroxyl groups. On the other hand, the antioxidant effectiveness of phenolic hydroxyl groups in thiaflavans can be improved by the electron-donating group. The influences of sulfur and oxygen atoms in thiaflavans on the antioxidant property of para-hydroxyl group exhibit different manners when the thiaflavans are used to trap radicals and to inhibit DNA oxidation. © 2014 Elsevier Masson SAS. All rights reserved.

Xi G.-L.,Jilin University | Liu Z.-Q.,Jilin University
European Journal of Medicinal Chemistry | Year: 2014

Twenty-two 2-phenyl-4-ferrocenylquinolines are synthesized by Povarov three-component-reaction (3CR) among the substituted anilines, benzaldehydes, and ferrocenylacetylene with Ce(OTf)3 being catalyst in the absence of solvents. The antioxidative effects of the obtained quinolines are estimated by quenching 2,2€2-azinobis(3-ethylbenzothiazoline-6-sulfonate) cationic radical (ABTS+), 2,2#x020AC;2-diphenyl-1-picrylhydrazyl (DPPH), and galvinoxyl radicals, and by inhibiting Cu2+/glutathione (GSH)-, hydroxyl radical (OH)-, and 2,2#x020AC;2-azobis(2-amidinopropane hydrochloride) (AAPH)-induced oxidations of DNA. It is found that the ferrocenyl group instead of hydroxyl group generates the antioxidative effect for quinoline to quench radicals and to protect DNA against radical-induced oxidations. The antioxidative effect generated by ferrocenyl group can be further increased by the electron-donating moieties such as furan, -N(CH3)2, -OCH3, and ferrocenyl group, while the electron-withdrawing groups such as -NO2 and -Cl are not beneficial for quinolines to be antioxidants. The ferrocenyl group in quinoline exhibits higher antioxidant activity than hydroxyl group in Trolox. © 2014 Elsevier Masson SAS.

Li X.,Changchun University of Chinese Medicine | Dong S.,Jilin University
Medical Oncology | Year: 2015

JMJD2B and JMJD2C, histone demethylases, play crucial roles in cancer development and are up-regulated in many cancers. However, the actions of JMJD2B and JMJD2C in osteosarcoma remain unknown. The levels of JMJD2B or JMJD2C were evaluated in osteosarcoma cells and tissues via quantitative real-time PCR and Western Blot. JMJD2B and JMJD2C were up-regulated in osteosarcoma tissues when compared to paired adjacent non-tumor tissues. A higher level of JMJD2B or JMJD2C was related with metastasis of osteosarcoma cells. Fibroblast growth factor 2 (FGF2) is an important factor to maintain immaturity of cells and contributes to osteosarcoma aggressiveness. Elevated levels of FGF2 promoted the proliferation, migration, and invasion of osteosarcoma cell, while FGF2 was up-regulated by JMJD2B or JMJD2C. GST pull-down assay showed that JMJD2B or JMJD2C interacted with FGF2. Thus, JMJD2B and JMJD2C play an important role in the pathology of osteosarcoma via the up-regulation of FGF2. JMJD2B and JMJD2C should be developed potential targets for the therapy of osteosarcoma patients. © 2015, Springer Science+Business Media New York.

Chen H.-L.,Jilin University | Yang B.,Jilin University | Liu J.,Jilin University | Liu D.-Y.,Jilin University
Expert Systems with Applications | Year: 2011

Breast cancer is becoming a leading cause of death among women in the whole world, meanwhile, it is confirmed that the early detection and accurate diagnosis of this disease can ensure a long survival of the patients. Expert systems and machine learning techniques are gaining popularity in this field because of the effective classification and high diagnostic capability. In this paper, a rough set (RS) based supporting vector machine classifier (RS-SVM) is proposed for breast cancer diagnosis. In the proposed method (RS-SVM), RS reduction algorithm is employed as a feature selection tool to remove the redundant features and further improve the diagnostic accuracy by SVM. The effectiveness of the RS-SVM is examined on Wisconsin Breast Cancer Dataset (WBCD) using classification accuracy, sensitivity, specificity, confusion matrix and receiver operating characteristic (ROC) curves. Experimental results demonstrate the proposed RS-SVM can not only achieve very high classification accuracy but also detect a combination of five informative features, which can give an important clue to the physicians for breast diagnosis. © 2011 Elsevier Ltd. All rights reserved.

The important differences in physiological parameters and anatomical characteristics of the kidney between humans and mice make it difficult to replicate the precise progression of human renal cystic diseases in gene modification mouse models. In contrast to mice, pigs are a better animal model of human diseases, as they are more similar in terms of organ size, structure, and physiological parameters. Here, we report the generation and initial examination of an AQP2-Cre transgenic (Tg) Chinese miniature (mini)-pig line that expresses Cre recombinase exclusively in kidney collecting duct cells. An 8-kb fragment of the mini-pig aquaporin 2 (AQP2) 5'-flanking region was utilized to direct Cre expression in Tg mini-pigs. Two Tg mini-pigs were generated by pig somatic cell nuclear transfer and both carried the entire coding sequence of Cre recombinase. RT-PCR and western blotting analysis revealed that Cre recombinase was uniquely expressed in the kidney, while immunohistochemical studies located its expression in kidney collecting duct cells. Furthermore, six integration sites and 12-14 copies of the Cre gene were detected in various tissues by high-efficiency thermal asymmetric interlaced PCR and absolute quantitative real-time PCR, respectively. Combined with previous studies of Cre recombinase activity, we believe that this AQP2-Cre Tg mini-pig line will be a useful tool to generate kidney collecting duct cell-specific gene knockout mini-pig models, thereby allowing the investigation of gene functions in kidney development and the mechanisms of human renal cystic disease.

Sun Y.-L.,Jilin University | Liu D.X.,Jilin University | Dong W.-F.,Jilin University | Chen Q.D.,Jilin University | Sun H.B.,Jilin University
Optics Letters | Year: 2012

Herein, tunable protein harmonic diffractive microlenses (PHDMs) have been constructed by femtosecond laser direct writing from bovine serum albumin. With excellent three-dimensional topography, PHDMs show distinct harmonic diffractive features, such as similarly good imaging performance with smaller thickness than refractive lenses and well controlled minus chromatic dispersion compared with simple diffractive lenses (∼5% focal length shift against ∼21% of the protein Fresnel zone plate with the same radius under light with wavelength 450-659 nm). Owing to the nature of protein molecules as "building blocks," the focal length of the PHDM can be facilely tuned within seconds by changing the pH value (focal length tunability of up to ∼20%). © 2012 Optical Society of America.

Peng F.,Jilin University | Peng F.,Luoyang Normal University | Miao M.,University of California at Santa Barbara | Wang H.,Jilin University | And 2 more authors.
Journal of the American Chemical Society | Year: 2012

High pressure can fundamentally alter the bonding patterns of light elements and their compounds, leading to the unexpected formation of materials with unusual chemical and physical properties. Using an unbiased structure search method based on particle-swarm optimization algorithms in combination with density functional theory calculations, we investigate the phase stabilities and structural changes of various Li-B systems on the Li-rich regime under high pressures. We identify the formation of four stoichiometric lithium borides (Li3B2, Li2B, Li4B, and Li6B) having unforeseen structural features that might be experimentally synthesizable over a wide range of pressures. Strikingly, it is found that the B-B bonding patterns of these lithium borides evolve from graphite-like sheets in turn to zigzag chains, dimers, and eventually isolated B ions with increasing Li content. These intriguing B-B bonding features are chemically rationalized by the elevated B anionic charges as a result of LiB charge transfer. © 2012 American Chemical Society.

The layer-by-layer (LbL) codeposition of polyelectrolyte-polyelectrolyte complexes (PECs) and free polyelectrolytes with oppositely charged polyelectrolytes for the fabrication of polymeric films has been systematically investigated. Aqueous dispersions containing positively charged diazoresin (DAR)poly(acrylic acid) (PAA) complexes (denoted as DAR-PAA) and free DAR were used as the dipping solutions for LbL film fabrication with PAA. Simultaneous deposition of DAR-PAA complexes and free DAR with PAA took place under a nondrying LbL deposition process that produced bilayered thick polymeric films with the hierarchical PAA/DAR-PAA coatings rooting in the underlying continuous PAA/DAR films. The structure of the bilayered polymeric films depends largely on the ratio of DAR-PAA complexes to free DAR in the dipping solution. The more rapid deposition of PAA/DAR-PAA coatings than that of the PAA/DAR films accounts for the formation of bilayered polymeric films because DAR-PAA complexes have larger dimensions than DAR in solution. The bilayered polymeric coatings with hierarchical structures rooting in continuous films have enhanced adhesion with the underlying substrates because of the increased contacting area. After chemical vapor deposition of a layer of fluoroalkylsilane, the bilayered polymeric coatings can be easily converted into superhydrophobic. In contrast, the LbL codeposition of DAR-PAA complexes and DAR with PAA produces thin and compact films without bilayered structures when a N2 drying step is conducted after each layer deposition. The present study is meaningful in deeply understanding the deposition behavior and structure tailor of LbL assembled films using PECs as building blocks. © 2010 American Chemical Society.

Zhang Z.,Baicheng Normal College | Zhang Z.,Jilin University
Inorganic Chemistry Communications | Year: 2012

Silver atoms and strongly interlinking α-metatungstate units ensure the 3D structure of (NH 4) 5[Ag 5(L) 2(H 2O) 8(H 2W 12O 40)]•H 2O (L = pyridine-3,5-dicarboxylate dianion), which has been synthesized in aqueous solution and characterized by the normal physical methods as well as the single-crystal X-ray diffraction. This compound represents the first example that the α-metatungstate cluster as the structural motif is linked by transition metal complexes to yield unprecedented 3D framework with the highest eleven-connected number. © 2011 Elsevier B.V. All rights reserved.

Zhao K.,Jilin University
Proceedings - 2014 7th International Conference on BioMedical Engineering and Informatics, BMEI 2014 | Year: 2014

Hexavalent chromium Cr(VI) has been widely used in metal pickling and plating, which induces cancer and coetaneous allergy in the long time exposure. In this work, a novel thin film composite hollow fiber nanofiltration (NF) membrane was developed, which was optimized by time of interfacial polymerization, concentration of monomers and the IP process. In addition, operational conditions, including PH values, temperatures and operational pressures on the NF performance was further investigated to exhibit potential application in the industrial wastewater treatment and obtained resultant water for biomedical use. © 2014 IEEE.

Hou G.,Jilin University | Bi L.,Jilin University | Li B.,Jilin University | Wu L.,Jilin University
Inorganic Chemistry | Year: 2010

To investigate the influence of reaction conditions on the compound structures, five polyoxometalate (POM)-supported Inorganic-organic hybrid compounds, [Cul 3(L1)4][PW 12O40] (1). [Cul 3(L 1)4][PMO12O40] (2), [Cu l 3(L1)4][PW12O 40] (3), [Cul 3(L1) 3][PW12O40] (4), and [Cu3(L 2)3][PMO12O40] (5) [L1 = 1,4-bis(pyrazol-1-ylmethyl)benzene, L2 = 4,4′bis(pyrazol-1 -ylmethyl)biphenyl], were hydrothermally synthesized by tuning the reactant species and molar ratio and reaction temperature and were characterized by elemental analysis, IR spectroscopy, PXRD, XPS, electrochemistry. SPS, and X-ray crystallography. Compounds 1 and 2 were synthesized in the isostructural state at 150°C, In which L1 ligands link Cul ions, generating a catlonic 2D 63 (hcb) skeleton {[Cu3(L 1)4]3+}n-like sheet that further connects with POM anions, forming a neutral 2D (3,4)-connected network with a Schläfli symbol of (53)2(54;8 2). In contrast, compound 3 was synthesized at a relatively lower reaction temperature (130°C) than that for the synthesis of 1 and 2, which exhibits a similar 2D sheet-like cationic skeleton with 1 and 2. Interestingly, the POM anions do not coordinate with the cationic moieties in 3. Compounds 4 and 5 were synthesized with a relatively lower reactant molar ratio In comparison with that for the synthesis of 1-3, In which the cationic coordination moieties all present 1D chain-like structures. Compound 4 exhibits a 3D (3,4)-connected sqc74 framework with a Schläfli symbol of (6;8 2)(64;8;10) formed by the POM anions linking {[Cu 3(L1)3]3+}n cationic chains. In comparison to 4, compound 5 shows a 3D supramolecular framework,.which is formed by POM anions and {[Cu3(L 2)3]3+}n catlonic chains via hydrogen bonds. The structural difference of compounds 1-5 indicates that the reaction conditions perform a crucial Influence on the structures of this series. The electrochemical properties of 2 and 5 and the SPS responses of 3-5 suggest that these compounds can be used as potential electrocatalytic or photocatalytic framework materials. In addition, EFISPS curves Indicate that 3-5 possess the n-type semiconductor characteristic. © 2010 American Chemical Society.

Zhang H.,Jilin University | Wei A.,Jilin University | Qiu X.,Jilin University | Chen J.,Sanyou Automobile Parts Manufacturing Co.
Materials and Design | Year: 2014

In this study, resistance spot welding (RSW) experiments were performed in order to evaluate the microstructure and mechanical properties of single-lap joints between DP780 and DP600. The results show that the weld joints consist of three regions including base metal (BM), heat affected zone (HAZ) and fusion zone (FZ). The grain size and martensite volume fractions increase in the order of BM, HAZ and FZ. The hardness in the FZ is significantly higher than hardness of base metals. Tensile properties of the joints were described in terms of the failure modes and static load-carrying capabilities. Two distinct failure modes were observed during the tensile shear test of the joints: interfacial failure (IF) and pullout failure (PF). The FZ size plays a dominate role in failure modes of the joints. © 2013 Elsevier Ltd.

Li B.,University of South Florida | Zhang Y.,University of South Florida | Ma D.,Jilin University | Ma T.,Jilin Agricultural University | And 2 more authors.
Journal of the American Chemical Society | Year: 2014

In this work, a new strategy is developed to encapsulate a metal-functionalized guest molecule into a metal-organic framework (MOF) via metal-cation-directed de novo assembly from the component fragments of the guest molecule. This strategy, as illustrated in proof-of-principle studies on the de novo assembly of metal(II) phthalocyanine molecules into bio-MOF-1, can circumvent some drawbacks of existing approaches for encapsulating guest molecules into MOFs, such as inaccessibility for larger guest molecules due to limitations of the MOF window size and disruption of the MOF framework structure by functionalized guest molecules. Overall, this work provides a general yet versatile approach for encapsulating a broader range of metal-functionalized guest molecules into MOFs for various applications. © 2014 American Chemical Society.

Liu Y.,University of Maryland University College | Li Y.,Jilin University | He J.,University of Maryland University College | Duelge K.J.,University of Maryland University College | And 2 more authors.
Journal of the American Chemical Society | Year: 2014

Although an analogy has been drawn between them, organic molecular amphiphiles (MAMs) and inorganic nanoparticle (NP) amphiphiles (NPAMs) are significantly different in dimension, geometry, and composition as well as their assembly behavior. Their concurrent assembly can synergetically combine the inherent properties of both building blocks, thus leading to new hybrid materials with increasing complexity and functionality. Here we present a new strategy to fabricate hybrid vesicles with well-defined shape, morphology, and surface pattern by coassembling MAMs of block copolymers (BCPs) and NPAMs comprising inorganic NPs tethered with amphiphilic BCPs. The assembly of binary mixtures generated unique hybrid Janus-like vesicles with different shapes, patchy vesicles, and heterogeneous vesicles. Our experimental and computational studies indicate that the different nanostructures arise from the delicate interplay between the dimension mismatch of the two types of amphiphiles, the entanglement of polymer chains, and the mobility of NPAMs. In addition, the entropic attraction between NPAMs plays a dominant role in controlling the lateral phase separation of the two types of amphiphiles in the membranes. The ability to utilize multiple distinct amphiphiles to construct discrete assemblies represents a promising step in the self-assembly of structurally complex functional materials. © 2014 American Chemical Society.

