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Fu Z.,Jilin University | Wang X.,Jilin University | Yang Y.,Hebei University | Wu Z.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Dalton Transactions | Year: 2014

Uniform and well-crystallized calcium fluorapatite [Ca5(PO 4)3F, FAP] microrods have been successfully synthesized by a facile one-step hydrothermal synthesis method using sodium citrate as the crystal modifier. X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), photoluminescence (PL), photoluminescent excitation spectra (PLE) and decay studies were employed to characterize the samples. The electronic structure and orbital population of FAP were also determined by means of density functional theory calculations. Under ultraviolet irradiation, the FAP:Tb3+,Eu3+ samples exhibit a blue-light emission of the host matrix, as well as the typical green emission band of the Tb3+ ions, and a red-light emission of Eu 3+. The highly intense red emission bands of the Eu3+ ions were attributed to the effective energy transfer from the Tb3+ to Eu3+ ions, which has been justified through the luminescence spectra and the fluorescence decay dynamics. The luminescence colors of FAP:Tb 3+,Eu3+ microrods can be easily tuned by changing the concentration of Eu3+ ions. The results reveal that the combination of the self-activated luminescence and rare earth-doping emission in FAP:Tb 3+,Eu3+ microrods could result in tunable emission in a large color gamut, which can be used as a potential candidate for white-light-emitting diodes and other display devices. © 2014 The Royal Society of Chemistry.

Jin R.,Northeast Normal University | Yang Y.,Northeast Normal University | Xing Y.,Northeast Normal University | Chen L.,Northeast Normal University | And 2 more authors.
ACS Nano | Year: 2014

The hierarchical assembly of multilevel, nonspherical hollow structures remains a considerable challenge. Here, we report a facile approach for synthesizing copper silicate hollow nanofibers with an ultrasmall nanotube-assembled, double-walled structure. The as-prepared hollow fibers possess a tailored complex wall structure, high length-to-diameter ratio, good structural stability, and a high surface area, and they exhibit excellent performance as an easily recycled adsorbent for wastewater treatment and as an ideal support for noble metal catalysts. In addition, this strategy can be extended as a general approach to prepare other double-walled, hollow, fibrous silica-templated materials. © 2014 American Chemical Society.

Nakamura I.,CAS Changchun Institute of Applied Chemistry
Journal of Physical Chemistry C | Year: 2015

We studied ionic liquids confined between charged plates to develop a dipolar self consistent field theory (DSCFT) for incompressible states and a hybrid of DSCFT combined with Monte Carlo simulation for compressible states. Our theory, which has no adjustable parameters, accounts for the differences between the dipole moments and the molecular volumes of the cation and anion, the hard core nature of the ions, and the electrical double layer formed through the strong association of the ions with the electrodes. We illustrate that a spatial change in the distributions of cations and anions with different dipole moments causes a significant spatial change in the dielectric function and hence gives rise to spatial asymmetry in the electrostatic field between the charged plates. Notably, this effect can be comparable to that caused by an asymmetry in the molecular volumes of the cation and anion. Moreover, the hard core nature of ionic liquids causes oscillations in the density profile near the charged plates. We also demonstrate that a contrast in the dielectric values of the cations and anions in ionic liquids causes a substantial decrease in capacitance as the applied voltage is increased. The magnitude of this variation can be noticeably altered by changing the dipole moments of the cation and anion. © 2015 American Chemical Society.

Yang J.,Southwest University | Lin J.,CAS Changchun Institute of Applied Chemistry
Journal of the Electrochemical Society | Year: 2010

Lu2 O3: Yb3+ / Ho3+ phosphors were prepared by a Pechini sol-gel process. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL), cathodoluminescence (CL) spectra, as well as lifetimes were utilized to characterize the synthesized phosphors. XRD and HRTEM results reveal that the samples are obtained with high crystallinity. The FESEM images indicate that Lu2 O3: Yb3+ / Ho3+ phosphors are composed of fine and spherical grains around 50-80 nm in size. Under the excitation of UV light, 980-nm laser, and low-voltage electron beams, all Lu2 O3: Yb3+ / Ho3+ phosphors show the characteristic emission of the Ho3+ ion (F45, S25 → I85 transition) with green luminescence, which is easily observed by our naked eyes. The corresponding luminescent mechanisms have been discussed. Due to the excellent PL (including upconversion and downconversion) properties, CL properties, and cheap materials of the Lu2 O3: Yb3+ / Ho3+ phosphors, the as-prepared phosphors are potentially applied for fluorescent lamps, upconversion fluorescent labels, and field emission display devices. © 2010 The Electrochemical Society.

Liu J.,Xiangtan University | Zhou Y.,Xiangtan University | Wang J.,Xiangtan University | Pan Y.,Xiangtan University | And 2 more authors.
Chemical Communications | Year: 2011

Uniform yolk-shell V 2O 5 microspheres were synthesized via a facile template-free solvothermal route and subsequent calcination treatment in air. The resulting cathode materials showed a high specific capacity of 220 mA h g -1 after 30 cycles and good rate capability. © 2011 The Royal Society of Chemistry.

Sun X.,Oak Ridge National Laboratory | Sun X.,CAS Changchun Institute of Applied Chemistry | Luo H.,Oak Ridge National Laboratory | Dai S.,Oak Ridge National Laboratory | Dai S.,University of Tennessee at Knoxville
Chemical Reviews | Year: 2012

A study was conducted to demonstrate that ionic liquids-based extraction had emerged as a potential strategy for the advanced nuclear fuel cycle (NFC). The advanced NFC maximized fuel resource utilization, reduced the volume and toxicity of nuclear waste, facilitated handling and transportation, and saved on geological repository costs. Room-temperature ionic liquids (ILs), a novel type of solvent, showed significant potential as a separation technology for the advanced NFC. Room-temperature ionic liquids were defined as room-temperature molten salts, which were composed of cations and anions, and their melting points were below 100 °C. The ILs gained significance for their preparation, purification, physicochemical properties, solvation environment, partitioning behavior, and extraction mechanism, along with strategies for improvement and a forecast of IL-based extraction from the viewpoint of promising technologies for the advanced NFC.

Lai Z.,State University of New York at Stony Brook | Preketes N.K.,University of California at Irvine | Mukamel S.,University of California at Irvine | Wang J.,State University of New York at Stony Brook | Wang J.,CAS Changchun Institute of Applied Chemistry
Journal of Physical Chemistry B | Year: 2013

Protein folding is one of the most fundamental problems in modern molecular biology. Uncovering the detailed folding mechanism requires methods that can monitor the structures at high temporal and spatial resolution. Two-dimensional infrared (2DIR) spectroscopy is a new tool for studying protein structures and dynamics with high time resolution. Using atomistic molecular dynamics simulations, we illustrate the folding process of Trp-cage along the dominant pathway on the free energy landscape by analyzing nonchiral and chiral coherent 2DIR spectra along the pathway. Isotope labeling is used to reveal residue-specific information. We show that the high resolution structural sensitivity of 2DIR can differentiate the ensemble evolution of protein and thus provides a microscopic picture of the folding process. © 2013 American Chemical Society.

Redweik S.,TU Braunschweig | Xu Y.,TU Braunschweig | Xu Y.,CAS Changchun Institute of Applied Chemistry | Watzig H.,TU Braunschweig
Electrophoresis | Year: 2012

A generic screening approach was performed to investigate the binding of various potential ligands to proteins in order to investigate how proteins interact with ions and the complete surrounding solution. This also allows to study binding behavior and its regulation and protein functionality in general in a native environment. The ACE technique affords an excellent precision by applying appropriate rinsing procedures using a pressure of 2.5 bar and a continuous flow concept. Confidence intervals were estimated to proof significance of the interactions. This enables to investigate smaller yet important interactions, which were not possible with less precise techniques before. The influence of various ions on ovalbumin, β-lactoglobulin, and BSA were screened by comparing the mobility ratios of the free protein and the influenced one. The analysis was performed using the metal ions Ba2+, Ca2+, Cu2+, Mg2+, Mn2+, Ni2+, the pharmaceutical cations ephedrine hydrochloride, ethambutol dihydrochloride, pilocarpine hydrochloride and pirenzepine dihydrochloride, and various anions, in particular phosphate, acetate, succinate, glutamate, and salicylate. For the anion influence study, myoglobin was also included to the screened proteins. The influence of these ions on the proteins was well diversified. The interactions could be distinguished with a fast and precise screening method since 90% of all mobility ratios had a RSD% below 2% and 79% had a RSD% lower than 1%. Hence, for more than 75% of the protein-ligand pairs significant interactions are observed with a very small confidence interval due to the very excellent precision of these used method. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Han J.,Drexel University | Lazarovici P.,Drexel University | Pomerantz C.,Drexel University | Chen X.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Biomacromolecules | Year: 2011

In search for novel biomimetic scaffolds for application in vascular tissue engineering, we evaluated a series of fibrous scaffolds prepared by coelectrospinning tertiary blends of poly(lactide-co-glycolide) (PLGA), gelatin, and elastin (PGE). By systematically varying the ratios of PLGA and gelatin, we could fine-tune fiber size and swelling upon hydration as well as the mechanical properties of the scaffolds. Of all PGE blends tested, PGE321 (PLGA, gelatin, elastin v/v/v ratios of 3:2:1) produced the smallest fiber size (317 ± 46 nm, 446 ± 69 nm once hydrated) and exhibited the highest Youngs modulus (770 ± 131 kPa) and tensile strength (130 ± 7 kPa). All PGE scaffolds supported the attachment and metabolization of human endothelial cells (ECs) and bovine aortic smooth muscle cells (SMCs) with some variances in EC morphology and cytoskeletal spreading observed at 48 h postseeding, whereas no morphologic differences were observed at confluence (day 8). The rate of metabolization of ECs, but not of SMCs, was lower than that on tissue culture plastic and depended on the specific PGE composition. Importantly, PGE scaffolds were capable of guiding the organotypic distribution of ECs and SMCs on and within the scaffolds, respectively. Moreover, the EC monolayer generated on the PGE scaffold surface was nonthrombogenic and functional, as assessed by the basal and cytokine-inducible levels of mRNA expression and amidolytic activity of tissue factor, a key player in the extrinsic clotting cascade. Taken together, our data indicate the potential application of PGE scaffolds in vascular tissue engineering. © 2010 American Chemical Society.

Guo N.,University of Shanghai for Science and Technology | You H.,CAS Changchun Institute of Applied Chemistry | Jia C.,University of Shanghai for Science and Technology | Ouyang R.,University of Shanghai for Science and Technology | Wu D.,University of Shanghai for Science and Technology
Dalton Transactions | Year: 2014

In this study, we synthesized and characterized a series of Eu2+ and Mn2+-coactivated fluoro-apatite-structure Ca6Y 2Na2(PO4)6F2 phosphors, which can provide high-quality standard white emission from a single-phase host. The powder X-ray diffraction, photoluminescence spectra, fluorescence decay curves, chromaticity coordinates, and correlated color temperature of the obtained phosphors were measured and are discussed in detail. Energy transfer from the Eu2+ to the Mn2+ ions was demonstrated by the overlap between the emission spectrum of the Eu2+ ions and the excitation spectrum of the Mn2+ ions, and the systematic relative decline and growth of the emission bands of Eu2+ and Mn2+, respectively. A possible energy transfer mechanism was proposed based on the experimental results and analysis. It was discovered that the emission colors of the phosphor varied from blue through white and eventually to yellow by properly tuning the doping content of Mn2+ with a fixed Eu 2+ content through the principle of energy transfer. The developed phosphors can be efficiently excited in the UV region and exhibit white-light emission, making them attractive as white-emitting conversion phosphors for UV-based white light emitting diodes. © 2014 the Partner Organisations.

Wang L.,Jiangxi Normal University | Zheng Y.,Jiangxi Normal University | Lu X.,Jiangxi Normal University | Li Z.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Sensors and Actuators, B: Chemical | Year: 2014

A novel nonenzymatic glucose sensor was developed by electrodepositing dendritic copper-cobalt nanostructures (Cu-Co NSs) on glassy carbon electrode (GCE) which was modified by reduced grapheme oxide-chitosan (RGO-CHIT) nanocomposites. The electrochemical behaviors and electrocatalytic performances of the sensor towards oxidation of glucose were evaluated by cyclic voltammograms, chronoamperometry and amperometric method. Compared to sensors based on monometal Cu or Co NSs, the sensor based on bimetal Cu-Co NSs exhibits good electrocatalytic activity towards oxidation of glucose. The effects of electrodeposition time and the ratio of Cu2+ and Co2+ in an electrodeposition solution on the electrocatalytic performance of the Cu-Co NSs sensor were explored in detail. The best catalytic activity towards oxidation of glucose can be achieved under an optimized condition: electrodepositing time of 2600 s and the Cu2+/Co2+ molar ratio of 2:1. The catalytic current density is linear to the glucose concentration in the range of 0.015-6.95 mM (r = 0.9947) with a sensitivity of 1921 μA cm-2 mM-1, and a detection limit of 10 μM. The good catalytic activity, high sensitivity and good stability indicate that the newly developed sensor based on the dendritic Cu-Co NSs/RGO-CHIT/GCE is a promising sensor for application in real samples. © 2014 Elsevier B.V.

Zan X.,University of South Carolina | Feng S.,University of South Carolina | Balizan E.,University of South Carolina | Lin Y.,CAS Changchun Institute of Applied Chemistry | Wang Q.,University of South Carolina
ACS Nano | Year: 2013

A facile and robust method to align one-dimensional (1D) nanoparticles (NPs) in large scale has been developed. Using flow assembly, representative rod-like nanoparticles, including tobacco mosaic virus (TMV), gold nanorods, and bacteriophage M13, have been aligned inside glass tubes by controlling flow rate and substrate surface properties. The properties of 1D NPs, such as stiffness and aspect ratio, play a critical role in the alignment. Furthermore, these hierarchically organized structures can be used to support cell growth and control the cell orientation and morphology. When C2C12 myoblasts were cultured on surfaces coated with aligned TMV, we found that nanoscale topographic features were critical to guide the cell orientation and myogenic differentiation. This method can therefore be used in the fabrication of complex assemblies with 1D NPs and have wide applications in tissue engineering, sensing, electronics, and optical fields. © 2013 American Chemical Society.

Li D.,Jilin University | Liang Z.,Jilin University | Chen J.,CAS Changchun Institute of Applied Chemistry | Yu J.,Jilin University | Xu R.,Jilin University
Dalton Transactions | Year: 2013

A new type of organophosphonic acid, (4,4′-(1,2-diphenylethene-1,2- diyl)bis(4,1-phenylene))bis(methylene)diphosphonic acid (PATPE), based on tetraphenylethene has been prepared, and its ester derivative exhibits the characteristic property of aggregation-induced emission (AIE) in DMSO-H 2O solution. The PATPE is then fabricated into hydroxyapatite by a one-pot condensation process to form hollow mesoporous nanocapsules of ellipsoidal morphology. The AIE luminogen-bridged hollow hydroxyapatite nanocapsules emit strong blue light under UV irradiation, which is further used for drug delivery using ibuprofen (IBU) as a model drug. The fluorescence intensity of the materials varies greatly with the loading and release of IBU, suggesting that the drug release process may be tracked in terms of the change of luminescence intensity. The biocompatibility of AIE luminogen functionalized material is also evaluated on HUH7 human hepatoma cells using the MTT assay. The low cytotoxicity of the materials reveals that the as-prepared multifunctional hydroxyapatite will be a new candidate for simultaneous drug delivery and cell imaging in potential bioapplications. This journal is © The Royal Society of Chemistry 2013.

Su Z.,CAS Changchun Institute of Applied Chemistry | Wang Q.,University of South Carolina
Angewandte Chemie - International Edition | Year: 2010

Re-engineer the core: The genomic core of a virus (left) can be re-engineered by the coassembly of viral coat proteins and DNA amphiphiles to produce virus-like nanocarriers to transport both hydrophobic and hydrophilic compounds. It is a general strategy for adapting virus-based vehicles for drug-delivery applications. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Choi W.H.,Hong Kong Baptist University | Tam H.L.,Hong Kong Baptist University | Ma D.,CAS Changchun Institute of Applied Chemistry | Zhu F.,Hong Kong Baptist University
Optics Express | Year: 2015

White organic light-emitting diodes (WOLEDs) resemble light more naturally, with emission spectrum that is comfortable to the human eye. The transparent WOLEDs can be almost invisible by day and can emit a pleasant diffused light at night, allowing the surface light source to shine in both directions, an exciting new lighting technology that could bring new device concepts. However, undesirable angular-dependent emission in transparent WOLEDs is often observed, due to the microcavity effect. In this work, the emission behavior of dual-side emissive transparent WOLEDs was studied experimentally and theoretically. It is found that avoidance of the overlap between the peak wavelengths of the emitters and the resonant wavelength of the organic microcavity moderates the angulardependent electroluminescence emission behavior, thereby improving the color stability of the transparent white WOLEDs over a broad range of the viewing angle. © 2015 Optical Society of America.

Li C.,State University of New York at Stony Brook | Wang J.,State University of New York at Stony Brook | Wang J.,CAS Changchun Institute of Applied Chemistry
Proceedings of the National Academy of Sciences of the United States of America | Year: 2014

Cell cycles, essential for biological function, have been investigated extensively. However, enabling a global understanding and defining a physical quantification of the stability and function of the cell cycle remains challenging. Based upon a mammalian cell cycle gene network, we uncovered the underlying Mexican hat landscape of the cell cycle. We found the emergence of three local basins of attraction and two major potential barriers along the cell cycle trajectory. The three local basins of attraction characterize the G1, S/G2, and M phases. The barriers characterize the G1 and S/G2 checkpoints, respectively, of the cell cycle, thus providing an explanation of the checkpoint mechanism for the cell cycle from the physical perspective. We found that the progression of a cell cycle is determined by two driving forces: curl flux for acceleration and potential barriers for deceleration along the cycle path. Therefore, the cell cycle can be promoted (suppressed), either by enhancing (suppressing) the flux (representing the energy input) or by lowering (increasing) the barrier along the cell cycle path. We found that both the entropy production rate and energy per cell cycle increase as the growth factor increases. This reflects that cell growth and division are driven by energy or nutrition supply. More energy input increases flux and decreases barrier along the cell cycle path, leading to faster oscillations. We also identified certain key genes and regulations for stability and progression of the cell cycle. Some of these findings were evidenced from experiments whereas others lead to predictions and potential anticancer strategies.

Li W.,Jilin University | Pan Y.,Jilin University | Xiao R.,Jilin University | Peng Q.,Jilin University | And 7 more authors.
Advanced Functional Materials | Year: 2014

In principle, the ratio (Φ) of the maximum quantum efficiencies for electroluminescence (EL) to photoluminescence (PL) can be expected to approach unity, if the exciton (bound electron-hole pair) generated from the recombination of injected electrons and holes in OLEDs has a sufficiently weak binding energy. However, seldom are examples of Φ > 25% reported in OLEDs because of the strongly bound excitons for most organic semiconductors in nature. Here, a twisting donor-acceptor triphenylamine-thiadiazol molecule (TPA-NZP) exhibits fluorescent emission through a hybridized local and charge-transfer excited state (HLCT), which is demonstrated from both fluorescent solvatochromic experiment and quantum chemical calculations. The HLCT state possesses two combined and compatible characteristics: a large transition moment from a local excited (LE) state and a weakly bound exciton from a charge transfer (CT) state. The former contributes to a high-efficiency radiation of fluorescence, while the latter is responsible for the generation of a high fraction of singlet excitons. Using TPA-NZP as the light-emitting layer in an OLED, high Φ values of 93% (at low brightness) and 50% (at high brightness) are achieved, reflecting sufficient employment of the excitons in the OLED. Characterization of the EL device shows a saturated deep-red emission with CIE coordinates of (0.67, 0.32), accompanied by a rather excellent performance with a maximum luminance of 4574 cd m-2 and a maximum external quantum efficiency (ηext) of ∼2.8%. The HLCT state is a new way to realize high-efficiency of EL devices. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Qian G.,Carleton University | Abu H.,Carleton University | Wang Z.Y.,Carleton University | Wang Z.Y.,CAS Changchun Institute of Applied Chemistry
Journal of Materials Chemistry | Year: 2011

A precursor strategy for the synthesis and screening of a series of conjugated donor-acceptor polymers is demonstrated by successful preparation of low band-gap polymers (P2-P5) containing triphenylamine as an electron donor and several heterocycles as acceptors, such as [1,2,5]thiadiazolo[3,4-g] quinoxaline, [1,2,5]thiadiazolo[3,4-i]dibenzo[a,c]phenazine, benzo[1,2-c:4,5-c′]bis([1,2,5]thiadiazole), and selenadiazole[3,4-f] benzo[c][1,2,5]thiadiazole, that are transformed from a single reactive polymer (P1). Polymers P2-P5 have the band gap of 1.71-1.29 eV and show the absorption and emission in the near infrared (NIR) spectral region. All the polymers are also NIR electrochromic. In particular, polymer P3 is electrochemically switchable between leaf-like green coloring and near-infrared absorbing states with an efficiency of 479 cm2 C-1 at 1310 nm or 232 cm2 C-1 at 1550 nm, making it potentially useful for electrically switchable day-to-night camouflage applications. © 2011 The Royal Society of Chemistry.

Nakamura I.,CAS Changchun Institute of Applied Chemistry
Journal of Physical Chemistry B | Year: 2014

We studied the thermodynamic properties of ion solvation in polymer blends and block copolymer melts and developed a dipolar self-consistent field theory for polymer mixtures. Our theory accounts for the chain connectivity of polymerized monomers, the compressibility of the liquid mixtures under electrostriction, the permanent and induced dipole moments of monomers, and the resultant dielectric contrast among species. In our coarse-grained model, dipoles are attached to the monomers and allowed to rotate freely in response to electrostatic fields. We demonstrate that a strong electrostatic field near an ion reorganizes dipolar monomers, resulting in nonmonotonic changes in the volume fraction profile and the dielectric function of the polymers with respect to those of simple liquid mixtures. For the parameter sets used, the spatial variations near an ion can be in the range of 1 nm or larger, producing significant differences in the solvation energy among simple liquid mixtures, polymer blends, and block copolymers. The solvation energy of an ion depends substantially on the chain length in block copolymers; thus, our theory predicts the preferential solvation of ions arising from differences in chain length. © 2014 American Chemical Society.

Shang L.,Karlsruhe Institute of Technology | Dong S.,CAS Changchun Institute of Applied Chemistry | Nienhaus G.U.,Karlsruhe Institute of Technology | Nienhaus G.U.,University of Illinois at Urbana - Champaign
Nano Today | Year: 2011

Recent advances in nanotechnology have given rise to a new class of fluorescent labels, fluorescent metal nanoclusters, e.g., Au and Ag. These nanoclusters are of significant interest because they provide the missing link between atomic and nanoparticle behavior in metals. Composed of a few to a hundred atoms, their sizes are comparable to the Fermi wavelength of electrons, resulting in molecule-like properties including discrete electronic states and size-dependent fluorescence. Fluorescent metal nanoclusters have an attractive set of features, such as ultrasmall size, good biocompatibility and excellent photostability, making them ideal fluorescent labels for biological applications. In this review, we summarize synthesis strategies of water-soluble fluorescent metal nanoclusters and their optical properties, highlight recent advances in their application for ultrasensitive biological detection and fluorescent biological imaging, and finally discuss current challenges for their potential biomedical applications. © 2011 Elsevier Ltd. All rights reserved.

Shen R.,Chinese Academy of Sciences | Shen X.,Chinese Academy of Sciences | Zhang Z.,Anhui University of Science and Technology | Li Y.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Journal of the American Chemical Society | Year: 2010

We used a click reaction to synthesize a bidentate 1,2,3-triazole-based ligand, TA, for use in the preparation of aqueous CdS quantum dots (QDs). TA-conjugated CdS QDs exhibited two fluorescence emission peaks, one at 540 nm arising from CdS nanocrystals and the other at ∼670 nm arising from TA-CdS QD complexes formed via surface coordination. Coordination between TA and CdS was verified by using X-ray photoelectron (N 1s) spectra as well as Raman and NMR spectra of TA-capped QDs. Electrochemical analysis revealed that the 1,2,3-triazole moities in TA form complexes with the Cd(II) ions. The aqueous QDs protected by TA were very stable at different ionic strengths and over a broad pH range, according to fluorescence analysis. The ethidium bromide exclusion assay demonstrated that the bidentate TA ligand interacts strongly with DNA. Fluorescent micrographs and TEM images of cancer cells stained with TA-capped QDs clearly showed that the TA ligand targeted CdS QDs to the nucleoli of cells. In contrast, thioglycolic acid-capped CdS QDs just stained the cell membranes and could not pass the cell membranes to reach the cell nucleus. © 2010 American Chemical Society.

Pang X.,Cornell University | Pang X.,CAS Changchun Institute of Applied Chemistry | Chu C.-C.,Cornell University
Polymer | Year: 2010

A series of new biodegradable hybrid hydrogels were designed and fabricated from a new family of amino acid-based functional poly(ester amide) (PEA-AG) and commercial poly(ethylene glycol) diacrylate (PEG-DA) or Pluronic diacrylate (Pluronic-DA) by UV photocrosslinking. These biodegradable hybrid hydrogels were characterized in terms of equilibrium swelling ratio (Qeq), compression modulus by dynamic mechanical analysis (DMA), and interior morphology by scanning electron microscope (SEM). Both the precursors' chemical structures and feed ratio had significant effect on the properties of the hybrid hydrogels. All these hybrid hydrogels had a three-dimensional porous network structure. The hydrophobicity, crosslinking density and mechanical strength of the hybrid hydrogels increased with an increase in allylglycine (AG) content in the PEA-AG, but the swelling and pore size of the hybrid hydrogels decreased. The biodegradation rate of these hybrid hydrogels in an enzyme (α-chymotrypsin) solution was faster than in a pure PBS buffer control, and the biodegradation rate increased with an increase in α-chymotrypsin concentration and allylglycine content. © 2010.

Qin C.,Hong Kong Baptist University | Wong W.-Y.,Hong Kong Baptist University | Wang L.,CAS Changchun Institute of Applied Chemistry
Macromolecules | Year: 2011

A water-soluble organometallic conjugated polyelectrolyte P1 and its corresponding model complex M1 based on an aspartic acid-substituted fluorene spacer are reported, which possess good water solubility as well as intriguing fluorescent and phosphorescent dual-emissive properties in a completely organic-free aqueous medium at room temperature. A new colorimetric silver ion sensor based on P1 is developed, which shows high selectivity and sensitivity for Ag+ ions in buffered water solution because of the Ag +-induced intersystem crossing from the singlet to triplet states. The obvious color change from colorless to yellow upon exposure to Ag + ion is visible to the naked eyes and can be quantified colorimetrically by the visible absorption spectroscopic method. On the basis of the fluorescence intensity of P1 obtained in the fluorescence titration curves, a linear relationship is observed in the Stern-Volmer plot at low concentrations (1-5μM), and the corresponding Stern-Volmer quenching constant (KSV) of 1.9 × 105 M-1 for P1 is comparable to that obtained from the fluorescence titration studies. As determined by the Benesi-Hildebrand plot obtained from the absorption spectra, a 1:1 complex formation is anticipated between the Pt compound and Ag+ ion. The limit of detection is low at 0.5 μM, i.e., at concentrations in the ppb range. The present study represents an original approach using a water-soluble organometallic conjugated polyelectrolyte for the accurate and rapid detection of trace amounts of Ag+ ion in pure water. It also establishes a new system featuring dual-emissive properties of platinum(II) acetylide-based conjugated polymers for chemosensing application. © 2010 American Chemical Society.

