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.


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Patent
Nanjing University of Technology | Date: 2014-09-12

The present invention relaters to a method for continuously preparing a nano zinc oxide with a membrane reactor. A zinc salt solution and a precipitator solution required for the preparation of a zinc oxide are respectively used as dispersion phases, and under the action of a certain pressure, the two reaction solutions respectively penetrate through a membrane tube at a certain rate and disperse quickly under the action of a shear force and react, producing a precursor precipitate. A precursor suspension penetrates through the membrane tube continuously and circularly after being pressurized by a pump, and at the same time, deionized water as a washing fluid is added to a suspension storage tank, wherein impurity ions penetrate through membrane pores and are discharged along with the liquid medium; after the concentration of the impurity ions meets requirements, the concentrated solution is discharged continuously and then spray-dried to obtain a basic zinc carbonate precursor powder. The basic zinc carbonate powder is calcined under certain conditions to obtain the nanostructured zinc oxide powder. The continuous preparation and washing of a powder can be achieved by coupling a membrane washing technique with a membrane dispersion technique. The procedure is simple, the structure of zinc oxide is easy to control and the yield is high.


Patent
Nanjing University and Nanjing University of Technology | Date: 2014-10-16

The present invention discloses a device for Fenton fluidized-bed process and a method applying the device for wastewater treatment. It belongs to the wastewater treatment field. The device comprises an adjusting tank, a lift pump and a main reaction column. The adjusting tank is connected to a water distributing trough on the top of the main reaction column through the lift pump; the main reaction column is filled with the packing material, and below the packing material is equipped with an obcone, whereon a plurality of inlets are provided and a slag discharge pipe is connected to the bottom; above the packing material is installed an inclined plate, above which and at the upper end of the main reaction column are arranged with a partitioned trough and an outflow trough; the partitioned trough is evenly divided by a vertical plate into two independent chambers; the upper end of each chamber is connected to the water distributing trough while the lower end of each chamber is designed with an outlet; the outlets of the two independent chambers are connected to the inlets on the obcone through the first circulation pump and the second circulation pump respectively; the outflow trough is installed opposite the partitioned trough. When being used to treat biotreated wastewater, the device disclosed in the present invention can enhance use efficiency of the reagent, and maintain high effect and stability in eliminating iron in the wastewater.


Patent
Nanjing University, Nanjing University of Technology and Est Water And Technologies Co. | Date: 2014-11-18

A water reclamation method on the basis of integrated use of magnetic resin adsorption and electrosorption is provided. It belongs to the water reclamation field, including the following steps: pump the biotreated effluent into a reactor that is filled with magnetic resin particles so that the chromaticity, organic pollutants, total nitrogen, total phosphorus contained in the wastewater can be effectively reduced; channel the fully reacted mixture into a precipitation tank for separation; part of the separated magnetic resin is pumped back into the reactor while the rest of the separated magnetic resin flows into a regeneration tank; the wastewater treated by magnetic resin adsorption then flows into an electrosorption unit for a desalting process; the remaining organic pollutants and inorganic pollutants are further removed.


Patent
Nanjing University of Technology | Date: 2016-11-30

It relates to the field of synthetic macromolecular chemistry, and discloses a method for one-step synthesis of thiol-functionalized polyester polyols by organic catalysis. This method uses lactone monomer as reaction raw material, thiol-alcohol as initiator, and diphenyl phosphate as organic catalyst to catalyze and synthesize the thiol-functionalized polyester polyols. The present invention provides a method which is simple, inexpensive, easily controllable and environmentally friendly to prepare thiol-functionalized polyester polyols with the easily available and controllable catalyst. The method can selectively catalyze the ring opening polymerization of lactone to prepare thiol-functionalized polyester polyols using the organic catalyst.


Patent
Nanjing University of Technology | Date: 2016-11-30

A method for preparing polyesteramides by organocatalysis. The polyesteramides are prepared by a ring-opening polymerization reaction of comonomer under the action of an activator and an initiator, with -caprolactone and -caprolactam taken as the comonomer, and an I type carbene carboxylate compound or an L type carbene carboxylate compound taken as catalysts.


Patent
Nanjing University of Technology | Date: 2016-01-13

A portable rapid detection device for heavy metal ions includes a card electrode and a thin-layer flow cell, wherein a three-electrode system of the card electrode is inserted in a micro-channel of the thin-layer flow cell; and heavy metal ions are detected by using an anodic stripping voltammetry (ASV), a solution to be detected flows by the surface of a working electrode in the micro-channel, and heavy metals are enriched and stripped on the surface thereof.


A method to prepare functional polyester polyols by using micro-reaction device, wherein mixing -caprolactone/-valerolactone monomer with mercapto alcohol evenly with appropriate organic solution under moistureless conditions, and continuously transferring the prepared mixing solution into a micro-reaction device supported with an immobilized enzyme for polymerization to synthetize a poly (-caprolactone/-valerolactone). Compared with the prior art, the present invention achieves a continuous production by using immobilized lipase Novozyme435 as a catalyst.


Mo M.,Nanjing University of Technology | Zhao L.,Nanjing University of Technology
Chemical Engineering Transactions | Year: 2016

Because the water quality in the central air conditioning cooling water circulation system exists a lot of sediment, widely breeding of microorganism and equipment corrosion problems, Serious damage to people's health and affect the service life of the air conditioning itself. In this paper, the use of high voltage pulsed discharge in water to produce a high-density non-thermal plasma bonding of the catalyst method to solve the problem, the paper introduces the technology of non-thermal plasma and catalyst separate disinfection sterilization mechanism and the mechanism of synergy respectively, the reactor configuration, and points out the research direction in the future. Copyright © 2016, AIDIC Servizi S.r.l.


Ji Y.,Nanjing University of Technology | Wang H.,Nanjing University of Technology | Zhang H.,Nanjing University of Technology
Materials Research Bulletin | Year: 2017

Gd0.8Sr0.2CoO3-δ–x Sm0.1Ce0.9O1.95 (GSC-x, x = 0–50 wt.%) composite cathodes were prepared by Glycine-Nitrate Process followed by mixing GSC and SDC powder. The thermal stability and electrical conductivity of GSC-x composite cathodes have been investigated for the application in intermediate temperature solid oxide fuel cells (IT-SOFCs). The thermal expansion coefficient of GSC-x decreased with the addition of SDC. The electrical conductivities of GSC-x cathode with 0–30 wt.% SDC were passed the line of 100 S cm−1. Especially for GSC-20, the conductivity of GSC-20 is more than 300 S cm−1 in temperature range of 600–750 °C. The area specific resistance (ASR) of GSC-20 was only 0.080 Ω cm2 at 750 °C, much lower than that of GSC cathode (ASR = 0.119 Ω cm2). The thermal expansion coefficient of GSC-20 decreased to 80% TEC of GSC cathode. © 2016


Qin X.,National University of Singapore | Liu X.,National University of Singapore | Huang W.,Nanjing University of Technology | Huang W.,Nanjing University of Posts and Telecommunications | And 2 more authors.
Chemical Reviews | Year: 2017

The synthesis of lanthanide-activated phosphors is pertinent to many emerging applications, ranging from high-resolution luminescence imaging to next-generation volumetric full-color display. In particular, the optical processes governed by the 4f-5d transitions of divalent and trivalent lanthanides have been the key to enabling precisely tuned color emission. The fundamental importance of lanthanide-activated phosphors for the physical and biomedical sciences has led to rapid development of novel synthetic methodologies and relevant tools that allow for probing the dynamics of energy transfer processes. Here, we review recent progress in developing methods for preparing lanthanide-activated phosphors, especially those featuring 4f-5d optical transitions. Particular attention will be devoted to two widely studied dopants, Ce3+ and Eu2+. The nature of the 4f-5d transition is examined by combining phenomenological theories with quantum mechanical calculations. An emphasis is placed on the correlation of host crystal structures with the 5d-4f luminescence characteristics of lanthanides, including quantum yield, emission color, decay rate, and thermal quenching behavior. Several parameters, namely Debye temperature and dielectric constant of the host crystal, geometrical structure of coordination polyhedron around the luminescent center, and the accurate energies of 4f and 5d levels, as well as the position of 4f and 5d levels relative to the valence and conduction bands of the hosts, are addressed as basic criteria for high-throughput computational design of lanthanide-activated phosphors. © 2017 American Chemical Society.


Yin K.,Nanjing University of Technology | Jiang J.,Nanjing University of Technology
International Journal of Safety and Security Engineering | Year: 2014

The Internet of Things (IoT) has become an important part in day-to-day activities, and it has become one of the important methods used in the development of information network technology. In this paper, the IoT technology is applied in buildings that are on fire to create a dynamic model of analysis based on relevant location algorithm. Compared with the traditional models of fire control systems, it has been found that the IoT-based models have at least three advantages: (1) can make a more timely collection of information; (2) can analyze information dynamically; and (3) can provide the best rescue plan, which is useful to establish an information fire control system. The application of this system can reduce the loss of property and the risk of personnel danger, providing an important reference for the construction of information system for fire protection and scientific management. © 2014 WIT Press.


Li Y.,Nanjing University of Technology
Journal of Computational and Theoretical Nanoscience | Year: 2016

In order to solve the problem of multi-objective optimization in green design, one solution and decision model integrating neural network and ant colony optimization (ACO) is proposed. This model takes the mechanical property, process performance, economic property, life cycle and environmental property of the material as the optimization objective, utilizes artificial neural network to conduct system modeling, finds the fitness function and method to seek the objective function value and then uses ACO to make multi-objective optimization. Ecological index approach is adopted to analyze quantitatively the influence of material on the environment within its life cycle. The selection of shell material for certain washing machine is taken as example, proving that this multi-objective decision model plays an important instructive role in material selection in green design. Copyright © 2016 American Scientific Publishers All rights reserved.


Huang H.,University of Nevada, Las Vegas | Huang H.,Nanjing University of Technology | Kang J.Y.,University of Nevada, Las Vegas
Organic Letters | Year: 2017

An efficient oxidation-reduction condensation reaction of diazaphosphites with various nonacidic pronucleophiles in the presence of DIAD as a weak oxidant has been developed for carbon-heteroatom bond formation. This mild process affords structurally diverse tertiary amines, secondary amines, esters, ethers, and thioethers in moderate to excellent yields. The selective synthesis of secondary amines from primary amines has been achieved. Importantly, a practical application to the synthesis of antiparkinsonian agent piribedil has been demonstrated. © 2017 American Chemical Society.


Wang C.-Q.,Nanjing University of Technology | Ye L.,Nanjing University of Technology | Feng C.,Nanjing University of Technology | Loh T.-P.,Anhui University of Science and Technology | Loh T.-P.,Nanyang Technological University
Journal of the American Chemical Society | Year: 2017

Using α,α-difluoromethylene alkyne as a nontraditional one-carbon reaction partner, a synthetically novel method for the construction of isoindolin-1-one derivatives via Rh(III)-catalyzed [4+1] annulation reaction is reported. The 2-fold C-F bond cleavage not only enables the generation of desired product under an overall oxidant-free condition but also results in a net migration of carbon-carbon triple bond. In addition, the present reaction protocol exhibits a tolerance of a wide spectrum of functional groups due to the mild reaction conditions employed. © 2017 American Chemical Society.


Han H.,Nanjing University of Technology | Zhou D.,Huaiyin Institute of Technology | Ji T.,University of Manchester
International Journal of Applied Mechanics | Year: 2017

In this paper, the dynamic interaction of human body and structure is studied The shaking table experiment with a person standing on a rigid table supported by springs is firstly carried out to determine the dynamic characteristics of the coupled system. It is shown that the body mainly contributes only one degree of freedom to the human-structure coupled system. Then, the two-degree-of-freedom (TDOF) coupled model of the human-structure system is developed through the energy variation by considering the standing human body as an elastic bar of two segments with distributed mass, stiffness and damping. Based on the experiment data, the dynamic parameters of the TDOF coupled system are determined by using the least square method (LSM). The mechanical parameters such as the damping ratio and the distributions of mass and stiffness of the human body model of two segments are identified by adopting the inversing technique Finally, the determined body model is applied to analyze the free vibration of beams and plates occupied by standing persons. The governing differential equations of the human-beam system and the human-plate system are, respectively, derived out. The dynamic characteristics of the human-structure interaction are obtained by the use of the complex mode theory. The results are compared with the experimental ones and those from the finite element simulations. Good agreement is observed for all cases. © 2017 World Scientific Publishing Europe Ltd.


Zhu J.,Nanjing University of Technology | Zhang G.,Nanjing University of Technology | Liu G.,Nanjing University of Technology | Liu Z.,Nanjing University of Technology | And 2 more authors.
Advanced Materials | Year: 2017

The practical applications of perovskite hollow fibers (HFs) are limited by challenges in producing these easily, cheaply, and reliably. Here, a one-step thermal processing approach is reported for the efficient production of high performance perovskite HFs, with precise control over their cation stoichiometry. In contrast to traditional production methods, this approach directly uses earth-abundant raw chemicals in a single thermal process. This approach can control cation stoichiometry by avoiding interactions between the perovskites and polar solvents/nonsolvents, optimizes sintering, and results in high performance HFs. Furthermore, this method saves much time and energy (≈ 50%), therefore pollutant emissions are greatly reduced. One successful example is Ba0.5Sr0.5Co0.8Fe0.2O3-δ HFs, which are used in an oxygen-permeable membrane. This exhibits high oxygen permeation flux values that exceed desired commercial targets and compares favorably with previously reported oxygen-permeable membranes. Studies on other perovskites have produced similarly successful results. Overall, this approach could lead to energy efficient, solid-state devices for industrial application in energy and environmental fields. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Jin Q.,Nanjing University of Technology | Shen Y.,Nanjing University of Technology | Zhu S.,Nanjing University of Technology
Journal of Colloid and Interface Science | Year: 2017

A series of CeO2(ZrO2)/TiO2 catalysts with fluorine additive were prepared by impregnation method and tested for selective catalytic reduction (SCR) of NO by NH3. These samples were characterized by XRD, N2-BET, Raman spectra, SEM, TEM, NH3-TPD, H2-TPR and XPS, respectively. Results showed that the optimal catalyst with the appropriate HF exhibited excellent performance for NH3-SCR and more than 96% NO conversion at 360 °C under GHSV of 71,400 h−1. It was found that the grain size of TiO2 increased and the specific surface area reduced with the modulation of HF, which was not good for the adsorption of gas molecule. However, the modulation of HF exposed the high energy (0 0 1) facets of TiO2 and increased the surface chemisorbed oxygen concentration, oxygen storage capacity and Ce3+ concentration of catalyst. In addition, the synergy of (1 0 1) and (0 0 1) facets was beneficial to the improvement of catalytic activity. © 2016 Elsevier Inc.


Yu Q.,Nanjing University of Technology | Jiang J.C.,Nanjing University of Technology
Petroleum Science and Technology | Year: 2017

In this study, the authors used a specially designed experimental device to detect the amount of diesel that evaporated at different diesel and environmental temperatures and quantify the distribution of diesel at different heights within the subsequent vapor cloud. They also examined the relationship between the total diesel concentration of the vapor cloud and the amount of diesel evaporated, the relationship between the explosive threshold of the diesel vapor cloud and the environmental temperature, and the formation of the vapor cloud. Finally, the authors investigated the conditions relevant to the formation of an explosive vapor cloud after diesel spillage. © 2017 Taylor & Francis Group, LLC.


Wang L.,Nanjing University of Technology | Niu C.,Shenyang Aerospace University | Li R.-D.,Shenyang Aerospace University
Waste and Biomass Valorization | Year: 2017

Municipal solid waste incinerator (MSWI) fly ash contains large amounts of arsenic and antimony. This study focuses on the incorporation and evaporation of arsenic and antimony when MSWI fly ash added to clinker raw meal. Thermal analysis was used to simulate the “single incorporation” of arsenic and antimony into clinker with HSC. Statistical analysis was acquired by cement industrial monitoring data to determine the effect of total chloride, arsenic and antimony input on the incorporation or evaporation of arsenic or antimony. A simplified mass balance model was used to evaluate the effect of cement kiln dust (CKD) recirculation on the “multiple incorporation” of arsenic and antimony in clinker and the evaporation of arsenic and antimony in waste CKD. The results indicated that arsenic and antimony was largely incorporated into the clinker as Ca2(AsO4)2(s), even in the presence of chlorides. Moreover, CKD recirculation promoted arsenic and antimony incorporation into clinker. © 2017 Springer Science+Business Media Dordrecht


Zhang B.,Nanjing University of Technology | Yu X.,Nanjing University of Technology | Gu B.,Nanjing University of Technology
Polymer Composites | Year: 2017

This article presents an experimental and numerical study on mechanical behavior of sepiolite reinforced rubber sealing composites (SRRC), which are subjected to the transverse tensile loads. A finite element model of composites with fibers in square and random distribution is adopted for the numerical study. The representative volume elements with different fiber volume fraction are established and analyzed. A successive remeshing strategy is employed to achieve the large deformation of SRRC. The results show that the tensile strength and breaking elongation of SRRC can be improved by addition of sepiolite fiber, and they reach a maximum at 42% fiber volume fraction. The stress-strain curve of SRRC with fibers in the random distribution agrees well with that measured in the experiments. However, there exists a significant difference between experimental and numerical results as fiber volume fraction increases. POLYM. COMPOS., 38:381–388, 2017. © 2015 Society of Plastics Engineers. © 2015 Society of Plastics Engineers


Li M.,University of Queensland | Zhou W.,Nanjing University of Technology | Zhu Z.,University of Queensland
ACS Applied Materials and Interfaces | Year: 2017

(Graph Presented) Susceptibility to CO2 is one of the major challenges for the long-term stability of the alkaline-earth-containing cathodes for intermediate-temperature solid oxide fuel cells. To alleviate the adverse effects from CO2, we incorporated samarium-stabilized ceria (SDC) into a SrCo0.85Ta0.15O3-δ (SCT15) cathode by either mechanical mixing or a wet impregnation method and evaluated their cathode performance stability in the presence of a gas mixture of 10% CO2, 21% O2, and 69% N2. We observed that the CO2 tolerance of the hybrid cathode outperforms the pure SCT15 cathode by over 5 times at 550°C. This significant enhancement is likely attributable to the low CO2 adsorption and reactivity of the SDC protective layer, which are demonstrated through thermogravimetric analysis, energy-dispersive spectroscopy, and electrical conductivity study. © 2017 American Chemical Society.


