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Nanjing, China

Nanjing Tech University , colloquially known as Nan Gong Da , is a university located in Nanjing, Jiangsu Province, China. The university specializes in engineering. English language courses are compulsory. Wikipedia.

Yang L.,Nanjing Southeast University | Du K.,Nanjing Southeast University | Niu X.,Nanjing University of Technology | Li Y.,Nanjing Southeast University | Zhang Y.,Nanjing Southeast University
International Journal of Refrigeration | Year: 2011

Two types of nanofluids are obtained by adding the mixture of carbon black nanoparticles with emulsifier OP-10, and Al2O3 nanoparticles with sodium dodecyl benzene sulfonate (SDBS) in the ammonia-water solution, respectively. The dispersion stability of the prepared nanofluids in different mass fractions of surfactants is investigated by the light absorbency ratio index methods. The results show that with the increase of mass fraction of surfactant, the stability of carbon black nanofluid is improved firstly and then is exacerbated, while the stability of Al2O3 nanofluid is exacerbated firstly, then is improved, and then is exacerbated again. The influences of surfactant on the stability of ammonia-water nanofluids abide by the monolayer adsorption theory or electric double layer adsorption theory. Finally, the theoretical surfactant mass fractions required in the preparation of ammonia-water nanofluids are calculated by simplifying the dispersion models and the results are in accordance with experimental results. © 2011 Elsevier Ltd and IIR. All rights reserved.

Ding X.,Nanjing University of Science and Technology | Kong X.,Nanjing University of Science and Technology | Jiang J.,Nanjing University of Science and Technology | Cui C.,Nanjing University of Science and Technology | Guo L.,Nanjing University of Technology
International Journal of Hydrogen Energy | Year: 2010

The fabrication and electrochemical properties of graded La0.7Sr0.3CuO3-δ-Sm0.2Ce0.8O2-δ (LSCu-SDC) composite cathodes were investigated in this paper. The phase composition, microstructure and electrochemical properties of the electrodes were characterized using X-ray diffraction (XRD), electron microscopy, electrochemical impedance spectroscopy (EIS) and cathodic polarization examinations. The results showed that the triple-layer graded cathode had super electrochemical performance comparing with the monolayer cathode. The graded LSCu-SDC cathode showed a polarization resistance of 0.094 Ωcm2, a value much lower than the monolayer LSCu cathode of 0.234 Ωcm2 at 800 °C in air. The current density of the graded cathode was 0.341 A cm-2, more than double higher than monolayer LSCu of 0.146 A cm-2 at an overpotential of 30 mV. The improved electrochemical performance could be attributed to the improved physical and chemical compatibility of the cathode layers in graded compositions with SDC electrolyte as well as the enlargement of triple-phase boundary for oxygen reduction. © 2009 Professor T. Nejat Veziroglu.

Panesar D.K.,University of Toronto | Mo L.,University of Toronto | Mo L.,Nanjing University of Technology
Cement and Concrete Composites | Year: 2013

Research and development of low CO2 binders for building material applications is warranted in efforts to reduce the negative environmental impacts associated with the cement and concrete industry. The purpose of this study is to investigate the effect of carbonation curing on the mineralogy, morphology, microstructure and evolution of compressive strength of mortars comprised of general use (GU) cement, ground granulated blast furnace slag (GGBFS), and reactive MgO used as cement replacement. This study investigates binary (GU-MgO) and ternary (GU-GGBFS-MgO) blends exposed to atmosphere curing (0.0038%CO2) and carbonation curing (99.9%CO 2). Carbonation-cured mortars exhibited greater compressive strengths than atmosphere mortars at all ages (7 d, 28 d, and 56 d). Increasing percentages of reactive MgO decreased the compressive strength markedly less for carbonation-cured mortars than atmosphere-cured mortars particularly due to magnesium calcite formations. Magnesium calcite influenced the morphology of carbonates and promoted the carbonate agglomeration resulting in a dense and interconnected microstructure.

Ru J.,Nanjing University | Gao F.,Nanjing University | Wu T.,Nanjing University | Yao M.-X.,Nanjing University of Technology | And 2 more authors.
Dalton Transactions | Year: 2014

A pair of one-dimensional enantiomers based on the versatile chiral dicyanoruthenate(iii) building block have been synthesized and they are chiral single-chain magnets with the effective spin-reversal barrier of 28.2 K. © The Royal Society of Chemistry 2014.

Li W.-x.,Nanjing University of Technology | Li W.-x.,Nanjing University of Aeronautics and Astronautics | Li B.-y.,Nanjing University of Aeronautics and Astronautics
Expert Systems with Applications | Year: 2010

This paper present a new extension Promethee II method based on generalized fuzzy numbers. Considering the fuzziness in the decision data, linguistic variables that can be expressed in generalized fuzzy numbers are used, to assess the weights of all criteria and the ratings of each alternative with respect to each criterion. The proposed method considers the difference between each point in two interval numbers based on the α-cut of generalized fuzzy numbers, simultaneously, the defuzzified values, the height and the spreads of generalized fuzzy numbers, achieves the ranking order of every alternative. © 2010 Elsevier Ltd. All rights reserved.

Mo L.,University of Toronto | Mo L.,Nanjing University of Technology | Panesar D.K.,University of Toronto
Cement and Concrete Composites | Year: 2013

The cement industry and concrete producers are under pressure to reduce the carbon footprint and energy demands of cement-based construction materials. This study investigates the CO2 uptake of paste mixtures designed with general use (GU) Portland cement, ground granulated blast furnace slag (GGBFS) and reactive MgO as cement replacement due to exposure to an accelerated carbonation curing regime with 99.9% concentration of CO2. The CO2 uptake, carbonation mechanism, microstructure and microhardness of cement pastes are examined. Key outcomes revealed that: (i) samples exposed to accelerated carbonation curing exhibit a denser microstructure and higher microhardness in comparison to non-carbonated samples, (ii) irrespective of the presence of reactive MgO, CO2 uptake increases with age from 7 to 56 d, (iii) by 56 d, pastes containing 10% and 20% reactive MgO uptake similar amounts of CO2 in comparison to mixtures without reactive MgO, and (iv) pastes containing 40% reactive MgO uptake the least amount of CO 2 however, exhibit the greatest microhardness and the lowest porosity. © 2013 Elsevier Ltd. All rights reserved.

Wang Y.,Nanjing University of Technology
Accounts of Chemical Research | Year: 2016

ConspectusPores regulate the entry and exit of substances based on the differences in physical sizes or chemical affinities. Pore uniformity, ordering, and the homogeneity of the surface chemistry of the pore walls are vital for maximizing the performance of a porous material because any scattering in these parameters weakens the capability of pores to discriminate foreign substances. Most strategies for the creation of homogeneous pores are destructive, and sacrificial components in the precursor materials must be selectively removed to generate porosities. The incorporation and subsequent removal of the sacrificial components frequently make the pore-making process complicated and inefficient and impose greater uncertainty in the control of the pore homogeneity.Block copolymers (BCPs) have been demonstrated to be promising precursors in the fabrication of highly ordered nanoporous structures. Unfortunately, BCP-derived porosities are also predominantly dependent on destructive pore-making processes (e.g., etching or extraction). To address this problem, we have developed a swelling-based nondestructive strategy. In this swelling process, one simply needs to immerse BCP materials in a solvent selective for the minority blocks for hours. After removing the BCPs from the solvent followed by air drying, pores are generated throughout the BCP materials in the positions where the minority blocks initially dwell. This Account discusses our recent discoveries, new insights, and emerging applications of this burgeoning pore-making method with a focus on the development of ordered porosities in bulk BCP materials.The initial morphology and orientation of the minority phases in BCPs determine the pore orientation and geometry in the produced porous materials. For nonaligned BCPs, three-dimensionally interconnected pores with sizes scattering in the 10-50 nm range are produced after swelling. There is a morphology evolution of BCP materials from the initial nonporous structure to the increasingly opened nanoporous intermediates, to interconnected networks of micellar nanofibers, and finally to isolated micellar spheres with increasing degrees of swelling. When the BCP films are aligned perpendicularly or in-plane, selective swelling results in uniform "standing" (perpendicular orientation) and "sleeping" (in-plane orientation) pores, respectively. Pore sizes can be tuned by changing molecular weights of the BCPs and swelling conditions without the loss of pore uniformity. Due to the nondestructive nature of this swelling process, nothing in the BCPs is lost during the pore-forming procedure, and consequently the formed pores can be progressively closed also by selective swelling. Such reversible pore opening/closing can be repeated many times, enabling the application of these materials in drug delivery and intelligent antireflective coatings. The monodispersed pore sizes, straight pore profile, and hydrophilic pore walls particularly favor the application of the porous BCPs in separations as homoporous membranes (HOMEs) exhibiting high selectivity, permeability, and inherent stimulus responsiveness. © 2016 American Chemical Society.

Gao F.,Linkoping University | Gao F.,University of Cambridge | Tress W.,Linkoping University | Wang J.,University of Cambridge | And 2 more authors.
Physical Review Letters | Year: 2015

The charge generation mechanism in organic photovoltaics is a fundamental yet heavily debated issue. All the generated charges recombine at the open-circuit voltage (VOC), so that investigation of recombined charges at VOC provides a unique approach to understanding charge generation. At low temperatures, we observe a decrease of VOC, which is attributed to reduced charge separation. Comparison between benchmark polymer:fullerene and polymer:polymer blends highlights the critical role of charge delocalization in charge separation and emphasizes the importance of entropy in charge generation. © 2015 American Physical Society.

Jin Y.,Changshu Institute of Technology | Bai G.,Nanjing University of Technology
Journal of Convergence Information Technology | Year: 2012

Wireless Multimedia sensor networks (WMSNs) require simple and reliable error control schemes because of the high energy efficiency request of sensor nodes and high quality of services of wireless media streaming. In this paper, we discuss FEC schemes using energy efficiency analysis on different communication distances and predicts the frame loss rate using the model of GM (1, 1), as well as adjusts the FEC parameter N according to the energy efficiency of the sensor nodes. We proposed a high energy efficiency adaptive cooperative error control mechanism (GM-CFEC). Our mathematical analysis shows that the GM-CFEC mechanism achieves better performance of data transmission comparing with traditional FEC, in terms of the overall energy efficiency of the communications in a WMSN.

Chen S.,Nanjing University of Posts and Telecommunications | Wu Q.,Nanjing University of Posts and Telecommunications | Kong M.,Nanjing University of Posts and Telecommunications | Zhao X.,Nanjing University of Posts and Telecommunications | And 4 more authors.
Journal of Materials Chemistry C | Year: 2013

White organic light-emitting diodes (WOLEDs) have attracted more and more attention in recent years because of their potential applications on flat-panel displays, solid-state lighting, and liquid-crystal display backlighting sources. With the goal towards practical applications, it requires WOLEDs possess not only high brightness and large electroluminescent (EL) efficiency, but also excellent stability. Here, good device stability includes two aspects, these are long operation lifetime and good color stability over a wide EL range. In this review, we explored all possible factors rendering a shift in color in both single- and multiple-emitting layer WOLEDs and summarized some typical design strategies for preventing shift in color of white emission. We hope the present paper can provide valuable clues to academic researchers and industrial designers in developing highly efficient WOLEDs with extremely stable chromaticity. © 2013 The Royal Society of Chemistry.

Zhang X.,Nanjing Southeast University | Zhang X.,University of Alabama | Bao N.,Nanjing University of Technology | Lin B.,Nanjing Southeast University | Gupta A.,University of Alabama
Nanotechnology | Year: 2013

Monodisperse nanocrystals of a new wurtzite phase of Cu 2CoSnS4 (CCTS) have been synthesized using a simple solution-based method. The wurtzite CCTS nanocrystals grow in the shape of nanorods with an average length of 32 ± 2.0 and width of 16 ± 1.5 nm. The more stable stannite phase of CCTS has also been synthesized by increasing the reaction temperature or by a post-high-temperature annealing process. The band gap of wurtzite CCTS nanocrystals is determined to be 1.58 eV. Thin films prepared from the nanocrystal suspension display photoresponse behaviour with white light from a solar simulator, suggesting the potential use of CCTS as an active layer in low-cost thin-film solar cells. © 2013 IOP Publishing Ltd.

Wang H.,Nanjing University of Technology
Journal of Mechanical Science and Technology | Year: 2012

In order to safely grasp an unknown object and accurately perceive its position in the fingers, a finger-tip force sensor which can detect the force and position simultaneously was developed for the underwater dexterous hand. This paper introduced the finger-tip force sensor model which was built by a cylinder elastic body. The principle of force measuring was analyzed theoretically, which proved the reasonableness of the structure and the equation was inferred for measuring force. Because of nonlinear and coupling, a feedforward artificial neural network was employed to calibrate the sensor utilizing the data which were obtained from the tests. The characteristic tests of the sensor showed the maximum error was below 6% in force measurements and the maximum position error was Φ1.6 mm. Then, the application experiments were carried out and the results showed the finger system can track the expectation of force trajectory, which indicated measurement accuracy of the sensor met the demands of research on the underwater dexterous hand. What's more, the sensor structure can compensate the effect of water pressure. So the sensor can be integrated into the finger of the underwater manipulator and used under the water. © 2012 The Korean Society of Mechanical Engineers and Springer-Verlag Berlin Heidelberg.

Liu H.,Nanjing University of Technology | Xue R.,Nanjing Yiyou Controls Instrument Co.
Chung-kuo Tsao Chih/China Pulp and Paper | Year: 2013

The measure of rapidly penetration in cotton linter can greatly reduce and eliminate the defect of the cotton pulp. The detail of the method was introduced in this paper.

Wang Y.,National University of Singapore | Liew J.Y.R.,National University of Singapore | Liew J.Y.R.,Nanjing University of Technology | Lee S.C.,National University of Singapore
International Journal of Impact Engineering | Year: 2015

The structural performance of water tank under static and dynamic pressure loading was experimentally investigated in this paper. The loading was applied using hydraulic actuator/dropped projectile on an inflated high pressure airbag to assert static/dynamic pressure on the specimens. The failure modes and maximum resistance of the specimens were obtained from the test and compared to the numerical results. It was found from the static pressure test that the water tank filled with water exhibited up to 31% increase in flexural resistance under static loading as compared to the empty water tank with the same material and geometry. The improvement was attributed to the effects of water in maintaining the section modulus and delaying the local buckling of the tank. Water was also found to be useful in reducing the deformation of the tank under dynamic pressure loading. Nonlinear finite element analysis was conducted to investigate the behavior of water tank subject to static and dynamic pressure loading and the accuracy of the numerical models was verified by comparing the predicted displacement responses with those observed from the tests. © 2015 Elsevier Ltd. All rights reserved.

Rani S.,Pennsylvania State University | Bao N.,Nanjing University of Technology | Roy S.C.,Pennsylvania State University
Applied Surface Science | Year: 2014

A viable option for recycling carbon dioxide is through the sunlight-powered photocatalytic conversion of CO2 and water vapor into hydrocarbon fuels over highly active nanocatalysts. With photocatalytic CO2 reduction sunlight, a renewable energy source as durable as the sun, is used to drive the catalytic reaction with the resultant fuel products compatible with the current hydrocarbon-based energy infrastructure. The use of co-catalyst (Cu, Pt)-sensitized TiO2 nanoparticle wafers in the photocatalytic conversion of CO2 and water vapor to hydrocarbon fuels, with optimal humidity levels and exposure times established. We also attempted to increase product formation by sputtering both co-catalysts on the nanoparticle wafer's surface, with the resulting product rates significantly higher than that of either the Cu or Pt coated samples. When the TiO2 nanoparticle wafers are used in a flow-through membrane implementation we find a significant increase in product rates of formation, including methane, hydrogen, and carbon monoxide. We believe that nanocatalyst-based flow-through membranes are a viable route for achieving large-scale and low cost photocatalytic solar fuel production. © 2013 Elsevier B.V.

Ren R.,Nanjing University of Technology | Ren R.,Qingdao University of Science and Technology | Leng C.,Qingdao University of Science and Technology | Zhang S.,Qingdao University of Science and Technology
Biosensors and Bioelectronics | Year: 2010

A chronocoulometric DNA sensor was constructed based on doped screen-printed electrode (SPE). Polyaniline nanotubes (PANINTs) and ionic liquid (IL) [C12mim][PF6] were doped into the commercial graphite ink (Electrodag 423SS) for the printing of the SPE, and chitosan was covered on the electrode surface. A homogeneous, stable and highly conductive electrode surface was thus obtained. A chronocoulometric DNA sensor was established based on this SPE. The target DNA sequences were specifically recognized by the capture probes immobilized on the SPE surface and the reporter probes labeled on reporter Au nanoparticles, which also carried bio-bar-code DNA sequences. The signals were generated through chronocoulometric interrogation of [Ru(NH3)6]3+ ions that bound to the DNA strands (mainly bio-bar-code DNAs) via electrostatic interactions. The target DNA could be quantitatively detected in the range from 1.0×10-16M to 1.0×10-14M, and a detection limit of 8.0×10-17M was found. Selectivity against three-mismatched DNA was found in this sensor. © 2010 Elsevier B.V.

Niu X.,Hong Kong Polytechnic University | Niu X.,Nanjing University of Technology | Xiao F.,Hong Kong Polytechnic University | Ma Z.,Hong Kong Polytechnic University
International Journal of Refrigeration | Year: 2012

Liquid desiccant and heat pump (LDHP) hybrid air-conditioning system provides a promising independent air dehumidification solution. Capacity matching among the four major heat and mass transfer components, i.e. dehumidifier, regenerator, evaporator and condenser, is essentially important for energy efficiency of the hybrid system. In this paper, the configuration of the hybrid system is firstly studied. Novel matching indices are proposed to evaluate the matching effect. The results show that a LDHP hybrid system with double-condenser, one solution-cooled and one air-cooled, is a feasible configuration for achieving capacity matching. To achieve dynamic capacity matching under real changing operating conditions, the effects of three critical operating variables, including solution flow rate, revolution of the compressor and air flow rate in the air-cooled condenser, on capacity matching and energy performance are studied. Simulation results show that dynamic capacity matching can only be achieved by regulating these three operating variables simultaneously. © 2011 Elsevier Ltd and IIR. All rights reserved.

Wang J.,Tsinghua University | Zhang Y.,Tsinghua University | Chen Y.,Nanjing University of Technology | Lin M.,Chinese Academy of Agricultural Sciences | Lin Z.,Tsinghua University
Biotechnology and Bioengineering | Year: 2012

Lignocellulosic biomass is regarded as the most viable source of feedstock for industrial biorefinery, but the harmful inhibitors generated from the indispensable pretreatments prior to fermentation remain a daunting technical hurdle. Using an exogenous regulator, irrE, from the radiation-resistant Deinococcus radiodurans, we previously showed that a novel global regulator engineering (GRE) approach significantly enhanced tolerances of Escherichia coli to alcohol and acetate stresses. In this work, an irrE library was subjected to selection under various stresses of furfural, a typical hydrolysate inhibitor. Three furfural tolerant irrE mutants including F1-37 and F2-1 were successfully obtained. The cells containing these mutants reached OD600 levels of 4- to 16-fold of that for the pMD18T cells in growth assay under 0.2% (v/v) furfural stress. The cells containing irrE F1-37 and F2-1 also showed considerably reduced intracellular oxygen species (ROS) levels under furfural stress. Moreover, these two irrE mutants were subsequently found to confer significant cross tolerances to two other most common inhibitors, 5-hydroxymethyl-2-furaldehyde (HMF), vanillin, as well as real lignocellulosic hydrolysates. When evaluated in Luria-Bertani (LB) medium supplemented with corn stover cellulosic hydrolysate (prepared with a solid loading of 30%), the cells containing the mutants exhibited lag phases markedly shortened by 24-44h in comparison with the control cells. This work thus presents a promising step forward to resolve the inhibitor problem for E. coli. From the view of synthetic biology, irrE can be considered as an evolvable "part" for various stresses. Furthermore, this GRE approach can be extended to exploit other exogenous global regulators from extremophiles, and the native counterparts in E. coli, for eliciting industrially useful phenotypes. © 2012 Wiley Periodicals, Inc.

Zeng Y.,Yangzhou University | Wang C.,Yangzhou University | Zhang X.,Yangzhou University | Ju S.,Nanjing University of Technology
Chemical Physics | Year: 2014

Car-Parrinello molecular dynamics was performed on Li+ in water, methanol and ethanol. Structural and dynamical properties of Li+ were studied and compared with experimental data. Excellent agreement was obtained with the experimental data for the structure of the first solvation shell. The results show the Li+ has a more stable tetrahedral coordination in water and methanol than that in ethanol. The diffusion of water in its first solvation shell was rather slow. Compared to water and methanol, the ethanol in the first solvation shell diffuses slower. The decay of orientational profiles of the solvent molecules in the solvation shell shows slower relaxation for first and second rank correlations compared to bulk water and methanol. The decay of orientational correlations for solvation shell molecules shows faster relaxation compared to that of bulk ethanol. Spectral of bound solvent molecules are compared to those of the bulk. Reasonable agreement is obtained with experiments. © 2014 Elsevier B.V. All rights reserved.

Zhou J.,Hong Kong Baptist University | Zhou J.,Nanjing Agricultural University | Zhou J.,Nanjing University of Technology | Zheng G.,Hong Kong Baptist University | And 2 more authors.
Bioresource Technology | Year: 2013

This study sought to elucidate the effect and mechanism of Galactomyces sp. Z3 in improving the bioleaching of heavy metals from sludge. Results showed that co-inoculation of Galactomyces sp. Z3 and two Acidithiobacillus strains (Acidithiobacillus ferrooxidans LX5 and Acidithiobacillus thiooxidans TS6) reduced the period required for sludge bioleaching by 4.5days compared to Acidithiobacillus alone. Further, removal efficiencies of Cu, Zn and oxidation rate of Fe2+ and S0 were higher in co-inoculation system than the Acidithiobacillus alone. Galactomyces sp. Z3 consumed the acetate, propionate, iso-butyrate, butyrate, and iso-valerate in sludge from the initial concentrations of 109.50, 28.80, 7.70, 34.30, and 18.40mg/L to 10.20, 0.61, 0.63, 19.40 and 1.30mg/L, respectively, after 12h in the co-inoculation system, significantly lower than the concentrations observed in the Acidithiobacillus alone. Meanwhile, the surfactant properties of the extracellular polymeric substances produced by the Galactomyces accelerated the rate of sulfur oxidization by A. thiooxidans. © 2013 Elsevier Ltd.

Etherington M.K.,University of Cambridge | Wang J.,University of Cambridge | Wang J.,Nanjing University of Technology | Chow P.C.Y.,University of Cambridge | Greenham N.C.,University of Cambridge
Applied Physics Letters | Year: 2014

We report magnetoconductance measurements on polymer:fullerene photovoltaic devices in the regime of high fields and low temperatures, where spin polarization of injected carriers plays an important role. The current either decreases or increases with magnetic field, depending on whether the interfacial charge-transfer state lies above or below the intramolecular triplet state in energy. Rapid transitions from triplet charge-transfer states to lower-lying triplet excitons constitute an important loss mechanism that is responsible for the negative magnetoconductance observed. © 2014 Author(s).

He C.,Nanjing University | Wu Q.,Nanjing University | Wang X.,Nanjing University | Zhang Y.,Nanjing University | And 5 more authors.
ACS Nano | Year: 2011

AlGaN ternary alloys have unique properties suitable for numerous applications due to their tunable direct band gap from 3.4 to 6.2 eV by changing the composition. Herein we report a convenient chemical vapor deposition growth of the quasi-aligned AlxGa1-xN alloy nanocones over the entire composition range. The nanocones were grown on Si substrates in large area by the reactions between GaCl3, AlCl3 vapors, and NH3 gas under moderate temperature around 700 °C. The as-prepared wurtzite AlxGa1-xN nanocones have single-crystalline structure preferentially growing along the c-axis, with homogeneous composition distribution, as revealed by the characterizations of electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, and selected area electron diffraction. The continuous composition tunability is also demonstrated by the progressive evolutions of the band edge emission in cathodoluminescence and the turn-on and threshold fields in field emission measurements. The successful preparation of AlxGa1-xN nanocones provides the new possibility for the further development of advanced nano- and opto-electronic devices. © 2011 American Chemical Society.

Li S.,Nanjing University of Posts and Telecommunications | Huo F.,Nanjing University of Technology
Nanoscale | Year: 2015

Metal-organic frameworks (MOFs) are a class of crystallized porous polymeric materials consisting of metal ions or clusters linked together by organic bridging ligands. Due to their permanent porosity, rich surface chemistry and tuneable pore sizes, MOFs have emerged as one type of important porous solid and have attracted intensive interests in catalysis, gas adsorption, separation and storage over the past two decades. When compared with pure MOFs, the combination of MOFs with functional species or matrix materials not only shows enhanced properties, but also broadens the applications of MOFs in new fields, such as bio-imaging, drug delivery and electrical catalysis, owing to the interactions of the functional species/matrix with the MOF structures. Although the synthesis, chemical modification and potential applications of MOFs have been reviewed previously, there is an increasing awareness on the synthesis and applications of their composites, which have rarely been reviewed. This review aims to fill this gap and discuss the fabrication, properties, and applications of MOF composites. The remaining challenges and future opportunities in this field, in terms of processing techniques, maximizing composite properties, and prospects for applications, have also been indicated. © The Royal Society of Chemistry 2015.

Zhou X.-H.,Nanjing University of Posts and Telecommunications | Li L.,Nanjing University of Posts and Telecommunications | Li H.-H.,Nanjing University of Posts and Telecommunications | Li A.,Nanjing University of Posts and Telecommunications | And 3 more authors.
Dalton Transactions | Year: 2013

A metal-organic framework (MOF) {[Eu2(MFDA)2(HCOO) 2(H2O)6]·H2O}n (1) (H2MFDA = 9,9-dimethylfluorene-2,7-dicarboxylic acid) has been solvothermally synthesized and structurally characterized. 1 possesses the three-dimensional pcu type rod-packing structure with one-dimensional rhombic channels. The framework of 1 can reversibly shrink/swell along the c axis upon partial/full release of the water molecules. Correspondingly, the rhombic channels become narrow/large and 1 transforms to narrow-pore 1a/large-pore 1b. 1, 1a and 1b have almost the same excitation and emission spectra with the strong characteristic red-light-emission of Eu(iii). A high photoluminescence quantum yield of 77% and long luminescence lifetime of around 1.1 ms was observed for 1. The potential of 1b for Fe3+ ions and PA sensing was studied in DMF through the luminescence quenching experiments, which show 1b is a potential turn-off luminescent sensory material for the selective detection of Fe3+ ions and PA with detection limits of around 10-7 M for both of them. The fluorescence quenching mechanism for Fe3+ ions and PA was also investigated. © 2013 The Royal Society of Chemistry.