Van Humbeck J.F.,University of California at Berkeley | McDonald T.M.,University of California at Berkeley | Jing X.,Jilin University | Wiers B.M.,University of California at Berkeley | And 3 more authors.
Journal of the American Chemical Society | Year: 2014

The elimination of specific environmental and industrial contaminants, which are hazardous at only part per million to part per billion concentrations, poses a significant technological challenge. Adsorptive materials designed for such processes must be engendered with an exceptionally high enthalpy of adsorption for the analyte of interest. Rather than relying on a single strong interaction, the use of multiple chemical interactions is an emerging strategy for achieving this requisite physical parameter. Herein, we describe an efficient, catalytic synthesis of diamondoid porous organic polymers densely functionalized with carboxylic acids. Physical parameters such as pore size distribution, application of these materials to low-pressure ammonia adsorption, and comparison with analogous materials featuring functional groups of varying acidity are presented. In particular, BPP-5, which features a multiply interpenetrated structure dominated by <6 Å pores, is shown to exhibit an uptake of 17.7 mmol/g at 1 bar, the highest capacity yet demonstrated for a readily recyclable material. A complementary framework, BPP-7, features slightly larger pore sizes, and the resulting improvement in uptake kinetics allows for efficient adsorption at low pressure (3.15 mmol/g at 480 ppm). Overall, the data strongly suggest that the spatial arrangement of acidic sites allows for cooperative behavior, which leads to enhanced NH3 adsorption. © 2014 American Chemical Society.

Liu D.-R.,Jilin University | Jiang Y.-S.,Jilin University | Gao G.-M.,Jilin University
Chemosphere | Year: 2011

N-doped NaTaO 3 compounds (NaTaO 3-xN x) with nano-cubic morphology were successfully synthesized by one-step hydrothermal method and Methyl Orange (MO) was used as a model dye to evaluate their photocatalytic efficiency under visible-light irradiation. The as-prepared NaTaO 3-xN x samples were characterized by various techniques, such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and UV-vis diffuse reflectance spectra and GC-MS. The results indicate that NaTaO 3-xN x displays a pure perovskite structure when the synthesis temperature is higher than 180°C. Moreover, as observed by SEM images, the particles of resultant NaTaO 3-xN x show cubic morphology with the edge length of 200-500nm, which can be easily removed by filtration after photocatalytic reaction. Doping of N increases the photocatalytic activity of NaTaO 3, and NaTaO 2.953N 0.047 shows the highest visible-light photocatalytic activity for the degradation of MO. Based on the experiment results, a possible mechanism of the photocatalysis over NaTaO 3-xN x and the photodegradation pathway of MO were proposed. © 2011 Elsevier Ltd.

Hou N.,Jilin University | Wu D.,Jilin University | Li Y.,Jilin University | Li Z.-R.,Jilin University
Journal of the American Chemical Society | Year: 2014

A new kind of cationic superatom compounds (M-F)+ (M = OLi 4, NLi5, CLi6, BLi7, and Al 14) with low vertical electron affinities (VEA) has been designed based on the distinctive electronic structure of superalkaline-earth atom. The stability of the studied superatom architectures is guaranteed by strong M-fluorine interactions, considerable HOMO-LUMO gaps, as well as large dissociation energies. What is extraordinary is that fluorination plays an important role in lowering the VEA value of M+ and enables the resulting (M-F)+ fluorides to join the superalkali family. However, the same strategy does not work as well for the alkaline-earth atoms whose valence electrons are more tightly bound. The comparative study on (OLi 4-X)+ (X = F, Cl, Br) reveals that fluorination is more effective than chlorination and bromination to reduce the VEA value of the OLi4+ cation. As for the (Al14-X)+ species, there is no obvious dependence of VEA values on halogen atomic number. © 2014 American Chemical Society.

Ge X.-L.,Jilin University | Du H.,Jilin University | Guo J.,Jilin University | Liu X.-S.,Jilin University
Optics Express | Year: 2015

By solving a two-dimensional time-dependent Schrödinger equation we investigate high harmonic generation (HHG) and isolated attosecond pulse generation for the H2+ molecular ion in a circularly polarized laser pulse combined with a Terahertz (THz) field. The harmonic intensity can be greatly enhanced and a continuum spectrum can be obtained when a THz field is added. The HHG process is studied by the semi-classical threestep model and the time-frequency analysis. Our studies show that only short trajectories contribute to HHG. Furthermore, we present the temporal evolution of the probability density of electron wave packet, which perfectly shows a clear picture of the electron's two-time recombination when a THz field is added, and it is the main mechanism of HHG. By superposing the harmonics in the range of 216-249 eV, an isolated attosecond pulse with a duration of about 69 attoseconds can be generated. © 2015 Optical Society of America.

Nie H.,Jilin University | Zhao Y.,Jilin University | Zhang M.,Jilin University | Ma Y.,Jilin University | And 2 more authors.
Chemical Communications | Year: 2011

A novel fluorescent poly(2,7-carbazole) with a 4-[tris-(4-octyloxyphenyl) methyl]phenyl side chain is used to detect the explosive compounds TNT and DNT. It shows high recycled fluorescence quenching sensitivity, which is due to its strong electron donating ability and weaker interaction between the polymer chains caused by the bulky side chain. © 2011 The Royal Society of Chemistry.

Meng L.,Jilin University | Chen D.,Jilin University | Yang Y.,Jilin University | Zheng Y.,Jilin University | Hui R.,Chinese Academy of Sciences
Journal of Hypertension | Year: 2012

Background: It has long been known that depression is associated with hypertension but whether depression is a risk factor for hypertension incidence is still inconclusive. Objectives: To assess whether depression increases the incidence of hypertension. METHOD:: Literatures were searched from PubMed, EMBASE, Cochrane and PsycINFO without language restrictions. Any prospective cohort study was included, which reported the correlation between depression and incidence of hypertension in apparently healthy normotensive individuals. At baseline, the studies which had at least one self-report or interview-based assessment on depressive symptoms/disorders were selected. The definition of hypertension was defined as a repeatedly elevated blood pressure exceeding 140 (systolic) and/or over 90 mmHg (diastolic) determined in interview, use of antihypertensive medications, or self-reported or recorded diagnosed hypertension. Studies with cross-sectional or case-control design were excluded. Data abstraction was conducted independently by two authors. Results: Seventy-five full texts were initially searched, but only nine studies met our inclusion criteria, and they were comprised of 22 367 participants with a mean follow-up period of 9.6 years. We found that depression increased the risk of hypertension incidence [adjusted relative risk 1.42, 95% confidence interval (CI) 1.09 to 1.86, P = 0.009] and the risk was significantly correlated with the length of follow-up (P = 0.0002) and the prevalence of depression at baseline (P < 0.0001). Conclusions: Our meta-analysis supports that depression is probably an independent risk factor of hypertension. It is important to take depression into consideration during the process of prevention and treatment of hypertension. Further studies are needed to exclude the effects of other confounding factors. © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Cisplatin resistance is a difficult problem in clinical chemotherapy, and the mechanisms involved in cisplatin resistance require further study. In this study, we investigated the role of chloride channel-3 (ClC-3) in cisplatin resistance. Autophagy was demonstrated by accumulation of LC3-II, beclin 1 and Atg12-Atg5. The ultrastructure changes were observed under electron microscope. Chemical staining with acridine orange or MDC was used to detect acidic vesicular organelles. Quantification of apoptosis was detected by PI and Annexin V staining. The mechanisms involved in the Akt pathway and autophagy were studied by western blot analysis. Our results showed that Akt phosphorylation and autophagy were induced by cisplatin in human glioma U251 cells. Specific inhibition of ClC-3 by ClC-3 siRNA sensitized the apoptosis-resistant U251 cells to cisplatin-mediated cell death and downregulated phosphorylated Akt. Interestingly, ClC-3 suppression also inhibited induction of autophagy by cisplatin although the Akt/mTOR pathway was deregulated. Counteracting the autophagic process by 3-methylademine enhanced cytotoxicity of cisplatin, revealing that autophagy plays a key role in chemoresistance. Suppressing the Akt/mTOR pathway by the NADPH oxidase inhibitor diphenyl iodonium (DPI) indicated that cisplatin-induced activation of Akt/mTOR pathway requires generation of reactive oxygen species (ROS) through NADPH oxidase. Collectively, our results suggest that ClC-3 suppression causes the inhibition of Akt and autophagy, which can enhance the therapeutic benefit of cisplatin in U251 cells. Copyright © 2013 Wiley Periodicals, Inc.

Li C.,Jilin University | Zhou X.,Jilin University
Clinica Chimica Acta | Year: 2012

The presence of a complex population of gene transcripts in mature human sperm is well established, and numerous mRNAs and non-coding mRNAs have been identified in sperm of men and other mammalian species using microarray and RT-PCR. The traditional concept that RNAs in mature sperm are only remnants from spermatogenesis and have no biological functions is in doubt. The findings that reverse transcriptases in sperm are active and that sperm can independently activate translation of stored mRNAs suggest that sperm RNAs may have significant effects on male fertility. The differences in expression profiles among RNAs in mature sperm from fertile and infertile men, and the regulation of sperm RNAs in embryonic development make them appealing markers for therapeutic and diagnostic tools in male infertility. In this review, methods for the detection and description of the diversity of gene transcript in sperm are discussed along with their putative roles in functional aspects of sperm and in embryogenesis. © 2012 Elsevier B.V.

Tang G.,Jilin University | Du L.,Jilin University | Su X.,Jilin University
Food Chemistry | Year: 2013

In this paper, we constructed the fluorescence resonance energy transfer (FRET) system between MPAcapped CdTe quantum dots (QDs) and Rhodamine B (RB) in the environment of cetyltrimethylammonium bromide (CTAB). In this system, CdTe QDs were treated as energy donors, whilst RB was treated as energy acceptor. CTAB was used to make the distance between the particles of CdTe QDs and RB closer to improve the efficiency of FRET system. We optimized some important factors which would affect the efficiency of FRET system. Under the optimized experimental conditions, melamine (MB) could be detected based on the fluorescence intensity changes of RB in the FRET system. We could get a linear relationship between the fluorescence intensity of RB and the concentration of MB in the range of 0.05-4.0 μmol/L and the detection limit was 0.01 μmol/L. The proposed method was applied for the determination of melamine in milk samples with satisfactory results. © 2013 Elsevier Ltd.

Li M.,Jilin University
Environmental technology | Year: 2011

The reductive degradation of nitrobenzene (NB) by iron-carbon micro-electrolysis packing was investigated. The influence of initial NB concentration, pH value and packing amount on the removal rate of NB were studied. The results showed that the reaction with packing followed the pseudo-first-order reaction. The optimum pH was 3.0 for the degradation of NB in the tested pH ranges of 3-9 and the optimum packing amount was 40 g/200 ml. The flow-through column packed with packing was designed to remove NB from simulated wastewater for approximately 68 days. The removal rate was over 90% within initial periods. It could be seen that after running for 68 days, the packing still had good performance after the long-term column experiment. In addition, the changes of the packing surfaces morphologies and matters before, during and after the column experiment were analysed by scanning electron microscopy in conjunction with energy-dispersion spectroscopy (EDS).

Cui Z.-H.,Jilin University | Contreras M.,University of Guanajuato | Ding Y.-H.,Jilin University | Merino G.,University of Guanajuato
Journal of the American Chemical Society | Year: 2011

In this study, we analyzed CB4 and its cation, CB 4 +. Using CCSD(T)/aug-cc-pVQZ//CCSD(T)/aug-cc-pVTZ quantum-chemical calculations, we found that the neutral molecule is in accord with the results of Boldyrev and Wang, having a Cs global minimum with a planar tricoordinate carbon structure, contradicting previous studies. In contrast, CB4 +, which was reported by an early mass spectroscopic study, has a planar tetracoordinate carbon (ptC) atom, demonstrating that a modification of the charge can promote the stabilization of a ptC structure. © 2011 American Chemical Society.

Gao P.,Jilin University
IMA Journal of Mathematical Control and Information | Year: 2016

This paper is concerned with the optimal distributed control problem of the Kuramoto-Sivashinsky equation with pointwise state constraints and coupled integral state-control constraints. Based on perturbation methods of modern variational analysis and Ekeland's variational principle, the Pontryagin's minimum principle of this system is proved. The main difficulty in this paper is to deal with the non-linear term in the Kuramoto-Sivashinsky equation. © The Authors 2015. Published by Oxford University Press on behalf of the Institute of Mathematics and its Applications. All rights reserved.

Li Q.,Jilin University | Li Q.,University of Nevada, Las Vegas | Zhou D.,Jilin University | Zhou D.,University of Nevada, Las Vegas | And 3 more authors.
Physical Review Letters | Year: 2013

Tungsten borides are among a distinct class of transition-metal light-element compounds with superior mechanical properties that rival those of traditional superhard materials. An in-depth understanding of these compounds, however, has been impeded by uncertainties regarding their complex crystal structures. Here, we examine a wide range of chemical compositions of tungsten borides using a recently developed global structural optimization approach. We establish thermodynamically stable structures and identify a large number of metastable phases. These results clarify and correct previous structural assignments and predict new structures for possible synthesis. Our findings provide crucial insights for understanding the rich and complex crystal structures of tungsten borides, which have broad implications for further exploration of this class of promising materials. © 2013 American Physical Society.

Liu S.,Jilin University | Zhang H.,Jilin University | Qiao Y.,Jilin University | Su X.,Jilin University
RSC Advances | Year: 2012

In this paper, we present a novel and simple hydrothermal synthesis method for preparing water soluble high quality ternary CuInS 2 quantum dots (QDs) with mercaptopropionic acid (MPA) as the stabilizer. The influences of various experimental variables, including the precursor concentrations, reaction time, reaction temperature, pH value, the MPA/Cu molar ratio, as well as the kind of capping ligand used on the luminescent properties of the obtained ternary CuInS 2 QDs have been systematically investigated. The stable ternary CuInS 2 QDs with good photoluminescence emission properties and narrow size distribution can be obtained under optimum experimental conditions. It was used to label liver cancer cells. The optical features and structure of the obtained CuInS 2 QDs have been characterized by UV-vis and fluorescence spectroscopy, TEM, XRD, FT-IR and EDX. The proposed synthesis method was simple, low cost, with comparatively low reaction temperature (150 °C), and the as-synthesized near-infrared CuInS 2 QDs was proven to have excellent photostability. The synthesized CuInS 2 QDs is a promising fluorescent probe for biological and biomedical imaging due to its bandgap in the near infrared and the absence of toxic heavy metal ions. © 2012 The Royal Society of Chemistry.

Liu H.,Jilin University | Ma Y.,Jilin University
Physical Review Letters | Year: 2013

The recent discovery of phase IV of solid hydrogen and deuterium consisting of two alternate layers of graphenelike three-molecule rings and unbound H 2 molecules have generated great interest. However, the vibrational nature of phase IV remains poorly understood. Here, we report a peculiar proton or deuteron transfer and a simultaneous rotation of three-molecule rings in graphenelike layers predicted by ab initio variable-cell molecular dynamics simulations for phase IV of solid hydrogen and deuterium at pressure ranges of 250-350 GPa and temperature range of 300-500 K. This proton or deuteron transfer is intimately related to the particular elongation of molecules in graphenelike layers, and it becomes more pronounced with increasing pressure at the course of larger elongation of molecules. As the consequence of proton transfer, hydrogen molecules in graphenelike layers are short lived and hydrogen vibration is strongly anharmonic. Our findings provide direct explanations on the observed abrupt increase of Raman width at the formation of phase IV and its large increase with pressure. © 2013 American Physical Society.

Luo W.,Fudan University | Ma Y.,Jilin University | Gong X.,Fudan University | Xiang H.,Fudan University
Journal of the American Chemical Society | Year: 2014

A method based on the particle swarm optimization algorithm is presented to design quasi-two-dimensional materials. With this development, various single-layer and bilayer materials of C, Si, Ge, Sn, and Pb were predicted. A new Si bilayer structure is found to have a more favored energy than the previously widely accepted configuration. Both single-layer and bilayer Si materials have small band gaps, limiting their usages in optoelectronic applications. Hydrogenation has therefore been used to tune the electronic and optical properties of Si layers. We discover two hydrogenated materials of layered Si8H2 and Si6H2 possessing quasidirect band gaps of 0.75 and 1.59 eV, respectively. Their potential applications for light-emitting diode and photovoltaics are proposed and discussed. Our study opened up the possibility of hydrogenated Si layered materials as next-generation optoelectronic devices. © 2014 American Chemical Society.