Su J.,Nanjing University of Technology | Su J.,Nanjing Institute of Industry Technology | Zhang J.,Nanjing University of Technology
Journal of Applied Polymer Science | Year: 2017

In this study, mica, treated by three types of coupling agents, isopropyl trioleic titanate (NDZ105), 3-aminopropyltriethoxysilane (KH550), and vinyltrimethoxysiloxane homopolymer (SG-Si6490), were utilized to improve the properties of ethylene propylene diene monomer (EPDM)/barium titanate (BaTiO3) composites. It is found that the addition of untreated mica can increase the complex viscosity, while the KH550 modified mica can reduce the complex viscosity. Compared to single usage of coupling agent SG-Si6490, the hybrid usage of KH550 and SG-Si6490 can further increase the tensile strength of EPDM/BaTiO3/SG-Si6490 treated mica (70/20/10) from 9.10 to 11.01 MPa (22% increase). The untreated mica can increase the interfacial polarity and improve the dielectric constant of EPDM/BaTiO3 (70/30) from 7 to 9 at 40 MHz (28% increase). Moreover, the KH550 treated mica can enhance the thermal conductivity of EPDM/BaTiO3 (70/30) from 0.323 W m−1 K−1 to 0.446 W m−1 K−1 (38% increase). In the meantime, the increased crosslink density caused by coupling agents can increase the volume resistivity of EPDM composites. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44833. © 2017 Wiley Periodicals, Inc.


Zhang S.,University of Pennsylvania | Kim B.-S.,University of Pennsylvania | Wu C.,Nanjing University of Technology | Mao J.,University of Pennsylvania | And 2 more authors.
Nature Communications | Year: 2017

Tetraarylmethane derivatives are desirable for a variety of applications, but difficult to access with modern C-C bond-forming reactions. Here we report a straightforward method for palladium-catalysed arylation of aryl(heteroaryl)methanes and diaryl(heteroaryl)methanes with aryl chlorides. This reaction enables introduction of various aryl groups to construct triaryl(heteroaryl)methanes via a C-H functionalization in good to excellent yield, and represents the first step towards a general transition metal catalysed synthesis of tetraarylmethanes. © The Author(s) 2017.


Shan B.,Hunan University | Xiao Y.,Nanjing University of Technology | Zhang W.L.,Jiangsu Transportation Research Institute | Liu B.,Hunan University
Construction and Building Materials | Year: 2017

This paper reports testing results of various connections for composite beams made of concrete slab and glue-laminated bamboo (glubam) beam. Six types of composite connectors, commonly used in timber-concrete composite (TCC) beams, were tested under direct shear condition. The shear force-slip relationships were measured and all the relevant mechanical properties such as slip moduli and shear capacities were obtained. Compared with typical TCC beam connections, the Glubam-concrete composite (BCC) systems present several different characteristics. The shear failure along the notch, typical in TCC notched connectors was not observed for BCC system, however, the delamination cracking along the lamination layers occurred in some types of BCC connections. Based on the test results and analysis, six types of connectors can be classified into two categories, one with higher strength and stiffness but low ductility, and the other with lower strength and stiffness but higher ductility. A set of regression equation with a bilinear descent segment is also provided for simulating the shear-slip behaviors of each type connector. It is found that some of the connection systems including the notched connector, steel mesh connector, screw connector and pre-tightening notched connector, are more suitable and recommended for constructing BCC structures. © 2017


Chen Y.,Xiamen University | Wang Y.,Nanjing University of Technology | Peng J.,Xiamen University | Xu Q.,Xiamen University | And 2 more authors.
ACS Nano | Year: 2017

Ultrathin nanowires (NWs) are considered to be ideal building blocks for the assembly of complex nanostructures toward future nanodevices. The polymer/particle duality of ultrathin NWs plays an important role in the study of solution phase self-assembly behavior of ultrathin NWs; yet it has not been fully exploited. Herein, we demonstrate the effects of the polymer/particle duality of ultrathin NWs on the morphologies of assembled complex nanostructures. The length of ultrathin AuNWs directly correlates with the flexibility of NWs and affects the polymer-like assembly of NWs, while the concentration of surfactants determines interfacial tension and ligand-solvent interactions and affects both polymer-like and colloidal assembly of NWs. By fine-tuning these two factors, ultrathin AuNWs can swing between "soft" and "hard" building blocks, and highly uniform nanorings, nanograins, nanobundles, and superlattice-like nanospheres are obtained. The different assembly behavior of long and short NWs can be considered as two components to construct anisotropic complex nanostructures, in analogy with the fabrication of polymer-inorganic nanoparticle hybrid nanostructures. We synthesized anisotropic structures of Au nanodiamond rings and nanonecklaces by the coassembly of polymer-like long NWs with particle-like short NWs or Au nanoparticles. This strategy could potentially be extended to the organization of anisotropic complex nanostructures with other ultrathin NW systems in the future. © 2017 American Chemical Society.


Huang H.,Chongqing University | Shen X.-D.,Nanjing University of Technology
Advances in Cement Research | Year: 2017

The effectiveness of 15 chemical admixtures (including alkanolamines, alcohols, chloride/non-corrosive accelerators and retarders) on the early strength development of a P.II 52.5R cement was determined using statistical methods. The results showed that, under low dose conditions (≤ 0.05 wt%), sodium thiocyanate, calcium chloride, sodium hydroxide, triethanolamine and glucose contributed to the 1-d strength enhancement of the cement and that only sodium thiocyanate, triethanolamine, triisopropanolamine and calcium chloride were effective up to 3 d. In addition to the strength test proposed by the statistical model, a calorimeter was used for a supplementary measurement to identify interactions among the chemicals. The calorimetric test results revealed that the interaction between triethanolamine and sodium thiocyanate was more pronounced for the amount of heat released before 72 h due to the accelerating effects on both the C3S and C3A phases. Furthermore, a statistical test showed that even at a higher dose (0.1 wt%), the effect of calcium nitrate was far less efficient than the effect of calcium chloride, which did not significantly improve the overall early strength of cement. © 2017, ICE Publishing. All rights reserved.


Zhang C.,Nanjing University of Technology | Li L.,Nanjing University of Technology | Wang X.,Nanjing University of Technology | Xue G.,Nanjing University of Technology
Macromolecules | Year: 2017

The glass transition behaviors of poly(methyl methacrylate) (PMMA) nanofibers confined in pristine and surface-modified AAO templates are investigated by differential scanning calorimetry (DSC) and broadband dielectric spectroscopy (BDS). During an ultraslow cooling process (0.1 K/min) across the Tg, two glass transition temperatures (Tg,low and Tg,high) are clearly identified by DSC and BDS, which correspond to the core and shell, respectively. The Tg,high originates from the transition of the adsorbed layer and is mainly dominated by the geometric curvature radius of the nanopores rather than the chemical nature of the wall surface. A dramatic change in the glass transition behaviors is detected when the cooling rate is changed from 40 to 0.1 K/min, which reflects the inherent evolution between the shell and the core through a nonequilibrium interlayer. Furthermore, by studying the system before and after surface modification of the nanopores by silanization, we suggest that such evolution could be sped up through the benefit of the stronger interfacial interactions. Our findings provide insight into achieving stable glassy polymer structures confined in nanopores by balancing the geometric curvature, interfacial interactions, and cooling rate. © 2017 American Chemical Society.


Chen X.,Nanjing University of Technology | Han X.,Nanjing University of Technology | Shen Q.-D.,Nanjing University of Technology
Advanced Electronic Materials | Year: 2017

Ferroelectric polymers are the most promising electroactive materials with outstanding properties that can be integrated into a variety of flexible electronic devices. Their multifunctional capabilities, ability to bend and stretch, ease of processing, chemical stability, and the high biocompatibility of polyvinylidene fluoride (PVDF)-based polymers make them attractive for applications in flexible memories, energy transducers, and electronic skins. Here, recent advance in the research of PVDF-based flexible electronic devices is reviewed, including nonvolatile memories, energy-harvesting devices, and multifunctional portable sensors. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Kou J.,Nanjing University of Technology | Lu C.,Nanjing University of Technology | Wang J.,Nanjing University of Technology | Chen Y.,Nanjing University of Technology | And 2 more authors.
Chemical Reviews | Year: 2017

Photocatalysis has been invariably considered as an unselective process (especially in water) for a fairly long period of time, and the investigation on selective photocatalysis has been largely neglected. In recent years, the field of selective photocatalysis is developing rapidly and now extended to several newer applications. This review focuses on the overall strategies which can improve the selectivity of photocatalysis encompassing a wide variety of photocatalysts, and modifications thereof, as well as the related vital processes of industrial significance such as reduction and oxidation of organics, inorganics, and CO2 transformation. Comprehensive and successful strategies for enhancing the selectivity in photocatalysis are abridged to reinvigorate and stimulate future investigations. In addition, nonsemiconductor type photocatalysts, such as Ti-Si molecular sieves and carbon quantum dots (CQDs), are also briefly appraised in view of their special role in special selective photocatalysis, namely epoxidation reactions, among others. In the end, a summary and outlook on the challenges and future directions in the research field are included in the comprehensive review. © 2017 American Chemical Society.


Zhao K.,Nanjing University of Technology | Zhao K.,Nanyang Technological University | Shen L.,Nanyang Technological University | Shen Z.-L.,Nanjing University of Technology | And 3 more authors.
Chemical Society Reviews | Year: 2017

Transition metal-catalyzed cross-coupling reactions using organoindium reagents have witnessed rapid and comprehensive development in the past two decades. In comparison with many other organometallic reagents, the preparation of organoindium reagents and the subsequent transition metal-catalyzed cross-coupling reactions with various electrophiles showed a wider tolerance to important functional groups and protic solvents. In addition, in many cases, cross-coupling reactions employing organoindium reagents exhibited remarkable chemo- and stereoselectivity. In this tutorial review, we summarize and highlight the most important developments in this rapidly advancing area, with special emphasis on their utilities in organic synthesis and materials science. © 2017 The Royal Society of Chemistry.


Yuan Y.-J.,Nanjing University of Technology | Yuan Y.-J.,Hangzhou Dianzi University | Yu Z.-T.,Nanjing University of Technology | Chen D.-Q.,Hangzhou Dianzi University | Zou Z.-G.,Nanjing University of Technology
Chemical Society Reviews | Year: 2017

Solar H2 generation from water has been intensively investigated as a clean method to convert solar energy into hydrogen fuel. During the past few decades, many studies have demonstrated that metal complexes can act as efficient photoactive materials for photocatalytic H2 production. Here, we review the recent progress in the application of metal-complex chromophores to solar-to-H2 conversion, including metal-complex photosensitizers and supramolecular photocatalysts. A brief overview of the fundamental principles of photocatalytic H2 production is given. Then, different metal-complex photosensitizers and supramolecular photocatalysts are introduced in detail, and the most important factors that strictly determine their photocatalytic performance are also discussed. Finally, we illustrate some challenges and opportunities for future research in this promising area. © 2017 The Royal Society of Chemistry.


Zhu S.,Nanjing University of Technology | Zhang J.,Nanjing University of Technology
Iranian Polymer Journal (English Edition) | Year: 2017

Acrylonitrile–butadiene rubber (NBR), a synthetic rubber having C≡N dipoles, was chosen as a polymer matrix with a higher dielectric constant than other non-polar rubber like silicone rubber or ethylene–propylene–diene monomer. Barium titanate (BaTiO3), as a ferroelectric material, with a high dielectric constant and low dielectric loss was selected as a main filler to further enhance the dielectric constant of NBR. An effective silane coupling agent (KH845-4), selected from five types of silane coupling agents with different characteristic functional groups, was used to modify the surface of BaTiO3 particles to enhance its interfacial adhesion to the matrix. Fourier transform infrared spectroscopy (FTIR) was used to verify the successful modification. The addition of BaTiO3 obviously enhanced the dielectric constants. In particular, an uncommon pattern of dielectric loss has been displayed and analyzed in this paper. Nevertheless, the reinforcing effect of mechanical strength of the NBR/treated BaTiO3 composites is limited. On this basis, the addition of nanosilica (SiO2), replacing part of NBR, improved the mechanical strength. Confirmed by scanning electron microscopy (SEM), the SiO2 and treated BaTiO3 particles were dispersed well in the NBR matrix. The tensile strength was increased from 4.33 to 6.12 MPa when SiO2 accounted for 4%. Moreover, the curing characterizations, crosslinking density, resistivity, and oil resistance were evaluated. This composite material can be used in manufacturing electronic devices, which are subjected to oily environments for a long time. © 2017, Iran Polymer and Petrochemical Institute.


Du Y.,Nanjing University of Technology | Fang J.,Nanjing University of Technology | Wang H.,Nanjing University of Technology | Yang Y.,Nanjing University of Technology
ACS Applied Materials and Interfaces | Year: 2017

Direct and fast detection methods for H2O2 have great demand in materials science, biology, and medicine. Colorimetric assay of H2O2 has been regarded as one versatile approach that can avoid tedious operation and complicated setup. In this report, we provided a cost-effective and time-saving H2O2 colorimetric assay strategy based on a mercaptosuccinic acid (MSA)-stabilized Cu nanocluster (NC) probe without using any chromogenic reagent. Direct and fast colorimetric detection of H2O2 was realized based on the color change of MSA-capped Cu NCs in aqueous medium. It was found that the Cu NCs presented eligible resistance to natural oxidation either in concentrated solution or in the powder state. However, the dissolved oxygen in a highly diluted solution of the Cu NCs could trigger the aggregation of the Cu NCs and their further fusion into small Cu nanoparticles (NPs). When this diluted solution served as a probe solution for detecting H2O2, a sequential oxidation process occurred in the newly formed Cu NPs, including the cleavage of MSAs on the surface and conversion of Cu into Cu2O, leading to the probe with capacity for H2O2 assay in a wide dynamic and sampling range. The sensitive solution color change was attributed to the growth of the Cu NPs (fading of plasmonic absorption) upon the addition of low levels of H2O2 and the transition of the valence states of Cu (color reactions) upon the addition of high levels of H2O2. A concentration range of H2O2 from 1 μM to 1 M could be detected by a small dose of the probe. Moreover, the Cu NCs powder subsequent to storage for 10 months could maintain a similar sensitivity for H2O2 assay, which provides possibilities for a wide range of practical applications in water samples. © 2017 American Chemical Society.


Cai X.,Nanjing University of Technology | Zhu H.,Nanjing University of Technology | Zhang Y.,Nanjing University of Technology | Gu Z.,Nanjing University of Technology
ACS Applied Materials and Interfaces | Year: 2017

RNA interference (RNAi) has a great promise in treating various acquired and hereditary diseases. However, it remains highly desirable to develop new delivery system to circumvent complex extra- and intracellular barriers for successful clinical translation. Here, we report on a versatile polymeric vector, bioreducible fluorinated peptide dendrimers (BFPD), for efficient and safe small interfering RNA (siRNA) delivery. In virtue of skillfully integrating all of the unique advantages of reversible cross-linking, fluorination, and peptide dendrimers, this novel vector can surmount almost all extra- and intracellular barriers associated with local siRNA delivery through highly improved physiological stability and serum resistance, significantly increased intratumoral enrichment, cellular internalization, successful facilitation of endosomal escape, and cytosolic siRNA release. BFPD polyplexes, carrying small interfering vascular endothelial growth factor (siVEGF), demonstrated excellent VEGF silencing efficacy (∼65%) and a strong capability for inhibiting HeLa cell proliferation. More importantly, these polyplexes showed superior performance in long-term enrichment in the tumor sites and had a high level of tumor growth inhibition. Furthermore, these polyplexes not only exhibited excellent in vivo antitumor efficacy but also demonstrated superior biocompatibility, compared with LPF2000, both in vivo and in vitro. These findings indicate that BFPD is an efficient and safe siRNA delivery system and has remarkable potential for RNAi-based cancer treatment. © 2017 American Chemical Society.


Shao F.,Jiangnan University | Feng P.,Nanjing University of Technology | Wan C.,Nanjing University | Wan X.,Nanjing University | And 3 more authors.
Advanced Electronic Materials | Year: 2017

Paper electronics represents a newly raised concept that includes various types of electronic devices and circuits on paper. In this work, the authors report multigate oxide-based homojunction electric-double-layer thin-film transistors (TFTs) with cellulose nanofibers electrolyte film as the gate dielectrics on paper substrate. These flexible TFTs exhibit high performance with a high ON/OFF ratio of 107 and a high mobility of around 26 cm2 V-1 s-1. Resistor-loaded inverters are demonstrated both in a bottom-gate mode and an in-plane-gate mode. Logic AND operation is realized in a device with two in-plane gates. Significantly, the universal logic NAND is experimentally demonstrated using a one transistor/one resistor structure by combining NOT and AND logics together. The paper-based TFT devices are very interesting for emerging areas such as disposable paper electronics and sensors. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Li J.,Nanjing Forestry University | Ling X.,Nanjing University of Technology | Peng H.,Nanjing University of Technology
Experimental Thermal and Fluid Science | Year: 2017

The object of this work is to investigate the boiling heat transfer performance of transverse serrated fin (TSF) channel and triangle perforated fin (TPF) channel in compact plate-fin heat exchanger. A series of boiling heat transfer performance tests are carried out for volume flow rate range of 0.03–0.3 m3/h and heat flux of 10–20 kW/m2. The local and average heat transfer coefficient of TSF channel and TPF channel are examined. It indicates that both local and average boiling heat transfer coefficient of TSF channel was higher than that of TPF channel. The boiling heat transfer occurs in TSF channel at lower wall superheat. The growth rate of wall temperature significant declines significantly when heat flux is up to ONB point, which means the boiling heat transfer has happened. The rising rate of average boiling heat transfer coefficient have is smaller than that of the local boiling heat transfer coefficient hout. © 2017 Elsevier Inc.