Qiao Z.,South China University of Technology | Zhou J.,South China University of Technology | Lu X.,Nanjing University of Technology
Fluid Phase Equilibria | Year: 2014

Amine functionalized materials have drawn researcher's increasing attention to carbon dioxide/methane separation. The kinds or modification densities of amine groups have significant impacts on the adsorption and separation efficiency of carbon dioxide/methane system. In this work, grand canonical Monte Carlo (GCMC) simulations were employed to study the adsorption and separation of carbon dioxide/methane 50:50 mixture by five different metal-organic frameworks (MOFs), the unmodified MIL 53(Al) and four amine functionalized (NH2, (NH2)4, NHCO, CH2CONH2) MIL-53(Al) MOFs. It was found that although original MIL 53 had the best adsorption amount, its separation efficiency is not very high. The carbon dioxide/methane separation factor of (NH2)4 amine functionalized MIL-53 is the best in five MOFs. Moreover, the predicted separation performance of NH2 and NHCO functionalized MIL-53 also surpass that of the original one. However, the predicted separation performance of CH2CONH2 modified MIL-53 is not so good, both its carbon dioxide/methane separation factor and adsorption amount are lower than those of the original one. The geometric effect and energetic effect are analyzed to explain the difference of separation efficiency. This work shows that a rational design of functionalized MOF is a feasible way to improve the carbon dioxide/methane separation efficiency and to provide helpful information for future MOF preparation and applications. © 2013 Elsevier B.V.

Liu J.,Nanjing Normal University | Wang F.,Nanjing University of Technology | Xu T.,Nanjing Normal University | Gu Z.,Nanjing Normal University
Catalysis Letters | Year: 2010

Carbon nanotube supported gold catalysts prepared by deposition- precipitation with urea (DP urea) were characterized by various techniques. Its catalytic activity was examined for the oxidation of styrene using t-butylhydroperoxide as oxidant. This system showed good epoxide selectivity. The other factors, such as solvent, reaction time, concentrations of oxidant and catalyst, have also been investigated and reaction conditions are optimized. It is a novel highly active/selective and reusable heterogeneous catalyst for styrene epoxidation. © 2009 Springer Science+Business Media, LLC.

Wang Y.-H.A.,University of Alabama | Zhang X.,University of Alabama | Zhang X.,Nanjing Southeast University | Bao N.,University of Alabama | And 3 more authors.
Journal of the American Chemical Society | Year: 2011

Monodisperse wurtzite CuInxGa1 - xS2 nanocrystals have been synthesized over the entire composition range using a facile solution-based method. Depending on the chemical composition and synthesis conditions, the morphology of the nanocrystals can be controlled in the form of bullet-like, rod-like, and tadpole-like shapes. The band gap of the nanocrystals increases linearly with increasing Ga concentration, with band gap values for the end members being close to those observed in the bulk. Colloidal suspensions of the nanocrystals are attractive for use as inks for low-cost fabrication of thin film solar cells by spin or spray coating. © 2011 American Chemical Society.

Feng H.,South China University of Technology | Zhou J.,South China University of Technology | Lu X.,Nanjing University of Technology | Fichthorn K.A.,Pennsylvania State University
Journal of Chemical Physics | Year: 2010

Molecular dynamics simulations are carried out to study the interfacial profiles of alkali metal fluoride solutions (NaF, KF, RbF, and CsF) at 1 atm and 300 K. For these solutions, we find that the occupancy of the cations in the interfacial region is comparable to or greater than that of the F- anion. Cations that have weaker hydration abilities have higher concentrations at the interface. The order of enhanced concentrations of cations at the interface is Na+ < K+ < Rb+ < Cs+. The partitioning mechanism can be understood in terms of ionic hydration theory, which shows that the interfacial behavior of ions is related to hydration interactions. This work provides new insight into the interfacial structure of electrolyte solutions and enriches the theory of electrolyte interfaces. © 2010 American Institute of Physics.

Tan Y.,Nanjing University of Technology | Tan Y.,Tsinghua University | Meng L.,Tsinghua University | Peng Q.,Tsinghua University | Li Y.,Tsinghua University
Chemical Communications | Year: 2011

A facile, solution-phase route to mass fabrication of one-dimensional single crystalline Mn3O4 nanowires with a unique core/sheath heteronanostructure, controlled aspect ratios, and narrow diameter distribution was reported. The single crystalline Mn3O4 nanowires have considerably large coercivities (HC > 1 T) at low temperatures. © 2011 The Royal Society of Chemistry.

Zhou D.,Nanjing University of Technology | McGee III O.G.,Howard University
Meccanica | Year: 2013

Three-dimensional (3-D) free vibration of an elastic prism with skew cross-section is investigated using an elasticity-based variational Ritz procedure. Specifically, the associated energy functional minimized in the Ritz procedure is formulated using a simple coordinate mapping to transform the solid skew elastic prism into a unit cube computational domain. The displacements of the prism in each direction are approximately expressed in the form of variable separation. As an enhancement to conventional use of algebraic polynomials trial series in related solid body vibration studies in the associated literature, the assumed skew prism displacement, u, v and w in the computational ξ-η-ζ skew coordinate directions, respectively, are approximated by a set of generalized coefficients multiplied by a finite triplicate Chebyshev polynomial series and boundary functions in ξ-η-ζ to ensure the satisfaction of the geometric boundary conditions of the prism. Upon invoking the stationary condition of the Lagrangian energy functional for the skew elastic prism with respect to the assumed generalized coefficients, the usual characteristic frequency equations of natural vibrations of the skew elastic prism are derived. Upper bound convergence of the first eight non-dimensional frequencies accurate to four significant figures is achieved by using up to 10-15 terms of the assumed skew prism displacement functions. First known 3-D vibration characteristics of skew elastic prisms are examined showing the effects of varying prism length ratios (ranging from skew solids to skew slender beams), as well as, varying cross-sectional side ratios and skewness, which collectively can serve as benchmark studies against which vibration modes predicted by classical Euler and shear deformable skew beam theories as well as alternative methodologies used in elastic prism vibrations of mechanical and structural components. © 2012 Springer Science+Business Media Dordrecht.

Li M.,Nanjing Southeast University | Wu Z.,Nanjing Southeast University | Kao H.,Nanjing University of Technology
Solar Energy Materials and Solar Cells | Year: 2011

The choice of fatty acids as shape-stabilized phase change materials (PCMs) will increase the feasibilities of PCMs in practical applications due to the low price of the fatty acids. Compounding different fatty acids for each other is an effective way to obtain a PCM with a suitable phase-transition temperature. In this study, a series of binary fatty acids composed by capric acid, lauric acid, palmitic acid and stearic acid for each other were prepared using the phase diagram thermal dynamics calculation method. Then these binary fatty acids are absorbed in four kinds of diatomites with different specific areas, which act as a supporting material, to prepare shape-stabilized PCMs. The prepared shape-stabilized PCMs are characterized by the Scanning electron microscope (SEM) and the differential scanning calorimetry (DSC) analysis method. The results show that there is an optimum absorption ratio between binary fatty acids and the diatomite. The latent heat of capriclauric acid/diatomite decreases to 57% of that of capriclauric acid, and the phase-transition temperature rises from 16.36 to 16.74 °C when the capriclauric acid is absorbed in the diatomite. The prepared capriclauric acid/diatomite composite PCM has proper melting temperatures and latent heat for thermal energy storage application in buildings. © 2011 Elsevier B.V.

Li W.,Northeast Normal University | Zhang J.,Northeast Normal University | Guo H.,Nanjing University of Technology | Gahungu G.,Northeast Normal University | Gahungu G.,University of Burundi
Journal of Physical Chemistry C | Year: 2011

The grand canonical Monte Carlo (GCMC) method and high-level first-principle calculations are performed to investigate the role of a constrained channel of microporous organic molecular crystal in separating H2 from binary mixtures containing N2, CH4, or CO2. GCMC simulations show that the selectivity of N2, CH4, or CO2 over H2 is in the order of N 2/H2 < CH4/H2 < CO 2/H2, which is consistent with the order of isosteric heats of adsorption. Particularly at low pressure the selectivity is very high because CO2, CH4, or N2 initially occupies the preferential site in the channel with less sites left for H2. In addition, dispersion corrected density functional theory (DFT-D) is introduced to study the interaction energies and structural properties of the conjugated channel and gases. By comparing with the benchmark data of the coupled-cluster calculations with singles, doubles, and perturbative triple excitations [CCSD(T)] estimated at the complete basis set (CBS) limit, the proper functional is selected. The first-principle calculations confirm that the heterogeneous channel can hold CO2, CH4, or N2 much stronger than H2, suggesting the microporous organic molecular crystal is a good candidate for potential hydrogen purification. © 2011 American Chemical Society.

Li M.,Nanjing Southeast University | Wu Z.,Nanjing Southeast University | Kao H.,Nanjing University of Technology | Tan J.,Nanjing Southeast University
Energy Conversion and Management | Year: 2011

Experimental investigation of preparation and thermal performances of paraffin/bentonite composite phase change material (PCM) are conducted. Paraffin/bentonite composite PCM are prepared by a solution intercalation process. Its composition and structure are characterized by X-ray diffraction (XRD) and scanning electronic microscope (SEM) method. The heat storage and release performances are characterized with differential scanning calorimeter instrument (DSC) curve and temperature-time curves. The results show that the layer distance of bentonite has been increased from 1.49175 nm to 1.96235 nm through organic modification. Paraffin can be intercalated into the layers of bentonite and be made into form-stable composite PCM. The latent heat capacity of the composite PCM is 39.84 J/g. The maximum adsorption ratio of the paraffin in the composite PCM is 44.4%. DSC curve shows that the melting and freezing point of the composite PCM is 41.7 °C and 43.4 °C, respectively, which are approximate to that of paraffin. In addition, the heat transfer rate of prepared paraffin/bentonite composite PCM was enhanced by bentonite. The prepared composite PCM can be used in construction energy-saving and medical care. © 2011 Elsevier Ltd. All rights reserved.

Bao N.,Nanjing University of Technology | Gupta A.,University of Alabama
Journal of Materials Research | Year: 2011

Ordered nanoparticle assemblies can exhibit collective properties that are quite different from those displayed by the individual nanoparticles or their bulk counterpart. This paper reviews recent progress on the assembly of superparamagnetic nanoparticles, with emphasis on different strategies for their chemical fabrication with highly ordered nanostructures as well as their novel properties. Prospective applications of superparamagnetic nanoparticles in the fields of photonic crystals, biomedicine, and biology are also discussed. © Materials Research Society 2011.

Yang N.-R.,Nanjing University of Technology
Jianzhu Cailiao Xuebao/Journal of Building Materials | Year: 2011

The slow progress of the activity of β-C 2S at early age is caused by high temperature synthesis. To change its condition of synthesis, for instance, by pretreating the mixture of n(CaO)/n(SiO 2)=2 under hydrothermal condition to obtain hydrate of calcium silicate and then burning the product ar 700-900°C, the very active product β-C 2S can be obtained. Based on the reports regarding the early activity of β-C 2S published at home and abroad since 80's of the last century, the raw material, the temperature and pressure of the hydrothermal synthesis, the burning temperature, the morphology and the degree of crystallization of the product and other conditions were summarized and analysed. It is concluded that the high early hydration activity of β-C 2S is due to its fine particles, high specific surface area which is 810 times greater than that prepared from high temperature. The various polymerization degrees distribution of [SiO 4] 4- tetrahedron in the process of hydrothermal treatment and hydration of C 2S are analysed as well.

Huang Z.,National University of Singapore | Liew J.Y.R.,National University of Singapore | Liew J.Y.R.,Nanjing University of Technology
Thin-Walled Structures | Year: 2016

Steel-concrete-steel (SCS) sandwich wall infilled with ultra-lightweight cement composite has been developed and proposed for applications in offshore and building constructions. A new form of J-hook connector is introduced to connect the external plates to improve the composite action between the steel face plates and cement composite core to form an integrated unit which is capable of resisting extreme loads. This research experimentally investigates the structural behaviour of SCS sandwich composite wall based on a series of combined compression and uniaxial bending tests on short SCS sandwich composite wall with interlocking J-hook connectors. From the tests, it is found that the SCS sandwich wall exhibits good ductility behaviour with a bending failure mode. Nonlinear finite element (FE) model is also developed to simulate the mechanical behaviour of sandwich wall in terms of ultimate strength and load-deflection curves. Analytical studies show that the N-M interaction model based on Eurocode 4 may over-predict the combined resistance of the SCS sandwich walls subjected to eccentric compression. Therefore, a new approach is proposed to evaluate the resistance of sandwich wall. The axial force versus moment capacity interaction diagrams of sandwich wall are calculated. The validation against the test and FE results shows a reasonable and conservative estimation on the combined resistance of SCS sandwich wall. © 2015 Elsevier Ltd. All rights reserved.

Tan J.,Nanjing University of Technology
Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica | Year: 2015

Helicopter main rotor tip vortex will penetrate into the tip path plane of tail rotor under hover and side-slip conditions, which results in marked variation of tail rotor unsteady aerodynamic loads. In order to more accurately simulate the variation of tail rotor unsteady aerodynamic loads due to main rotor/tail rotor interaction, time-varying item induced by rotor tip vortex is added into pressure term of panel method, which is used to reflect the influence of the velocity impulse and time-varying geometry of rotor tip vortex on unsteady pressure of rotor blades. Meanwhile, viscous effect of vortex particles method is modified through vortex mirror technique to ensure that the rotor vorticity near blades is constant. Thus, the model of unsteady aerodynamic interaction of rotor wake and tail rotor blade is established, and coupled into panel/viscous vortex particle hybrid method to found the analytical method of tail rotor unsteady airloads under main rotor/tail rotor interaction. The unsteady aerodynamic load of AH-1G rotor blade is predicted and compared with the experiment and computational fluid dynamics (CFD) results to validate the effectiveness of the present unsteady aerodynamic interaction model. The influence of main rotor on unsteady aerodynamic loads of tail rotor blade under hover, crosswind, 60° starboard sideslip is analyzed base on NASA ROBIN (Rotor Body Interaction) model. It is shown that the influence of main rotor wake on unsteady aerodynamic loads of tail rotor blade is significant. The average of tail rotor thrust is decreased and the unsteady airload is increased markedly under the main rotor/tail rotor interaction in hover. The “vortex ring” of tail rotor in portside crosswind is weakened by the main rotor/tail rotor interaction, and the tail rotor thrust and unsteady airloads are significantly increased. The damage of tail rotor thrust is the most prominent in 60° starboard sideslip, a phenomenon called “rapid recovery” is observed under low speed sideslip condition, and the amplitude of unsteady airloads of tail rotor is markedly increased due to the main rotor/tail rotor interaction. ©, 2015, AAAS Press of Chinese Society of Aeronautics and Astronautics. All right reserved.

Gao H.,Xian University of Technology | Chang Q.,Xian University of Technology | Yang D.,Nanjing University of Technology
Yi Qi Yi Biao Xue Bao/Chinese Journal of Scientific Instrument | Year: 2014

Electrostatic tomography (EST) is a novel technology for the measurement of the flow parameters of gas-solid two-phase flow. Based on particle charging, EST can achieve flow regime identification and velocity profile measurement through detecting the flowing charged particles. Firstly the effect of the sensitivity map on EST was investigated. The results indicate that with the equal-mesh sensitivity map based regularization algorithm, the charge inversion effect in the center region of the EST sensor is poor. Through analyzing the effect of sensitivity map on EST, a novel unequal-mesh based sensitivity map was proposed to solve the problem. The result indicates that the proposed method can reconstruct the charge distribution in the center region well; however the spatial resolution of the reconstructed image is decreased. Through analyzing the function of the sensitivity map in EST image reconstruction algorithm, the BP algorithm is proposed to realize the image reconstruction in the center region. The experiment results show that the unequal-mesh based sensitivity map and BP algorithm both achieve satisfied results.

Xu H.,Heilongjiang University | Xu H.,National University of Singapore | Chen R.,National University of Singapore | Chen R.,Nanjing University of Posts and Telecommunications | And 7 more authors.
Chemical Society Reviews | Year: 2014

The design and characterization of metal-organic complexes for optoelectronic applications is an active area of research. The metal-organic complex offers unique optical and electronic properties arising from the interplay between the inorganic metal and the organic ligand. The ability to modify chemical structure through control over metal-ligand interaction on a molecular level could directly impact the properties of the complex. When deposited in thin film form, this class of materials enable the fabrication of a wide variety of low-cost electronic and optoelectronic devices. These include light emitting diodes, solar cells, photodetectors, field-effect transistors as well as chemical and biological sensors. Here we present an overview of recent development in metal-organic complexes with controlled molecular structures and tunable properties. Advances in extending the control of molecular structures to solid materials for energy conversion and information technology applications will be highlighted. © 2014 the Partner Organisations.

Du Y.,Nanjing University of Technology | Li G.-Q.,Tongji University
Fire Safety Journal | Year: 2012

To evaluate the fire-resistance of large space buildings, smoke temperature distribution in large space fires is one of the required conditions for determining the temperature elevation history in structures. However, full scale fire experiments on large space building in State Key Laboratory of Fire Science in China revealed that the fire temperature distribution in large space fires are different with that in small compartment fires. In order to standardize the hot smoke temperature in localized fire, a number of ventilated fire scenarios are designed with ceiling height ranging 4-20 m high, floor area ranging 500-6000 m 2 and the rate of heat release ranging 2-25 MW. A wide range of result from a series of large space fire scenarios simulated by FDS (Fire Dynamics Simulator), revealed three important facts. Firstly, temperature distributions throughout the large space fire are non-uniform and pole asymmetric from the fire source. Secondly, the key factors i.e. fire growth type, heat release rate, dimension of internal space and fire area have significant influence on the temperature distribution. Thirdly, with the increase of heat release rate, the maximum temperature is higher and with the increase of the floor area or the internal space height, the maximum temperature is lower. The temperature decays from the plume centerline in horizontal plane. Finally, a new parameter equation that represents the non-uniform fire temperature distribution as a function of time and key factors has been developed by parametric analysis method based on results from numerical tests by using FDS. The new parameter equation agrees well with the numerical test and can be used as the temperature boundary conditions for the lumped differential formulation, from which the transient temperature in elements can be derived. In the meantime this equation can be available for global structural analysis exposed to localized fires. © 2012 Elsevier Ltd.

Liu W.,Zhejiang University | Liu W.,Nanjing University of Technology | Cao F.,Zhejiang University | Xia Y.,Zhejiang University | And 2 more authors.
Electrochimica Acta | Year: 2014

Corrosion of magnesium is initiated from film-free region where the pit corrosion is the main corrosion form. The incubation and growth of active spots in film-free region is affected by the concentration of Cl-and the composition of surface film. Application of scanning electrochemical microscopy (SECM) in feedback mode for corrosion study of AM60 and AMCe1 (AM60 with additional Ce) magnesium alloy in different NaCl solutions is presented. SECM mapping mode was also used to monitor the electrochemical processes on AM60 and AMCe1 alloys immersed in NaCl solutions. The results indicate that the electrochemical behavior of magnesium alloy is different depending on chloride ion concentration and its surface film. Enhanced localized corrosion of magnesium alloy with chloride ions concentration shows that higher concentrated chloride ions results in the rapid initiation and quick growth of active spots, facilitates breakdown and high hydration of surface film. Meanwhile, scratch tests were performed on magnesium alloy, known to develop an artificial defect to monitor variation of electrochemical activity. In the proximity of the local defect, the accelerated electrochemistry activity originating from the high-hydration of surface film is observed when chloride ions are concentrated in the environment. Furthermore, the addition of rare earth element Ce is advantage of reducing the tendency of incubation and growth of active spots due to its more complete and protective surface film. © 2014 Elsevier Ltd.

Zhang Z.,University of Southern Queensland | Wang H.,University of Southern Queensland | Yao X.,Nanjing University of Technology | Zhu Y.,University of Southern Queensland
Cement and Concrete Composites | Year: 2012

A kaolin containing 31 wt.% halloysite and a relatively pure kaolin were selected to study the effects of halloysite on the dissolution behavior of precursors and the formation of geopolymers. The Al and Si concentrations in the leached solutions were studied by inductively coupled plasma-optical emission spectrometry (ICP-OES). The reaction process of metakaolin-activator mixtures was monitored by isothermal conduction calorimetry (ICC) while the reaction products were examined by X-ray diffractometry (XRD), scanning electron microscopy (SEM) and mercury intrusion porosity (MIP). Results showed that the halloysite containing kaolin and its metakaolin possessed higher Si and Al dissolution rate than the purer kaolin and its metakaolin. When mixed with sodium silicate activator at 20°C, the presence of halloysite in kaolin led to a higher geopolymerization rate of metakaolin as reflected by the heat evolution rate. The presence of halloysite improved the reactivity of metakaolin but did not change the geopolymerization pathway under 20°C air curing and 80°C steam curing conditions. The products from the two metakaolins had a similar XRD characteristic (i.e. a typically amorphous diffraction). Only a minor difference in the pore distribution and the porosity was found between those products from the two sources of metakaolins. © 2012 Elsevier Ltd. All rights reserved.

Song P.,Nanjing University of Technology
Synlett | Year: 2011

(A) Sulfinimines were used to prepare functionalized amines with high stereoselectivity. Organometallic reagents, such as Grignard reagents 5a and organolithium,5 are added to sulfinimines to get the desired products in high diastereoselectivity. Both aliphatic and aromatic sulfinimines proceeded in very high diastereoselective ratios when rylboronic acid was employed.6 (B) The sulfinimines-mediated symmetric Strecker reaction provided efficiently chiral α-amino acids. 7 Polyhydroxy α-amino acids were derived from polyhydroxy ulfinimines through smooth deprotection of the sulfinyl.8 uaternary α-stereogenic centers of α-amino acids were controlled by uning the solvents.9 The (S,Rs)- product was afforded predominantly in hexane while the contrary (R,Rs)-isomer was the major product in DMF.(C) β-Amino esters or acids were prepared efficiently via addition of the sodium enolate of methyl acetate to sulfinimines in high diastereoselectivity. 10a Lithium enolate effected the better yield.10b The stereoselective Michael-nucleophilic addition domino reaction from sulfinimines was another route towards β-amino esters.11 (D) β-Amino ketones were prepared by addition of prochiral lithium enolates of Weinreb amides to sulfinimines.5,12 Reduction of Nsulfinyl β-amino ketones led to syn- and anti-1,3-amino alcohols.12 (E) The aza-Diels-Alder reactions of sulfinimines as dienophile with Rawal dienes resulted in dihydropyridones with ee values up to 90%.13a When a Lewis acid catalyst was added, both activated and non-activated dienes could be used in this reaction. 13b (F) The pure sulfinimines have been applied in the aza-Baylis-Hillman reaction. The resulting allylic amines reacted with electrophiles led to highly functionalized 3-sulfinyl and 3-sulfonyl 2,5-cisdihydropyrroles.4(G) Addition of suitably protected α-amino acid to pure sulfinimines led to syn- and anti-α,β- diamino esters with high dr and good yields.15 The water content in THF was an important factor determining the selectivity.15b. © Georg Thieme Verlag Stuttgart.

Kong H.,Nanjing Agricultural University | He J.,Nanjing Agricultural University | Gao Y.,Nanjing Agricultural University | Wu H.,Nanjing University of Technology | And 2 more authors.
Journal of Agricultural and Food Chemistry | Year: 2011

Soybean [Glycine max (L.) Merr.] stalk-based biochar was prepared using oxygen-limited pyrolysis. We evaluated phenanthrene (PHE) and Hg(II) sorption, from single and binary component solutions, onto prepared biochar. We found that the prepared biochar efficiently removed PHE and Hg(II) from aqueous solutions. The isotherms for PHE and Hg(II) sorption could be described using linear and Tóth models, respectively, both with high regression coefficients (R 2 > 0.995). When PHE and Hg(II) coexisted in an aqueous solution, we observed direct competitive sorption, each one suppressing another. Our results provide insight into the recycling of agricultural residues, and also a new application for removal of polycyclic aromatic hydrocarbons and heavy metals from contaminated water utilizing biochar from agricultural residue. © 2011 American Chemical Society.

Huang C.-P.,Nanjing University | Huang C.-P.,Nanjing University of Technology | Yin X.-G.,Nanjing University | Wang Q.-J.,Nanjing University | And 2 more authors.
Physical Review Letters | Year: 2010

The optical properties of a plasmonic crystal composed of gold nanorod particles have been studied. Because of the strong coupling between the incident light and vibrations of free electrons, the long-wavelength optical properties such as the dielectric abnormality and polariton excitation etc., which were suggested originally in ionic crystals, can also be present in the plasmonic crystal. The results show that the plasmonic and ionic lattices may share a common physics. © 2010 The American Physical Society.

Yao J.,Monash University | Yao J.,Nanjing University of Technology | Huang Y.,Monash University | Wang H.,Monash University
Journal of Materials Chemistry | Year: 2010

Polymers have attracted considerable attention in the synthesis of zeolites with controllable structures and morphologies (sizes and shapes) because of their three-dimensional networks, abundant functional groups and designed molecular sizes. Polymer networks can function as a space-confinement additive, a mesopore-forming agent, etc., and significantly affect zeolite nucleation and growth processes. This paper highlights the preparation of hollow/core-shell structures, zeolite nanocrystals, zeolite crystals with tunable shapes and mesoporous structure. © 2010 The Royal Society of Chemistry.