Vantomme G.,CNRS Institute of Science and Supramolecular Engineering | Jiang S.,CNRS Institute of Science and Supramolecular Engineering | Jiang S.,Jilin University | Lehn J.-M.,CNRS Institute of Science and Supramolecular Engineering
Journal of the American Chemical Society | Year: 2014

Constitutional dynamic libraries of hydrazones aAbB and acylhydrazones aAcC undergo reorganization and adaptation in response to a chemical effector (metal cations) or a physical stimulus (light). The set of hydrazones [1A1B, 1A2B, 2A1B, 2A 2B] undergoes metalloselection on addition of zinc cations which drive the amplification of Zn(1A2B)2 by selection of the fittest component 1A2B. The set of acylhydrazones [E-1A1C, 1A2C, 2A1C, 2A2C] undergoes photoselection by irradiation of the system, which causes photoisomerization of E- 1A1C into Z-1A1C with amplification of the latter. The set of acyl hydrazones [E-1A1C, 1A3C, 2A1C, 2A 3C] undergoes a dual adaptation via component exchange and selection in response to two orthogonal external agents: a chemical effector, metal cations, and a physical stimulus, light irradiation. Metalloselection takes place on addition of zinc cations which drive the amplification of Zn( 1A3C)2 by selection of the fittest constituent 1A3C. Photoselection is obtained on irradiation of the acylhydrazones that leads to photoisomerization from E-1A 1C to Z-1A1C configuration with amplification of the latter. These changes may be represented by square constitutional dynamic networks that display up-regulation of the pairs of agonists ( 1A2B, 2A1B), (Z-1A 1C, 2A2C), (1A3C, 2A1C), (Z-1A1C, 2A 3C) and the simultaneous down-regulation of the pairs of antagonists (1A1B, 2A2B), (1A 2C, 2A1C), (E-1A1C, 2A3C), (1A3C, 2A 1C). The orthogonal dual adaptation undergone by the set of acylhydrazones amounts to a network switching process. © 2014 American Chemical Society.

Zhang Z.,Jilin University | Yao D.,Jilin University | Zhou T.,Jilin University | Zhang H.,Jilin University | Wang Y.,Jilin University
Chemical Communications | Year: 2011

Crystalline samples of 3(5)-(9-anthryl)pyrazole and its one derivative exhibit interesting piezochromic behaviors with the emission colors differently changing from blue to green and from green to blue, respectively, upon grinding. © 2011 The Royal Society of Chemistry.

Zhu S.,Jilin University | Song Y.,Jilin University | Zhao X.,Jilin University | Shao J.,Jilin University | And 2 more authors.
Nano Research | Year: 2015

At present, the actual mechanism of the photoluminescence (PL) of fluorescent carbon dots (CDs) is still an open debate among researchers. Because of the variety of CDs, it is highly important to summarize the PL mechanism for these kinds of carbon materials; doing so can guide the development of effective synthesis routes and novel applications. This review will focus on the PL mechanism of CDs. Three types of fluorescent CDs were involved: graphene quantum dots (GQDs), carbon nanodots (CNDs), and polymer dots (PDs). Four reasonable PL mechanisms have been confirmed: the quantum confinement effect or conjugated π-domains, which are determined by the carbon core; the surface state, which is determined by hybridization of the carbon backbone and the connected chemical groups; the molecule state, which is determined solely by the fluorescent molecules connected on the surface or interior of the CDs; and the crosslink-enhanced emission (CEE) effect. To give a thorough summary, the category and synthesis routes, as well as the chemical/physical properties for the CDs, are briefly introduced in advance. © 2014, Tsinghua University Press and Springer-Verlag Berlin Heidelberg.

Gao Z.,Jilin University | Cheng G.,Jilin University | Shen F.,Jilin University | Zhang S.,Jilin University | And 3 more authors.
Laser and Photonics Reviews | Year: 2014

Highly efficient deep blue fluorescent material (SiPIM) based on phenanthro[9, 10-d]imidazole (PPI) and triphenylsilane is designed and synthesized. SiPIM presents a narrow deep blue emission, high quantum yield, high thermal stability and good morphological stability. A non-doped vacuum-deposited device using SiPIM as active layer achieves an extremely high external quantum efficiency of 6.29% with true deep blue CIE coordinates of (0.163, 0.040). The solution-processed device is also tried due to the good solubility of SiPIM, which displays a maximum ηext of 2.40% and CIE coordinates of (0.157, 0.041). © 2013 by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Adekola K.A.,Jilin University
Agricultural Engineering International: CIGR Journal | Year: 2015

In this study, two-dimensional flow simulation in food extruder die for intermeshing co-rotating twin-screw extruder were performed by solving Navier-Stokes equation and continuity equation for non-Newtonian fluid using finite element computer package of ANSYS/FLOTRAN. The objective of the study is to determine the nature of flow, heat and pressure distribution in the die and to determine the effect of screw speed on process parameters such as temperature, pressure and flow rate in the die. Four different die geometries were used. The levels of temperature considered were 120°C, 140°C, 160°C and 180°C. The screw speeds (taken as inlet velocity for the die) were 120, 160, 200 and 240 rpm. The results are presented for the flow profile, pressure distribution, temperature distribution and flow rate. For all the velocities considered, temperature has no significant effect on the velocity vector. The concentration of the vectors increase as the cross-sectional area becomes smaller. The vectors are relatively linear and smooth in the transition section of the die and get concentrated towards the die exit. The flow rate increases with increase in inlet velocity. Extruder throughput has a significant effect on the flow rate as reflected in higher flow rate recorded for increased throughput. The pressure at the die exit is lower than the highest pressure obtained for all the experimental runs. As the dough gets to the die exit, the dough experienced pressure drop. A pressure drop of more than 0.8MPa between the entrance and exit of the die was obtained. Experimental results obtained for the die geometries statistically correlate with the simulation results. © 2015, Int. Comm. of Agricultural and Biosystems Engineering. All rights reserved.

Tan L.-L.,Jilin University | Yang Y.-W.,Jilin University
Journal of Inclusion Phenomena and Macrocyclic Chemistry | Year: 2015

As a rapidly developing class of synthetic macrocycles with intrinsic characteristics and properties, pillarenes (or pillararenes) have become more and more attractive on account of their unique features and potentials in fabricating functional materials. This feature article provides an overview of molecular recognition and selfassembly of pillarenes. The host-guest motifs, building strategies, topological architectures, stimuli-responsiveness, functionalities and various supramolecular assemblies including mechanically interlocked molecules containing rotaxanes, polyrotaxanes and catenanes, self-inclusion complexes, supramolecular dimers and polymers, micelles, vesicles, tubes and artificial transmembrane channels are comprehensively discussed. Prospects about future research directions and applications in this research area are predicted. © Springer Science+Business Media Dordrecht 2014.

Wang B.,Jilin University | Yin Z.-D.,Jilin University | Bi L.-H.,Jilin University | Wu L.-X.,Jilin University
Chemical Communications | Year: 2010

We selected a Eu3+-containing tungstogermanate [(CH 3)4N]2.5H7.5[Eu(GeW 11O39)(H2O)2]2·4. 5H2O (EuGeW) as a molecular dyad combining fluorescence and electroactivity components within the same framework and studied its electroswitchable fluorescence in solution and in the thin-film, which can be reversibly switched by electrochemical stimulation. © 2010 The Royal Society of Chemistry.

Guo J.,Jilin University | Liu X.-S.,Jilin University | Chu S.-I.,University of Kansas
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2013

The nonsequential double ionization (NSDI) of Mg atoms is investigated in both linearly and circularly polarized laser fields with different kinds of potentials. The numerical results indicate that the "knee" structure still exists in circularly polarized laser fields in the 800-nm case with different potentials, which can be well explained by the corresponding momentum and position distribution of electrons. Moreover, the ionized electron energy of Mg atoms at the end of the pulse also shows that the behavior of rescattering electrons is different between linearly and circularly polarized cases. Besides, we also look into the angular distribution at the end of the pulse with different kind of potentials to illustrate the difference in the double-ionization mechanism between the linearly and circularly polarized cases. © 2013 American Physical Society.

Yu A.-Y.,Jilin University
Canadian Journal of Chemistry | Year: 2013

In this work, the reaction mechanism and kinetics of Cl + CH 2BrCH2Br → products are theoretically investigated for the first time. The optimized geometries and frequencies of all of the stationary points and selected points along the minimum-energy path for the three hydrogen abstraction channels and two bromine abstraction channels are calculated at the BH&H-LYP level with the 6-311G** basis set and the energy profiles are further calculated at the CCSD(T) level of theory. The rate constants are evaluated using the conventional transition-state theory, the canonical variational transition-state theory, and the canonical variational transition-state theory with a small-curvature tunneling correction over the temperature range 200-1000 K. The results show that reaction channel 3 is the primary channel and the calculated rate constants are in good agreement with available experimental values. The three-parameter Arrhenius expression for the total rate constants over 200-1000 K is provided. © 2013 Published by NRC Research Press.

Zhu Z.,Jilin University | Zhou X.,Jilin University | Luo D.,Jilin University | Liu Q.,Jilin University
Optics Express | Year: 2013

In this paper, a novel pseudo-random diamond turning (PRDT) method is proposed for the fabrication of freeform optics with scattering homogenization by means of actively eliminating the inherent periodicity of the residual tool marks. The strategy for accurately determining the spiral toolpath with pseudo-random vibration modulation is deliberately explained. Spatial geometric calculation method is employed to determine the toolpath in consideration of cutting tool geometries, and an iteration algorithm is further introduced to enhance the computation efficiency. Moreover, a novel two degree of freedom fast tool servo (2-DOF FTS) system with decoupled motions is developed to implement the PRDT method. Taking advantage of a novel surface topography generation algorithm, theoretical surfaces generated by using the calculated toolpaths are obtained, the accuracy of the toolpath generation and the efficiency of the PRDT method for breaking up the inherent periodicity of tool marks are examined. A series of preliminary cutting experiments are carried out to verify the efficiency of the proposed PRDT method, the experimental results obtained are in good agreement with the results obtained by numerical simulation. In addition, the results of scattering experiments indicate that the proposed PRDT method will be a very promising technique to achieve the scattering homogenization of machined surfaces with complicated shapes. © 2013 Optical Society of America.

Song N.,Jilin University | Yang Y.-W.,Jilin University
Chemical Society Reviews | Year: 2015

Nanotechnology has attracted much attention because it possesses many advantages to engineer new organized nanomaterials and endow them with improved performance. In recent decades, mesoporous silica nanoparticles (MSNs) have been proven to be excellent solid supports owing to their superior properties. Molecular and supramolecular switches have also received a lot of interest in the past decade on account of their unique features. Materials derived from the combination of MSNs as solid supports and molecular/supramolecular switches as movable entities have emerged in the literature and are playing prominent roles in materials science nowadays. Thus, in this review, we chose to gather significant and typical examples of intelligent materials, which comprise MSNs surface-immobilized with molecular and supramolecular switches, and overview their wide applications in many fields such as controlled release of cargo molecules for disease therapy and cell imaging. Utilizing the switching ability of molecular and supramolecular switches, smart hybrid nanomaterials are endowed with intelligently controllable properties in response to a variety of external stimuli such as pH variation, enzyme, light irradiation, temperature, redox, magnetic field, competition, and ultrasound. In order to rationalize the presentation concisely, we will introduce molecular switches and supramolecular switches cooperated with MSNs based on their different features and the actuations they are responsive for. © The Royal Society of Chemistry 2015.

Tong J.,CAS Changchun Institute of Applied Chemistry | Wu Z.,CAS Changchun Institute of Applied Chemistry | Li Y.,Jilin University | Wu D.,Jilin University
Dalton Transactions | Year: 2013

A series of polynuclear superalkali cations YLi3+ (Y = O2, CO4, C2O4, and C 2O6) have been studied using ab initio method. The structural characters and stabilities of these systems are found to be related to the nature of the central cores. In the lowest-energy structure of the C 2O4Li3+ cations, the central group features a slight distortion. While in the global minima of O2Li 3+, CO4Li3+ and C 2O6Li3+ cations, the central cores are divided into various units including one peroxo group (O2). These YLi3+ (Y = O2, CO4, C 2O4, and C2O6) species exhibit very low vertical electron affinities of 3.01-3.85 eV (except one outlier in one of the O2Li3+ species which lie much higher in energy than the most stable structure) and hence should be classified as superalkali cations, and the corresponding neutral species can be regarded as superalkalies. Such polynuclear superalkalies are candidates to the superatoms and offered potential building blocks for the assembly of new materials in which strong electron donors are involved. © 2013 The Royal Society of Chemistry.

Li Y.,Jilin University | Li L.,Jilin University | Sun J.,Jilin University
Angewandte Chemie - International Edition | Year: 2010

Heal thyself! Self-healing superhydrophobic coatings are fabricated by preserving healing agents of reacted fluoroalkylsilane in layered polymeric coatings that are porous and rigidly flexible. When the top layer of fluoroalkyl chains decomposes or the coatings are scratched, the healing agents migrate to the surface to restore the superhydrophobicity of the coatings (see picture). © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wu X.,Wuhan University | Wang X.,Jilin University | Zhang Y.,Wuhan University | Zhang Y.,Jilin University
ACS Applied Materials and Interfaces | Year: 2013

Nanoworm-like Li2FeSiO4-C composites are synthesized using triblock copolymer Pluronic P123 (poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide), EO20PO70EO20) as the structure directing agent (SDA) and under the effects of ethanol. As a polar nonaqueous cosolvent, ethanol has effects on the self-organization behavior of Pluronic P123 in water, which determines the final morphologies of the Li2FeSiO4-C composites synthesized. Li 2FeSiO4-C composite nanoparticles are obtained if no ethanol is added into the system during the synthesis process. When tested as lithium-ion battery cathodes, the Li2FeSiO4-C nanoworms show superior electrochemical performances. At the rate of 1 C (1 C = 166 mA g-1) the discharge capacity of the Li2FeSiO4-C nanoworms can reach 166 mAh g-1 in the voltage window of 1.5-4.8 V at room temperature. At the rates of 5, 10, and 20 C, the discharge capacities of the Li2FeSiO4-C nanoworms can stabilize at 120, 110, and 90 mAh g-1, respectively, and do not show obvious declines after hundreds of cycles. This performance of the Li2FeSiO4-C nanoworms at high rates is better than that of the Li2FeSiO 4-C nanoparticles synthesized and many other Li2FeSiO 4/C composites reported in the literature. The excellent electrochemical performances of the Li2FeSiO4-C nanoworms are believed to be related to the small sizes of the Li2FeSiO 4 nanocrystals inside the nanoworms and the carbon that coats and embeds the nanocrystals. © 2013 American Chemical Society.

Li M.,Jilin University | Gao C.,Jilin University | Hu H.,Jilin University | Zhao Z.,Jilin University
Carbon | Year: 2013

A simple method to prepare thermally reduced graphene oxide/polymer composites was developed to enhance the electrical conductivity of the polymer. Graphene oxide sheets were coated onto the surfaces of poly(vinylidene fluoride) powders and then hot pressed at 200 C to form composites with a segregated structure. After hot-pressing, the thermally reduced graphene oxide sheets were located in the interstices among the polymer domains and formed a two-dimensional conductive network. The resulting composites exhibited excellent electrical conductivity and a low percolation threshold (0.105 vol.%).

Zhu S.,Jilin University
Complex Analysis and Operator Theory | Year: 2014

An operator (formula presented.) on a complex Hilbert space (formula presented.) is called skew symmetric if (formula presented.) can be represented as a skew symmetric matrix relative to some orthonormal basis for (formula presented.). In this paper, we study the approximation of skew symmetric operators and provide a (formula presented.)-algebra approach to skew symmetric operators. We classify up to approximate unitary equivalence those skew symmetric operators (formula presented.) satisfying (formula presented.). This is used to characterize when a unilateral weighted shift with nonzero weights is approximately unitarily equivalent to a skew symmetric operator. © 2014, Springer Basel.

Li H.-L.,Jilin University | Xu H.-L.,Jilin University | Yang B.-S.,Jilin University | Chen Q.-D.,Jilin University | And 2 more authors.
Optics Letters | Year: 2013

Simultaneous monitoring of multiple combustion intermediates using femtosecond filament-induced nonlinear spectroscopy is demonstrated. Clean fluorescence emissions from free radicals CH, CN, NH, OH, and C2, as well as atomic C and H, are observed when a femtosecond filament is formed in the laminar ethanol/air flame on an alcohol burner. The fluorescence signals of these species are found to vary as functions of the position of interaction of the filament with the flame along the vertical axis of the central combusting flow, opening up a possibility for remote combustion diagnostic in engines by the excitation of femtosecond laser filament. © 2013 Optical Society of America.