Zhang N.,CAS Changchun Institute of Applied Chemistry | Salzinger S.,TU Munich | Soller B.S.,TU Munich | Rieger B.,TU Munich
Journal of the American Chemical Society | Year: 2013

Poly(2-isopropenyl-2-oxazoline) (PIPOx) and poly(2-vinylpyridine) (P2VP) have been efficiently synthesized using bis(cyclopentadienyl)methylytterbium (Cp2YbMe) as catalyst. The polymerizations of 2-isopropenyl-2- oxazoline (IPOx) and 2-vinylpyridine (2VP) follow a living group-transfer polymerization (GTP) mechanism, allowing a precise molecular-weight control of both polymers with very narrow molecular-weight distribution. The GTP of IPOx and 2VP occurs via N coordination at the rare earth metal center, which has rarely been reported previously. The relative coordination strength of different monomers at the ytterbium center is determined by copolymerization investigations to be in the order of DEVP > MMA > IPOx > 2VP. In combination with living cationic ring-opening polymerization, PIPOx is converted to molecular brushes with defined backbone and poly(2-oxazoline) side chains using the grafting-from method. © 2013 American Chemical Society.

Hu J.,Anhui University of Science and Technology | Zhang G.,Anhui University of Science and Technology | Geng Y.,CAS Changchun Institute of Applied Chemistry | Liu S.,Anhui University of Science and Technology
Macromolecules | Year: 2011

We report on the fabrication of a novel type of ratiometric fluorescent polymeric probes for fluoride ions (F-) based on self-assembled micellar nanoparticles of P(MMA-co-NBDAE)-b-PF-b-P(MMA-co-NBDAE) coil-rod-coil triblock copolymer, where MMA, NBDAE, and PF are methyl methacrylate, 4-(2-acryloyloxyethylamino)-7-nitro-2,1,3-benzoxadiazole, and polyfluorene, respectively. Blue-emitting conjugated PF block and green-emitting NBDAE moieties with F- turn-off characteristics within the PMMA block serve as fluorescence resonance energy transfer (FRET) donors and switchable acceptors, respectively. For coil-rod-coil triblock copolymer in a good solvent such as THF, the blue emission of PF block dominates due to unimolecularly dissolved state associated with ineffective FRET process. The addition of F - ions only leads to ∼2.92-fold decrease of fluorescence intensity ratio, I515/I417, of characteristic NBDAE and PF emission bands. In acetone, the triblock copolymer spontaneously self-assembles into micelles possessing PF cores and NBDAE-labeled PMMA coronas. In the absence of F- ions, effective FRET processes between micellar cores and coronas occurs, resulting in prominently enhanced NBDAE emission. Upon addition of F- ions, the quenching of NBDAE emission bands leads to ∼8.75-fold decrease in the emission intensity ratio, I515/I 417, which is also accompanied by naked eye-discernible fluorometric transition from cyan to blue emissions and colorimetric transition from green to yellowish. At a micellar concentration of 0.1 g/L in acetone at 25 °C, the detection limit of F- ions can be down to ∼4.78 μM (∼0.09 ppm). This work presents a new example of polymeric micelles-based optical F- probes and manifests that, upon proper structural design and optimization of spatial distribution of FRET donors and acceptors, self-assembled micelles of coil-rod-coil triblock copolymers serve as better ratiometric fluorescent F- ion sensors possessing visual detection capability, as compared to that of molecularly dissolved chains. © 2011 American Chemical Society.

Soller B.S.,TU Munich | Zhang N.,CAS Changchun Institute of Applied Chemistry | Rieger B.,TU Munich
Macromolecular Chemistry and Physics | Year: 2014

Recent studies have shown that rare earth metal-mediated group transfer polymerization (REM-GTP) can be applied to a variety of polar monomers, besides the classic (meth)acrylates or (meth)acrylamides, giving access to new polymeric materials. This article highlights progress in this new field and gives a current overview of the initiation and propagation of vinylphosphonates, the extension to Michael-type nitrogen-coordinating monomers, and application to block copolymers, statistical copolymers, and 2D and 3D structures. Based on molecular understanding and high-precision synthesis, REM-GTP represents a versatile method for the preparation of new materials. Rare earth metal-mediated group transfer polymerization (REM-GTP) is an elegant method to obtain materials from polar monomers. REM-GTP is being applied to phosphorous- and nitrogen-containing monomers, extending this catalytic polymerization to new materials. In this review, an overview is given about the high-precision synthesis of homopolymers, block copolymers, and molecular brushes using lanthanide complexes. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aoki K.,Toyohashi University of Technology | Fujisawa I.,Toyohashi University of Technology | Murayama K.,Tohoku University | Hu N.-H.,CAS Changchun Institute of Applied Chemistry
Coordination Chemistry Reviews | Year: 2013

Metal ions play a key role in nucleic acid structure and activity. The elucidation of factors/rules that govern the binding of metal ions is therefore an essential step for the better understanding of nucleic acid functions. In this review, we deal with stereospecific intra-molecular interligand interactions as such a factor, involving hydrogen-bonding, electrostatic interaction, and steric constraints, especially focusing on their significance as a factor that could affect base-specific metal bonding to adenine and guanine bases in the solid state. © 2013 Elsevier B.V.

Shang X.,Changchun University of Technology | Han D.,Changchun University of Science and Technology | Li D.,Changchun University of Technology | Wu Z.,CAS Changchun Institute of Applied Chemistry
Chemical Physics Letters | Year: 2013

We report a quantum-chemistry analysis of four heteroleptic iridium(III) complexes (tfmppy)2Ir(tpip) [tfmppy = 4- trifluoromethylphenylpyridine, tpip = tetraphenylimido-diphosphinate] (1), (tfmpyN3)2Ir(tpip) [tfmpyN3 = 4-trifluoromethylphenyl-[1,2,3]-triazole] (2), (CN-pyN3) 2Ir(tpip) [CN-pyN3 = 4-cyanophenyl-[1,2,3]-triazole] (3) (ph-pta)2Ir(tpip) [ph-pta = 2-(5-phenyl-[1,2,4]-triazol-3-yl)- pyridine] (4), which have been studied by using density functional theory (DFT) and time-dependent DFT (TDDFT) methods, to investigate their electronic structures, injection and transport properties, absorption and phosphorescence mechanism. The results reveal the different cyclometalated ligands have a large impact on the charge transfer performances of the studied complexes. The complex 4 possess better charge transfer abilities and balanced charge transfer rates, which is a potential candidate as blue-emitting material. © 2013 Elsevier B.V. All rights reserved.

Ghosh K.R.,Carleton University | Saha S.K.,Carleton University | Gao J.P.,Carleton University | Wang Z.Y.,Carleton University | Wang Z.Y.,CAS Changchun Institute of Applied Chemistry
Chemical Communications | Year: 2014

A fluorescence sensory polymer containing the pentiptycene and tetraphenylethylene units linked by acetylene was synthesized for direct detection of isocyanates in air. Eight industrially available aliphatic and aromatic isocyanates were tested. The polymer film shows a rapid fluorescence quenching response to any type of isocyanates with a ppt level of detection limit, which is much lower than the permissible exposure limit of 5 ppb. © 2014 The Royal Society of Chemistry.

Wu H.,Kyushu University | Su Z.,CAS Changchun Institute of Applied Chemistry | Takahara A.,Kyushu University
Soft Matter | Year: 2011

We report formation of nanorods that exhibit a gradient distribution of poly(2,6-dimethylphenylene oxide) and polystyrene (PPO and PS), i.e., the PPO weight fractions in the nanorods increase from top to bottom along the long axis of the nanorods. PPO/PS nanorods with various diameters were prepared by infiltrating porous anodic aluminium oxide (AAO) templates with polymer blend melts. Their morphology was investigated by Fourier transform infrared spectroscopy (FTIR). The gradient distribution of polymer blends in the nanopores is governed by (1) the viscosity difference between the two polymers and (2) the pore diameter. This remains true although PPO/PS blends are compatible in the segmental level. For various diameter nanorods made of PPO/PS blends, the PPO content decreased as the rod diameter became smaller owing to the increased confinement imposed by the nanopores. This leads to a higher rate of capillary rise in smaller nanopores. © 2011 The Royal Society of Chemistry.

Jin Y.,CAS Changchun Institute of Applied Chemistry
Accounts of Chemical Research | Year: 2014

Gold nanoshells (AuNSs) with tunable localized surface plasmon resonance (LSPR) peaks in the near-infrared (NIR) region possess unique optical properties - particularly that soft tissues are "transparent" at these wavelengths - making them of great interest in cancer diagnosis and treatment. Since 1998 when Halas and co-workers invented the first generation of AuNS, with a silica core and Au shell, researchers have studied and designed AuNSs for theranostic - individualized, combination diagnosis and therapy - nanomedicine. As demand has increased for more powerful and practical theranostic applications, so has demand for the next generation of AuNSs - compact yet complex multifunctional AuNSs with finely integrated plasmonic and nonplasmonic inorganic components.For in vivo biomedical applications, such a hybrid AuNS offers the desirable optical properties of NIR LSPR. Size, however, has proved a more challenging parameter to control in hybrid AuNSs. The ideal size of therapeutic NPs is 10-100 nm. Larger particles have limited diffusion in the extracellular space, while particles less than 5 nm are rapidly cleared from the circulation through extravasation or renal clearance. Conventional methods of preparing AuNS have failed to obtain small-sized hybrid AuNSs with NIR LSPR responses.In this Account, we present a new class of multifunctional hybrid AuNSs with ultrathin AuNSs and varied, functional (nonplasmonic) core components ranging from "hard" semiconductor quantum dots (QDs), to superparamagnetic NPs, to "soft" liposomes made using poly-l-histidine as a template to direct Au deposition. The resultant hybrid AuNSs are uniform and compact (typically 15-60 nm) but also preserve the optical properties and shell-type NIR response necessary for biomedical use. We also demonstrate these particles' innovative plasmonic applications in biosensing, multimodal imaging and controlled release. More importantly, the magnetic-plasmonic Fe3O 4/Au core-shell NP enables a new biological imaging method - magnetomotive photoacoustic (mmPA) imaging, which suppresses the nonmagnetomotive background and therefore offers remarkable contrast enhancement and improved specificity compared with photoacoustic images using conventional NP contrast agents.The advantages of our AuNSs are obvious: they are monodisperse, small (<100 nm), highly integrated, and have tunable visible-NIR plasmonic responses. All of these properties are crucial for in vitro or in vivo biological/biomedical studies and many applications, especially for studies of single cells or molecules which require particle monodispersity and tight size control. The plasmonic fluorescent QD/Au and the magnetic plasmonic Fe3O4/Au core-shell NPs may also reveal new physical phenomena that may lead to useful applications, owing to their well-defined core-shell nanoarchitectures and underlying nanoscale physical interactions. © 2013 American Chemical Society.

Wang Z.,CAS Changchun Institute of Applied Chemistry | Hu Z.,CAS Ningbo Institute of Material Technology and Engineering | He T.,Soochow University of China
Journal of Physical Chemistry B | Year: 2010

Single crystals of poly(3-hexylthiophene) (P3HT) and poly(3-octylthiophene) (P3OT) have been prepared by tetrahydrofuran vapor annealing and controlling solvent evaporation, respectively. The morphology and structure of the single crystals are characterized using optical microscopy, scanning electron microscopy, atomic force microscopy, transmission electron microscopy, and wide-angle X-ray diffraction. It is observed that in P3HT single crystals, the molecules are packed with - stacking direction perpendicular to the length axis of the crystals and main chains parallel to the substrate, whereas in P3OT single crystals, the molecules are packed with - stacking direction parallel to the length axis of the crystal and main chains parallel to the substrate. In the field effect transistors, the current flow is parallel to the length axis of the single crystals, and the mobility is 1.57 × 10-3 cm 2/Vs for a P3HT single crystal and 0.62 cm2/Vs for a P3OT single crystal. The single crystals of P3HT and P3OT showed high anisotropic electrical properties. The influences of molecular conformation and alkyl chain length on the electrical properties of P3ATs are discussed. © 2010 American Chemical Society.

Liu C.-G.,Northeast Dianli University | Liu C.-G.,Northeast Normal University | Liu C.-G.,CAS Changchun Institute of Applied Chemistry | Guan X.-H.,Northeast Dianli University
Journal of Physical Chemistry C | Year: 2013

The electronic structure and second-order nonlinear optical (NLO) property of a series of monoruthenium-substituted Keggin-type polyoxometalates (POMs) have been studied by using density functional theory (DFT) and time-dependent (TD)DFT calculations. The DFT calculation supports that these POM complexes possess donor-π-conjugated bridge-acceptor (D-π-A) structure, which the ruthenium atom acts as the role of electron donor and the three vanadium atoms in cap region of Keggin-type POM act as the role of electron acceptor. It is well-known that D-π-A structure, as a simple molecular scheme, has been successfully used in the development of organic NLO materials. However, the totally inorganic molecule having D-π-A structure is very rare. Thereby the second-order NLO properties of these POM complexes have been analyzed in this work. According to the calculations, introduction of the electron acceptor leads to a substantial enhancement on the second-order NLO response. The calculated βHRS(-2ω; ω, ω) value of three-vanadium-atom derivative [{PW9V3O39}RuII(H 2O)]8- is 34 times as large as that of [{PW 11O39}RuII(H2O)]5- according to CAM-B3LYP/6-31+g* calculations (Lanl2dz basis sets for metal atom) in acetonitrile. Because of the redox-active ruthenium center and large second-order NLO response, the redox switching of second-order NLO responses for the three-vanadium-atom derivative [{PW9V3O 39}RuII(H2O)]8- also have been studied. The results show that the RuII→RuIII oxidation leads to the first hyperpolarizability to decrease remarkably. © 2013 American Chemical Society.

Lin Y.,CAS Changchun Institute of Applied Chemistry | Wang Q.,University of South Carolina
Angewandte Chemie - International Edition | Year: 2012

K(l)ick it into reverse: Mechanical force (ultrasound) may be employed to promote a retrocycloaddition reaction of a 1,2,3-triazole to regenerate the parent azide and alkyne, a reaction that cannot be achieved by other means. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Zhang M.,Zhejiang University | Xu D.,CAS Changchun Institute of Applied Chemistry | Yan X.,Zhejiang University | Chen J.,Zhejiang University | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2012

Automatic repair: A polymer with pendent dibenzo[24]crown-8 units (purple in picture) was cross-linked by two bisammonium salts (green) to form two supramolecular gels based on host-guest interactions. These two gels are stimuli-responsive materials that respond to changes of the pH value and are also self-healing materials, as can be seen by eye and as evidenced by rheological data. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Shih Z.-Y.,National Taiwan University | Wang C.-W.,National Taiwan University | Xu G.,CAS Changchun Institute of Applied Chemistry | Chang H.-T.,National Taiwan University
Journal of Materials Chemistry A | Year: 2013

A facile method has been demonstrated for the preparation of PdCu nanoparticles (NPs) with various morphologies from Pd2+ and Cu 2+ reduced by ascorbate in the presence of dodecyltrimethylammonium chloride (DTAC) at 95 °C. We have found that DTAC is important to assist the growth of PdCu with high-energy surfaces through the etching and capping of certain surfaces of Pd and PdCu seeds. By varying the Pd2+/Cu 2+ molar ratio, different morphologies of PdCu NPs have been prepared. Cubic PdCu NPs have a dominant Pd3Cu composition when prepared at a high Pd2+/Cu2+ molar ratio (20/1), while porous PdCu NPs have a dominant PdCu3 composition when prepared at a low Pd2+/Cu2+ molar ratio (1/10). The copper content not only controls the morphology, but also affects the catalytic activity toward the methanol oxidation reaction (MOR) in alkaline media. Upon increasing the copper content, the catalytic activity toward the MOR increases, mainly due to the advantages of the electroactive surface area, more direct cathodic oxide reduction (lower onset potential for the formation of Pd-OH), and synergistic effects. Porous PdCu NP-modified electrodes provide a higher catalytic activity (363 A g-1) toward the MOR at a more negative onset potential (-0.62 V vs. Ag/AgCl) on the porous PdCu electrodes than commercial Pd/C-modified ones do (180 A g-1) at -0.52 V. To the best of our knowledge, this is the first example using porous PdCu NP-modified electrodes as anodes under alkaline conditions in direct methanol fuel cells (DMFCs). With the advantages of high electrochemical activity, stability, and cost effectiveness, the porous PdCu NPs have great potential as anode catalysts for DMFCs. © The Royal Society of Chemistry 2013.

Zhang J.,Jilin University | Lu Z.-Y.,Jilin University | Sun Z.-Y.,CAS Changchun Institute of Applied Chemistry
Soft Matter | Year: 2013

We study the influence of solvent conditions and the chain backbone stiffness of an amphiphilic multiblock copolymer on its self-assembly structures in dilute solution with Brownian dynamics simulations. Various interesting structures, such as single-flower micelle, multi-flower micelle, and single or multi-bridge structures, are observed. In general, highly hydrophobic components benefit the formation of flower micelle structures, while semi-flexible chains are prone to forming bridge structures. We also study the influence of the ratio between hydrophobic and hydrophilic components on self-assembly structures. From our phase diagram, we find that a high component ratio for the hydrophobic blocks favors the formation of micelles with various structural patterns. A single to multi-flower transition is observed by increasing the chain length of the multiblock copolymer. Well-defined multicompartment wormlike micelles can be obtained from pre-assembled flower micelles in a solvent that is poor for both components. This journal is © The Royal Society of Chemistry 2013.

Wang H.,CAS Changchun Institute of Applied Chemistry | Yoshio M.,Saga University
Chemical Communications | Year: 2010

Ethylene carbonate molecules in electrolyte solutions can bind tightly with PF6 - anions, and prevent the intercalation of these anions into the interlayer spaces of graphite positive electrodes in activated carbon/graphite capacitors. © The Royal Society of Chemistry 2010.

Wang H.,CAS Changchun Institute of Applied Chemistry | Yoshio M.,Saga University
Journal of Power Sources | Year: 2012

The electrochemical capacitor of graphite/activated carbon (AC) using quaternary alkyl ammonium-based organic electrolytes has been proposed. The charge storage mechanisms involve the adsorption of anions into pores of the AC positive electrode and the intercalation of ammonium cations into crystal lattice of the graphite negative electrode, respectively. The intercalation processes of ammonium cations have been investigated by in situ XRD measurements on graphite negative electrodes and the effect of cation size has been intensively addressed. Among the four quaternary alkyl ammonium cations, the intercalation of the biggest cation tetrabutyl ammonium demonstrates the largest degree of crystal lattice expansion of graphite, but the best cycle-ability. By contrast, the insertion of second big cation tetraethyl ammonium into graphite gives the smallest expansion degree of graphite crystal lattice, but poor cycle performance of capacitor. A mechanism has been proposed to explain the above phenomenon. © 2011 Elsevier B.V. All rights reserved.

Nakamura I.,CAS Changchun Institute of Applied Chemistry | Wang Z.-G.,California Institute of Technology
ACS Macro Letters | Year: 2014

We provide a perspective on the thermodynamics of salt-doped block copolymer electrolytes consisting of ion-conducting and inert blocks, taking poly(ethylene oxide)-b-polystyrene and lithium salts as an example. We focus on the origin for enhanced immiscibility between the constituent blocks upon addition of lithium salts and discuss issues from selected experiments and from our recent self-consistent field study. © 2014 American Chemical Society.

Li Y.,Northeast Normal University | Fang L.,Northeast Normal University | Jin R.,Northeast Normal University | Yang Y.,Northeast Normal University | And 3 more authors.
Nanoscale | Year: 2015

As a potential visible-light photocatalyst, the photocatalytic performance of the bulk g-C3N4 synthesized by heating melamine (denote as g-C3N4-M) is limited due to its low specific surface area and the high recombination rate of the photo-induced electron-hole pair. In this paper, a novel g-C3N4-M nanosheet (g-C3N4-MN) obtained from the bulk g-C3N4-M through a thermal exploitation method is employed as an excellent substrate and different amounts of Ag2CO3 nanoparticles are loaded at room temperature. The phase and chemical structure, electronic and optical properties of the Ag2CO3/g-C3N4-MN heterostructures are well-characterized. The photocatalytic activities of the as-prepared Ag2CO3/g-C3N4-MN are evaluated by the degradation of methyl orange (MO) and rhodamine B (RhB) pollutants under visible light irradiation. More importantly, the Ag2CO3/g-C3N4-MN heterostructure has been proved to be an excellent photocatalytic system with an enhanced specific surface area and charge separation rate compared with those of the Ag2CO3/g-C3N4-M system. This journal is © The Royal Society of Chemistry.

Wu S.,Nanyang Technological University | Zeng Z.,Nanyang Technological University | He Q.,Nanyang Technological University | Wang Z.,Nanyang Technological University | And 6 more authors.
Small | Year: 2012

The electrochemical study of single-layer, 2D MoS2 nanosheets reveals a reduction peak in the cyclic voltammetry in NaCl aqueous solution. The electrochemically reduced MoS2 (rMoS2) shows good conductivity and fast electron transfer rate in the [Fe(CN)6] 3-/4- and [Ru(NH3)6]2+/3+ redox systems. The obtained rMoS2 can be used for glucose detection. In addition, it can selectively detect dopamine in the presence of ascorbic acid and uric acid. This novel material, rMoS2, is believed to be a good electrode material for electrochemical sensing applications. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dong S.,Zhejiang University | Zheng B.,Zhejiang University | Xu D.,CAS Changchun Institute of Applied Chemistry | Yan X.,Zhejiang University | And 2 more authors.
Advanced Materials | Year: 2012

A crown ether appended super gelator is designed and synthesized. It can gel a variety of organic solvents and shows excellent gelation properties with both low critical gelation concentration and short gelation time. Due to the introduction of the crown ether moiety and a secondary ammonium unit, the supramolecular gels show reversible gel-sol transitions. The supramolecular gels can also be molded into shape-persistent and free-standing objects. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cheng G.,CAS Changchun Institute of Applied Chemistry
Chemistry (Weinheim an der Bergstrasse, Germany) | Year: 2012

Rare-earth phosphate microspheres with unique structures were developed as affinity probes for the selective capture and tagging of phosphopeptides. Prickly REPO(4) (RE = Yb, Gd, Y) monodisperse microspheres, that have hollow structures, low densities, high specific surface areas, and large adsorptive capacities were prepared by an ion-exchange method. The elemental compositions and crystal structures of these affinity probes were confirmed by energy-dispersive spectroscopy (EDS), powder X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) spectroscopy. The morphologies of these compounds were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nitrogen-adsorption isotherms. The potential ability of these microspheres for selectively capturing and labeling target biological molecules was evaluated by using protein-digestion analysis and a real sample as well as by comparison with the widely used TiO(2) affinity microspheres. These results show that these porous rare-earth phosphate microspheres are highly promising probes for the rapid purification and recognition of phosphopeptides. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pi Z.,CAS Changchun Institute of Applied Chemistry
Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica | Year: 2012

To establish a quick method for evaluation of the antioxidant activities based on the correlation analysis of lignans content and antioxidant activities of Schisandra chinensis fruits. The content of five lignans components in 37 batches of S. chinensis fruits from different regions of Jilin province were measured by HPLC. Simultaneously, the antioxidant activities of the above samples were detected, such as lipid peroxidation inhibition activity in liver (LPIL), kidney (LPIK) and brain (LPIB) and the clearance rate of DPPH (CRD). Bivariate correlation analysis and stepwise regression analysis were carried out by the software of SPSS for windows 11.5. The results of bivariate correlation analysis showed that deoxyschizandrin was negative correlation (P<0.01) to the activity of LPIL, LPIB, CRD. Schisandrin was positive correlation (P<0.01) to the activity of LPIL, LPIB, CRD. Schisandrol B was also positive correlation (P<0.05 or P<0.01) to the above four kinds of antioxidant activity. The results of stepwise regression analysis were mostly consistent with the bivariate correlation analysis results. For the other 10 batches of samples, the simulated antioxidant activities according to the regression equation calculated was consistent with the measured activities. By using the bivariate correlation analysis and linear stepwise regression analysis, the bioactive components related to the antioxidant activity of S. chinensis fruits were found. Meanwhile, the antioxidant activity of samples will be inferred according to the content of Schisandra lignans.

We studied the spinodal decomposition of a homopolymer and ionic liquid mixture. Our theory accounts for the dielectric contrast and hydrogen bond between the polymer and the ionic liquid and the effect of fluctuations in the local density and electrostatic potential. We attempted to rationalize the observed shift in the critical point and the asymmetry of the observed spinodal curve by applying the self-consistent field theory and Langmuir adsorption model. The dielectric contrast between the polymer and the ionic liquid produces a shift in the critical point toward polymer-rich regions. The fluctuation effect yields drastic changes in the trend of the phase boundary. We show that both effects are marked by the appearance of inflection points in the spinodal curve. Although hydrogen bonding also yields similar effects, the spinodal curve rather exhibits a double-well structure or relatively flat structure when combined with the solvation energy of ions. Hydrogen bonding, ion solvation, and the fluctuation have equal significance on the magnitude and trend of the spinodal curve. Our theory provides strategies to dissolve low-dielectric polymers in ionic liquids by altering the dielectric constant of ionic liquids and employing hydrogen bonding. © 2016 American Chemical Society.

Sun X.,Oak Ridge National Laboratory | Sun X.,CAS Changchun Institute of Applied Chemistry | Luo H.,Oak Ridge National Laboratory | Dai S.,Oak Ridge National Laboratory | Dai S.,University of Tennessee at Knoxville
Talanta | Year: 2012

Three functionalized ionic liquids (ILs), tetrabutylammonium di(2-ethylhexyl)phosphate ([TBA][DEHP]), trioctylmethylammonium di(2-ethylhexyl)phosphate ([TOMA][DEHP]), and trihexyl(tetradecyl)phosphonium di(2-ethylhexyl)phosphate ([THTP][DEHP]), are synthesized and characterized. These ILs are used as DEHP-based ionic extractants and are investigated for rare earth elements (REEs) separation in 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([C 6mim][NTf 2]) and diisopropylbenzene (DIPB) along with di(2-ethylhexyl)phosphoric acid (HDEHP). Solubilities of the DEHP-based ionic extractants in [C 6mim][NTf 2] are much better than that of HDEHP in [C 6mim][NTf 2]. We herein report the achievement of enhanced extractabilities and selectivities for separation of REEs using DEHP-based ionic extractants in [C 6mim][NTf 2]. This work highlights the potential of developing a comprehensive ionic liquid-based extraction strategy for REEs using ionic liquids as both extractant and diluent. © 2011 Elsevier B.V. All rights reserved.

Zhang J.,Jilin University | Lu Z.-Y.,Jilin University | Sun Z.-Y.,CAS Changchun Institute of Applied Chemistry
Soft Matter | Year: 2012

The influence of deformability of two-patch particles on their self-assembly behavior is studied via computer simulations. The softness and the deformability of the patchy particles can be controlled by varying the cross-linking densities in different parts of the particles. The patchy particles in a solvent that is bad for patches but good for the matrix form linear thread-like structures when cross-linking densities are low, whereas they form three-dimensional network structures at relatively high cross-linking densities. For patchy particles in a solvent that is good for patches but bad for the matrix, inter-connected membrane structures are obtained at relatively low cross-linking densities, and some cluster structures emerge when cross-linking densities are high. Bicontinuous membranes with better morphologies can be observed by tuning the cross-linking densities of different parts of the patchy particles. © The Royal Society of Chemistry.