Wang X.,Nanyang Technological University | Sun G.,Nanyang Technological University | Routh P.,Nanyang Technological University | Kim D.-H.,Nanyang Technological University | And 2 more authors.
Chemical Society Reviews | Year: 2014

Heteroatom doping can endow graphene with various new or improved electromagnetic, physicochemical, optical, and structural properties. This greatly extends the arsenal of graphene materials and their potential for a spectrum of applications. Considering the latest developments, we comprehensively and critically discuss the syntheses, properties and emerging applications of the growing family of heteroatom-doped graphene materials. The advantages, disadvantages, and preferential doping features of current synthesis approaches are compared, aiming to provide clues for developing new and controllable synthetic routes. We emphasize the distinct properties resulting from various dopants, different doping levels and configurations, and synergistic effects from co-dopants, hoping to assist a better understanding of doped graphene materials. The mechanisms underlying their advantageous uses for energy storage, energy conversion, sensing, and gas storage are highlighted, aiming to stimulate more competent applications. This journal is © the Partner Organisations 2014.

Lin W.-P.,Nanjing University of Posts and Telecommunications | Liu S.-J.,Nanjing University of Posts and Telecommunications | Gong T.,Nanjing University of Posts and Telecommunications | Zhao Q.,Nanjing University of Posts and Telecommunications | And 2 more authors.
Advanced Materials | Year: 2014

Due to the advantages of good scalability, flexibility, low cost, ease of processing, 3D-stacking capability, and large capacity for data storage, polymer-based resistive memories have been a promising alternative or supplementary devices to conventional inorganic semiconductor-based memory technology, and attracted significant scientific interest as a new and promising research field. In this review, we first introduced the general characteristics of the device structures and fabrication, memory effects, switching mechanisms, and effects of electrodes on memory properties associated with polymer-based resistive memory devices. Subsequently, the research progress concerning the use of single polymers or polymer composites as active materials for resistive memory devices has been summarized and discussed. In particular, we consider a rational approach to their design and discuss how to realize the excellent memory devices and understand the memory mechanisms. Finally, the current challenges and several possible future research directions in this field have also been discussed. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hu Y.N.,Nanjing University of Technology
Applied Mechanics and Materials | Year: 2014

According to China's urban characteristics and features of business-living building, the relationship between residential portion and business portion of business-living building is analyzed, focusing on the business, exposition ability, and the harmony between elevation design and surrounding environment, to describe the specific methods of elevation detail design in order to coordinate the relation between residential and business portions. Findings: according to elaborate design, buildings can be more aesthetically harmonious in favor of the development of urban business-living buildings, and this special type of architecture can also get more recognition. © (2014) Trans Tech Publications, Switzerland.

Zhang Y.,National University of Singapore | Huang L.,Nanjing University of Technology | Liu X.,Agency for Science, Technology and Research Singapore
Angewandte Chemie - International Edition | Year: 2016

We report an epitaxial growth technique for scalable production of hybrid sodium rare-earth fluoride (NaLnF4) microcrystals, including NaYF4, NaYbF4, and NaLuF4 material systems. The single crystalline nature of the as-synthesized products makes them strong upconversion emission. The freedom of combining a lanthanide activator (Er3+ or Tm3+) with a sensitizer (Yb3+) at various doping concentrations readily gives access to color multiplexing at the single-particle level. Our kinetic and thermodynamic investigations on the epitaxial growth of core-shell microcrystals using NaLnF4 particle seeds suggest that within a certain size regime it is plausible to exert precise control over shell thickness and growth orientation under hydrothermal conditions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Leng Y.,Jiangnan University | Liu J.,Jiangnan University | Jiang P.,Jiangnan University | Wang J.,Nanjing University of Technology
RSC Advances | Year: 2012

New heteropolyanion-based polymeric hybrids prepared by the anion-exchange of newly task-specific designed ionic copolymers with Keggin heteropolyacids are revealed to be highly efficient, conveniently recoverable, and steadily reusable catalysts for the oxidation of alcohols with H 2O 2. © The Royal Society of Chemistry 2012.

Shen Y.,Nanjing University of Technology
RSC Advances | Year: 2012

According to Tanabe's hypothesis, a binary oxide exhibits only one acidity type or no acidity. Actually most binary oxides simultaneously exhibit Bronsted and Lewis acidities; Tanabe's hypothesis cannot explain this phenomenon. Taking into account the effects of material structure and the micro-concept of acid sites, on the basis of the Tanabe hypothesis, the author proposes a new hypothesis of micro-region acid sites regarding the surface acidity of binary oxides. © The Royal Society of Chemistry 2012.

Lin C.-W.,National Sun Yat - sen University | Lin C.-W.,University of South Carolina | Chien C.-H.,National Sun Yat - sen University | Tan J.,Nanjing University of Technology | And 2 more authors.
Journal of Power Sources | Year: 2011

Polymer electrolyte membrane (PEM) fuel cell stack requires gaskets and seals in each cell to keep the hydrogen and air/oxygen within their respective regions. The stability of the gaskets/seals is critical to the operating life as well as the electrochemical performance of the fuel cell. Chemical degradation of five elastomeric gasket materials in a simulated and an aggressive accelerated fuel cell solution at PEM operating temperature for up to 63 weeks was investigated in this work. The five materials are copolymeric resin (CR), liquid silicone rubber (LSR), fluorosilicone rubber (FSR), ethylene propylene diene monomer rubber (EPDM), and fluoroelastomer copolymer (FKM). Using optical microscopy, topographical changes on the sample surface due to the acidic environment were revealed. Weight loss of the test samples was monitored. Atomic absorption spectrometer analysis was performed to study the silicon, calcium, and magnesium leachants from the materials into the soaking solution. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy was employed to study the surface chemistry of the materials before and after exposure to the simulated fuel cell environment over time. Among the five materials studied, CR and LSR in the accelerated solution are not as stable as the other three materials. FSR appears to be the most stable. © 2010 Elsevier B.V.

Huang C.-P.,Nanjing University of Technology
Optics Express | Year: 2015

Coupled metasurfaces may refer to a composite plasmonic structure, which consists of multilayered but usually different metasurfaces. A pair of orthogonal plasmonic polarizers, which represents one of such systems, can induce a transmission of light and 90-degree polarization rotation. We explored the effect systematically and found that such effect may be highly efficient and broadband in the near-infrared region. By combining the low-loss metal (silver), the longer operating wavelength, and a work style using propagating waveguide mode, conversion efficiency more than 80% has been suggested near the telecom wavelength. We also suggested that, by overlapping the internal surface-plasmon (2, 0) and (1, 1) modes, an efficient and wideband polarization rotation can be realized. The maximal efficiency is 83% around the wavelength 1340 nm, and the working bandwidth reaches 300 nm. Similar effect has also been revealed in the THz band. The results are useful for constructing compact and highperformance polarization rotators. © 2015 Optical Society of America.

Zhang Q.,Nanjing University of Posts and Telecommunications | Zhang Y.,Nanjing University of Posts and Telecommunications | Xu W.,Nanjing University of Posts and Telecommunications | Li X.,Nanjing University of Posts and Telecommunications | And 4 more authors.
Optics Express | Year: 2015

A series of monodisperse starburst molecules as optical gain media have been investigated in detail. The starburst molecules were composed of a pyrene core with four short oligofluorene arms capped by cyanophenyl moieties. The compounds exhibited low amplified spontaneous emission (ASE) thresholds of 30 nJ pulse-1 and high maximum net gain coefficient of 55 cm-1 under optically pump. Our study demonstrates that the introducing of electron-withdrawing cyanophenyl end-capper onto pyrene centered starburst molecules does not disadvantage their optical gain properties while leading to reduced LUMO level, therefore, improved electron affinity. This study suggested a promising approach for organic gain material synthesis to address the challenge of electrically pumped organic laser. © 2015 Optical Society of America.

Zhao J.H.,Nanjing University of Technology
Applied Mechanics and Materials | Year: 2014

UV/TiO2 photocatalytic of filtrated water are conducted in S waterworks which take Yangtze River as its source water in Nanjing. Self-made glass supported nano-TiO2 film and photocatalytic reactor are used for the experiment. Results show that TOC removal efficiency can reached 45% -63% within 2h-3h, Organic matter removal efficiency is positively related with the • OH generated in photocatalytic process. The influence factors on TOC removal efficiency follows the sequence: light intensity, dissloved oxygen, reaction time and pH. Changes of UV absorption characteristics in photocatalytic process indicate that the saturation of organic matter increase significantly, this is conductive to control the risk taken by disinfection by-products. Results proved that UV/TiO2 photocatalytic is a promising technology for the removal of organic pollutants in drinking water, it can improved the chemical safety of drinking water. © (2014) Trans Tech Publications, Switzerland.

Leng Y.,Jiangnan University | Zhao J.,Jiangnan University | Jiang P.,Jiangnan University | Wang J.,Nanjing University of Technology
ACS Applied Materials and Interfaces | Year: 2014

An amphiphilic composite with magnetic Fe3O4 core and dodecylamine-modified polyoxometalate-paired poly(ionic liquid) shell was synthesized and characterized by 1H NMR, thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, UV-vis spectroscopy, X-ray diffraction (XRD), and digital microscopy. Catalytic tests for H2O2-based epoxidation of bioderived olefins, along with comparisons to various counterparts, demonstrate well that this newly designed catalyst exhibits high activity and selectivity, coupled with convenient magnetic recovery, and effective regeneration. The unique amphiphilic catalyst structure and the intramolecular charge transfer between amino groups and heteropolyanions are revealed to be responsible for the catalyst's excellent performances in epoxidation reactions. © 2014 American Chemical Society.

We describe a method for the determination of inorganic selenium in water samples via gas-phase chemiluminescence (GPCL). Se(IV) was first derivatized with 4-nitro-o-phenylenediamine to form 5-nitropiazselenol. The latter was decomposed by persulfate through photocatalytic oxidation to give Se(VI), which was reduced to Se(IV). Selenium hydride was generated from Se(IV) through reduction with sodium borohydride and then preconcentrated using cryotrapping. The cryotrapped hydride was evaporated and carried to a reaction chamber by a stream of helium, where it produced GPCL as a result of ozonation. The method exhibits a wide linear calibration range (from 0. 5 μg L -1 to 1. 0 mg L -1) with a detection limit of 0. 12 μg L -1 (for n = 11), and a relative standard deviation of 3. 90 % (at n = 11) at 5. 0 μg L -1 level of selenium. The method was applied to the determination of inorganic selenium in water samples and gave satisfactory results. © 2012 Springer-Verlag.

Kong Q.,Nanjing University of Information Science and Technology | Qian H.,Nanjing University of Technology
Fire and Materials | Year: 2014

Mg(OH)2 (MH) nanoparticles were synthesized by hydration of the light-burned MgO at low temperature (70°C). Effects of additives, such as magnesium nitrate and magnesium acetate, on the size, morphology and agglomeration of MH particles were investigated. MH nanoparticles have platelet-like structure and approximately 20-40 nm in thicknesses. The supersaturation degree plays an important role in magnesia hydration and is defined. When magnesium acetate was used as the additive, the hydroxyl ion can be homogeneously introduced into the solution. The size and morphology of MH nanoparticles are more homogeneous. Modified by titanate coupling agent, MH nanoparticles were used as the flame retardant for polypropylene (PP). The combustibility, mechanical properties and thermal behaviors of the PP/MH composites were characterized. The mechanical properties of PP/MH composites are not seriously deteriorated with increasing MH content. When the amount of MH fraction reached 65, the limiting oxygen index (LOI) value and UL 94 testing result of MH65 are 33.8 and V-0 grading, respectively. The onset temperature (T10%) and the maximum thermal decomposition temperature (Tmax) of MH65 separately increased by approximately 100°C and 77°C than those of neat PP. Copyright © 2012 John Wiley & Sons, Ltd.

Huang C.-P.,Nanjing University of Technology | Zhu Y.-Y.,Nanjing University
AIP Advances | Year: 2012

The piezoelectric superlattice (PSL) consisting of periodically inverted ferro- electric domains is a special kind of artificially microstructured material. Similar to the ionic crystals, the strong coupling between the electromagnetic wave and superlattice vibration of PSL may generate the phonon polariton. In this paper, by starting with the piezoelectric equations and classic motion equation, the gap between the artificial and classic lattices has been bridged, where a set of Huang-Kun (HK)-like equations were established and can be shared by both systems. Our results also show that the coupling between the photon and longitudinal "optical" phonon, which is not present in a real crystal, is dominated by the HK-like equations. The connection between the two seemingly different systems suggests that they are governed by a common physics. © 2012 Copyright 2012 Author(s). This article is distributed under a Creative Commons Attribution 3.0 Unported License.

Sun X.,University of Texas-Pan American | Li Q.,University of Texas-Pan American | Lu Y.,Nanjing University of Technology | Mao Y.,University of Texas-Pan American
Chemical Communications | Year: 2013

Three-dimensional (3D) ZnO@MnO2 core@shell branched nanowire arrays exhibit five times higher areal capacitance, better rate performance and smaller inner resistance than their nanowire array counterparts. These novel 3D architectures offer promising designs for powering microelectronics and other autonomous devices on exceptionally small geometric scales. © 2013 The Royal Society of Chemistry.

Li F.,Nanjing University of Technology | Liu X.J.,University of Science and Technology Beijing | Lu Z.P.,University of Science and Technology Beijing
Computational Materials Science | Year: 2014

We have performed molecular dynamics simulations to study the evolution of local atomic structure of the Cu50Zr50 metallic glass during glass formation. It was found that the coordination number of the Cu atoms mainly distribute from 10 to 12, whilst that of the Zr atoms ranges from 13 to 15. The structural analysis showed that the icosahedral-like and Frank-Kasper polyhedra are dominant in both the undercooled liquid and the glass, and Cu5Zr7 and Zr8Cu7 polyhedra are the major local structural units for the Cu- and Zr-centered clusters, respectively. Moreover, three typical medium-range orders constructed by icosahedral-like, Frank-Kasper, and Bernal polyhedra via the linkage of vertex-, edge-, face-, and intercrossed-shared atoms have been revealed in the metallic glass. The peculiar local structures and the connected complex medium-range ordering might be responsible for the high glass forming ability of the binary alloy due to their chemical and structural incompatibility with the primary competing crystalline phase. © 2014 Elsevier B.V. All rights reserved.

Shi C.,Nanjing University of Technology | Shi C.,Qingdao University of Science and Technology | Gu H.,Qingdao University of Science and Technology | Ma C.,Qingdao University of Science and Technology
Analytical Biochemistry | Year: 2010

A novel and sensitive biosensor based on aptamer and pyrene-labeled fluorescent probes for the determination of K + was developed. The aptamer was used as a molecular recognition element and a partially complementary oligonucleotide with the aptamer was labeled by pyrene moieties at both ends to transduce the binding event of K + with aptamer. In the presence of K +, the complementary oligonucleotides were displaced from aptamers, which was accompanied by excimer fluorescence of pyrenes because the self-hairpin structure of the complementary oligonucleotide brought pyrene moieties into close proximity. However, it gave only monomer emission in the absence of K +. Under optimum conditions, the relative fluorescence intensity of pyrene was proportional to the concentration of K + in the range of 6.0 × 10 -4 to 2.0 × 10 -2 M. A detection limit of 4.0 × 10 -4 M was achieved. Moreover, this method was able to detect K + with high selectivity in the presence of Na +, NH 4 +, Mg 2+, and Ca 2+ ions of biological fluids. In brief, the assay may have great potential applications, especially in a biological environment because of its simplicity, sensitivity, and specificity. © 2009 Elsevier Inc. All rights reserved.

Li M.,Nanjing Southeast University | Kao H.,Nanjing University of Technology | Wu Z.,Nanjing Southeast University | Tan J.,Nanjing Southeast University
Applied Energy | Year: 2011

This study prepared a series of binary phase change materials by mixing decanoic acid, dodecanoic acid, hexadecanoic acid. and octadecanoic acid each other. The phase-transition temperature of binary fatty acid and its corresponding mixing proportion are calculated with phase diagram thermodynamic method. The results are verified by the experimental result of the heat absorption curve and the Differential Scanning Calorimetry (DSC) analysis curve. The results show that the calculation method of phase diagram thermodynamic calculation can be taken as a basis for mixing proportion of binary fatty acid phase change materials. In addition, the decanoic-dodecanoic acid/diatomite composite phase change material (PCM) are prepared and its microstructure, thermal property and thermal. reliability. are characterized. The result shows that the decanoic-dodecanoic acid is uniformly adsorbed into diatomite and the form-stable PCM are formed. The phase-transition temperature and the latent heat of the decanoic-dodecanoic acid/diatomite composite PCMs is 16.74. °C and 66.8114 J/g, respectively. © 2010 Elsevier Ltd.

Zhang Y.,Nanjing University of Technology
Physica B: Condensed Matter | Year: 2015

The differential conductance of armchair and zigzag carbon nanotubes (CNTs) in a wide energy range has been numerically calculated by using the tight-binding model and the Green's function method. The effects of the contact coupling between CNTs and electrodes on conductance have been explored. The ballistic conductance is proportional to the band numbers and has a ladder-like feature. As the increase of the contact coupling, the conductance oscillations appear and they are robust against the coupling. More importantly, on the first step of the conductance ladder, the armchair CNTs have two quasi-periodic conductance oscillations, i.e. a rapid conductance oscillation superimposed on a slow fluctuation background; while the zigzag CNTs have only one conductance oscillation. But on the second conductance step, all CNTs have two quasi-periodic conductance oscillations. The physical origin of the conductance oscillations has been revealed. © 2014 Elsevier B.V.

Wang F.,Ewha Womans University | Wang F.,Nanjing University of Technology | Moon J.H.,Sungkyunkwan University | Nandhakumar R.,Ewha Womans University | And 6 more authors.
Chemical Communications | Year: 2013

We have developed a unique binaphthyl-pyrene system 1, whose dihedral angle is reversibly modulated by the addition of Zn2+. Dihedral angle changes in this system were monitored by using circular dichroism (CD) and by an observed "off-on" fluorescence enhancement in aqueous solution. Owing to these changes, the presence of biologically important Zn2+ ions in samples can be readily monitored by employing CD and fluorescence spectroscopy. Finally, the experimental observations made in this effort are supported by the results of quantum mechanical calculations. © 2013 The Royal Society of Chemistry.

Li Y.,Fudan University | Wu Y.,Fudan University | Chang J.,Queensland University of Technology | Chen M.,Fudan University | And 2 more authors.
Chemical Communications | Year: 2013

A new organic dye (FD-9) derived from 1,8-naphthalimide is synthesized and shows significant aggregation induced emission (AIE) characteristics. The FD-9 dye presents excellent photostability and low toxicity, which can specifically track a cell membrane for 4 days. © 2013 The Royal Society of Chemistry.

Shan G.-C.,City University of Hong Kong | Shan G.-C.,Columbia University | Yin Z.-Q.,Tsinghua University | Shek C.H.,City University of Hong Kong | Huang W.,Nanjing University of Technology
Frontiers of Physics | Year: 2014

In this contribution, we briefly recall the basic concepts of quantum optics and properties of semiconductor quantum dot (QD) which are necessary to the understanding of the physics of single-photon generation with single QDs. Firstly, we address the theory of quantum emitter-cavity system, the fluorescence and optical properties of semiconductor QDs, and the photon statistics as well as optical properties of the QDs. We then review the localization of single semiconductor QDs in quantum confined optical microcavity systems to achieve their overall optical properties and performances in terms of strong coupling regime, efficiency, directionality, and polarization control. Furthermore, we will discuss the recent progress on the fabrication of single photon sources, and various approaches for embedding single QDs into microcavities or photonic crystal nanocavities and show how to extend the wavelength range. We focus in particular on new generations of electrically driven QD single photon source leading to high repetition rates, strong coupling regime, and high collection efficiencies at elevated temperature operation. Besides, new developments of room temperature single photon emission in the strong coupling regime are reviewed. The generation of indistinguishable photons and remaining challenges for practical single-photon sources are also discussed. © 2014 Higher Education Press and Springer-Verlag Berlin Heidelberg.

Ma W.,Tsinghua University | Wang X.,Tsinghua University | Zhang J.,Nanjing University of Technology
Journal of Thermal Analysis and Calorimetry | Year: 2011

The nonisothermal crystallization kinetics of poly(vinylidene fluoride) (PVDF) in PVDF/MMT, SiO2, CaCO3, or PTFE composites was investigated through differential scanning calorimetry measurements. The enhanced nucleation of PVDF in its nanocomposites with four types of nanoparticle, and their impact on the crystallization kinetics and melting behaviors were discussed. The modified Avrami method and combined Ozawa-Avrami approaches successfully described the primary crystallization of PVDF in nanocomposite samples under the nonisothermal crystallization process. The activation energy was determined according to the Friedman method and it was quite fit with the results of the analysis according to the modified Avrami model and a combined Ozawa-Avrami model. © 2010 Akadémiai Kiadó, Budapest, Hungary.

Feng J.,Zhejiang Sci-Tech University | Chen J.,Zhejiang Sci-Tech University | Chen J.,Nanjing University of Technology
Journal of Nanoscience and Nanotechnology | Year: 2013

Usually, modifications in normal microRNAs (miRs)-dependent gene expression are induced in transgenic plants expressing viral silencing suppressors or in viruses-inoculated plants. These phenomena are generally interpreted as a side effect of the antiviral silencing suppression. However, it has been recently reported that certain animal miRs prevent viral infection by directly interfering with pathogen replication or by binding to viral transcripts. To investigate whether such mechanisms operate in plants, we performed in silico analysis using tomato miR/miR* sequences and genomes of Cucumber mosaic virus (CMV)-Fny (the severe strain), CMV-Q (the mild strain), the aggravated satellite RNA (satRNA) variant satT1 and the attenuated variant satYn12. Results showed that a total of 38 and 37 miR/miR* sequences could bind to genomic RNAs of CMV-Fny and CMV-Q, respectively. But only one sequence could bind to satT1 and three to satYn12. Interestingly, we found that these miRs/miR*s exhibited significant complementarity within 2a and 3a Open Reading Frames (ORFs) of CMV. And most of the sequences with potential to bind viral genomes were of miR*s, suggesting novel role of miR*s in host defense response. This finding is noteworthy as plant miR* sequences are presently thought very unstable and are not assigned with any function. Finally, we could predict targets in tomato database for the miR/miR* sequences that are highlighted in our study, most of them are involved in plant metabolism. Overall, these results shed light on the possible novel role of plant miR/miR* in antiviral defense mechanisms. Copyright © 2013 American Scientific Publishers All rights reserved.

Rao F.,Nanjing University of Technology
Nonlinear Dynamics | Year: 2014

In this paper, we investigate the complex dynamics of a ratio-dependent spatially extended food chain model. Through a detailed analytical study of the reaction-diffusion model, we obtain some conditions for global stability. On the basis of bifurcation analysis, we present the evolutionary process of pattern formation near the coexistence equilibrium point (N - P - , Z -) via numerical simulation. And the sequence cold spots → stripe-spots mixtures → stripes → hot stripe-spots mixtures → hot spots → chaotic wave patterns controlled by parameters a1 or c1 in the model are presented. These results indicate that the reaction-diffusion model is an appropriate tool for investigating fundamental mechanism of complex spatiotemporal dynamics. © 2014 Springer Science+Business Media Dordrecht.

Li M.,Nanjing Southeast University | Wu Z.,Nanjing Southeast University | Kao H.,Nanjing University of Technology
Applied Energy | Year: 2011

Fatty acid phase change materials (PCMs) have some advantages such as less corrosivity, no separation of subcooling phase and low price. In this paper, capric acid and palmitic acid are composited according to a certain mass ratio to prepare binary fatty acid. Capric-palmitic acid are absorbed into attapulgite by vacuum method to prepare capric-palmitic acid/attapulgite composite PCMs. Analysis methods such as differential scanning analysis (DSC), scanning electron microscope (SEM), Fourier transform infrared (FT-IR) and specific surface analysis (BET method) are used to test the thermal properties, structure and composition of the prepared composite PCM. The results indicate that the pore structure of the caplic-paltimic acid/attapulgite composite PCM is open-ended tubular capillary, which is beneficial to the adsorption. Capric acid and palmitic acid can be absorbed uniformly into attapulgite and the optimum absorption ratio of capric-palmitic binary fatty acid is 35%. There is no chemical reaction between the capric-palmitic acid and attapulgite. The phase change temperature of the capric-palmitic acid/attapulgite composite PCM is 21.71. °C and the latent heat is 48.2. J/g. © 2011 Elsevier Ltd.

He Z.,South China University of Technology | He Z.,Australian National University | Zhou J.,South China University of Technology | Lu X.,Nanjing University of Technology | Corry B.,Australian National University
Journal of Physical Chemistry C | Year: 2013

It is well recognized that ice-like water can be formed in carbon nanotubes (CNTs). Here, we perform molecular dynamics simulations of the hydration of Na+, K+ and Cl- in armchair CNT(n,n) (n = 6, 7, 8, 9 and 10) at 300 K to elucidate the effect of such water structures on ionic hydration. It is found that the interaction of Na+ and K+ with the water molecules is enhanced in CNT(8,8), but is similar or weaker than in bulk in the other CNTs. In bulk, water molecules orient in specific directions around ions due to the electrostatic interaction between them. Under the confinement of CNTs, the hydrogen bonds formed in the first hydration shell of Na+ and K+ disturb this orientation greatly. An exception is in CNT(8,8), where the dipole orientation is even more favorable for cations than in bulk due to the formation of a unique ice-like water structure that aligns the water molecules in specific directions. In contrast, the coordination number is more important than hydration shell orientation in determining the Cl--water interaction. Additionally, the preference for ions to adopt specific radial positions in the CNTs also affects ionic hydration. © 2013 American Chemical Society.

Yao Y.,Hefei University of Technology | Yao Y.,Nanjing University of Technology | Cai Y.,Hefei University of Technology | Lu F.,Hefei University of Technology | And 3 more authors.
Journal of Hazardous Materials | Year: 2014

Magnetic iron based materials are generally effective for many catalytic reactions and can be magnetically recovered after application, showing advantages than other metal oxides. In the present work, magnetic MnFe2O4 nanoparticle and MnFe2O4-reduced graphene oxide (rGO) hybrid were prepared and used as catalysts to activate peroxymonosulfate (PMS) to oxidatively degrade various organic pollutants in water. From a process of chemical deposition and reduction, MnFe2O4-rGO hybrids were produced with nanosized MnFe2O4 particles (ca. 13.2nm). It was found that MnFe2O4 or MnFe2O4-rGO presented high activity in activating PMS to produce sulfate radicals for degradation of organic dyes (Methyl violet, Methyl orange, Methylene blue, Orange II and Rhodamine B) and could be separated with a magnet without any loss. The reaction kinetics, effect of different ion species CL-HCO3-CH3COO-andNO3- and Cl strength, reaction temperature (25-65°C), catalytic stability, as well as degradation mechanism were comprehensively studied. The lower activation energy on MnFe2O4-rGO (25.7kJ/mol) justify the higher chemical performance than that of MnFe2O4 (31.7kJ/mol), suggesting that graphene plays a significant role in the enhanced degradation of dyes. More importantly, the as-prepared MnFe2O4 and MnFe2O4-rGO hybrid exhibited stable performance to remove the organic pollutants in wastewater with easy recycling and good stability by successive degradation experiments. © 2014 Elsevier B.V.