Xia C.-L.,Jilin University | Liu X.-S.,Jilin University
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2013

We theoretically investigate the quantum paths of the high-order harmonic generation (HHG) by using a left and a right circularly polarized Gaussian laser pulse with a proper time delay. When the carrier phase of the two pulses is φ1=0, φ2=0.5π, the "gating" structure of the combined laser field disappears. The numerical results indicate that no "gating"-structure-combined laser pulse can control the quantum path. The HHG process is investigated by the semiclassical three-step model that makes use of a finite initial transverse velocity in the elliptically polarized field. For the case of λ1=800 nm, λ2=1600 nm, only a short quantum path contributes to the HHG, and an isolated attosecond pulse would be obtained. For the case of λ2=1600, φ2=0.5π, a supercontinuum spectrum plateau from 180 to 570 eV which includes the water window region is obtained, and attosecond pulses with the duration of about 75 as and a tunable central wavelength could be generated by superposing a bandwidth of 50 eV in the plateau area. © 2013 American Physical Society.

Tao J.-W.,Changchun University | Chang W.-X.,Jilin University
Proceedings - 2012 International Conference on Computer Science and Electronics Engineering, ICCSEE 2012 | Year: 2012

In the paper, the problem of MVDR beam former based on hyper complex processes is investigated in a scenarios where there exist one signal and one interference that are uncorrelated. First, a quaternion model of linear array with two-components EM vector-sensors is presented. Based on the quaternion model, a quaternion MVDR (QMVDR) beam former is derived. The quaternion-valued output y(n) of the QMVDR consists of two complex components y 1(n) and y 2(n). In y 2(n), there exist only the interference and noise components, but no desired signal. The desired signal is included in y 1(n) and it is corrupted by the interference and noise. To extract the desired signal, we can employ y 2(n) to cancel partly the interference component in y 1(n). Thus, an interference and noise cancellation (INC) algorithm of QMVDR is proposed. The INC algorithm of QMVDR beam former is similar to the generalized side lobe canceller. Simulation results show that the proposed algorithm can achieve a much better performance in terms of output SINR than existing ones. © 2012 IEEE.

Li J.-L.,Lund University | Li J.-L.,Jilin University | Mata R.A.,University of Gottingen | Ryde U.,Lund University
Journal of Chemical Theory and Computation | Year: 2013

The oxygen-atom transfer reaction catalyzed by the mononuclear molybdenum enzyme dimethyl sulfoxide reductase (DMSOR) has attracted considerable attention through both experimental and theoretical studies. We show here that this reaction is more sensitive to details of quantum mechanical calculations than what has previously been appreciated. Basis sets of at least triple-ζ quality are needed to obtain qualitatively correct results. Dispersion has an appreciable effect on the reaction, in particular the binding of the substrate or the dissociation of the product (up to 34 kJ/mol). Polar and nonpolar solvation effects are also significant, especially if the enzyme can avoid cavitation effects by using a preformed active-site cavity. Relativistic effects are considerable (up to 22 kJ/mol), but they are reasonably well treated by a relativistic effective core potential. Various density-functional methods give widely different results for the activation and reaction energy (differences of over 100 kJ/mol), mainly reflecting the amount of exact exchange in the functional, owing to the oxidation of Mo from +IV to +VI. By calibration toward local CCSD(T0) calculations, we show that none of eight tested functionals (TPSS, BP86, BLYP, B97-D, TPSSH, B3LYP, PBE0, and BHLYP) give accurate energies for all states in the reaction. Instead, B3LYP gives the best activation barrier, whereas pure functionals give more accurate energies for the other states. Our best results indicate that the enzyme follows a two-step associative reaction mechanism with an overall activation enthalpy of 63 kJ/mol, which is in excellent agreement with the experimental results. © 2013 American Chemical Society.

Qin W.,Jilin University | Zhang D.,Jilin University | Zhang D.,Beihua University | Zhao D.,Jilin University | And 2 more authors.
Chemical Communications | Year: 2010

We report the novel near-infrared (NIR) photocatalysis of YF 3:Yb3+,Tm3+/TiO2 core/shell nanoparticles. The core/shell nanoparticles show photocatalytic activity under the NIR irradiation. This study demonstrates that the NIR energy can be used as the driving source for photocatalysis besides the UV and visible energy. © 2010 The Royal Society of Chemistry.

Zhang G.,Jilin University | Zhao L.,Jilin University
Dalton Transactions | Year: 2013

Novel nickel hierarchical structures were prepared through a facile one-pot solvothermal approach in the presence of surfactant and mineralizer. The influence of dynamics factors such as polyvinylpyrrolidone (PVP) content, ratio (R) between NaF and NH3·H2O on the morphologies of the as-synthesized products were investigated in detail. By regulating the dynamics factors, nickel crystals with three different structures (hcp and fcc mixture structure, fcc structure and a mostly hcp structure) were synthesized. Meanwhile, the corresponding morphologies are changed from hierarchical structures composed of nanoparticles to hierarchical structures consisted of nanoflakes, and to polyhedra. The values of saturation magnetizations of nickel crystals also range from 41.6 to 8 emu g-1 because of the change of crystal structure from fcc to mostly hcp. One thing to be mentioned is that the mostly hcp phase can be completely converted into fcc phase if the solvothermal treatment temperature is further enhanced to 220 °C. Further, the Congo red (CR) removal ability by the as-obtained nickel particles was evaluated. By the investigation of adsorption and desorption experiments on nickel powders, we can ascertain that chemical reduction and physical adsorption happen at the same time during the treatment process of CR solution. This journal is © 2013 The Royal Society of Chemistry.

Du P.,Northeast Normal University | Yang Y.,Northeast Normal University | Yang J.,Northeast Normal University | Liu B.-K.,Jilin University | Ma J.-F.,Northeast Normal University
Dalton Transactions | Year: 2013

Four novel metal-organic frameworks (MOFs) based on high-nuclear metal carboxylate clusters, namely, [Zn4(L)2(μ3- OH)2(H2O)1.5]·2H2O (1), [Zn5Na(L)2(μ3-OH)4(CH 3CH2O)(H2O)2] (2), [Cd 4(L)2(BIME)0.5(μ3-OH) 2(H2O)1.5]·2H2O (3), and [Zn4(L)2(BET)0.5(μ3-OH) 2(H2O)] (4), where H3L = (3,5-dicarboxyl- phenyl)-(4-(2′-carboxyl-phenyl)-benzyl)ether, BET = 1,1′-(2′- oxybis(ethane-2,1-diyl))bis(1,2,4-triazol-1-yl), BIME = 1,2-bis(imidazol-1-yl) ethane, have been synthesized under hydrothermal conditions. In 1, each planar octanuclear zinc cluster [Zn8(μ3-OH) 8(CO2)12(H2O)3] is linked by twelve L anions to give an unusual (3,12)-connected framework with (4 3)2(420·628·8 18) topology. In 2, dodecanuclear heterometallic clusters [Zn 10Na2(μ3-OH)8(CO 2)12(CH3CH2O)2(H 2O)4] are surrounded by twelve L anions to form a (3,12)-connected net with the same topology as 1. However, 3 exhibits a rare (3,14)-connected (43)(324)(34·4 20·514·634·7 11·88) net based on octanuclear cadmium cluster [Cd8(BIME)2(μ3-OH)4(CO 2)12(H2O)4]·2H2O as a 14-connected node and H3L as a 3-connected node. In 4, each octanuclear zinc cluster [Zn8(BET)2(μ3-OH) 4(CO2)12(H2O)2] is linked by twelve L anions to furnish a (3,14)-connected net with the same topology as 3. The optical energy gaps and photoluminescence were investigated for the compounds. Moreover, compounds 1-4 exhibit good photocatalytic activities for degradation of methylene blue (MB) under UV irradiation and show good stability towards UV photocatalysis. In addition, 1 and 4 display a photocurrent density under several on-off cycles of illumination. © The Royal Society of Chemistry 2013.

Ma R.,Washington State University | Xu Y.,Jilin University | Zhang X.,Washington State University
ChemSusChem | Year: 2015

(Figure Presented). Transforming plant biomass to biofuel is one of the few solutions that can truly sustain mankind's long-term needs for liquid transportation fuel with minimized environmental impact. However, despite decades of effort, commercial development of biomass-to-biofuel conversion processes is still not an economically viable proposition. Identifying value-added co-products along with the production of biofuel provides a key solution to overcoming this economic barrier. Lignin is the second most abundant component next to cellulose in almost all plant biomass; the emerging biomass refinery industry will inevitably generate an enormous amount of lignin. Development of selective biorefinery lignin-to-bioproducts conversion processes will play a pivotal role in significantly improving the economic feasibility and sustainability of biofuel production from renewable biomass. The urgency and importance of this endeavor has been increasingly recognized in the last few years. This paper reviews state-of-the-art oxidative lignin depolymerization chemistries employed in the papermaking process and oxidative catalysts that can be applied to biorefinery lignin to produce platform chemicals including phenolic compounds, dicarboxylic acids, and quinones in high selectivity and yield. The potential synergies of integrating new catalysts with commercial delignification chemistries are discussed. We hope the information will build on the existing body of knowledge to provide new insights towards developing practical and commercially viable lignin conversion technologies, enabling sustainable biofuel production from lignocellulosic biomass to be competitive with fossil fuel. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA.

Yuan J.,Jilin University | Li H.,Jilin University | Gao S.,Jilin University | Lin Y.,Jilin University
Chemical Communications | Year: 2010

Anatase TiO2 nanotube (TiNT) arrays have been fabricated on a p-type boron-doped diamond substrate by a liquid phase deposition method using a ZnO nanorod template. The n-type TiNT/p-type diamond heterojunction structures which are realized show significantly enhanced photocatalytic activities with good recyclable behavior, with respect to the cases of sole TiNTs. © The Royal Society of Chemistry 2010.

Xie Y.,Jilin University | Xie Y.,State University of New York at Stony Brook | Oganov A.R.,State University of New York at Stony Brook | Oganov A.R.,Moscow State University | Ma Y.,Jilin University
Physical Review Letters | Year: 2010

Using evolutionary methodology for crystal structure prediction, we explore high-pressure phases of CaLi2, a compound made of two elements that show anomalies upon compression. In addition to the known low-pressure Laves phases, we find two novel structures with space groups C2/c and P21/c, stable at pressure ranges of 35-54 GPa and 54-105 GPa, respectively. It is found that decomposition into pure elements is energetically favorable at pressures of 20-35 GPa and above 105 GPa. Such decomposition-recombination-decomposition oscillating behavior with pressure is predicted for the first time in a binary compound. The C2/c and P21/c phases are predicted to be superconductors, and the calculated Tc of ∼15K at 45 GPa is in good agreement with experiment. © 2010 The American Physical Society.

Gold nanoparticles are extensively investigated for their potential biomedical applications. Therefore, it is pertinent to thoroughly evaluate their biological effects at different levels and their underlying molecular mechanism. Frequently, there are discrepancies about the biological effects of various gold nanoparticles among the reports dealing with different models. Most of the studies focused on the different biological effects of various nano-properties of the nanomaterials. We hypothesize that the biological models with different metabolic processes would be taken into account to explain the observed discrepancies of biological effects of nanomaterials. Herein, by using mouse embryo fibroblast cell line (MEF-1) and human embryonal lung fibroblast cell line (MRC-5) as in vitro models, we studied the cellular effects of gold nanorods (AuNRs) coated with poly (diallyldimethyl ammonium chloride) (PDDAC), polyethylene glycol and polystyrene sulfonae (PSS). We found that all three AuNRs had no effects on cellular viability at the concentration of 1 nM; however, AuNRs that coated with PDDAC and PSS induced significant up-regulation of heme oxygenase-1 (HO-1) which was believed to be involved in cellular defense activities in MEF-1 but not in MRC-5 cells. Further study showed that the low fundamental expression of transcription factor Bach-1, the major regulator of HO-1 expression, in MEF-1 was responsible for the up-regulation of HO-1 induced by the AuNRs. Our results indicate that although AuNRs we used are non-cytotoxic, they cell-specifically induce change of gene expression, such as HO-1. Our current study provides a good example to explain the molecular mechanisms of differential biological effects of nanomaterials in different cellular models. This finding raises a concern on evaluation of cellular effects of nanoparticles where the cell models should be critically considered.

Jin R.,CAS Changchun Institute of Applied Chemistry | Bian Z.,CAS Changchun Institute of Applied Chemistry | Li J.,Jilin University | Ding M.,CAS Changchun Institute of Applied Chemistry | Gao L.,CAS Changchun Institute of Applied Chemistry
Dalton Transactions | Year: 2013

ZIF-8 crystal coatings were prepared by direct growth on different flexible polyimide substrates including a thin membrane and electrospun nanofiber mat. In SEM pictures, the ZIF-8 crystals exhibit a rhombic dodecahedron morphology. Owing to the flexible polyimide substrate, the MOF-polymer film may be moderately bent or easily tailored when not destroyed. The ZIF-8 coatings can be activated at high temperature owing to the excellent thermal resistance and low coefficient of thermal expansion of the polyimide. Furthermore, this material may be used as an efficient heterogeneous catalyst for the Knoevenagel reaction and can be easily recovered. The ZIF-8 coatings and 2-methylimidazole show similar catalytic behaviour as a weak base. This journal is © 2013 The Royal Society of Chemistry.

Ma Y.-L.,Jilin University | Harada M.,Nagoya University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2016

The spectroscopy of the doubly heavy baryons including different heavy quarks is studied based on the heavy quark symmetry of QCD. We point out that, when the two heavy quarks are in S-wave, these baryons with a certain spin jl of the light cloud can be classified into two sets: a heavy quark singlet with total spin of j=jl and a heavy quark multiplet with j=(jl+1), jl,.|jl-1|, all the baryons in these two sets have the same mass and, the baryons with the same quantum numbers in these two sets do not mix with each other. We finally point out that the strong decay of the first excited baryon with light spin jl=1/2 to the ground state and one-pion is determined by the mass splitting through the generalized Goldberger-Treiman relation. © 2016 The Authors.

Sun Q.,Jilin University | Wang N.,Jilin University | Xi D.,Jilin University | Yang M.,CAS Dalian Institute of Chemical Physics | Yu J.,Jilin University
Chemical Communications | Year: 2014

Using an organosilane surfactant as the mesopore director, hierarchical porous silicoaluminophosphate SAPO-34 is obtained as an assembly of nanocrystallites intergrown into cubic micrometer-sized crystals, which show excellent performance in MTO reactions with a remarkably prolonged catalyst lifetime and enhanced selectivity of ethylene and propylene compared to the conventional microporous SAPO-34. This journal is © the Partner Organisations 2014.

Lu C.,Jilin University | Ben T.,Jilin University | Xu S.,Jilin University | Qiu S.,Jilin University
Angewandte Chemie - International Edition | Year: 2014

A new approach to preparing 3D microporous conductive polymer has been demonstrated in the electrochemical synthesis of a porous polyaniline network with the utilization of a MOF thin film supported on a conducting substrate. The prepared porous polyaniline with well-defined uniform micropores of 0.84 nm exhibits a high BET surface area of 986 m2g-1 and a high electric conductivity of 0.125 Scm-1 when doped with I2, which is superior to existing porous conducting materials of porous MOFs, CMPs, and COFs. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hu Z.,University of Maryland University College | Hu Z.,Jilin University | Weeks J.D.,University of Maryland University College
Physical Review Letters | Year: 2010

We use a new configuration-based version of linear response theory to efficiently solve self-consistent mean field equations relating an effective single particle potential to the induced density. The versatility and accuracy of the method is illustrated by applications to dewetting of a hard sphere solute in a Lennard-Jones fluid, the interplay between local hydrogen bond structure and electrostatics for water confined between two hydrophobic walls, and to ion pairing in ionic solutions. Simulation time has been reduced by more than an order of magnitude over previous methods. ©2010 The American Physical Society.

Li H.,University of Waterloo | Li H.,Jilin University | Le Roy R.J.,University of Waterloo | Roy P.-N.,University of Waterloo | McKellar A.R.W.,NRC Steacie Institute for Molecular Sciences
Physical Review Letters | Year: 2010

Clusters of para-hydrogen (pH2) have been predicted to exhibit superfluid behavior, but direct observation of this phenomenon has been elusive. Combining experiments and theoretical simulations, we have determined the size evolution of the superfluid response of pH2 clusters doped with carbon dioxide (CO2). Reduction of the effective inertia is observed when the dopant is surrounded by the pH2 solvent. This marks the onset of molecular superfluidity in pH2. The fractional occupation of solvation rings around CO2 correlates with enhanced superfluid response for certain cluster sizes. © 2010 The American Physical Society.