Men Y.,CAS Changchun Institute of Applied Chemistry
Soft Matter | Year: 2012

Mechanically soft colloidal crystals of macroscopic dimensions can be obtained via drying charge stabilized polymeric latex dispersions. This article discusses deformation mechanisms of such soft colloidal crystals by means of synchrotron small angle X-ray scattering techniques. Different from conventional crystalline materials, the structural units in the soft colloidal crystals are mechanically deformable. The micro-structural evolution of such soft colloidal crystals as a function of macroscopic deformation was considered. The main features during the deformation process can be identified such as affine deformation of latex particles with respect to the macroscopic one and slips of crystallographic planes within colloidal crystals. Despite the already illustrative experimental data present, understanding of the underlying mechanisms remains still largely descriptive. Therefore, a promising advancement in the knowledge of the fundamental properties of this kind of soft colloidal crystal is desired. © 2012 The Royal Society of Chemistry.

Qian G.,Carleton University | Wang Z.Y.,Carleton University | Wang Z.Y.,CAS Changchun Institute of Applied Chemistry
Advanced Materials | Year: 2012

A series of 2,5-diazapentalene containing dyes with tunable energy gaps are visible and near-infrared halochromic towards various acids and their protonated counterparts represent a new class of thermochromic materials with the near-infrared absorption being switched on at room temperature and off above 50 °C. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Zhang S.,Jilin Agricultural University | Si Y.,Jilin Agricultural University | Wu Z.,CAS Changchun Institute of Applied Chemistry
RSC Advances | Year: 2014

The electronic structure, absorption and emission spectra, as well as phosphorescence efficiency of (ppy)2Ir(PPh2SiO) (1), (ppy)2Ir(P(CH3)2^SiO) (2), (ppy) 2Ir(PH2SiO) (3), and (dfppy)2Ir(PPh 2^SiO) (4) [where ppy = 2-phenylpyridne, dfppy = 2-(2,4- difluorophenyl)pyridine and (PR2^SiO) is an organosilanolate ancillary chelate] were investigated by using density functional theory (DFT) and time-dependent DFT (TDDF) methods. The results revealed that the subtle differences in geometries and electronic structures result in different spectral properties and the quantum yields. Compared with 1, the substituent H in 3 leads to an obvious red shift in absorption spectra, while the substituent CH3 leads to a blue shift for 2 in the emission spectra. Moreover, the S1-T1 splitting energy (ΔES1-T1), the transition dipole moment (μS1, transition from S0 → S1) and the energy gap between the metal-to-ligand charge transfer 3MLCT/π-π* and metal-centered 3MC/d-d states (ΔEMC-MLCT) were also calculated. It was found that the designed complexes 2 and 3 have smaller ΔES1-T1, larger μS1 and ΔEMC-MLCT, which make them have higher quantum yield compared with the experimentally synthesized complexes. Therefore, they are expected to be the potential candidates as emitting materials with high quantum yield. This journal is © the Partner Organisations 2014.

Lin Y.,CAS Changchun Institute of Applied Chemistry | Wang Q.,University of South Carolina
ChemBioChem | Year: 2014

A peptide substrate for transglutaminase factor XIII (FXIIIa) can be caged with a photo-deprotectable group and immobilized to the hydrogel framework. The substrate can be decaged by using multiphoton light to anchor cell-signaling motifs in a spatial specific manner.

Wang H.,CAS Changchun Institute of Applied Chemistry | Yoshio M.,Saga University
Journal of Power Sources | Year: 2010

KPF6 dissolved in propylene carbonate (PC) has been proposed as an electrolyte for activated carbon (AC)/graphite capacitors. The electrochemical performance of AC/graphite capacitor has been tested in XPF6-PC or XBF4-PC electrolytes (X stands for alkali or quaternary alkyl ammonium cations). The AC/graphite capacitor using KPF6-PC electrolyte shows an excellent cycle-ability compared with other electrolytes containing alkali ions. The big decomposition of the PC solvent at the AC negative electrode is considerably suppressed in the case of KPF6-PC, which fact has been correlated with the mild solvation of K+ by PC solvent. The relationship between the ionic radius of cation and the corresponding specific capacitance of AC negative electrode also proves that PC-solvated K+ ions are adsorbed on AC electrode instead of naked K+ ions. © 2009 Elsevier B.V. All rights reserved.

Lu M.F.,CAS Changchun Institute of Applied Chemistry | Waerenborgh J.C.,University of Lisbon | Greaves C.,University of Birmingham
Angewandte Chemie - International Edition | Year: 2013

Mix and match: Topotactic hydride reduction allows the first synthesis of the fully reduced parent phase, Sr4Fe6O12, of the important family Sr4Fe6O13±δ. The structure provides a rare example of pairs of edge-linked tetrahedra, in this case containing a random arrangement of FeII and Fe III centers at 300 K. On cooling, charge order occurs so that each pair of tetrahedra has one FeII (white) and one FeIII (black) center. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Qian Q.,Renmin University of China | Huang X.,Renmin University of China | Zhang X.,Renmin University of China | Xie Z.,CAS Changchun Institute of Applied Chemistry | Wang Y.,Renmin University of China
Angewandte Chemie - International Edition | Year: 2013

Taking advantage of photothermal conversion, the surface pores of water-dispersible single-walled carbon nanotubes assembled on polymer particles were rapidly closed by NIR irradiation to produce macroporous polymeric microspheres with multiple interconnected chambers. These particles can act as smart containers to encapsulate and hold DNA molecules. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Yan J.,CAS South China Botanical Garden | Li J.,CAS Changchun Institute of Applied Chemistry | Ye Q.,CAS South China Botanical Garden | Li K.,CAS South China Botanical Garden
Chemical Geology | Year: 2012

Chemical concentrations and export rates from surface water were analyzed in Houzhai Karst Basin (HKB, area 80.65km 2 in total), southwest China, for the past two decades from 1986 to 2007. Surface water chemistry was dominated by ions of calcium (Ca 2+), magnesium (Mg 2+), bicarbonate (HCO 3 -) and sulfate (SO 4 2-), which together made up 96% (by weight) of the total dissolved solids measured in this study. Seasonal variability of chemical export rates was positively correlated with surface runoff discharge, with the concentrations generally diluting at high discharge. From 1986 to 2007, as a result of the responses of karst weathering to climatic factors, the concentrations of Ca 2+, Mg 2+, HCO 3 -, and SO 4 2- slowly increased in surface water. By contrast, changes in the concentrations of sodium (Na +), potassium (K +), and chloride (Cl -) showed a slowly decreasing pattern. We also found that the annual dissolved inorganic carbon (DIC) flux ranged from 10.1 to 34.1gCm -2yr -1, with an average value of 24.2gCm -2yr -1. Rainfall had the most important influence on DIC flux, although water pH may greatly affect the proportions of the three fractions (CO 2, HCO 3 -, CO 3 2-) of DIC. High water temperature in the wet season may reduce the solubility of CO 2 in water and consequently affect DIC export rate, but this effect is much smaller than that of rainfall. Based on the chemical mass balance in surface water, our results indicate that high concentrations of SO 4 2- by the large gypsum (CaSO 4.2H 2O) dissolution offset some anions such as HCO 3 - in karst water, which can partly explain why carbon uptake is often overestimated by the empirical model using concentrations of HCO 3 - in this karst water. It is concluded that the fluvial flux of DIC from karst water is important to the regional or national carbon budgets. © 2012.

Tong S.,Jilin University | Liu Q.,Jilin University | Li Y.,Jilin University | Zhou W.,Jilin University | And 2 more authors.
Journal of Chromatography A | Year: 2012

Novel monolithic capillary columns with embedded graphene were developed and used for polymer monolith microextraction (PMME) coupled to LC-MS analysis. The column was prepared inside fused silica capillaries (320μm, i.d.) using thermally initiated free-radical polymerization with butyl methacrylate (BMA) as monomer, ethylene dimethacrylate (EDMA) as cross-linker, and 1,4-butanediol and 1-propanol as porogens. Graphene (GN) was incorporated into the poly(BMA-EDMA) monolith to enhance the loading capacity. The obtained GN and the poly(BMA-EDMA-GN) monolith were characterized by transmission electron microscope (TEM), atomic force microscopic (AFM) and scanning electron microscopy (SEM). The extraction performance of the monolithic column was evaluated by glucocorticoids (GCs) as the analytes. The operation parameters of PMME including desorption solvent, sample flow rate, sample volume, sample pH, and eluent flow rate were studied and optimized. When compared to the parent poly(BMA-EDMA) column and direct sample analysis, high enrichment capacity was observed in the case of GN-entrapped monolith. The GN incorporated monolithic capillary showed satisfactory reusability and stability during extraction. The limits of detection (S/N. =3) for nine GCs were in the range of 0.13-1.93. ng/mL. Relative standard deviations for the determination of the target GCs were less than 14.5%. Finally, the PMME method, based on the developed monolithic capillary as the extraction media, was successfully applied to the determination of nine GCs in cosmetics. The recoveries of GCs spiked in different matrices ranged from 83.7% to 103.8%. © 2012 Elsevier B.V.

Wang N.,CAS Changchun Institute of Applied Chemistry | Chen Z.,Jilin University | Wei W.,Jilin University | Jiang Z.,Jilin University
Journal of the American Chemical Society | Year: 2013

Thanks to their many favorable advantages, polymer solar cells exhibit great potential for next-generation clean energy sources. Herein, we have successfully designed and synthesized a series of new fluorinated benzothiadiazole-based conjugated copolymers PBDTTEH-DT HBTff (P1), PBDTTEH-DTEHBTff (P2), and PBDTHDO-DTHBTff (P3). The power conversion efficiencies of 4.46, 6.20, and 8.30% were achieved for P1-, P2-, and P3-based devices within ∼100 nm thickness active layers under AM 1.5G illumination without any processing additives or post-treatments, respectively. The PCE of 8.30% for P3 is the highest value for the reported traditional single-junction polymer solar cells via a simple fabrication architecture without any additives or post-treatments. In addition, it is noteworthy that P3 also allows making high efficient polymer solar cells with high PCEs of 7.27 and 6.56% under the same condition for ∼200 and ∼300 nm thickness active layers, respectively. Excellent photoelectric properties and good solubility make polymer P3 become an alternative material for high-performance polymer solar cells. © 2013 American Chemical Society.

Wang L.,Japan National Institute of Materials Science | Wang L.,CAS Changchun Institute of Applied Chemistry | Yamauchi Y.,Japan National Institute of Materials Science | Yamauchi Y.,Waseda University
Journal of the American Chemical Society | Year: 2013

We report a facile synthesis of Pt-Pd bimetallic nanoparticles, named "metallic nanocages", with a hollow interior and porous dendritic shell. This synthesis is easily achieved by selective chemical etching of Pd cores from dendritic Pt-on-Pd nanoparticles. The obtained Pt-Pd nanocages show superior catalytic activity for methanol oxidation reaction compared to other Pt-based materials reported previously. © 2013 American Chemical Society.

Chen W.,CAS Changchun Institute of Applied Chemistry | Chen S.,University of California at Santa Cruz
Journal of Materials Chemistry | Year: 2011

IrxPt100-x alloy nanoparticles with varied compositions (x = 100, 75, 67, 50, 34, and 0) were synthesized by a thermolytic process at varied ratios of the IrCl3 and PtCl2 precursors. High-resolution transmission electron microscopic (HRTEM) measurements showed that the nanoparticles all exhibited well-defined crystalline structures with the average core diameters around 2 nm; and the elemental compositions were determined by X-ray photoelectron spectroscopic (XPS) measurements. The electrocatalytic activities of the IrxPt 100-x nanoparticles toward formic acid oxidation were then examined by electrochemical measurements, including cyclic voltammetry (CV), chronoamperometry, and electrochemical impedance spectroscopy (EIS). In the CV studies, it was found that both the current density of formic acid oxidation and the tolerance to CO poisoning were strongly dependent on the composition of the iridium-platinum alloy nanoparticles, with the best performance found with the Ir50Pt50 nanoparticles. Due to heavy CO poisoning, Pt nanoparticles exhibited the lowest catalytic performance among the series of nanoparticles (excluding Ir nanoparticles). The Ir50Pt50 nanoparticles also showed the maximum current density and stability in chronoamperometric measurements. Consistent results were obtained in electrochemical impedance spectroscopic studies of the electron transfer kinetics involved. Notably, of all the nanoparticle electrocatalysts, an inductive component, i.e. negative impedance, was observed in the potential windows where CO was removed by electro-oxidation; and the charge transfer resistance was found to be the lowest with the Ir50Pt50 nanoparticles. Based on the current density and peak potential of formic acid oxidation, the ratio of the anodic peak current density to the cathodic peak current density measured in CV studies, the stability manifested in chronoamperometric measurements and the tolerance to CO poisoning displayed in EIS measurements, the electrocatalytic performance of the IrPt alloy nanoparticles was found to decrease in the order of Ir50Pt 50 > Ir67Pt33 > Ir75Pt 25 > Ir34Pt66 > Pt. That is, among the series of IrPt alloy nanoparticles, the sample with the Ir/Pt atomic ratio of 1:1 showed the highest electrocatalytic activity towards formic acid oxidation, which might be ascribed to the bifunctional reaction mechanism of bimetallic alloy electrocatalysts. © 2011 The Royal Society of Chemistry.

Li H.M.,Jilin University | Sun D.Q.,Jilin University | Cai X.L.,CAS Changchun Institute of Applied Chemistry | Dong P.,Jilin University | Wang W.Q.,Jilin University
Materials and Design | Year: 2012

Laser welding of TiNi shape memory alloy wire to stainless steel wire using Ni interlayer was investigated. The results indicated that the Ni interlayer thickness had great effects on the chemical composition, microstructure, gas-pore susceptibility and mechanical properties of laser-welded joints. With an increase of Ni interlayer thickness, the weld Ni content increased and the joint properties increased due to decreasing brittle intermetallic compounds (TiFe2 and TiCr2). The joint fracture occurred in the fusion zone with a brittle intermetallic compound layer. The tensile strength and elongation of the joints reached the maximum values (372MPa and 4.4%) when weld Ni content was 47.25wt.%. Further increasing weld Ni content resulted in decreasing the joint properties because of forming more TiNi3 phase, gas-pores and shrinkage cavities in the weld metals. It is necessary to select suitable Ni interlayer thickness (weld composition) for improving the mechanical properties of laser-welded joints. © 2012 Elsevier Ltd.

Fan H.,Jilin University | Li H.,CAS Changchun Institute of Applied Chemistry | Liu B.,Jilin University | Lu Y.,Jilin University | And 2 more authors.
ACS Applied Materials and Interfaces | Year: 2012

A series of Bi 2O 3/BaTiO 3 composite photocatalysts with different mass ratios of Bi 2O 3 vs BaTiO 3 were prepared by an impregnating-annealing method. X-ray diffraction (XRD), high-resolution transmission electron microscopic (HRTEM), and UV-vis diffuse reflection spectroscopy (DRS) confirmed that Bi 2O 3 and BaTiO 3 coexisted in the composites. The results of surface photovoltage (SPV) experiments showed enhancements of photovoltaic response in composites, which indicated a higher separation efficiency of photoinduced charges due to the establishment of an efficient interfacial electric field between Bi 2O 3 and BaTiO 3 in the composites. The consistency of phtocatalytic activity and photovoltaic response intensity of photocatalysts showed that the efficiency interfacial electric field between Bi 2O 3 and BaTiO 3 played an important role in improving the degradation efficiency of Rhodamine B (RhB). The 60%-Bi 2O 3/BaTiO 3 sample with the best activity was found by optimizing the mass ratios of Bi 2O 3 vs. BaTiO 3. On the basis of the work function (WF) measurements, a reasonable energy band diagram was proposed for BaTiO 3/Bi 2O 3 composite. It would be helpful in designing and constructing high efficiency heterogeneous semiconductor photocatalyst. © 2012 American Chemical Society.

Zhang Y.,Dalian University of Technology | Xue D.,Dalian University of Technology | Xue D.,CAS Changchun Institute of Applied Chemistry
Functional Materials Letters | Year: 2012

α-MnO2 electrode materials with sphere-, rod- and flower-like nanostructures were for the first time fabricated by a redox reaction between KMnO4 and NaHSO3 in chemical bath. Crystal structure and morphology of the as-crystallized samples were characterized by X-ray diffraction and scanning electron microscopy. The influence of reaction temperature and H+ concentration on both morphology and crystalline nature was investigated. Their electrochemical behaviors were investigated by cycling voltammetry and galvanostatic charge/discharge measurements in a three-electrode glass cell. Depending upon different synthesis conditions of α-MnO2 electrodes, their specific capacitance values varied in the range of 43 to 197 F g-1 at the current density of 1 A g-1. Moreover, their specific capacitance values decrease with increasing crystallinity and particle size. In this work, we conclude that the energy storage mechanism is closely related to the particle aggregation state of electrode materials. © 2012 World Scientific Publishing Company.

Li K.,Dalian University of Technology | Yang P.,Dalian University of Technology | Xue D.,Dalian University of Technology | Xue D.,CAS Changchun Institute of Applied Chemistry
Acta Materialia | Year: 2012

We have presented an efficient method to predict the anisotropic hardness of crystalline materials along different crystallographic directions or on different crystallographic planes in terms of electronegativity. Bond stretching and bending strengths, respectively, are proposed to characterize the ability of a chemical bond to resist stretching and bending deformation, which are the main microscopic deformations in single crystals when measuring indentation hardness. Good agreement between the calculated and experimental values of anisotropic hardness for a large range of crystalline materials has been achieved, including sphalerite, wurtzite and rocksalt structured materials, as well as oxides (e.g. α-SiO2 and LaGaO3) and graphite. The anisotropic hardness values of other important materials, such as B12 analogs, group IVA nitrides, tungsten carbide structured materials, and transition metal di- and tetra-borides, were quantitatively predicted. We found that materials with the same crystal structure have the same or similar hardness anisotropy. Furthermore, the more orderly bond arrangement in single crystals and the greater bond ionicity often result in greater hardness anisotropy. This work shines a light on the nature of hardness and on studies of the anisotropy of other macroscopic properties of crystalline materials. © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Zhang J.,Zhengzhou University | Wang K.,Zhengzhou University | Xu Q.,Zhengzhou University | Zhou Y.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
ACS Nano | Year: 2015

To well address the problems of large volume change and dissolution of Fe3O4 nanomaterials during Li+ intercalation/extraction, herein we demonstrate a one-step in situ nanospace-confined pyrolysis strategy for robust yolk-shell nanospindles with very sufficient internal void space (VSIVS) for high-rate and long-term lithium ion batteries (LIBs), in which an Fe3O4@Fe3C core@shell nanoparticle is well confined in the compartment of a hollow carbon nanospindle. This particular structure can not only introduce VSIVS to accommodate volume change of Fe3O4 but also afford a dual shell of Fe3C and carbon to restrict Fe3O4 dissolution, thus providing dual roles for greatly improving the capacity retention. As a consequence, Fe3O4@Fe3C-C yolk-shell nanospindles deliver a high reversible capacity of 1128.3 mAh g-1 at even 500 mA g-1, excellent high rate capacity (604.8 mAh g-1 at 2000 mA g-1), and prolonged cycling life (maintaining 1120.2 mAh g-1 at 500 mA g-1 for 100 cycles) for LIBs, which are much better than those of Fe3O4@C core@shell nanospindles and Fe3O4 nanoparticles. The present Fe3O4@Fe3C-C yolk-shell nanospindles are the most efficient Fe3O4-based anode materials ever reported for LIBs. © 2015 American Chemical Society.

Yan X.,Zhejiang University | Xu D.,CAS Changchun Institute of Applied Chemistry | Chi X.,Zhejiang University | Chen J.,Zhejiang University | And 4 more authors.
Advanced Materials | Year: 2012

A cross-linked supramolecular polymer network gel is designed and prepared, which shows reversible gel-sol transitions induced by changes in pH, temperature, cation concentration, and metal co-ordination. The gel pore size is controlled by the amount of cross-linker added to the system, and the material can be molded into shape-persistent, free-standing objects with elastic behavior. These features are all due to the dynamically reversible host-guest complexation and good mechanical properties of the cross-linked polymer network. No single organogel has previously been reported to possess all of these features, making this supramolecular gel an unprecedentedly intelligent soft material. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wang H.-G.,Changchun University of Science and Technology | Wang Y.,CAS Changchun Institute of Applied Chemistry | Li Y.,Changchun University of Science and Technology | Wan Y.,Changchun University of Science and Technology | Duan Q.,Changchun University of Science and Technology
Carbon | Year: 2015

Crumpled nitrogen-doped porous carbon sheets are successfully fabricated via chemical activation of polypyrrole-functionalized graphene sheets with KOH (APGs). The obtained APGs with nitrogen doping, high surface area, porous and crumpled structure exhibit exceptional electrochemical performances as the electrode material for LIBs, including a superhigh reversible specific capacity of 1516.2 mAh g-1, excellent cycling stability over 10,000 cycles, and good rate capability (133.2 mAh g-1 even at a very high current density of 40 A g-1). The chemical activation synthesis strategy might open new avenues for the design of high-performance carbon-based anode materials.

Chen Y.,University of St. Andrews | Freunberger S.A.,University of St. Andrews | Freunberger S.A.,University of Graz | Peng Z.,University of St. Andrews | And 4 more authors.
Nature Chemistry | Year: 2013

The non-aqueous Li-air (O2) battery is receiving intense interest because its theoretical specific energy exceeds that of Li-ion batteries. Recharging the Li-O2 battery depends on oxidizing solid lithium peroxide (Li2O2), which is formed on discharge within the porous cathode. However, transporting charge between Li 2O2 particles and the solid electrode surface is at best very difficult and leads to voltage polarization on charging, even at modest rates. This is a significant problem facing the non-aqueous Li-O2 battery. Here we show that incorporation of a redox mediator, tetrathiafulvalene (TTF), enables recharging at rates that are impossible for the cell in the absence of the mediator. On charging, TTF is oxidized to TTF+ at the cathode surface; TTF+ in turn oxidizes the solid Li2O 2, which results in the regeneration of TTF. The mediator acts as an electron-hole transfer agent that permits efficient oxidation of solid Li 2O2. The cell with the mediator demonstrated 100 charge/discharge cycles. © 2013 Macmillan Publishers Limited.

Huang S.,CAS Changchun Institute of Applied Chemistry | Jiang S.,Tianjin University
RSC Advances | Year: 2014

Biocompatible and biodegradable block copolymers (BBCPs) have become increasingly important in polymer science, and have many potential applications in polymer materials. The structures of BBCPs, which are determined by the competition between crystallization, microphase separation, kinetics and processing, have a tremendous influence on the final properties and applications. In this review, the most recent advances are highlighted in the crystalline structures and morphologies of BBCPs with at least one crystalline block. Particular emphasis is placed on the influences of chemical composition, molecular architecture, crystallization pathway, and film thickness on the structures and morphologies of the block copolymers. The formation and the characteristics of the structures grown in the block copolymers are helpful for understanding the interplay between crystallization and phase segregation, morphologies, structural evolution and their applications. © 2014 the Partner Organisations.

Nomura K.,Tokyo Metroplitan University | Liu J.,CAS Changchun Institute of Applied Chemistry
Dalton Transactions | Year: 2011

Selected examples concerning effects of both cyclopentadienyl fragment (Cp′) and anionic donor ligand (Y) in nonbridged modified half-titanocenes of the type, Cp′TiX2(Y) (X = halogen, alkyl), as new type of olefin polymerisation catalysts have been reviewed. These complexes displayed unique characteristics not only for ethylene (co)polymerisation but also for syndiospecific styrene polymerisation, ethylene/styrene copolymerisation; precise fine tuning of the ligand substituents plays an important role for the successful (co)polymerisation; a different mechanistic consideration for the syndiospecific styrene polymerisation, which can explain the copolymerisation behaviour in this catalysis, has also been introduced. © 2011 The Royal Society of Chemistry.

Sun L.,Changchun University of Technology | Zhao Z.,Changchun University of Science and Technology | Zhou Y.,CAS Changchun Institute of Applied Chemistry | Liu L.,Changchun University of Technology
Nanoscale | Year: 2012

Owing to their extensive practical applications and fundamental importance, the controllable synthesis of well-faceted anatase TiO 2 crystal with high percentage of reactive facets has attracted increasing attention. Here, nano-sized anatase TiO 2 sheets mainly dominated by {001} facets had been prepared on graphene sheets by using a facile solvothermal synthetic route. The percentage of {001} facets in TiO 2 nanosheets was calculated to be ca. 64%. The morphologies, structural properties, growth procedures and photocatalytic activities of the resultant TiO 2/graphene nanocomposites were investigated. In comparison with commercial P25 and pure TiO 2 nanosheets, the composite exhibited significant improvement in photocatalytic degradation of the azo dye Rhodamine B under visible light irradiation. The enhancement of photocatalytic activity and stability was attributed to the effective charge anti-recombination of graphene and the high catalytic activity of {001} facets. © 2012 The Royal Society of Chemistry.

Jin Y.,CAS Changchun Institute of Applied Chemistry
Advanced Materials | Year: 2012

The fields of biosensing and nanomedicine have recently witnessed an explosion of interest and progress in the design and study of plasmonic Au nanostructures (p-AuNSs) or metamaterials geared towards a broad range of biological and biomedical applications. Due to their tunable and versatile plasmonic properties, such artificially engineered p-AuNSs and materials have the potential to push biosensor sensitivity towards the single-molecule detection limit, enabling new bioimaging modalities and new analytical techniques and tools capable of single-molecule detection, analysis and manipulation, and to revolutionize the diagnosis and treatment of many diseases, including cancers. This report summarizes and highlights recent major advances in the emerging field of bioapplication-oriented engineering of p-AuNSs and hybrids, focusing on design considerations and ways to carry them out. A brief overview of the optical properties of p-AuNSs is introduced, and then the importance of plasmonic engineering and future promising research directions and challenges in the field are discussed. Nanoengineering of plasmonic nanostructures and metamaterials geared towards biosensing and nanomedicine has recently witnessed an explosion of interest and progress due to their tunable and versatile plasmonic properties. This report summarizes and highlights recent major advances in the emerging field of bioapplication-oriented nanoengineering of plasmonic Au nanostructures, hybrids, and metamaterials. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

We demonstrated a simple, in situ reduction route to the synthesis of two-dimensional graphene oxide/SiO(2) (GSCN) hybrid nanostructures consisting of Au nanoparticles (Au NPs) supported on the both sides of GSCN. The as-prepared GSCN/Au NPs hybrid nanomaterials exhibited good catalytic activity for the reduction of 4-nitrophenol. This approach provided a useful platform based on GO hybrid nanomaterials for the fabrication of GSCN/Au NPs hybrid nanomaterials, which could be very useful in catalytic applications.

Zhao Z.,Changchun University of Science and Technology | Zhang G.,CAS Changchun Institute of Applied Chemistry | Gao Y.,Changchun University of Science and Technology | Yang X.,Changchun University of Science and Technology | Li Y.,Changchun University of Science and Technology
Chemical Communications | Year: 2011

Ultrasensitive visual detection of hydrazine hydrate using a Au nanoparticles-based colorimetric sensing system (ANCSS) is reported for the first time, which is based on the hydrogen bonding recognition and the modality change of hydrogen bonding from "linear" (simple hydrogen bond interactions) to "nonlinear" (a complicated hydrogen bond network) between as-modified Au nanoparticles (Au NPs). © 2011 The Royal Society of Chemistry.