Wang L.,Hong Kong Polytechnic University | Xiao F.,Hong Kong Polytechnic University | Niu X.,Nanjing University of Technology
Refrigeration Science and Technology | Year: 2015

This paper develops a liquid desiccant dehumidification experimental facility. Tests on the dynamic characteristics of the dehumidification process are conducted on the counter-flow structured packing dehumidifier. The time constant of the dynamic response is defined to characterize the dynamic processes. Experiments with different inlet conditions show that time constants of the outlet air humidity ratio and temperature are not always equal. The transient time can be up to 250 seconds before the outlet variables of air achieve steady state. The dynamic responses of the outlet humidity ratio and temperature to the step changes of the mass flow rate of solution are also tested. The experimental results and analysis can be used for modeling validation of liquid desiccant dehumidification processes.


Jin S.,Nanjing University of Technology | Bu G.,Nanjing University of Technology
Refrigeration Science and Technology | Year: 2015

The system of multistage tanks applied to the solar air conditioning was presented. Above the theoretical analyzing, the system of multistage tanks test-bed has been built to study the performance of the multistage tanks system with different series. The results showed that: the heat storage consuming time of the first-stage tank decreased and the heat storage grade improved with increasing the system series, and the time of ideal heating inlet water temperature increased with increasing the system series, in the heat release period, the conclusion is opposite. According to the above conclusion, the optimization strategy for the system of multistage tanks was proposed, the system after optimization has obvious effect prolonging the time of ideal heating inlet water temperature.


Niu X.,Nanjing University of Technology | Li X.,Nanjing University of Technology | Qiu W.,Nanjing University of Technology
Refrigeration Science and Technology | Year: 2015

In conventional liquid desiccant system, the diluted solution after dehumidification is usually completely sent to the regenerator, which leads to the poor system performance. This paper tries to study on the effect of the solution regeneration reflux ratio on the overall system. Firstly, the novel configuration of liquid desiccant system that can adjust the reflux ratio of regeneration was put forward. Then, the major components of the system were modelled mathematically. Lastly, energy consumption and the system coefficient of performance (COP) under different conditions, including different moisture-removing load and varied solution regeneration reflux ratio, were simulated. The results show that, the overall performance of the liquid desiccant system can be improved by reducing the solution regeneration reflux ratio, moreover, the improving effect are stronger under lower solution regeneration temperature and lower moisture-removing load. However, the reflux ratio cannot be reduced unlimited since the regeneration temperature will be higher, thus there is a rational optimal solution regeneration reflux ratio.


Xinghua Z.,Nanjing University of Technology | Pengfei C.,Nanjing University of Technology
19th International Conference on Electrical Machines and Systems, ICEMS 2016 | Year: 2016

An efficiency optimization control strategy of the direct torque controlled interior permanent magnet synchronous motors is proposed. Firstly, the mathematical model of the IPMSM is established in the rotor frame considering iron losses. Secondly, the function relationship between the power losses and the output torque, speed and stator flux is analyzed, and the computational formula of the stator flux amplitude which makes the power losses minimization is derived under different operating conditions. Consequently, the efficiency optimization control for direct torque controlled IPMSM driving systems is achieved. The experimental results show that the proposed control method not only preserves the fast torque dynamic response of the conventional direct torque control, but also improves operating efficiency of the driving system. © 2016 The Institute of Electrical Engineers of Japan.


Gao W.C.,Nanjing University of Technology | Gao W.C.,Hunan University | Xiao Y.,Nanjing University of Technology | Xiao Y.,Hunan University
Journal of Constructional Steel Research | Year: 2017

This paper presents an experimental study on the monotonic and cyclic lateral loading behavior of cold-formed steel (CFS) shear walls sheathed with glued laminated bamboo (glubam ply-bamboo) panels. A total of 16 model shear wall specimens with two types of aspect ratios were tested using ASTM loading protocols. The observed phenomena and the effects of different cyclic loading regimes are discussed. The shear capacity and deformability of ply-bamboo sheathed CFS shear walls are evaluated and compared with wood sheathing panel (WSP) sheathed CFS shear walls through four seismic equivalency parameters recommended by American Iron and Steel Institute (AISI) in 2010 (AISI-RP10-4 2010). The load distribution of the screws along the vertical edges of the panels and the forces in the shear anchors are discussed. The results obtained in this study can further promote the application of bamboo-based material in CFS structures, as potential options for eco-friendly and cost-effective construction. © 2017 Elsevier Ltd


Liu T.,Hunan University | Xiao Y.,Nanjing University of Technology | Yang J.,Hong Kong Huayi Design Consultants Shenzhen Ltd. | Chen B.S.,Hunan University
Journal of Composites for Construction | Year: 2017

A half-scale, three-story, two-bay, and three-span reinforced concrete model frame retrofitted with carbon fiber-reinforced polymer (CFRP) strip cables was tested under sudden removal of two side middle columns in the long direction on the ground floor to study dynamic responses, resisting mechanism, and CFRP retrofit effects. The CFRP strip cables were anchored to concrete slabs by specially designed anchorage. The experimental results are compared with previous tests of the same frame without CFRP retrofit. The comparison shows that the CFRP strip cables were effective in preventing the total collapse of the frame after the loss of columns. With additional CFRP strip cables, the frame structure sustained the applied gravity load as moment-resisting frames without a transition to catenary action. To further demonstrate the effects, the CFRP strip cables were released, causing the frame structure to deflect downward and eventually collapse. A simplified method was proposed to calculate the average strain on CFRP strip cables and a combining resisting mechanism was established to compute the ultimate capacity provided by slabs, beams, and CFRP strip cables. © 2016 American Society of Civil Engineers.


Shi X.,Nanjing University of Technology | Wang Z.,Nanjing University of Technology | Wang Y.,Nanjing University of Technology
Journal of Membrane Science | Year: 2017

Block copolymer (BCP) membranes are distinguished for their well-defined porosities, tunable pore geometries, and functionable pore walls. However, it remains challenging to produce robust BCP membranes by affordable, convenient methods. Herein, we demonstrate a facile and easily upscalable approach to produce highly permeable BCP membranes in large areas. The membranes possess a bi-layered composite structure with nanoporous polystyrene-block-poly(2-vinylpyrdine) BCP layers directly supported on macroporous nonwoven substrates. The BCP layers are machine-cast on the water-prefilled nonwoven, and interconnected nanoporosities are created in the BCP layers by ethanol swelling. The nanoporous BCP layers exhibit a thickness of ~10 µm and are tightly adhered to the nonwoven. Changes in the swelling temperatures and durations modulate both pore sizes and surface hydrophilicity of the BCP layers, and consequently the permselectivity of the membranes. By increasing swelling duration from 15 min to 12 h, the permeability of the membrane swollen at 65 °C can be increased from ~100 to ~850 L m−2 h−1 bar−1 with the retention to 15-nm gold nanoparticles reduced from ~93% to ~54%. Moreover, we demonstrate that the composite membrane can efficiently fractionate nanoparticles and narrow down their size distribution from ~3–20 nm to ~3–10 nm. © 2017 Elsevier B.V.


Lan Q.,Nanjing University of Technology | Yan N.,Nanjing University of Technology | Wang Y.,Nanjing University of Technology
Journal of Membrane Science | Year: 2017

Mesoporous polymers derived from supramolecules of phenolic resins (PRs) and block copolymers (BCPs) containing highly uniform pores with sizes down to a few nanometers, are expected to deliver promising membrane separation performances. Here we report on the preparation of mesoporous phenolic membranes exhibiting tight ultrafiltration properties through a pore-filling strategy. Solutions of PR/BCP supramolecules are filled into the macropores of polyvinylidene fluoride (PVDF) microfiltration membranes (substrates), followed by thermopolymerization to solidify the solution in the pores. Subsequently, the filled PVDF substrates are treated in hot H2SO4 to remove the BCP components, thus producing mesopores in the PR framework. The produced composite membranes are mechanical robust and ductile as mesoporous phenolic resins are tightly embedded in the pores of the PVDF matrix. The mesoscale porosity in the PR phases endow the composite membrane a tight ultrafiltration performance with the molecular-weight-cut-off (MWCO) down to 2350 Da. The separation properties can be tuned simply by adjusting the dosage of supramolecule solutions used to fill the macroporous substrates. Considering the tight and uniform pore sizes and the robustness of phenolic resins, this strategy opens a new avenue to ultrafiltration membranes with low MWCOs or even nanofiltration membranes. © 2017 Elsevier B.V.


Zhang B.,Changshu Institute of Technology | Yu X.,Changshu Institute of Technology | Gu B.,Nanjing University of Technology
Fibers and Polymers | Year: 2017

An improved micromechanical shear lag model, which considers the interphase and bonded fiber end, is developed to investigate the load-carrying characteristics and stress profiles in hybrid aramid/sepiolite fiber reinforced rubber composites. The properties of the equivalent matrix, which is combination of sepiolite fiber and rubber matrix, are determined by Mori-Tanaka method. The axial and shear stresses at the fiber end are resolved by the imaginary fiber technique. The results obtained from the improved model show the tensile stress has a maximal at the real fiber center and the interfacial shear stress has a maximal at the end of the real fiber. Comparing with the results from Tsai’s model, the improved model has a better agreement with the numerical simualtion results. The effects of the imaginary fiber length on the stress transfer are analyzed and the results show that the effects can be ignored when the imaginary fiber length is greater than twice of the fiber radius. The effects of interphase modulus and thickness on the maximal axial and shear stresses are discussed. The results show that the interphase modulus and thickness of about 106.3 MPa and 0.2 μm are optimal to prevent interfacial debonding and improve the strength of hybrid fiber reinforced rubber composites. © 2017, The Korean Fiber Society and Springer Science+Business Media Dordrecht.


Rui L.,Shanghai Key Laboratory of Advanced Polymeric Materials | Xue Y.,Shanghai Key Laboratory of Advanced Polymeric Materials | Wang Y.,Nanjing University of Technology | Gao Y.,Shanghai Key Laboratory of Advanced Polymeric Materials | Zhang W.,Shanghai Key Laboratory of Advanced Polymeric Materials
Chemical Communications | Year: 2017

A mitochondria-targeting supramolecular photosensitizer system TPP-QAS/WP5/DTAB was constructed based on a host-guest inclusion complex. The supramolecular system could efficiently release and activate TPP-QASs in an acidic environment, which have been demonstrated to preferentially accumulate in mitochondria. Singlet oxygen (1O2) could be in situ generated in mitochondria under light irradiation, further enhancing the PDT efficacy. © The Royal Society of Chemistry.


Zhu C.,Nanjing University of Technology | Feng C.,Nanjing University of Technology | Yamane M.,Nanyang Technological University
Chemical Communications | Year: 2017

An efficient synthesis of (3-isoindazolyl)allenes from 2-alkynyl azobenzenes and terminal alkynes via cooperative Pd(PPh3)2Cl2/CuI-catalyzed cross-coupling has been developed. By making use of this approach, (3-isoindazolyl)allenes with various substituents can be synthesized in good to excellent yields. A rapid synthesis of biologically active indazolo[2,3-a]quinoline was also achieved using this method as the key step. © The Royal Society of Chemistry.


Zhu Y.,Nanjing University of Technology | Zhou W.,Nanjing University of Technology | Shao Z.,Curtin University Australia
Small | Year: 2017

Oxygen electrocatalysis, i.e., oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), plays an extremely important role in oxygen-based renewable-energy technologies such as rechargeable metal-air batteries, regenerative fuel cells and water splitting. Perovskite oxides have recently attracted increasing interest and hold great promise as efficient ORR and OER catalysts to replace noble-metal-based catalysts, owing to their high intrinsic catalytic activity, abundant variety, low cost, and rich resources. The introduction of perovskite-carbon interfaces by forming perovskite/carbon composites may bring a synergistic effect between the two phases, thus benefiting the oxygen electrocatalysis. This review provides a comprehensive overview of recent advances in perovskite/carbon composites for oxygen electrocatalysis in alkaline media, aiming to provide insights into the key parameters that influence the ORR/OER performance of the composites, including the physical/chemical properties and morphologies of the perovskites, the multiple roles of carbon, the synthetic method and the synergistic effect. A special emphasis is placed on the origin of the synergistic effect associated with the interfacial interaction between the perovskite and the carbon phases for enhanced ORR/OER performance. Finally, the existing challenges and the future directions for the synthesis and development of more efficient oxygen catalysts based on perovskite/carbon composites are proposed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Shi J.-Q.,Nanjing University of Technology | Ma H.-F.,Nanjing University of Technology
Rengong Jingti Xuebao/Journal of Synthetic Crystals | Year: 2016

The paper gives a brief review of a new nanocrystalline morphology-Au nanostar. The main processes of the preparation of Au nanostars was introduced. The applications of Au nanostars were elaborated, including drug carrier and release, catalytic and SERS enhancements. At the same time, applications of some other noble metals nanostars were describes briefly. By adding different kinds of noble metal seeds, the reducing agent and surfactants and adjusting the molar ratio of [salt concentrations]/[number of seeds], the number of tips and its lengths can be changed to control. At last, the existing problems of nanostars and improvement measures are proposed. © 2016, Chinese Ceramic Society. All right reserved.


Chen C.C.,Nanjing University of Technology | Fan T.,Nanjing University of Technology
Journal of Materials Science: Materials in Electronics | Year: 2017

Carbon quantum dots/Bismuth ferrite (CQDs/BiFeO3) composite materials were successfully synthesized by a facile hydrothermal treatment of Fe(NO3)3·9H2O, Bi(NO3)3·5H2O and CQDs solutions. The structural and optical characteristics of the composite materials were characterized by X-ray diffraction, Fourier transform infra-red spectroscopy, transmission electron microscopy and ultraviolet–visible absorption, respectively. The photocatalytic activities of pure BiFeO3, CQDs and CQDs/BiFeO3 composite materials had also been carried out by using Rhodamine B as test stuff. The experimental results indicated that for QDs/BiFeO3 composite materials, the CQDs were attached to the surfaces of BiFeO3 materials, CQDs and BiFeO3 belong to different phase. Owing to the heterojunction formed at the interface between CQDs and BiFeO3 materials together with CQDs as an electron reservoir, the photocatalytic activities of CQDs/BiFeO3 composite materials were significantly improved. Especially, the CQDs/BiFeO3 composite sample with 3.3 wt% CQDs has the highest degradation rate, which was about 7.3, 3.7 times higher than those of pure BiFeO3 and CQDs, respectively. Moreover, the mechanism of RhB degradation catalyzed by CQDs/BiFeO3 composite materials was also thoroughly explained. © 2017 Springer Science+Business Media New York


Liu C.,Nanjing University | Wu X.,Qufu Normal University | Wu X.,Nanjing University of Technology
Journal of Computational Physics | Year: 2017

In this paper we explore arbitrarily high-order Lagrange collocation-type time-stepping schemes for effectively solving high-dimensional nonlinear Klein–Gordon equations with different boundary conditions. We begin with one-dimensional periodic boundary problems and first formulate an abstract ordinary differential equation (ODE) on a suitable infinity-dimensional function space based on the operator spectrum theory. We then introduce an operator-variation-of-constants formula which is essential for the derivation of our arbitrarily high-order Lagrange collocation-type time-stepping schemes for the nonlinear abstract ODE. The nonlinear stability and convergence are rigorously analysed once the spatial differential operator is approximated by an appropriate positive semi-definite matrix under some suitable smoothness assumptions. With regard to the two dimensional Dirichlet or Neumann boundary problems, our new time-stepping schemes coupled with discrete Fast Sine / Cosine Transformation can be applied to simulate the two-dimensional nonlinear Klein–Gordon equations effectively. All essential features of the methodology are present in one-dimensional and two-dimensional cases, although the schemes to be analysed lend themselves with equal to higher-dimensional case. The numerical simulation is implemented and the numerical results clearly demonstrate the advantage and effectiveness of our new schemes in comparison with the existing numerical methods for solving nonlinear Klein–Gordon equations in the literature. © 2017 Elsevier Inc.


Tao Y.,Nanjing University of Posts and Telecommunications | Yuan K.,Nanjing University of Posts and Telecommunications | Chen T.,Nanjing University of Posts and Telecommunications | Xu P.,Nanjing University of Posts and Telecommunications | And 6 more authors.
Advanced Materials | Year: 2014

The design and characterization of thermally activated delayed fl uorescence (TADF) materials for optoelectronic applications represents an active area of recent research in organoelectronics. Noble metal-free TADF molecules offer unique optical and electronic properties arising from the effi cient transition and interconversion between the lowest singlet (S 1 ) and triplet (T 1 ) excited states. Their ability to harvest triplet excitons for fl uorescence through facilitated reverse intersystem crossing (T 1 ?S 1 ) could directly impact their properties and performances, which is attractive for a wide variety of low-cost optoelectronic devices. TADF-based organic light-emitting diodes, oxygen, and temperature sensors show signifi cantly upgraded device performances that are comparable to the ones of traditional rare-metal complexes. Here we present an overview of the quick development in TADF mechanisms, materials, and applications. Fundamental principles on design strategies of TADF materials and the common relationship between the molecular structures and optoelectronic properties for diverse research topics and a survey of recent progress in the development of TADF materials, with a particular emphasis on their different types of metal-organic complexes, D-A molecules, and fullerenes, are highlighted. The success in the breakthrough of the theoretical and technical challenges that arise in developing high-performance TADF materials may pave the way to shape the future of organoelectronics. © 2014 WILEY-VCH Verlag GmbH &Co.KGaA,Weinheim.