Song H.-W.,Jilin University
Faguang Xuebao/Chinese Journal of Luminescence | Year: 2013

The birth of the concept of photonic crystal (PC) makes the dream of manipulating photon become reality. Possessing spatial periodicity in their dielectric constant on the length scale of the optical wavelength, PCs behave with electromagnetic waves just like atomic crystals do with electrons. As an electronic band gap is created by the periodic arrangement of atoms in a semiconductor, the periodic electromagnetic modulation created by a PC can yield a photonic stop band (PSB), which has significant modification on the spontaneous radiative rate and emission intensity of the fluorescent guest implanted in the PCs. The modification of PCs on spontaneous emission is attracting current interests due to its considerable scientific and technological values. In this article, after highlight the international development on this field, on emphasis, we will introduce our recent results on the preparation of three-dimensional lanthanide oxide PCs through the self-assembly method and the modification of PCs on spontaneous emission of rare earth ions. Recently, we observed a number of interesting phenomena, such as the observation of Lamb shift, inhibited long-scale energy transfer (ET) and improvement of luminescent quantum yield in lanthanide oxide inverse opal PCs.

Zhang Y.,Jilin University | Jiang S.,Jilin University
Organic and Biomolecular Chemistry | Year: 2012

A new and easy-to-prepare gelator based on cyano-substituted amide (BPNIA) was designed and synthesized. BPNIA could form thermoreversible gel in DMSO-H2O (v/v, 9:1) and ultrasound-stimulated gel in DMSO. FT-IR, UV-vis and XRD spectra indicated that the gelator molecules self-assemble into a fibrous network resulting from the cooperation of intermolecular hydrogen bonding, π-π stacking and cyano interactions. BPNIA can act as a highly selective colorimetric sensor for fluoride in DMSO, overcoming the interference of H2PO4 -, AcO- and other halide anions. The deprotonation of the NH groups is responsible for the dramatic color change from colorless to yellow. Interestingly, the organogel of BPNIA could allow a two channel fluoride response by proton controlled reversible sol-gel transition and color changes. © 2012 The Royal Society of Chemistry.

Li Y.,Jilin University | Ma Y.,Jilin University
Solid State Communications | Year: 2010

Using ab initio evolutionary methodology for crystal structure prediction, we have found two orthorhombic structures of P m n 2 1 and C m c 2 1 for potential superhard OsN, energetically much superior to the previously proposed NaCl-type and WC-type structures. The P m n 2 1 structure which consisted of distorted OsN 4 tetrahedra is stable up to 62 GPa, above which C m c 2 1 becomes energetically more favorable. The C m c 2 1 structure contains the Os-Os and Os-N-N chains and possesses the unique diatomic N-N bond. OsN within two orthorhombic phases is found to be an ultra-incompressible material due to the high bulk modulus (∼350 GPa), which originates from the strong and directional covalent bonds in two structures. Analysis of the calculated formation energy suggested that the two structures could be synthesized at moderate pressures of ∼20 GPa. © 2010 Elsevier Ltd. All rights reserved.

Wang L.,Jilin University | Deng J.,Jilin University | Lou Z.,Jilin University | Zhang T.,Jilin University
Journal of Materials Chemistry A | Year: 2014

Quasi-1D nanofibers with heterostructure were prepared via a simple two-step process called the electrospinning technique and hydrothermal process. The nanostructures exhibit the unique feature of TiO2 nanofibers (250 nm) kept inside and well-structured Co3O4 octahedral nanoparticles loading outside. The cross-linked Co3O 4/TiO2 nanostructures exhibit intriguing morphologies, architectures and chemical compositions. As a potential sensing material in chemosensor applications, the quasi-1D heterostructure nanofibers exhibit a relatively high catalysis response to CO, and good CO-sensing performance even exposure to a humid environment. 2014 This journal is © the Partner Organisations.

Liu Q.-C.,CAS Changchun Institute of Applied Chemistry | Liu Q.-C.,Jilin University | Xu J.-J.,CAS Changchun Institute of Applied Chemistry | Chang Z.-W.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Journal of Materials Chemistry A | Year: 2014

Cobalt oxide nanosheets (Co3O4 NSs) are grown on carbon paper (CP) by an efficient and facile electrodeposition method. When directly used as free-standing cathode for lithium-oxygen batteries, the Co 3O4 NSs/CP is found to be robust and shows enhanced specific capacity and cycling stability. This journal is © the Partner Organisations 2014.

Wu X.,Zhejiang University | Tong X.,Zhejiang University | Wu Q.,Zhejiang University | Ding H.,Jilin University | Yan W.,Jilin University
Journal of Materials Chemistry A | Year: 2014

Reversible phase transformation-type electrolyte, consisting of 1-(3-sulfonic group)propyl-3-methyl imidazolium cation (MIMPS) and tungstovanadophosphoric anion with Keggin structure, [MIMPS]4PW 11VO40, is synthesized and characterized using elemental analysis, IR, UV, XRD, and TG-DTA. This product is in quasi-solid-state, a novel type of ionic liquid, with a layered type of structure. This compound can process the phase transition from a crystal phase to an isotropic phase below 100°C. Moreover, the DTA and conductivity-temperature plot shows an observable increase in conductivity above 84.2°C, which is caused by the phase transformation from crystal phase to isotropic phase. This novel electrolyte material exhibits high conductivity (8.60 × 10-2 S cm-1 at 83°C and 80% relative humidity). In the range of the measured temperature, its conductivity increases with higher temperature, indicating that the conductive activation energy for this conduction step is 42.06 kJ mol-1. © the Partner Organisations 2014.

Lu X.,Aalto University | Lu X.,Jilin University | Lu T.,Aalto University | Kibert C.J.,University of Florida | Viljanen M.,Aalto University
Applied Energy | Year: 2014

This paper presents a new methodology for modeling building energy performance that addresses some important limitations of building simulation. This new methodology develops a physical model for accurately predicting indoor environmental conditions and energy consumption by selecting best match parameters and variables. The innovative aspect of the proposed methodology is the introduction of open and closed loop system approaches to dynamically model the complex interaction of factors that contribute to building thermal performance and their uncertainties. This allows simultaneous tracking of both the lead and lag times between heating excitations and indoor thermal responses to account for their mutually excitatory interaction. The model system is solved using a Laplace transform technique, with an explicit solution that includes physical and generalized parameters calibrated by measurements. Singular value decomposition techniques are applied to further determine the model variables for the best approximation using lower dimensions. As a result the model complexity and the model parameters and variables are minimized while still preserving the physical meaning of the model. A careful, detailed validation and assessment of the model performance is conducted using a case study of a dance hall at a swim center (R2>0.9). A further validation of the model is also undertaken by assessing its forecasting capability against benchmark persistence models. The proposed model outperforms the benchmarks especially over longer time horizons. The methodology is useful in developing a minimal but comprehensive and accurate energy performance physical model which can reliably capture the dynamics of building thermal and energy performance. The proposed method can serve the needs of prediction and control applications in a wide variety of building types and can be incorporated into the most commonly used simulation models. © 2013 Elsevier Ltd.

Wu B.,Jilin University
Archive of Applied Mechanics | Year: 2014

The half-power bandwidth method is commonly used to evaluate the system damping by using frequency response curves and assuming a small damping ratio. Preceding derivations obtain the third-order corrections to the classical formula but still show large errors when the damping ratio is high, especially for the acceleration case. In this note, new approximate formulas for damping ratio in terms of the half-power bandwidth are established using displacement and acceleration frequency response functions, respectively. The proposed formulas, third-order correction and classical approximations are compared by using relative errors of calculated damping ratios for both displacement and acceleration cases. The new formulas for damping ratio are brief and show excellent accuracy for small as well as high damping ratios. © 2014, Springer-Verlag Berlin Heidelberg.

Comotti A.,University of Milan Bicocca | Bracco S.,University of Milan Bicocca | Ben T.,Jilin University | Qiu S.,Jilin University | Sozzani P.,University of Milan Bicocca
Angewandte Chemie - International Edition | Year: 2014

Porous organic frameworks perform a variety of functions, owing to their extremely large surface areas, but the dynamics of the structural elements have never been explored. Our discovery of ultra-fast molecular rotors (10 6 Hz at 225 K) in their architectures allows us to look at them from a new perspective. The constructive elements are robust struts and rapid rotors, resulting in a dynamic material whose motion can be frozen or released at will. The rotational motion can be actively regulated in response to guests. As the temperature is increased, the rotors spin ever faster, approaching free-rotational diffusion at 550 K. The unusual combination of remarkable nanoporosity with fast dynamics is intriguing for engineering oscillating dipoles and producing responsive materials with switchable ferroelectricity, and for applications spanning from sensors to actuators, which capture and release chemicals on command. Fast molecular dynamics and large sorption capacity were combined in porous organic frameworks. The low-density, yet robust covalent architectures sustain extremely rapid rotational motion of the phenylene rings up to high temperatures. Porosity enables modulation of rotor dynamics by chemical stimuli: linear alkanes and iodine vapors, pervading the material, regulate rotor speed at will. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wang L.,Jilin University | Zhang H.,Jilin University
Journal of Physical Chemistry C | Year: 2011

The electronic and charge transport properties of a series of methylchalcogeno-substituted acene derivatives are investigated via quantum chemical calculations. To gain a better understanding of the role of methylchalcogeno substitution, the results for bis(methylchalcogeno)anthracene and bis(methylthio)pentacene are compared with those for their parent oligoacenes, that is, anthracene and pentacene. The introduction of methylchalcogeno group can increase the stability of their anionic compounds and lower the injection barriers of electrons in organic electronics devices. The methylchalcogeno group also change the charge transport properties by enhancing π stacking and chalcogen-chalcogen interactions. The calculations predict that the electron mobilities of bis(methylthio)anthracene and bis(methyltelluro)anthracene are 0.68 and 0.48 cm2/(V•s), respectively, which increase by a factor of 2 to 3 with respect to that of anthracene. © 2011 American Chemical Society.

Chen X.,Jilin University | Wang Z.,Jilin University | Ma Y.,Jilin University
Journal of Physical Chemistry C | Year: 2011

We present predictions of thermoelectric figure of merit (ZT) on Si/Ge superlattice nanowires (SLNWs) based on ab initio electronic structure calculations and Boltzmann transport theory. Our results suggest that Si/Ge SLNW is a promising candidate for thermoelectric applications, much better than the known Si nanowires. We find that a ZT value higher than 1 at 300 K is achievable for 1.7 nm diameter Si/Ge SLNW in case of a 3-order reduction on lattice thermal conductivity with respect to bulk Si. The high thermoelectric performance in Si/Ge SLNWs can be further improved by tailoring the electrical transport (S2σ), which strongly depends on their unique electronic structures. We also discuss how the structural properties such as nanowire diameter, superlattice period, constituent length ratio, and the chemical potential (or doping levels) can be tuned to derive an optimal ZT for Si/Ge SLNWs. © 2011 American Chemical Society.

Jiang P.,Jilin University | Yue Y.,Jilin University
Experimental and Therapeutic Medicine | Year: 2013

The aim of this study was to review the literature and identify the association between human papillomavirus (HPV) oncoproteins and apoptosis. HPV-associated apoptosis may be primarily blocked by a number of oncoproteins, including E5, E6 and E7. E5 protein protects cells from tumor necrosis factor-associated apoptosis; the oncoprotein E6 predominantly inhibits apoptosis through the p53 pathway; and oncoprotein E7 is involved in apoptosis activation and inhibition. In addition, HPV oncoproteins are involved in activating or repressing the transcription of E6/E7. In conclusion, HPV oncoproteins, including E5, E6 and E7 protein, may interfere with apoptosis via certain regulatory principles.

Jia B.,Jilin University | Cheong G.-W.,Gyeongsang National University | Zhang S.,Jilin University
Extremophiles | Year: 2013

Enzymes from many archaea colonizing extreme environments are of great interest because of their potential for various biotechnological processes and scientific value of evolution. Many enzymes from archaea have been reported to catalyze promiscuous reactions or moonlight in different functions. Here, we summarize known archaeal enzymes of both groups that include different kinds of proteins. Knowledge of their biochemical properties and three-dimensional structures has proved invaluable in understanding mechanism, application, and evolutionary implications of this manifestation. In addition, the review also summarizes the methods to unravel the extra function which almost was discovered serendipitously. The study of these amazing enzymes will provide clues to optimize protein engineering applications and how enzymes might have evolved on Earth. © 2012 Springer Japan.

Wang Y.,Kunming Medical University | Ge P.,Jilin University | Zhu Y.,Kunming Medical University
Mediators of Inflammation | Year: 2013

Brain injury caused by cerebral ischemia/reperfusion is a complicated pathophysiological course, in which inflammation is thought to play an important role. Toll-like receptors are a type of transmembrane proteins, which can recognize either exogenous pathogen-associated molecular patterns or endogenous stress or damage-associated molecular patterns in the innate immune system and initiate inflammatory responses. Among Toll-like receptors, TLR2 and TLR4 are found to be more important than others in the pathological progression of cerebral injury due to ischemia and reperfusion. This review will focus on the biological characteristics and functions of TLR2 and TLR4 and their downstream signal pathways. © 2013 Ying Wang et al.

Liu X.,Jilin University
Zhonghua lao dong wei sheng zhi ye bing za zhi = Zhonghua laodong weisheng zhiyebing zazhi = Chinese journal of industrial hygiene and occupational diseases | Year: 2013

To examine the effect of exposure to extremely low-frequency electromagnetic fields (ELF EMFs) on the liver function of workers. The workers in a factory were selected as subjects, and the recent physical examination data of these workers were collected. The workers aged 20∼40 years and with more than 2 years' working experience were included for analysis; considering the intensity of electromagnetic field, the workers exposed to less electromagnetic radiation were assigned to exposure I group (n = 123), those exposed to more electromagnetic radiation to exposure II group (n = 229), and those not exposed to electromagnetic radiation to control group (n = 212). There were no significant differences in sex, age, height, and body weight between the three groups (P > 0.05). Physical examination, including measurements of direct bilirubin (DBil), alanine aminotransferase (ALT), alkaline phosphatase (ALP), aspartate aminotransferase (AST), γ-glutamyl transpeptidase (GGT), and albumin, was performed in a health examination center. The intensity of electromagnetic field was measured by EFA-300 power frequency electromagnetic field analyzer, and the intensity of noise by AWA5610D integrating sound level meter. The intensities of electric field and the magnetic field in exposure II group were significantly higher than those in the exposure I group. The levels of ALT, ALP, AST, GGT and albumin in exposure II group were significantly higher than those in exposure I group and control group. However, the level of direct bilirubin in exposure II group was significantly lower than that in exposure I group and control group. Occupational exposure to ELF EMFs may affect human liver function.

Zhang P.,Jilin University | Lian J.S.,Jilin University | Jiang Q.,Jilin University
Physical Chemistry Chemical Physics | Year: 2012

Nitrogen-doped carbon nanotubes (NCNTs) are attractive for electrocatalytic applications in fuel cells due to their low cost and high electrocatalytic activity. By using density functional theory calculations, the electrocatalytic mechanisms of the oxygen reduction reaction (ORR) under electrochemical conditions are studied at graphite-like N groups (N G) and pyridine-like N groups (N P) of NCNTs, in which the effect of electrode potentials on the activation energy (E a) and reaction energy (E r) is taken into account. The ORR occurs at both N G and N P defect sites via two different four-electron OOH and two-electron H 2O 2 mechanisms. At the lower potential region, both mechanisms are simultaneously responsible for the reaction at N G and N P defect sites; while at higher potentials, the four-electron mechanism becomes dominant and the ORR at N P defect sites is more energetically favorable than that at N G defect sites. © 2012 the Owner Societies.