Yan X.,Zhejiang University | Xu D.,CAS Changchun Institute of Applied Chemistry | Chen J.,Zhejiang University | Zhang M.,Zhejiang University | And 3 more authors.
Polymer Chemistry | Year: 2013

A cross-linked supramolecular polymer network gel was prepared by orthogonal self-assembly of two homoditopic monomers and a metallic cross-linker. The gel is transparent and free-standing, which not only shows an interesting gel-sol transition in response to quadruple-stimuli, but also exhibits self-healing properties, as can be seen by the naked eye and as evidenced by rheological characterization. These unique features are all due to the dynamically reversible host-guest complexation and good mechanical properties of the cross-linked polymer network. Therefore, these fascinating properties make this supramolecular gel an unprecedentedly intelligent material. © 2013 The Royal Society of Chemistry.

Liu J.,CAS Changchun Institute of Applied Chemistry | Durstock M.,Air Force Research Lab | Dai L.,Case Western Reserve University
Energy and Environmental Science | Year: 2014

Owing to their solution processability, unique two-dimensional structure, and functionalization-induced tunable electronic structures, graphene oxide (GO) and its derivatives have been used as a new class of efficient hole- and electron-extraction materials in polymer solar cells (PSCs). Highly efficient and stable PSCs have been fabricated with GO and its derivatives as hole- and/or electron-extraction layers. In this review, we summarize recent progress in this emerging research field. We also present some rational concepts for the design and development of the GO-based hole- or electron-extraction layers for high-performance PSCs, along with challenges and perspectives. This journal is © the Partner Organisations 2014.

Cheng Y.,CAS Changchun Institute of Applied Chemistry
Biomacromolecules | Year: 2012

Thermosensitive hydrogels based on PEG and poly(l-glutamate)s bearing different hydrophobic side groups were separately synthesized by the ring-opening polymerization (ROP) of l-glutamate N-carboxyanhydrides containing different alkyl protected groups, that is, methyl, ethyl, n-propyl, and n-butyl, using mPEG(45)-NH(2) as macroinitiator. The resulting copolymers underwent sol-gel transitions in response to temperature change. Interestingly, the polypeptides containing methyl and ethyl showed significantly lower critical gelation temperatures (CGTs) than those bearing n-propyl and butyl side groups. Based on the analysis of (13)C NMR spectra, DLS, circular dichroism spectra, and ATR-FTIR spectra, the sol-gel transition mechanism was attributed to the dehydration of poly(ethylene glycol) and the increase of β-sheet conformation content in the polypeptides. The in vivo gelation test indicated that the copolymer solution (6.0 wt %) immediately changed to a gel after subcutaneous injection into rats. The mass loss of the hydrogel in vitro was accelerated in the presence of proteinase K, and the MTT assay revealed that the block copolymers exhibited no detectable cytotoxicity. The present work revealed that subtle variation in the length of a hydrophobic side group displayed the decisive effect on the gelation behavior of the polypeptides. In addition, the thermosensitive hydrogels could be promising materials for biomedical applications due to their good biocompatibility, biodegradability, and the fast in situ gelation behavior.

Sun L.,CAS Changchun Institute of Applied Chemistry
Nanoscale | Year: 2010

Here, we describe the synthesis of peptide- and/or protein-functionalized Fe(2)O(3) core-Au shell (Fe(2)O(3)@Au) nanoparticles for imaging and targeting of living cells. When functionalized with the transmembrane peptide RRRRRRRR (R(8)), the Fe(2)O(3)@Au nanoparticles (R(8)-Fe(2)O(3)@Au) are able to serve as cellular trafficking agents with excellent biocompatibility. The internalization mechanism and delivery efficiency of the R(8)-Fe(2)O(3)@Au nanoparticles have been characterized with dark-field microscopy and fluorescence confocal scanning laser microcopy. Experimental result suggests that the R(8)-Fe(2)O(3)@Au nanoparticles are internalized initially by binding with the membrane-associated proteoglycans on cell surfaces, especially heparan sulfate proteoglycans (HSPGs), following an energy-dependent endocytosis process to enter into living cells. After conjugation with the epidermal growth factor receptor antibody (anti-EGFR), these nanoparticles can also be used for the recognition of cell membrane antigens to specifically label tumor cells.

Zhang N.,TU Munich | Zhang N.,CAS Changchun Institute of Applied Chemistry | Salzinger S.,TU Munich | Rieger B.,TU Munich
Macromolecules | Year: 2012

Novel statistic copolymers of dialkyl vinylphosphonates have been synthesized via rare earth metal-mediated group transfer polymerization using easily accessible tris(cyclopentadienyl)ytterbium. The copolymerization parameters have been determined by activity measurements showing the formation of almost perfectly random copolymers (r1, r2 ∼ 1). Thus, the polymerization rate of vinylphosphonate GTP is mainly limited by the steric demand of growing polymer chain end. The obtained copolymers of diethyl vinylphosphonate and dimethyl or di-n-propyl vinylphosphonate show thermoresponsive properties, i.e., exhibit a tunable lower critical solution temperature following a coil-globule transition mechanism, with cloud points between 5 and 92 C. Hereby, the LCST can be precisely adjusted by varying the comonomer composition and correlates linearly with the content of hydrophilic/hydrophobic comonomer. These thermoresponsive poly(vinylphosphonate) s, exhibiting a sharp and reversible phase transition, and minor environmental effects such as concentration and additives on their cloud point, are promising candidates in biomedical applications. © 2012 American Chemical Society.

Wu D.,Nankai University | Wu D.,Institute of Seawater Desalination And Multipurpose Utilization | Song X.,Nankai University | Tang T.,CAS Changchun Institute of Applied Chemistry | Zhao H.,Nankai University
Journal of Polymer Science, Part A: Polymer Chemistry | Year: 2010

Well-defined macromolecular brushes with poly (N-isopropyl acrylamide) (PNIPAM) side chains on random copolymer backbones were synthesized by "grafting from" approach based on click chemistry and reversible additionfragmentation chain transfer (RAFT) polymerization. To prepare macromolecular brushes, two linear random copolymers of 2-(trimethylsilyloxy) ethyl methacrylate (HEMA-TMS) and methyl methacrylate (MMA) (poly(MMA-co-HEMA- TMS)) were synthesized by atom transfer radical polymerization and were subsequently derivated to azide-containing polymers. Novel alkyne-terminated RAFT chain transfer agent (CTA) was grafted to polymer backbones by copper-catalyzed 1,3-dipolar cycloaddition (azide-alkyne click chemistry), and macro-RAFT CTAs were obtained. PNIPAM side chains were prepared by RAFT polymerization. The macromolecular brushes have well-defined structures, controlled molecular weights, and molecular weight distributions (M w/Mn ≦ 1.23). The RAFT polymerization of NIPAM exhibited pseudo-first-order kinetics and a linear molecular weight dependence on monomer conversion, and no detectable termination was observed in the polymerization. The macromolecular brushes can self-assemble into micelles in aqueous solution. © 2009 Wiley Periodicals, Inc.

Zhang Z.,Jilin University | Duan H.,Jilin University | Li S.,CAS Changchun Institute of Applied Chemistry | Lin Y.,Jilin University
Langmuir | Year: 2010

The synthesis and characterization of carbon-coated ferromagnetic nanoparticles that organize into 1-D assemblies of micrometer-sized ferromagnetic chains is described. A controlled aromatization and carbonization of glucose under hydrothermal reaction conditions enabled the preparation of carbonaceous surfactants that were used as shells for the coating of ferromagnetic Fe3O4 nanospheres with a uniform size distribution. Under controlled experimental conditions, it was, for the first time, demonstrated that glucose could be employed as the carbon source in the preparation of continuous 1-D carbon nanoparticle chains with magnetic nanosphere inclusions. The functional groups on the carbon surface will facilitate the linkage of functional groups or catalytic species to the surface in future application. The salient feature of the reported method was the assembly of magnetic nanospheres under hydrothermal reaction conditions in the absence of external fields. © 2010 American Chemical Society.

Chen R.,Changchun Normal University | Liu Z.,CAS Changchun Institute of Applied Chemistry | Zhao J.,Changchun Normal University | Meng F.,Changchun Normal University | And 2 more authors.
Food Chemistry | Year: 2011

A water-soluble polysaccharide obtained from Acanthopanax senticosus leaves (ASL), was fractionated by DEAE-Sepharose fast-flow column chromatography, and purified by Sephadex G-75 gel-permeation column chromatography. The characteristics of ASP-2-1 were determined by chemical analysis, high-performance capillary electrophoresis (HPCE), high-performance gel-permeation chromatography (HPGPC). The results show that ASP-2-1 contained 89.47% carbohydrate, 7.45% uronic acid, 2.16% protein and seven kinds of monosaccharides including rhamnose, xylose, glucose, mannose, arabinose, galactose and glucuronic acid in a molar ratio of 7.45:18.63:25.15:0.93:8.35:2. 79:5.69, with an average molecular weight of about 14,573 Da. Furthermore, the immunobiological and antioxidant activities, in vitro, of ASP-2-1 were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and ferric-reducing antioxidant power assay (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH.), superoxide radical (.O2 -) and hydroxyl radical (.OH) free radical-scavenging assay, respectively. The results showed that ASP-2-1 exhibited significantly higher immunomodulatory activities against the lymphocyte proliferation in vitro, pronounced reductive power (FRAP value: 785.1 μM at 0.2 mg/ml), strong hydroxyl radical (89.56% at 1 mg/ml) scavenging activity, moderate superoxide radicals (65.32% at 1 mg/ml) and DPPH radicals (68.9% at 1 mg/ml) scavenging activities. ASP-2-1 should be explored as a novel and potential natural antioxidant and immunostimulating agent for use in functional foods or medicine. © 2011 Elsevier Ltd. All rights reserved.

Han F.-S.,CAS Changchun Institute of Applied Chemistry | Han F.-S.,Dalian University of Technology
Chemical Society Reviews | Year: 2013

In the transition-metal-catalyzed cross-coupling reactions, the use of the first row transition metals as catalysts is much more appealing than the precious metals owing to the apparent advantages such as cheapness and earth abundance. Within the last two decades, particularly the last five years, explosive interests have been focused on the nickel-catalyzed Suzuki-Miyaura reactions. This has greatly advanced the chemistry of transition-metal-catalyzed cross-coupling reactions. Most notably, a broad range of aryl electrophiles such as phenols, aryl ethers, esters, carbonates, carbamates, sulfamates, phosphates, phosphoramides, phosphonium salts, and fluorides, as well as various alkyl electrophiles, which are conventionally challenging, by applying palladium catalysts can now be coupled efficiently with boron reagents in the presence of nickel catalysts. In this review, we would like to summarize the progress in this reaction. © 2013 The Royal Society of Chemistry.

Hensel Z.,Johns Hopkins University | Feng H.,State University of New York at Stony Brook | Han B.,State University of New York at Stony Brook | Hatem C.,Johns Hopkins University | And 4 more authors.
Nature Structural and Molecular Biology | Year: 2012

Gene expression is inherently stochastic; precise gene regulation by transcription factors is important for cell-fate determination. Many transcription factors regulate their own expression, suggesting that autoregulation counters intrinsic stochasticity in gene expression. Using a new strategy, cotranslational activation by cleavage (CoTrAC), we probed the stochastic expression dynamics of cI, which encodes the bacteriophage Î repressor CI, a fate-determining transcription factor. CI concentration fluctuations influence both lysogenic stability and induction of bacteriophage Î. We found that the intrinsic stochasticity in cI expression was largely determined by CI expression level irrespective of autoregulation. Furthermore, extrinsic, cell-to-cell variation was primarily responsible for CI concentration fluctuations, and negative autoregulation minimized CI concentration heterogeneity by counteracting extrinsic noise and introducing memory. This quantitative study of transcription factor expression dynamics sheds light on the mechanisms cells use to control noise in gene regulatory networks. © 2012 Nature America, Inc. All rights reserved.

Zhang L.,University of Chinese Academy of Sciences | Zhu J.,University of Chinese Academy of Sciences | Guo S.,University of Chinese Academy of Sciences | Li T.,University of Chinese Academy of Sciences | And 2 more authors.
Journal of the American Chemical Society | Year: 2013

Photoinduced electron transfer (PET) has been observed for the first time between DNA/Ag fluorescent nanoclusters (NCs) and G-quadruplex/hemin complexes, accompanied by a decrease in the fluorescence of the DNA/Ag NCs. In this PET process, a parallel G-quadruplex and the sensing sequences are blocked by a duplex. The specific combination of targets with the sensing sequence triggers the release of the G-quadruplex and allows it to fold properly and bind hemin to form a stable G-quadruplex/hemin complex. The complex proves favorable for PET because it makes the G-quadruplex bind hemin tightly, which promotes the electron transfer from the DNA/Ag NCs to the hemin FeIII center, thus resulting in a decrease in the fluorescence intensity of the DNA/Ag NCs. This novel PET system enables the specific and versatile detection of target biomolecules such as DNA and ATP with high sensitivity based on the choices of different target sequences. © 2013 American Chemical Society.

Ma D.-G.,CAS Changchun Institute of Applied Chemistry
Chinese Journal of Liquid Crystals and Displays | Year: 2016

Organic light-emitting diodes (OLEDs)have become important technologies of display and lighting, which not only achieve applications in industry, but also obtain deep studies in science. It is related to chemistry and material science, also includes the scientific contents of physics, optics, electronics, device physics, condensed physics and semiconductor physics, etc.. This paper will introduce the physics basis and design principle of high efficiency OLEDs in device structures based on work mechanism and related materials, and finally prospects the applications of OLEDs in display and lighting. © 2016 Science Press. All rights reserved.

Contamination of food and drinking water by dangerous levels of nitrite has always been of strong concern and toxicity of this inorganic anion calls for convenient detection methods. Although some visible approaches were developed to deal with this problem, using environmentally incompatible organic reagents or functionalized nanoparticles may greatly limit their wide applications. In this article, we report a method to visibly detect nitrite in less than 1 min at room temperature. The efficacy of the method relies on a specific reaction of HNO2 with H2O2 to produce peroxynitrous acid (HOONO), which oxidizes colorless 3,3',5,5'-tetramethylbenzidine (TMB) to its golden yellow diimine product in seconds, with the regeneration of HNO2. Therefore, HNO2 can be regarded as a catalyst for the oxidation of TMB by H2O2. Because color visualization of the TMB-H2O2 system (system I) is dependent upon the concentration of HNO2, it offers a unique avenue for the determination of nitrite. With this method, 1 μM of nitrite could be detected by the perception of yellow color in solution and less than 0.5 μM of nitrite be quantified with a spectrophotometer. The limit of detection (LOD) was 0.1 μM (S/N = 3). More interestingly, we found that the TMB-HNO2 system (system II) could be reversibly designed to detect H2O2 and then glucose with the help of glucose oxidase. We evaluated the applicability of the TMB-HOONO platform in the determination of nitrite in drinking water and urinary glucose, obtaining satisfactory results. Being sensitive, selective, time-efficient, and cost-effective, the two methods derived from the three-component reaction platform are feasible for quantification of nitrite and glucose in routine laboratory practice or rapid assay outside the laboratory.

Yang J.,Central South University | Yan D.,CAS Changchun Institute of Applied Chemistry | Jones T.S.,University of Warwick
Chemical Reviews | Year: 2015

Molecular template growth (MTG) is a newly developed method for fabricating high-quality organic semiconductor thin films with controllable morphologies, molecular orientations, electronic structures, and interface properties to produce high-performance organic electronic and optoelectronic devices. There are several MTG methods with different molecular template materials and growth behaviors, including multiphenyl- and multithiophene-based MTG, and perylene-derivative MTG. Extensive research works have also revealed that Individualized methods for fabricating high-quality organic semiconductor thin films with controllable thin-film properties can be developed on the basis of specific understandings of the growth behaviors of organic semiconductor molecules and the desired device structures.

Li C.,State University of New York at Stony Brook | Wang J.,State University of New York at Stony Brook | Wang J.,CAS Changchun Institute of Applied Chemistry
PLoS Computational Biology | Year: 2013

Cellular reprogramming has been recently intensively studied experimentally. We developed a global potential landscape and kinetic path framework to explore a human stem cell developmental network composed of 52 genes. We uncovered the underlying landscape for the stem cell network with two basins of attractions representing stem and differentiated cell states, quantified and exhibited the high dimensional biological paths for the differentiation and reprogramming process, connecting the stem cell state and differentiated cell state. Both the landscape and non-equilibrium curl flux determine the dynamics of cell differentiation jointly. Flux leads the kinetic paths to be deviated from the steepest descent gradient path, and the corresponding differentiation and reprogramming paths are irreversible. Quantification of paths allows us to find out how the differentiation and reprogramming occur and which important states they go through. We show the developmental process proceeds as moving from the stem cell basin of attraction to the differentiation basin of attraction. The landscape topography characterized by the barrier heights and transition rates quantitatively determine the global stability and kinetic speed of cell fate decision process for development. Through the global sensitivity analysis, we provided some specific predictions for the effects of key genes and regulation connections on the cellular differentiation or reprogramming process. Key links from sensitivity analysis and biological paths can be used to guide the differentiation designs or reprogramming tactics. © 2013 Li, Wang.

Li C.,State University of New York at Stony Brook | Wang J.,CAS Changchun Institute of Applied Chemistry
Journal of the Royal Society Interface | Year: 2013

Cellular differentiation, reprogramming and transdifferentiation are determined by underlying gene regulatory networks. Non-adiabatic regulation via slow binding/unbinding to the gene can be important in these cell fate decisionmaking processes. Based on a stem cell core gene network, we uncovered the stem cell developmental landscape. As the binding/unbinding speed decreases, the landscape topography changes from bistable attractors of stem and differentiated states to more attractors of stem and other different cell states as well as substates. Non-adiabaticity leads to more differentiated cell types and provides a natural explanation for the heterogeneity observed in the experiments. We quantified Waddington landscapes with two possible cell fate decision mechanisms by changing the regulation strength or regulation timescale (nonadiabaticity). Transition rates correlate with landscape topography through barrier heights between different states and quantitatively determine global stability. We found the optimal speeds of these cell fate decision-making processes. We quantified biological paths and predict that differentiation and reprogramming go through an intermediate state (IM1), whereas transdifferentiation goes through another intermediate state (IM2). Some predictions are confirmed by recent experimental studies. © 2013 The Author(s) Published by the Royal Society.

Li N.,Hanyang University | Zhang Q.,CAS Changchun Institute of Applied Chemistry | Wang C.,Hanyang University | Wang C.,Changzhou University | And 3 more authors.
Macromolecules | Year: 2012

Anion exchange membrane (AEM) materials were prepared from commercial polysulfone (PSf) by functionalization with tertiary amines via lithiation chemistry. By optimizing the reaction conditions, a degree of substitution (DS) of 0.81 could be achieved without evident polymer decomposition or cross-linking. The PSf containing pendent bis(phenyldimethylamine) substituents were then quaternized with CH 3I and ion exchange reaction to provide bis(phenyltrimethylammonium) (PTMA) polymer with hydroxide-conductive properties. Flexible and tough membranes with various ion exchange capacities (IEC)s could be prepared by casting the polymers from DMAc solutions. The ionomeric membranes showed considerably lower water uptake (less than 20%), and thus dimensional swelling in water, compared with many reported AEMs. The hydroxide conductivities of the membranes were above 10 mS/cm at room temperature. The unusually low water uptake and good hydroxide conductivity may be attributed to the "side-chain-type" structures of pendent functional groups, which facilitate ion transport. Although the PTMA substituents on the AEM were found to have insufficient long-term stability for alkaline fuel cell application, the investigation gives some insight and directions for polymeric designs by postfunctionalization. © 2012 American Chemical Society.

Xue L.,University of Osnabruck | Han Y.,CAS Changchun Institute of Applied Chemistry
Progress in Materials Science | Year: 2012

Strategies for the inhibition of dewetting of thin polymer films are reviewed. First, a brief introduction to the theory and the dynamics of dewetting of thin polymer films is given. Methods for the inhibition of dewetting of thin polymer films, including the modification of the substrate and the polymer, the cross-linking of the polymer and the addition of an additive as well as their mechanisms for inhibition are discussed. The chemical modification of the substrate or the polymer itself and the phase separation increase the thermodynamic stability of the system, while the cross-linking of the polymers reduces the mobility of the polymer chains, kinetically arresting the dewetting. The addition of an additive appears to thermodynamically and kinetically inhibit the dewetting. Finally, the future outlook in this research field is highlighted. © 2011 Elsevier Ltd. All rights reserved.

Wang W.,Jilin University | Ma D.,CAS Changchun Institute of Applied Chemistry | Gao Q.,Jilin University
IEEE Transactions on Electron Devices | Year: 2012

We demonstrated a low-operation-voltage pentacene organic thin-film transistor (OTFT) with an ultrathin polymer poly(methyl methacrylate co glycidyl methacrylate) as the gate dielectric layer. Under illumination, the threshold voltage (VT) continuously shifted positively, and the operation current (IDS) successively increased with the applied circular gate voltage (VG). After the light switchoff, both V T and $I \rm DS decayed to a metastable state and remained for a long time before decaying back to the initial value. This OTFT has a potential application in a photodetector with nonvolatile memory effect or in a memory by optical programming (P) and electrical erasing (E). The $I \rm DS was turned into a large value (one state) after P by a positive V G pulse under illumination and quickly returned to a small initial value (zero state) after E by a negative V G pulse. The present OTFT fabricated by a simple fabrication process exhibits a good practical foreground due to the low operation voltage and the good repeatability. © 2012 IEEE.

Chen Y.,Case Western Reserve University | Lin W.-C.,Case Western Reserve University | Liu J.,CAS Changchun Institute of Applied Chemistry | Dai L.,Case Western Reserve University
Nano Letters | Year: 2014

Tandem polymer solar cells (PSCs), consisting of more than one (normally two) subcells connected by a charge recombination layer (i.e., interconnecting layer), hold great promise for enhancing the performance of PSCs. For an ideal tandem solar cell, the open circuit voltage (Voc) equals to the sum of those of the subcells while keeping the short circuit current the same as the lower one, leading to an increased overall power conversion efficiency. The interconnecting layer plays an important role in regulating the tandem device performance. Here, we report that graphene oxide (GO)/GO-Cs (cesium neutralized GO) bilayer modified with ultrathin Al and MoO3 can act as an efficient interconnecting layer in tandem PSCs to achieve a significantly increased Voc, reaching almost 100% of the sum of the subcell V ocs under standard AM 1.5 conditions. © 2014 American Chemical Society.

Sun X.,CAS Changchun Institute of Applied Chemistry
Inorganic Materials | Year: 2010

In this letter a simple wet-chemical route was developed to prepare silver nanostructures. The for- mation of the silver nanostructures occurs in a single process, carried out by mixing an AgNO 3 aqueous solu- tion and a para-phenylenediamine solution at room temperature without the introduction of other reducing agents and morphology controlling agents. It is found that both the morphology and the size of such silver nanostructures can be facilely controlled by the molar ratio and concentration of the reactants as well as the solvent that was used to dilute para-phenylenediamine aqueous solution. As-formed silver nanostructures were examined by scanning electron microscopy. © Pleiades Publishing, Ltd., 2010.

Xu H.,CAS Changchun Institute of Applied Chemistry | Liu P.-T.,Changchun University of Science and Technology | Li Y.-H.,Changchun University of Science and Technology | Han F.-S.,Dalian University of Technology
Organic Letters | Year: 2013

An unprecedented protocol for the copper-mediated direct cyanation of aryl C-H by employing 2,2′-azobisisobutyronitrile (AIBN) as a free radical "CN" source is presented. The protocol not only provides a more efficient pathway for the synthesis of aryl nitriles in terms of the yields and the loading amount of copper salts but also, more importantly, represents a novel strategy for aryl C-H cyanation via a CN free-radical mechanism as compared to the CN anion-participating protocols often reported. © 2013 American Chemical Society.

Xu Z.,Shenyang University of Chemical Technology | Gao Y.,Shenyang University of Chemical Technology | Liu T.,Shenyang University of Chemical Technology | Wang L.,Shenyang University of Chemical Technology | And 2 more authors.
Journal of Materials Chemistry | Year: 2012

Well-dispersed, uniform Y 2O 3:Ln 3+ (Ln 3+ = Eu 3+, Tb 3+) hollow microspheres have been successfully prepared via a urea-assisted homogeneous precipitation method using polystyrene (PS) as templates, followed by a subsequent calcination process. X-Ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), photoluminescence (PL) spectra, and cathodoluminescence (CL) spectra were employed to characterize the samples. The results demonstrate that the samples can be well indexed to the pure cubic phase of Y 2O 3. The TEM and SEM images indicate that the shell of the uniform hollow spheres, whose diameter is about 2.1 μm, is composed of many uniform nanoparticles with diameters of around 20 nm. Upon ultraviolet (UV) and low-voltage electron beam excitation, the Y 2O 3:Ln 3+ (Ln 3+ = Eu 3+, Tb 3+) samples exhibit bright red (Eu 3+, 5D 0 → 7F 2), and green (Tb 3+, 5D 4 → 7F 5) luminescence. This material may find potential applications in light display systems, optoelectronic devices and drug delivery based on the uniform hollow structure, dimensions, and luminescence properties. Furthermore, this synthesis route may be of great significance in the preparation of other hollow spherical materials. © 2012 The Royal Society of Chemistry.

Chen K.,CAS Changchun Institute of Applied Chemistry | Xue D.,Dalian University of Technology
International Journal of Nanotechnology | Year: 2013

In this paper, we briefly review the recent research on crystallisation of cuprous oxide (Cu2O). Cu2O is an important semiconductor with cubic crystal structure and many applications in solar cell, catalysis, sensor, photonic crystals, etc. {100}, {111} and {110} surface structures of Cu2O are very important for controlling crystallisation. Different synthetic methods such as oxidation and reduction methods, together with different experimental parameters, size- and shape-controlled Cu2O crystals are summarised. The mechanisms underlying the crystallisation of Cu2O crystals are also highlighted. Our current work shows that Cu2O is a good model material to study crystallisation of inorganic materials. © 2013 Inderscience Enterprises Ltd. © 2013 Inderscience Enterprises Ltd.

Liao D.,University of Chinese Academy of Sciences | Chen J.,University of Chinese Academy of Sciences | Zhou H.,University of Chinese Academy of Sciences | Wang Y.,University of Chinese Academy of Sciences | And 2 more authors.
Analytical Chemistry | Year: 2013

A novel method for the sensing of acetylcholinesterase (AChE) activity and inhibitor screening based on the formation of metal coordination polymer has been developed. Acetylthiocholine (ATCh) was selected as the substrate. In the presence of AChE, ATCh was hydrolyzed to thiocholine and acetate. Thiocholine interacted with Ag(I) to form a metal coordination polymer. A positively charged perylene probe (probe 1) was employed. The fluorescence of probe 1 was very efficiently quenched by a polyanion [PVS, poly(vinyl sulfonate)]. In the presence of acetylcholinesterase, the positively charged metal coordination polymer newly formed in situ would interact with PVS, probe 1 monomer molecules were released, and a turn on fluorescence signal was detected. The assay is highly sensitive, a limit of detection of 0.04 mU/mL AChE was obtained. The assay is also highly selective, a number of potential interference proteins (enzymes) were tested, and none of them show noticeable interference. Sensing of AChE inhibitor was also demonstrated. Our assay is fairly simple and inexpensive. We envision that it could be used for the sensitive detection of other hydrolytic enzyme activities with properly selected substrates and for the screening of potential inhibitor drugs. © 2013 American Chemical Society.