Yang J.,Nanjing University of Technology | Ma M.,Nanjing University of Technology | Li L.,Nanjing University of Technology | Zhang Y.,Nanjing University of Technology | And 4 more authors.
Nanoscale | Year: 2014

Graphene, an atomic-scale honeycomb crystal lattice, is increasingly becoming popular because of its excellent mechanical, electrical, chemical, and physical properties. However, its zero bandgap places restrictions on its applications in field-effect transistors (FETs). Graphene nanomesh (GNM), a new graphene nanostructure with a tunable bandgap, shows more excellent performance. It can be widely applied in electronic or photonic devices such as highly sensitive biosensors, new generation of spintronics and energy materials. These illustrate significant opportunities for the industrial use of GNM, and hence they push nanoscience and nanotechnology one step toward practical applications. This review briefly describes the current status of the design, synthesis, and potential applications of GNM. Finally, the perspectives and challenges of GNM development are presented and some suggestions are made for its further development and exploration. This journal is © The Royal Society of Chemistry.


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.


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.


Xu B.,Nanjing University of Technology | Liu Y.,Nanjing University of Technology | Yin X.,Nanjing University of Technology | Yang W.,Nanjing University of Technology | Chen Y.,Jiangsu Polytechnic University
Corrosion Science | Year: 2013

The corrosion inhibition effect of 3-pyridinecarboxaldehyde thiosemicarbazone (3-PCT) on mild steel was studied in 1. M HCl solution by means of weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. The surface morphology of mild steel was examined with scanning electron microscopy (SEM) and the mechanism of inhibition was determined by the potential of zero charge (PZC) measurement at the metal-solution interface. Then molecular dynamics simulations were also executed for 3-PCT. The results show that 3-PCT is a good corrosion inhibitor, retarding both cathodic and anodic reactions in hydrochloric acid. The adsorption of 3-PCT on the mild steel surface obeys the Langmuir isotherm, and the thermodynamic parameters (Kads,Ea,δGads0) were also determined and discussed. © 2013 Elsevier Ltd.


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.


Cheng T.,Nanjing University of Posts and Telecommunications | Zhang Y.,Nanjing University of Posts and Telecommunications | Lai W.-Y.,Nanjing University of Posts and Telecommunications | Lai W.-Y.,Nanjing University of Technology | And 2 more authors.
Advanced Materials | Year: 2015

Flexible and stretchable electronics represent today's cutting-edge electronic technologies. As the most-fundamental component of electronics, the thin-film electrode remains the research frontier due to its key role in the successful development of flexible and stretchable electronic devices. Stretchability, however, is generally more challenging to achieve than flexibility. Stretchable electronic devices demand, above all else, that the thin-film electrodes have the capacity to absorb a large level of strain (>>1%) without obvious changes in their electrical performance. This article reviews the progress in strategies for obtaining highly stretchable thin-film electrodes. Applications of stretchable thin-film electrodes fabricated via these strategies are described. Some perspectives and challenges in this field are also put forward. Progress in strategies for obtaining highly stretchable thin-film electrodes is reviewed. Such electrodes display tremendous potential in applications for flexible and stretchable electronics, such as stretchable displays, electronic skin, and wearable electronics. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Kai Y.,Nanjing University of Technology | Hu Y.,Nanjing University of Technology | Tang R.,Nanjing University of Technology | Meng Z.,Nanjing University of Technology
Fluid Phase Equilibria | Year: 2013

The solubilities of dimethyl fumarate in methanol. +. water, ethanol. +. water, 1-propanol. +. water mixed solvents were measured within the temperature range 278.15-333.15. K at atmospheric pressure by the dynamic method. The solubility of dimethyl fumarate in those selected solvents increased with increasing temperature, but the rate of solubility is different. The semi-empirical Buchwski-Ksiazaczak λh equation and the modified Apelblat equation were used to correlate with the solubility. The RMSD (root-mean-square deviations) <2.7 and the RD (relative deviation) <6.39. By comparing the two models, Apelblat equation describes the solubility of dimethyl fumarate in selected solvents as a function of temperature well. The thermodynamic properties of the solution process, including the enthalpy, and entropy were calculated by the van't Hoff analysis and they were positive. © 2013.


Jiang X.,Nanjing University of Technology | Hu Y.,Nanjing University of Technology | Meng Z.,Nanjing University of Technology | Yang W.,Nanjing University of Technology
Fluid Phase Equilibria | Year: 2013

Data on corresponding solid-liquid equilibrium of succinic acid in different aqueous solvent mixtures was measured with temperature range from 278.15. K to 333.15. K under atmospheric pressure by employing the gravimetric method. The experimental results indicated that the solubility of succinic acid in the binary mixtures increases with increasing both temperature and mass fraction of organic solvents. The experimental data were well-correlated with the modified Apelblat equation, the λh equation and the van't Hoff equation. In addition, the calculated solubilities showed good agreement with the experimental results. It was found that the modified Apelblat equation could obtain the better correlation results than the other two models. The standard enthalpy, standard entropy, and Gibbs free energy change of solution of succinic acid were calculated from the solubility data by using the modified Apelblat model. Moreover, the experimental data and model parameters would be useful for optimizing the process of purification of succinic acid in industry. © 2012.


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.


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.


Wang X.,Nanjing University of Technology | Chang H.,Nanjing University of Technology | Xie J.,Nanjing University of Posts and Telecommunications | Zhao B.,Nanjing University of Technology | And 7 more authors.
Coordination Chemistry Reviews | Year: 2014

Lanthanide-based luminescent probes have attracted increasing attention due to their unique optical properties, such as large Stokes and/or anti-Stokes shifts, long luminescence lifetimes (up to milliseconds), and narrow and compound-independent emission bands, making them widely employed in detection, diagnosis, and bioimaging. This review focuses on the recent developments of lanthanide-based luminescent probes including lanthanide complexes and lanthanide nanoparticles for probing pH, anions, metal ions, reactive oxygen species, and biomolecules (amino acids, proteins, nucleobases, and nucleic acids). The design principles and recognition mechanisms of luminescent probes based on lanthanide ions for various analytes are elaborated in detail. In the end, future research directions with great potentials and the according challenges of lanthanide-based luminescent probes are also discussed. © 2014 Elsevier B.V.


Deng R.,National University of Singapore | Qin F.,National University of Singapore | Chen R.,Nanjing University of Posts and Telecommunications | Huang W.,Nanjing University of Posts and Telecommunications | And 4 more authors.
Nature Nanotechnology | Year: 2015

Developing light-harvesting materials with tunable emission colours has always been at the forefront of colour display technologies. The variation in materials composition, phase and structure can provide a useful tool for producing a wide range of emission colours, but controlling the colour gamut in a material with a fixed composition remains a daunting challenge. Here, we demonstrate a convenient, versatile approach to dynamically fine-tuning emission in the full colour range from a new class of core-shell upconversion nanocrystals by adjusting the pulse width of infrared laser beams. Our mechanistic investigations suggest that the unprecedented colour tunability from these nanocrystals is governed by a non-steady-state upconversion process. These findings provide keen insights into controlling energy transfer in out-of-equilibrium optical processes, while offering the possibility for the construction of true three-dimensional, full-colour display systems with high spatial resolution and locally addressable colour gamut. © 2015 Macmillan Publishers Limited. All rights reserved.


Liu X.,National University of Singapore | Deng R.,National University of Singapore | Zhang Y.,National University of Singapore | Wang Y.,National University of Singapore | And 4 more authors.
Chemical Society Reviews | Year: 2015

Probing the nature of nanocrystalline materials such as the surface state, crystal structure, morphology, composition, optical and magnetic characteristics is a crucial step in understanding their chemical and physical performance and in exploring their potential applications. Upconversion nanocrystals have recently attracted remarkable interest due to their unique nonlinear optical properties capable of converting incident near-infrared photons to visible and even ultraviolet emissions. These optical nanomaterials also hold great promise for a broad range of applications spanning from biolabeling to optoelectronic devices. In this review, we overview the instrumentation techniques commonly utilized for the characterization of upconversion nanocrystals. A considerable emphasis is placed on the analytical tools for probing the optical properties of the luminescent nanocrystals. The advantages and limitations of each analytical technique are compared in an effort to provide a general guideline, allowing optimal conditions to be employed for the characterization of such nanocrystals. Parallel efforts are devoted to new strategies that utilize a combination of advanced emerging tools to characterize such nanosized phosphors. This journal is © The Royal Society of Chemistry.


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.


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.


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.


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.


Li X.,Nanjing Forestry University | Dou W.,Nanjing Forestry University | Bao N.,Nanjing University of Technology
Materials Letters | Year: 2012

ZnO tubes with diameters ranging from tens of nanometers to several microns were prepared via hydrothermal reactions using surfactants as structure-directing agents. All tubular ZnO materials are indexed to a hexagonal structure of wurtzite. The room-temperature photoluminescence spectra of ZnO tubes reveal a strong UV emission at around 387 nm and broad and a relative weak visible emission with main peak identified at 510-520 nm, depending on the size of ZnO tubes. © 2011 Elsevier B.V. All rights reserved.


Zhan B.,Nanjing University of Posts and Telecommunications | Li C.,Nanjing University of Posts and Telecommunications | Yang J.,Nanjing University of Posts and Telecommunications | Yang J.,Nanjing University of Technology | And 5 more authors.
Small | Year: 2014

Graphene, because of its excellent mechanical, electrical, chemical, physical properties, sparked great interest to develop and extend its applications. Particularly, grapheme based fi eld-effect transistors (GFETs) present exciting and bright prospects for sensing applications due to their greatly higher sensitivity and stronger selectivity. This Review highlights a selection of important topics pertinent to GFETs and their application in electronic sensors. This article begins with a description of the fabrications and characterizations of GFETs, and then introduces the new developments in physical, chemical, and biological electronic detection using GFETs. Finally, several perspective and current challenges of GFETs development are presented, and some proposals are suggested for further development and exploration. © 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.


Qian J.,Jiangsu Polytechnic University | Qian J.,Nanjing University of Technology | Shi H.,Nanjing University of Technology | Yun Z.,Nanjing University of Technology
Bioresource Technology | Year: 2010

In the present work the preparation of biodiesel from Jatropha curcas L. oil produced by two-phase solvent extraction (TSE) was studied. The experimental results of TSE process showed that the optimal extraction conditions were 30 g samples, 240 mL of extraction solvent mixture and methanol/n-hexane volume ratio 60:40, extraction temperature 35 °C, extraction time 30 min. Further, the effect of methanol recycling on the TSE process was also investigated. After TSE process, the investigations were carried out on transesterification of methanol with oil-n-hexane solution coming from TSE process in the presence of sodium hydroxide as the catalyst. The conversion could achieve 98% with 3:1 n-hexane/oil weight ratio, 60 °C reaction temperature, 7:1 methanol/oil mole ratio, 1.1% alkali catalyst concentration and 120 min reaction time. The properties of fatty acid methyl ester (FAME) product prepared from Jatropha curcas L. oil produced by two-phase solvent extraction met the ASTM specifications for biodiesel. Crown © 2010 Published by Elsevier Ltd. All rights reserved.


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.


Tan C.,Nanyang Technological University | Qi X.,Singapore Institute of Manufacturing Technology | Huang X.,Nanyang Technological University | Yang J.,Nanyang Technological University | And 8 more authors.
Advanced Materials | Year: 2014

Single-layer transition metal dichalcogenide nanosheets including MoS 2, TiS2 and TaS2 can be used as novel platforms for the fluorescence enhancement of aggregation-induced emission fluorophores. The small organic AIE unit can be assembled into a two-dimensional sheet structure via a simple precipitation technique assisted by these monolayers. The resultant organic sheets possess a size of 0.2-2 μm and a thickness of 9-20 nm. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Xu B.,Nanjing University of Technology | Yang W.,Nanjing University of Technology | Liu Y.,Nanjing University of Technology | Yin X.,Nanjing University of Technology | And 2 more authors.
Corrosion Science | Year: 2014

The inhibition effect of two Schiff's base derivatives on the corrosion of mild steel in 1.0. M HCl solution was studied by electrochemical techniques, SEM and theoretical calculation methods. The experimental results show that the inhibition efficiency of 2-pyridinecarboxaldehyde thiosemicarbazone (2-PCT) is higher than that of 4-pyridinecarboxaldehyde thiosemicarbazone (4-PCT), and both the two compounds are good inhibitors for mild steel in 1.0. M HCl. Potentiodynamic polarization curves show that the two inhibitors act as mixed type inhibitors. The adsorption of inhibitors obeys the Langmuir adsorption isotherm, and the thermodynamic parameters (Ea, Kads, δGads0) were calculated and discussed. The mechanism of inhibition was determined by PZC measurements and theoretical calculation methods. © 2013 Elsevier Ltd.


Zhang K.,Nanjing University of Technology | Xu B.,Nanjing University of Technology | Yang W.,Nanjing University of Technology | Yin X.,Nanjing University of Technology | And 2 more authors.
Corrosion Science | Year: 2015

Two novel imidazoline derivatives, 2-(2-trifluoromethyl-4,5-dihydro-imidazol-1-yl)-ethylamine (1-IM) and 2-(2-trichloromethyl-4,5-dihydro-imidazol-1-yl)-ethylamine (2-IM), have been investigated as corrosion inhibitors for mild steel in 0.5M HCl solution by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests. The surface morphology of sample was presented through scanning electron microscope (SEM) and the inhibition mechanism was elucidated by measuring the potential of zero charge (Epzc) at the solid/liquid interface. Results of theoretical calculation confirm that the chloride-substituted compound shows better inhibitive performance than the fluoride-substituted one. © 2014 Elsevier Ltd.


Wang X.,Nanjing University | Wang X.,Nanjing University of Technology | Cui S.,Beijing Normal University | Wang Y.,Beijing Normal University | And 2 more authors.
Chemical Science | Year: 2013

Recognition of DNA depurination is of great importance for early cancer detection. Current analytical methods for this purpose are usually complicated. Luminescent lanthanide complexes possess some fascinating optical properties that have shown potential applications in biomedical research. In this study, a novel terbium(iii) complex (TbL) has been demonstrated to be capable of recognizing purine nucleobases in DNA as a selective time-resolved luminescence probe. TbL consists of a luminescent terbium(iii) center and two nitroimidazole groups linked by a linear polydentate ligand. The luminescence of TbL is enhanced remarkably upon reaction with oligonucleotides or natural DNA containing purine bases in aqueous solution, while it is quenched dramatically as depurination occurs to DNA. Mechanistic studies using circular dichroism and fluorescence spectroscopies reveal that the luminescence enhancement results from the preferential intercalation between the nitroimidazole moieties of TbL and the purine bases of DNA, which regulate the electron withdrawing effect of nitro groups via hydrogen bonds and thereby affect the energy transfer from the ligand to the metal center of the probe. This mechanism is also supported by molecular dynamics simulation results for the reaction. The distinct luminescence responses of TbL in the presence and absence of purine bases in DNA make it a sensitive probe for DNA depurination in physiological conditions. © 2013 The Royal Society of Chemistry.


Zhu G.,Nanjing University of Posts and Telecommunications | He Z.,Nanjing University of Posts and Telecommunications | Chen J.,Nanjing University of Posts and Telecommunications | Zhao J.,Nanjing University of Posts and Telecommunications | And 6 more authors.
Nanoscale | Year: 2014

Carbon nanotube (CNT)-graphene hybrids grown on porous Ni foam are used as substrates to immobilize MnO2 nanoflakes, thus forming three-dimensional (3D) MnO2-CNT-graphene-Ni hybrid foam. The as-prepared hybrid materials could be used as supercapacitor electrodes directly without any binder and conductive additives, and fully maintain the high conductivity and high surface-to-volume ratio of CNTs, large pseudocapacitance of MnO2 nanoflakes and high porosity provided by the framework of Ni foam. The conductivity of the 3D MnO2-CNT-graphene-Ni foam is as high as 117 S cm-1 due to the seamless integration of MnO2 nanoflakes, CNTs, graphene and Ni foam among the 3D frameworks, which guarantee its low internal resistance (1.25 ohm) when compacted into supercapacitor devices. In aqueous electrolytes, the 3D MnO2-CNT-graphene-Ni based prototype supercapacitors show specific capacitances of ∼251 F g -1 with good cycling stability at a current density of 1.0 A g -1. In addition, these 3D hybrids also demonstrate their potential in all-solid-state flexible supercapacitors. © 2013 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.


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.


Dai W.,Zhejiang Normal University | Hu J.,Zhejiang Normal University | Zhou L.,Zhejiang Normal University | Li S.,Nanjing University of Technology | And 2 more authors.
Energy and Fuels | Year: 2013

A new type of composite adsorbent, MOF-5/Cu(I), was prepared by MOF-5 doped with different amount of CuCl using a spontaneous monolayer dispersion technique. These new composite adsorbents were characterized by X-ray diffraction, thermogravimetric analysis, electrondispersion X-ray scope, and N2 adsorption, respectively. The desulfurizaion performance of the prepared adsorbents was evaluated by the selective adsorption of dibenzothiophene from the simulated oils in a fixed-bed breakthrough column at room temperature. From the obtained breakthrough curves, both the breakthrough capacity and the saturation capacity of the adsorbents for sulfur element were determined. The results show that MOF-5/Cu(I) exhibited high desulfurization capacities, which are superior to those reported previously in the literature. In addition, these novel composite adsorbents possessed good durability and affinities for the adsorption of dibenzothiophene in the presence of aromatic components and moisture. The saturated composite adsorbent MOF-5/Cu(I) can be regenerated with nitrogen atmosphere sweeping at 623 K for 4 h. About 97% of the desulfurization capacity was recovered after regeneration. © 2013 American Chemical Society.


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.


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.


Liu X.,Nanjing University of Posts and Telecommunications | Long Q.,Nanjing University of Posts and Telecommunications | Jiang C.,Nanjing University of Posts and Telecommunications | Zhan B.,Nanjing University of Posts and Telecommunications | And 6 more authors.
Nanoscale | Year: 2013

Nanostructured Co3O4 materials attracted significant attention due to their exceptional electrochemical (pseudo-capacitive) properties. However, rigorous preparation conditions are needed to control the size (especially nanosize), morphology and size distribution of the products obtained by conventional methods. Herein, we describe a novel one step shape-controlled synthesis of uniform Co3O4 nanocubes with a size of 50 nm with the existence of mesoporous carbon nanorods (meso-CNRs). In this synthesis process, meso-CNRs not only act as a heat receiver to directly obtain Co3O4 eliminating the high-temperature post-calcination, but also control the morphology of the resulting Co 3O4 to form nanocubes with uniform distribution. More strikingly, mesoporous Co3O4 nanocubes are obtained by further thermal treatment. The structure and morphology of the samples were characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffraction. A possible formation mechanism of mesoporous Co 3O4 nanocubes is proposed here. Electrochemical tests have revealed that the prepared mesoporous Co3O4 nanocubes demonstrate a remarkable performance in supercapacitor applications due to the porous structure, which endows fast ion and electron transfer. © 2013 The Royal Society of Chemistry.