Zheng W.-T.,Jilin University | Sun C.Q.,Nanyang Technological University | Sun C.Q.,Xiangtan University
Energy and Environmental Science | Year: 2011

As a new class of materials, carbon nanotubes (CNTs) and graphene nanoribbons (GNRs) have been continuing fascinating the community with properties that can be seen from neither bulk graphite nor diamond. Although the physics and chemistry of these carbon allotropes have been intensively investigated from various perspectives, the laws governing the fascinations and their interdependence remain as yet undetermined. From the perspectives of bond and nonbond formation, dissociation, relaxation, vibration, and the associated energetics and dynamics of charge repopulation, polarization, densification, and localization, this article aims to show that the broken-bond-induced local bond contraction and bond strength gain, quantum entrapment and densification of charge and energy, polarization of the unpaired edge dangling σ-bond electrons, and the formation of the pseudo-π-bond between the dangling σ-bond electrons along the edges are responsible for the anomalies. Theoretical reproduction of the experimentally observed elastic modulus enhancement, melting point depression, layer-number, strain, pressure and temperature induced Raman shift, C 1s core-level positive shift, work function reduction, band gap expansion, edge and defect selective generation of the Dirac-Fermi polarons and the associated magnetism consistently confirmed that the shorter and stronger bonds between undercoordinated carbon atoms modulate locally the atomic cohesive energy, the Hamiltonian, and hence the detectable bulk properties. The polarization of the unpaired dangling σ-bond electrons by the densely, deeply, and locally entrapped core and bonding electrons generates the massless, magnetic and mobile Dirac-Fermi polarons at sites surrounding vacancies and zigzag-GNR edges. The pseudo-π-bond formation between the nearest dangling σ-bond electrons along the armchair-GNR and the reconstructed zigzag-GNR edges discriminates them from the zigzag-GNR edges or vacancies in the electronic and magnetic properties. Consistency between predictions and observations confirmed that the C-C bond contracts by up to 30% with a 152% bond strength gain at the edges with respect to those in the bulk diamond. © 2011 The Royal Society of Chemistry.

Sun L.,Jilin University | Bai F.-Q.,Jilin University | Zhao Z.-X.,Jilin University | Zhang H.-X.,Jilin University
Solar Energy Materials and Solar Cells | Year: 2011

The novel linear and star molecules based on benzothiadiazole as a central core, TPA as end groups and different functional groups as π-spacers were theoretically examined in the OSC applications. The geometry structures in ground and excited state, ionization potentials (IPs), electron affinities (EAs) and reorganization energy (Eλ and Eλ -) of linear and star molecules were studied by DFT methods. The absorption and the emission spectra were calculated by TD-BHandHLYP method. Star molecules based on ethynyl groups as π-spacer exhibit ameliorative IPs, EAs, Eλ and Eλ -, indicating they are more suitable for the formation and transfer of holes than the others. Moreover, the diethynyl groups improve the charge transfer character and extend the absorption wavelength towards the range with the maximum photon flux. © 2011 Elsevier B.V. All rights reserved.

Zhu G.,Jilin University
Lecture Notes in Electrical Engineering | Year: 2016

A new algorithm about global fast Fourier transform (FFT) is introduced in this paper, which is more reasonable and scientific than old FFT. The algorithm of FFT is more reasonable and more scientific than in the past. Experiments indicate that this algorithm can detect oil storehouses fast and exactly. Furthermore, the relation between template scale feature and oil depot recognition is indicated, i.e., the algorithm speed is increased faster than direct convolution along with the template scale increasing, and small template can detect large oil storehouses, not vice versa. The precision of the detection will rise along with template scale reducing, but at the same time the false alert will appear. Meanwhile, the problem of this algorithm is pointed and will be solved in the further research. © Springer-Verlag Berlin Heidelberg 2016.

Wang Y.-L.,Jilin University | Wang Y.-L.,University of Stockholm | Lu Z.-Y.,Jilin University | Laaksonen A.,University of Stockholm
Physical Chemistry Chemical Physics | Year: 2012

Dissipative particle dynamics simulations are used to study the specific binding structures of polyamidoamine (PAMAM) dendrimers on amphiphilic membranes and the permeation mechanisms. Mutually consistent coarse-grained (CG) models both for PAMAM dendrimers and for dimyristoylphosphatidylcholine (DMPC) lipid molecules are constructed. The PAMAM CG model describes correctly the conformational behavior of the dendrimers, and the DMPC CG model can properly give the surface tension of the amphiphilic membrane. A series of systematic simulations is performed to investigate the binding structures of the dendrimers on membranes with varied length of the hydrophobic tails of amphiphiles. The permeability of dendrimers across membranes is enhanced upon increasing the dendrimer size (generation). The length of the hydrophobic tails of amphiphiles in turn affects the dendrimer conformation, as well as the binding structure of the dendrimer-membrane complexes. The negative curvature of the membrane formed in the dendrimer-membrane complexes is related to dendrimer concentration. Higher dendrimer concentration together with increased dendrimer generation is observed to enhance the permeability of dendrimers across the amphiphilic membranes. © 2012 the Owner Societies.

Song E.H.,Jilin University | Wen Z.,Jilin University | Jiang Q.,Jilin University
Journal of Physical Chemistry C | Year: 2011

The catalytic oxidation of CO on Cu-embedded graphene is investigated by DFT. The reaction proceeds via a two-step mechanism of CO + O2 → OOCO → CO2 + O and CO + O → CO2. The energy barriers of the former are 0.25 and 0.54 eV, respectively, while the latter is a process with energetic drop. The high activity of Cu-embedded graphene may be attributed to the electronic resonance among electronic states of CO, O 2, and the Cu atom, particularly among Cu-3d, CO-2π*, and O2-2π* orbitals. This good catalytic activity opens a new avenue to fabricate carbon-based catalysts for CO oxidation with lower cost and higher activity. © 2011 American Chemical Society.

Gao N.,Jilin University | Zheng W.T.,Jilin University | Jiang Q.,Jilin University
Physical Chemistry Chemical Physics | Year: 2012

The electronic structures and band gaps of silicene (the Si analogue of graphene) adsorbed with halogen elements are studied using the density functional theory based screened exchange local density approximation method. It is found that the band gaps of silicene adsorbed with F, Cl, Br and I have a nonmonotonic change as the periodic number of the halogen elements increases. This is attributed to the transfer of contributions to band gaps from Si-Si bonding to Si-halogen bonding.

Li J.-L.,Jilin University | Zhang X.,Shanxi Normal University | Huang X.-R.,Jilin University
Physical Chemistry Chemical Physics | Year: 2012

The conversion of benzene to phenol by high-valent bare FeO 2+ was comprehensively explored using a density functional theory method. The conductor-like screen model (COSMO) was used to mimic the role of solvent effect with acetonitrile chosen as the solvent. Two radical mechanisms and one oxygen insertion mechanism were tested for this conversion. The first radical mechanism can also be named as the concerted mechanism in which the hydrogen-atom abstraction process is accomplished via a four-centered transition state. The second radical mechanism is initiated by a direct hydrogen-atom abstraction with a collinear C-H-O transition structure. It is actually the same as the well-accepted rebound mechanism for the C-H bond activation by heme and nonheme iron-oxo catalysts. The third is an oxygen insertion mechanism which is essentially an aromatic electrophilic attack leading to an arenium σ-complex intermediate. The formation of a precomplex with an η 4 coordinate environment in the first radical mechanism is energetically more favorable. However, the relatively lower activation energy barrier of the oxygen insertion mechanism compared to the radical ones makes it highly competitive if the FeO 2+ collides with benzene in the proper orientation. The detailed potential energy surfaces also indicate that the second radical mechanism, i.e., the benzene C-H bond activation through the rebound mechanism, is less favorable. This thorough theoretical study, especially the electronic structure analysis, may offer very important clues for understanding and studying C-H bond activation by iron-based catalysts and enzymatic reactions in protein active pockets.

Xue J.,Jilin University | Shen Y.,Jilin University | He T.,Jilin University
International Journal of Hydrogen Energy | Year: 2011

Double-proveskite YBa0.5Sr0.5Co2O 5+δ (YBSC) was investigated as potential cathode material for intermediate-temperature solid oxide fuel cells (IT-SOFCs). YBSC material exhibited a good chemical compatibility with the La0.9Sr 0.1Ga0.8Mg0.115Co0.085O 2.85 (LSGMC) electrolyte up to 950 °C for 2 h. The substitution of Sr for Ba significantly enhanced the electrical conductivity of the YBSC sample compared to undoped YBaCo2O5+δ, and also slightly increased the thermal expansion coefficient. At 325 °C a semiconductor-metal transition was observed and the maximum electrical conductivity of YBSC was 668 S cm-1. The maximum power densities of the electrolyte-supported single cell with YBSC cathode achieved 650 and 468 mW cm-2 at 850 and 800 °C, respectively. Preliminary results suggested that YBSC could be considered as a candidate cathode material for application in IT-SOFCs. Copyright © 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Dai Q.Q.,Jilin University | Zhu Y.F.,Jilin University | Jiang Q.,Jilin University
Physical Chemistry Chemical Physics | Year: 2012

Stability, electronic and magnetic properties of triangular graphene nanoflakes embedded in graphane (graphane-embedded TGNFs) are investigated by density functional theory. It is found that the interface between the embedded TGNF and graphane is stable since the diffusion of H atoms from the graphane region to the embedded TGNF is energetically unfavorable with high energy barriers. The electronic and magnetic properties of the system completely depend on the embedded TGNF. The band gaps of graphane-embedded ATGNFs (armchair-edged TGNFs) arise due to the quantum confinement, while the special characteristics of nonbonding states of graphane-embedded ZTGNFs (zigzag-edged TGNFs) play an important role in their electronic properties. As the edge sizes increase, the differences of band gaps between graphane-embedded TGNFs and the isolated ones decrease. Furthermore, owing to the partially paired pz orbitals of edge C atoms, graphane-embedded ZTGNFs exhibit a ferrimagnetic ground state with size-dependant total spin being consistent with Lieb's theorem. Our work provides a possible way to obtain TGNFs without physical cutting. This journal is © the Owner Societies.

Xu H.L.,Jilin University | Chin S.L.,Laval University
Sensors | Year: 2011

Powerful femtosecond laser pulses propagating in transparent materials result in the formation of self-guided structures called filaments. Such filamentation in air can be controlled to occur at a distance as far as a few kilometers, making it ideally suited for remote sensing of pollutants in the atmosphere. On the one hand, the high intensity inside the filaments can induce the fragmentation of all matters in the path of filaments, resulting in the emission of characteristic fluorescence spectra (fingerprints) from the excited fragments, which can be used for the identification of various substances including chemical and biological species. On the other hand, along with the femtosecond laser filamentation, white-light supercontinuum emission in the infrared to UV range is generated, which can be used as an ideal light source for absorption Lidar. In this paper, we present an overview of recent progress concerning remote sensing of the atmosphere using femtosecond laser filamentation. © 2010 by the authors.

Sun B.,Jilin University | Yang D.,Jilin University
International Journal of Refrigeration | Year: 2014

The flow boiling heat transfer characteristics of four nano-refrigerants with different mass fractions, qualities, and mass velocities in a horizontal tube were studied. The nano-refrigerants were Cu-R141b, Al-R141b, Al 2O3-R141b, and CuO-R141b. The nanoparticle mass fractions were 0.1 wt%, 0.2 wt%, and 0.3 wt%; the quality ranged within 0.3-0.8; and the mass velocities were 120, 210, and 330 kg m-2 s-1. Results showed that the flow boiling heat transfer was enhanced by nanoparticle addition. The heat transfer coefficient of the nano-refrigerant increased with increased mass fraction, quality, and mass velocity. The mass fraction of nanoparticles was the main factor that influenced the heat transfer coefficient. The heat transfer enhancement effects of the different nano-refrigerants differed, with the highest enhancement achieved using Cu-R141b. At G = 120 kg m-2 s-1 and 0.3 wt% mass fraction, the maximum heat transfer coefficient of Cu-R141b increased by 49% (average increase = 27%). © 2013 Elsevier Ltd and IIR. All rights reserved.

Jia J.,Harbin Engineering University | Abudula A.,Hirosaki University | Wei L.,Jilin University | Sun B.,Harbin Engineering University | Shi Y.,Harbin Engineering University
Renewable Energy | Year: 2015

An integrated process of biomass gasification and solid oxide fuel cells (SOFC) is investigated using energy and exergy analyses. The performance of the system is assessed by calculating several parameters such as electrical efficiency, combined heat and power efficiency, power to heat ratio, exergy destruction ratio, and exergy efficiency. A performance comparison of power systems for different gasification agents is given by thermodynamic analysis. Exergy analysis is applied to investigate exergy destruction in components in the power systems. When using oxygen-enriched air as gasification agent, the gasifier reactor causes the greatest exergy destruction. About 29% of the chemical energy of the biomass is converted into net electric power, while about 17% of it is used to for producing hot water for district heating purposes. The total exergy efficiency of combined heat and power is 29%. For the case in which steam as the gasification agent, the highest exergy destruction lies in the air preheater due to the great temperature difference between the hot and cold side. The net electrical efficiency is about 40%. The exergy combined heat and power efficiency is above 36%, which is higher than that when air or oxygen-enriched air as gasification agent. © 2015 Elsevier Ltd.

Wang X.,Jilin University | Wang Y.,Jilin University | Bi S.,Jilin University | Chen X.,Jilin University | And 2 more authors.
Advanced Functional Materials | Year: 2014

Optically transparent antibacterial films capable of healing scratches and restoring transparency are fabricated by exponential layer-by-layer assembly of branched polyethylenimine (bPEI)/poly(acrylic acid) (PAA) films and post-diffusion of cetyltrimethylammonium bromide micelles encapsulated with antibacterial agent triclosan. The triclosan-loaded bPEI/PAA transparent films can effectively inhibit the growth of gram-positive and gram-negative bacteria by the sustained release of triclosan molecules. Healing of multiple scratches on the triclosan-loaded bPEI/PAA films can be conveniently achieved by immersing the films in water or spraying water on the damaged films, which also fully restores their transparency. The self-healing ability of these transparent antibacterial films originates from the ability of bPEI and PAA to flow and recombine in the presence of water. The triclosan-loaded bPEI/PAA films have satisfactory mechanical stability under ambient conditions, and thus show potential for application as transparent protective films with antibacterial properties. Optically transparent antibacterial films capable of healing scratches to restore transparency are fabricated by incorporating triclosan into branched polyethylenimine/poly(acrylic acid) multilayer films. Sustained release of triclosan endows the films with antibacterial properties. Film transparency can be healed multiple times by immersing the films in water or spraying water on them. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Lanthanide-doped core-shell upconversion nanocrystals (UCNCs) have tremendous potential for applications in many fields, especially in bio-imaging and medical therapy. As core-shell UCNCs are mostly synthesized in organic solvents, tedious organic-aqueous phase transfer processes are usually needed for their use in bio-applications. Herein, we demonstrate the first example of one-step synthesis of highly luminescent core-shell UCNCs in the "aqueous" phase under mild conditions using innocuous reagents. A microwave-assisted approach allowed for layer-by-layer epitaxial growth of a hydrophilic NaGdF4 shell on NaYF4:Yb, Er cores. During this process, surface defects of the nanocrystals could be gradually passivated by the homogeneous shell deposition, resulting in obvious enhancement in the overall upconversion emission efficiency. In addition, the up-down conversion dual-mode luminescent NaYF4:Yb, Er@NaGdF4:Ce, Ln (Eu, Tb, Sm, Dy) nanocrystals were also synthesized to further validate the successful formation of the core-shell structure. More significantly, based on their superior solubility and stability in water solution, high upconversion efficiency and Gd-doped predominant X-ray absorption, the as-prepared NaYF4:Yb, Er@NaGdF4 core-shell UCNCs exhibited high contrast in in vitro cell imaging and in vivo X-ray computed tomography (CT) imaging, demonstrating great potential as multiplexed luminescent biolabels and CT contrast agents.

Liu H.,Jilin University | Liu L.,Jilin University | Zhang H.,Northeast Normal University
Journal of Biomedical Informatics | Year: 2010

Selecting relevant and discriminative genes for sample classification is a common and critical task in gene expression analysis (e.g. disease diagnostic). It is desirable that gene selection can improve classification performance of learning algorithm effectively. In general, for most gene selection methods widely used in reality, an individual gene subset will be chosen according to its discriminative power. One of deficiencies of individual gene subset is that its contribution to classification purpose is limited. This issue can be alleviated by ensemble gene selection based on random selection to some extend. However, the random one requires an unnecessary large number of candidate gene subsets and its reliability is a problem. In this study, we propose a new ensemble method, called ensemble gene selection by grouping (EGSG), to select multiple gene subsets for the classification purpose. Rather than selecting randomly, our method chooses salient gene subsets from microarray data by virtue of information theory and approximate Markov blanket. The effectiveness and accuracy of our method is validated by experiments on five publicly available microarray data sets. The experimental results show that our ensemble gene selection method has comparable classification performance to other gene selection methods, and is more stable than the random one. © 2009 Elsevier Inc. All rights reserved.