Tian M.,Jilin University | Jia Q.,Jilin University | Liao W.,CAS Changchun Institute of Applied Chemistry
Journal of Rare Earths | Year: 2013

Synergistic solvent extraction of rare earth elements (REEs) from nitrate medium was investigated with mixtures of 8-hydroxyquinoline (HQ) and acidic organophosphorus extractants, bis(2,4,4-trimethylpentyl) dithiophosphinic acid (Cyanex 301) and bis(2,4,4-trimethylpentyl) monothiophosphinic acid (Cyanex 302). The extraction behavior of Cyanex 301/Cyanex 302 and their binary mixtures with HQ towards several lanthanoids (La, Nd, Sm, Tb, Ho, Tm) and yttrium (Y) was investigated. The separation ability of REEs was studied according to the various extraction effects. The extraction mechanisms for yttrium were studied with the methods of slope analysis and constant moles in the synergistic systems. The extracted compounds, the equilibrium constants, and thermodynamic functions were also determined.

Niu D.,Northeast Normal University | Yang J.,Northeast Normal University | Guo J.,Northeast Normal University | Kan W.-Q.,Northeast Normal University | And 3 more authors.
Crystal Growth and Design | Year: 2012

Twelve new metal-organic frameworks (MOFs), namely, [Cd(L)(H 2O)] (1), [Cd(L) 2Na 2]•H 2O (2), [Cd(L)(phen)] (3), [Cd(L)(phen)]•2H 2O (4), [Cd 2(L) 2(biim-2)]•H 2O (5), [Cd(L)(biim-4)]•2H 2O (6), [Co(L)(biim-4)]•H 2O (7), [Cd(L)(btp)] (8), [Cd(L)(btb)] (9), [Cd(HL)(bth) 0.5(H 2O)]•H 2O (10), [Co(HL)(btb) 0.5]•H 2O (11), and [Cd(L)(btbp) 1.5]•4H 2O (12), where phen = 1,10-phenathroline, biim-2 = 1,2-bis(imidazol-1′-yl)ethane, biim-4 = 1,1′-(1,4-butanediyl)bis(imidazole), btp = 1,3-bis(1,2,4-triazol-1-yl) propane, btb = 1,4-bis(1,2,4-triazol-1-yl)butane, bth = 1,6-bis(1,2,4-triazol-1- yl)hexane, btbp = 4,4′-bis(1,2,4-triazol-1-ylmethyl)biphenyl, and H 2L = (3-carboxyl-phenyl)-(4-(2′-carboxyl-phenyl)-benzyl) ether, have been synthesized under hydrothermal conditions. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Compound 1 features a two-dimensional (2D) layer, which is further stabilized by hydrogen bonds between the coordinated water molecules and adjacent carboxylate oxygen atoms. Compound 2 shows a 2D double layer with 3 6•4 6• 5 3 topology. Compounds 3 and 4 exhibit similar one-dimensional (1D) double chains, which are further extended into 2D supramolecular sheets and three-dimensional (3D) supramolecular frameworks through π-π interactions between pyridyl rings and phenyl rings, respectively. Compound 5 furnishes a 1D double chain, which is further extended into a 2D supramolecular layer via two kinds of π-π interactions. Compounds 6 and 7 are isostructural and display the same 2D undulated sheets with 4 4•6 2 topology. Compound 8 possesses a 2D sheet structure. Compound 9 displays 3D (3,4)-connected frameworks with (4•10 2)(4•10 3•12 2) topology. Compounds 10 and 11 possess similar 1D infinite chains, which are further linked via π-π interactions to generate 2D supramolecular layers. Compound 12 possesses a 2D double layer, which is further extended into a 3D supramolecular architecture through hydrogen-bonding interactions. The structural and topological differences of the 12 compounds indicate that the L anion and N-donor ligands play important roles in the formation of the final framework structures. The thermal behaviors of compounds 1, 3-4, 8-10, and 12 and luminescent properties of 1-6, 8-10, and 12 have also been investigated in detail. © 2012 American Chemical Society.

Wang Y.,City University of Hong Kong | Kalytchuk S.,City University of Hong Kong | Zhang Y.,City University of Hong Kong | Zhang Y.,Jilin University | And 4 more authors.
Journal of Physical Chemistry Letters | Year: 2014

Multicolor luminescent materials are of immense importance nowadays, while it still constitutes a challenge to achieve luminescence color tunability, transparency, and flexibility at the same time. Here we show how ultrasmall carbon dots (CDs) fluorescing strongly across the visible spectrum can be surface functionalized and incorporated into highly flexible hybrid materials by combination with ionic liquids within silica gel networks to form CD-ionogels with properties promising for fabrication of flexible displays and other optical technologies without the use of any toxic materials. We demonstrate how the emission from such hybrid materials can be tuned across a large range of the Commission Internationale de lEnclairage (CIE) display gamut giving full-color performance. We highlight how the rich ladder of emissive states attributable to organic functional groups and CD surface functionalization supports a smooth sequential multiple self-absorption tuning mechanism to red shift continuously from blue emitting n-π* transitions down through the lower energy states. © 2014 American Chemical Society.

Li W.,Jilin University | Liu D.,Jilin University | Shen F.,Jilin University | Ma D.,CAS Changchun Institute of Applied Chemistry | And 5 more authors.
Advanced Functional Materials | Year: 2012

In an organic electroluminescent (EL) device, the recombination of injected holes and electrons produces what appears to be an ion-pair or charge-transfer (CT) exciton, and this CT exciton decays to produce one photon directly, or relaxes to a low-lying local exciton (LE). Thus the full utilization of both the energy of the CT exciton and the LE should be a pathway for obtaining high-efficiency EL. Here, a twisting donor-acceptor (D-A) triphenylamine- imidazol molecule, TPA-PPI, is reported: its synthesis, photophysics, and EL performance. Prepared by a manageable, one-pot cyclizing reaction, TPA-PPI exhibits deep-blue emission with high quantum yields (90%) both in solution and in the solid state. Fluorescent solvatochromic experiments for TPA-PPI solutions show a red-shift of 57 nm (3032 cm -1) from low-polarity hexane (406 nm) to high-polarity acetonitrile (463 nm), accompanied by the gradual disappearance of the vibrational band in the spectra with increased solvent polarity. The photophysical investigation and DFT analysis suggest an intercrossed CT and LE excited state of the TPA-PPI, originating from its twisting D-A configuration. This is a rare instance that a CT-state material shows highly efficient deep-blue emission. EL characterization demonstrates that, as a deep-blue emitter with CIE coordinates of (0.15, 0.11), the performance of a TPA-PPI-based device is rather excellent, displaying a maximum current efficiency of >5.0 cd A -1, and a maximum external quantum efficiency of >5.0%, corresponding to a maximum internal quantum efficiency of >25%. The effective utilization of the excitation energy arising from materials with intercrossed-excited-state (LE and CT) characters is thought to be beneficial for the improved efficiency of EL devices. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ghosh K.R.,Carleton University | Saha S.K.,Carleton University | Wang Z.Y.,Carleton University | Wang Z.Y.,CAS Changchun Institute of Applied Chemistry
Polymer Chemistry | Year: 2014

A fluorescence sensory polymer (P1) consisting of pentiptycene and tetraphenylethene (TPE) units linked by acetylene was synthesized for direct detection of explosives in solution and air. At the same time, the effectiveness of thicker film in the presence of the TPE moiety for the detection of explosives was investigated. Fluorescence turn-off detection of picric acid (PA) was carried out in H2O-THF mixture containing 90% water, where the TPE units of the polymer are in a highly emissive aggregation state. Polymer P1 exhibits a fluorescence quenching response of 24% with addition of 4.36 × 10-8 M PA and 98% with the PA concentration at 4.7 × 10 -6 M. For a thinner film (4 nm) of P1 after exposure to dinitrotoluene for 10 s, the fluorescence intensity dropped 48% and it continued to drop 97% after 300 s, the corresponding values being 29% and 72% for thicker film (75 nm), respectively. These results indicate that P1 is a promising material for direct detection of nitro explosives in air and solution at ppb levels, and the TPE moiety inside the polymer improves the sensitivity and effectiveness of thicker films. © 2014 the Partner Organisations.

Yang P.,Nanyang Technological University | Teng X.,Nanyang Technological University | Lin J.,CAS Changchun Institute of Applied Chemistry | Huang L.,Nanyang Technological University
Journal of Materials Chemistry | Year: 2011

A novel bifunctional composite, combining the mesoporous structure of MCM-48 and the self-activated strong blue luminescence of hydroxyapatite (HAp), was synthesized and employed for drug delivery and in vitro drug release monitoring in the simulated body fluid (SBF) system. Studies have shown that this spherical composite exhibits ordered mesoscale pores, which are suitable to be a carrier for controlled drug release. Drug storage/release test indicates that this composite shows high drug loading and well controlled release capability for captopril (CapH2). Particularly, the composite loaded with CapH2 still shows strong blue emission centered at 410 nm under UV excitation, and the luminescence intensity keeps increasing when drug molecules are gradually released from the composite, which shows great potential for controlled drug delivery, in vivo monitoring, and disease diagnosis. © 2011 The Royal Society of Chemistry.

Hao W.,Carleton University | McBride A.,Carleton University | McBride S.,Carleton University | Gao J.P.,Carleton University | And 2 more authors.
Journal of Materials Chemistry | Year: 2011

A highly efficient colorimetric and fluorescence turn-on molecular probe for sensitive and selective detection of biologically important cysteine (Cys) in human plasma is demonstrated using a new zwitterionic dye (M1). The sensing mechanism involves release of the blue-colored and fluorescent M1 from its non-fluorescent, pale-yellow copper complex (M1-Cu) upon exposure to Cys. The new dye has the desired properties suitable for bio-sensing applications, such as distinct blue color, near-infrared (NIR) fluorescence at the wavelength of 875 nm, a large Stokes shift (195 nm), high solubility and stability. This new probe shows both colorimetric and fluorescent responses specifically to Cys over other naturally occurring amino acids, amines and some bioactive thiols and allows for detection of Cys in aqueous solution with a low detection limit of 4.07 × 10-6 M and in human plasma at the physiologically relevant levels. © 2011 The Royal Society of Chemistry.

Zhao C.,Jilin University | Lin H.,Jilin University | Zhang Q.,CAS Changchun Institute of Applied Chemistry | Na H.,Jilin University
International Journal of Hydrogen Energy | Year: 2010

Sulfonated poly(arylene ether ketone) bearing carboxyl groups (SPAEK-C) membranes were first modified by alternating deposition of oppositely charged polyaniline (PANI) and phosphotungstic acid (PWA) via the layer-by-layer method in order to prevent the crossover of methanol in a direct methanol fuel cell. The methanol permeability of SPAEK-C-(PANI/PWA)5 is 2 orders of magnitude less than those of Nafion 117 and pristine SPAEK-C. Furthermore, the modified membrane shows a proton conductivity of 0.093 Scm-1 at 25 °C and 0.24 Scm-1 at 80 °C, which are superior to those of Nafion 117 and pristine SPAEK-C. Fourier transform infrared spectroscopy confirms that PANI and PWA are assembled in the multilayers. The SEM images show the presence of thin PANI/PWA layers coated on the SPAEK-C membrane. Thermal stability, water uptake, water swelling, proton and electron conductivity at different temperature of the SPAEK-C and SPAEK-C-(PANI/PWA)n membranes are also investigated. © 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

Gao L.,Zhejiang University | Xu D.,CAS Changchun Institute of Applied Chemistry | Zheng B.,Zhejiang University
Chemical Communications | Year: 2014

A bolaamphiphilic low-molecular-weight gelator based on crown ether, which could self-assemble into organogels and hydrogels, was prepared. The contribution of each part of the structure to the gelation property was investigated by designing a series of analogues. A simple framework (crown ether-hydrophobic linkage-ammonium salt) was proposed. This journal is © the Partner Organisations 2014.

Zhang Y.,Japan National Institute of Materials Science | Fugane K.,Japan National Institute of Materials Science | Mori T.,Japan National Institute of Materials Science | Niu L.,CAS Changchun Institute of Applied Chemistry | Ye J.,Japan National Institute of Materials Science
Journal of Materials Chemistry | Year: 2012

The oxygen reduction reaction (ORR) is one of the important reactions not only in life processes but also in artificial energy conversion systems, such as fuel cells and metal/air batteries. As one of the non-precious ORR catalysts, N-doped carbon materials show an exciting activity, but most of them were universally synthesized by high-temperature pyrolysis or annealing up to 1100 °C in the past few decades, which makes the structural manipulation of the catalysts extremely difficult. Here, we propose that ORR active N-doped carbon catalysts could, in principle, be prepared via a sophisticated wet chemical reaction between a reactive graphitic carbon template (e.g. graphene oxide) and N-containing molecules (e.g. dicyandiamide) at temperatures as low as 180 °C. Without any high-temperature treatments, for example, the as-prepared N-doped reduced graphene oxide with additional Fe-containing nanoparticles showed an impressive ORR catalytic activity that was comparable to many previous N-doped carbon from high-temperature pyrolysis. Rational utilization of the graphitic carbon template, the N-containing molecules, and the wet chemical reactions may offer a low-temperature route to create interesting ORR electrocatalysts with easier surface properties manipulation. © The Royal Society of Chemistry 2012.

Hong G.-Y.,CAS Changchun Institute of Applied Chemistry
Rengong Jingti Xuebao/Journal of Synthetic Crystals | Year: 2015

Rare earth luminescent materials have been widely used in many fields and have become one of the major areas of rare earth application. This review has summarized recent progress on the study of rare earth phosphors for white LED, rare earth light conversion material, upconversion luminescent materials, rare earth luminescent nanomaterials, vacuum ultraviolet luminescent materials, lanthanide-complexes-based electroluminescent materials and rare earth scintillators and prospects the future development trend. © 2015, Chinese Ceramic Society. All right reserved.

Hardin B.E.,Stanford University | Sellinger A.,Stanford University | Moehl T.,Ecole Polytechnique Federale de Lausanne | Humphry-Baker R.,Ecole Polytechnique Federale de Lausanne | And 5 more authors.
Journal of the American Chemical Society | Year: 2011

Cosensitization of broadly absorbing ruthenium metal complex dyes with highly absorptive near-infrared (NIR) organic dyes is a clear pathway to increase near-infrared light harvesting in liquid-based dye-sensitized solar cells (DSCs). In cosensitized DSCs, dyes are intimately mixed, and intermolecular charge and energy transfer processes play an important role in device performance. Here, we demonstrate that an organic NIR dye incapable of hole regeneration is able to produce photocurrent via intermolecular energy transfer with an average excitation transfer efficiency of over 25% when cosensitized with a metal complex sensitizing dye (SD). We also show that intermolecular hole transfer from the SD to NIR dye is a competitive process with dye regeneration, reducing the internal quantum efficiency and the electron lifetime of the DSC. This work demonstrates the general feasibility of using energy transfer to boost light harvesting from 700 to 800 nm and also highlights a key challenge for developing highly efficient cosensitized dye-sensitized solar cells. © 2011 American Chemical Society.

Liu Q.-Y.,Jiangxi Normal University | Liu Q.-Y.,CAS Fujian Institute of Research on the Structure of Matter | Wang W.-F.,Jiangxi Normal University | Wang Y.-L.,Jiangxi Normal University | And 3 more authors.
Inorganic Chemistry | Year: 2012

A sulfonate-carboxylate ligand, 4,8-disulfonyl-2,6-naphthalenedicarboxylic acid (H 4-DSNDA), and eight new lanthanide coordination polymers { [ P r 4 ( O H ) 4 ( D S N D A ) 2 ( H 2 O )1 2 ] ( H 2 O )1 0 } n ( 1 ), [ L n (H 2 -DSNDA) 0.5(DSNDA) 0.5(H 2O) 5] n (Ln = La(2), Nd(3), Sm(4), Eu(5), Gd(6), and Dy(7)), and {[Er(H-DSNDA)(H 2O) 4](H 2O)}n (8)have been synthesized. Detailed crystal structures of these compounds have been investigated. Compound 1 has a 3D framework featuring the unique cubane-shaped [Pr 4(μ 3-OH) 4] clusters and is a binodal 4,8-connected network with (4 16·6 12)(4 4·6 2) 2 topology. Compounds 2-7 are isostructural and have 2D layered structures. Compound 8 is also a 2D layer but belongs to different structural types. The luminescence behavior of compound Eu(5)shows that the π-rich aromatic organic ligands efficiently transfer the absorbed light energy to the Eu(III)ions, thus enhancing the overall luminescent properties of compound Eu(5). The magnetic properties of all compounds except for the diamagnetic La(2)compound have been investigated. In addition, elemental analysis, IR spectra, and thermogravimetric analysis of these compounds are also described. © 2012 American Chemical Society.

Li G.,Wuhan University | Tian Y.,Wuhan University | Zhao Y.,Wuhan University | Lin J.,CAS Changchun Institute of Applied Chemistry
Chemical Society Reviews | Year: 2015

Nowadays, phosphor converted white light-emitting diodes (pc-WLEDs) have been widely used in solid-state lighting and display areas due to their superior lifetime, efficiency, and reliability as well as significant reduction in power consumption. Phosphors are indispensable components of pc-WLED devices, and their luminescence properties determine the quality of WLED lighting and displays. In order to further achieve high luminous efficacy, chromatic stability, and color-rending properties in pc-WLEDs, much effort has been focused on improving current pc-WLED phosphors and developing novel pc-WLED phosphors recently. This review article concerns commonly used rare earth ion (Eu2+ and Ce3+) activated inorganic phosphors, highlighting the important effect of spectral tuning via local structural variations on improving the luminescence performance of phosphors. The main spectral tuning strategies are discussed in detail and summarized, including (1) doping level control; (2) cationic substitution; (3) anionic substitution; (4) cationic-anionic substitution; (5) the crystal-site engineering approach; (6) mixing of nanophases. © The Royal Society of Chemistry 2015.

Wang J.,Northeast Normal University | Han D.,CAS Changchun Institute of Applied Chemistry | Wang X.,Northeast Normal University | Qi B.,Northeast Normal University | Zhao M.,Jilin University
Biosensors and Bioelectronics | Year: 2012

Polyoxometalates (H 3PW 12O 40, H 4SiW 12O 40 and H 3PMo 12O 40) have been proven to possess intrinsic peroxidase-like activity for the first time, which can catalyze oxidation of the peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) by H 2O 2 to form a blue color in aqueous solution. Among them, H 3PW 12O 40 (PW 12) exhibits higher catalytic activity to TMB than natural enzyme HRP and other two POMs. In addition, H 3PW 12O 40/graphene exhibited higher activity than H 3PW 12O 40 in this catalytic oxidation reaction due to the effect of graphene in promoting the electron transfer between the substrate and catalyst. POMs/H 2O 2/TMB system provides a simple, accurate approach to colorimetric detection for H 2O 2 or glucose. The colorimetric method based on POMs showed good response toward H 2O 2 and glucose detection with a linear range from 1.34×10 -7 to 6.7×10 -5mol/L and 1×10 -7 to 1×10 -4mol/L, respectively. The results showed that it is a simple, cheap, more convenient, highly selective, sensitive, and easy handling colorimetric assay. © 2012 Elsevier B.V.

Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,Jilin University | Wang J.,State University of New York at Stony Brook
Advances in Physics | Year: 2015

We present a review of the recently developed landscape and flux theory for non-equilibrium dynamical systems. We point out that the global natures of the associated dynamics for non-equilibrium system are determined by two key factors: the underlying landscape and, importantly, a curl probability flux. The landscape (U) reflects the probability of states (P) () and provides a global characterization and a stability measure of the system. The curl flux term measures how much detailed balance is broken and is one of the two main driving forces for the non-equilibrium dynamics in addition to the landscape gradient. Equilibrium dynamics resembles electron motion in an electric field, while non-equilibrium dynamics resembles electron motion in both electric and magnetic fields. The landscape and flux theory has many interesting consequences including (1) the fact that irreversible kinetic paths do not necessarily pass through the landscape saddles; (2) non-equilibrium transition state theory at the new saddle on the optimal paths for small but finite fluctuations; (3) a generalized fluctuation-dissipation relationship for non-equilibrium dynamical systems where the response function is not just equal to the fluctuations at the steady state alone as in the equilibrium case but there is an additional contribution from the curl flux in maintaining the steady state; (4) non-equilibrium thermodynamics where the free energy change is not just equal to the entropy production alone, as in the equilibrium case, but also there is an additional house-keeping contribution from the non-zero curl flux in maintaining the steady state; (5) gauge theory and a geometrical connection where the flux is found to be the origin of the gauge field curvature and the topological phase in analogy to the Berry phase in quantum mechanics; (6) coupled landscapes where non-adiabaticity of multiple landscapes in non-equilibrium dynamics can be analyzed using the landscape and flux theory and an eddy current emerges from the non-zero curl flux; (7) stochastic spatial dynamics where landscape and flux theory can be generalized for non-equilibrium field theory. We provide concrete examples of biological systems to demonstrate the new insights from the landscape and flux theory. These include models of (1) the cell cycle where the landscape attracts the system down to an oscillation attractor while the flux drives the coherent motion on the oscillation ring, the different phases of the cell cycle are identified as local basins on the cycle path and biological checkpoints are identified as local barriers or transition states between the local basins on the cell-cycle path; (2) stem cell differentiation where the Waddington landscape for development as well as the differentiation and reprogramming paths can be quantified; (3) cancer biology where cancer can be described as a disease of having multiple cellular states and the cancer state as well as the normal state can be quantified as basins of attractions on the underlying landscape while the transitions between normal and cancer states can be quantified as the transitions between the two attractors; (4) evolution where more general evolution dynamics beyond Wright and Fisher can be quantified using the specific example of allele frequency-dependent selection; (5) ecology where the landscape and flux as well as the global stability of predator-prey, cooperation and competition are quantified; (6) neural networks where general asymmetrical connections are considered for learning and memory, gene self-regulators where non-adiabatic dynamics of gene expression can be described with the landscape and flux in expanded dimensions and analytically treated; (7) chaotic strange attractor where the flux is crucial for the chaotic dynamics; (8) development in space where spatial landscape can be used to describe the process and pattern formation. We also give the philosophical implications of the theory and the outlook for future studies. © 2015 Taylor & Francis.

Zhang M.,University of Western Australia | Yang H.,University of Western Australia | Liu Y.,University of Western Australia | Sun X.,Northeastern University China | And 2 more authors.
Carbon | Year: 2012

We report a new mechanism of hydrophobic ripening for the formation of carbonaceous spheres by the dehydration of saccharides in a hydrothermal aqueous environment using fructose as a model precursor material. We investigated the formation of carbonaceous spheres from fructose in aqueous solutions under hydrothermal conditions. The spheres were found to contain 65.7 wt.% C, 4.3 wt.% H and 30.0 wt.% O, implying incomplete dehydration of the fructose. The spheres, typically ranging between 400 nm and 10 μm in diameter, are found to be constructed entirely of primary particles of ∼5 nm. The chemical structure of the carbonaceous spheres and the chemical compositions of residual solutions were analysed using solid state and solution 13C nuclear magnetic resonance and Fourier transform infrared spectroscopy. Based on these results, a four-step mechanism for the formation and growth of carbonaceous spheres has been proposed. © 2011 Elsevier Ltd. All rights reserved.

Li Y.,Jilin Institute of Architecture and Civil Engineering | Han C.,CAS Changchun Institute of Applied Chemistry
Industrial and Engineering Chemistry Research | Year: 2012

Isothermal and nonisothermal cold crystallization behaviors of asymmetric poly(l-lactide) (PLLA)/poly(d-lactide) (PDLA) blends at PDLA loadings of 0-20 wt % were investigated in this work. Formation of the stereocomplex in the blends was confirmed by differential scanning calorimetry and wide-angle X-ray diffraction. For both neat PLLA and its blends, the overall isothermal cold crystallization rates increase with increasing crystallization temperature; moreover, the overall isothermal cold crystallization rates of PLLA are faster in the blends than in neat PLLA, indicative of the nucleating agent effect of the stereocomplex formed in the blends. Crystallization mechanism and crystal structure of PLLA remain unchanged despite the PDLA loading. For the nonisothermal cold crystallization, the crystallization process of PLLA is accelerated by increasing both heating rate and the PDLA loading up to 10 wt %. The Ozawa equation failed to fit the crystallization process, while the Tobin equation could describe it well in the relative degree of crystallization range of 0-75%. © 2012 American Chemical Society.

Ji S.,CAS Changchun Institute of Applied Chemistry | Ji S.,University of Wisconsin - Madison | Nagpal U.,University of Wisconsin - Madison | Liao W.,University of Wisconsin - Madison | And 3 more authors.
Advanced Materials | Year: 2011

Self-assembling sphere-forming block copolymers that normally adopt a hexagonal packing in thin films were directed to assemble on chemically patterned surfaces into their three-dimensional bulk-like body-centered cubic morphology; two-dimensional manufacturing-relevant patterns with square and rectangular symmetry could be derived from the films using molecular transfer printing at a resolution beyond the limits of current lithographic tools and materials. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

OH radicals as reactive oxygen species in an organism were applied to assay antioxidant capacity since the obtained results present high biological relevance. As a proper photocatalyst, titanium dioxide was employed to generate OH radicals under ultraviolet light irradiation. However, ultraviolet light can damage molecular probe (DNA or protein) during the detection of antioxidant capacity, which interferes with the results. In this article, a novel composite graphene oxide-titanium dioxide (GO-TiO2) nanostructure was synthesized, which can generate numerous OH radicals just under visible light irradiation. In addition, a novel electrochemical antioxidant capacity sensor was designed with GO-TiO2 composites as source of OH radicals and DNA as a molecular probe. Antioxidants were measured by using the suppression of the decline of reduction current of methylene blue used as an intercalating agent for DNA after irradiation and ̇ OH-mediated DNA damage. Using gallic acid (GA) as a mode antioxidant species, the detection of GA at levels as low as 0.85 mg L(-1) was possible. The antioxidant capacity of other antioxidants was also assayed. Finally, the novel sensor was applied to the determination of antioxidant capacity in tea.

Liu K.,Beijing University of Technology | Meng J.,CAS Changchun Institute of Applied Chemistry
Journal of Alloys and Compounds | Year: 2011

Microstructures and mechanical properties of the Mg-4Y-2Gd-0.4Zr alloy with Zn additions have been investigated. The investigation suggests that the mechanical properties of the alloys have been greatly improved after hot extrusion due to the refinement of microstructures, especially the elongations. The extruded Mg-4Y-2Gd-1.0Zn-0.4Zr alloy displays excellent tensile properties. The ultimate tensile strength and the yield tensile strength are 291 and 228 MPa, respectively, with an elongation of 28%. The additions of Zn have an obvious effect on refining microstructure of the extruded alloys, and the vicker hardness increases with increasing Zn additions. The age hardening responses of the extruded alloys have been investigated at 220 °C. These alloys display unobvious ageing hardness responses. © 2010 Elsevier B.V. All rights reserved.