Ren R.,Nanjing University of Technology | Zou Y.,Qingdao Technological University
Sensors and Actuators, B: Chemical | Year: 2011

In this study, an autonomic DNA-reaction cycle involving two cascading DNA polymerization steps was established and utilized for adenosine detection. The reaction cycle was operated based on a probe that was immobilized on the magnetic beads (MBs) and tagged with PbS nanoparticle (NP). Adenosine, as the target, was recognized by its aptamer segment in the probe to initiate the cycle. Two strand-displacement polymerizations took place successively, and in the second polymerization, adenosine was released into the solution, which was then able to initiate another round of cycle. The cycles were automatically repeated, thus adenosine was repetitively utilized as target, amplifying the signal to a great extent. The PbS NP tags were released with the aptamer segments in the cycle, after being separated from the MBs, they were quantified with anodic stripping voltammetry (ASV). It was found that adenosine could be quantified in the range from 2.0 × 10-11 M to 1.0 × 10-9 M. The detection limit was 3.6 × 10-12 M based on 3σ rule. Good selectivity against the analogous nucleosides was shown for this system. The system was also proven to be capable of detecting adenosine in real human serum samples. © 2011 Elsevier B.V.

Xue Y.-S.,Nanjing University | He Y.,University of Texas at San Antonio | Zhou L.,Nanjing University | Chen F.-J.,Nanjing University | And 4 more authors.
Journal of Materials Chemistry A | Year: 2013

By using the octadentate ligand tetrakis[(3,5-dicarboxyphenoxy)methyl] methane (H8L), a rare (4,8)-scu type microporous coordination polymer, [In2L][NH2(CH3)2] 2·(DMF)4(H2O)16, was synthesized and structurally characterized. The compound possesses an anionic three-dimensional open framework and exhibits permanent porosity with selective gas adsorption of CO2 over CH4. It exhibited strong fluorescence emission upon excitation at RT, and a selective, efficient emission quenching response towards nitroaromatic explosives. This journal is © The Royal Society of Chemistry.

Xu X.,University of Arizona | Zhang S.,University of Arizona | Li P.,University of Arizona | Shen Y.,University of Arizona | Shen Y.,Nanjing University of Technology
Fuel | Year: 2014

The adsorptive desulfurization of Jet-A fuel (with sulfur concentrations above 1000 ppmw) using a novel, low-cost adsorbent, 10NiO-CeO 2/7.5Al2O3-SiO2 was investigated in fixed-bed tests. The desulfurization was designated to operate at room temperature and ambient pressure. The flow rate of fuel, size of adsorbent particles, and dimensions of an adsorbent-packed fixed-bed were optimized to obtain a high sulfur adsorption capacity per unit mass of adsorbent. At a breakthrough sulfur concentration of 10 ppmw a very high sulfur adsorption capacity of 0.633 mg S/g adsorbent was achieved. At a mean sulfur concentration of 30 ppmw in the treated accumulated fuel, the best capacity achieved is 1.98 mg S/g adsorbent. The scaling-up strategies for the fixed-bed reactor and the method for adsorbent regeneration are also investigated. Finally, preliminary tests of adsorbent regeneration showed that the first-time regenerated adsorbent could recover 83% of the sulfur removal capacity compared to a fresh adsorbent, and a second time regeneration could recover 50.4% of that of fresh adsorbent. © 2013 Elsevier Ltd. All rights reserved.

Xu X.,University of Arizona | Zhang S.,University of Arizona | Li P.,University of Arizona | Shen Y.,University of Arizona | Shen Y.,Nanjing University of Technology
Fuel Processing Technology | Year: 2014

This article examines and discusses a promising high performance sulfur adsorbent, NiO-CeO2/Al2O3-SiO2, for the desulfurization of Jet-A fuel at ambient conditions. The authors investigated the effects of the amount of nitric acid added during the preparation of the adsorbent supporter, with pseudo-boehmite (70 wt.% Al 2O3) and diatomite (SiO2) used as support materials in the adsorbent. Desulfurization performance due to percentage difference of catalyst species, as well as regeneration of the adsorbent, was evaluated. It was discovered that the improved adsorbent, with optimized material composition and processing procedures, can approach a sulfur adsorption capacity of 1.4 and 3.22 mg-S/g-ads at breakthrough points of 10 and 50 ppmw, respectively. The treated fuel volumes reached 3.02 and 3.58 ml/g-ads at 10 and 50 ppmw, respectively. The improved adsorbent was also tested for four regeneration times. At a breakpoint of 50 ppmw S in effluent fuel, about 75%, 66%, 59% and 51% sulfur adsorption capabilities were recovered in the regenerated adsorbent from cycle 1 to cycle 4. This impressive desulfurization performance at room temperature, and the use of pseudo-boehmite (70 wt.% Al 2O3) and diatomite (SiO2) other than molecule sieves for the support materials, make this sulfur adsorbent very promising. © 2014 Elsevier B.V.

Chen X.,Ewha Womans University | Chen X.,Nanjing University of Technology | Tian X.,Yonsei University | Shin I.,Yonsei University | Yoon J.,Ewha Womans University
Chemical Society Reviews | Year: 2011

Oxidative and nitrosative stress induced by ROS/RNS play crucial roles in a wide range of physiological processes and are also implicated in various diseases, including cancer and neurodegenerative disorders. Sensitive and selective methods for the detection of ROS/RNS based on fluorescent and luminescent probes are of great use in monitoring the in vivo production of these species and elucidating their biological functions. This critical review highlights recent advances that have been made in the development of fluorescent and luminescent probes employed to monitor various ROS/RNS (132 references). © 2011 The Royal Society of Chemistry.

Li S.,Jiangnan University | Li S.,Nanjing University of Technology | Li W.,Jiangnan University | Xiao Q.-Y.,Jiangnan University | Xia Y.,Jiangnan University
Food Chemistry | Year: 2013

Stevioside is an abundant sweetener extracted from Stevia rebaudiana leaf with a bitter aftertaste. Enzymatic transglycosylation of stevioside is a solution to improve the edulcorant quality of stevioside, but highly derivatised stevioside coming with high conversion of stevioside is undesired. In this experiment, the transglycosylation of stevioside was investigated by using a commercial cyclodextrin glucanotransferase and cornstarch hydrolyzate. With controlled parameters, the product was mainly composed of mono- and di-glucosylated stevioside while the highest stevioside conversion reached 77.11%. Neither kinetic nor thermodynamic factor stimulated the formation of high substituted steviosides. The simultaneous hydrolysis in the reaction might inhibit the yield of highly substituted steviosides. © 2012 Elsevier Ltd. All rights reserved.

Wang L.,Nanjing University of Technology | Su R.K.-L.,University of Hong Kong
Journal of Structural Engineering (United States) | Year: 2014

This paper describes an experimental study of axially loaded, fire-exposed, rectangular RC columns repaired with postcompressed steel plates. Seven RC columns with identical section dimensions and reinforcement details were fabricated and tested. Six of these were exposed to a 4-h fire load according to the ISO 834 standard. After 1 month of cooling, five of the fire-exposed columns were installed with precambered steel plates, which were then postcompressed by a method newly developed by the authors. All columns were tested under axial compression to determine their ultimate load capacity, deformation, and ductility. The effects of steel-plate thickness, initial precamber displacements, and preloading level on the ultimate load capacity of repaired RC columns were investigated. The test results show that up to 72% of the original capacity of the axial load-carrying capacity of fire-exposed columns repaired with postcompressed steel plates can be restored. Furthermore, the repaired specimens show better ductility and postpeak deformability. An analytical model was adopted to predict the ultimate axial load capacity of fire-exposed columns repaired with postcompressed steel plates. The comparison of the theoretical and experimental results reveals that the analytical model can accurately predict the ultimate axial load capacity of the repaired columns. © 2013 American Society of Civil Engineers.

Qian J.,Changzhou University | Sun F.,Changzhou University | Qin L.,Nanjing University of Technology
Materials Letters | Year: 2012

Thermally and chemically stable zeolitic imidazolate framework (ZIF) materials have attracted extensive application in gas adsorption and catalysis. Nano-sized ZIF-67 crystals (228 nm) were for the first time synthesized in aqueous solutions at room temperature. As-synthesized crystals were investigated by X-ray diffraction, field-emission scanning electron microscope, thermal gravimetric analysis, gas adsorption measurement. It was found that ZIF-67 nanocrystals were highly stable up to 350 °C and could be stable in boiling methanol at least for 5 days. Furthermore, the concentration of reagents plays an important role in controlling particle size, and diluting the synthesis solution can increase the particle size of final products. © 2012 Elsevier B.V. All rights reserved.

Liu G.,Nanjing University of Technology | Kreinovich V.,University of Texas at El Paso
Journal of Computer and System Sciences | Year: 2010

Convolution y (t) = ∫ a (t - s) ṡ x (s) d s is one of the main techniques in digital signal processing. A straightforward computation of the convolution y (t) requires O (n2) steps, where n is the number of observations x (t0), ..., x (tn - 1). It is well known that by using the Fast Fourier Transform (FFT) algorithm, we can compute convolution much faster, with computation time O (n ṡ log (n)). In practice, we only know the signal x (t) and the function a (t) with uncertainty. Sometimes, we know them with interval uncertainty, i.e., we know intervals [under(x, {combining low line}) (t), over(x, -) (t)] and [under(a, {combining low line}) (t), over(a, -) (t)] that contain the actual (unknown) functions x (t) and a (t). In such situations, it is desirable, for every t, to compute the range [under(y, {combining low line}) (t), over(y, -) (t)] of possible values of y (t). Of course, it is possible to use straightforward interval computations to compute this range, i.e., replace every computational step in FFT by the corresponding operations of interval arithmetic. However, the resulting enclosure is too wide. In this paper, we show how to provide asymptotically accurate ranges for y (t) in time O (n ṡ log (n)). We also explain how to use these new algorithms to compute the convolution (and the Fourier transform) under fuzzy uncertainty. © 2009 Elsevier Inc. All rights reserved.

Huang W.-X.,Nanjing University | Yin X.-G.,Nanjing University | Huang C.-P.,Nanjing University | Huang C.-P.,Nanjing University of Technology | And 3 more authors.
Applied Physics Letters | Year: 2010

We have fabricated a metamaterial of metal/semiconductor/metal sandwich nanostrips structure comprising a pair of gold strips and a vanadium dioxide (VO2) strip. The optical response of the metamaterial has been studied. The results indicate the nanostructure with VO2 strips can be used as a temperature-controlling optical switch and the mechanism of this switch can be explained by the magnetic resonance. © 2010 American Institute of Physics.

Duan J.,Kyoto University | Duan J.,Nanjing University of Technology | Higuchi M.,Kyoto University | Kitagawa S.,Kyoto University
Inorganic Chemistry | Year: 2015

We propose and validate a simple strategy of vertex connection that can be used for framework design and pore size/type modulation to prepare a mother structure and another 10 highly porous isoreticular frameworks with unprecedented topology. Importantly, the potential accessible pore volumes (57-71%), pore sizes (6.8-11. 2 Å; 17.0-29.0 Å; 12.5-22.8 Å; 11.9-24.5 Å), and the pore shapes of this series of highly porous frameworks were simultaneously and systematically tuned. Interestingly, the pore size of IIa [Zn4O(L2)2(BDC)0.5]{(CH3)2NH2} decreased a little less than that of IIc [Zn4O(L2)2(2,6-NDC)0.5]{(CH3)2NH2}; however, its selectivity of CO2 toward CH4 increased by almost two times. © 2015 American Chemical Society.

Ding W.,Nanjing Institute of Technology | Zhu X.,Nanjing Institute of Technology | Huang X.,Nanjing University of Technology
International Journal of Machine Tools and Manufacture | Year: 2016

The tilting-rotary table becomes a standard accessory for five-axis machine tools. An approach for volumetric errors evaluation taking into account servo and geometric errors of the tilting-rotary table is proposed in this paper. A simple machining model of volumetric circles is used to evaluate volumetric errors due to servo errors of the tilting-rotary table. A kinematic error model is used to predict the volumetric errors resulting from geometric errors associated with the tilting-rotary table. Then effects of the two error sources are added to predict the total volumetric errors. A test part obtained by improving the cone frustum specified in NAS979 is presented to validate this method. Cases studies with cutting experiments are carried out on a commercial five-axis machine tool. The results show that the proposed model is effective to evaluate the effect of servo and geometric errors of the tilting-rotary table on volumetric errors in the five-axis machine tool. © 2016 Elsevier B.V. All rights reserved.

Ji S.,Nanjing University of Technology | Ji S.,Hiroshima University | Ji S.,Nagoya Institute of Technology | Zhang F.,Nagoya Institute of Technology | Jin P.,CAS Shanghai Institute of Ceramics
Solar Energy Materials and Solar Cells | Year: 2011

The most important potential application for VO 2 is smart windows. Producing polymer - VO 2 composite film is a practicable alternative for PVD film for windows retrofitting. Here the main work should be concentrated on preparing functional filler - VO 2. In this paper, high quality single crystal VO 2 nanopowder and the composite film coated with this powder had been prepared by a novel and facile route. A new vanadium precursor - V2O5·n H2O sol was fabricated by the dissolution reaction of V 2O 5 in H 2O 2. Adopting this sol, VO 2 powder with an average size less than 20 nm and narrower size distribution was obtained by pre-reduction and hydrothermal treatment. The as-prepared powder showed excellent optical properties in the composite film. The films reached a sufficiently high luminous transmittance (4560%) and keeping thermochromic effect in infrared area very well - an abrupt transmittance change greater than 50% with the phase transition was observed. Its optical properties are comparable with high quality single layer VO 2 film deposited by PVD method. The as-prepared nanopowder has a phase transition temperature ( τc) about 55.5 °C and it can be tuned down to ambient by slight tungsten doping without deteriorating the thermochromic properties, which made this powder very suitable for practical application. Based on our experiments, the τc reduction efficiency of tungsten was about -21.96 K/at.%w in the doping range from 0 to 2.5 at.%w. © 2011 Elsevier B.V. All rights reserved.

Tian B.,Tianjin University | Yin L.,Nanjing University of Technology | Wang H.,University of Manchester
IEEE Transactions on Industrial Electronics | Year: 2015

The finite-time tracking control for reusable launch vehicle with unmatched disturbance is investigated. An adaptive-multivariable-disturbance-compensation scheme is proposed to provide the estimation for external disturbances where the bounds of the perturbations are not known. Based on the estimation, a continuous multivariable homogeneity second order sliding mode controller is designed to ensure that the attitude tracking is achieved in finite time. A proof of the finite-time convergence of the closed-loop system under the integrated controller and disturbance observer is derived using the Lyapunov technique. The features of the proposed control scheme are that it does not require any information on the bounds of the disturbance and its gradient except for their existence. At the same time, the finite-time convergence, nominal performance recovery, and chattering alleviation are guaranteed. Finally, some simulation tests are provided to demonstrate the effectiveness of the proposed control scheme. © 2015 IEEE.

Zhang H.-J.,Shanghai JiaoTong University | Jiang Q.-Z.,Shanghai JiaoTong University | Sun L.,Nanjing University of Technology | Yuan X.,Shanghai JiaoTong University | Ma Z.-F.,Shanghai JiaoTong University
Electrochimica Acta | Year: 2010

The influence of heat treatment on the improvement of the catalytic activity of CoTETA/C catalysts is investigated. These non-precious metal oxygen reduction catalysts are prepared from carbon-supported cobalt triethylenetetramine (CoTETA/C) and heat treated in the temperature interval from 500 to 1000 °C in Ar atmosphere. Electrochemical characteristics are demonstrated in oxygen-saturated acid electrolyte by rotating disk electrode, cyclic voltammetry, as well as single fuel cell tests. The results show that the effect of heat treatment is important on the catalytic activity of CoTETA/C catalysts for the ORR and a maximum catalytic activity is obtained after heat treatment at 800 °C. The ORR reaction mechanism on the catalysts heat treated at 700, 800 and 900 °C is mainly through a 4e reaction path, while a 2e reaction is dominant on the catalysts heat treated at 500, 600 and 1000 °C. Tafel slopes of the CoTETA/C catalysts are all around -200 mV/dec. X-ray absorption measurements reveal that the CoN4 centers are no longer detected after heat treatment. XRD results clearly confirm the formation of nanometallic α-Co with different sizes aggregated. A possible interpretation of the catalytic active sites is also discussed. © 2009 Elsevier Ltd. All rights reserved.

Qiang S.,Nanjing University of Technology
Wuhan Daxue Xuebao (Xinxi Kexue Ban)/Geomatics and Information Science of Wuhan University | Year: 2014

In order to understand and discover the cognition mechanism of the user's acceptance of privacy-preserving technology, we analyze the main information damaging forms and privacy preserving means. After that we use BDI model (Belief, Desire, Intention) combined with information user behavior model to explore the intrinsic mechanism of user's technology acceptance of privacy preserving means. The achievements of the research will optimize the design of information preserving means and ameliorate the strategy of user information service. ©, 2014, Wuhan University. All right reserved.

Li J.,Nanjing University of Technology | Tu S.,East China University of Science and Technology
Huagong Xuebao/CIESC Journal | Year: 2010

The Brinkman-Forchheime-extended Darcy model was used to analyze the laminar flow over a plate heated with a constant heat flux embedded in a porous medium by considering the local non-equilibrium between the fluid and porous medium. The conservation equations were established and simplified by analyzing the order of magnitude of each term. The formulas of velocity and thermal boundary layer thicknesses, convective heat transfer coefficient and local temperature difference between fluid and porous medium were obtained by using an integration method. It is shown that the velocity boundary layer in the porous medium is obviously different from that of free stream over a plain plate. It develops very quickly at the beginning and reaches a steady thickness gradually. However, the development of the thermal boundary layer and the change of the local convective heat transfer coefficient are more similar to that of a plain plate. The local temperature difference between the porous medium and fluid achieves the maximum at the beginning, and then decreases gradually along the flow direction. © All Rights Reserved.

Shao Z.,Nanjing University of Technology | Zhou W.,University of Queensland | Zhu Z.,University of Queensland
Progress in Materials Science | Year: 2012

Solid-oxide fuel cells (SOFCs) technology has a substantial potential in the application of clean and efficient electric power generation. However, the widespread utilization of SOFCs has not been realized because the cost associated with cell fabrication, materials and maintenance is still too high. To increase its competitiveness, lowering the operation temperature to the intermediate range of around 500-800 °C is one of the main goals in current SOFCs research. A major challenge is the development of cell materials with acceptably low ohmic and polarization losses to maintain sufficiently high electrochemical activity at reduced temperatures. During the past few decades, tremendous progress has been made in the development of cell materials and stack design, which have been recently reviewed. SOFCs are fabricated from ceramic or cermet powders. The performances of SOFCs are also closely related to the ways in which the cell materials are processed. Therefore, the optimization of synthetic processes for such materials is of great importance. The conventional solid-phase reaction method of synthesizing SOFCs materials requires high calcination and sintering temperatures, which worsen their microstructure, consequently, their electrochemical properties. Various wet chemical routes have recently been developed to synthesize submicro- to nano-sized oxide powders. This paper provides a comprehensive review on the advanced synthesis of materials for intermediate-temperature SOFCs and their impact on fuel cell performance. Combustion, co-precipitation, hydrothermal, sol-gel and polymeric-complexing processes are thoroughly reviewed. In addition, the parameters relevant to each synthesis process are compared and discussed. The effect of different processes on the electrochemical performance of the materials is evaluated and optimization of the synthesis processes is discussed and some emerging synthetic techniques are also briefly presented. © 2011 Elsevier Ltd. All rights reserved.

Feng Y.,Monash University | Li X.,North China Electrical Power University | Shao Z.,Nanjing University of Technology | Wang H.,Monash University
Journal of Materials Chemistry A | Year: 2015

In this study, the electrochemical performance of hollow Zn2GeO4 nanoparticles as an anode material for lithium-ion batteries (LIBs) has for the first time been investigated and compared to other morphology-type Zn2GeO4 materials with a solid nanorod structure. The results show that the lithium-storage performance is morphology-dependent and the presence of hollow voids is beneficial to enhance the charge-discharge capacity at different current densities. Specifically, the capacity of hollow Zn2GeO4 nanoparticles is approximately 200 mA h g-1 higher than that of Zn2GeO4 solid nanorods after 60 discharge-charge cycles at a current density of 200 mA h g-1 and such high performance (ca. 1200 mA h g-1) is in the front rank of current anode materials and three times as high as that of commercial graphite-based anodes (372 mA h g-1). Moreover, hollow Zn2GeO4 nanoparticles show better rate capacity and the specific capacity is approximately 300 mA h g-1 higher at a current density of 2000 mA h g-1 in comparison with Zn2GeO4 nanorods. The hollow voids not only lower the charge transfer resistance by facilitating lithium-ion diffusion, but also effectively buffer against local volume changes. Therefore, considering the easy and environmentally friendly synthesis and the high performance (high reversible capacity and good rate capacity), such hollow Zn2GeO4 nanoparticles are a very promising candidate as a high-performance anode material for LIBs. © 2015 The Royal Society of Chemistry.

Zhu H.,University of Missouri | Yao X.,Nanjing University of Technology
Journal of Macromolecular Science, Part A: Pure and Applied Chemistry | Year: 2013

A novel poly(acrylamide-co-2-acrylamido-2-methylpropane sulfonic acid)/kaolin (P(AM-co-AMPS)/kaolin) superabsorbent composite was synthesized by copolymerization reaction of acrylamide (AM), 2-acrylamido-2-methylpropane sulfonic acid (AMPS) and kaolin using ammonium persulfate (APS) as an initiator and N,N-methylenebisacrylamide (NMBA) as a crosslinker in an aqueous solution. Evidence of the reaction between kaolin and P(AM-co-AMPS) copolymer was confirmed by comparing the Fourier transform infrared (FTIR) spectra of kaolin, P(AM-co-AMPS) copolymer and P(AM-co-AMPS)/kaolin superabsorbent composite. The reaction was also confirmed by scanning electron microscopy (SEM). Effects of APS, NMBA and kaolin concentrations, weight ratio of AM/AMPS and reaction temperature on water absorbency were investigated. The superabsorbent composite synthesized under the optimum synthesis conditions exhibits the maximum water absorption of 1678 g/g in distilled water and 141 g/g in 0.9 wt% NaCl solution. Results obtained from this study show that P(AM-co-AMPS)/kaolin superabsorbent composite has good water and salt solution absorbency at a relatively high temperature. The gel strength of the superabsorbent composite is significantly increased by increasing the concentration of kaolin. © 2013 Taylor & Francis Group, LLC.

Huang C.-P.,Nanjing University of Technology | Yin X.-G.,Nanjing University | Kong L.-B.,Beijing University of Chemical Technology | Zhu Y.-Y.,Nanjing University
Journal of Physical Chemistry C | Year: 2010

The plasmon coupling in a nanorod dimer obeys the exponential size dependence according to the universal plasmon ruler equation. However, it was shown recently that such a model does not hold at short nanorod distances (Nano Lett. 2009, 9, 1651). Here we study nanorod coupling in various cases, including a nanorod dimer with asymmetrical lengths and a symmetrical dimer with varying gap width. The asymmetrical nanorod dimer causes two plasmon modes: one is the attractive lower energy mode and the other the repulsive high-energy mode. Using a simple coupled LC-resonator model, the position of dimer resonance has been determined analytically. Moreover, we found that the plasmon coupling of a symmetrical cylindrical (or rectangular) nanorod dimer is governed uniquely by the gap width scaled for the (effective) rod radius rather than for the rod length. A new plasmon ruler equation without using the fitting parameters has been proposed which agrees well with the finite-difference time-domain calculations. The method has also been extended to study plasmonic waveguiding in a linear chain of gold nanorod particles. A field decay length up to 2700 nm with a lateral mode size of about 50 nm (∼λ/28) has been suggested. © 2010 American Chemical Society.

Jung H.S.,Korea University | Chen X.,Ewha Womans University | Chen X.,Nanjing University of Technology | Kim J.S.,Korea University | Yoon J.,Ewha Womans University
Chemical Society Reviews | Year: 2013

In the past few decades, the development of optical probes for thiols has attracted great attention because of the biological importance of the thiol-containing molecules such as cysteine (Cys), homocysteine (Hcy), and glutathione (GSH). This tutorial review focuses on various thiol detection methods based on luminescent or colorimetric spectrophotometry published during the period 2010-2012. The discussion covers a diversity of sensing mechanisms such as Michael addition, cyclization with aldehydes, conjugate addition-cyclization, cleavage of sulfonamide and sulfonate esters, thiol-halogen nucleophilic substitution, disulfide exchange, native chemical ligation (NCL), metal complex-displace coordination, and nanomaterial-related and DNA-based chemosensors. This journal is © 2013 The Royal Society of Chemistry.

Qin J.,Nanjing University | Hu L.,Nanjing University | Li G.-N.,Nanjing University | Wang X.-S.,Nanjing University | And 3 more authors.
Organometallics | Year: 2011

A series of tetrathiafulvalene-annulated phenanthroline ligands, 4′,5′-dimethyldithiotetrathiafulvenyl[4,5-f][1,10]phenanthroline (L1), 4′,5′-ethylenedithiotetrathiafulvenyl[4,5-f][1,10] phenanthroline (L2), and 4′,5′-bis(methyloxycarbonyl) dithiotetrathiafulvenyl[4,5-f][1,10]phenanthroline (L3), have been prepared by a facile and efficient synthetic procedure under mild conditions. Further coordination reactions of these ligands with Re(CO)5Cl afford new rhenium tricarbonyl complexes, Re(CO)3Cl(L) (L = L1, 3a; L = L2, 3b; L = L3, 3c), respectively. X-ray crystal structure determinations on 3a,c reveal that the ligands are nearly planar and they show a unique packing mode in the solid state. The electrochemical and spectroscopic behavior of these compounds (L1-L3, 3a-c) has been studied. The results suggest that the redox-active tetrathiafulvalene- phenanthroline ligands are useful for new metal complexes. © 2011 American Chemical Society.