Wang C.,Jilin University | Yan J.,Jilin University | Cui X.,Jilin University | Wang H.,Jilin University
Journal of Colloid and Interface Science | Year: 2011

In this paper, we present a novel method for the preparation of raspberry-like monodisperse magnetic hollow hybrid nanospheres with γ-Fe2O3@SiO2 particles as the outer shell. PS@Fe3O4@SiO2 composite nanoparticles were successfully prepared on the principle of the electrostatic interaction between negatively charged silica and positively charged polystyrene, and then raspberry-like magnetic hollow hybrid nanospheres with large cavities were achieved by means of calcinations, simultaneously, the magnetite (Fe3O4) was transformed into maghemite (γ-Fe2O3). Transmission electron microscopy (TEM) demonstrated that the obtained magnetic hollow silica nanospheres with the perfect spherical profile were well monodisperse and uniform with the mean size of 253nm. The Fourier transform infrared (FTIR) spectrometry, energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) provided the sufficient evidences for the presence of Fe3O4 in the silica shell. Moreover, the magnetic hollow silica nanospheres possessed a characteristic of superparamagnetic with saturation magnetization value of about 7.84emu/g by the magnetization curve measurement. In addition, the nitrogen adsorption-desorption measurement exhibited that the pore size, BET surface area, pore volume of magnetic hollow silica nanospheres were 3.5-5.5nm, 307m2g-1 and 1.33cm3g-1, respectively. Therefore, the magnetic hollow nanospheres possess a promising future in controlled drug delivery and targeted drug applications. © 2010 Elsevier Inc.

Tan G.,University of Tennessee Health Science Center | Tan G.,Jilin University | Shi Y.,University of Tennessee Health Science Center | Wu Z.-H.,University of Tennessee Health Science Center
Biochemical and Biophysical Research Communications | Year: 2012

DNA damage response upon UV radiation involves a complex network of cellular events required for maintaining the homeostasis and restoring genomic stability of the cells. As a new class of players involved in DNA damage response, the regulation and function of microRNAs in response to UV remain poorly understood. Here we show that UV radiation induces a significant increase of miR-22 expression, which appears to be dependent on the activation of DNA damage responding kinase ATM (ataxia telangiectasia mutated). Increased miR-22 expression may result from enhanced miR-22 maturation in cells exposed to UV. We further found that tumor suppressor gene phosphatase and tensin homolog (PTEN) expression was inversely correlated with miR-22 induction and UV-induced PTEN repression was attenuated by overexpression of a miR-22 inhibitor. Moreover, increased miR-22 expression significantly inhibited the activation of caspase signaling cascade, leading to enhanced cell survival upon UV radiation. Collectively, these results indicate that miR-22 is an important player in the cellular stress response upon UV radiation, which may promote cell survival via the repression of PTEN expression. © 2011 Elsevier Inc..

Song N.,Jilin University | Yang Y.-W.,Jilin University
Science China Chemistry | Year: 2014

Synthetic macrocycles, a typical type of building block for molecular recognition and self-assembly, are crucial to supramolecular chemistry and materials science. Since 2008, a new generation of synthetic macrocyclic hosts, pillarenes and their abundant derivatives, which consist of hydroquinone units linked by methylene bridges at 2,5-positions, have been the focus of much research. Numerous studies on their host-guest properties and the fabrication of supramolecular assemblies have demonstrated that pillarenes and their derivatives possess many advantages that facilitate their applications in many research fields. Herein we summarize and classify the applications of pillarenes in terms of artificial transmembrane channels, controlled delivery systems, dispersion of carbon hybrid materials, extraction and absorption, liquid crystals, metal-organic frameworks, sensing and detection, stabilization of nanoparticles (Au/Ag/CdTe), and other typical biological applications. We also provide an overview of future developments in pillarene chemistry. © 2014 Science China Press and Springer-Verlag Berlin Heidelberg.

Liu Z.,Jilin University | Xu K.,Jilin University | Sun H.,Jilin University | Yin S.,Jilin University
Small | Year: 2015

A template-free, one-step and one-phase synthesis of single-layer MnO2 nanosheets has been developed via a redox reaction between KMnO4 and sodium dodecyl sulfate (SDS). The successful formation of single-layer MnO2 nanosheets has been confirmed by the characteristic absorption around 374 nm and the typical thickness of ∼0.95 nm. The slow redox reaction controlled by the gradual hydrolysis of SDS is found to be the key factor for the successful formation of single-layer nanosheets. SDS not only serves as the precursor of dodecanol to reduce KMnO4, but also aids the formation of single-layer MnO2 nanosheets as a structure-inducing agent. The resultant single-layer MnO2 nanosheets possess superior specific capacitance, which can be attributed to the extended surface and high porosity of MnO2 nanosheets on the electrode. The MnO2 nanosheets also show excellent durability, retaining 91% of the starting capacitance after 10 000 charge/discharge cycles. Moreover, the symmetric pseudocapacitor based on the synthesized single-layer MnO2 nanosheets exhibits a high specific capacitance, indicating great potential for real energy storage. Therefore, it has been demonstrated for the first time that a single readily available reagent, SDS, can play multiple roles in reducing KMnO4 to conveniently yield single-layer MnO2 nanosheets as a high-performance pseudocapacitive material. A convenient, one-step and one-phase synthesis of single-layer MnO2 nanosheets is developed via a redox reaction between KMnO4 and sodium dodecyl sulfate (SDS). Interestingly, SDS functions as both a reductant and a structure-inducing agent in the reaction. The resultant MnO2 nanosheets exhibit high specific capacitance and excellent durability, providing a promising pseudocapacitive material for real energy storage devices. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wang W.,Jilin University | Qin S.,Yanbian University | Zhao L.,Jilin University
Biomedicine and Pharmacotherapy | Year: 2015

Pretreatment with chemotherapeutic agents could sensitize human lung adenocarcinoma cells to the lyses of cytokine-induced killer (CIK) cells, however, the mechanism still unclear. We hypothesized that chemotherapeutic agents could induced immunogenic modulation (IM) and calreticulin (CRT) expression and enhanced the cytokine-induced killer (CIK) cells-mediated killing. Here, using docetaxel, one of the most widely used cancer chemotherapeutic agents, as a model, we examined the molecular and immunogenic consequences of chemotherapeutic agent exposure in lung adenocarcinoma cell SPC-A1 cells. Our results showed that the human lung adenocarcinoma cells displayed an increased sensitization to lyses of CD3+ CD56+ CIK cells after treatment with nonlethal/sublethal doses of docetaxel in vitro. Docetaxel treatment of tumor cells did not induce ATP or high-mobility group box 1 (HMGB1) secretion, or cell death. However, calreticulin (CRT) exposure was observed. Enhanced killing by CIK cells was mediated largely by CRT membrane translocation, as determined by functional knockdown of CRT, or CRT blocking antibody. This study provides evidence that the pretreatment with chemotherapeutic agents can sensitize tumor cells to the lyses of CD3+ CD56+ CIK cells in vitro through inducing immunogenic modulation and upregulating in target cells. © 2014 Elsevier Masson SAS.

Jiang K.,Jilin University | Fei T.,Jilin University | Zhang T.,Jilin University
Sensors and Actuators, B: Chemical | Year: 2014

A novel porous polymer was synthesized by Friedel-Crafts alkylation polymerization, and the structure and characteristic of the polymer was determined by Fourier transform infrared spectroscopy (FTIR), N2 adsorption/desorption analysis, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The obtained polymer was used to prepare humidity sensitive composites by loading LiCl. Compared with the pure polymer, LiCl-loaded composites showed improved humidity sensing properties and the 4 wt% LiCl/polymer sensor showed the best sensing properties. The impedance of the optimum sensor changed near four orders of magnitude over the whole humidity range, with a good linearity, little hysteresis, good stability and short response and recovery times (2 and 7 s, respectively). The complex impedance plots were used to research conductive mechanism. © 2014 Elsevier B.V. All rights reserved.

Wu N.,Jilin University | Li Y.,Jilin University | Yang B.,Jilin University
IEEE Transactions on Geoscience and Remote Sensing | Year: 2011

A main target of seismic data processing is to remove the surface waves and improve the quality of seismic records. Here, we propose a Co-Core Trace (CCT) transform filtering based on the Trace transform from image processing and apply it to seismic surface wave attenuation. The CCT transform is designed according to the distribution and propagation of the surface waves. In the CCT transform domain, the energies of surface waves are significantly enhanced and could be filtered out with a relative threshold, while the reflection events are saved due to the conspicuous disparity. Experiments on both synthetic model and field data demonstrate that the proposed algorithm performs well both in surface wave attenuation and reflected signal preservation, besides presenting advantages over some conventional methods. © 2011 IEEE.

Xie H.-R.,Jilin University | Hu L.-S.,Jilin University | Li G.-Y.,Jilin University
Chinese Medical Journal | Year: 2010

Objective To evaluate the human neuroblastoma SH-SY5Y cell line as an in vitro model of dopaminergic (DAergic) neurons for Parkinson's disease (PD) research and to determine the effect of differentiation on this cell model. Data sources The data of this review were selected from the original reports and reviews related to SH-SY5Y cells published in Chinese and foreign journals (Pubmed 1973 to 2009). Study selection After searching the literature, 60 articles were selected to address this review. Results The SH-SY5Y cell line has become a popular cell model for PD research because this cell line posses many characteristics of DAergic neurons. For example, these cells express tyrosine hydroxylase and dopamine-β-hydroxylase, as well as the dopamine transporter. Moreover, this cell line can be differentiated into a functionally mature neuronal phenotype in the presence of various agents. Upon differentiation, SH-SY5Y cells stop proliferating and a constant cell number is subsequently maintained. However, different differentiating agents induce different neuronal phenotypes and biochemical changes. For example, retinoic acid induces differentiation toward a cholinergic neuronal phenotype and increases the susceptibility of SH-SY5Y cells to neurotoxins and neuroprotective agents, whereas treatment with retinoic acid followed by phorbol ester 12-O-tetradecanoylphorbol-13-acetate results in a DAergic neuronal phenotype and decreases the susceptibility of cells to neurotoxins and neuroprotective agents. Some differentiating agents also alter kinetics of 1-methyl-4-phenyl-pyridinium (MPP +) uptake, making SH-SY5Y cells more similar to primary mesencephalic neurons. Conclusions Differentiated and undifferentiated SH-SY5Y cells have been widely used as a cell model of DAergic neurons for PD research. Some differentiating agents afford SH-SY5Y cells with more potential for studying neurotoxicity and neuroprotection and are thus more relevant to experimental PD research.

Liu S.,Northeastern University China | Su X.,Jilin University
RSC Advances | Year: 2014

As a novel nanomaterial, I-III-VI type quantum dots have been a major focus of research and development in the past decade, which can be attributed to their tunable fluorescence emission wavelengths, high photostability and low toxicity of chemical composition. In addition, I-III-VI type quantum dots have fluorescence emission wavelengths in the near-infrared regions, and thus have potential applications in bioimaging. In this review, several recent advances regarding I-III-VI type quantum dots are summarized, including synthetic methods, characteristics and some applications. Furthermore, we discuss the prospects and challenges related to this novel type of quantum dots. This journal is © the Partner Organisations 2014.

Ren L.,Jilin University | Liang Y.,Jilin University
Science China Technological Sciences | Year: 2014

The bionic consciousness, idea, and practice opened a unique path for the progress of mankind, the development of the society, and the innovation of science and technology from the subconscious bionic activities of the ancient humans to the significant bionic designs in modern engineering. Nowadays, driven by the practical demand of human beings, bionics becomes an important factor for the sustainable development of technology. A lot of new and outstanding innovations have been produced through the effective interactions between bionics, technology, and demand. The stronger the interactions, the greater the innovation success would be. In this article, the basic factors such as the connotation, characteristics, and interactions of bionic demands, bionic models, bionic simulations, and bionic products were explained, which are the indispensable basic knowledge for improving the ability of innovation especially for the original one, realizing the design and innovation of new technology and manufacturing for better bionic products. © 2014 Science China Press and Springer-Verlag Berlin Heidelberg.

Zhou Y.,Jilin University | Xie G.,Jilin University | Wang J.,Jilin University | Yang S.,Jilin University
Canadian Journal of Cardiology | Year: 2012

Background: Information is limited about the correlation between cardiovascular risk factors (CRFs) and autonomic nervous system (ANS) activity in children. Methods: In all, 180 children aged 9 to 11 years were enrolled. Heart rate variability, obtained by 24-hour Holter recordings, was analyzed for ANS activity by measuring standard deviation of normal-to-normal RR intervals (SDNN), the standard deviation of the averaged normalto- normal RR intervals, the root mean square of successive differences (RMSSD), low-frequency (LF), high-frequency (HF), and ratio of LF to HF. CRFs were defined as hypertension, dyslipidemia, obesity, and elevated fasting blood glucose. Children were subdivided into 4 levels: 0 (no CRF), 1 (1 CRF), 2 (2 CRFs), or 3 (3 or more CRFs). Altered ANS activity of each level was assessed. The correlation between CRF and ANS activity was analyzed by stepwise multiple regression. Results: With an increasing number of CRFs, there was a progressive elevation in blood pressure, obesity indices, most blood lipoprotein concentrations, and fasting blood glucose. Moreover, increase in the number of CRFs was associated with progressive reduction of SDNN, RMSSD, LF, and HF. Systolic blood pressure (SBP) correlated negatively with SDNN, RMSSD, LF, and HF. Obesity indices had a negative correlation with RMSSD and HF. As the number of CRFs increases, so does the extent of abnormal clustering of CRFs and changes in ANS activity. Conclusions: Obesity and elevated SBP are associated with marked alterations in ANS activity, obesity with reduced vagal nerve activity, and elevated SBP with altered vagal and sympathetic nerve activity. © 2012 Canadian Cardiovascular Society.

Zhang P.,Jilin University | Wang H.,Jilin University | Liu H.,Jilin University | Li M.,Jilin University
Langmuir | Year: 2010

New low-molecular-mass organic gelators (LMOGs) bearing hydrazine linkage and end-capped by phenyl, namely 1,4-bis[(3,4-bisalkoxyphenyl)hydrozide] phenylene (BPH-n, n = 4, 6, 8, 10), were designed and synthesized. These organogelators have shown great ability to gel a variety of organic solvents to form stable organogels with the critical gelation concentration as low as 8.7 × 10-4 mol L-1 (0.06 wt %). The formed gel has a high gel-sol transition temperature (Tgel) at low gelation concentration. Aggregation-induced emission (AIE) has been observed after gelation though conventional chromophore units not incorporated inBPH-n. The fluorescence quantumyields of xerogel are 2 orders higher than that of dilute solution. In addition, the BPH-n (n=6, 8, 10) exhibited thermotropic hexagonal column (Colh) mesophase, which are stable at room temperature as revealed by differential scanning calorimetry (DSC), polarized optical microscopy (POM), and X-ray diffraction (XRD) studies. © 2010 American Chemical Society.

Chen X.-K.,Jilin University | Zou L.-Y.,Jilin University | Guo J.-F.,Northeast Normal University | Ren A.-M.,Jilin University
Journal of Materials Chemistry | Year: 2012

The aromatic diimides are among the most promising and versatile candidates for organic optoelectronic materials due to their commercial availability, low cost, excellent optical and electric performance, such as naphthalene, anthracene and perylene diimides. But, so far, the problem is not clarified - is a five- or six-membered imide ring more helpful for n-type organic semiconductor materials? The work investigated in detail and compared various properties for molecules with a five-/six-membered imide ring from the following aspects: (1) molecular stability, reaction activity, geometries, frontier molecular orbitals as well as oxidation and reduction abilities at the single-molecule level; (2) the variation of transfer integrals at the various molecular stacking motifs; (3) the estimate of carrier mobility and its anisotropy for the actual molecule crystals. The results indicate that molecules with a six-membered imide ring should be more suitable for n-type organic semiconductor materials. This journal is © The Royal Society of Chemistry 2012.

Li Y.,Jilin University | Yu J.,Jilin University
Chemical Reviews | Year: 2014

Spheres are attracted to each other when they are close, which ensures the close packing of spheres. Spheres also repel each other strongly if they overlap, ensuring the hardness of the spheres. At the beginning of the packing procedure, a small number of hexagonal close packed spheres are placed into the zeolite framework without overlapping any framework atom. An excess of spheres are supplied outside the unit cell. The concept of natural tiling can be one of the solutions. According to the theory of tiling, a three dimensional net can be decomposed into a number of face sharing, edge-sharing, and vertex-sharing three-dimensional polyhedral tiles. The way all of the tiles assemble together is the tiling of the net. By comparing the T-ring graphs corresponding to different probes, one can easily generate preliminary conclusions about the selectivity of mixtures of guest species corresponding to a specific zeolite framework.