Zhu J.,Dalian University of Technology | Xue D.,Dalian University of Technology | Xue D.,CAS Changchun Institute of Applied Chemistry
CrystEngComm | Year: 2014

We report an electrochemically modulated method for single crystal silver nanobelts with uniform thickness and width, which grow along the <110> direction with {111} facets. The procedure involves a crystallographically- oriented and interfacial kinetic controlled chemical reduction process by using a sacrificial cathode electrode with nanochannel templates. Silver nanobelt-bundle arrays are formed orientedly within nanochannels and can be easily dispersed into individual nanobelts by removing the template. These nanobelts exhibit two distinct surface plasmon resonances (SPR) at 456 and 980 nm, and show a strong spontaneous emission (SE) at 519 nm when excited by UV or blue light. These silver nanobelts with a quasi-two-dimensional planar nanostructure are an important material for surface plasmon resonance-based technology, which may open up many practical opportunities in the fields of optics, electronics and photoelectronics. © 2014 The Royal Society of Chemistry.

Wang W.,Jilin University | Ma D.,CAS Changchun Institute of Applied Chemistry | Pan S.,Jilin University | Yang Y.,Jilin University
Applied Physics Letters | Year: 2012

In this letter, the hysteresis mechanism of organic thin-film transistors (OTFTs) with polyvinyl alcohol (PVA) as gate dielectric is studied. By examining OTFTs with a blocking polymer layer between gate and PVA or between channel and PVA, we confirm that the origin of the hysteresis is caused by the holes injected from the gate and/or from the channel and trapped in the interface of pentacene/PVA and the PVA bulk. A method is proposed to reduce the hysteresis. As a result, a pentacene OTFT with free-hysteresis and high mobility of 1.8 cm 2/Vs is achieved by a triple-layer polymer dielectric at low-operating voltages. © 2012 American Institute of Physics.

Nakamura I.,CAS Changchun Institute of Applied Chemistry
Soft Matter | Year: 2014

We study the solvation of ion pairs in diblock copolymer melts. Our theory accounts for the size of the ions, the permanent dipole moment and the molecular polarizability of the monomers, the Kuhn length, the compressibility of the liquid mixtures, and the degrees of polymerization. We demonstrate that the electrostatic field near an ion pair causes marked, synergistic effects on the volume fractions of the two blocks and hence the dielectric function. In particular, we illustrate the oscillatory behavior of the dielectric function near an ion pair and the disparity of the dielectric functions between like and unlike charges. These results depend significantly on the chain length and Kuhn length of the diblock copolymers on the nanometer scale. © The Royal Society of Chemistry 2014.

Li Z.-W.,Jilin University | Sun Z.-Y.,CAS Changchun Institute of Applied Chemistry | Lu Z.-Y.,Jilin University
Journal of Physical Chemistry B | Year: 2010

We develop a novel mesoscale simulation model in order to study the hierarchical self-assembly of soft disklike particles in dilute solutions. In suitable solvent conditions, the soft anisotropic disklike particles first self-assemble into one-dimensional flexible threads, in accord with experiments. Then, intriguingly, the threads reversibly pack into flexible hexagonal bundles by decreasing the solvent quality. Hierarchical self-assembly of this type may be important to provide a strategy to create bundle structures by bottom-up self-assembly with a single type of soft and flexible building block and mimic the bundles commonly found in biological structures. © 2010 American Chemical Society.

Li D.,Liaoning University | Jia J.,CAS Changchun Institute of Applied Chemistry | Wang J.,Liaoning University
Talanta | Year: 2010

A bismuth-film modified graphite nanofibers-Nafion glassy carbon electrode (BiF/GNFs-NA/GCE) was constructed for the simultaneous determination of trace Cd(II) and Pb(II). The electrochemical properties and applications of the modified electrode were studied. Operational parameters such as deposition potential, deposition time, and bismuth ion concentration were optimized for the purpose of determination of trace metal ions in 0.10 M acetate buffer solution (pH 4.5). Under optimal conditions, based on three times the standard deviation of the baseline, the limits of detection were 0.09 μg L -1 for Cd(II) and 0.02 μg L -1 for Pb(II) with a 10 min preconcentration. In addition, the BiF/GNFs-NA/GCE displayed good reproducibility and selectivity, making it suitable for the simultaneous determination of Cd(II) and Pb(II) in real sample such as river water and human blood samples. © 2010 Elsevier B.V. All rights reserved.

CAS Changchun Institute of Applied Chemistry and Sichuan Sunfor Light Co. | Date: 2011-03-01

An Alternate Current (AC) white Light-Emitting Diode (LED) device is provided, which belongs to the technical field of white LED manufacturing. The problem to be solved by the present invention is to low-costly overcome a series of deficiencies such as the stroboflash of an AC driven LED, and the heat dissipation difficulty caused by an integrated packaging of multiple LEDs. A white LED unit includes an LED chip and a light emitting material that can emit light when being excited by the LED chip. The luminous lifetime of the light emitting material is 1-100 ms. The LED chip only comprises one PN junction. The light emitted by the LED chip is mixed with the light emitted by the light emitting material to form white light. The white LED unit is driven by AC with a frequency not more than 100 Hz. The white LED device of prevent invention uses the single PN junction chip, rather than the prior integrated packaged AC multi-LED chip.

CAS Changchun Institute of Applied Chemistry | Date: 2012-09-29

A method for extracting and separating a rare-earth element. Cations and anions in a quaternary ammonium ionic liquid extractant, that is, 2-ethylhexyl phosphate mono-2-ethylhexyl acrylate trialkyl methyl ammonium and phosphate di(2-ethylhexyl) phthalate trialkyl methyl ammonium, react with rare-earth ions to form neutral complex molecules, also, a collaborative effect and a competitive effect are present between the cations and the anions in the quaternary ammonium ionic liquid extractant in a rare-earth element extraction process, the separation factor for the rare-earth element is thus increased. The method for extracting and separating the rare-earth element provides good interfacial phenomena in the extraction process, does not generate emulsification, obviates the need for extractant saponification, and provides increased separation factor for rare-earth elements, and particularly increased separation factor for heavy rare-earth elements. In addition, the rare-earth element extraction and separation method is of reduced extraction acidity, of reduced stripping acidity, and of reduced acid consumption.

Sichuan Sunfor Light Co. and CAS Changchun Institute of Applied Chemistry | Date: 2015-04-30

The invention relates to a yellow light afterglow material and a preparation method thereof as well as an LED illuminating device using the same. The yellow light afterglow material comprises the chemical formula of aY

CAS Changchun Institute of Applied Chemistry | Date: 2012-04-10

The present invention provides a method for detecting biochemical oxygen demand. Active sludge, surface water, domestic waste water, or industrial waste water comprising microorganism is taken as a water sample with microorganism in the method provided by the present invention. The water sample with microorganism is cultivated to obtain a microorganism film. The blank water sample and the target water sample are made to pass through the microorganism film respectively. The dissolved oxygen reduction current values of the blank water sample and the target water sample are detected. The difference value between the dissolved oxygen reduction current value of the target water sample and that of the blank water sample is obtained. On the basis of the difference value and the predetermined standard curve, the biochemical oxygen demand of the target water sample is acquired. The method provided by the present invention adopts active sludge, surface water, domestic waste water, or industrial waste water comprising microorganism as the water sample with microorganism. The environmental adaptability of the prepared microorganism film is strong, so that one or more of tap water, well water, atmospheric water, or ground water may serve as medium to maintain the physiological activity with no need of providing a buffer solution system.

CAS Changchun Institute of Applied Chemistry | Date: 2012-09-11

The invention provides a metal alkoxide complex of Formula (I), wherein X, M, R1, R2, R3, m, n, y and z are as defined in the Description. The invention also provides a catalyst composition comprising the metal alkoxide complex and a hydroxy-containing compound, wherein the molar ratio of the metal alkoxide complex to the hydroxy-containing compound is 1:01-1000. The invention also provides a production method of poly-- caprolactone or polyactide, wherein an -caprolactone monomer or a lactide monomer is reacted in the presence of the metal alkoxide complex or catalyst composition to obtain poly--caprolactone or polylactide. The metal alkoxide complex and the catalyst composition thereof can be used to catalyze the synthesis of poly-- caprolactone or polylactide with a high efficiency. The molecular weight of polycaprolactone or polylactide can be controlled by the molar ratio of the metal alkoxide complex and the hydroxy-containing compound, and is adjustable in the range of 1000-600,000, and wherein the molecular weight distribution is from 1.03 to 1.50.

CAS Changchun Institute of Applied Chemistry | Date: 2013-02-26

The present invention relates to a process of separating and purifying thorium by solvent extraction, comprising: 1) mixing a thorium enrichment with an inorganic acid to produce a feed; 2) mixing a neutral phosphorus extractant with an organic solvent to obtain an organic phase; 3) extracting from the feed with the organic phase to obtain a loaded organic phase; 4) scrubbing the loaded organic phase with a scrubbing solution and then back-extracting thorium with a stripping solution to obtain a thorium solution; 5) mixing the thorium solution with an oxalate to obtain a precipitate, which is then sintered to obtain thorium oxide. The present process allows to increase the purity of thorium from 80%-99% to 99.99% or more with a yield of more than 98%.

Sichuan Sunfor Light Co. and CAS Changchun Institute of Applied Chemistry | Date: 2015-10-02

An Alternate Current (AC) white Light-Emitting Diode (LED) device is provided, which belongs to the technical field of white LED manufacturing. The problem to be solved by the present invention is to low-costly overcome a series of deficiencies such as the stroboflash of an AC driven LED, and the heat dissipation difficulty caused by an integrated packaging of multiple LEDs. A white LED unit includes an LED chip and a light emitting material that can emit light when being excited by the LED chip. The luminous lifetime of the light emitting material is 1100 ms. The LED chip only comprises one PN junction. The light emitted by the LED chip is mixed with the light emitted by the light emitting material to form white light. The white LED unit is driven by AC with a frequency not more than 100 Hz. The white LED device of prevent invention uses the single PN junction chip, rather than the prior integrated packaged AC multi-LED chip.

CAS Changchun Institute of Applied Chemistry | Date: 2010-09-27

The present invention provides a resin composition consisting of a functionalized polypropylene (PP) and a functionalized styrenic thermoplastic elastomer (TPS). The functionalized PP is a PP grafted with N-vinyl pyrrolidone (NVP) and glycidyl methacrylate (GMA), and the functionalized TPS is a TPS grafted with acrylamide or methacrylamide. The functionalized PP and the functionalized TPS are subjected to melt blending to obtain the resin composition with a slight cross-linking structure due to the reaction between GMA and acrylamide or methacrylamide, therefore the resin composition presents good physical properties. Besides, the resin composition without additional plasticizer or other small molecular organic compounds can be utilized in blood bags, blood transfusion and collection apparatuses, etc. Thus, it does not release small molecular substances which are of potential harm to human body during use.

Xu N.,CAS Changchun Institute of Applied Chemistry
Journal of mass spectrometry : JMS | Year: 2012

In this study, electrospray ionization mass spectrometry (ESI-MS) was used to investigate the binding interaction of six alkaloids with parallel intermolecular G-quadruplex [d(TGGGGT)](4), and five alkaloids including berberine, jatrorrhizine, palmatine, tetrandrine, and fangchinoline showed complexation with the target DNA. Relative binding affinities were estimated on the basis of mass spectrometric data. The slight differences in chemical structures of berberine, jatrorrhizine, and palmatine had little influence on their binding affinities to [d(TGGGGT)](4). Tetrandrine and fangchinoline selectively bound to [d(TGGGGT)](4) versus duplex DNA. Collision-induced dissociation (CID) experiments showed that the complexes with berberine, jatrorrhizine, and palmatine dissociated via strand separation and ligand retaining in the strand while the complexes with tetrandrine and fangchinoline were dissociated via ligand elimination. A comparison of dissociation patterns in CID experiments of complexes with the alkaloids to those with the traditional G-quadruplex DNA binders suggested an end-stacking binding mode for tetrandrine and fangchinoline and an intercalation binding mode for berberine, jatrorrhizine, and palmatine to the target DNA. The current work not only provides deep insight into alkaloid/[d(TGGGGT)](4) complexes and useful guidelines for design of efficient anticancer agents but also demonstrates the utility of ESI-MS as a powerful tool for evaluating interaction between ligand and quadruplex DNA. Copyright © 2012 John Wiley & Sons, Ltd.

CAS Changchun Institute of Applied Chemistry | Date: 2010-11-02

The invention provides a method for producing soluble neodymium chloride complex using neodymium chloride aqueous solution as raw material, thereby avoiding the use of anhydrous neodymium chloride, simplifying the synthesis process and reducing the cost for synthesizing neodymium chloride complex. The neodymium chloride complex produced by this method is soluble not only in polar solvent, but also in nonpolar solvent. Such neodymium chloride complex also has good dissolvability in aliphatic hydrocarbon solvent which has relatively weaker solution power, and even in aliphatic hydrocarbon solvent with 6 or less carbon atoms which has even lower solution power. Since neodymium chloride complex is soluble in aliphatic hydrocarbon solvent, its transportation may be conducted, which is convenient for industrial application and contributes to improve the utilization efficiency of rare earth.

Agency: Cordis | Branch: FP7 | Program: MC-IIFR | Phase: FP7-PEOPLE-2010-IIF | Award Amount: 11.25K | Year: 2013

ChemCatSusDe addresses some of the industrial and economical issues of our society: fossil fuel depletion, use of renewable resources derived from the biomass, environmentally friendly chemistry for a sustainable future. At its core lies the versatility of complexes of zinc, magnesium, calcium, strontium and barium (the so-called bio-metals): green catalysts able to perform both the polymerisation of cyclic esters and highly atom-efficient hydroelementation reactions will be designed. The objectives defined by the researcher and the host institution in Rennes are: - Synthesis of well-defined complexes of the large alkaline-earth (Ca, Sr, Ba). The coordination chemistry of these metals in the presence of chelating, mono-anionic ligands will be studied. Owing to the extreme oxophilic nature of these elements, these catalytic precursors are expected to display excellent activities. The same synthetic strategies will also be extended to the preparation of complexes of the smaller zinc and magnesium, which display an excellent compromise between stability and catalytic activity - Use of these complexes for the catalytic immortal ring-opening polymerisation of cyclic monomers derived from renewable bioresources for the production of biocompatible and/or biodegradable polymers. All catalysts will be used for the polymerisation of lactide and monomers such as morpholinediones and b- or g-valerolactones - Hydroelementation of terminal alkenes catalyzed by heteroleptic amido-alkaline-earth complexes. Catalysts for the 100% atom-efficient hydrosilylation, -phophination and -amination of unsaturated substrates will be prepared - Study of the stability and reactivity of the targeted heteroleptic complexes by theoretical calculations: the design of catalytic systems will be elaborated and/or optimized according to preliminary calculations or those based on experimental structural data. - Development of long-term collaborations between the host and return institutions

Liu M.,CAS Changchun Institute of Applied Chemistry | Liu M.,University of Chinese Academy of Sciences | Chen W.,CAS Changchun Institute of Applied Chemistry
Nanoscale | Year: 2013

Metal nanoclusters exhibit unusual optical and catalytic properties due to their unique electronic structures. Here, surfactant-free silver nanoclusters supported on carbon nanodots were synthesized through a facile and green approach with only glucose and AgNO3 as precursors and without any other protecting ligands and reducing agents. The hybrid nanoclusters exhibited enhanced blue fluorescence compared to the carbon nanodots. More importantly, the "surface-clean" silver nanoclusters have remarkable electrocatalytic performance towards oxygen reduction reaction (ORR) with the most efficient four-electron transfer process. Moreover, compared with commercial Pt/C catalyst, the Pt-free hybrid clusters showed comparable catalytic performance for ORR but much higher tolerance to methanol crossover. Such silver nanoclusters will provide broad applications in fluorescence-related areas and in fuel cells as an efficient Pt-free catalyst with low cost and high catalytic performance. © 2013 The Royal Society of Chemistry.

Chen K.,CAS Changchun Institute of Applied Chemistry | Xue D.,CAS Changchun Institute of Applied Chemistry
Physical Chemistry Chemical Physics | Year: 2014

An ex situ observation was made by XRD patterns, SEM and TEM images, as well as cyclic voltammogram curves of CuO/Cu integrated anodes for lithium ion batteries. For the first time, the existence of a Cu+ ion long-range transfer path was identified at the potential widow of 1.30-1.60 V during both charging and discharging processes. Both SEM and TEM images show that these nanowires networks hanging CuO nanoparticles provide a Cu+ diffusion path within our designed CuO/Cu integrated anode. This work provides new insights into the conversion reaction of inorganic anode materials, and can favor the development of high-performance conversion anodes for lithium-ion batteries. © 2014 the Partner Organisations.

Wang Z.,CAS Changchun Institute of Applied Chemistry | Wang Z.,University of Chinese Academy of Sciences | Jiang W.,CAS Changchun Institute of Applied Chemistry
Soft Matter | Year: 2010

A unique reversible transformation between toroidal and cylindrical assemblies was observed. Toroids can change to cylinders by elongation at higher temperature. Reversely, upon cooling rate these cylinders can form toroids through pathway of cylinder-sphere-vesicle-ring or the end-to-end connection. © 2010 The Royal Society of Chemistry.

Wei W.,CAS Changchun Institute of Applied Chemistry | Chen W.,CAS Changchun Institute of Applied Chemistry
International Journal of Smart and Nano Materials | Year: 2013

By using 2-mercapto-5-n-propylpyrimidine (MPP) as capping ligands, copper nanoclusters with different core sizes were prepared using a chemical reduction method. The as-prepared copper nanoclusters were loaded onto a glassy carbon electrode and their size effect on the electrocatalytic activity towards the oxygen reduction reaction (ORR) was investigated with electrochemical techniques in alkaline electrolyte. Cyclic voltammetric (CV) studies showed that the onset potential of ORR on smaller copper nanoclusters is more positive than that on larger copper nanoclusters. Compared to the larger clusters, higher current density of ORR was obtained using the smaller copper nanoclusters. These CV results indicate that the smaller Cu nanoclusters exhibit higher catalytic performance for ORR. In rotating-disk voltammetric studies, ORR on the synthesized MPP monolayer-protected copper nanoclusters is mainly dominated by a two-electron transfer pathway to produce H2O2. © 2013 Taylor & Francis Group, LLC.

Gong D.,Ningbo University | Wang B.,CAS Changchun Institute of Applied Chemistry | Jia X.,Chinese Institute of Urban Environment | Zhang X.,CAS Changchun Institute of Applied Chemistry
Dalton Transactions | Year: 2014

A family of cobalt complexes supported by a tridentate Schiff base ligand with a labile donor (O, S, N) as a pendant arm (Co1-Co12, formulated as CoL 2) were synthesized by the treatment of the corresponding ligands with cobalt acetate tetrahydrate. The resultant complexes were well characterized by elemental analysis, FT-IR, magnetic moment as well as EI-MS. The solid-state structures of Co7 and Co12 were determined by X-ray diffraction and both established a distorted octahedron geometry around the cobalt center. The butadiene polymerization capabilities of the 12 complexes were evaluated and compared in representative cases. Diethylaluminum chloride (AlEt2Cl) was found to be the compatible activator resulting in highly active catalysts for producing polybutadiene of 93.8-98.2% cis-1,4 enchainment with negligible 1,2-structure and trans-1,4 units. It appears that a certain degree of lability of the donor is beneficial for high catalytic activity, generally following the order of O > S > N, and the high cis-1,4 selectivity. Moreover, the remarkable thermal stability of these systems has been achieved: the catalytic systems have the ability of conducting a high level of active and selective polymerization, reaching an upper limit of polymerization temperature of about 70 °C. The enhanced catalytic performances were further rationalized by the established diene polymerization mechanism, which could shed light on developing highly selective and reactive industrially applicable catalysts with an enhanced thermal stability. © 2014 The Royal Society of Chemistry.

Lv R.,Harbin Engineering University | Yang P.,Harbin Engineering University | He F.,Harbin Engineering University | Gai S.,Harbin Engineering University | And 2 more authors.
Chemistry of Materials | Year: 2015

To integrate photothermal therapy (PTT) with chemotherapy for improved antitumor efficiency, we designed a novel multifunctional composite by attaching CuxS nanoparticles onto the surface of Y2O3:Yb/Er hollow spheres through a combined coprecipitation and subsequent hydrothermal route. By altering the initial pH values for the synthesis of precursors, the size and structure properties of the final composites can controllably be tuned. The conjugated folic acid (FA) makes the composite recognize the targeted cancer cells and the attached CuxS nanoparticles endow the composite with photothermal function. It is found that the release of doxorubicin (DOX) from the functional carrier could be triggered by both pH value and near-infrared (NIR) radiation. In particular, both PTT and chemotherapy can be simultaneously driven by 980 nm laser irradiation. The synergistic therapeutic effect based on PTT and chemotherapy can lead to low in vitro viability of 12.9% and highly strong inhibition of animal H22 tumor in vivo, which is superior to any individual therapy. Moreover, the composite exhibits the clear in vivo red up-conversion luminescence (UCL). This multifunctional nanocarrier can be applicable as bioimaging agent and effective antitumor agent for the synergistic interaction between PTT and the enhanced chemotherapy. © 2014 American Chemical Society.

He W.,CAS Changchun Institute of Applied Chemistry | Lu L.,CAS Changchun Institute of Applied Chemistry
Advanced Functional Materials | Year: 2012

Despite sustained effort over the years, the exploration of an effective strategy toward understanding the structure and properties of graphene oxide (GO) is still highly desirable. Herein, a facile route to revisit the structure of GO is demonstrated by elucidating its chemical-conversion process solely in the presence of ammonia. Such a strategy can contribute to settling some arguments in recent models of GO, and also offers a prerequisite to identify critical components that can act as ultraviolet absorbers (UVAs) in resulting dispersions of nitrogen-doped graphene sheets (NGSs). Inspired by this, for the first time, the performance of NGSs, serving as new-style UVAs, is investigated through directly assessing the effect of NGSs on the photofastness of azo dyes (Food Black). These studies reveal that, distinct from the common understanding, the as-prepared NGSs can dramatically enhance the photostability of Food Black under UV irradiation and exhibit greatly applied potential as a multifunctional UVA for new-generation inkjet inks that can simultaneously integrate the advantages of dye-based and pigment-based inks. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ju J.,CAS Changchun Institute of Applied Chemistry | Chen W.,CAS Changchun Institute of Applied Chemistry
Biosensors and Bioelectronics | Year: 2014

Heteroatom doping can drastically alter the electronic characteristics of graphene quantum dots (GQDs), thus resulting in unusual properties and related applications. Herein, we develop a simple and low-cost synthetic strategy to prepare nitrogen-doped GQDs (N-GQDs) through hydrothermal treatment of GQDs with hydrazine. The obtained N-GQDs with oxygen-rich functional groups exhibit a strong blue emission with 23.3% quantum yield (QY). Compared to GQDs, the N-GQDs exhibit enhanced fluorescence with blue-shifted energy. Due to the selective coordination to Fe3+, the N-GQDs can be used as a green and facile sensing platform for label-free sensitive and selective detection of Fe (III) ions in aqueous solution and real water samples. The N-GQDs fluorescence probe shows a sensitive response to Fe3+ in a wide concentration range of 1-1945μM with a detection limit of 90nM (s/N=3). Interestingly, it is also found that both dynamic and static quenching processes occur for the detection of Fe3+ by N-GQDs, while the quenching effect of Fe3+ on the fluorescence of GQDs is achieved by affecting the surface states of GQDs. © 2014 Elsevier B.V.

Huang J.,CAS Changchun Institute of Applied Chemistry | Ma D.,CAS Changchun Institute of Applied Chemistry
Applied Physics Letters | Year: 2014

Resistive memory devices with resistive switching characteristics were fabricated based on poly (3,4-ethylene-dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) doping with polyvinyl alcohol. It has been demonstrated that the resistive switching characteristics in the memory device was strongly dependent on the treatment of the polymer blend film by ultraviolet ozone (UV-ozone). The UV-ozone treated device exhibited improved performance with the ON/OFF current ratio of more than 102, and its ON and OFF states can be maintained over 96 h without deterioration. The resistive switching behavior in the UV-ozone treated device was attributed to the formation and rupture of the PEDOT:PSS filaments as well as the narrow conducting paths through the native oxide of aluminum. © 2014 AIP Publishing LLC.

Ottakam Thotiyl M.M.,University of St. Andrews | Freunberger S.A.,University of St. Andrews | Freunberger S.A.,University of Graz | Peng Z.,University of St. Andrews | And 4 more authors.
Nature Materials | Year: 2013

Rechargeable lithium-air (O2) batteries are receiving intense interest because their high theoretical specific energy exceeds that of lithium-ion batteries. If the Li-O2 battery is ever to succeed, highly reversible formation/decomposition of Li2O2 must take place at the cathode on cycling. However, carbon, used ubiquitously as the basis of the cathode, decomposes during Li2O2 oxidation on charge and actively promotes electrolyte decomposition on cycling. Replacing carbon with a nanoporous gold cathode, when in contact with a dimethyl sulphoxide-based electrolyte, does seem to demonstrate better stability. However, nanoporous gold is not a suitable cathode; its high mass destroys the key advantage of Li-O2 over Li ion (specific energy), it is too expensive and too difficult to fabricate. Identifying a suitable cathode material for the Li-O2 cell is one of the greatest challenges at present. Here we show that a TiC-based cathode reduces greatly side reactions (arising from the electrolyte and electrode degradation) compared with carbon and exhibits better reversible formation/decomposition of Li2O 2 even than nanoporous gold (>98% capacity retention after 100 cycles, compared with 95% for nanoporous gold); it is also four times lighter, of lower cost and easier to fabricate. The stability may originate from the presence of TiO2 (along with some TiOC) on the surface of TiC. In contrast to carbon or nanoporous gold, TiC seems to represent a more viable, stable, cathode for aprotic Li-O2 cells. © 2013 Macmillan Publishers Limited. All rights reserved.

Xu W.-S.,James Franck Institute | Sun Z.-Y.,CAS Changchun Institute of Applied Chemistry | An L.-J.,CAS Changchun Institute of Applied Chemistry
Soft Matter | Year: 2015

Structural relaxation in binary hard spherical particles has been shown recently to exhibit a wealth of remarkable features when size disparity or mixture composition is varied. In this paper, we test whether or not similar dynamical phenomena occur in glassy systems composed of binary hard ellipses. We demonstrate via event-driven molecular dynamics simulation that a binary hard-ellipse mixture with an aspect ratio of two and moderate size disparity displays characteristic glassy dynamics upon increasing density in both the translational and the rotational degrees of freedom. The rotational glass transition density is found to be close to the translational one for the binary mixtures investigated. More importantly, we assess the influence of size disparity and mixture composition on the relaxation dynamics. We find that an increase of size disparity leads, both translationally and rotationally, to a speed up of the long-time dynamics in the supercooled regime so that both the translational and the rotational glass transition shift to higher densities. By increasing the number concentration of the small particles, the time evolution of both translational and rotational relaxation dynamics at high densities displays two qualitatively different scenarios, i.e., both the initial and the final part of the structural relaxation slow down for small size disparity, while the short-time dynamics still slows down but the final decay speeds up in the binary mixture with large size disparity. These findings are reminiscent of those observed in binary hard spherical particles. Therefore, our results suggest a universal mechanism for the influence of size disparity and mixture composition on the structural relaxation in both isotropic and anisotropic particle systems. © The Royal Society of Chemistry 2015.