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.


Wang Y.,Nanjing University of Technology | He C.,Beijing Normal University | Xing W.,Nanjing University of Technology | Li F.,Nanjing University of Technology | And 4 more authors.
Advanced Materials | Year: 2010

(Figure Presented) Nondestructive preparation of bicontinuous nanoporous metal membranes by replication of bicontinuous nanoporous polymeric membranes consisting of recoverable asymmetric block copolymers (BCPs) is reported. The BCP membranes are generated by swelling the minority domains of the BCP with selective solvents accompanied by reconstruction of the glassy matrix formed by the majority component (see figure). © 2010 WILEY-VCH Verlag GmbH & Co. KGaA.


Tang Y.,Nanjing University of Technology | Yang X.,Nanjing University of Technology | Yang W.,Nanjing University of Technology | Wan R.,Nanjing University of Technology | And 2 more authors.
Corrosion Science | Year: 2010

The efficiency, as steel corrosion inhibitors in 0.5 M H2SO4, of two thiadiazole derivatives, 2-amino-5-(3-pyridyl)-1,3,4-thiadiazole (3-APTD) and 2-amino-5-(4-pyridyl)-1,3,4-thiadiazole (4-APTD), was investigated by polarization and electrochemical impedance spectroscopy. The protection efficiency increases with increasing inhibitors concentration, but the temperature has hardly effect on the inhibition efficiency of APTD. The adsorption of APTD on iron surface obeys the Langmuir isotherm. The experimental results show that the inhibition efficiency of 4-APTD is higher than that of 3-APTD, and the molecular dynamics (MD) simulations show that the adsorption of 4-APTD on iron surface has the higher binding energy than that of 3-APTD. © 2010 Elsevier Ltd. All rights reserved.


Tang Y.,Nanjing University of Technology | Yang X.,Nanjing University of Technology | Yang W.,Nanjing University of Technology | Chen Y.,Jiangsu Polytechnic University | Wan R.,Nanjing University of Technology
Corrosion Science | Year: 2010

The corrosion inhibition of mild steel in 0.5 M H2SO4 and 1.0 M HCl by 2-amino-5-phenyl-1,3,4-thiadiazole (APT) has been studied using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. The results show that the inhibition efficiency increases with the increase of APT concentration in both acids, and the higher inhibition efficiency is obtained in 0.5 M H2SO4. The adsorption of APT molecules on the steel surface obeys Langmuir adsorption isotherm in both acids, and occurs spontaneously. The molecular dynamics method has also been used to simulate the adsorption of ATP molecule and solvent ions on the iron surface. The results show that with the adsorption of sulfate ions the Fe + anion + APT system has the higher negative interaction energy comparing to the case of the adsorption of chloride ions. © 2009 Elsevier Ltd. All rights reserved.


Ai W.,Nanyang Technological University | Luo Z.,Nanyang Technological University | Jiang J.,Nanyang Technological University | Zhu J.,Nanyang Technological University | And 7 more authors.
Advanced Materials | Year: 2014

N and S codoping of graphene is realized by a novel approach: covalent functionalization of graphene oxide using 2-aminothiophenol as a source of both N and S followed by thermal treatment. The resulting N- and S-codoped graphene has potential applications in high-performance lithium-ion batteries and as a metal-free catalyst for oxygen reduction reaction. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Song T.-S.,Nanjing University of Technology | Tan W.-M.,China National Offshore Oil Corporation | Wu X.-Y.,Nanjing University of Technology | Zhou C.C.,Nanjing University of Technology
Journal of Chemical Technology and Biotechnology | Year: 2012

Background: Sediment microbial fuel cells (SMFCs) could be used as power sources and one type of new technology for the removal of organic matters in sediments. Various types of materials have been used as electrodes. Nevertheless, there is still room to improve electrode materials and enhance their effect on the performance of SMFCs. In this work, performances of SMFCs with activated carbon fiber felt (ACFF) and with nitric acid-treated ACFF were compared with graphite felt (GF) materials. Results: The maximum power density of the SMFC with ACFF electrode was the highest (33.5 ± 1.5 mW m -2). Nitric acid-treated GF electrode slightly increased the maximum power density of SMFC, while the nitric acid treated-ACFF resulted in significant decline in the maximum power density of SMFC. The maximum power density further increased to 74.5 ± 7.5 mW m -2 in SMFC using GF cathode and ACFF anode. Conclusions: ACFF as anode can enhance the transport of electrons from the oxidation of organic matter in the sediment, while the output power was found to reduce in SMFC with ACFF cathode. Further efforts are needed to study the formation conditions of the biocathode and new electrode modification technology. © 2012 Society of Chemical Industry.


Zhuang H.,Nanjing University of Technology | Wu X.,Shanghai Branch of Beijing Urban Engineering Design and Research Institute Co. | Chen G.,Nanjing University of Technology
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2011

According to the limitation of existed methods used to analyze the earthquake response of soil-structure dynamic interaction, the nonlinear static and dynamic coupling interaction of soil-underground structure theory and calculation model are developed. Based on the model, the earthquake response and damage mechanism of subway station with two layers and three spans are analyzed, respectively. The research results show that: (1) Under the static and dynamic coupling loadings, the damage orders of subway station members are obtained in detail. The lower surface of middle slab near to the lateral wall is damaged firstly; and the severely damages take place on the ends of middle columns. The lower surface of the top slab near to the lateral wall, the upper surface of bottom slab on the side span, and the upper surface of top slab near to the middle column are damaged in turns. (2) As a whole, the ends of middle columns and the bottoms of lateral walls are damaged more easily and severely. The members of subway station are almost damaged by tensioning or compressing respectively when weak earthquake ground motion is inputted. However, when the earthquake ground motion become stronger, these members are damaged by tensioning and compressing simultaneously. (3) At the same time, the subway station may be damaged more easily and severely by near field earthquake.


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.


Tan C.,Nanyang Technological University | Liu Z.,Nanyang Technological University | Liu Z.,Nanjing University of Posts and Telecommunications | Huang W.,Nanjing University of Posts and Telecommunications | And 2 more authors.
Chemical Society Reviews | Year: 2015

Ultrathin two-dimensional (2D) nanomaterials, such as graphene and MoS2, hold great promise for electronics and optoelectronics due to their distinctive physical and electronic properties. Recent progress in high-yield, massive production of ultrathin 2D nanomaterials via various solution-based methods allows them to be easily integrated into electronic devices via solution processing techniques. Non-volatile resistive memory devices based on ultrathin 2D nanomaterials have been emerging as promising alternatives for the next-generation data storage devices due to their high flexibility, three-dimensional-stacking capability, simple structure, transparency, easy fabrication and low cost. In this tutorial review, we will summarize the recent progress in the utilization of solution-processed ultrathin 2D nanomaterials for fabrication of non-volatile resistive memory devices. Moreover, we demonstrate how to achieve excellent device performance by engineering the active layers, electrodes and/or device structure of resistive memory devices. On the basis of current status, the discussion is concluded with some personal insights into the challenges and opportunities in future research directions. © 2015 The Royal Society of Chemistry.


Zeng C.,Nanjing University of Technology
Industrial and Engineering Chemistry Research | Year: 2012

Zeolite A/chitosan hybrid microspheres with uniform particle size of ∼700 μm and high crushing strength were prepared by bioorganic molecule-assisted impregnation-gelation-hydrothermal synthesis of silica/chitosan hybrid microspheres in a sodium aluminate alkaline solution. Binderless zeolite A microspheres with similar particle size and medium crashing strength were subsequently obtained after calcination of the zeolite A/chitosan hybrid microspheres. The silica/chitosan hybrid microspheres were prepared by solidification of chitosan microdroplets, which were formed in a microfluidic device from a silica sol-chitosan aqueous solution, in the sodium aluminate alkaline solution. X-ray diffraction, FT-IR, scanning and transmission electron microscopy, thermogravimetric analysis, and adsorption were applied to examine the obtained products. The zeolite A/chitosan hybrid microspheres are composed of zeolite A crystals with particle sizes of 200-400 nm and chitosan, with zeolite A crystals covered with and linked by chitosan. Removal of chitosan in the zeolite A/chitosan hybrid microspheres by calcination has no influence on the structure of the microspheres. Furthermore, the resulting binderless zeolite A microspheres exhibit a high surface area of 30 m 2 g -1, high static water adsorption amount of 290 mg g -1, and quite different adsorption capacities for CH 4 from H 2, with a high ideal separation factor for CH 4/H 2 of 12. The crushing strength of binderless zeolite A microspheres can be greatly enhanced after a secondary growth. In addition, the formation process of the microspheres was analyzed. © 2012 American Chemical Society.


Zhang J.,Nanjing University of Posts and Telecommunications | Wang L.,Nanjing University of Posts and Telecommunications | Liu X.,Nanjing University of Science and Technology | Li X.,Nanjing University of Posts and Telecommunications | And 2 more authors.
Journal of Materials Chemistry A | Year: 2015

A dense array of CdS-ZnS core-shell nanorods film (1D vertically aligned) was synthesized through a simple two-step aerosol assisted chemical vapor deposition (AACVD) method. In this configuration, a ZnS nanocrystal (protective shell) was grown in situ on a CdS core, forming nanorod heterostructures to restrain the photo-corrosion and enhance the charge separation and transportation efficiencies of CdS cores. The as-prepared CdS-ZnS films showed elevated photoelectrochemical (PEC) performance (over four times than that of uncoated CdS arrays) with a significant photocurrent density of 7.8 mA cm-2 (0 V, vs. SCE) and incident photon to electron conversion efficiency (IPCE) values above 35% under AM 1.5G irradiation. Moreover, the stability of the photoelectrode was tested for over 16 min. These results suggest that the dense array of CdS-ZnS core-shell heterostructures provides a unique spatial distribution of the photo-excited charge carriers, as well as stable anti-photo-corrosion ability, and therefore is promising to be a photoelectrode in PEC hydrogen generation from water. This journal is © 2015 The Royal Society of Chemistry.


Wang W.,Nanjing University of Technology | Dong X.,Nanjing University of Technology | Nan J.,Nanjing University of Technology | Jin W.,Nanjing University of Technology | And 3 more authors.
Chemical Communications | Year: 2012

For the first time, a homochiral metal-organic framework membrane was prepared for the enantioselective separation of important chiral compounds, especially chiral drug intermediates, which will allow for the potential development of a new, sustainable and highly efficient chiral separation technique. © The Royal Society of Chemistry 2012.


Zhang F.,Nanjing University of Technology | Tang Y.,Nanjing University of Technology | Cao Z.,Nanjing University of Technology | Jing W.,State Key Laboratory of Material Oriented Chemical Engineering | And 3 more authors.
Corrosion Science | Year: 2012

Inhibition performance of 2-(4-pyridyl)-benzimidazole (PBI) against corrosion of mild steel in 1.0. M HCl was investigated by weight loss and electrochemical measurements. The inhibition efficiency increased with increasing inhibitor's concentration, but decreased with the increase in temperature and concentration of the acid. The theoretical results from DFT and MD simulations reveal that adsorption of PBI depends on the formation of coordinative bonds between PBI molecule and iron surface, and the binding energy between PBI molecule and iron surface is the highest among the three studied compounds. © 2012 Elsevier Ltd.


Sun H.,Nanjing University of Posts and Telecommunications | Sun H.,Nanjing University of Technology | Liu S.,Nanjing University of Posts and Telecommunications | Lin W.,Nanjing University of Posts and Telecommunications | And 10 more authors.
Nature Communications | Year: 2014

Smart luminescent materials that are responsive to external stimuli have received considerable interest. Here we report ionic iridium (III) complexes simultaneously exhibiting mechanochromic, vapochromic and electrochromic phosphorescence. These complexes share the same phosphorescent iridium (III) cation with a N-H moiety in the N^N ligand and contain different anions, including hexafluorophosphate, tetrafluoroborate, iodide, bromide and chloride. The anionic counterions cause a variation in the emission colours of the complexes from yellow to green by forming hydrogen bonds with the N-H proton. The electronic effect of the N-H moiety is sensitive towards mechanical grinding, solvent vapour and electric field, resulting in mechanochromic, vapochromic and electrochromic phosphorescence. On the basis of these findings, we construct a data-recording device and demonstrate data encryption and decryption via fluorescence lifetime imaging and time-gated luminescence imaging techniques. Our results suggest that rationally designed phosphorescent complexes may be promising candidates for advanced data recording and security protection. © 2014 Macmillan Publishers Limited. All rights reserved.


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.


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.


Shi Q.,Nanjing University of Technology | Shi Q.,Yancheng Institute of Technology | Zhang H.,Nanjing University of Technology
Journal of Rare Earths | Year: 2012

The effect of Fe doping on the electrical properties of lanthanum silicates was investigated. The apatite-type lanthanum silicates La10Si 6-xFexO27-x/2 (x=0.2, 0.4, 0.6, 0.8, 1.0) were synthesized via sol-gel process. The unit cell volume increased with Fe doping because the ionic radius of Fe3+ ion is larger than that of Si 4+ ion. The conductivities of La10Si6-xFe xO27-x/2 first increased and then decreased with the increasing of Fe content. The increase of the conductivity might be attributed to the distortion of the cell lattice, which assisted the migration of the interstitial oxygen ions. The decrease of the conductivity might be caused by the lower concentration of interstitial oxygen ions. The optimum Fe doping content in lanthanum silicates was 0.6. La10Si5.4Fe 0.6O26.7 exhibited the highest ionic conductivity of 2.712×10-2 S/cm at 800°C. The dependence of conductivity on oxygen partial pressure p(O2) suggested that the conductivity of La10Si6-xFexO27-x/2 was mainly contributed by ionic conductivity. © 2012 The Chinese Society of Rare Earths.


Liu X.-M.,Nanjing University of Technology | Yan P.,Nanjing University of Technology | Xie Y.-Y.,Sinopoly Battery Ltd | Yang H.,Nanjing University of Technology | And 3 more authors.
Chemical Communications | Year: 2013

LiFePO4/C nanocomposites with excellent electrochemical performance is synthesized from nano-FePO4, generated by a novel method using a confined area impinging jet reactor (CIJR). When discharged at 80 C (13.6 Ag-1), the LiFePO4/C delivers a discharge capacity of 95 mA h g-1, an energy density of 227 W h kg-1 and a power density of 34 kW kg-1. © 2013 The Royal Society of Chemistry.


Shi R.,Nanjing University of Technology | Shao J.,Yancheng Institute of Technology | Zhu X.,Nanjing University of Technology | Lu X.,Nanjing University of Technology
Journal of Physical Chemistry C | Year: 2011

A MD simulation method is used to simulate the melting and freezing of Au-Pt nanoparticles confined in armchair single-walled carbon tubes ((n,n)-SWNTs), applying the second-moment approximation of the tight-binding potentials for metal-metal interactions and Lennard-Jones potential for the metal-carbon interactions. The carbon atoms on the SWNTs are taken to be fixed. The structures, total energies, Lindemman indices, and radial and axial density distributions are used to examine the behaviors of melting and freezing for Au-Pt nanoparticles confined in (n,n)-SWNTs. The nucleation analysis is carried out in terms of classical nucleation theory. The simulation results demonstrate that the solid Au-Pt clusters confined within (n,n)-SWNTs have multishell structures, even in a melted cluster. In addition, for the confined Au-Pt nanoparticles, Pt atoms tend to stay at the position close to the SWNT wall, which is different from free Au-Pt nanoparticles. Simulation results reveal that SWNTs and compositions of nanoparticles have significant effects on the structures and physical properties of the confined Au-Pt nanoparticles. On the other hand, some important thermodynamic and dynamic parameters are estimated based on MD simulations and compared with available theoretical and experimental results. © 2011 American Chemical Society.


Koumoto K.,Nagoya University | Funahashi R.,Japan National Institute of Advanced Industrial Science and Technology | Guilmeau E.,CRISMAT Laboratory | Miyazaki Y.,Tohoku University | And 4 more authors.
Journal of the American Ceramic Society | Year: 2013

Metal oxides (Ca3Co4O9, CaMnO3, SrTiO3, In2O3), Ti sulfides, and Mn silicides are promising thermoelectric (TE) material candidates for cascade-type modules that are usable in a temperature range of 300-1200 K in air. In this paper, we review previous studies in the field of TE materials development and make recommendations for each material regarding future research. Furthermore, the R&D of TE modules composed of metal oxide materials and the prospect of their commercialization for energy harvesting is demonstrated. © 2012 The American Ceramic Society.


Zhang D.,Nanjing University of Technology | Cai R.,Nanjing University of Technology | Zhou Y.,Nanjing University of Technology | Shao Z.,Nanjing University of Technology | And 2 more authors.
Electrochimica Acta | Year: 2010

Effects of ball milling way and time on the phase formation, particulate morphology, carbon content, and consequent electrode performance of LiFePO4/C composite, prepared by high-energy ball milling of Li2CO3, NH4H2PO4, FeC2O4 raw materials with citric acid as organic carbon source followed by thermal treatment, were investigated. Three ball milling ways and five different milling durations varied from 0 to 8 h were compared. LiFePO4/C composites could be obtained from all synthesis processes. TEM examinations demonstrated LiFePO4/C from ball milling in acetone resulted in sphere shape grains with a size of ∼60 nm, similar size was observed for LiFePO4/C from dry ball milling but in a more irregular shape. The ball milling in benzene resulted in a much larger size of ∼250 nm. The LiFePO4/C composites prepared from dry ball milling and ball milling in acetone showed much better electrochemical performance than that from ball milling in benzene. SEM examinations and BET measurements demonstrated that the high-energy ball milling effectively reduced the grain size. A ball milling for 4 h resulted in the best electrochemical performance, likely due to the proper amount of carbon and proper carbon structure were created. © 2009 Elsevier Ltd. All rights reserved.