Wang F.,Nanjing University of Technology | Liu J.-H.,Nanjing Normal University | Li W.-M.,China Academy of Safety Science and Technology
Journal of Molecular Catalysis | Year: 2013

Epoxides being very useful and versatile intermediates for the synthesis of many commodities and fine chemicals, and many problems, such as high energy consumption and environmental pollution, existed in industrial production, which makes studies on styrene epoxidation by environmentally friendly methods is a subject of great interest from both academic and industrial points of view. A series of Au-silica (nanosphere) catalysts were prepared by in situ synthesis; highly dispersed gold nanoparticles (GNPs, 6.4 nm) were obtained, and catalytic tests showed good catalytic activity and epoxidation selectivity. The catalysts were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and other instruments, combining with the investigation on the reactivities of styrene epoxidation, the preparation conditions of Au-silica catalysts were optimized.

Zeng C.,Nanjing University of Technology
Industrial and Engineering Chemistry Research | Year: 2013

Fatty acid methyl ester sulfonate (MES) is an environmentally friendly anionic surfactant. It contains RCH(CO2Me)SO3Na (α-MES) as the active component and RCH(CO2Na)SO3Na (the disodium salt) whose content must be lower than 5%. In this paper, MES was prepared first in a falling film microreactor (FFMR) by sulfonation of hydrogenated palm oil methyl ester (ME) with SO3 diluted with N 2, followed by aging in a tubular reactor and subsequent bleaching and neutralization with NaOH. The influences of the ME flow rate, the channel size, the N2 flow rate, the SO3-to-ME molar ratio, and the sulfonation temperature in the sulfonation step, as well as the influences of the SO3-to-ME molar ratio, the aging residence time, and the aging temperature in the aging step, were all examined. The results indicated that the ME flow rate had no evident influence on the ME conversion and the α-MES concentration both without overflow and with overflow. In the sulfonation step, the disodium salt (disalt) concentration increased with increase in the ME flow rate, the channel size, the SO3-to-ME molar ratio, and the sulfonation temperature or decrease in the N2 flow rate. In the aging step, the ME conversion, the α-MES concentration, and the disalt concentration increased with increase in the SO3-to-ME molar ratio, the aging residence time, and the aging temperature. The results of 1H NMR spectra indicated that RCH(CO2Me)SO3H was mainly formed in the sulfonation step in the microreactor, while it was formed in the aging step when the sulfonation was carried out in the conventional falling film reactor. Accordingly, a sulfonation reaction mechanism in the FFMR different from that in the conventional FFR was proposed. The final products with an α-MES concentration of 86.3% and a disalt concentration of 1.2% were obtained under the conditions of a ME flow rate of 2 mL/min, a channel size of 300 × 100 μm, a SO3-to-ME molar ratio of 1.2, a N2 flow rate of 900 mL/min, a sulfonation temperature of 85 C, an aging temperature of 90 C, and an aging residence time of 19.7 min. © 2013 American Chemical Society.

Tan J.,Nanjing University of Technology | Chao Y.J.,University of South Carolina | Yang M.,Shandong University | Lee W.-K.,Jeonbuk Regional Innovation Agency | Van Zee J.W.,University of South Carolina
International Journal of Hydrogen Energy | Year: 2011

Proton exchange membrane (PEM) fuel cell stack requires gaskets in each cell to keep the reactant gas and liquid within their respective regions. Long-term chemical and mechanical stability and durability of the gaskets are critical to both sealing and the electrochemical performance of the fuel cells. In this paper, the chemical and mechanical degradation of a commercially available elastomeric Silicone material were investigated. A simulated solution at two temperatures, that are close to actual PEM fuel cell environment, was used. Optical microscopy was used to show the topographical changes on the sample surface. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and atomic absorption spectrometer analysis were employed to study the surface chemical degradation of the samples after exposure to the simulated PEM fuel cell environment. Microindentation and dynamic mechanical analysis (DMA) were used to assess the change of mechanical properties of the samples exposed to the environment. The ATR-FTIR results indicate that the surface chemistry of the Silicone material was altered after exposure to the environment over time. In addition, atomic absorption spectrometry detected silicon and Calcium leached from the gasket material into the soaking solution. Microindentation test results show that the sample surface hardening occurred and the elastic modulus increased for the Silicone material exposed to the environment. © 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

Zhang W.,Nanyang Technological University | Lu G.,Soochow University of China | Cui C.,Nanyang Technological University | Liu Y.,Nanyang Technological University | And 6 more authors.
Advanced Materials | Year: 2014

The encapsulation of noble-metal nanoparticles (NPs) in metal-organic frameworks (MOFs) with carboxylic acid ligands, the most extensive branch of the MOF family, gives NP/MOF composites that exhibit excellent shape-selective catalytic performance in olefin hydrogenation, aqueous reaction in the reduction of 4-nitrophenol, and faster molecular diffusion in CO oxidation. The strategy of using functionalized cavities of MOFs as hosts for different metal NPs looks promising for the development of high-performance heterogeneous catalysts. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Zhao X.,Karlsruhe Institute of Technology | Zhao-Karger Z.,Karlsruhe Institute of Technology | Wang D.,Karlsruhe Institute of Technology | Wang D.,Nanjing University of Technology | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2013

A key challenge of chloride ion batteries is to develop cathode materials that are stable in the electrolytes. Metal oxychlorides are presented as such a cathode material. The electrochemical performance and the reaction mechanisms of the BiOCl and FeOCl cathode were investigated. Both cathodes showed reversible reactions, including a major conversion reaction and a minor intercalation process, by chloride ion transfer during cycling. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Carreon M.L.,University of Louisville | Li S.,Nanjing University of Technology | Carreon M.A.,University of Louisville
Chemical Communications | Year: 2012

The synthesis of reproducible and continuous AlPO-18 membranes is demonstrated. The separation performance of these membranes for equimolar CO 2/CH 4 gas mixtures is presented. The AlPO-18 membranes displayed CO 2 permeances as high as ∼6.6 × 10 -8 mol m -2 s Pa with CO 2/CH 4 separation selectivities in the ∼52-60 range at 295 K and 138 kPa. © The Royal Society of Chemistry.

Sun G.,Nanyang Technological University | Liu J.,Nanyang Technological University | Zheng L.,Nanyang Technological University | Huang W.,Nanjing University of Technology | Zhang H.,Nanyang Technological University
Angewandte Chemie - International Edition | Year: 2013

Woven into your memories: Aligned multi-walled carbon nanotube (MWCNT) fibers are coated by a thin layer of graphene oxide (GO). The MWCNT fibers work as the top and bottom electrodes while the GO acts as the active layer. By simply cross-stacking two MWCNT@GO fibers, the memory cell obtained shows a write-once-read-many-times effect (see picture). © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ren J.-G.,City University of Hong Kong | Wang C.,City University of Hong Kong | Wu Q.-H.,Quanzhou Normal University | Liu X.,Nanjing University of Technology | And 3 more authors.
Nanoscale | Year: 2014

Toward the increasing demands of portable energy storage and electric vehicle applications, silicon has been emerging as a promising anode material for lithium-ion batteries (LIBs) owing to its high specific capacity. However, serious pulverization of bulk silicon during cycling limits its cycle life. Herein, we report a novel hierarchical Si nanowire (Si NW)-reduced graphene oxide (rGO) composite fabricated using a solvothermal method followed by a chemical vapor deposition process. In the composite, the uniform-sized [111]-oriented Si NWs are well dispersed on the rGO surface and in between rGO sheets. The flexible rGO enables us to maintain the structural integrity and to provide a continuous conductive network of the electrode, which results in over 100 cycles serving as an anode in half cells at a high lithium storage capacity of 2300 mA h g-1. Due to its [111] growth direction and the large contact area with rGO, the Si NWs in the composite show substantially enhanced reaction kinetics compared with other Si NWs or Si particles. This journal is © The Royal Society of Chemistry.

Gao Z.,Nanjing University of Technology
Biotechnology and Applied Biochemistry | Year: 2016

A novel lichenase from Bacillus licheniformis GZ-2 was purified to homogeneity by two steps ion-exchange chromatography with a specific activity of 8231.3 U/mg. The purified enzyme showed as a single protein band with a molecular mass of 25 kDa. The optimum pH and temperature for the enzyme activity were 6.5 and 60 °C, respectively. The enzyme exhibited strict specificity for β-1,3-1,4-d-glucans. The kinetic parameters Km and Vmax were 5.11 mg/mL and 2097 μmol/Min/mg for lichenan and 7.42 mg/mL and 1440 μmol/Min/mg for barley β-glucan. Compared to most of the reported β-1,3-1,4-glucanases (lichenase), the activity of the purified enzyme for lichenan was much higher than that for barley β-glucan. The main products of β-glucan hydrolyzed by the lichenase were cellubiosyltriose (DP3) and cellutriosyltraose (DP4). The lichenase gene from B. licheniformis GZ-2 was cloned and sequenced. The open reading frame of gene gz-2 contained 642 bp coding for a 214 amino acid mature protein. The gene was cloned into an expression vector pET 28a and expressed in Escherichia coli BL21. The activity in cell lysate supernatant was 137.9 U/mg. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

Zhu Z.-F.,Nanjing University of Technology | Guo Z.-X.,Nanjing Southeast University
Gongcheng Lixue/Engineering Mechanics | Year: 2013

A low cyclic reversed load test was carried out on two new precast concrete (NPC) and one cast-in-situ short-leg shear wall specimens. Compared with the cast-in-situ specimen, the strength, stiffness, ductility and energy dissipation of NPC specimens were grasped. The test result shows many contents. The failure mode of NPC specimen is obviously different from that of the cast-in-situ one. The horizontal joint is the weak part with a concentrated deformation. The upper precast shear wall remains in a good condition and the failure presented as shear failure is concentrated in the lower precast shear wall. The finite element analysis shows that: the increase of the connect reinforcements of NPC specimens can increase the contact area of concrete in a horizontal joint, reduce the shear stress, and effectively improve the mechanical behavior of NPC shear wall and enhance its carrying capacity and deformation capacity.

Shen M.,Nanjing University of Technology
Journal of the Franklin Institute | Year: 2013

This paper studies the Hinfin filtering problem for continuous Markov jump linear systems (MJLSs) with partly accessible Markov modes and transition probabilities. A stochastic variable satisfying the Bernoulli random binary distribution is employed to describe the accessibility of Markov mode to the designed filter. Meanwhile, the transition probabilities are allowed to be known, unknown with known lower and upper bounds and completely unknown. Attention is focused on designing a partially mode-dependent Hinfin filter assuring stochastic stability and a prescribed Hinfin performance level for the resulting filtering error system. With resorting to a matrix transformation technique to separate Lyapunov variables from system matrices, sufficient conditions are established in terms of linear matrix inequalities (LMIs). It is worth mentioning that the proposed method covers the existing results as special cases. Finally, a numerical example is given to show the effectiveness of the proposed method. © 2013 The Franklin Institute.

Zhang K.Y.,Nanjing University of Posts and Telecommunications | Zhang J.,Nanjing University of Posts and Telecommunications | Liu Y.,Nanjing University of Posts and Telecommunications | Liu S.,Nanjing University of Posts and Telecommunications | And 5 more authors.
Chemical Science | Year: 2015

We report a ratiometric phosphorescence sensory system for hypochlorite (ClO-) based on core-shell structured silica nanoparticles. Two phosphorescent iridium(iii) complexes were immobilised in the inner solid core and outer mesoporous layer of the nanoparticles, respectively. The former is insensitive to ClO- and thus serves as an internal standard to increase the accuracy and precision, while the latter exhibits a specific and significant luminogenic response to ClO-, providing high selectivity and sensitivity. Upon exposure to ClO-, the nanoparticles display a sharp luminescence colour change from blue to red. Additionally, intracellular detection of exogenous and endogenous ClO- has been demonstrated via ratiometric imaging and photoluminescence lifetime imaging microscopy. Compared to intensity-based sensing, ratiometric and lifetime-based measurements are independent of the probe concentration and are thus less affected by external influences, especially in intracellular applications. This journal is © The Royal Society of Chemistry.

Huang X.,National University of Singapore | Han S.,National University of Singapore | Huang W.,Nanjing University of Technology | Huang W.,Nanjing University of Posts and Telecommunications | And 2 more authors.
Chemical Society Reviews | Year: 2013

Photovoltaic (PV) technologies for solar energy conversion represent promising routes to green and renewable energy generation. Despite relevant PV technologies being available for more than half a century, the production of solar energy remains costly, largely owing to low power conversion efficiencies of solar cells. The main difficulty in improving the efficiency of PV energy conversion lies in the spectral mismatch between the energy distribution of photons in the incident solar spectrum and the bandgap of a semiconductor material. In recent years, luminescent materials, which are capable of converting a broad spectrum of light into photons of a particular wavelength, have been synthesized and used to minimize the losses in the solar-cell-based energy conversion process. In this review, we will survey recent progress in the development of spectral converters, with a particular emphasis on lanthanide-based upconversion, quantum-cutting and down-shifting materials, for PV applications. In addition, we will also present technical challenges that arise in developing cost-effective high-performance solar cells based on these luminescent materials.

Tao T.,Nanjing University | Qian H.-F.,Nanjing University | Qian H.-F.,Nanjing University of Technology | Zhang K.,Nanjing University | And 2 more authors.
Tetrahedron | Year: 2013

Syntheses, characterizations, optical, electrochemical, and thermal properties of a family of linear oligothiophene-based heterocyclic aromatic fluorescent compounds are described herein. They all have effective π-conjugated systems with D-π-D or A-π-A structures as well as different bromo, thiocyano, formyl, and triphenylamino tails. X-ray single-crystal structure of 2TPA2T methanol semisolvate reveals a trans configuration with different dihedral angles between adjacent aromatic heterocycles. Theoretical and experimental studies have been made to reveal the differences from related compounds with adjustable electronic properties. The influences of introducing different D/A functionalized tails on the band-gap convergence have also been discussed, where the convergence behavior corrected via the thienyl ring coefficient (ncorr) shows better correlation of linear fitting based on the extrapolation of HOMO-LUMO gaps at the B3LYP/6-31G* level. © 2013 Elsevier Ltd. All rights reserved.

A method based on conventional finite element analysis is proposed to simulate nanowire tensile behavior. The surface elasticity in nanowires is converted to equivalent Young's modulus and Poisson's ratio for realizing the finite element analysis. The stress and strain distribution of tensile nanowires from the finite element analysis is presented, as well as the effective Young's modulus and Poisson's ratio. Good agreement has been found between the finite element analysis and the analytical results from other researchers. Moreover, a simple formula for the effective Young's modulus is derived. This study provides a new approach to investigate the effect of surface stress on tensile nanowires. © 2015 Author(s).

Liu J.,Nanyang Technological University | Yin Z.,Nanyang Technological University | Cao X.,Nanyang Technological University | Zhao F.,Nanjing University of Posts and Telecommunications | And 4 more authors.
Advanced Materials | Year: 2013

A flexible, all reduced graphene oxide non-volatile memory device, with lightly reduced GO as an active layer and highly reduced GO as both top and bottom electrodes, is fabricated by a full-solution process and its performance is characterized. It provides a convenient method to construct other all-carbon devices. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fan S.,Nanjing University of Technology
Proceedings - International Conference on Artificial Intelligence and Computational Intelligence, AICI 2010 | Year: 2010

Bandyopadhyay and Pal proposed an improved genetic search strategy, GACD (Genetic Algorithm with Chromosome Differentiation), involving partitioning the chromosomes into two classes, and defining a restricted form of the crossover operator between the two classes. The GACD can be applied to many multi-dimensional pattern recognition problems. However, their GACD suffered from three problems, i.e. "sampling-without-replacement", "mating-withbest- chromosome" and "the-unreachable-result". © 2010 IEEE.

Qiu H.,Nanyang Technological University | Qiu H.,Tohoku University | Dong X.,Nanjing University of Technology | Sana B.,Nanyang Technological University | And 4 more authors.
ACS Applied Materials and Interfaces | Year: 2013

The monolithic three-dimensional (3D) graphene network is used as the support for Pt nanoparticles (NPs) to fabricate an advanced 3D graphene-based electrocatalyst. Distinct from previous strategies, the monodispersed Pt NPs with ultrafine particle size (∼3 nm) are synthesized using ferritin protein nanocages as the template and subsequently self-assembled on the 3D graphene by leveraging on the hydrophobic interaction between the ferritin and the graphene. Following the self-assembly, the ferritins are removed, resulting in a stable Pt NP/3D graphene composite. The composite exhibits much enhanced electrocatalytic activity for methanol oxidation as compared with both Pt NP/chemically reduced graphene oxide (Pt/r-GO) and state-of-the-art Pt/C catalyst. The observed electrocatalytic activity also shows marked improvement over Pt/3D graphene prepared by pulse electrodeposition of Pt. This study demonstrates that protein nanocage templating and assembly are promising strategies for the fabrication of functional composites in catalysis and fuel cell applications. © 2013 American Chemical Society.

Gong Y.,Nanjing University of Technology
WIT Transactions on Information and Communication Technologies | Year: 2014

Information is a critical asset of construction project participants, and it can help managers reduce project time and cost, and improve management performance. Information is becoming more important in project lifecycle than before. But project information is scattered in each phase of the project, construction information will seldom be shared or reused if it could not be retrieved correctly and timely. Information loss, which is barriers to improve construction management performance, is popular in construction project lifecycle. It is urgent for contractors to retrieve and reuse previous project information and experiences efficiently in future projects. Construction information is classified in this paper, and information loss is discussed. In order to accumulate and store construction information and reuse it, a conceptual framework of information retrieve and reuse in construction projects is suggested based on systematically modeling. The project information retrieval and reuse framework consists of five functions: retrieve information, digitize information, validate information, build information central base, share and reuse information. © 2014 WIT Press.

Cedeno E.B.,Nanjing University of Technology
Asia-Pacific Power and Energy Engineering Conference, APPEEC | Year: 2014

Adequate generation reserves are needed to avoid failures in case electricity demand exceeds available online generation capacity. Properly determining generation reserves promotes efficient resource allocation. This paper establishes a model to purchase optimal quantities of firm energy and of various reserve capacities for a dispatch period to cover randomness in demand considering transmission network, contingency constraints and costs to start and stop reserve generators. Demand is modeled using a Doubly-truncated Normal Distribution. A synthetic example consisting of 27 generators selling firm and reserve energy created to replicate the operational conditions for a dispatch period of the Midwest Independent System Operator (MISO) is presented to illustrate the proposed procedure. © 2014 IEEE.

Qian L.,National University of Singapore | Li L.,Nanjing University of Technology | Yao S.Q.,National University of Singapore
Accounts of Chemical Research | Year: 2016

Conspectus Enzymes are essential for life, especially in the development of disease and on drug effects, but as we cannot yet directly observe the inside interactions and only partially observe biochemical outcomes, tools "translating" these processes into readable information are essential for better understanding of enzymes as well as for developing effective tools to fight against diseases. Therefore, sensitive small molecule probes suitable for direct in vivo monitoring of enzyme activities are ultimately desirable. For fulfilling this desire, two-photon small molecule enzymatic probes (TSMEPs) producing amplified fluorescent signals based on enzymatic conversion with better photophysical properties and deeper penetration in intact tissues and whole animals have been developed and demonstrated to be powerful in addressing the issues described above. Nonetheless, currently available TSMEPs only cover a small portion of enzymes despite the distinct advantages of two-photon fluorescence microscopy. In this Account, we would like to share design principles for TSMEPs as potential indicators of certain pathology-related biomarkers together with their applications in disease models to inspire more elegant work to be done in this area. Highlights will be addressed on how to equip two-photon fluorescent probes with features amenable for direct assessment of enzyme activities in complex pathological environments. We give three recent examples from our laboratory and collaborations in which TSMEPs are applied to visualize the distribution and activity of enzymes at cellular and organism levels. The first example shows that we could distinguish endogenous phosphatase activity in different organelles; the second illustrates that TSMEP is suitable for specific and sensitive detection of a potential Parkinson's disease marker (monoamine oxidase B) in a variety of biological systems from cells to patient samples, and the third identifies that TSMEPs can be applied to other enzyme families (proteases). Indeed, TSMEPs have helped to uncover new biological roles and functions of a series of enzymes; therefore, we hope to encourage more TSMEPs to be developed for diverse enzymes. Meanwhile, improvements in the TSMEP properties (such as new two-photon fluorophores with longer excitation and emission wavelengths and strategies allowing high specificity) are also indispensable for producing high-fidelity information inside biological systems. We are enthusiastic however that, with these efforts and wider applications of TSMEPs in both research studies and further clinical diagnoses, comprehensive knowledge of enzyme contributions to various physiologies will be obtained. © 2016 American Chemical Society.

Qi H.,Nanjing University of Technology
Chinese Journal of Chemical Engineering | Year: 2011

This paper reports on a new microporous composite silica membrane prepared via acid-catalyzed polymeric route of sol-gel method with tetraethylorthosilicate (TEOS) and a bridged silsesquioxane [1, 2-bis(triethoxysilyl)ethane, BTESE] as precursors. A stable nano-sized composite silica sol with a mean volume size of ∼5 nm was synthesized. A 150 nm-thick defect-free composite silica membrane was deposited on disk support consisting of macroporous α-Al 2O 3 and mesoporous γ-Al 2O 3 intermediate layer by using dip-coating approach, followed by calcination under pure nitrogen atmosphere. The composite silica membranes exhibit molecular sieve properties for small gases like H 2, CO 2, O 2, N 2, CH 4 and SF 6 with hydrogen permeances in the range of (1-4)×10 -7 mol·m -2·s -1·Pa -1 (measured at 200 °C, 3.0×10 5 Pa). With respect to the membrane calcined at 500 °C, it is found that the permselectivities of H 2 (0.289 nm) with respect to N 2 (0.365 nm), CH 4 (0.384 nm) and SF 6 (0.55 nm) are 22.9, 42 and >1000, respectively, which are all much higher than the corresponding Knudsen values (H 2/N 2 = 3.7, H 2/CH 4 = 2.8, and H 2/SF 6 = 8.5).

Zhang Y.,Nanjing University of Technology | Kong D.,Jiangsu Gaochun Ceramics Co. | Feng X.,Red Cross
Ceramics International | Year: 2012

A new method to enhance the flexural strength of porous β-tricalcium phosphate (β-TCP) scaffolds was developed. This new method provides better control over the microstructures of the scaffolds and enhances the scaffolds' mechanical properties. Using this technique, we were able to produce scaffolds with mechanical and structural properties that cannot be attained by either the polymer sponge or slip-casting methods alone or by simply combining the polymer sponge and slip-casting methods. The prepared scaffolds had an open, uniform, interconnected porous structure with a bimodal pore size of 100.0-300.0 μm. The flexural strength of the bimodal porous β-TCP scaffold sintered at 1200 °C was 56.2 MPa and had porosity of 61.4 vol%. The scaffolds obtained provide good mechanical support while maintaining bioactivity, and hence, these bioscaffolds hold promise for applications in hard-tissue engineering. © 2011 Elsevier Ltd and Techna Group S.r.l.

Yang T.,Nanjing Southeast University | Yang T.,Nanjing FullShare Energy Co | Zhang X.,Nanjing Southeast University | Zhou B.,Nanjing University of Technology | Zheng M.,Harbin Institute of Technology
Energy and Buildings | Year: 2013

For the purpose of reducing energy consumption by summer air conditioning and utilizing renewable resources, this paper presents a new type of soil cool storage system with seasonal natural cold source In the cool storage system, the natural cool energy is stored in soil by ground heat exchanger during the cold season and is extracted for space cooling in the summer. Based on film moisture migration theory, a moisture-heat transfer coupling mathematical model is brought up to describe the charging and discharging processes of freeze-thaw phase change of the soil. Besides, a new method is presented that variable time step size is used to solve nonlinear phase change problems numerically. Moreover, a comparison of the model predictions and experimental data shows that the model has good prediction accuracy. The parametric studies indicate that the soil cool storage system full meets the air conditioning needs and has excellence in economic performance. The research results prove that the feasibility of inter-seasonal cool storage system using shallow soil in severe cold regions. © 2013 Elsevier B.V. All rights reserved.

Gao F.,Nanjing University | Yao M.-X.,Nanjing University of Technology | Li Y.-Y.,Nanjing University | Li Y.-Z.,Nanjing University | And 2 more authors.
Inorganic Chemistry | Year: 2013

A series of seven-coordinate mononuclear lanthanide(III) complexes of the general formula [(TPP)Ln(LOEt)]·0.25H2O and [(Pc)Ln(LOEt)] (Ln3+ = Dy3+, Tb3+, Ho3+, and Gd3+; TPP = 5,10,15,20-tetraphenylporphyrinate; Pc = phthalocyaninate; LOEt - = [(η5-C 5H5)Co(P(=O)(OEt)2)3]-) are synthesized on the basis of the tripodal ligand LOEt - and either porphyrin or phthalocyanine ligands. All of the complexes are characterized by X-ray crystallography and by static and dynamic magnetic measurements. The Dy and Tb complexes show the field-induced slow relaxation of magnetization, and they are interesting seven-coordinate single-lanthanide-based SMMs. The magnetic relaxation properties of these double-decker sandwich complexes are influenced by the local molecular symmetry and are sensitive to subtle distortions of the coordination geometry of the paramagnetic lanthanide ions, such as metal-to-plane distances, plane center distances, and bending angles. © 2013 American Chemical Society.

Leng Y.,Jiangnan University | Zhang W.,Jiangnan University | Wang J.,Nanjing University of Technology | Jiang P.,Jiangnan University
Applied Catalysis A: General | Year: 2012

A heteropolyanion-based cross-linked ionic copolymer was prepared by the anion-exchange of a newly task-specific designed amino-containing ionic copolymer with a Keggin heteropolyacid, and characterized by FT-IR, SEM, TG, XRD, UV-vis, ESR, 1H NMR, and elemental analysis. Its catalytic activity was evaluated in the epoxidation of alkenes with aqueous H 2O2. The resultant heteropolyanion-based ionic copolymer is revealed to be a highly efficient heterogeneous catalyst for epoxidation of alkenes with H2O2, adding the advantages of convenient recovery and steady reuse. © 2012 Elsevier B.V.