Lu Y.,CAS Changchun Institute of Applied Chemistry | Lu Y.,University of Chinese Academy of Sciences | Chen W.,CAS Changchun Institute of Applied Chemistry
Journal of Physical Chemistry C | Year: 2010

Nanoneedle-covered palladium-silver nanotubes were synthesized through a galvanic displacement reaction with Ag nanorods at 100 °C (PdAg-100) and room temperature (PdAg-25). Transmission and scanning electron microscopic measurements displayed that the synthesized PdAg nanotubes exhibit a hollow structure with a nanoneedle-covered surface, providing the perfect large surface area for catalytic reactions. The PdAg nanotubes formed at 100 °C exhibit a more uniform surface morphology than those obtained at room temperature. The high-resolution TEM, energy-dispersive X-ray analysis, and powder X-ray diffraction measurements indicated that the surface of the nanotubes is decorated with crystalline Pd nanoparticles with Pd(111) planes, and meanwhile, Ag and AgCl particles are dispersed in the inner space of the nanotubes. The electrocatalytic activity of the synthesized PdAg nanotubes toward formic acid oxidation was studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). With the same loading on a glassy carbon electrode, the PdAg-100 nanotubes show high catalytic activity and stability from the CV and chronoamperometric analyses, which may be ascribed to the annealing process of the nanotube surface structures at 100 °C. The reaction kinetics of the HCOOH oxidation on the PdAg nanotubes was then examined by EIS measurements. It was found that the impedance responses are strongly dependent on the electrode potentials. With the potential increasing, the reaction kinetics evolve from resistive to pseudoinductive and then to inductive behaviors. On the basis of the proposed equivalent circuits, the synthesized PdAg nanotubes exhibit a much lower (almost 3 orders of magnitude smaller) charge-transfer resistance (R CT, a characteristic quantity for the rate of charge transfer for the electrooxidation of formic acid) than that obtained at the Pt-based nanoparticles reported previously. It was also found that the RCT at the PdAg-100 nanorods is much smaller than that at the PdAg-25 nanorods, indicating the electron-transfer kinetics for formic acid oxidation at the PdAg-100 nanorods is much better facilitated. The present work highlights the application of the nanoneedle-covered PdAg nanotubes with high surface areas as anode electrocatalysts in fuel cells and the influence of surface structure on their catalytic activity. © 2010 American Chemical Society.

Yang D.,CAS Changchun Institute of Applied Chemistry | Ma D.,CAS Changchun Institute of Applied Chemistry
Journal of Materials Chemistry C | Year: 2013

Fast response organic photodetectors were developed based on a high mobility hole-transporting organic semiconductor 1,1-bis[(di-4-tolylamino) phenyl]cyclohexane (TAPC). The active layer was constructed by mixing TAPC with a high electron mobility C70 and sandwiched between TAPC and C70. This kind of planar-mixed heterojunction structure significantly enhanced the external quantum efficiency (EQE) and greatly suppressed the leakage current. When the TAPC concentration was 45% and the reverse bias voltage was -6 V, a high performance organic photodetector with a bandwidth exceeding 30 MHz was realized. Simultaneously, the device also showed a peak EQE value approaching 60%. When the TAPC concentration was 30% and the reverse bias voltage was -3 V, the dark current density of the photodetector was as low as 3 pA mm -2. Hence, a high detectivity organic photodetector with a maximum value of up to 2.5 × 1013 Jones was achieved with a corresponding EQE of 56%. The device also exhibited a constant responsivity over 6 orders. Given that the bandwidth and EQE of photodetectors are dependent on the mixing ratio of TAPC and C70, the performances can be adjusted according to the requirements of the specific applications. Relevant theory models were used to demonstrate the limitation factors in the bandwidth of organic photodetectors. Our study clearly reveals that the utilization of high mobility organic materials and the design of suitable device structures is necessary in constructing high bandwidth organic photodetectors with high external efficiency and low leakage current. © 2013 The Royal Society of Chemistry.

Xu C.,CAS Changchun Institute of Applied Chemistry | Qu X.,CAS Changchun Institute of Applied Chemistry
NPG Asia Materials | Year: 2014

Cerium oxide nanoparticles (CeONPs) have received much attention because of their excellent catalytic activities, which are derived from quick and expedient mutation of the oxidation state between Ce4 and Ce3. The cerium atom has the ability to easily and drastically adjust its electronic configuration to best fit its immediate environment. It also exhibits oxygen vacancies, or defects, in the lattice structure; these arise through loss of oxygen and/or its electrons, alternating between CeO2 and CeO2-x during redox reactions. Being a mature engineered nanoparticle with various industrial applications, CeONP was recently found to have multi-enzyme, including superoxide oxidase, catalase and oxidase, mimetic properties that produce various biological effects, such as being potentially antioxidant towards almost all noxious intracellular reactive oxygen species. CeONP has emerged as a fascinating and lucrative material in biological fields such as bioanalysis, biomedicine, drug delivery, and bioscaffolding. This review provides a comprehensive introduction to CeONP's catalytic mechanisms, multi-enzyme-like activities, and potential applications in biological fields. © 2014 Nature Publishing Group All rights reserved 1884-4057/14.

Yi F.-Y.,CAS Changchun Institute of Applied Chemistry | Zhang J.,CAS Fujian Institute of Research on the Structure of Matter | Zhang H.-X.,CAS Fujian Institute of Research on the Structure of Matter | Sun Z.-M.,CAS Changchun Institute of Applied Chemistry | Sun Z.-M.,CAS Fujian Institute of Research on the Structure of Matter
Chemical Communications | Year: 2012

A family of chiral porous metal-organic frameworks were synthesized through an unprecedented chiral transformation process only involving achiral components. This method may provide a new point of view to rationally design targeted chiral MOFs and may shed light on the symmetry breaking mechanism. © 2012 The Royal Society of Chemistry.

Zhang C.,CAS Changchun Institute of Applied Chemistry | Zhang C.,Hebei University | Lin J.,CAS Changchun Institute of Applied Chemistry
Chemical Society Reviews | Year: 2012

Luminescent materials have found a wide variety of applications, including information displays, lighting, X-ray intensification and scintillation, and so on. Therefore, much effort has been devoted to exploring novel luminescent materials so far. In the past decade, defect-related luminescent materials have inspired intensive research efforts in their own right. This kind of luminescent material can be basically classified into silica-based materials, phosphate systems, metal oxides, BCNO phosphors, and carbon-based materials. These materials combine several favourable attributes of traditional commercially available phosphors, which are stable, efficient, and less toxic, being free of the burdens of intrinsic toxicity or elemental scarcity and the need for stringent, intricate, tedious, costly, or inefficient preparation steps. Defect-related luminescent materials can be produced inexpensively and on a large scale by many approaches, such as sol-gel process, hydro(solvo)thermal reaction, hydrolysis methods, and electrochemical methods. This review article highlights the recent advances in the chemical synthesis and luminescent properties of the defect-related materials, together with their control and tuning, and emission mechanisms (solid state physics). We also speculate on their future and discuss potential developments for their applications in lighting and biomedical fields. This journal is © The Royal Society of Chemistry 2012.

Lu B.,CAS Changchun Institute of Applied Chemistry | Lu B.,University of Chinese Academy of Sciences | Tang J.,CAS Changchun Institute of Applied Chemistry
Dalton Transactions | Year: 2014

Ultrathin, two-dimensional (2D) nanosheets of layered transition-metal chalcogenides are theoretically and technologically intriguing. However, it still remains a great challenge to synthesize ultrathin nanosheets because of the lack of an intrinsic driving force for the anisotropic growth of 2D superposed microstructures. Here we demonstrate, for the first time to our knowledge, the in situ synthesis of large-scale ultrathin Sb2S 3 nanosheets on graphene sheets (G) by solvothermal method in a water-ethylene glycol mixed solvent. Owing to the synergetic chemical coupling effects between G and Sb2S3, Sb2S3-G hybrid nanosheets exhibit high catalytic performance for the degradation of methylene blue in the presence of H2O2. Moreover, it was found that the resulting Sb2S3-G shows good electrocatalytic activity towards hydrazine oxidation. This work not only offers a low-cost and high performance alternative technology for synthesizing sheet-like Sb2S3, but also opens the door toward the fabrication of varying types of metal sulfide-graphene nanomaterials that will have wide applications in catalysis, environmental, and new energy fields. © 2014 the Partner Organisations.

Xu Y.,CAS Changchun Institute of Applied Chemistry | Wang E.,CAS Changchun Institute of Applied Chemistry
Electrochimica Acta | Year: 2012

This review shows how magnetic micro/nano particles have made significant contributions in the developments of electrochemical and Ru(bpy) 3 2+ electrochemiluminescent biosensors, including immuno-, enzyme, DNA, aptamer ones. Reports published from 2007 to November 2011 have been covered herein. More importantly, different aspects of the biosensors such as modes of magnetic particles, detection and flow injection techniques, analytes and the corresponding sensitivity and sample matrix, as well as several noticeably prominent characteristics have been summarized and discussed in detail. Accordingly, research opportunities and future development trends in these areas are discussed. © 2012 Elsevier Ltd.

Feng H.,State University of New York at Stony Brook | Zhang K.,CAS Changchun Institute of Applied Chemistry | Wang J.,State University of New York at Stony Brook | Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,Jilin University
Chemical Science | Year: 2014

Transition state or Kramers' rate theory has been used to quantify the kinetic speed of many chemical, physical and biological equilibrium processes successfully. For non-equilibrium systems, the analytical quantification of the kinetic rate is still challenging. We developed a new transition state or Kramers' rate theory for general non-equilibrium stochastic systems with finite fluctuations. We illustrated that the non-equilibrium rate is mainly determined by the exponential factor as the weight action measured from the basin of attraction to the "saddle" or more accurately "global maximum" point on the optimal path rather than the saddle point of the underlying landscape as in the conventional transition state or Kramers' rate formula for equilibrium systems. Furthermore, the pre-factor of the non-equilibrium rate is determined by the fluctuations around the basin of attraction and "saddle" point along the optimal paths. We apply our theory for non-equilibrium rate to fate decisions in stem cell differentiation. The dominant kinetic paths between stem and differentiated cell basins are irreversible and do not follow the gradient path along the landscape. This reflects that the dynamics of non-equilibrium systems is not only determined by the landscape gradient but also the curl flux, suggesting experiments to test theoretical predictions. We calculated the transition rate between cell fates. The predictions are in good agreements with stochastic simulations. Our general rate and path formula can be applied to other non-equilibrium systems. © 2014 the Partner Organisations.

Wang Y.,Hebei University of Technology | Li H.,Hebei University of Technology | Feng Y.,Hebei University of Technology | Zhang H.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2010

(Figure Presented) (Figure Presented) A glowing endorsement: Arranging zeolite L crystals into luminescent macroscopic structures allows preparation of dense, homogeneous, well-oriented, stable, and highly organized functional monolayers (see picture). The color of the luminescence of the resulting layers can be fine-tuned by changing the type and number of lanthanide ions coordinated to the linker, the guest inside the channels of the zeolite host, and the excitation wavelength. © 2010 Wiley-VCH Verlag GmbH &. Co. KGaA,.

Wang B.,CAS Changchun Institute of Applied Chemistry | Wang B.,University of Chinese Academy of Sciences | Yu C.,CAS Changchun Institute of Applied Chemistry | Yu C.,University of Chinese Academy of Sciences
Angewandte Chemie - International Edition | Year: 2010

Figure Presented Sensitivity that won't break the bank: The addition of an anti-lysozyme DNA aptamer (a polyanion) to a cationic perylene probe that exists in aqueous solution as a mixture of the fluorescent free monomer and aggregate forms shifted the equilibrium and resulted in fluorescence quenching (see schematic representation). The subsequent introduction of lysozyme weakened DNA binding to the perylene aggregates and led to fluorescence recovery. © 2010 Wiley-VCH Verlag GmbH &. Co. KGaA,.

Wang Y.,CAS Changchun Institute of Applied Chemistry | Wang Y.,University of Chinese Academy of Sciences | Jiang X.,CAS Changchun Institute of Applied Chemistry
ACS Applied Materials and Interfaces | Year: 2013

A novel porous carbon nanosheet was successfully fabricated by a one-step annealing process with folic acid as the carbon source in the absence of any other reagents or templates. The product exhibited a large specific surface area and good porosity. Meanwhile, the carbon nanosheets as a metal-free catalyst showed a high electrocatalytic activity toward the oxygen reduction reaction (ORR) in alkaline solution, including superior onset and reduction potentials as well as a nearly four-electron pathway. © 2013 American Chemical Society.

Zhang X.,CAS Changchun Institute of Applied Chemistry | Wang H.,University of South Carolina | Su Z.,CAS Changchun Institute of Applied Chemistry
Langmuir | Year: 2012

A new synthetic strategy has been developed for the fabrication of Au-Ag bimetallic core-shell nanoparticles (NPs) using polyelectrolyte multilayers (PEMs) as unique nanoreactors. Bimetallic NPs composed of Au core and Ag shell were successively incorporated into PEMs by repeating anion/cation exchange/reduction cycle multiple times in a stepwise manner. The strategy described here allows for the facile preparation of Au@Ag core-shell NPs with well-controlled core and shell dimensions and geometrically tunable optical properties by simply varying the number of ion-exchange/reduction cycles in the PEM matrix. The strategy can be extended to synthesize in situ other core-shell NPs in polymer matrix. © 2012 American Chemical Society.

Liu Y.,Max Planck Institute of Colloids and Interfaces | Liu Y.,CAS Changchun Institute of Applied Chemistry | Lipowsky R.,Max Planck Institute of Colloids and Interfaces | Dimova R.,Max Planck Institute of Colloids and Interfaces
Langmuir | Year: 2012

We studied the interfacial tension between coexisting phases of aqueous solutions of dextran and polyethylene glycol. First, we characterized the phase diagram of the system and located the binodal. Second, the tie lines between the coexisting phases were determined using a method that only requires measuring the density of the coexisting phases. The interfacial tension was then measured by a spinning drop tensiometer over a broad range of polymer concentrations close to and above the critical point. In this range, the interfacial tension increases by 4 orders of magnitude with increasing polymer concentration. The scaling exponents of the interfacial tension, the correlation length, and order parameters were evaluated and showed a crossover behavior depending on the distance to the critical concentration. The scaling exponent of the interfacial tension attains the value 1.50 ± 0.01 further away from the critical point, in good agreement with mean field theory, but the increased value 1.67 ± 0.10 closer to this point, which disagrees with the Ising value 1.26. We discuss possible reasons for this discrepancy. The composition and density differences between the two coexisting phases, which may be taken as two possible order parameters, showed the expected crossover from mean field behavior to Ising model behavior as the critical point is approached. The crossover behavior of aqueous two-phase polymer solutions with increasing concentration is similar to that of polymer solutions undergoing phase separation induced by lowering the temperature. © 2012 American Chemical Society.

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.

Qian G.,Carleton University | Qi J.,CAS Changchun Institute of Applied Chemistry | Qi J.,University of Chinese Academy of Sciences | Davey J.A.,Carleton University | And 3 more authors.
Chemistry of Materials | Year: 2012

A family of pyrrolo[3,4-c]pyrrol-1(2H)-one (PPO) and 2,5-diazapentalene (DAP) chromophores and DAP-containing polymers were synthesized, and their optical and electrochemical properties were studied. PPO and DAP chromophores are readily obtained by chemical transformation of the lactam unit in diketopyrrolopyrrole (DPP) dyes and can be used as versatile building blocks for construction of a variety of conjugated low-band-gap compounds and polymers. In comparison with the DPP chromophores, PPO and DAP chromophores have narrower energy gaps and low-lying HOMO levels in the order DPP > PPO > DAP. Interestingly, the PPO and DAP chromophores exhibit unique visible and near-infrared halochromic and halofluoric properties. The emission spectrum of DAP-containing polymer 6d covers the telecommunication window including the wavelength of 1310 nm. The photodetector with a device configuration of ITO/PEDOT:PSS (35 nm)/active layer (100 nm)/Al (100 nm) was fabricated using a blend of polymer 6d and [6,6]-phenyl-C 61-butyric acid methyl ester (PC 61BM) in a weight ratio of 1:3 as the active layer and exhibited photocurrent spectral response from 400 to 1000 nm and the detectivity in an order of 10 11 Jones at 800 nm. © 2012 American Chemical Society.

Yang W.,CAS Changchun Institute of Applied Chemistry | Parker T.G.,Florida State University | Sun Z.-M.,CAS Changchun Institute of Applied Chemistry
Coordination Chemistry Reviews | Year: 2015

Uranium phosphonates, an important class of actinide-organic coordination polymers, exhibit an exceptionally diverse and broad range of crystal structures. A variety of structure topologies have been identified for hexavalent uranium phosphonates, including cage clusters, chains, ribbons and tubes, sheets, and three-dimensional frameworks. In contrast, only a handful of tetravalent uranium phosphonates are known. This review presents a comprehensive account of the crystal structures of uranium phosphonates and the various building units (e.g. discrete monomers, polymeric units, infinite chains, and sheets) that result from the numerous coordination modes of phosphonate ligands with uranium. © 2015 Elsevier B.V..

Zhu S.,Nankai University | Li Z.-W.,CAS Changchun Institute of Applied Chemistry | Zhao H.,Nankai University
Langmuir | Year: 2015

Patchy particles are a type of colloidal particles with one or more well-defined patches on the surfaces. The patchy particles with multiple compositions and functionalities have found wide applications from the fundamental studies to practical uses. In this research patchy micelles with thiol groups in the patches were prepared based on coassembly of free block copolymer chains and block copolymer brushes on silica particles. Thiol-terminated and cyanoisopropyl-capped polystyrene-block-poly(N-isopropylacrylamide) block copolymers (PS-b-PNIPAM-SH and PS-b-PNIPAM-CIP) were synthesized by reversible addition-fragmentation chain transfer polymerization and chemical modifications. Pyridyl disulfide-functionalized silica particles (SiO2-SS-Py) were prepared by four-step surface chemical reactions. PS-b-PNIPAM brushes on silica particles were prepared by thiol-disulfide exchange reaction between PS-b-PNIPAM-SH and SiO2-SS-Py. Surface micelles on silica particles were prepared by coassembly of PS-b-PNIPAM-CIP and block copolymer brushes. Upon cleavage of the surface micelles from silica particles, patchy micelles with thiol groups in the patches were obtained. Dynamic light scattering, transmission electron microscopy, and zeta-potential measurements demonstrate the preparation of patchy micelles. Gold nanoparticles can be anchored onto the patchy micelles through S-Au bonds, and asymmetric hybrid structures are formed. The thiol groups can be oxidized to disulfides, which results in directional assembly of the patchy micelles. The self-assembly behavior of the patchy micelles was studied experimentally and by computer simulation. © 2015 American Chemical Society.

Li M.,Changchun University of Technology | Sun G.,Changchun University of Technology | Yin P.,Changchun University of Technology | Ruan C.,CAS Changchun Institute of Applied Chemistry | Ai K.,CAS Changchun Institute of Applied Chemistry
ACS Applied Materials and Interfaces | Year: 2013

Vanadium pentoxide (V2O5) has attracted much attention for energy storage application because of its high Faradaic activity and stable crystal structure, which make it a promising electrode material for supercapacitors. However, the low electronic conductivity and small lithium-ion diffusion coefficient of V2O5 limit its practical applications. To overcome these limitations, a facile and efficient method is here demonstrated for the fabrication of V2O5/reduced graphene oxide (rGO) nanocomposites as electrode materials for supercapacitors. With this method, the reduction of graphene oxide can be achieved in a cost-effective and environmentally friendly solvent, without the addition of any other toxic reducing agent. Importantly, this solvent can control the formation of the uniform rodlike V2O5 nanocrystals on the surface of rGO. Compared to pure V2O5 microspheres, the V 2O5/rGO nanocomposites exhibited a higher specific capacitance of 537 F g-1 at a current density of 1 A g-1 in neutral aqueous electrolytes, a higher energy density of 74.58 Wh kg -1 at a power density of 500 W kg-1, and better stability even after 1000 charge/discharge cycles. Their excellent performances can be attributed to the synergistic effect of rGO and rodlike V2O 5 nanocrystals. Such impressive results may promote new opportunities for these electrode materials in high-energy-density storage systems. © 2013 American Chemical Society.

Wei W.,CAS Changchun Institute of Applied Chemistry | Qu X.,CAS Changchun Institute of Applied Chemistry
Small | Year: 2012

Graphene has attracted much attention in recent years due to its extraordinary electronic, optical, magnetic, thermal, and mechanical properties. Despite continuing theoretical and experimental success, the unique physical properties of graphene remain underused and underappreciated. The key challenge in harnessing of the unique properties of graphene is the difficulty of reliable manipulation of well-dispersed graphene. Chemical and physical functionalization of graphene has become a focus of especial interest, because they can not only stabilize, but also induce new properties of graphene. This review summarizes the intriguing physical properties of chemically oxidized and noncovalently modified graphene, and graphene-based nanocomposites with polymer matrices or nanoparticles. Along with introducing the physical properties of functionalized graphene, their potential applications in diverse research areas are discussed. Modulating graphene physics: The extraordinary physical properties of graphene can be manipulated through proper functionalization. In addition to stabilization of graphene's inherent properties, some intriguing new properties can be introduced through functionalization. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Lin J.,CAS Changchun Institute of Applied Chemistry | Li C.-X.,CAS Changchun Institute of Applied Chemistry
Faguang Xuebao/Chinese Journal of Luminescence | Year: 2011

The rare earth fluorides nano- and micro-materials as well as controlled morphologies, formation mechanisms and luminescence properties are studied in this paper. A facile, general, template-free and environmentally friendly hydrothermal methodology has been developed to prepare the whole rare earth fluorides nano- and microcrystals. Organic additive trisodium citrate plays double roles of coordination ligand and shape modifier in determining the morphologies of the final products. Through the precise tuning several critical parameters including F- sources (NaF, NH4F, NaBF4), pH value in the initial solution and the choice of organic additives, the whole rare earth fluorides with various compositions, crystal structures, uniform sizes and morphologies have been obtained easily, including REF3 (RE=La~Lu) as well as cubic and hexagonal phase NaREF4 (RE=Y, Yb, Lu). More importantly, for the first time, the controllable synthesis of ytterbium (or lutetium) fluoride compounds with diverse crystal phase and morphologies have been reported. The possible formation mechanisms for products with various architectures have been presented systematically. The photoluminescence properties of Eu3+, Tb3+-doped DC and Yb3+/Er3+, Yb3+/Tm3+ -codoped UC NaREF4 or REF3 have also been investigated in detail.

Li Y.,Rutgers University | Shi T.,CAS Changchun Institute of Applied Chemistry | An L.,CAS Changchun Institute of Applied Chemistry | Huang Q.,Rutgers University
Journal of Physical Chemistry B | Year: 2012

In protein-polysaccharide complex systems, how nonspecific interactions such as electrostatic and van der Waals interactions affect complex formation has not been clearly understood. On the basis of a coarse-grained model with the specificity of a target system, we have applied Monte Carlo (MC) simulation to illustrate the process of complex coacervate formation from the association of proteins and polysaccharides. The coarse-grained model is based on serum albumin and a polycation system, and the MC simulation of pH impact on complex coacervation has been carried out. We found that complex coacervates could form three ways, but the conventional association through electrostatic attraction between the protein and polysaccharide still dominated the complex coacervation in such systems. We also observed that the depletion potential always participated in protein crowding and was weakened in the presence of strong electrostatic interactions. Furthermore, we observed that the sizes of polysaccharide chains nonmonotonically increased with the number of bound proteins. Our approach provides a new way to understand the details during protein-polysaccharide complex coacervation at multiple length scales, from interaction and conformation to aggregation. © 2012 American Chemical Society.

Zheng L.,CAS Changchun Institute of Applied Chemistry | Zheng L.,University of Chinese Academy of Sciences | Han Y.,CAS Changchun Institute of Applied Chemistry | Han Y.,University of Chinese Academy of Sciences
Journal of Physical Chemistry B | Year: 2012

This work focuses on the structural exploration of micro-sized crystals based on a well-known methanofullerene, [6,6]-phenyl-C61-butyric acid methyl ester (PCBM). We have succeeded in producing PCBM crystals with the hexagonal symmetry through the liquid-liquid interfacial precipitation (LLIP) method. We found that smaller but more regular PCBM crystals tend to form in the oversaturated PCBM solutions with solvents of lower solubility for PCBM, such as tetrahydrofuran (THF) and 1,4-dioxane. The structure of the produced crystals also shows a dependence on the solvents, which can be attributed to the incorporation of different solvent molecules into PCBM crystals. Under thermal annealing, for the first time, we have observed a crystalline to crystalline phase transformation of these hexagonal PCBM crystals. Along with the phase transformation, the morphology of the crystals has also been transformed from the hexagon to long needles. In addition, the needlelike crystals arrange themselves with a relative angle of 60° to each other, which implies an intrinsic structural correlation between needlelike and hexagonal crystals. © 2012 American Chemical Society.

Li X.,CAS Changchun Institute of Applied Chemistry | Han Y.,CAS Changchun Institute of Applied Chemistry
Journal of Materials Chemistry | Year: 2011

Polymer antireflection (AR) coatings have considerable practical value and wide-ranging applications because of their ability to adhere to flexible substrates and because they lend themselves easily to large-area processing. Preparing a suitable polymer porous structure with tunable wavelength AR by a simple approach is a challenge. In the present study, an inhomogeneous porous polymer film with a dense skin and porous structure underneath was obtained by spin coating a micelle solution of polystyrene-block-poly(4-vinypyridine) (PS-b-P4VP) with tetrahydrofuran (THF) and dimethyl formamide (DMF). The film was then subjected to non-solvent-induced phase separation before it reached a dry state. The dense skin surface morphology was fixed because of the rapid evaporation of THF during the spin coating. In the subsequent non-solvent immersion, an inner nanoporous structure was formed because the DMF was replaced by the non-solvent (with similar solubility to DMF). The inhomogeneous porous polymer film showed tunable wavelength AR controlled by the film thickness and immersion time in the non-solvent. The film exhibited an excellent transmittance of 99.6% at visible light wavelengths (400-800 nm) and 99.2% transmittance at near-infrared light wavelengths (800-2000 nm). © 2011 The Royal Society of Chemistry.

Sun C.,CAS Changchun Institute of Applied Chemistry | Xue D.,CAS Changchun Institute of Applied Chemistry
Journal of Molecular Structure | Year: 2014

The hydrogen bonding nature during ADP crystallization is studied on the basis of anisotropic chemical bonding conditions in ADP crystal combined with in situ IR observation. The variations of hydrogen bonding nature of NH4+ and H2PO4- groups dominate the transformation from the free hydrated ionic state to crystalline state during ADP crystallization. Anisotropic ADP crystal morphology depends on the anisotropic chemical bonding conditions along [1 0 0] and [1 0 1] directions. ADP crystal morphologies with different H2 PO4-n (n = 1-8) clusters can be calculated on the basis of hydrogen bonding conditions and H2PO4-n cluster structures at the growth interface. Experimentally, in situ IR spectrum can record the breaking of P-O⋯H-O-H and H-N⋯H-O-H, and the formation of P-O⋯H-O-P and H-N⋯H-O-P hydrogen bonding during ADP crystallization. The present work provides a promising strategy to identify the chemical bonding nature during crystallization processes of molecular crystals from aqueous solution. © 2013 Elsevier B.V. All rights reserved.