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.


Cao Z.,Nanjing University of Technology | Tang Y.,Nanjing University of Technology | Cang H.,Yancheng Institute of Technology | Xu J.,Nanjing University of Technology | And 2 more authors.
Corrosion Science | Year: 2014

In this paper, the adsorption behavior and inhibition mechanism of 2-aminomethyl benzimidazole (ABI), bis(2-benzimidazolylmethyl) amine (BBIA) and tri-(2-benzimidazolylmethyl) amine (TBIA) on the surface of mild steel were studied by quantum chemical calculations and molecular dynamics (MD) simulations. It was found that the three molecules show the similar ability to donate electrons while the difference in inhibition performance should mainly be attributed to the difference in accepting electrons. MD simulations show that steric effect between the benzimidazole segments significantly affects the adsorptive configurations of the molecules on Fe (100) surface. © 2014 Elsevier Ltd.


Grant
Agency: European Commission | Branch: H2020 | Program: RIA | Phase: WASTE-7-2015 | Award Amount: 7.65M | Year: 2016

Continuing population and consumption growth are driving global food demand, with agricultural activity increasing to keep pace. Europe has a major agricultural waste problem, generating some 700 million tonnes of waste annually. There is an urgent need and huge opportunity to address the efficient use of agricultural wastes, co-products and by-products (AWCB) towards delivering sustainable value chains in the farming and processing sectors. As such, AgroCycle will convert low value agricultural waste into highly valuable products, achieving a 10% increase in waste recycling and valorisation by 2020. This will be achieved by developing a detailed and holistic understanding of the waste streams and piloting a key number of waste utilisation/valorisation pathways. It will bring technologies and systems from ~TRL4 to ~TRL7 within the 3 years of the project. A post-project commercialisation plan will bring commercially promising technologies/systems to TRL8 and TRL9, ensuring AgroCycle will have an enduring impact by achieving sustainable use of AWCB both inside and outside the agricultural sector, leading to the realisation of a Circular Economy. AgroCycle addresses wastes from several agricultural sectors: wine, olive oil, horticulture, fruit, grassland, swine, dairy and poultry. The AgroCycle consortium is a large (25) multi-national group (including China) comprising the necessary and relevant multi-actors (i.e. researchers; companies in the technical, manufacturing, advisory, retail sectors (Large and SMEs); lead users; end users; and trade/producer associations) for achieving the projects ambitions goals. Farmings unique regional (rural) location means that AgroCycle will help reduce the EUs Innovation Divide and address the Regional Smart Specialisation Strategies for each partner country: impact will be Regional with National and International dimensions. The presence of three partners from China ensures international synergies and a global impact.


Wang W.,Nanjing University of Information Science and Technology | Ni Y.,Nanjing University of Technology | Xu Z.,Nanjing University of Technology
Journal of Alloys and Compounds | Year: 2015

High-reactive facets dominated anatase TiO2 is of great significance to solve environment and energy challenges. Maintaining the pristine structure and improving the photocatalytic activity of TiO2 still need innovation work by employing different modification processes. Here, carbon quantum dots (CQDs) were employed to modify TiO2 with exposed {0 0 1}, {1 0 1}, and {0 1 0} facets by a one-pot hydrothermal method. Results indicate that CQDs can disperse uniformly on TiO2 surface, and the high-reactive facets are maintained perfectly. The introduced CQDs can both enhance the light absorption and suppress photogenerated electron-hole's recombination. Proper amount of introduced CQDs can both significantly enhance the photocatalytic activities, which are very stable, under the UV and visible light irradiation Corresponding photocatalytic mechanisms are also discussed in the present work. © 2014 Elsevier B.V. All rights reserved.


Cai R.,Nanjing University of Technology | Jiang S.,Nanjing University of Technology | Yu X.,Nanjing University of Technology | Zhao B.,Nanjing University of Technology | And 3 more authors.
Journal of Materials Chemistry | Year: 2012

An amenable method for improving rate performance of Li 4Ti 4.85Al 0.15O 12 electrode by post-synthesis treatment in formaldehyde aqueous solution at room temperature is introduced. The as-prepared samples are characterized by XRD, BET, SEM, HR-TEM, XPS and electronic conductivity measurement. The treatment causes no noticeable change on the phase structure and has only little effect on the specific surface area and particulate morphologies. It also only slightly decreases the lithium ion diffusion coefficient. However, it substantially increases the electronic conductivity due to the creation of Ti 3+ in the oxide lattice. The post-synthesis treatment for a period of 4 h effectively increases the capacity at 10 C rate for Li 4Ti 4.85Al 0.15O 12 from 125 mA h g -1 for the untreated sample to 160 mA h g -1, and the electrode performance is also fairly stable. This method is highly attractive for synthesis of high-performance Li 4Ti 5O 12 electrodes owing to its simplicity, energy saving and efficiency. As a general method, post-synthesis treatment using formaldehyde may be applicable to other electrodes. © 2012 The Royal Society of Chemistry.


Zhou Y.,Nanjing University of Technology | Yao Y.-W.,Nanjing University of Technology | Yao Y.-W.,Nanjing Southeast University | Qi Q.,Nanjing Southeast University | And 3 more authors.
Chemical Communications | Year: 2013

Here we present a new approach to aqueous hydrazoic acid detection through the synthesis and evaluation of an alkyne-based fluorescent probe, which could be applied in the monitoring of hydrazoic acid in both living Hela cells and larval zebrafish. This probe can also serve as an early warning automaton which would alert when both azide and protons exist over the threshold value. © 2013 The Royal Society of Chemistry.


Zhao S.,Nanjing University of Technology | Li Y.,Nanjing University of Technology | Li Y.,Nanjing Southeast University | Li D.,Nanjing University of Technology
Microporous and Mesoporous Materials | Year: 2010

In CaO-SiO2-P2O5 system, mesoporous bioactive microspheres with comparatively high P2O5 content (5 mol%-15 mol%) were successfully synthesized by co-templates of non-ionic block copolymer EO20- PO70-EO20 (P123) and cationic surfactant cetyltrimethylammonium bromide (CTAB), followed by hydrothermal and calcination treatment. The structural, morphological and textural properties were investigated by small-angle X-ray diffraction (SAXRD), transmission electron microscope (TEM), scanning electron microscope (SEM), Fourier-transform infrared (FTIR) spectroscope and N2 sorption/desorption techniques. Results showed that the obtained microspheres with a diameter of ∼5 lm exhibit hexagonal ordered and wormlike mesostructures with certain uniformity in size and morphology. This material has BJH pore size of ∼7.3 nm and BET specific surface area of ∼618 m 2/g. Samples with 15 mol% P2O5 induce apatite formation on their surface after soaked in simulated body fluid (SBF) solution for 7 d. The bioactive mesoporous microspheres could be used as a drug carrier for bone repair in future. © 2010 Elsevier Inc. All rights reserved.


Chen X.,Nanjing University of Technology | Guo B.,Nanjing University of Technology | Hu P.,Nanjing University of Technology | Wang Y.,Peking Union Medical College
Electroanalysis | Year: 2014

In this study, a novel non-enzymatic hydrogen peroxide (H2O2) sensor was fabricated based on gold nanoparticles/carbon nanotube/self-doped polyaniline (AuNPs/CNTs/SPAN) hollow spheres modified glassy carbon electrode (GCE). SPAN was in-site polymerized on the surface of SiO2 template, then AuNPs and CNTs were decorated by electrostatic absorption via poly(diallyldimethylammonium chloride). After the SiO2 cores were removed, hollow AuNPs/CNTs/SPAN spheres were obtained and characterized by transmission electron microscopy (TEM), field-emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). The electrochemical catalytic performance of the hollow AuNPs/CNTs/SPAN/GCE for H2O2 detection was evaluated by cyclic voltammetry (CV) and chronoamperometry. Using chronoamperometric method at a constant potential of -0.1V (vs. SCE), the H2O2 sensor displays two linear ranges: one from 5μM to 0.225mM with a sensitivity of 499.82μAmM-1cm-2; another from 0.225mM to 8.825mM with a sensitivity of 152.29μAmM-1cm-2. The detection limit was estimated as 0.4μM (signal-to-noise ratio of 3). The hollow AuNPs/CNTs/SPAN/GCE also demonstrated excellent stability and selectivity against interferences from other electroactive species. The sensor was further applied to determine H2O2 in disinfectant real samples. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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.


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.


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.


Zhao B.,Nanjing University of Technology | Yu X.,Nanjing University of Technology | Cai R.,Nanjing University of Technology | Ran R.,Nanjing University of Technology | And 3 more authors.
Journal of Materials Chemistry | Year: 2012

A facile way for the synthesis of LiFePO 4 composite using a solution combustion technique based on the glycine-nitrate process with inexpensive iron (iii) as the raw material is introduced. Pure phase LiFePO 4 was obtained at an optimal glycine to LiFePO 4 ratio of 4:1. To further increase the electrode performance, sucrose is applied as an organic carbon source. The introduction of sucrose after the auto-combustion is found to be the most effective way in improving electrode performance. The as-synthesized LiFePO 4/C sample contained about 2.86 wt.% carbon shows an attractive discharge capacity of about 160 mA h g -1 at a 0.1 C rate and retains a capacity of 110 mA h g -1 at a 5 C rate. In addition, the electrodes show excellent cycling performance during the 90 cycles at various rates. The rate limiting step for the electrode reaction is explored with the chronoamperometry technique and it demonstrates the surface kinetics is effectively improved for the LiFePO 4 electrode modified with a proper amount of carbon. © 2012 The Royal Society of Chemistry.


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.


Yoriya S.,National Metal and Materials Technology Center | Bao N.,Nanjing University of Technology | Grimes C.A.,Nanjing University of Technology
Journal of Materials Chemistry | Year: 2011

The formation mechanisms of self-organized anodic titania nanotube arrays have been widely studied with an aim towards enabling precise control of nanotube array morphology and properties, thereby allowing control of fabrication parameters for optimal performance of the resulting films in their given application. Building upon recent work [S. Yoriya and C. A. Grimes, J. Mater. Chem., 2011, 21, 102-108], we elucidate the self-ordering and porosity of nanoporous and nanotubular anodic titania films as a function of anodization conditions. © 2011 The Royal Society of Chemistry.


Xiao N.,Nanyang Technological University | Lau D.,Nanyang Technological University | Shi W.,Nanyang Technological University | Zhu J.,Center for Electromobility | And 4 more authors.
Carbon | Year: 2013

We report a simple approach to prepare the nitrogen-modified few-layer graphene (FLG) directly from graphite flakes. With the aid of melamine, graphite flakes can be directly ultrasonicated into FLG in acetone. The subsequent annealing process further transforms the melamine absorbed on the surface of graphene into melon (C6N9H3)x, which is one type of condensation product of melamine, and simultaneously dopes the graphene with nitrogen. When tested as a supercapacitor electrode, the nitrogen-modified FLG shows a much higher specific capacitance (e.g., 227 F/g at 1A/g) than that of reduced graphene oxide (rGO) (e.g., 133 F/g at 1A/g). © 2013 Elsevier Ltd. All rights reserved.


Ma D.,Nanjing University of Technology | Mu W.,Nanjing Sanle Electronic Information Industry Group Co. | Qiu T.,Nanjing University of Technology
Rengong Jingti Xuebao/Journal of Synthetic Crystals | Year: 2013

The effects of B2O3 additive on the sintering and microwave dielectric properties of 0.69CaTiO3-0.31LaAlO3 ceramics prepared by conventional solid-state route were investigated. The results of X-ray diffraction analysis showed that the addition of B2O3 does not change the crystal phase of ceramics. Moderate addition of B2O3 could not only effectively lower sintering temperature and promote the densification but also improve the dielectric properties. The 0.3wt% B2O3-doped 0.69CaTiO3-0.31LaAlO3 ceramic sintered at 1500°C exhibits the optimal dielectric properties: εr≈45.4, Qf≈52800 GHz, τf≈8.78 ppm/°C.


Zhang Y.,Nanjing University of Technology | Zhang Y.,Lulea University of Technology | Ji X.,Lulea University of Technology | Lu X.,Nanjing University of Technology
Applied Energy | Year: 2014

CO2 separation is an energy intensive process, which plays an important role in both energy saving and CO2 capture and storage (CCS) implementation to deal with global warming. To quantitatively investigate the energy consumption of CO2 separation from different CO2 streams and analyze the effect of temperature, pressure and composition on energy consumption, in this work, the theoretical energy consumption of CO2 separation from flue gas, lime kiln gas, biogas and bio-syngas was calculated. The results show that the energy consumption of CO2 separation from flue gas is the highest and that from biogas is the lowest, and the concentration of CO2 is the most important factor affecting the energy consumption when the CO2 concentration is lower than 0.15 in mole fraction. Furthermore, if the CO2 captured from flue gases in CCS was replaced with that from biogases, i.e. bio-CO2, the energy saving would be equivalent to 7.31 million ton standard coal for China and 28.13 million ton standard coal globally, which corresponds to 0.30 billion US$ that can be saved for China and 1.36 billion US$ saved globally. This observation reveals the importance of trading fossil fuel-based CO2 with bio-CO2. © 2014 .


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 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.


Gao F.,Linköping University | Gao F.,University of Cambridge | Tress W.,Linköping 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.


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.


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.


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.


Chen D.,Nanjing University of Technology | Yang G.,Nanjing University of Technology | Ciucci F.,Hong Kong University of Science and Technology | Tade M.O.,Curtin University Australia | And 2 more authors.
Journal of Materials Chemistry A | Year: 2014

Solid oxide fuel cells (SOFCs) as alternatives for energy conversion have the capacity to overcome low energy conversion efficiency, highly detrimental emissions from traditional fuel utilization and the limited reserves of fossil fuels crisis. Herein, a 3D core-shell architecture has been fabricated from solution infiltration in combination with higherature reactive sintering and evaluated as the oxygen reduction electrode for SOFCs. The resultant electrode is composed of a stable porous Sm0.2Ce0.8O1.9 scaffold as the core for bulk oxygen ion diffusion, and a connective Sm,Ce-doped SrCoO3-δ perovskite film as the shell for efficient oxygen reduction reaction and partial current collection. The significant enhancement in conductivity, chemical and thermal compatibility with such core-shell structured electrodes can deliver promising and stable power outputs. An anode-supported solid oxide fuel cell with such a core-shell structured cathode exhibits a peak power density of 1746 mW cm-2 at 750 °C, which is comparable to the most promising cathodes ever developed. In addition, both a symmetrical cell and a fuel cell demonstrate favourable short-term stability during 200 h operation at 700 °C. The combined strategy involving infiltration and higherature reactive sintering (accompanied by ion diffusion) appears to be a promising approach to fabricate cathodes with high electrochemical performance and stability. © 2014 The Royal Society of Chemistry.


Chen C.,Hong Kong University of Science and Technology | Chen D.,Hong Kong University of Science and Technology | Gao Y.,Hong Kong University of Science and Technology | Shao Z.,Nanjing University of Technology | And 2 more authors.
Journal of Materials Chemistry A | Year: 2014

Solid oxide fuel cells (SOFCs) may play a crucial role in solving the energy crisis because they are clean and energy efficient. Finding suitable cathode materials for SOFCs is key to facilitating their widespread use. Besides developing high performance materials, understanding the stability and intrinsic properties of a material is equally important. Herein, Ba 0.95La0.05FeO3-δ (BLF) is studied combining molecular simulations and experiments on single crystal thin films. Lattice dynamics simulations are applied to study the stabilization of barium orthoferrate BaFeO3-δ upon doping with La3+. Simulation results reveal the defect energy for substituting one Ba2+ with La3+ in the cubic phase to be lower than that in the monoclinic phase, contributing to its stabilization. Analogous results are also found by doping the Ba site with Sm3+, Gd3+ and Y3+. In addition, the simulation results suggest that the charge compensation mechanism upon doping is filling oxygen vacancies and La3+ tends to trap the mobile oxygen anions. In turn, as the doping level increases the oxygen anion diffusivity decreases, as is also supported by molecular dynamics simulations. In light of this conclusion, single crystal thin films of La3+ slightly doped BaFeO3-δ, BLF, are grown on yttria-stabilized zirconia substrates using pulsed laser deposition. The polarization resistance of the dense film is 0.07 Ω cm2 at 700 °C in an ambient atmosphere, which is comparable to state-of-the-art Co-based materials. This journal is © the Partner Organisations 2014.


Xu F.,Nanjing Southeast University | Xu F.,Nanjing University of Technology | Dai M.,Nanjing University of Technology | Lu Y.,Nanjing University of Technology | Sun L.,Nanjing Southeast University
Journal of Physical Chemistry C | Year: 2010

We present a two-step synthesis process to produce hierarchical ZnO nanoarchitectures that involves the preparation of ZnO nanosheet arrays by the pyrolysis of the precursor Zn5(OH)8Cl2 electrodeposited on conductive glass substrates, followed by the aqueous chemical growth (ACG) of dense ZnO single-crystalline nanowires on the surfaces of the primary ZnO nanosheets. The dye-sensitized solar cell (DSSC) based on the hierarchical ZnO nanowire-nanosheet architectures showed a power conversion efficiency of 4.8%, which is nearly twice as high as that of the DSSC constructed using a photoanode of bare ZnO nanosheet arrays. The better photovoltaic performance of hierarchical ZnO nanoarchitecture DSSC was due to a better dye loading and light harvesting as a consequence of the enlargement of the internal surface area within the photoanode. Moreover, the improved performance for the DSSC with the hierarchical ZnO nanowire-nanosheet architectures may be also ascribed to more light scattering behavior through extending the optical path length within the photoanode so as to increase the light harvesting. The results demonstrate potential application of the hierarchical ZnO nanoarchitectures derived from ZnO nanosheet arrays for highly efficient DSSCs. © 2010 American Chemical Society.