Xu M.,Jilin University | Li C.,Jilin University | Zhang X.,Jilin University | Wu Y.,Jilin University
International Geology Review | Year: 2014

In this paper, we summarize results of studies on ophiolitic mélanges of the Bangong-Nujiang suture zone (BNSZ) and the Shiquanhe-Yongzhu-Jiali ophiolitic mélange belt (SYJMB) in central Tibet, and use these insights to constrain the nature and evolution of the Neo-Tethys oceanic basin in this region. The BNSZ is characterized by late Permian-Early Cretaceous ophiolitic fragments associated with thick sequences of Middle Triassic-Middle Jurassic flysch sediments. The BNSZ peridotites are similar to residual mantle related to mid-ocean-ridge basalts (MORBs) where the mantle was subsequently modified by interactions with the melt. The mafic rocks exhibit the mixing of various components, and the end-members range from MORB-types to island-arc tholeiites and ocean island basalts. The BNSZ ophiolites probably represent the main oceanic basin of the Neo-Tethys in central Tibet. The SYJMB ophiolitic sequences date from the Late Triassic to the Early Cretaceous, and they are dismembered and in fault contact with pre-Ordovician, Permian, and Jurassic-Early Cretaceous blocks. Geochemical and stratigraphic data are consistent with an origin in a short-lived intra-oceanic back-arc basin. The Neo-Tethys Ocean in central Tibet opened in the late Permian and widened during the Triassic. Southwards subduction started in the Late Triassic in the east and propagated westwards during the Jurassic. A short-lived back-arc basin developed in the middle and western parts of the oceanic basin from the Middle Jurassic to the Early Cretaceous. After the late Early Jurassic, the middle and western parts of the oceanic basin were subducted beneath the Southern Qiangtang terrane, separating the Nierong microcontinent from the Southern Qiangtang terrane. The closing of the Neo-Tethys Basin began in the east during the Early Jurassic and ended in the west during the early Late Cretaceous. © 2014 Taylor and Francis.

Liu B.,Jilin University | Liu B.,University of North Carolina at Chapel Hill | Tonkonogy S.L.,Jilin University | Tonkonogy S.L.,University of North Carolina at Chapel Hill | And 2 more authors.
Gastroenterology | Year: 2011

Background & Aims: Mice that are deficient in interleukin (IL)-10 develop colitis, mediated by T-helper (Th)1 and Th17 cells, and IL-10producing regulatory T (Treg) cells suppress colitis, implicating IL-10 in maintaining mucosal homeostasis. We assessed the relative importance of immunoregulatory IL-10 derived from T cells or from antigen presenting cells (APCs) in development of intestinal inflammation. Methods: CD4+ cells from germ-free (GF) or specific pathogen-free (SPF) IL-10-/- or wild-type mice were injected into IL-10-/-, Rag2-/- mice or Rag2-/- mice that express IL-10. After 68 weeks, we evaluated inflammation, spontaneous secretion of cytokines from colonic tissue, and mRNA levels of the transcription factor T-bet and the immunoregulatory cytokine transforming growth factor (TGF)-β. CD4+ T cells were co-cultured with bacterial lysate-pulsed APCs and assayed for cytokine production, FoxP3 expression, and TGF-β-mediated Smad signaling. Results: CD4+ cells from GF or SPF IL-10-/- or wild-type mice induced more severe colitis and higher levels of inflammatory cytokines in IL-10-/-, Rag2-/- mice than in IL-10-replete, Rag2 -/- mice. Co-cultures of IL-10-/- or wild-type CD4 + T cells plus bacterial lysate-pulsed APCs from IL-10-/- mice contained more interferon (IFN)-γ, IL-12/23p40, and IL-17 than co-cultures of the same T cells plus APCs from wild-type mice. CD11b+ APCs were required for these effects. Blocking IL-10 receptors increased production of IFN-γ and IL-12/23p40 whereas exogenous IL-10 suppressed these cytokines. IL-10producing APCs induced TGF-β-mediated, retinoic acid-dependent, differentiation of FoxP3+ Treg cells, whereas blocking the retinoic acid receptor, in vitro and in vivo, reduced proportions of FoxP3+ Treg cells. Conclusions: IL-10 produced by APCs regulates homeostatic T-cell responses to commensal bacteria. © 2011 AGA Institute.

Oxidative stress is widely implicated in the death of retinal ganglion cells associated with various optic neuropathies. Agonists of the dopamine D(1) receptor have recently been found to be potentially neuroprotective against oxidative stress-induced injury. The goal of this study was to investigate whether SKF83959, a next-generation high-affinity D(1) receptor agonist, could protect retinal ganglion cell 5 (RGC-5) cells from H(2)O(2)-induced damage and the molecular mechanism involved. We examined expression of the D(1) receptor in RGC-5 cells with reverse-transcription-PCR and immunoblotting and assessed neuroprotection using propidium iodide staining and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. In addition, we monitored the activation and involvement of members of mitogen-activated protein kinase family, extracellular signal-regulated kinase (ERK), p38 and c-Jun NH(2)-terminal kinase, with western blot and specific inhibitors. We found that the D(1) receptor was expressed in RGC-5 cells, but the sequence analysis suggested this cell line is from mouse and not rat origin. SKF83959 exhibited a remarkable neuroprotective effect on H(2)O(2)-damaged RGC-5 cells, which was blocked by the specific D(1) receptor antagonist, SCH23390. ERK and p38 were activated by SKF83959, and pretreatment with their inhibitors U0126 and SB203580, respectively, significantly blunted the SKF83959-induced cytoprotection. However, the specific c-Jun NH(2)-terminal kinase inhibitor, SP600125, had no effect on the SKF83959-induced protection. We conclude that SKF83959 attenuates hydrogen peroxide-induced injury in RGC-5 cells via a mechanism involving activation of the ERK and p38 pathways and the D(1) receptor is a potential molecular target for developing neuroprotective drugs.

Liu Z.-Q.,Jilin University
Current Organic Chemistry | Year: 2014

High efficiency in the organic synthesis makes the multicomponent reaction (MCR) an attractive research field, in which some three-component reactions such as the Strecker (found in 1850), Hantzsch (1882), Biginelli (1891), Mannich (1912), and Passerini (1921) were widely spread, followed by the findings of some four-component reactions such as the Bucherer Bergs and Asinger reactions found in 1929 and 1956, respectively. However, the reaction among ketone, amine, isonitrile, and carboxylic acid to form bisamide found by Ivar K. Ugi in 1959 still takes the most important position in the MCRs because the Ugi four-component reaction (Ugi 4CR) occurs among four organic reagents in methanol or other popular solvents without the aid of any catalysts. Thus, Ugi 4CR represents a selfresembling process among organic reagents and therefore implies the possibility that an organic reaction may involve more than four reagents within one pot operation. Thus, Ugi 4CR can be regarded as the breakthrough in the research of MCRs. Many published reviews summarize the Ugi 4CR from different viewpoints, but the aim of the presented review on Ugi 4CR together with Passerini three-component reaction (Passerini 3CR) is to introduce a successful mode for the study on MCRs, in which the research on a MCR may involve four aspects including mechanism, substrate, catalyst, and application. The quantum calculation on the energy variation of Ugi 4CR reveals that the addition of isocyanide to imine controls the reaction rate of Ugi 4CR, and imine is generated via the reaction between the amine and ketone at the first step in Ugi 4CR. As a result, the investigation on the substrates of Ugi 4CR focuses on the formation of imine and the resources of carboxylic acid and ketone. Moreover, some catalysts are employed to induce the diastereoisomer ratio because a chiral center is involved in the product of Ugi 4CR. In addition, Lewis acid is used to activate the inert reagents or to drive the further reactions based on Ugi 4CR products. The application of Ugi 4CR is not the major concern in this review because many previous reviews have focused on this topic. Only some recently published results are documented herein. For example, Ugi 4CR can be used to construct macromolecules with complicated topological structure, to introduce medicinal molecule into nanoparticles, and to synthesize biological-related molecules. Finally, a successful model for the research on MCR can be summarized from the study on Ugi 4CR. Understanding mechanism is the basis for investigating MCR, followed by expanding the suitable substrates and exploring the chiral catalysts. As a result, the MCR can be widely applied to synthesize various molecules. © 2014 Bentham Science Publishers.

Song Y.,Jilin University | Zhu S.,Jilin University | Yang B.,Jilin University
RSC Advances | Year: 2014

Nanosized fluorescent carbon particles, namely, carbon dots (CDs), are a kind of fluorescent material that has drawn increasing attention in recent years. CDs have size-, surface chemistry-, and wavelength-dependent luminescence emission, which is different from traditional semiconductor-based quantum dots. Moreover, with excellent chemical stability, good biocompatibility, low toxicity, up-conversion emission, resistance to photo bleaching, as well as easy chemical modifications, CDs are promising for substantial applications in numerous areas: bioimaging, sensors, and energy-related devices. Herein, three kinds of fluorescent dots are reviewed: graphene quantum dots (GQDs), carbon nanodots (CNDs) and polymer dots (PDs). After the first reported CDs prepared from electrophoretic analysis and purification of fluorescent carbon nanotube fragments, there were hundreds of publications focusing on fluorescent CDs. Bioimaging was one of the most common applications of the CDs; therefore, in this review, most of the chosen reference papers were related to bioimaging based on CDs. © 2014 the Partner Organisations.

Li L.,CAS Changchun Institute of Applied Chemistry | Li L.,Jilin University | Wu Z.,CAS Changchun Institute of Applied Chemistry | Wu Z.,University of Chinese Academy of Sciences | And 3 more authors.
Energy and Environmental Science | Year: 2014

To meet the rapid development of flexible, portable, and wearable electronic devices, extensive efforts have been devoted to develop matchable energy storage and conversion systems as power sources, such as flexible lithium-ion batteries (LIBs), supercapacitors (SCs), solar cells, fuel cells, etc. Particularly, during recent years, exciting works have been done to explore more suitable and effective electrode/electrolyte materials as well as more preferable cell configuration and structural designs to develop flexible power sources with better electrochemical performance for integration into flexible electronics. An overview is given for these remarkable contributions made by the leading scientists in this important and promising research area. Some perspectives for the future and impacts of flexible energy storage and conversion systems are also proposed. © The Royal Society of Chemistry 2014.

Zhang X.,Jilin University | Liu X.,Jilin University | Lu R.,Jilin University | Zhang H.,Jilin University | Gong P.,Jilin University
Journal of Materials Chemistry | Year: 2012

Nanofibrils emitting strong red light have been fabricated from triphenylamine functionalized β-diketone-boron difluoride 1, via a rapid solution dispersion approach. It is found that the nanofibrils based on compound 1 can sense volatile organic amines and pyridine selectively. For example, the fluorescence of the nanofibril-based film can be quenched quickly and significantly upon exposed to the vapors of n-butylamine, dibutylamine, tributylamine, triethylamine, cyclohexylamine, hydrazine, aniline, N,N-dimethylaniline and pyridine instead of other common reagents. Notably, the response time of the nanofibril-based film to aniline is ca. 1.06 s, which is one of the fastest fluorescent responses to aniline. The detection limit of the nanofibril-based film for aniline vapor can reach ca. 100 ppb. We suggest that the high sensitivity and fast response of the sensory nanofibrils towards gaseous amines may come from the high surface-to-volume ratio and large interspace in the nanofibril-based networks, which favor the enhanced adsorption, accumulation and diffusion of gaseous molecules. In addition, the amplified fluorescence quenching induced by the enhanced intermolecular exciton diffusion along the long axis of the 1D nanostructures is another reason for the high performance of the obtained sensory nanomaterial. © The Royal Society of Chemistry 2011.

Wang W.,Dalian University of Technology | Wang W.,Jilin University | Liu X.,Dalian University of Technology
Information Sciences | Year: 2015

In spite of the impressive diversity of models of fuzzy forecasting, there is still a burning need to arrive at models that are both accurate and highly interpretable. This study proposes a new fuzzy forecasting model designed with the use of the two key techniques, namely clustering and axiomatic fuzzy set (AFS) classification. First, clustering algorithm is utilized to generate clustering-based intervals. Second, the fuzzy trend labeled training data set is constructed based on fuzzy logic relationships and fuzzy trends of historical samples. Then, the AFS classification is exploited to yield the semantic interpretation of each fuzzy trend. The main novelty is that the proposed model not only predicts the value but can also capture the trend prevailing in the time series, and obtain its semantic interpretation. The Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX), inventory demand, and Spanish electricity prices are used in a series of experiments. The results show that the proposed model has both good interpretability and accuracy. © 2014 Elsevier Inc. All rights reserved.

Wu N.,Jilin University | Li Y.,Jilin University | Yang B.,Jilin University
IEEE Geoscience and Remote Sensing Letters | Year: 2011

The time-frequency peak filtering (TFPF) is an effective tool in random-noise attenuation and has been applied to seismic record denoising in recent years. The window length (WL) of the time-frequency distribution (TFD) is the key to the conventional TFPF technology. A fixed WL is not optimal for both the low- and high-frequency components at the same time; an adaptive WL results in serious distortion of the reflected waveform. In this letter, we discuss a modified TFPF along the radial-trace direction and prove its advantage in TFD window selection. Experiments on both synthetic models and field data show that the radial-trace TFPF result is no longer much influenced by the WL as the conventional TFPF. Furthermore, it can provide better performance in both random-noise attenuation and reflected signal preservation with a fixed WL. © 2011 IEEE.

Fan L.,Jilin University | Xue M.,Jilin University | Kang Z.,Jilin University | Li H.,Jilin University | Qiu S.,Jilin University
Journal of Materials Chemistry | Year: 2012

For the first time, an electrospinning technique has been introduced into the synthesis of supported microporous membranes. This new approach is suitable for various substrates, especially tubes, with the possibility of large-area processing. We can precisely control the thickness of the seed layer and obtain a continuous and uniform seed coating on the support surface. The zeolite imidazolate framework-8 was selected as a candidate to demonstrate the effectiveness of this method, by which, defect-free and well-intergrown ZIF-8 membranes have been successfully synthesized. Single gas permeance of H 2, N2, CH4, CO2 and binary mixtures experiments for H2-CO2, H2-CH4, H2-N2 were carried out. The results indicated that the ZIF-8 membrane prepared through this new approach had better H2 selectivity and gas permeability. © 2012 The Royal Society of Chemistry.

Liu F.,Shaoxing University | Sun J.,Jilin University | Zhu L.,Jilin University | Meng X.,Zhejiang University | And 2 more authors.
Journal of Materials Chemistry | Year: 2012

Graphene with its two-dimensional sheet of sp 2-hybridized carbon is a hot topic in the fields of materials and chemistry due to its unique features. Herein, we demonstrate that sulfated graphene is an efficient solid catalyst for acid-catalyzed liquid reactions. The sulfated graphene was synthesized from a facile hydrothermal sulfonation of reduced graphene oxide with fuming sulfuric acid at 180 °C. Combined characterizations of XRD, Raman, and AFM techniques show that G-SO 3H has a sheet structure (1-4 layers). IR spectroscopy shows that G-SO 3H has a S = O bond, and the XPS technique confirms the presence of an S element in G-SO 3H. Acid-base titration indicates that the acidic concentration of sulfonic groups in the sulfated graphene is 1.2 mmol g -1. TG curves shows that the decomposition temperature (268 °C) of the sulfonic groups on the sulfated graphene is much higher than that of conventional SO 3H-functionalized ordered mesoporous carbon (237 °C). Catalytic tests of the esterification of acetic acid with cyclohexanol, the esterification of acetic acid with 1-butanol, the Peckmann reaction of resorcinol with ethyl acetoacetate, and the hydration of propylene oxide show that sulfated graphene is much more active than the conventional solid acid catalysts of Amberlyst 15, OMC-SO 3H, SO 3H-functionalized ordered mesoporous silica (SBA-15-SO 3H), graphene oxide, and reduced graphene oxide, which is attributed to the fact that the sulfated graphene almost has no limitation of mass transfer due to its unique sheet structure. Very importantly, the sulfated graphene has extraordinary recyclability in these reactions, which is attributed to the stable sulfonic groups on the sulfated graphene. The advantages, including high activities and good recyclability as well as simple preparation, are potentially important for industrial applications of the sulfated graphene as an efficient heterogeneous solid acid catalyst in the future. © The Royal Society of Chemistry 2012.