Huang J.,Wuhan University | Sun N.,CAS Changchun Institute of Applied Chemistry | Yang J.,Wuhan University | Tang R.,Wuhan University | And 3 more authors.
Advanced Functional Materials | Year: 2014

Great efforts have been devoted to seek novel approaches for constructing blue fl uorescent materials, which is one of the most important prerequisites for the commercialization of OLEDs. In recent years, various outstanding luminogens with aggregation-induced emission characteristic exhibit promising applications as emitters, but blue AIE fl uorophores with excellent EL performance are still very scarce. Here, fi ve hole-dominated blue AIE molecules are demonstrated by adopting construction approaches of changing linkage modes and increasing intramolecular torsion together, with the aim to restrict conjugation lengths without sacrifi cing good EL data. Device results show that the novel synthesized materials could be applied as bifunctional materials, namely blue light-emitting and hole-transporting materials, with comparable EL efficiencies, and the ηC,max and ηext,max are up to 8.03 cd A-1 and 3.99% respectively, which is among the best EL performance for blue AIE luminogens. © 2014 Wiley-VCH Verlag GmbH & Co. KGaA.

Su M.,CAS Changchun Institute of Applied Chemistry | Su Z.,CAS Changchun Institute of Applied Chemistry
Macromolecules | Year: 2014

In this work, a solution of poly(ethylene oxide)-block-polystyrene (PEO-b-PS) block copolymer in an organic solvent was dispersed in water to form an emulsion in the presence of poly(acrylic acid) (PAA), which upon solvent evaporation produced micelles, and the "emulsion and solvent evaporation" process was studied. It was found that PAA interacted with the PEO corona of the micelles to reduce the curvature, transforming the aggregates from cylinders into vesicles when 1,2-dichloroethane was the solvent. However, when a more volatile solvent, dichloromethane, was used instead, cylindrical micelles were obtained. Even from 1,2-dichloroethane, cylinders were the predominant species when the initial solution concentration was higher (i.e., shorter evaporation process) or when PAA with a much higher molecular weight was used. On the basis of these observations, the interplay between the solvent evaporation rate and the mass transport and chain reorganization at the interface is discussed. In addition, some intermediate structures were observed, which provided insight into the assembly process. © 2014 American Chemical Society.

Xue L.,CAS Changchun Institute of Applied Chemistry | Xue L.,RWTH Aachen | Han Y.,CAS Changchun Institute of Applied Chemistry
Progress in Polymer Science (Oxford) | Year: 2011

Strategies for the utilization of dewetting of polymer thin film to fabricate ordered patterns are reviewed. After a brief introduction to the polymer thin film dewetting theory, simulation results of pattern formation induced by physically and chemically patterned substrates, and physical confinement are then summarized. Experimental results including the mechanisms behind and the conditions for good quality of pattern formation based on the dewetting of polymer thin film induced by physical, chemical heterogeneous substrates, topographic structure on film surface, physical confinement and the movement of three-phase line are then discussed. A short introduction to the application of fabricated patterns is also discussed. © 2010 Elsevier Ltd. All rights reserved.

Lin Y.,CAS Changchun Institute of Applied Chemistry | Zhang F.,Shanghai Normal University | Pan D.,CAS Changchun Institute of Applied Chemistry | Li H.,Shanghai Normal University | Lu Y.,University of California at Los Angeles
Journal of Materials Chemistry | Year: 2012

TiO 2/(ZnS) x(CuInS 2) 1-x nanocomposites were prepared from oleic acid-capped TiO 2 nanocrystals and alloyed (ZnS) x(CuInS 2) 1-x nanocrystals. Element mapping and transmission electron microscopy (TEM) results suggested that the nanocomposites exhibit homogeneous composition with uniform mesoporous structure. High photocatalytic activities driven by simulated solar light were achieved owning to their high surface area and efficient electron transfer from (ZnS) x(CuInS 2) 1-x to TiO 2. This work enables the synthesis of a large variety of photocatalysts from nanocrystal building blocks for various applications beyond photodegradation of organic pollutants. © 2012 The Royal Society of Chemistry.

Lin Y.,CAS Changchun Institute of Applied Chemistry | Zhang F.,Shanghai Normal University | Pan D.,CAS Changchun Institute of Applied Chemistry
Journal of Materials Chemistry | Year: 2012

A series of (ZnS) x(CuInS 2) 1-x hierarchical micro/nano-structured solid solutions with precisely controlled chemical composition were synthesized via a facile one-pot solvothermal method. ZnO, Cu 2O, and In(OH) 3 are used as the starting materials and dissolved in ethanol dithiocarbamic acid which is formed from CS 2 and ethanolamine in situ. The ethanol dithiocarbamic acid not only serves as a thermally-degradable ligand, but also acts as sulfur source during synthesis, and can be completely removed by a simple calcination process. As-prepared (ZnS) x(CuInS 2) 1-x microspheres have a hierarchical micro/nano structure composed of around 7 nm nanoparticles. These samples show excellent photocatalytic H 2 evolution activity under visible-light irradiation without any noble metal loading owing to their high surface area (as high as 101.6 m 2 g -1) and unique hierarchical structure. © 2012 The Royal Society of Chemistry.

Niu N.,Harbin Engineering University | Yang P.,Harbin Engineering University | He F.,Harbin Engineering University | Zhang X.,Harbin Engineering University | And 3 more authors.
Journal of Materials Chemistry | Year: 2012

Well-defined one-dimensional NaLuF 4:Yb 3+,Er 3+/Tm 3+/Ho 3+ microtubes and microrods were successfully prepared by a surfactant-free molten salt method for the first time. It is found that with the prolonged time, the phase of NaLuF 4 transforms from cubic to hexagonal, while the morphology changes from nanoparticles to microtubes then to microrods. Moreover, upon 980 nm laser diode (LD) excitation, white up-conversion (UC) light was successfully achieved by properly tuning the sensitizer (Yb 3+) concentration in the host matrix. The relative emission intensities of different emission colors in Yb 3+/Er 3+, Yb 3+/Tm 3+, and Yb 3+/Ho 3+ doped β-NaLuF 4 can be precisely adjusted in a broad range by tuning the Yb 3+ doping concentration. Consequently, effective UC emissions with multicolors and a strong white light can be realized in β-NaLuF 4:Yb 3+/Er 3+/Tm 3+, and β-NaLuF 4:Yb 3+/Tm 3+/Ho 3+ structures by the appropriate control of the emission intensity balance for the three blue, green, and red basic colors. UC mechanisms in the co-doping and tri-doping β-NaLuF 4 samples were analyzed in detail based on the emission spectra and the plot of luminescence intensity to pump power. The as-obtained abundant luminescence colors in a much wide region contribute themselves great potential applications in various fields. Furthermore, the paper also provides an effective and facile approach to gain a desired color by manipulating the sensitizer concentration. © The Royal Society of Chemistry 2012.

Aldred M.P.,Huazhong University of Science and Technology | Li C.,Huazhong University of Science and Technology | Zhang G.-F.,Huazhong University of Science and Technology | Gong W.-L.,Huazhong University of Science and Technology | And 4 more authors.
Journal of Materials Chemistry | Year: 2012

We report the synthesis of novel amorphous fluorene-based fluorophores that have been end-capped with tetraphenylethene (TPE). Although in the solid state the fluorophores show bright cyan fluorescence with high (68%) photoluminescence quantum efficiency (PLQE), strong fluorescence quenching is observed in solution with low PLQE values ranging from 0.3% to 2.1%. When the fluorophores were added to a 90% water-THF solvent mixture nanoparticles were formed, which was confirmed by Dynamic Light Scattering (DLS) and Atomic Force Microscopy (AFM). Subsequent fluorescence measurements reveal that all the fluorophores exhibit aggregation induced emission (AIE) with high PLQE (41%). We have carried out a comparative study of 5 fluorene-based TPE materials (F(1-5)TPE), in which the fluorene core is extended, and investigated their thermal, optical, electrochemical and electroluminescence properties. From fluorescence quantum yield data we have discovered that the AIE effect decreases as the fluorene core increases both in the nanoparticle and in the solid state. Thermal analysis reveals that all fluorophores are amorphous with high thermal stabilities. Potential application in solid state vapour sensing has been demonstrated using dichloromethane that shows "on" and "off" fluorescence behaviour. Finally, Organic Light Emitting Diodes (OLEDs) have been fabricated with device configuration ITO/PEDOT/F(1-5)TPE/TPBi/LiF/Al. The best OLED device that incorporates F1-TPE as the emitter exhibits a turn-on voltage of 5.8 V, L max = 1300 cd m -2, η P,max = 1 lm W -1 and η C,max = 2.6 cd A -1. © 2012 The Royal Society of Chemistry.

Zhu C.,CAS Changchun Institute of Applied Chemistry | Dong S.,CAS Changchun Institute of Applied Chemistry
Electroanalysis | Year: 2014

In recent years graphene (GN) received widespread attention owing to its extraordinary physical and chemical properties. Lately, considerate efforts have been devoted to explore potential applications of GN in life science, especially in disease-related diagnostics and detection. Especially, the coupling of electrochemical devices with the GN offers an excellent platform to realize the diagnostics and detection of nucleic acid, protein and cancer cells with high performance. This review focuses on the rising progress on GN-based nanomaterials as advanced electrochemical sensing devices for the detection of the above-mentioned targets. Future challenges and perspectives in this rapidly developing field are also discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ungur L.,Catholic University of Leuven | Lin S.-Y.,CAS Changchun Institute of Applied Chemistry | Tang J.,CAS Changchun Institute of Applied Chemistry | Chibotaru L.F.,Catholic University of Leuven
Chemical Society Reviews | Year: 2014

Single-molecule toroics (SMTs) are defined, by analogy with single-molecule magnets, as bistable molecules with a toroidal magnetic state, and seem to be most promising for future applications in quantum computing and information storage and use as multiferroic materials with magnetoelectric effect. As an interdisciplinary research area that spans chemistry, physics and material sciences, synthetic chemists have produced systems suitable for detailed study by physicists and materials scientists, while ab initio calculations have been playing a major role in the detection of toroidal magnetization and the advancement of this field. In this tutorial review, we demonstrate the research developed in the fascinating and challenging field of molecular-based SMTs with particular focus on how recent studies tend to address the issue of toroidal arrangement of the magnetic moment in these systems. Herein, nine typical SMTs are summarized, showing that the assembly of wheel-shaped complexes with the high symmetry of the molecule unit and strong intra-molecular dipolar interactions using strong anisotropy metal ions represents the most promising route toward the design of a toroidal moment. Furthermore, the linkage of such robust toroidal moment units with ferromagnetic type through appropriate bridging ligands enhances the toroidal magnetic moment per unit cell. This journal is © the Partner Organisations 2014.

Zhou L.,University of Hong Kong | Zhou L.,CAS Changchun Institute of Applied Chemistry | Kwok C.-C.,University of Hong Kong | Cheng G.,University of Hong Kong | And 2 more authors.
Optics Letters | Year: 2013

In this work, organic electroluminescent (EL) devices with double light-emitting layers (EMLs) having stepwise energy levels were designed to improve the EL performance of a red-light-emitting platinum(II) Schiff base complex. A series of devices with single or double EML(s) were fabricated and characterized. Compared with single-EML devices, double-EML devices showed improved EL efficiency and brightness, attributed to better balance in carriers. In addition, the stepwise distribution in energy levels of host materials is instrumental in broadening the recombination zone, thus delaying the roll-off of EL efficiency. The highest EL current efficiency and power efficiency of 17.36 cdA and 14.73 lmW, respectively, were achieved with the optimized double-EML devices. At high brightness of 1000 cdm2, EL efficiency as high as 8.89 cdA was retained. © 2013 Optical Society of America.

Chen K.,CAS Changchun Institute of Applied Chemistry | Xue D.,CAS Changchun Institute of Applied Chemistry
Functional Materials Letters | Year: 2014

Cu-based materials, including metal Cu and semiconductors of Cu 2O and CuO, are promising and important candidates toward practical electrochemical energy storage devices due to their abundant, low cost, easy synthesis and environmentally friendly merits. This review presents an overview of the applications of Cu-based materials in the state-of-art electrochemical energy storage, including both lithium-ion batteries and supercapacitors. The synthesis chemistry, structures and the corresponding electrochemical performances of these materials are summarized and compared. During chemical synthesis and electroactive performance measurement of Cu-based materials, we found that Cu-Cu2O-CuO sequence governs all related transformations. Novel water-soluble CuCl2 supercapacitors with ultrahigh capacitance were also reviewed which can advance the understanding of intrinsic mechanism of inorganic pseudocapacitors. The major goal of this review is to highlight some recent progresses in using Cu-based materials for electrochemical energy storage. © 2014 World Scientific Publishing Company.

Guo S.,CAS Changchun Institute of Applied Chemistry | Guo S.,University of Chinese Academy of Sciences | Guo S.,Brown University | Wang E.,CAS Changchun Institute of Applied Chemistry | Wang E.,University of Chinese Academy of Sciences
Nano Today | Year: 2011

Nobel metal nanomaterials (NMNs) with interesting physical and chemical properties are ideal building blocks for engineering and tailoring nanoscale structures for specific technological applications. Particularly, effectively controlling the size, shape, architecture, composition, hybrid and microstructure of NMNs plays an important role on revealing their new or enhanced functions and application potentials such as fuel cell and analytical sensors. This review article focuses on recent advances on controllable synthesis and fuel cell and sensing applications of NMNs. First, recent contributions on developing a wet-chemical approach for the controllable synthesis of noble metal nanomaterials with a rich variety of shapes, e.g. single-component Pt, Pd, Ag and Au nanomaterials, multi-component core/shell, intermetallic or alloyed nanomaterials, metal fluorescent nanoclusters and metal nanoparticles-based hybrid nanomaterials, are summarized. Then diversified approaches to different types of NMNs-based nanoelectrocatalysts with the aim to enhance their activity and durability for fuel cell reactions are outlined. The review next introduces some exciting push in the use of NMNs as enhanced materials or reporters or labels for developing new analytical sensors including electrochemical, colorimetric and fluorescent sensors. Finally, we conclude with a look at the future challenges and prospects of the development of NMNs. © 2011 Elsevier Ltd. All rights reserved.

Xu Y.,CAS Changchun Institute of Applied Chemistry | Xu Y.,Qingdao University | Liu J.,Qingdao University | Gao C.,Qingdao University | Wang E.,CAS Changchun Institute of Applied Chemistry
Electrochemistry Communications | Year: 2014

Carbon quantum dots (CQDs) related electrochemiluminescence (ECL) research from 2009 to July 2014 is reviewed. The synthesis, surface states, applications and corresponding reaction mechanism of CQDs containing carbon nanodots and graphene quantum dots in ECL studies are comprehensively summarized. Consequently, their research vacancies and the development prospects of these fields are discussed. © 2014 Published by Elsevier B.V.

Li G.,CAS Changchun Institute of Applied Chemistry | Li G.,Wuhan University | Lin J.,CAS Changchun Institute of Applied Chemistry
Chemical Society Reviews | Year: 2014

Nowadays there are several technologies used for flat panel displays (FPDs) and the development of FPDs with enhanced energy efficiency and improved display quality is strongly required. Field emission displays (FEDs) have been considered as one of the most promising next generation flat panel display technologies due to their excellent display performance and low energy consumption. For the development of FEDs, phosphors are irreplaceable components. In the past decade, the study of highly efficient low-voltage cathodoluminescent materials, namely FED phosphors, has become the focus of enhancing energy efficiency and realizing high-quality displays. This review summaries the recent progress in the chemical synthesis and improvement of novel, rare-earth and transition metal ions activated inorganic cathodoluminescent materials in powder and thin film forms. The discussion is focused on the modification of morphology, size, surface, composition and conductivity of phosphors and the corresponding effects on their cathodoluminescent properties. Special emphases are given to the selection of host and luminescent centers, the adjustment of emission colors through doping concentration optimization, energy transfer and mono- or co-doping activator ions, the improvement of chromaticity, color stability and color gamut as well as the saturation behavior and the degradation behavior of phosphors under the excitation of a low-voltage electron beam. Finally, the research prospects and future directions of FED phosphors are discussed with recommendations to facilitate the further study of new and highly efficient low-voltage cathodoluminescent materials. This journal is © the Partner Organisations 2014.

In this letter, we demonstrate for the first time the electrostatically driven assembly of (3-aminopropyl)triethoxysilane (APTES) and HAuCl4 in aqueous media into novel micrometer-scale supramolecular sheets and their subsequent transformation into small, stable APTES bilayer-capped gold nanoparticles through a thermal process. The nanoparticle formation mechanism is also discussed. © 2010 American Chemical Society.

Chen J.,Jilin University | Yi F.-Y.,CAS Changchun Institute of Applied Chemistry | Yu H.,Jilin University | Jiao S.,Jilin University | And 2 more authors.
Chemical Communications | Year: 2014

Detecting volatile amines is a significant topic in the quality control of food and medical diagnosis. We report the first Eu-coordination polymer (CP) as a sensory material for the detection of a class of amine vapors with high selectivity and rapid response. This journal is © the Partner Organisations 2014.

Zhang G.,Shanghai JiaoTong University | Fu Y.,CAS Changchun Institute of Applied Chemistry | Xie Z.,CAS Changchun Institute of Applied Chemistry | Zhang Q.,Shanghai JiaoTong University
Macromolecules | Year: 2011

A series of new isoindigo-based low banbap polymers, containing thiophene, thieno[3,2-b]thiophene and benzo[1,2-b:4,5-b′]dithiophene as donors, have been synthesized by Stille cross-coupling reaction. Their photophysical, electrochemical and photovoltaic properties have been investigated. These new polymers exhibit broad and strong absorption between 400 and 800 nm with absorption maxima around 700 nm. The HOMO energy levels of polymers vary between -5.20 and -5.49 eV and the LUMO energy levels range from -3.66 to -3.91 eV. The optical bandgaps of the polymers are optimized for solar cell applications and they are at about 1.5 eV. Polymer solar cells (PSC) based on these new polymers were fabricated with device structures of ITO/PEDOT:PSS/polymers: PC 71BM (1:2, w/w)/LiF/Al. The photovoltaic properties of the polymers have been evaluated under AM 1.5G illumination at 100 mW/cm2 with a solar simulator. The combination of broad absorption, optimal bandgap and well matched energy levels with those of PCBMs makes these isoindigo-based low bandbap polymers promising materials for photovoltaic applications. © 2011 American Chemical Society.

Li S.,CAS Changchun Institute of Applied Chemistry | Pan D.,CAS Changchun Institute of Applied Chemistry
Journal of Crystal Growth | Year: 2012

Cu 2SnSe 3 nanocrystals with a metastable zincblende and wurtzite structure have been successfully synthesized. The crystal structures were confirmed by means of X-ray diffraction and selected area electron diffraction. The lattice mismatch between Cu 2SnSe 3 and ZnSe is only 0.26%, thus homogeneously alloyed (ZnSe) x(Cu 2SnSe 3) 1-x nanocrystals could be synthesized. The band gaps of nanocrystals can be tuned in a wide range of 2.75 to 0.92 eV; however the bowing parameter as high as 19.1 eV for alloyed (ZnSe) x(Cu 2SnSe 3) 1-x nanocrystals was observed. These low cost and dispersible alloyed (ZnSe) x(Cu 2SnSe 3) 1-x nanocrystals with a targeted band gap have a high potential in thin film solar cells. © 2012 Elsevier B.V.

Wei G.,Friedrich - Schiller University of Jena | Xu F.,CAS Changchun Institute of Applied Chemistry | Li Z.,CAS Changchun Institute of Applied Chemistry | Jandt K.D.,Friedrich - Schiller University of Jena
Journal of Physical Chemistry C | Year: 2011

A facile and effective strategy to create carbon nanotube (CNT)-based platinum nanoparticle (PtNP) nanohybrids is reported in this work. First, we prepared toluene-soluble CNTs by modifying CNTs with a bifunctional linker, Z-glycine N-succinimidyl ester (Z-Gly-OSu), and then we synthesized superwater-soluble CNT-hemoglobin (HGB) hybrid nanofibers (about 5 mg/mL) by phase-transferring the Z-Gly-OSu-modified CNTs from toluene to HGB aqueous solution. The prepared CNT-HGB nanofibers were used as templates to bind PtCl6 2- ions by electrostatic interaction between proteins and negatively charged ions. CNT-PtNP nanohybrids were successfully synthesized by chemically reducing the PtCl6 2- ions with NaBH 4. The results indicate that PtNPs with uniform size and shape were created on the side wall of CNTs with high dispersion, and the loading of PtNPs on CNTs was improved with the increase of protein concentration used for the preparation of CNT-HGB nanofibers. A nonenzymatic amperometric sensor for highly sensitive and selective detection of glucose was successfully fabricated as demonstrating based on the synthesized CNT-PtNP nanohybrids. Under optimal conditions, selective detection of glucose in a linear concentration range of 28.0 μM-46.6 mM (R = 0.996) was obtained, which reveals a lower limit of detection and wider linear response compared to some previously reported glucose sensors. © 2011 American Chemical Society.

Zhang Y.,Liaoning University | Wang Y.,CAS Changchun Institute of Applied Chemistry | Jia J.,CAS Changchun Institute of Applied Chemistry | Wang J.,Liaoning University
Sensors and Actuators, B: Chemical | Year: 2012

We present a glucose sensor by modification of glassy carbon electrode (GCE) with graphene oxide (GO), NiO nanofibers (NiONFs) and Nafion (NA). NiONFs were prepared by the facile electrospinning technique followed by calcination. And GO was synthesized by Hummers method. The modified electrode was pretreated by the electrochemical reduction. The sensor was characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS). The sensor exhibited high sensitivity (1100 μ AmM -1 cm -2), fast response time (less than 5 s), low detection limit of 0.77 μM (S/N = 3), long term stability, and excellent anti-fouling ability for glucose determination. The sensor was further applied to detection of glucose in human blood serum sample, and the results accorded with those of commercial test. © 2012 Elsevier B.V. All rights reserved.

Xu D.,CAS Changchun Institute of Applied Chemistry | Craig S.L.,Duke University
Macromolecules | Year: 2011

The large amplitude oscillatory shear behavior of metallo-supramolecular polymer networks formed by adding bis-Pd(II) cross-linkers to poly(4-vinylpyridine) (PVP) in dimethyl sulfoxide (DMSO) solution is reported. The influence of scanning frequency, dissociation rate of cross-linkers, concentration of cross-linkers, and concentration of PVP solution on the large amplitude oscillatory shear behavior is explored. In semidilute unentangled PVP solutions, above a critical scanning frequency, strain hardening of both storage moduli and loss moduli is observed. In the semidilute entangled regime of PVP solution, however, strain softening is observed for samples with faster cross-linkers (kd ∼ 1450 s-1), whereas strain hardening is observed for samples with slower cross-linkers (kd ∼ 17 s-1). The mechanism of strain hardening is attributed primarily to a strain-induced increase in the number of elastically active chains, with possible contributions from non-Gaussian stretching of polymer chains at strains approaching network fracture. The divergent strain softening of samples with faster cross-linkers in semidilute entangled PVP solutions, relative to the strain hardening of samples with slower cross-linkers, is consistent with observed shear thinning/shear thickening behavior reported previously and is attributed to the fact that the average time that a cross-linker remains detached is too short to permit the local relaxation of polymer chain segments that is necessary for a net conversion of elastically inactive to elastically active cross-linkers. These and other observations paint a picture in which strain softening and shear thinning arise from the same set of molecular mechanisms, conceptually uniting the two nonlinear responses for this system. © 2011 American Chemical Society.

Jian Z.,CAS Changchun Institute of Applied Chemistry | Jian Z.,University of Chinese Academy of Sciences | Tang S.,Jilin University | Cui D.,CAS Changchun Institute of Applied Chemistry
Macromolecules | Year: 2011

By using the cationic lutetium allyl species (C 5Me 4-C 5H 4N)Lu(η 3-C 3H 5) 2 (1)/[Ph 3C][B(C 6F 5) 4], the copolymerization of isoprene (IP) with styrene (St) could be achieved in a full range of monomer feed ratios (10 mol %-90 mol %). The 13C NMR and DSC analyses, and the competitive polymerization ratios (r St = 3.1 vs r IP = 23.9) clearly revealed that the obtained IP-St copolymers were multiblocked microstructure with high cis-1,4-polyisoprene (PIP) units (80%) and crystalline syndiotactic polystyrene (sPS) sequences, which was in contrast to the copolymerization behavior of butadiene (BD) and St with the same system that afforded only diblock copolymer. Strikingly, the terpolymerization of St with IP and BD via coordination mechansim was realized for the first time with high conversions (74-85%) and high activities (111-144 kg (mol Lu h) -1). The 13C NMR spectroscopic analysis indicated that the resultant terpolymers were composed of perfect sPS blocks, high cis-1,4-PIP units (77.7%) and almost pure cis-1,4-polybutadiene (PBD) sequences (97.5%) arranged in multiblocked mode. The insertion rate of styrene monomer in the terpolymer could be tuned swiftly by changing its feed ratio. DSC curves suggested that these multiblock terpolymers had continuously variable but single T g and (or) T m values, which was different from the triblock IP-BD-St terpolymer having two distinct T g values (-105 and -57 °C) and one high T m value (265 °C). Such novel terpolymers could not be accessed by any other methods known to date. © 2011 American Chemical Society.

Wu Z.,CAS Changchun Institute of Applied Chemistry | Ma D.,CAS Changchun Institute of Applied Chemistry | Ma D.,South China University of Technology
Materials Science and Engineering R: Reports | Year: 2016

White organic light-emitting diodes (WOLEDs) are emerging as the most promising technology for the next-generation display and solid-state lighting applications owing to their merits of being high-efficiency, low-cost, easy-flexibility, and environment-friendly. In this review, we will discuss the fundamental working principles, the basics of exciton manipulation concepts, the architecture designs within the emissive region, the approaches to relieve the efficiency roll-off at high luminance, and the remaining challenges in all phosphorescent and hybrid WOLEDs. A comprehensive understanding of the exciton manipulation concept and the key factors dominating the WOLED performances is of great importance for advancing technological applications. We aim to provide an overview on the recent advances in WOLEDs with emphasis specifically on: (a) principles on how to manipulate singlet and triplet excitons for maximizing the exciton utilization efficiency; (b) exciton manipulation in all phosphorescent WOLEDs and hybrid WOLEDs based on conventional fluorophors or thermally activated delayed fluorescent emitters by finely designing the emitting layer architectures and selecting matched materials; and (c) strategies to mitigate the efficiency roll-off including the utilization of effective charge and exciton-confined structures, decreasing the exciton lifetime, reducing molecular aggregation, and broadening the exciton recombination zone. © 2016 Elsevier B.V.

Shan Y.,CAS Changchun Institute of Applied Chemistry | Shan Y.,Changchun University of Technology | Wang H.,CAS Changchun Institute of Applied Chemistry | Wang H.,University of Chinese Academy of Sciences
Chemical Society Reviews | Year: 2015

The cell membrane is one of the most complicated biological complexes, and long-term fierce debates regarding the cell membrane persist because of technical hurdles. With the rapid development of nanotechnology and single-molecule techniques, our understanding of cell membranes has substantially increased. Atomic force microscopy (AFM) has provided several unprecedented advances (e.g., high resolution, three-dimensional and in situ measurements) in the study of cell membranes and has been used to systematically dissect the membrane structure in situ from both sides of membranes; as a result, novel models of cell membranes have recently been proposed. This review summarizes the new progress regarding membrane structure using in situ AFM and single-molecule force spectroscopy (SMFS), which may shed light on the study of the structure and functions of cell membranes. © The Royal Society of Chemistry 2015.

Ding I.-K.,Stanford University