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 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.


Xu F.,Nanjing Southeast University | Sun L.,Nanjing Southeast University | Dai M.,Nanjing University of Technology | Lu Y.,Nanjing University of Technology
Journal of Physical Chemistry C | Year: 2010

Novel rhombus-like ZnO nanorod (NR) arrays were achieved via a facile two-step synthesis strategy based on first a low-temperature aqueous electrodeposition of vertically aligned rhombic ZnFOH NR arrays in the presence of fluoride and second a pyrolysis of ZnFOH intermediate into ZnO with the same morphology. The fluorine-ion-mediated electrodeposition mechanism of ZnFOH was confirmed for the first time, and the proposed formation process that the rhombus-like ZnO NRs characterized by mesoporous structure derived from the electrodeposited ZnFOH intermediate was corroborated by systematic structural characterization of the as-prepared products. A dye-sensitized solar cell (DSSC) based on the rhombus-like ZnO NR arrays with a larger surface roughness factor was assembled, and a higher conversion efficiency of 0.69% was attained in comparison to 0.47% of the DSSC based on the hexagon-like ZnO NR arrays electrodeposited in the absence of fluoride. Further, we demonstrate that the unique two-step synthesis strategy also possessed the capability of constructing complex nanoarchitectures with 1D rhombus-like ZnO NRs as the building blocks. © 2010 American Chemical Society.


Zhu H.,Nanjing University of Technology | Wang W.,Nanjing University of Technology | Ran R.,Nanjing University of Technology | Shao Z.,Nanjing University of Technology | Shao Z.,Monash University
International Journal of Hydrogen Energy | Year: 2013

Various Ni-LaxCe1-xOy composites were synthesized and their catalytic activity, catalytic stability and carbon deposition properties for steam reforming of methane were investigated. Among the catalysts, Ni-La0.1Ce0.9Oy showed the highest catalytic performance and also the best coking resistance. The Ni-LaxCe1-xOy catalysts with a higher Ni content were further sintered at 1400 °C and investigated as anodes of solid oxide fuel cells for operating on methane fuel. The Ni-La0.1Ce 0.9Oy anode presented the best catalytic activity and coking resistance in the various Ni-LaxCe1-xOy catalysts with different ceria contents. In addition, the Ni-La 0.1Ce0.9Oy also showed improved coking resistance over a Ni-SDC cermet anode due to its improved surface acidity. A fuel cell with a Ni-La0.1Ce0.9Oy anode and a catalyst yielded a peak power density of 850 mW cm-2 at 650 °C while operating on a CH4-H2O gas mixture, which was only slightly lower than that obtained while operating on hydrogen fuel. No obvious carbon deposition or nickel aggregation was observed on the Ni-La 0.1Ce0.9Oy anode after the operation on methane. Such remarkable performances suggest that nickel and La-doped CeO 2 composites are attractive anodes for direct hydrocarbon SOFCs and might also be used as catalysts for the steam reforming of hydrocarbons.© 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd.


Chen D.,Hong Kong University of Science and Technology | Chen C.,Hong Kong University of Science and Technology | Dong F.,Nanjing University of Technology | Shao Z.,Nanjing University of Technology | Ciucci F.,Hong Kong University of Science and Technology
Journal of Power Sources | Year: 2014

Ba0.95La0.05FeO3-δ (BLF) thin films as electrodes for intermediate-temperature solid oxide fuel cells are prepared on single-crystal yttria-stabilized zirconia (YSZ) substrates by pulsed laser deposition. The phase structure, surface morphology and roughness of the BLF thin films are characterized by X-ray diffraction, scanning electron microscopy and atomic force microscopy. X-ray photoelectron spectroscopy is used to analyze the compositions of the deposited thin film and the chemical state of transition metal. The dense thin film exhibits a polycrystalline perovskite structure with a low surface roughness and a high oxygen vacancy concentration on the surface. Ag (paste or strip) and Au (strip) are applied on both surfaces of the symmetric cells as current collectors to evaluate electrochemical performance of the thin films. The electrode polarization resistances of the symmetric cells are found to be lower than those of most cobalt-free thin-film electrodes, e.g., 0.437 Ω cm2 at 700 C and 0.21 atm. The oxygen reduction reaction mechanism of the BLF cathode in symmetric cells is studied by electrochemical impedance spectroscopy thanks to the equivalent fitting analysis. Both the oxygen surface exchange reaction and charge transfer are shown to determine the overall oxygen reduction reaction. © 2013 Elsevier B.V. All rights reserved.


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.


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.


Yao Y.-W.,Nanjing Southeast University | Zhou Y.,Nanjing University of Technology | Lin B.-P.,Nanjing Southeast University | Yao C.,Nanjing University of Technology
Tetrahedron Letters | Year: 2013

A novel and metal free catalysis of synthesizing 5-substituted 1H-tetrazoles through 1,3-dipolar cycloaddition of boron-azides and nitriles is reported with broad substrate scope and excellent yields. © 2013 Elsevier Ltd. All rights reserved.


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.


Du Y.,Nanjing University of Technology | Chen R.Z.,Nanjing University of Technology | Yao J.F.,Monash University | Wang H.T.,Monash University
Journal of Alloys and Compounds | Year: 2013

In this work, porous ZnO photocatalysts were attempted to be prepared by a facile method, i.e. the thermal treatment of zeolitic imidazolate framework-8, and then characterized using X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR) spectroscopy and nitrogen adsorption-desorption. It was found that the calcination temperature and time significantly influenced the morphology, composition and pore structure of ZnO. The photocatalytic activities of as-prepared ZnO powders were evaluated in the degradation of methylene blue (MB) under UV light in comparison with commercial anatase TiO2 and Degussa P25 TiO2. The surface area and crystallinity of porous ZnO obviously affected the photocatalytic activity of ZnO. The ZnO prepared at 500 °C for 5 h (ZnO-500-5) showed the highest photocatalytic activity, which was higher than that of the commercial anatase TiO2 and lower than that of Degussa P25 TiO2. © 2012 Elsevier B.V. All rights reserved.


Gao Y.,Hong Kong University of Science and Technology | Chen D.,Hong Kong University of Science and Technology | Chen C.,Hong Kong University of Science and Technology | Shao Z.,Nanjing University of Technology | And 2 more authors.
Journal of Power Sources | Year: 2015

Oriented PrBaCo2O5+δ (PBC) thin films are prepared on yttria-stabilized ZrO2 (YSZ) substrates with orientations (001), (110) and (111) via pulsed laser deposition (PLD). Electrochemical impedance spectroscopy (EIS) experiments at various temperatures and oxygen partial pressures reveal a good oxygen reduction reaction (ORR) performance of all the thin films. However, the films' performance has considerable variance. PBC thin film deposited on (111) oriented YSZ had the best performance, followed by (110) and (001). Experiments including high resolution X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and computation, namely molecular dynamics (MD), are used to elucidate the substrate-determined orientations, examine the morphology and composition of the thin films, and to explain the variance of the ORR performance. Our results support the anisotropy of the oxygen vacancy pathway in the a-b plane and indicate that the substrate orientations can have great influence on the thin films properties. © 2014 Elsevier B.V. All rights reserved.


He G.,Nanjing University of Technology | Zhao L.,Nanjing University of Technology | Chen K.,Nanjing University of Technology | Liu Y.,Nanjing Southeast University | Zhu H.,Nanjing University of Technology
Talanta | Year: 2013

A rapid, simple and real-time colorimetric assay for detecting phosphate anions (PO4 3-) in aqueous solution was developed. The method was based on a novel functionalized gold nanoparticles (MPTP-Zn-AuNPs), which was synthesized by the ligand-exchange reaction of 4′-(4- mercaptophenyl)-2,2′:6′,2″-terpyridine zinc(II) complex (MPTP-Zn) with citrate-stabilized aqueous AuNPs. The strong coordination between MPTP-Zn-AuNPs and PO4 3- anion gave rise to a color change from wine-red to blue-gray that was discernible by the naked eye and an easily measurable alteration in the absorption spectrum of the particles in aqueous solution. And the new technique exhibited the high selectivity for PO 4 3- over 11 other anions and could be used to determine PO4 3- with a detection limit of 11 ppm. © 2012 Elsevier B.V.


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.


Chen Y.,Nanjing University of Technology | Zhou W.,Nanjing University of Technology | Ding D.,Georgia Institute of Technology | Liu M.,Georgia Institute of Technology | And 4 more authors.
Advanced Energy Materials | Year: 2015

Solid oxide fuel cells (SOFCs) represent one of the cleanest and most efficient options for the direct conversion of a wide variety of fuels to electricity. For example, SOFCs powered by natural gas are ideally suited for distributed power generation. However, the commercialization of SOFC technologies hinges on breakthroughs in materials development to dramatically reduce the cost while enhancing performance and durability. One of the critical obstacles to achieving high-performance SOFC systems is the cathodes for oxygen reduction reaction (ORR), which perform poorly at low temperatures and degrade over time under operating conditions. Here a comprehensive review of the latest advances in the development of SOFC cathodes is presented: complex oxides without alkaline earth metal elements (because these elements could be vulnerable to phase segregation and contaminant poisoning). Various strategies are discussed for enhancing ORR activity while minimizing the effect of contaminant on electrode durability. Furthermore, some of the critical challenges are briefly highlighted and the prospects for future-generation SOFC cathodes are discussed. A good understanding of the latest advances and remaining challenges in searching for highly active SOFC cathodes with robust tolerance to contaminants may provide useful guidance for the rational design of new materials and structures for commercially viable SOFC technologies. Recent advances in the development of cathode materials for solid oxide fuel cells (SOFCs) are reviewed, focusing on the relationship between crystal structure, composition, catalytic activity, and durability. Various strategies for microstructure optimization and performance enhancement are highlighted, together with challenges and prospects, to provide guidelines for knowledge-based design of novel cathodes for a new generation of SOFCs. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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

Herein we report the proof-of-principle of a new concept of rechargeable batteries based on chloride shuttle, i.e., chloride ion batteries. This system includes the metal chloride/metal electrochemical couple and an electrolyte composed of binary ionic liquids allowing chloride ion transfer at room temperature. © 2013 Elsevier B.V. All rights reserved.


Xu F.,Nanjing University of Technology | Xu F.,Nanjing Southeast University | Lu Y.,Nanjing University of Technology | Sun L.,Nanjing Southeast University | Zhi L.,CAS National Center for Nanoscience and Technology
Chemical Communications | Year: 2010

A facile scalable two-step approach based on a low-temperature aqueous electrodeposition and a solid-state crystal phase transformation process was developed to grow rhombus-shaped ZnO nanorod arrays which showed markedly improved hydrogen storage capacity. © The Royal Society of Chemistry 2010.


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.


Kao H.,Nanjing University of Technology | Li M.,Nanjing Southeast University | Lv X.,Nanjing University of Technology | Tan J.,Nanjing Southeast University
Journal of Thermal Analysis and Calorimetry | Year: 2012

Expanded graphite (EG)/paraffin/organic montmorillonite (OMMT) composite phase change material (PCM) was prepared by using melt intercalation method. The microstructure of EG/paraffin/OMMT is observed by scanning electron microscope (SEM). The thermal properties are investigated by differential scanning calorimetry (DSC). The mass loss of EG/paraffin/OMMT after 50 heating cycles was measured for investigating the influence of EG and OMMT on the thermal properties of paraffin. The results show that EG and OMMT have the ability of adsorption and shape-stability. The melting point EG/paraffin/OMMT is decreased slightly with an addition of paraffin and the latent heat of EG/paraffin/OMMT is determined by the mass ratio of paraffin. The heat transfer efficiency of EG/paraffin/OMMT is strengthened and the heating time is decreased to one-sixth of that of paraffin by addition of EG and OMMT. The thermal stability of EG/paraffin/OMMT is improved by addition of OMMT. © 2011 Akadémiai Kiadó, Budapest, Hungary.


Chen D.,Hong Kong University of Science and Technology | Chen D.,Jinan University | Chen C.,Hong Kong University of Science and Technology | Baiyee Z.M.,Hong Kong University of Science and Technology | And 3 more authors.
Chemical Reviews | Year: 2015

The recent advances in the development of nonstoichiometric oxides, ranging from simple oxide, perovskite, layered perovskite, and pyrochlore, for oxygen reduction Reaction (ORR) and oxygen evolution reaction (OER) in metal-air batteries (MABs) and low-temperature fuel cells (LTFCs) are reviewed. These catalysts are characterized to be low cost and earth-abundant, as well as possess relatively high activity and stability under operation conditions. It is expected that these catalysts will be essential to the future development of multiple technologies. It is expected that the development of nonstoichiometric oxides, with the mutual development of system components, will lead to highly stable and efficient MABs and LTFCs in practical applications in the near future. The electrochemical strain microscopy technique may provide a direct visualization of the ORR/OER activation process on the scale of several nanometers and provide nanoscale understanding into local kinetics. An efficient approach to discover new materials with high intrinsic activities is to tune the electronic structure of existing materials.


Zhang X.,University of Alabama | Zhang X.,Nanjing Southeast University | Bao N.,Nanjing University of Technology | Ramasamy K.,University of Alabama | And 4 more authors.
Chemical Communications | Year: 2012

Cu 2FeSnS 4 (CFTS) nanocrystals with tunable crystal phase have been synthesized using a solution-based method. As-synthesized CFTS nanocrystals in the shape of oblate spheroid and triangular plate with band gaps of 1.54 ± 0.04 and 1.46 ± 0.03 eV, respectively, appear attractive as a low-cost substitute for thin film solar cells. © The Royal Society of Chemistry 2012.


Wang Y.,Nanjing University of Technology | Tong L.,Nanjing University of Technology | Steinhart M.,University of Osnabrück
ACS Nano | Year: 2011

Nanoscopic domain structures of BCP nanorods can be converted into well-defined mesopore systems by swelling the BCP minority component with a selective solvent at temperatures below the bulk glass transition temperature of the nonswelling matrix. The initial stage of this process involves rapid morphology reconstruction of the nonswelling majority domains to accommodate the increased volume of the swelling minority domains caused by rapid solvent uptake. Morphology reconstruction slows down once entropic restoring forces of the swelling chains impede further uptake of swelling agent. Upon evaporation of the swelling agent, mesopores form in place of the swollen domains as the swollen minority blocks undergo entropic relaxation while intermediate nonequilibrium morphologies in the BCP nanorods are fixated by the reconstructed majority component. The surface area of mesopores developing when swollen cylindrical minority domains collapse may be minimized by the growth of Rayleigh instabilities. Depending on swelling temperature, swelling agent, and BCP architecture, BCP nanorods with one or several cylindrical channels undulated or uniform in diameter running along their long axes, linear strings of spherical cavities, and continuous mesopore systems can be obtained. © 2011 American Chemical Society.


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.


Chen D.,Hong Kong University of Science and Technology | Yang G.,Nanjing University of Technology | Shao Z.,Nanjing University of Technology | Ciucci F.,Hong Kong University of Science and Technology
Electrochemistry Communications | Year: 2013

A dense and crack-free nanoscaled Sm-doped CeO2 (SDC) thin film as a buffer layer for intermediate-temperature solid oxide fuel cells has been successfully deposited onto the polycrystalline yttria-stabilized zirconia (YSZ) electrolyte by pulsed laser deposition (PLD). SEM and XRD results reveal that the dense and crack-free buffer layer effectively prevents the formation of the insulating layer between the Ba0.5Sr0.5Co 0.8Fe0.2O3 - δ (BSCF) cathode and the YSZ electrolyte. The fuel cell with the as-deposited buffer layer exhibits high peak power density (e.g., 2016 mW cm- 2 at 700 C) and low resistance. In contrast, at 700 C the fuel cell with an optimized SDC layer prepared by spray deposition or the fuel cell without interlayer have lower peak power densities, 1132 mW cm- 2 and 60 mW cm- 2 respectively, and higher resistances. The significant enhancement in peak power densities with the adoption of the SDC buffer layer by PLD is likely due to the combination of three factors: the lack of solid-state reaction between BSCF and YSZ, the thinner thickness in comparison to the SDC layer by spray deposition, as well as the improvement of the charge-transfer process. © 2013 Elsevier B.V.


Duan H.-B.,Nanjing University of Technology | Ren X.-M.,Nanjing University of Technology | Ren X.-M.,Coordination Chemistry Institute | Meng Q.-J.,Coordination Chemistry Institute
Coordination Chemistry Reviews | Year: 2010

1D spin-Peierls-like complexes assembled from [Ni(mnt)2]- with Λ-shaped 1-(4′-R-benzyl)pyridinium derivatives (R represents a substituent) are reviewed, with data on their crystal structures, magnetic properties under ambient conditions as well as under pressure, and the nature of the paramagnetic-to-nonmagnetic transition. In this series of 1D spin systems, the correlation between the magnetic exchange and the anion stacking pattern is addressed by application of density functional theory (DFT) combined with a broken-symmetry approach. The qualitative relationship between the transition enthalpy change and the variation of the magnetic susceptibility in the low-temperature phase is determined. The influence of nonmagnetic doping on the structural and magnetic properties and the magnetic transitions are reported. Furthermore, the effect of the substituent group in the phenyl ring of the cation on the transition temperature and the origin of the transition are discussed. © 2009 Elsevier B.V. All rights reserved.


Xu F.,Nanjing Southeast University | Shen Y.,Nanjing Southeast University | Sun L.,Nanjing Southeast University | Zeng H.,Japan International Center for Materials Nanoarchitectonics | Lu Y.,Nanjing University of Technology
Nanoscale | Year: 2011

A hierarchical ZnO nanoplate-nanowire (ZNP-ZNW) architecture immobilized onto a substrate via a facile two-step synthesis strategy was used as an environmentally safe and recyclable photocatalyst. It showed greatly enhanced photocatalytic activity compared with a monomorphological ZnO nanoplate structure in the degradation of methyl orange (MO). The higher content of surface oxygen defects, which can capture the photogenerated electrons and holes separately and make them available for decomposing organic contaminants, is considered to play an important role in the degradation of MO and makes a major contribution to the enhanced photocatalysis. Increasing the surface-to-volume (S/V) ratio without limit cannot benefit the photocatalytic activity significantly if there are not enough defects to separate additional photogenerated charges caused by a larger S/V ratio. A detailed photocatalytic mechanism related to surface defects of the hierarchical architecture was clearly demonstrated. The present study provides a new paradigm for further understanding the photocatalytic mechanism and suggests a new direction to design high-efficiency photocatalysts based on increasing the number of surface defects of nanostructures. © 2011 The Royal Society of Chemistry.