Yue J.,Nanjing University of Technology
Soil Dynamics and Earthquake Engineering | Year: 2015

A low-cyclic loading test is conducted on a reinforced concrete (RC) column until its failure with the acoustic emission (AE) technique. It ascertains that AE technique is very effective for assessing the damage of RC columns subjected to earthquake-type loadings. The test results show a strong correlation between the hysteretic strain energy and the AE energy histories. Thus, an empirical formula is proposed to predict the level of damage and the closeness to failure of RC columns on the basis of the AE energy recorded by one piezoelectric sensor located near the critical zone. © 2015 Elsevier Ltd.

He Z.,South China University of Technology | He Z.,Australian National University | Zhou J.,South China University of Technology | Lu X.,Nanjing University of Technology | Corry B.,Australian National University
ACS Nano | Year: 2013

Biological protein channels have many remarkable properties such as gating, high permeability, and selectivity, which have motivated researchers to mimic their functions for practical applications. Herein, using molecular dynamics simulations, we design bioinspired nanopores in graphene sheets that can discriminate between Na+ and K+, two ions with very similar properties. The simulation results show that, under transmembrane voltage bias, a nanopore containing four carbonyl groups to mimic the selectivity filter of the KcsA K+ channel preferentially conducts K+ over Na+. A nanopore functionalized by four negatively charged carboxylate groups to mimic the selectivity filter of the NavAb Na + channel selectively binds Na+ but transports K + over Na+. Surprisingly, the ion selectivity of the smaller diameter pore containing three carboxylate groups can be tuned by changing the magnitude of the applied voltage bias. Under lower voltage bias, it transports ions in a single-file manner and exhibits Na+ selectivity, dictated by the knock-on ion conduction and selective blockage by Na+. Under higher voltage bias, the nanopore is K+- selective, as the blockage by Na+ is destabilized and the stronger affinity for carboxylate groups slows the passage of Na+ compared with K+. The computational design of biomimetic ion-selective nanopores helps to understand the mechanisms of selectivity in biological ion channels and may also lead to a wide range of potential applications such as sensitive ion sensors, nanofiltration membranes for Na+/K+ separation, and voltage-tunable nanofluidic devices. © 2013 American Chemical Society.

Li D.,Nanjing University of Technology
Petroleum Processing and Petrochemicals | Year: 2010

A theoretical and experimental study of the filter cake washing and drying performance during the pressure filtration of purified terephthalic acid (PTA) slurry was conducted. Factors affecting the filter cake washing and drying performance were analyzed theoretically. The influence of operating parameters, such as washing intensity and washing water amount on the washing effect was studied, and a mathematical model of PTA filter cake washing was developed. The influence of filter cake drying parameters, such as time and pressure, on the moisture content of filter cake was analyzed, and an affecting rule was obtained. These results will be helpful for the development of one-step PTA pressure filtration technology, which might replace the existed popular two-step PTA centrifugal separation technology in future.

Yuan Z.-H.,Nanjing University | Lu T.,Nanjing University | Lu T.,Nanjing University of Technology
Applied Intelligence | Year: 2013

We present a novel algorithm for 3D reconstruction in this paper, converting incremental 3D reconstruction to an optimization problem by combining two feature-enhancing geometric priors and one photometric consistency constraint under the Bayesian learning framework. Our method first reconstructs an initial 3D model by selecting uniformly distributed key images using a view sphere. Then once a new image is added, we search its correlated reconstructed patches and incrementally update the result model by optimizing the geometric and photometric energy terms. The experimental results illustrate our method is effective for incremental 3D reconstruction and can be further applied for large-scale datasets or to real-time reconstruction. © 2013 Springer Science+Business Media New York.

Cao Z.,Nanjing University of Technology
Wuhan Daxue Xuebao (Xinxi Kexue Ban)/Geomatics and Information Science of Wuhan University | Year: 2014

Concerning the dissimilarity between original spatial data and progressively transmitted spatial data, this paper proposes a model for measuring the similarity of curve datasets. After curve similarity is measured based on differences of the topological and geometric characteristics, the weighted similarity and the similarity precision for curve datasets are computed. The model uses weighted similarity to assess the overall degree of similarity for curve datasets and uses similarity precision to assess the similarity differences between curves. Finally, the model was used in an experiment and verified for effectiveness.

Hu X.,Nanjing University | Hu X.,University of Florida | Ding Z.,Nanjing University of Technology | Ding Z.,University of Florida | And 3 more authors.
Water Research | Year: 2015

Iron (Fe)-impregnated biochar, prepared through a novel method that directly hydrolyzes iron salt onto hickory biochar, was investigated for its performance as a low-cost arsenic (As) sorbent. Although iron impregnation decreased the specific surface areas of the biochar, the impregnated biochar showed much better sorption of aqueous As (maximum sorption capacity of 2.16mgg-1) than the pristine biochar (no/little As sorption capacity). Scanning electron microscope equipped with an energy dispersive spectrometer and X-ray diffraction analysis indicated the presence of crystalline Fe hydroxide in the impregnated biochar but no crystal forms of arsenic were found in the post-sorption biochar samples. However, large shifts in the binding energy of Fe2p, As3d, O1s and C1s region on the following As sorption indicated a change in chemical speciation from As(V) to As(III) and Fe(II) to Fe(III) and strong As interaction with oxygen-containing function groups of the Fe-impregnated biochar. These findings suggest that the As sorption on the Fe-impregnated biochar is mainly controlled by the chemisorption mechanism. Columns packed with Fe-impregnated biochar showed good As retention, and was regenerated with 0.05molL-1 NaHCO3 solution. These findings indicate that Fe-impregnated biochar can be used as a low-cost filter material to remove arsenic from aqueous solutions. © 2014 Elsevier Ltd.

Ren S.,Karlsruhe Institute of Technology | Zhao X.,Karlsruhe Institute of Technology | Zhao X.,Nanjing University of Technology | Chen R.,Karlsruhe Institute of Technology | And 2 more authors.
Journal of Power Sources | Year: 2014

CoFe2O4 nanoparticles anchored into in-situ formed carbon nanofibres were synthesized by a simple solvent-free and template-free pyrolysis-oxidation process and have been investigated as a promising anode material for Li-ion batteries. Ferrocene and cobaltocene as precursor materials, act as both metal and carbon sources. Carbon contents in the composite can be easily adjusted by varying oxidation conditions. The as-prepared composites show a high and stable capacity. More than 700 mAh g-1 based on the total mass of the as-prepared composite was obtained in the composite with 36% carbon content after long-term cycling of 250 cycles. The superior electrochemical properties are suggested to be benefited from the synergistic effects by combining CoFe2O4 and carbon and also their intimate contact developed in the synthetic process. This work opens a facile and broadly applicable way for fabrication and utilization of metal oxide/mixed metal oxide-carbon composites for Li-ion batteries. © 2014 Elsevier B.V. All rights reserved.

Ding C.,Tsinghua University | Hu K.,Nanjing University of Technology | Lin J.-M.,Tsinghua University
Talanta | Year: 2010

We describe herein the combination of electrochemical immunoassay using nanoporous gold (NPG) electrode with horseradish peroxidase (HRP) labeled secondary antibody-gold nanoparticles (AuNPs) bioconjugates for highly sensitive detection of protein in serum. The electroactive product of o-phenylenediamine (OPD) oxidized with H2O2 catalyzed by HRP was reduced in the Britton-Robinson (BR) buffer and the peak current of which was used to determine the concentration of antigen (Ag) in the analyte. The active surface area of NPG electrode was larger than that of a bare flat one. The presence of AuNPs enhanced the immobilized amount of HRP labeled antibody (Ab), which improved the sensitivity of the immunoassay when used as the secondary antibodies. As a result of these two combined effects, the sensitivity of the immunoassay for the determination of target protein was increased significantly. Using hepatitis B surface antigen (HBsAg) as a model, we demonstrate a dose response in the range of 0.01-1.0 ng/mL with a detection limit of 2.3 pg/mL. Analytical results of several human serum samples obtained using the developing technique are in satisfactory agreement with those given by enzyme-linked immune-absorbent assays (ELISA). In addition, the technique was about 100 times more sensitive in the detection of HBsAg than ELISA. All these demonstrated the feasibility of the present immunoassay method for clinical diagnosis. © 2009 Elsevier B.V. All rights reserved.

Li Z.,Tsinghua University | Zhang Y.,Tsinghua University | Su Y.,Tsinghua University | Ouyang P.,Nanjing University of Technology | And 2 more authors.
Chemical Communications | Year: 2014

We report a simple precipitation method for the construction of spatially co-localized multi-enzyme systems based on inorganic nanocrystal-protein complexes. A spatially controlled multi-enzyme system exhibits enhanced overall catalytic performance, allowing for sensitive detection of glucose in solution. This journal is © the Partner Organisations 2014.

Ji S.,Nanjing University of Technology | Ji S.,Nagoya Institute of Technology | Zhang F.,Nagoya Institute of Technology | Jin P.,CAS Shanghai Institute of Ceramics
Journal of Solid State Chemistry | Year: 2011

Missing VO 2(A) usually occurs during the preparation of VO 2 polymorphs. This leads to an ambiguous understanding of the transformation between VO 2 polymorphs. The calculation of the ground state energies for different VO 2 polymorphs indicated that there is only a small energy gap between VO 2(A) and VO 2(R), which destined that the transformation from VO 2(A) to VO 2(R) should be pressure sensitive. This hypothesis was verified during the synthesizing of VO 2 polymorphs by reducing V 2O 5 with oxalic acid through hydrothermal treatment process. Selective formation of pure phase VO 2(A) or VO 2(R) was achieved by controlling the hydrothermal pressure through varying the filling ratio at 270 °C. It was found that a filling ratio over 0.5 favors the formation of pure VO 2(R) while a reduced filling ratio to 0.4 or lower results in the formation of VO 2(A). Based on our experiments, VO 2(B) nanobelts were always first formed and then it transformed to VO 2(A) by assembling process at increased temperature or extended reaction time. Under further higher pressure, the VO 2(A) transformed spontaneously to VO 2(R) initialized from the volume shrinkage due to the formation of denser VO 2(R). © 2011 Elsevier Inc. All rights reserved.

Zhang H.-M.,Yancheng Teachers University | Lou K.,Yancheng Teachers University | Lou K.,Nanjing University of Technology | Cao J.,Yancheng Teachers University | Wang Y.-Q.,Yancheng Teachers University
Langmuir | Year: 2014

The interaction between a hydrophobic-functionalized PAMAM dendrimer (PAMAM-NH2-C12, 25%, G4) and bovine serum albumin (BSA) has been investigated by circular dichroism (CD), UV-vis, and fluorescence spectroscopic methods and molecular modeling. The analysis of the effects of dendrimer complexation on the stability and conformation of BSA indicated that the binding process of the hydrophobic-functionalized dendrimer with BSA induced the relatively large changes in secondary structure of protein. Thermal denaturation of BSA, when carried out in the presence of dendrimer, also indicated that this hydrophobic-functionalized dendrimer acted as a structure destabilizer for BSA. The hydrophobic, electrostatic, and hydrogen bonding forces played important roles in the complex formation. The putative binding site of PAMAM-NH 2-C12 (25%) dendrimer on BSA was near to domain I and domain II. The effect of hydrophobic modification on the stability and structure of BSA would find useful information on the cytotoxicity of PAMAM dendrimer. © 2014 American Chemical Society.

Uchiyama N.,Toyohashi University of Technology | Ouyang H.,Nanjing University of Technology | Sano S.,Toyohashi University of Technology
Mechatronics | Year: 2013

To suppress two-dimensional load sway caused by the horizontal boom motion of a rotary crane, both horizontal and vertical boom motions are generally used. However, it would be more energy efficient and safer if a control scheme using only horizontal boom motion could be developed, eliminating the need for any boom vertical motion. In addition, if we can suppress load sway without the need to measure it, cost reduction of sensors can be achieved. Furthermore, the use of simple velocity trajectory patterns such as a trapezoidal velocity pattern and an S-curve acceleration/deceleration pattern, which are widely used in industrial automation systems, may provide cost-effective implementation of controllers. This paper presents a simple model of rotary crane dynamics that includes only significant centrifugal and Coriolis force terms. This simple model allows analytical solutions of the differential equations of the model to be derived. Thus, S-curve trajectory that considers residual vibration suppression without sensing it, using only horizontal boom motion, can be generated by solving only algebraic equations numerically. The effectiveness of the proposed method is demonstrated by numerical simulations and experimental results. © 2013 Elsevier Ltd. All rights reserved.

Chen Y.,Nanjing University | Shen Y.,Nanjing University | Sun D.,Nanjing University | Zhang H.,Nanjing University | And 3 more authors.
Chemical Communications | Year: 2011

A dispersible graphene/gold nanoclusters hybrid in aqueous solution was fabricated in situ based on the bilayer graphene template, and its electrogenerated chemiluminescence (ECL) behavior was studied. © 2011 The Royal Society of Chemistry.

Yidong G.,Zhejiang University | Yidong G.,Nanjing University of Technology | Xin C.,Nanjing Institute of Environmental Sciences | Shuai Z.,Zhejiang University | Ancheng L.,Zhejiang University
Science of the Total Environment | Year: 2012

The widely spread rural unsanitary landfills in South China pose an environmental threat to water bodies and soil. Although various processing technologies have been utilized for treatment of landfill leachate, their application to the landfills in rural areas is restricted by the availability of skilled professionals and high operation costs. In this experiment, four MSLs with altered soil mixed block (SMB) and different hydraulic load rate (HLR) were applied in the experiment to investigate the treatment of the landfill leachate without aeration or under low aeration supply. The experiment results showed that the improved MSL could effectively treat the chemical oxygen demand (COD), NH4-N and P. COD and NH4-N removal efficiencies of MSL were 97.4%, 82.4% and 72.0%, 62.0%, respectively under HLRs of 200 and 400L/(m2·d) without aeration; COD and NH4-N removal efficiencies of M800 and M1600 were 62.3%, 53.4% and 45.3%, 35.3% respectively under intermittent aeration. N removal efficiency was low due to a strong nitrification effect, and the nitrogen removal capacity of the MSL was greatly reduced at the end of the experiment. P removal efficiency of MSL was 75.6 to 91.9% under HLR 200 and 400L/(m2·d). The intermittent aeration was helpful to remove the clogging of MSLs, after they were clogged under HLRs of 800 and 1600L/(m2·d). MSL is promising as an appealing nitrifying biofilm reactor. © 2012 Elsevier B.V.

Zhou J.F.,Nanjing University of Technology
Journal of Electronic Packaging, Transactions of the ASME | Year: 2014

A model of mini heat sink with microchannels was developed to obtain homogeneous heat transfer capability. The channels are constructed in the form of eight triangular arrays based on a square substrate. Air is sucked from the periphery to the center of the substrate by a vacuum pump and heat transferred from the bottom surface of substrate can be removed by air flowing through channels. Corresponding to the given heat transfer power and the target temperature of substrate, the relationship among length, width and depth of channel was analytically established. By numerical simulation, local pressure drops at the joint of channels and air duct are first obtained and then the dimensions of each channel in a triangular array can be determined one by one. The investigation reveals that the widths of channels will vary with their depths, lengths and pressure differences between two ends. Since all channels are required for the same cooling power, the homogeneous heat transfer of heat sink can be realized. By assembling a certain number of heat sink units, the area of dissipation of heat sink can be enlarged and contoured to fit close to heating surface. Copyright © 2014 by ASME.

Zhang S.,Nanjing University of Science and Technology | Yang X.,Nanjing University of Technology | Zhong Q.,Nanjing University of Science and Technology
Journal of Fluorine Chemistry | Year: 2013

Cluster molecular modeling of F-doped V2O5-WO 3/TiO2 catalyst was studied using density functional theory and first principles molecular dynamics simulations. The results showed that (i) site location of F above TiO2 (0 0 1) was that F atom instead bridging oxygen of TiO2; (ii) oxygen vacancies could form at the position of bridging oxygen over F-doped TiO2 supporter; (iii) oxygen vacancies by F doping showed higher activity and W species could interact with oxygen vacancies by one trapped electron; (iv) the reduced value of W species could form over WTiF and VWTiF catalyst; (v) V species improved the formation of reduced value of W species. These results facilitated the formation of reduced W species that was important to improve the formation of superoxide ions. © 2013 Elsevier B.V. All rights reserved.

Cao W.,Nanjing University of Technology | Su M.,Qingdao University of Science and Technology | Zhang S.,Qingdao University of Science and Technology
Electrophoresis | Year: 2010

A rapid and sensitive DNA targets detection using enzyme amplified electrochemical detection (ED) based on microchip was described. We employed a biotin-modified DNA, which reacted with avidin-conjugated horseradish peroxidase (avidin-HRP) to obtain the HRP-labeled DNA probe and hybridized with its complementary target. After hybridization, the mixture containing dsDNA-HRP, excess ssDNA-HRP, and remaining avidin-HRP was separated by MCE. The separations were performed at a separation voltage of +1.6 kV and were completed in less than 100 s. The HRP was used as catalytic labels to catalyze H2O 2/o-aminophenol reaction. Target DNA could be detected by the HRP-catalyzed reduction with ED. With this protocol, the limits of quantification for the hybridization assay of 21- and 39-mer DNA fragments were of 8x10-12M and 1.2x10-11 M, respectively. The proposed method has been applied satisfactorily in the analysis of Escherichia coli genomic DNA. We selected the detection of PCR amplifications from the gene of E. coli to test the real applicability of our method. By using an asymmetric PCR protocol, we obtained ssDNA targets of 148 bp that could be directly hybridized by the single-stranded probe and detected with ED. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA.

Shen Y.,Nanjing University of Technology | Shen Y.,University of Arizona | Li P.,University of Arizona | Xu X.,University of Arizona | Liu H.,University of Arizona
RSC Advances | Year: 2012

Jet fuels are strategic fuels widely used in airplanes. Through appropriate reforming and shifting processing, jet fuels can be converted into syngas, which is a suitable fuel to solid oxide fuel cells for many auxiliary and backup power units. Integrated micro fuel processors in combination with solid oxide fuel cell (SOFC) stacks using jet fuels have been viewed as attractive portable power sources. Because the sulfur in jet fuels easily causes catalyst poisoning for fuel processing reactions and the electrochemical reactions in fuel cells, ultra-deep sulfur removal in jet fuels and many other hydrocarbon fuels has become a very important and active research subject worldwide in the last 15 years. Amongst the state-of-the-art technologies, selective adsorption for removing sulfur (SARS) is emerged to be very attractive. SARS has been regarded as the most promising approach because it obtains ultra-deep desulfurization efficiency at ambient temperature and atmospheric pressure without hydrogen consumption. In this paper, we survey the current status and prospect of the SARS technology for jet fuels, and will discuss some important issues remaining for the SARS technology in the future. The final goal of this survey is to find/innovate a promising method for jet fuel desulfurization, which is most suitable for supplying fuels to solid oxide fuel cell auxiliary and backup power units. © 2012 The Royal Society of Chemistry.

Mo L.,University of Toronto | Mo L.,Nanjing University of Technology | Panesar D.K.,University of Toronto
Cement and Concrete Research | Year: 2012

Reactive MgO is produced at a lower kiln temperature compared to ordinary Portland cement (OPC) and gains its physical properties mainly as a result of carbonation processes. Use of reactive MgO as cement replacement has recently gained attention in context with precast concrete products subjected to carbonation curing. This study investigates pastes containing 0-40% reactive MgO and the effect of accelerated carbonation curing on the: formation of new carbonate phases, microstructural development, and microhardness. Outcomes from this study revealed that the primary Ca and Mg-bearing carbonates formed are calcite, aragonite, magnesium calcite, and nesquehonite. The combined effect of carbonation and reactive MgO resulted in: a reduction in pore size and total pore volume, increase in apparent density, and greater microhardness compared to OPC paste. The chemical processes, and physical properties revealed that the dense inter-connected network structure consisting of Ca and Mg carbonates is a significant factor that influences the microhardness. © 2012 Elsevier Ltd. All rights reserved.

Xuan Y.M.,Hong Kong Polytechnic University | Xuan Y.M.,Shanxi University | Xiao F.,Hong Kong Polytechnic University | Niu X.F.,Hong Kong Polytechnic University | And 3 more authors.
Renewable and Sustainable Energy Reviews | Year: 2012

Evaporative cooling is an energy efficient and environmentally friendly air conditioning technology. Research and application of evaporative cooling in China have been very fruitful; however, they were little known to the world because most of works were published in Chinese. Therefore, this paper intends to present a comprehensive summary on them. The working principles and thermodynamic characteristics of different types of evaporative cooling, including direct, indirect and semi-indirect evaporative cooling, are first introduced. Experimental and theoretical research works on feasibility studies, performance test and optimization as well as heat and mass transfer analysis are then reviewed in detail. The feasibilities of evaporative cooling under different climates, efficiencies of various evaporative cooling equipment, and critical parameters and techniques for improving the efficiencies as well as numerical modeling of evaporative cooling processes are recalled. The typical systems and equipments of evaporative cooling adopted in China are reviewed in Part II. © 2012 Elsevier Ltd. All rights reserved.

Barnes E.O.,University of Oxford | Chen X.,University of Oxford | Chen X.,Nanjing University of Technology | Li P.,University of Oxford | Compton R.G.,University of Oxford
Journal of Electroanalytical Chemistry | Year: 2014

Theory is presented to simulate both chronoamperometry and cyclic voltammetry at porous electrodes fabricated by means of electro-deposition around spherical templates. A theoretical method to extract heterogeneous rate constants for quasireversible and irreversible systems is proposed by the approximation of decoupling of the diffusion within the porous electrode and of bulk diffusion to the electrode surface. © 2014 Elsevier B.V. All rights reserved.

Fu J.,National University of Singapore | Yu C.,National University of Singapore | Li L.,National University of Singapore | Li L.,Nanjing University of Technology | Yao S.Q.,National University of Singapore
Journal of the American Chemical Society | Year: 2015

The efficient delivery of bioactive compounds into cells is a major challenge in drug discovery. We report herein the development of novel methods for intracellular delivery of functional proteins (including antibodies) and native small-molecule drugs by making use of cell-penetrating poly(disulfide)s (CPDs). CPDs were recently shown to be rapidly taken up by mammalian cells in endocytosis-independent pathways, but their applications for delivery of proteins and native small-molecule drugs have not been demonstrated. With our newly developed, CPD-assisted approaches, rapid and "bioorthogonal" loading of cargos was carried out with pre-synthesized CPDs, in two steps and in a matter of minutes under aqueous conditions. The resulting CPD-cargo conjugates were used immediately for subsequent cell delivery studies. With the versatility and flexibility of these methods, we further showed that they could be used for immediate delivery of a variety of functional cargos with minimum chemical and genetic manipulations. The minimal cell cytotoxicity of these CPDs and their cargo-loaded conjugates further highlights the unique advantage of this new cell-transduction method over other existing strategies and ensures that our entire delivery protocol is compatible with subsequent live-cell experiments and biological studies. © 2015 American Chemical Society.

Wang Z.-M.,Nanjing Medical University | Zhou B.,Nanjing University of Technology | Wang Y.-S.,Nanjing Medical University | Gong Q.-Y.,Nanjing University of Traditional Chinese Medicine | And 4 more authors.
American Journal of Clinical Nutrition | Year: 2011

Background: Epidemiologic studies are inconsistent regarding the association between tea consumption and the risk of coronary artery disease (CAD). Objective: The objective was to perform a meta-analysis to determine whether an association exists between tea consumption and total CAD endpoints in observational studies. Design: We searched PUBMED and EMBASE databases for studies conducted from 1966 through November 2009. Study-specific risk estimates were combined by using a random-effects model. Results: A total of 18 studies were included in the meta-analysis: 13 studies on black tea and 5 studies on green tea. For black tea, no significant association was found through the meta-analysis [highest compared with lowest, summary relative risk (RR): 0.92; 95% CI: 0.82, 1.04; an increment of 1 cup/d, summary RR: 0.98; 95% CI: 0.94, 1.02]. For green tea, the summary RR indicated a significant association between the highest green tea consumption and reduced risk of CAD (summary RR: 0.72; 95% CI: 0.58, 0.89). Furthermore, an increase in green tea consumption of 1 cup/d was associated with a 10% decrease in the risk of developing CAD (summary RR: 0.90; 95% CI: 0.82, 0.99). Conclusions: Our data do not support a protective role of black tea against CAD. The limited data available on green tea support a tentative association of green tea consumption with a reduced risk of CAD. However, additional studies are needed to make a convincing case for this association. © 2011 American Society for Nutrition.

Zhou J.-F.,Nanjing University of Technology
Gao Xiao Hua Xue Gong Cheng Xue Bao/Journal of Chemical Engineering of Chinese Universities | Year: 2014

A molecular dynamics model of Couette flow was established to investigate the shear flow characteristics of ultra-thin nanofluid film, taking into account the interactions among Cu nanoparticles, Ar atoms and Pt atoms. The temperature-related vibration of Pt atoms in the two parallel solid walls was considered in the model. It is revealed that the vibration of Pt atoms has an obvious influence on the motion of Ar atoms and Cu nanoparticles which distribute unevenly along film thickness direction. Due to the uneven distribution of Ar atoms and the effect of Cu nanoparticles, the tangential velocity of the liquid layers varies nonlinearly along thickness direction. At wall boundary there exists obvious slip velocity influenced by system temperature, and it increases with increasing shearing velocity of the slid walls. The shear viscosity of nanofuild was found to increase with increasing volume fraction of Cu nanoparticles. ©, 2014, Zhejiang University. All right reserved.

Harada M.,Nara Womens University | Cong C.,Nanjing University of Technology
Industrial and Engineering Chemistry Research | Year: 2016

Microwave-assisted polyol synthesis of monometallic Pd, Rh, Ru, and Pt nanoparticles has been demonstrated by the use of ethylene glycol and glycerol as a reducing agent in the presence of poly(N-vinyl-2-pyrrolidone) (PVP). The size and morphology of the synthesized nanoparticles have been investigated by means of high-resolution transmission electron microscopy (HRTEM) and extended X-ray absorption fine structure (EXAFS). A comparison between batch scale-up and continuous-flow processing for the microwave-assisted polyol synthesis has been also indicated in terms of the size and morphology of various nanoparticles. In the single-mode MW-assisted continuous-flow processing (10 mL processing volume), the well-dispersed colloidal nanoparticles with a metal concentration equal to ∼10 mM were successfully produced in a sealed glass reactor at boiling temperature of the solvent at a flow rate of 1 mL/min. Furthermore, in the multimode MW-assisted batch processing, the colloidal nanoparticles appeared to have a narrower size distribution in ethylene glycol than in glycerol. The availability of the size regulation (i.e., particle size, size distribution) is discussed. © 2016 American Chemical Society.

Shao J.,Nanjing University of Technology | Yan X.,Carnegie Mellon University | Shao S.,McMaster University
Journal of Mathematical Biology | Year: 2013

The identification of gene coding regions of DNA sequences through digital signal processing techniques based on the so-called 3-base periodicity has been an emerging problem in bioinformatics. The signal to noise ratio (SNR) of a DNA sequence is computed after mapping the DNA symbolic sequence into numerical sequences. Typical mapping schemes include the Voss, Z-curve and tetrahedron representations and the like, which have been used to construct gene coding region detecting algorithms. In this paper, an extended definition of SNR is proposed, which has less computational cost and wider applicability than its original ones. Furthermore, we analyze the SNRs of different mapping schemes and derive the general relationship between Voss based SNR and that of its general affine transformations. We conclude that the SNRs of Z-curve and tetrahedron map are also linearly proportional to that of Voss map. Not only is our conclusion instructional for the design of other affine transformations, but it is also of much significance in understanding the role of the symbolic-to-numerical mapping in the detection of gene coding regions. © 2012 Springer-Verlag.

Zheng X.M.,Nanjing University of Technology
Applied Mechanics and Materials | Year: 2014

This paper describes an unconventional overall design of eight-rotor aerial robot. An INS/GPS based Kalman Filter solution is introduced in attitude estimate to meet the high precision and reliability requirement. In order to coordinate the contradiction between high load and high frequency, we present a new control method for multi-rotor aerial robot, witch take decoupling control on lift rotors and attitude control rotors. Results of simulation and flight test show that our design on aerial robot is effective. © (2014) Trans Tech Publications, Switzerland.

Wang B.,Qingdao University of Science and Technology | Wu X.,Nanjing University of Technology
Journal of Computational Physics | Year: 2014

In this paper we consider multi-frequency highly oscillatory second-order differential equations x ″(t) + M x(t) = f(t, x(t), x '(t)) where high-frequency oscillations are generated by the linear part M x(t), and M is positive semi-definite (not necessarily nonsingular). It is known that Filon-type methods are effective approach to numerically solving highly oscillatory problems. Unfortunately, however, existing Filon-type asymptotic methods fail to apply to the highly oscillatory second-order differential equations when M is singular. We study and propose an efficient improvement on the existing Filon-type asymptotic methods, so that the improved Filon-type asymptotic methods can be able to numerically solving this class of multi-frequency highly oscillatory systems with a singular matrix M. The improved Filon-type asymptotic methods are designed by combining Filon-type methods with the asymptotic methods based on the variation-of-constants formula. We also present one efficient and practical improved Filon-type asymptotic method which can be performed at lower cost. Accompanying numerical results show the remarkable efficiency. © 2014 Elsevier Inc.

Xiao R.,Nanjing Southeast University | Chen L.,Nanjing University of Technology | Saha C.,Monash University | Zhang S.,Nanjing Southeast University | Bhattacharya S.,Monash University
International Journal of Greenhouse Gas Control | Year: 2012

Chemical looping combustion (CLC) of coal is established as a new concept for inherent CO 2 separation with the advantages of low cost and high conversion efficiency. A pilot-scale unit consisting of two fluidized bed reactors was constructed and operated to study the performance of pressurized chemical-looping combustion (PCLC). Experiments were conducted using Shenhua bituminous coal as fuel and MAC iron ore as oxygen carrier at three different operation pressures (0.1, 0.3 and 0.5MPa) and the unit has been operated for totally 19h with steady coal-feeding, about 13.5h of which were realized under stable operation. The results showed that PCLC of coal demonstrated many remarkable advantages over the conventional CLC of coal, in terms of the improvement of carbon conversion in the fuel reactor, CO 2 concentration of exhaust gas and combustion efficiency. At the operating pressure of 0.5MPa, the CO 2 concentration, carbon conversion and combustion efficiency reached very high values of 97.2, 84.7 and 95.5% respectively. The potential of low-cost iron ore as oxygen carrier for commercial coal-fueled CLC unit was also examined. The loss of oxygen carrier due to fine particles leaving the reactors increased with the increase of operation pressure and no agglomeration of oxygen carrier particles occurred during these tests. The oxygen carrier used in PCLC tests were also characterized by SEM-EDX and BET analysis to further emphasis on the effects of operation pressures and runtime. © 2012 Elsevier Ltd.

Wang D.,Soochow University of China | Yu X.,Soochow University of China | Gongyuan W.,Soochow University of China | Gongyuan W.,Nanjing University of Technology
Applied Microbiology and Biotechnology | Year: 2013

In this study, batch processes of pullulan production by Aureobasidium pullulans CCTCC M 2012259 under different pH environments were evaluated. The pH of the medium decreased quickly to an acid stress condition under batch fermentation without pH control. A higher pullulan production was always obtained with a lower biomass under a given glucose concentration with constant pH control, and vice versa. Based on the nonlinear regression analysis of the results obtained from diverse pH control modes, a constant controlled pH of 3.8 was predicted as an optimum pH for efficient pullulan production using a one-element cubic equation. A maximum pullulan concentration of 26.8 g/L and a minimum biomass of 8.1 g/L were achieved under the optimal pH of 3.8, which were in good agreement with the results predicted by the mathematical model. Further information on the physiological characteristics of A. pullulans CCTCC M 2012259 such as intracellular pH, NADH/NAD+, ATP/ADP, and glutathione generation under moderate or severe acidic conditions were investigated, and the results presented more evidence on why pullulan biosynthesized with high efficiency under moderate acid stress (e.g., pH 3.8), which would also help us to better understand the response of the cells to acid stress. © 2013 Springer-Verlag Berlin Heidelberg.

Zhu Y.,University of Shanghai for Science and Technology | Zhang Y.,Wuhan University | Wu C.,Leibniz Institute of Polymer Research | Fang Y.,Nanjing University of Technology | And 2 more authors.
Microporous and Mesoporous Materials | Year: 2011

The zirconium (Zr) containing mesoporous bioactive glasses (MBGs) scaffolds with different Zr contents have been prepared by the combination of polyurethane sponge and P123 surfactant as co-templates and evaporation-induced self-assembly (EISA) process using Ca, P, Si and Zr sources. The study showed that the Zr incorporation in the MBGs scaffolds enhanced the compressive strength, decreased the dissolution, maintained a more stable pH environment, and kept the apatite formation ability. Furthermore, the Zr incorporation provided a better environment for BMSCs attachment, spreading and proliferation on these MBGs scaffolds. Therefore, the Zr incorporated MBGs scaffolds have more potential for use in bone tissue engineering application. © 2011 Elsevier Inc. All rights reserved.

Leng Y.,Jiangnan University | Wu J.,Jiangnan University | Jiang P.,Jiangnan University | Wang J.,Nanjing University of Technology
Catalysis Science and Technology | Year: 2014

A novel amphiphilic POM-paired ionic copolymer was prepared by the anion-exchange of a newly task-specific designed functionalized-ionic liquid copolymer with H3PW4O16, and characterized by FT-IR, SEM, TG, 1H NMR, and elemental analysis. This catalyst was not only capable of catalyzing the epoxidation of alkenes in a liquid-liquid-solid triphase reaction system, showing high catalytic conversions and selectivity, but also avoids the use of chlorinated solvents. After reaction, the catalyst can be conveniently recovered and steadily reused without the change of catalyst structure. The unique amphiphilic catalyst structure is revealed to be responsible for the catalyst's excellent performances in the epoxidation of alkenes with H2O2 by accelerating the mass transfer. © the Partner Organisations 2014.

Zhang C.,Yangzhou University | Pan X.,Yangzhou University | Wang F.,Yangzhou University | Liu X.,Nanjing University of Technology
Fuel | Year: 2012

The Brönsted acidic ionic liquids N-carboxymethylpyridine hydrosulphate ([CH 2COOHPy][HSO 4]) and N- carboxyethylpyridine hydrosulphate ([(CH 2) 2COOHPy] [HSO 4]) were synthesized and used as the extractant and catalyst for the extractionoxidation desulfurization of model oil. The structures of the ILs were confirmed by 1H NMR and 13C NMR. The density, viscosity and acid strength of the ILs were also investigated. The acid strength was in order of H 2SO 4 (98%) [CH 2COOHPy] [HSO 4] > [(CH 2) 2COOHPy][ HSO 4]. The [CH 2COOHPy][HSO 4] showed better activity during the removal of dibenzothiophene (DBT) in n-octane by a combination of extraction and oxidation, and the sulfur removal reached 99.9% under the conditions of V model oil = 20 mL, V IL = 1.2 mL, T= 30 °C and H 2O 2/S molar ratio (O/S) = 6. In the same conditions, the removal of benzothiophene (BT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) by using [CH 2COOHPy][HSO 4] reached 82.5% and 89.1%, respectively. Ionic liquid [CH 2COOHPy][HSO 4] can be recycled 9 times without a significant decrease in the sulfur removal. © 2012 Elsevier Ltd. All rights reserved.

Chen F.-J.,Nanjing University | Xu Y.,Nanjing University of Technology | Du H.-B.,Nanjing University
Angewandte Chemie - International Edition | Year: 2014

Zeolites with extra-large pores have attracted great attention because of their important applications such as in hydrocracking, catalysis, and separation of large molecules. Despite much progress has been made during the past decades, the synthesis of these materials remains a big challenge. A new extra-large-pore zeolite NUD-1 (Nanjing University Du's group zeolite no. 1) is synthesized by using an approach based on supramolecular self-assemblies of small aromatic organic cations as structure-directing agents. NUD-1 possesses interconnecting 18-, 12-, and 10-membered ring channels, built from the same building units as those of ITQ-33 and ITQ-44. There coexist single 3-membered ring, double-3-membered ring and double-4-membered ring secondary building units in NUD-1, which have not been seen in any other zeolites. Extra-large-pore molecular sieves: An extra-large-pore zeolite (NUD-1) was synthesized by using an approach based on supramolecular self-assemblies of small aromatic organic structure-directing cations (see picture). The zeolite possesses interconnecting 18-, 12-, and 10-membered ring channels, built from the same building units as those of the zeolites ITQ-33 and ITQ-44. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Yao M.-X.,Nanjing University | Yao M.-X.,Nanjing University of Technology | Zheng Q.,Nanjing University | Qian K.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Chemistry - A European Journal | Year: 2013

By using the node-and-spacer approach in suitable solvents, four new heterotrimetallic 1D chain-like compounds (that is, containing 3d-3d'-4f metal ions), {[Ni(L)Ln(NO3)2(H2O)Fe(Tp*)(CN) 3]·2 CH3CN·CH3OH}n (H2L=N,N'-bis(3-methoxysalicylidene)-1,3-diaminopropane, Tp*=hydridotris(3,5-dimethylpyrazol-1-yl)borate; Ln=Gd (1), Dy (2), Tb (3), Nd (4)), have been synthesized and structurally characterized. All of these compounds are made up of a neutral cyanide- and phenolate-bridged heterotrimetallic chain, with a {-Fe-C≡N-Ni(-O-Ln)-N≡C-}n repeat unit. Within these chains, each [(Tp*)Fe(CN)3] - entity binds to the NiII ion of the [Ni(L)Ln(NO 3)2(H2O)]+ motif through two of its three cyanide groups in a cis mode, whereas each [Ni(L)Ln(NO3) 2(H2O)]+ unit is linked to two [(Tp*)Fe(CN)3]- ions through the NiII ion in a trans mode. In the [Ni(L)Ln(NO3)2(H 2O)]+ unit, the NiII and LnIII ions are bridged to one other through two phenolic oxygen atoms of the ligand (L). Compounds 1-4 are rare examples of 1D cyanide- and phenolate-bridged 3d-3d'-4f helical chain compounds. As expected, strong ferromagnetic interactions are observed between neighboring FeIII and NiII ions through a cyanide bridge and between neighboring NiII and LnIII (except for NdIII) ions through two phenolate bridges. Further magnetic studies show that all of these compounds exhibit single-chain magnetic behavior. Compound 2 exhibits the highest effective energy barrier (58.2 K) for the reversal of magnetization in 3d/4d/5d-4f heterotrimetallic single-chain magnets. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Kang Q.,Hunan University | Kang Q.,Japan International Center for Materials Nanoarchitectonics | Chen Y.,Hunan University | Li C.,Hunan University | And 3 more authors.
Chemical Communications | Year: 2011

Ultrasensitive photoelectrochemical immunoassay of polycyclic aromatic hydrocarbon (PAH) is proposed using an antibody-modified nanostructured TiO 2 electrode combined with bifunctional gold nanoparticles modified with the PAH antigen and horseradish peroxidase (HRP). The HRP-catalyzed reaction prompts the electron transfer between the electrode and electrolyte causing an excellent photocatalytic performance. © 2011 The Royal Society of Chemistry.

Ko S.-K.,Yonsei University | Chen X.,Ewha Womans University | Chen X.,Nanjing University of Technology | Yoon J.,Ewha Womans University | Shin I.,Yonsei University
Chemical Society Reviews | Year: 2011

Fluorescent probes have been used extensively to monitor biomolecules and biologically relevant species in vitro and in vivo. A new trend in this area that has been stimulated by the desire to obtain more detailed information about the biological effects of analytes is the change from live cell to whole animal fluorescent imaging. Zebrafish has received great attention for live vertebrate imaging due to several noticeable advantages. In this tutorial review, recent advances in live zebrafish imaging using fluorescent probes, such as fluorescent proteins, synthetic fluorescent dyes and quantum dots, are highlighted. © 2011 The Royal Society of Chemistry.

Xiao T.,Nanjing University | Shi K.,Nanjing University of Technology | Yang D.,Nanjing University
International Journal of Production Economics | Year: 2010

This paper investigates coordination of a supply chain consisting of one manufacturer and one retailer facing consumer return. We integrate consumer returns policy and manufacturer buyback policy within a modeling framework and explicitly model the positive effect of refund amount on demand and its negative effect on the probability that consumers keep the products. We design a buyback/markdown money contract to coordinate the supply chain under partial refund policy and find that the refund amount plays an important role in the decisions and profitability of the players. In the coordinated setting with given buyback price, the refund amount first increases the players' expected profits/quantity, and then decreases them. When the risk (variance) of the consumer's valuation increases, the manufacturer may raise the unit wholesale price to achieve a higher unit profit. The supply chain is better off using full refund policy if the risk is very small; otherwise, the supply chain prefers no returns policy. The results of this paper are robust to distribution form. © 2009 Elsevier B.V. All rights reserved.

Fang N.,Utah State University | Jingui L.U.,Nanjing University of Technology
International Journal of Engineering Education | Year: 2010

A decision tree model has been developed to predict student performance in Engineering Dynamics based on 750 data records collected from 125 students in two semesters. The predictor variables include a student's cumulative GPA and scores in four prerequisite courses: Engineering Statics, Calculus I, Calculus II, and Physics. The model generates nine decision rules and shows that a student's performance in Statics and cumulative GPA play the two most significant roles in governing the student's performance in Dynamics. The prediction accuracy of the model is more than 80%, which is at least 14% higher than that of the traditional multivariate regression model. © TEMPUS Publications.

Dou D.,China University of Mining and Technology | Yang J.,China University of Mining and Technology | Liu J.,China University of Mining and Technology | Zhao Y.,Nanjing University of Technology
Knowledge-Based Systems | Year: 2012

To better equip with a non-expert to carry out the diagnosis operations, a new method for intelligent fault identification of rotating machinery based on the empirical mode decomposition (EMD), dimensionless parameters, fault decision table (FDT), MLEM2 rule induction algorithm and improved rule matching strategy (IRMS) is proposed in this paper. EMD is used to preprocess the vibration signals for mining the fault characteristic information more accurately. Then, dimensionless parameters are extracted from both the decomposed signals in time domain and envelop spectrum in frequency domain respectively to form the conditional attributes of a FDT. Moreover, MLEM2 algorithm is run directly on the FDT to generate decision rules imbedded in the data. To make the following classification process more robust, the IRMS is adopted to resolve the conflicting and non-matching problems. Finally, data of rolling element bearings with four typical working conditions is used to evaluate the performance of the proposed method. The testing result demonstrates that the method has high accuracy and systematically good performance. It is proved to be a convenient, concise, interpretable and reliable way to diagnose bearings' faults. The advantages are also confirmed by the comparisons with the other two approaches, i.e. the principal component analysis (PCA) and probabilistic neural network (PNN) based method as well as the wavelet transform (WT) and genetic algorithm (GA) based one. Furthermore, thank to the FDT working as a data interface, the method is more transplantable, therefore it may be applied to diagnose other types of rotating machines effectively. © 2012 Elsevier B.V. All rights reserved.

Zhu L.-W.,Zhejiang University | Wu B.-H.,Zhejiang University | Wan L.-S.,Zhejiang University | Wan L.-S.,Nanjing University of Technology | Xu Z.-K.,Zhejiang University
Polymer Chemistry | Year: 2014

The breath figure method has emerged as a new self-assembly technique to fabricate ordered porous materials, which show potential applications in many fields, such as size-selective separation membranes. However, it is challenging to customize the structures, especially to precisely tune the pore size in a wide range. Moreover, the relationship between polymer structure and film morphologies is still unknown. In this paper, we report a facile, effective, and controllable way to manipulate the evolution of morphologies of honeycomb films, which is based on the blends of an amphiphilic block copolymer and polystyrenes with hydrophobic end groups. A series of atom transfer radical polymerization (ATRP) initiators with alkyl or fluorinated groups were synthesized for polystyrenes with hydrophobic end groups. Polymerization kinetics confirmed the viability of these ATRP initiators. Surface segregation behaviors of the hydrophobic end groups were demonstrated by measuring the surface chemical composition and surface free energies. We found that the polystyrenes with hydrophobic end groups form ordered films only at high polymer concentration (40-60 mg mL-1); moreover, the use of blends of two types of polystyrenes, one of which has a hydrophobic end group whereas the other has a hydrophilic block, can greatly increase the regularity of the honeycomb films and provide the possibility to fine-tune the pore diameter. Moreover, the evolution of surface morphologies of the films can be ideally correlated with the surface free energies of the end-functionalized polymers. © 2014 the Partner Organisations.

Zhang K.,Nanjing University | Jin C.,Nanjing University of Technology | Sun Y.,Nanjing University | Chang F.,Nanjing University | Huang W.,Nanjing University
Inorganic Chemistry | Year: 2014

A pair of 18-membered [1 + 1] chiral pendant-armed Schiff base macrocyclic mononuclear Pb(II) complexes with an unusual N1O2 coordination mode, synthesized from two chiral isomeric dialdehyde components, can be further self-assembled to one-dimensional ribbon coordination polymers by adding NaOH as a base to remove two phenolic protons. © 2014 American Chemical Society.

Long J.,Fuzhou University | Long J.,Nanyang Technological University | Wang S.,Fuzhou University | Ding Z.,Fuzhou University | And 5 more authors.
Chemical Communications | Year: 2012

An amine-functionalized zirconium metal-organic framework (MOF) was used as a visible-light photocatalyst for selective aerobic oxygenation of various organic compounds including alcohols, olefins and cyclic alkanes, at high efficiency and high selectivity. This study shows the great potential for design and application of MOF-based photocatalysts. © 2012 The Royal Society of Chemistry.

Leng Y.,Jiangnan University | Wang J.,Nanjing University of Technology | Jiang P.,Jiangnan University
Catalysis Communications | Year: 2012

Amino-containing cross-linked ionic copolymer-anchored HPA catalysts were prepared by the anion-exchange of polydivinylbenzene/amino-functionalized ionic liquids copolymers with Keggin heteropoly acid (HPA), and were characterized by 1H NMR, FT-IR, TG, XRD, SEM, TEM, BET surface area, and elemental analysis. Their catalytic performance for oxidation of benzyl alcohol with H 2O 2 was studied under solvent-free conditions. The results demonstrated that the catalysts were very active and selective, and could be reused after simple separation. © 2012 Elsevier B.V.

Zhou J.,Nanjing University of Technology | Liu F.,Shanxi Agricultural University | Pan C.,Shanxi Agricultural University
PLoS ONE | Year: 2014

The effects of the molecular weight (MW) and charge density (CD) of cationic polyacrylamide (CPAM) on sludge dewatering and moisture evaporation were investigated in this study. Results indicated that in sludge conditioning, the optimum dosages were 10, 6, 6, 4, and 4 mg g-1 CPAM with 5 million MW and 20% CD, 5 million MW and 40% CD, 3 million MW and 40% CD, 8 million MW and 40% CD, and 5 million MW and 60% CD, respectively. The optimum dosage of CPAM was negatively correlated with its CD or MW if the CD or MW of CPAM was above 20% or 5 million. In the centrifugal dewatering of sludge, the moisture content in the conditioned sludge gradually decreased with the extension of centrifugation time, and the economical centrifugal force was 400xg. The moisture evaporation rates of the conditioned sludge were closely related to sludge dewaterability, which was in turn significantly correlated either positively with the solid content of sludge particles that were <2 mm in size or negatively with that of particles measuring 1 mm to 2 mm in diameter. During treatment, sludge moisture content was reduced from 80% to 20% by evaporation, and the moisture evaporation rates were 1.35, 1.49, 1.62, and 2.24 times faster in the sludge conditioned using 4 mg g-1 CPAM with 5 million MW and 60% CD than in the sludge conditioned using 4 mg g-1 CPAM with 8 million MW and 40% CD, 6 mg g-1 CPAM with 5 million MW and 40% CD, 6 mg g-1 CPAM with 3 million MW and 40% CD, and 10 mg g-1 CPAM with 5 million MW and 20% CD, respectively. Hence, the CPAM with 5 million MW and 60% CD was ideal for sludge dewatering. © 2014 Zhou et al.

Gao F.,Nanjing University | Zhu F.-F.,Nanjing University | Wang X.-Y.,Nanjing University | Xu Y.,Nanjing University of Technology | And 2 more authors.
Inorganic Chemistry | Year: 2014

After the chemical oxidation of the neutral tetrakis(methylthio) tetrathiafulvalene (TMT-TTF, 1) by specific oxidation agents with weakly coordinating anion, [Al(ORF)4]- [ORF = OC(CF3)3], the radical cation TMT-TTF•+ (1•+) and dication TMT-TTF2+ (12+) were successfully stabilized and isolated. All the compounds are well-soluble in some solvents and have been systematically investigated by absorption spectra, 1H NMR, electron paramagnetic resonance (EPR) measurements. Their crystal structures and electronic properties have been studied in conjunction with theoretical calculation. The synthetic approach for chemical oxidation by specific salts of weakly coordinating anions is useful for stable radical cations of tetrathiafulvalene (TTF) and its derivatives in both solution and solid state, which will extend the further research, including structure-property relations on stable radicals for TTF derivatives and new functional materials based on them. © 2014 American Chemical Society.

Zhu L.-W.,Zhejiang University | Yang W.,Zhejiang University | Ou Y.,Zhejiang University | Wan L.-S.,Zhejiang University | And 2 more authors.
Polymer Chemistry | Year: 2014

Polymers with functional end groups were synthesized via atom transfer radical polymerization (ATRP) using a novel cyclic lactone initiator, which can be facilely converted into ionized and neutralized groups by hydrolysis and acidification processes, respectively. Results from Fourier transform infrared (FTIR) and 1H and 13C nuclear magnetic resonance (NMR) spectroscopies indicate that the cyclic lactone end group can be fully converted into sodium carboxylate in alkaline solution whereas the acidification process induces both neutralization and esterification. Gel permeation chromatography (GPC) curves reveal intramolecular esterification instead of intermolecular esterification during the acidification process. The polymers with various end groups that show different hydrophilicities were then utilized to fabricate honeycomb-patterned porous films by the breath figure method. Polystyrene with an ionized or neutralized end group forms highly ordered self-assembled films in an easy and reproducible way, whereas that with a less hydrophilic lactone end group generates irregular films. Moreover, polystyrene with an ionized end group, which is the most hydrophilic, results in porous films with a multilayered structure and a much smaller surface pore size (it decreases to ∼610 nm from 1.8 μm for films prepared from the neutralized polymer). In addition, we found that the end-functionalized polystyrene with a very low molecular weight (∼2960 g mol-1) is able to form highly ordered honeycomb films. It is speculated that the ionized end group endows polystyrene with high interfacial activity, leading to the unique surface morphologies. This is evidenced from the results of water contact angles on film surfaces with a pincushion structure obtained by removing the top surface layer. The proposed approach to well-controlled end-functionalized polymers is useful in the fabrication of self-assemblies with adjustable morphologies. © the Partner Organisations 2014.

Wang F.,University of Cambridge | Wang H.,Nanjing University of Technology | Al-Tabbaa A.,University of Cambridge
Journal of Hazardous Materials | Year: 2014

The long-term leachability, heavy metal speciation transformation and binding mechanisms in a field stabilised/solidified contaminated soil (made ground) from West Drayton site were recently investigated following in situ auger mixing treatment with a number of cement-based binders back in 1996. Two batch leaching tests (TCLP and BS EN 12457) and a modified five step sequential extraction procedure along with X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were employed for the testing of the 17-year-old field soil. The results of batch leaching tests show that the treatment employed remained effective at 17 years of service time, with all BS EN 12457 test samples and most of TCLP test samples satisfied drinking water standards. Sequential extraction results illustrate that the leaching of Cu, Ni, Zn, Pb and Cd in all mixes mainly occurred at the Fe/Mn phase, ranging from 43% to 83%. Amongst the five metals tested, Ni was the most stable with around 40% remained in the residual phase for all the different cement-based binder stabilised/solidified samples. XRD and SEM analyses show that the hydration process has been fully completed and further carbonation took place. In summary, this study confirms that such cement-based stabilisation/solidification (S/S) treatment can achieve satisfactory durability and thus is a reliable technique for long-term remediation of heavy metal contaminated soil. © 2014 Elsevier B.V.

Zhao X.,Nanjing University of Technology | Zhao X.,Aichi Institute of Technology | Nakagawa T.,Aichi Institute of Technology
International Journal of Systems Science | Year: 2015

It has been assumed for a standby unit that periodic inspection is performed more easily to detect failures, but such a strict periodic mode would be impractical if the unit is executing some procedures without stops. From the above viewpoint, this paper first optimises a random inspection policy in accordance with random procedure times, compares it with periodic inspection and computes a modified checking cost for random inspection to determine the case where such a random inspection would be adopted. Second, this paper proposes three new inspection models in which inspections with deterministic policies are scheduled strategically while their performances need to be limited by completion times of operation procedures. These policies are called inspection first, inspection last and inspection overtime. The total expected inspection and downtime costs of each model until failure detection are obtained, and optimal policies which minimise them are derived analytically. Furthermore, the three inspection policies are compared with periodic inspection, inspection first and last are compared with each other, and a modified checking cost for inspection overtime is discussed when the policy would be better than periodic inspection. © 2013 Taylor & Francis.

Shen M.,Nanjing University of Technology | Ye D.,Northeastern University China
Fuzzy Sets and Systems | Year: 2013

This paper addresses the state feedback control of nonlinear continuous-time, Markovian-jump systems. The nonlinearity is represented by Takagi-Sugeno fuzzy models and the transition probability matrix is assumed to be partly known: some elements in the matrix are known, some are unknown but with known lower and upper bounds, and some are completely unknown. By making full use of the continuous property of the transition probability matrix, new sufficient conditions for the stochastic stability of the system are obtained in terms of linear matrix inequalities. We show that the conditions given are less conservative than or at least the same as those for existing results. Moreover, using the conditions obtained, we establish a method for design of a H ∞ state feedback controller. Numerical examples illustrate the effectiveness of the proposed method. © 2012 Elsevier B.V.

Liu D.,Southwest Jiaotong University | Li T.,Southwest Jiaotong University | Li H.,Nanjing University of Technology
Fundamenta Informaticae | Year: 2012

By considering the levels of tolerance for errors and the cost of actions in real decision procedure, a new two-stage approach is proposed to solve the multiple-category classification problems with Decision-Theoretic Rough Sets (DTRS). The first stage is to change an m-category classification problem (m > 2) into an m two-category classification problem, and form three types of decision regions: positive region, boundary region and negative region with different states and actions by using DTRS. The positive region makes a decision of acceptance, the negative region makes a decision of rejection, and the boundary region makes a decision of abstaining. The second stage is to choose the best candidate classification in the positive region by using the minimum probability error criterion with Bayesian discriminant analysis approach. A case study of medical diagnosis demonstrates the proposed method.

Wu H.,Nanjing University of Technology | Wang S.,Nanjing Southeast University
Journal of Hazardous Materials | Year: 2012

An experiment was conducted in a batch reactor for a real printing and dyeing wastewater pretreatment using Fenton process in this study. The results showed that original pH, hydrogen peroxide concentration and ferrous sulfate concentration affected ORP value and pretreatment efficacy greatly. Under experimental conditions, the optimal original pH was 6.61, and the optimal hydrogen peroxide and ferrous sulfate concentrations were 1.50 and 0.75gL-1, respectively. The relationship among ORP, original pH, hydrogen peroxide concentration, ferrous sulfate concentration, and color (COD or BOD5/COD) was established, which would be instructive in on-line monitoring and control of Fenton process using ORP. In addition, the effects of wastewater temperature and oxidation time on pretreatment efficacy were also investigated. With an increase of temperature, color and COD removal efficiencies and BOD5/COD ratio increased, and they were in proportion to the exponent of temperature reciprocal. Similarly, color and COD removal efficiencies increased with increasing oxidation time, and both color and COD removal obeyed the first-order kinetics. The BOD5/COD ratio could be expressed by a second-degree polynomial with respect to oxidation time, and the best biodegradability of wastewater was present at the oxidation time of 6.10h. © 2012 Elsevier B.V.

Wang C.,Xian University of Science and Technology | Jiang B.,Nanjing University of Technology | Liu M.,General Motors | Ge Y.,Xian University of Science and Technology
Journal of Alloys and Compounds | Year: 2014

A two layer composite coating system was applied on the surface of AZ31B magnesium alloy by Micro-arc Oxidation (MAO) plus electrophoretic coat (E-coat) technique. The Mg sample coated with MAO plus E-coat (MAOE) was compared with bare Mg and Mg sample coated by MAO only. The surface microstructure and cross section of bare and coated Mg before and after corrosion were examined by Scanning Electron Microscopy (SEM). The corrosion performance of bare and coated Mg was evaluated using electrochemical measurement and hydrogen evolution test. The results indicated that the corrosion resistance of AZ31B Mg alloy was significantly improved by MAOE composite coating. The corrosion mechanism of bare and coated Mg is discussed. © 2014, Elsevier B.V. All rights Reserved.

Liu G.-X.,Nanjing Xiaozhuang University | Xu H.,Nanjing Xiaozhuang University | Zhou H.,Nanjing Xiaozhuang University | Nishihara S.,Osaka Prefecture University | Ren X.-M.,Nanjing University of Technology
CrystEngComm | Year: 2012

Four new coordination polymers, namely, [Co(BIPA)(titmb)]·H 2O (1), [Co 3(BIPA) 3(titmb) 2] ·0.73H 2O (2), [Ni(SDBA)(bix)]·2H 2O (3) and [Ni(SDBA)(bix)(H 2O)]·0.38H 2O (4) (H 2BIPA = 5-bromoisophthalic acid, H 2SDBA = 4,4′-dicarboxybiphenyl sulfone, titmb = 1,3,5-tris(imidazol-1-ylmethyl)-2,4,6-tri-methylbenzene, bix = 1,4-bis(imidazol-1-ylmethyl)benzene), were obtained under hydrothermal conditions. Four complexes were characterized by elemental analyses, IR spectra, thermogravimetric analyses and single-crystal X-ray diffraction. Complexes 1 and 2 are polymorphs formed from Co(II) cations, BIPA 2- anions, titmb ligands and water molecules, showing a three-dimensional (3,5)-connected network with the topology of (6 3)(6 9.8) for 1 and a three-dimensional (3,4)-connected coordination framework with the topology of (4.6.8)(4.6 2.8 3)(6.8 5)(6 2.8 3.10)(8 3) for 2. Complexes 3 and 4 are also two polymorphs constructed from Ni(II) cations, SDBA 2- anions, bix ligands and water molecules. Complex 3 exhibits a two-dimensional lamella structure with (4,4) topology, whereas complex 4 displays a two-dimensional 2-fold interpenetrating (6,3) network. It is shown that the reaction temperature plays a crucial role in the formation of the final products. Moreover, the nonlinear optical and ferroelectric properties of 1 have also been investigated. © 2012 The Royal Society of Chemistry.

Rao F.,Nanjing University of Technology
Journal of Statistical Mechanics: Theory and Experiment | Year: 2013

In this paper, we investigate the complex dynamics of a spatial toxic-phytoplankton-zooplankton model with Holling type-II functional response. Through a detailed analytical study of the reaction-diffusion model, we obtain some conditions for local and global stability and for diffusive instability with zero-flux boundary conditions of a positive equilibrium. On the basis of these results, we present the evolutionary processes of pattern formation that involve organism distribution and the interaction of a spatially distributed population with local diffusion. Then, novel numerical evidence of the time evolution of patterns controlled by diffusion and environmental carrying capability in the model are presented, and it is found that the model dynamics exhibits complex pattern replication. Additional studies reveal that pattern formation in the spatially extended model depends on the choice of the initial conditions. These results indicate that the interaction between toxin-producing phytoplankton and zooplankton in marine environments may be partly driven by the forces of diffusion or the environmental carrying capability. © 2013 IOP Publishing Ltd and SISSA Medialab srl.

Xue L.,MMI Engineering Inc. | Widera G.E.O.,Marquette University | Sang Z.,Nanjing University of Technology
Journal of Pressure Vessel Technology, Transactions of the ASME | Year: 2010

In an earlier paper (2009, "Burst Pressure of Pressurized Cylinders With the Hillside Nozzle," ASME J. Pressure Vessel Technol., 131(4), p. 041204), an elastic-plastic large deflection analysis method was used to determine the burst pressure and fracture location of hillside cylindrical shell intersections by use of nonlinear finite element analysis. To verify the accuracy of the finite element results, experimental burst tests were carried out by pressurizing test vessels with nozzles to burst. Based on the agreement between the numerical simulations and experimental results of Wang et al. (2009, "Burst Pressure of Pressurized Cylinders With the Hillside Nozzle," ASME J. Pressure Vessel Technol., 131(4), p. 041204), a parametric study is now carried out. Its purpose is to develop a correlation equation by investigating the relationship between various geometric parameters (d/D, D/ T, and t/ T) and the burst pressure. Forty-seven configurations, which are deemed to cover most of the practical cases, are chosen to perform this study. In addition, four different materials are employed to verify that the proposed equation can be employed for different materials. The results show that the proposed equation resulting from the parametric analysis can be employed to predict the static burst pressure of cylindrical shell intersections for a wide range of geometric ratios. Copyright © 2010 by ASME.

Zhang Y.,Nanjing University of Technology | Sun Y.,Nanjing University of Finance and Economics | Chen Z.,Nanjing University
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2013

To put forward feedback information of the scenario simulation model for the references of land use planning decision, we reviewed and analyzed the land use characteristics (1996-2009) in Xinbei district of Changzhou, and extracted three important types of land use: cultivated land, construction land and rural residential land. Typical relation analysis method and spatial gridding Logistic regression analysis method were used to made quantitative analysis of these three types of driving forces and obtain the main influential driving forces for each land use. Based on the analysis of land use characteristics and driving forces, the study built land use scenario characteristic system from three aspects which included political characteristics, global characteristics and spatial characteristics, and expressed land use scenario characteristics quantitatively. The MAS technology was introduced to construct an agent-based land use scenario simulation model, and using the development platform of Eclipse+Swarm, realize the land use scenario simulation model. The results showed that the changes of structure in Xinbei district were increasingly complicated; reduction of agricultural land contributed most to the increase of urban land. In term of spatial arrangement, the changes of land use types were the greatest in the study areas of eastern or southeastern parts along the administrative region boundary, or the Yangtze River catchment. 1) The results showed that fitting degree of the spatial global simulation was high, that of construction land, rural residential land and cultivated land was 78.45%, 99.85%, 98.35% separately, and fitting simulation of spatial variation for construction land, rural residential land and cultivated land was 55.18%, 0.02%, 69.11% separately. 2) The study set three scenarios of socio-economic development (with high, medium and low developing speed) and simulated the land use changes from 2006 to 2020. The results showed that in the three scenarios, the construction land would increase 3788.44, 2922.83 and 2114.64 hm2; the cultivated land would increase 1106.60, 858.61 and 592.35 hm2; the rural residential land would increase 5378.72, 4817.03 and 4238.97 hm2. In the scenario I, the urbanization would go fast, the urban-rural land convertion would be obvious, and the renovation and reconstruction of the rural residential land would enhanced; in the scenario II, the urban expansion and population growth would slow down, and the cultivated land loss would be decrease; in the scenario III, the urban-rural land convertion would decrease obviously, and the cultivated land loss would be prevented effectively. 3)The compactness analysis under the three scenarios showed that the compact degree would be low in the scenario I (construction land, rural residential land and cultivated land was 0.0059, 0.0036, 0.0024, separately)and in the scenario III (construction land, rural residential land and cultivated land was 0.0057, 0.0031, 0.0024, separately), but high in the scenario II(construction land, rural residential land and cultivated land was 0.0061, 0.0034, 0.0022 separately); the rural residential land would be dispersive in the scenario III and the renovation of the rural villages would be the least in the scenario II.

Ding Z.,Nanjing University of Technology | Hu X.,Nanjing University
Environmental Geochemistry and Health | Year: 2014

In order to investigate the ecological and human health risks of metal(loid)s (Cu, Pb, Zn, Ni, Cd, Mn, Cr, and As) in peri-urban soils, 43 surface soil samples were collected from the peri-urban area around Nanjing, a megacity in China. The average contents were 1.19, 67.8, 37.6, 105, 167, 44.6, 722, and 50.8 mg kg-1 for Cd, Cr, Ni, Pb, Zn, Cu, Mn, and As, respectively. A significant positive correlation was found between Cu, Pb, Zn, Cd, Mn, and As (p < 0.01), and Cr had a significant positive correlation with Ni (p < 0.01). Geoaccumulation indices indicate the presence of Cd and As contamination in all of the peri-urban soil samples. Potential ecological risk indices show that the metal(loid)s in the soil could result in higher ecological risks. Cd is the main contributor to the risk, followed by As. The levels of Cu, Pb, Zn, Cd, Mn, and As in stomach and intestinal phases show a positive linear correlation with their total contents. Mn, Zn, Ni, Cd, and Pb in stomach phase showed higher bioaccessibility, while in intestinal phase, Cu, Cr, and As had the higher bioaccessibility. The carcinogenic risk in children and adults posed by As, Pb, and Cr via ingestion was deemed acceptable. The non-carcinogenic risks posed by these metal(loid)s via ingestion to children are higher than to adults and mainly result from As. © 2013 Springer Science+Business Media Dordrecht.

Zeng Y.,Yangzhou University | Zhu X.,Yangzhou University | Yuan Y.,Yangzhou University | Zhang X.,Yangzhou University | Ju S.,Nanjing University of Technology
Separation and Purification Technology | Year: 2012

We use Grand Ensemble Monte Carlo (GCMC) simulations to study the adsorption of thiophene and benzene in Cu-BTC and IRMOF-1 metal-organic frameworks (MOFs). We calculated the adsorption isotherms of pure components and analyze the sitting of the molecules in the two types of structure for the different adsorption pressure. The simulations show that electrostatic interactions between adsorbate and MOF atoms dominate the adsorption mechanism. The bulk compositions of 10:90, 50:50 and 90:50 for thiophene-benzene were studied. The results show that thiophene molecules are preferentially adsorbed over benzene molecules in the pressure range under study for IRMOF-1 while preferentially adsorbed over benzene in the low pressure range for Cu-BTC. IRMOF-1 has a significantly higher adsorption capacity than Cu-BTC, while the adsorption selectivity of thiophene over benzene is observed to be higher in the latter at low pressure, which proves that the separation efficiency is largely affected by shape and nature of linkers of structure. © 2012 Elsevier B.V. All rights reserved.

Yang X.,Nanjing University of Technology | Lira C.T.,Michigan State University
Chemical Engineering Journal | Year: 2012

The simplified local density (SLD) approach using the Elliott, Suresh, Donohue (ESD) equation of state is developed to model the adsorption on porous activated carbons by consideration of the pore size distribution (PSD). The SLD-ESD approach is used to calculate the local adsorption amount for a given pore width. The total adsorption on porous materials is the sum of all local adsorption amounts over entire range of pore structure sizes. The adsorption of a pure component can be fitted well by this SLD-ESD model for a wide temperature range. The reasonability and reliability of PSDs obtained from different gas probes are characterized. The PSDs determined by the adsorption data of pure components have been used to predict the adsorption equilibria of binary mixtures. By applying to different systems for wide conditions, the predictive capacity of this model was examined. It is shown that the SLD-ESD theoretical model in conjunction with PSD analysis can provide a reasonable prediction for mixture adsorption. © 2012 Elsevier B.V.

Liu J.-C.,Nanjing University of Technology | Lei G.H.,Hohai University
Computers and Geotechnics | Year: 2013

Fully drained and undrained boundary conditions are commonly applied to solve the consolidation problems. In most practical situations, however, impeded drainage boundaries are really a matter of great concern. As an attempt to idealize such boundary conditions, a time-decaying exponential function has recently been suggested to describe the changes of excess pore water pressure at the boundaries of consolidating soils subjected to instantaneous loading. It allows the excess pore water pressure to dissipate smoothly rather than abruptly from its initial value given by the instantaneous loading to the value of zero, leading to an exponentially time-growing drainage boundary. In this study, a numerical solution of one-dimensional consolidation of layered soils with such defined boundaries is derived by using the method of Laplace transform and its numerical inverse. The solution is explicitly expressed and conveniently coded into a computer program for ease and efficiency of practical use. Analytical solutions of one-dimensional consolidation of single-layered soil are also derived by using the method of analytical inverse Laplace transform and the method of separation of variables as well. By comparing these two analytical solutions and comparing with an available analytical solution for two-layered soil with pervious boundaries, the proposed numerical solution for layered soils is validated. Good agreement is obtained, and the accuracy of the numerical solution is verified. Moreover, the dissipation of excess pore water pressure and the increase of degree of consolidation with time for a four-layered soil are investigated to assess the effects of the adopted drainage boundary conditions on consolidation. © 2013 Elsevier Ltd.

Zhang N.,Nanjing University of Technology | Fu C.C.,University of Maryland University College | Che H.,Southwest Jiaotong University
Engineering Structures | Year: 2011

Curved prestressed concrete structures with unbonded tendons are widely used in highway interchanges and industrial cooling towers, etc. In engineering practice, there is a demand to establish calculating methods for analyzing and designing these prestressed concrete curved structures with unbonded tendons. However, there are some difficulties in calculating the ultimate strength of these curved structures. The major difficulty is to calculate the ultimate stress in unbonded tendons. The assumption of a plane cross-section cannot be adopted here because of the slip between unbonded tendon and concrete. Thus, many formulas for calculating the ultimate stress in unbonded tendons were mainly based on experimental data fitting. In order to obtain the ultimate stress in unbonded tendons from mechanical principles, instead of using experimental data fitting formula, an advanced nonlinear analysis method to calculate ultimate stress in unbonded tendons is developed. The analysis model is established by using the Reissner-Mindlin medium thickness plate theory allowing for the influence of the transverse shear deformation. The orthotropic increment constitutive model of concrete is extended to solve the medium thickness plate problem. The tension stiffening of the cracked concrete is considered in the nonlinear analysis model. The numerical formulation of calculating the stress increment in an unbonded tendon is established by using the spatial displacement relationship. Instead of using general-purpose programs such as ANSYS and ABAQUS, a computer program specifically for predicting the nonlinear response of a prestressed concrete curved slab structure with unbonded tendons and calculating the ultimate stress in unbonded tendons is developed by authors. Six test models of prestressed concrete curved slabs with unbonded tendons are reported. The calculated results using this program are compared with test results, where their relative deviation is less than 3.0%, which validates the proposed method. These study results can be used for analysis, especially to design the strength of prestressed concrete curved structures with unbonded tendons. And, this research work also proposes a new approach, which can be customized to fit into general purposed FEM programs, such as APDL (ANSYS Parametric Design Language), for analyzing the nonlinear structural behavior of these curved structures. © 2010 Elsevier Ltd.

Yue J.,Nanjing University of Technology
Tumu Gongcheng Xuebao/China Civil Engineering Journal | Year: 2015

Seismic damage of the structures normally begins at material level, develops at section, member, storey and structure levels, and finally ends at the global structural failure state. In order to study the damage evolution law of the structure, the deformation equivalent principle and generalized force-deformation relation are proposed. Thus, the multi-level seismic damage model is developed and shows consistent mechanical characteristic for every structural level. The multi-level seismic damage performance standard is proposed based on the general damage behavior of each structural level and generalized force-deformation relation. Furthermore, the limit damage value and critical performance indicators are defined. A normalized parameter is introduced to adjust the corresponding relation between the multi-level seismic damage model and performance. On the basis of extensive experimental data and numerical simulation results, the above relationships of each limit state are analyzed and the normalized parameters are obtained by numerical regression method. By the proposed multi-level damage model combined with performance standard, the calculated damage evolutions can correctly show the entire damage process and damage state for each structural level, which is a theoretical basis to reveal the inherent law of structural seismic damage performance. ©, 2015, Editorial Office of China Civil Engineering Journal. All right reserved.

Zhou W.-L.,Tonghua Normal University | Xu Y.,Nanjing University of Technology
Chinese Journal of Inorganic Chemistry | Year: 2011

A diethylenetriamine templated holmium sulfate (H3dien)[Ho(SO4)3(H2O)2] (dien=diethylenetriamine) (1) with a single chain structure has been synthesized solvothermally and the structure has been characterized by single-crystal X-ray diffraction, IR, TGA, ICP and XRD. Single crystal X-ray diffraction illuminates that the compound 1 crystallizes in the monoclinic crystal system, space group P21/c with cell dimension: a=0.66020(13) nm, b=1.4767(3) nm, c = 1.6556(3) nm, β=93.313(2)°, V=1.6114(5) nm3, Z=4. Crystal analysis of compound 1 shows a single chain constructed from HoO8 polyhedra and SO4 tetrahedra. Coordination water molecules link adjacent chains by using hydrogen bonds to generate 3D supermolecule structure assembly along a axis, whereas the organic amines are located between the chains. And also, during the formation of 1, the pH value (1.5) plays an important role. CCDC: 841765.

Shao Z.,Nanjing University of Technology
Progress in Chemistry | Year: 2011

Solid oxide fuel cells (SOFCs) are a type of electrochemical energy conversion devices with high efficiencies and low emissions. The practical application of SOFCs technology would have a great environmental benignity and be beneficial for a sustainable development of the world. The decrease of operation temperature can accelerate the commercialization of SOFCs technology, the key is the development of high performance of cathodes operated at low temperature. In this paper, we mainly have a comprehensive introduction on the progress in developing of novel cathodes for reduced temperature SOFCs, including perovskite-type Ba0.5Sr0.3Co 0.8Fe0.2O3-8, double perovskite-type LnBaCo2O5+8, other perovskite-type cobalt-based mixed conducting electrodes, non-cobaltrelated mixed conducting oxide electrodes, precious metal modified oxide electrodes and nano-structured composite electrodes prepared by infiltration, and specific cathodes for proton-conducting SOFCs. More attentions are paid to the development in our lab within the last five years. The development trend of cathode in SOFCs is proposed.

Ji B.,Nanjing Southeast University | Ji B.,Nanjing University of Technology | Wang J.,Nanjing Southeast University | Zhao J.,Nanjing Southeast University
IEEE Transactions on Industrial Electronics | Year: 2013

The main contribution of this paper is the derivation rules summarized from existing high-performance inverters with H6-type configuration, which makes novel topologies possible. In addition, a novel high-efficiency single-phase transformerless photovoltaic inverter with hybrid modulation method is also proposed and evaluated as an example. Without input split capacitors, common-mode voltage and leakage current issues in a nonisolated system with H6-type configuration are eliminated, and the feature of a three-level output voltage in the inverter bridge's middle point helps inductors and power quality optimization. The detailed operation principles with hybrid modulation strategy combined with unipolar and bipolar pulsewidth modulation schemes are presented. Experimental results of a 2200VA prototype verify the proposed topology with hybrid modulation method. © 2012 IEEE.

Yang J.,Shanghai University | Ni B.,Shanghai University | Liu J.,Nanjing Medical University | Zhu L.,Shanghai University | Zhou W.,Nanjing University of Technology
Spine Journal | Year: 2011

Background context: Epidural adhesion and fibrosis attribute to the prevalence of pain in normal wound healing after laminectomy surgery. Hydroxycamptothecin (HCPT), an antitumor drug, has proved to be effective in preventing fibroblast proliferation and reducing epidural adhesion after laminectomy in vivo animal study. However, HCPT's disadvantages, such as poor solubility and short half-life, limit its application clinically. Compared with HCPT, the liposome-encapsulated HCPT (L-HCPT) could reduce epidural fibrosis by preventing the proliferation of fibroblast in the scar tissues with longer half-life and increased solubility. Purpose: To evaluate the suitability of L-HCPT in the laminectomy models on rabbits and to explore the mechanisms in the prevention of epidural scar formation. Study design: An original investigation that characterizes the novel delivery system in the combinational application of HCPT and liposome (L-HCPT). Patient sample: The sample comprises 24 mature New Zealand white adult rabbits. Methods: Lumbar laminectomies at L4 and L6 with an L5 disc injury were performed on 24 mature New Zealand white adult rabbits. The rabbits were then randomized into three groups. In Group I, the laminectomy site was treated with a cotton pad soaked with HCPT solution (1 mg/mL) for 5 minutes (HCPT group) and was flushed with saline completely. In Group II, 1 mL of L-HCPT was seeded on the laminectomy area (L-HCPT group). In Group III, the laminectomy area was flushed with saline before wound closure (control group). After 28 days, the animals underwent magnetic resonance imaging. The animals were euthanized; the spinal section was removed for macroscopic evaluation, and hydroxyproline in the scar tissue was quantified. Results: Operation in all the animals yielded a reproducible laminectomy, without complication or mortality. In the laminectomy sites treated with L-HCPT, the dura mater was clean without any evident adhesion. Magnetic resonance imaging analysis implied that L-HCPT treatment could reduce the epidural scar significantly compared with saline control group, which was further proved by the decreased concentration of hydroxyproline in the scar tissues. Conclusion: These results demonstrate that the treatment of postlaminectomy wounds in rabbits with L-HCPT reduces the severity of adhesion. © 2011 Elsevier Inc. All rights reserved.

Wang W.,Curtin University Australia | Tade M.O.,Curtin University Australia | Shao Z.,Curtin University Australia | Shao Z.,Nanjing University of Technology
Chemical Society Reviews | Year: 2015

Meeting the growing global energy demand is one of the important challenges of the 21st century. Currently over 80% of the world's energy requirements are supplied by the combustion of fossil fuels, which promotes global warming and has deleterious effects on our environment. Moreover, fossil fuels are non-renewable energy and will eventually be exhausted due to the high consumption rate. A new type of alternative energy that is clean, renewable and inexpensive is urgently needed. Several candidates are currently available such as hydraulic power, wind force and nuclear power. Solar energy is particularly attractive because it is essentially clean and inexhaustible. A year's worth of sunlight would provide more than 100 times the energy of the world's entire known fossil fuel reserves. Photocatalysis and photovoltaics are two of the most important routes for the utilization of solar energy. However, environmental protection is also critical to realize a sustainable future, and water pollution is a serious problem of current society. Photocatalysis is also an essential route for the degradation of organic dyes in wastewater. A type of compound with the defined structure of perovskite (ABX3) was observed to play important roles in photocatalysis and photovoltaics. These materials can be used as photocatalysts for water splitting reaction for hydrogen production and photo-degradation of organic dyes in wastewater as well as for photoanodes in dye-sensitized solar cells and light absorbers in perovskite-based