Wang W.,Nanjing University of Technology | Su C.,Curtin University Australia | Wu Y.,Monash University | Ran R.,Nanjing University of Technology | Shao Z.,Nanjing University of Technology
Chemical Reviews | Year: 2013

The article examines progress in solid oxide fuel cells with nickel-based anodes operating on methane and related fuels. Natural gas has already been widely used as an important energy source in numerous applications, including the heating of buildings and cooking by direct combustion, the generation of electricity by gas turbines or steam turbines, and as a fuel for combustion engines in vehicles. Conventional SOFCs employ nickel-based cermet anodes, which exhibit good compatibility with electrolytes composed of stabilized zirconia or doped ceria, high activity toward the electrocatalytic oxidation of hydrogen, and high electronic conductivity. By direct feeding of a nickel cermet anode-based SOFC with methane, the anode may play dual roles: catalyzing the methane reforming reactions and promoting the electrochemical oxidation of hydrogen, carbon monoxide, and methane.


News Article | November 10, 2016
Site: www.marketwired.com

OAKVILLE, ONTARIO--(Marketwired - Nov. 10, 2016) - Saint Jean Carbon Inc. ("Saint Jean" or the "Company") (TSX VENTURE:SJL), a carbon science company engaged in the exploration of natural graphite properties and related carbon products, is pleased to announce that the Company has a new Chief Technology Officer (CTO), Dr. Zhongwei Chen PhD, MSChE, BS, Canadian Research Chair and Professor in Advanced Materials for Clean Energy Waterloo Institute for Nanotechnology Department of Chemical Engineering, University of Waterloo. Dr. Zhongwei Chen will lead the technology planning, engineering and implementation of all of the Company's clean energy storage and energy creation initiatives. Dr. Zhongwei Chen's research work covers advanced materials and electrodes for PEM fuel cells, lithium ion batteries and zinc-air batteries. His education; PhD, University of California - Riverside, MSChE, East China University of Science and Technology, China, BS, Nanjing University of Technology, China. His honours and awards; Early Researcher Award, Ministry of Economic Development and Innovation, Ontario, Canada (2012), NSERC Discovery Accelerator Award (2014), Canada Research Chair in Advanced Materials for Clean Energy (2014), and E.W.R Steacie Memorial Fellowship (2016). Please follow the link to the full website for complete in-depth details. http://chemeng.uwaterloo.ca/zchen/index.html Dr. Zhongwei Chen, CTO, commented: "I have had the opportunity to work very closely with Saint Jean Carbon over the last year, specifically with their advanced spherical coated graphite for lithium-ion batteries and the very promising results have me hopeful that we, together with my global partners, will build the best and most advanced graphite electrode materials for the growing electric car and mass energy storage industries. We feel it is imperative to make sure that in every step we take towards future supply, we demonstrate our team strengths and constant superior technological advancements." Paul Ogilvie, CEO, commented: "On behalf of the Board of Directors, Shareholders and Stakeholders, I am honoured that Zhongwei has chosen our Company, over the hundreds of other possible suitors. We feel our working relationship over the last year has proven a very strong bond between our raw material and his engineering excellence. We are in a constant drive to move forward as fast as we can with the very best people, and with this appointment, we have just topped our own expectations." Saint Jean is a publicly traded carbon science company, with interest in graphite mining claims in the province of Quebec in Canada. For the latest information on Saint Jean's properties and news please refer to the website: http://www.saintjeancarbon.com/ On behalf of the Board of Directors Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release. FORWARD LOOKING STATEMENTS: This news release contains forward-looking statements, within the meaning of applicable securities legislation, concerning Saint Jean's business and affairs. In certain cases, forward-looking statements can be identified by the use of words such as "plans", "expects" or "does not expect", "intends" "budget", "scheduled", "estimates", "forecasts", "intends", "anticipates" or variations of such words and phrases or state that certain actions, events or results "may", "could", "would", "might" or "will be taken", "occur" or "be achieved". These forward-looking statements are based on current expectations, and are naturally subject to uncertainty and changes in circumstances that may cause actual results to differ materially. The forward-looking statements in this news release assume, inter alia, that the conditions for completion of the Transaction, including regulatory and shareholder approvals, if necessary, will be met. Although Saint Jean believes that the expectations represented in such forward-looking statements are reasonable, there can be no assurance that these expectations will prove to be correct. Statements of past performance should not be construed as an indication of future performance. Forward-looking statements involve significant risks and uncertainties, should not be read as guarantees of future performance or results, and will not necessarily be accurate indications of whether or not such results will be achieved. A number of factors, including those discussed above, could cause actual results to differ materially from the results discussed in the forward-looking statements. Any such forward-looking statements are expressly qualified in their entirety by this cautionary statement. All of the forward-looking statements made in this press release are qualified by these cautionary statements. Readers are cautioned not to place undue reliance on such forward-looking statements. Forward-looking information is provided as of the date of this press release, and Saint Jean assumes no obligation to update or revise them to reflect new events or circumstances, except as may be required under applicable securities laws.


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.


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.


Ma W.,Tsinghua University | Wang X.,Tsinghua University | Zhang J.,Nanjing University of Technology
Journal of Polymer Science, Part B: Polymer Physics | Year: 2010

The crystallization and melting behaviors of poly (vinylidene fluoride) (PVDF) with small amount of nanoparticles (1 wt %), such as montmorillonite (MMT), SiO2, CaCO3, or polytetrafluoroethylene (PTFE), directly prepared by melt-mixing method were investigated by scanning electron microscopy (SEM), polarizing optical microscopy, Fourier transform infrared spectroscopy, wide angle X-ray diffraction (WAXD), and differential scanning calorimetry (DSC). The nanoparticle structure and the interactions between PVDF molecule and nanoparticle surface predominated the crystallization behavior and morphology of the PVDF. Small amount addition of these four types of nanoparticles would not affect the original crystalline phase obtained in the neat PVDF sample (a phase), but accelerated the crystallization rate because of the nucleation effect. In these four blend systems, MMT or PTFE nanoparticles could be well applied for PVDF nanocomposite preparation because of stronger interactions between particle surface and PVDF molecules. The nucleation enhancement and the growth rate of the spherulites were decreased in the order SiO2 > CaCO3 > PTFE > MMT. The melting and recrystallization of PVDF was found in MMT addition sample, because of the special ways of ordering of the PVDF chains. © 2010 Wiley Periodicals, Inc.


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.


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.


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.


Shen L.,University of Alabama | Bao N.,Nanjing University of Technology | Zhou Z.,University of Alabama | Prevelige P.E.,University of Alabama at Birmingham | Gupta A.,University of Alabama
Journal of Materials Chemistry | Year: 2011

A variety of inorganic materials with amazingly complex structures and morphologies are produced by natural organisms. The fundamental mechanism underlying the natural biological synthesis of inorganic materials can be ascribed to the unique recognition and interaction of proteins with specific inorganic species. By mimicking natural biomineralization, genetically engineered proteins have in recent years been successfully utilized as platforms for the synthesis of inorganic nanostructures of various compositions under mild reaction conditions. Moreover, the precisely oriented assembly of genetically engineered proteins offers flexibility in designing inorganic nanostructures with desired complex architecture. This short review summarizes the recent progress in materials design using genetically engineered protein templates. © 2011 The Royal Society of Chemistry.


Cheng J.,Nanjing University of Technology | Zhang J.,Nanjing University of Technology | Wang X.,Tsinghua University
Journal of Applied Polymer Science | Year: 2013

Ternary blends composed of matrix polymer poly(vinylidene fluoride) (PVDF) with different proportions of poly(methyl methacrylate) (PMMA)/poly(vinyl pyrrolidone) (PVP) blends were prepared by solution casting. The crystallization behavior and hydrophilicity of ternary blends were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), and contact angle test. According to morphological analysis, the surface was full of typical spherulitic structure of PVDF and the average diameter was in the order of 3 μm. The samples presented predominantly β phase of PVDF by solution casting. It indicated that the size of surface spherulites and crystalline phase had little change with the PMMA or PVP addition. Moreover, FTIR demonstrated special interactions among the ternary polymers, which led to the shift of the carbonyl stretching absorption band of PVP. On the other hand, the melting, crystallization temperature, and crystallinity of the blends had a little change compared with the neat PVDF in the first heating process. Except for the content of PVP containing 30 wt %, the crystallinity of PVDF decreased remarkably from 64% to 33% and the value of t1/2 was not obtained. Besides, the hydrophilicity of PVDF was remarkably improved by blending with PMMA/PVP, especially when the content of PVP reached 30 wt %, the water contact angle displayed the lowest value which decreased from 98.8° to 51.0°. Copyright © 2012 Wiley Periodicals, Inc.


Ma W.,Tsinghua University | Zhang J.,Nanjing University of Technology | Bruggen B.V.D.,k-Technology | Wang X.,Tsinghua University
Journal of Applied Polymer Science | Year: 2013

Novel microporous membranes were prepared via thermally induced solid-liquid (S-L) phase separation of mixtures containing poly(vinylidene fluoride) (PVDF)/diphenyl ketone (DPK)/nanoparticles [such as montmorillonite (MMT) and polytetrafluoroethylene (PTFE)] in diluted systems with a mass ratio of 29.7/70/0.3 wt %. The crystallization and melting characteristics of these diluted systems were investigated by polarizing optical microscopy (POM), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and wide angle X-ray diffraction (WAXD). The nanoparticle structure and the interaction between PVDF chains and nanoparticle surfaces determined the crystallization behavior and morphology of the PVDF membrane. The addition of MMT and PTFE had a significant nucleation enhancement on the crystallization of PVDF accompanied by S-L phase separation during the thermally induced phase separation (TIPS) process. It was observed that an interconnected lamellar structure was formed in these two membranes, leading to a higher tensile strength compared with that of the reference membrane without nanoparticles addition. Additionally, addition of MMT facilitates the fiber-like β phase crystal formation, resulting in the highest elongation at break. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 Copyright © 2012 Wiley Periodicals, Inc.


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.


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.


Liu J.-C.,Nanjing University of Technology | Lei G.-H.,Hohai University | Zheng M.-X.,East China Jiaotong University
Geotextiles and Geomembranes | Year: 2014

A quasi-analytical method is newly introduced to solve the equal-strain consolidation problem of multilayered soil with a vertical drain system. Both vertical and radial drainage conditions are considered, together with the effects of drain resistance and smear. By using the method of Laplace transform with respect to time, a general explicit analytical solution for the consolidation in transformed space is obtained. Numerical inversion of the Laplace transform in the time domain is then applied to obtain the solution for calculating excess pore-water pressure. This solution is explicitly expressed and conveniently coded into a computer program for ease and efficiency of practical use. Its validity and accuracy are verified by comparing the special cases of the proposed solution with a finite-element solution and an available analytical solution. Moreover, the consolidation behavior of a four-layered soil with a vertical drain is investigated. The order of soil layers is shown to have a significant effect on the behavior of consolidation. This highlights that caution should be exercised when weighted average consolidation parameters of multilayered soil are used to analyze the consolidation behavior. © 2014 Elsevier Ltd.


Wang Y.,Hohai University | Jin S.,Hohai University | Wang Q.,Hohai University | Lu G.,Hohai University | And 2 more authors.
Journal of Chromatography A | Year: 2013

A novel micro-solid-phase extraction (μ-SPE) device coupled with ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS) was established to determine five typical estrogens in aqueous samples. Zeolitic imidazolate framework-8 (ZIF-8) as sorbent was packed in polypropylene membrane to construct the μ-SPE device. Important extraction parameters including extraction time, extraction temperature, desorption solvent, desorption time and sample pH were carefully optimized to improve the extraction efficiency of the μ-SPE device. ZIF-8 sorbent showed an exceptional chemical stability and extraction efficiency for estrogens. In theory, the high extraction efficiencies may be due to the coordination bonding, intermolecular π-π interactions and hydrophobic interactions between ZIF-8 and the estrogens. Under the most favorable extraction conditions, for estrogens in aqueous samples, the proposed method provided low limits of detection (0.05-0.1 μg/L), wide linearity range (three orders), excellent correlation coefficients (0.959-0.999) and satisfactory measurement precision (4.9-9.2%). which can meet the demand of determining estrogens at the trace level. Finally, the proposed method was successfully applied to determine the estrogens in real sewage water samples. © 2013 Elsevier B.V.


Jiang W.,China University of Petroleum - East China | Liu Z.,Jilin University | Gong J.M.,Nanjing University of Technology | Tu S.T.,Nanjing University of Technology
International Journal of Pressure Vessels and Piping | Year: 2010

Clad plates are widely used in the construction of corrosion resistant equipment. During the repair of clad plates, residual stresses are generated and influence the structure integrity. This paper uses the finite element method (FEM) to predict the residual stresses in a repair weld of a stainless steel clad plate. The effect of repair width on residual stresses has also been investigated by numerical simulation. Due to the material mismatching between clad metal and base metal, a discontinuous stress distribution has been generated across the interface between clad and base metals. The peak residual stress occurs in the heat affected zone (HAZ) of the base metal, because the yield strength of the base metal is larger than that of the clad metal. With an increase in repair width, the residual stresses are decreased. When the repair width is increased to 24 mm, the residual stresses in the weld have been decreased greatly and the peak residual stresses have been reduced to less than the yield strength. Therefore, the recommended repair width should not be less than 24 mm, which provides a reference for optimizing repair welding technology for this stainless steel clad pate. © 2010 Elsevier Ltd.


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.


Patent
Nanjing University of Technology and Zhejiang Medicine Co. | Date: 2012-12-10

Disclosed is a preparation method of the lycopene intermediate 3-methyl-4,4-dialkoxy-1-butaldehyde. The preparation method comprises the following steps: (1) reacting 2-methyl-3,3-dialkoxy-1-halopropane with magnesium powder in the solvent of anhydrous tetrahydrofuran at a temperature of 4565 C. to generate a mixture of Grignard reagents under the protection of an inert gas; and (2) adding N,N-disubstituted carboxamide to the mixture of Grignard reagents and reacting at a temperature of 10 C.35 C. to obtain 3-methyl-4,4-dialkoxy-1-butaldehyde. The process route of the present invention is simple and direct, the operation is easy, the conditions are mild and the yield is good, and thus the invention has commercial value.


Patent
Nanjing University of Technology and Zhejiang Medicine Co. | Date: 2014-11-05

Provided in the present invention is a method for synthesizing 2,7-dimethyl-2,4,6-octatriene-1,8-dialdehyde. The synthesis method comprises the following steps: (1) adding acetaldehyde diethyl acetal and ethyl-(1-propenyl)-ether under the effect of a catalyst to produce 1,1,3-triethoxy-2-methyl-butane; (2) pyrolysis synthesizing 1,1,3-triethoxy-2-methyl-butane under the catalytic effects of isoquinoline and p-Toluenesulfonic acid to produce 1-methoxy-2-methyl-1,3-butadiene; (3) dissolving 1-methoxy-2-methyl-1,3-butadiene in anhydrous ethanol solvent for synthesis with a phase transfer catalyst, cetyl-trimethyl ammonium bromide, and a chlorinating agent, trichloroisocyanuric acid, to generate 4,4-diethoxy-3-methyl-1- chloro-butene; (4) combining 4,4-diethoxy-3-methyl-1-chloro-butene with a triphenylphosphine salt to produce a phosphonium salt; and (5) condensing the phosphonium salt under the effects of hydrogen peroxide in conjunction with sodium carbonate solution to generate 1,1,8,8-tetramethyl-2,7-dimethyl-2,4,6-octatriene; then hydrolyzing under acidic conditions to synthesize 2,7-dimethyl-2,4,6-octatriene-1,8- dialdehyde. The present invention has a simple process route, is easy to operate, and has mild conditions, great yield, and great industrial value.


Patent
Nanjing University of Technology and Zhejiang Medicine Co. | Date: 2014-11-05

Provided in the present invention is a preparation method for a phosphonic salt, comprising the step of: reacting 3,7,11-trimethyldodec-1,4,6,10-tetraene-3-ol with triarylphosphine and an acid in an alcohol solvent at 50-100C to form the phosphonic salt, wherein the acid is a sulfamic acid or methanesulfonic acid, and the alcohol solvent is a straight chain monohydric alcohol containing 1-5 carbon atoms. The method is performed in nearly neutral conditions, greatly reducing the generation of impurities and greatly obtaining phosphonic salt with an increased E content. The yield of lycopene obtained by using the phosphonic salt as a raw material is high.


Patent
Nanjing University of Technology and Zhejiang Medicine Co. | Date: 2014-11-05

Disclosed is a preparation method of the lycopene intermediate 3-methyl-4,4-dialkoxy-1-butaldehyde. The preparation method comprises the following steps: (1) reacting 2-methyl-3,3-dialkoxy-1-halopropane with magnesium powder in the solvent of anhydrous tetrahydrofuran at a temperature of 45~65C to generate a mixture of Grignard reagents under the protection of an inert gas; and (2) adding N,N-disubstituted carboxamide to the mixture of Grignard reagents and reacting at a temperature of 10C~35C to obtain 3-methyl-4,4-dialkoxy-1-butaldehyde. The process route of the present invention is simple and direct, the operation is easy, the conditions are mild and the yield is good, and thus the invention has commercial value.


Patent
Nanjing University of Technology and Zhejiang Medicine Co. | Date: 2012-12-10

Provided in the present invention is a preparation method for a phosphonic salt, comprising the step of: reacting 3,7,11-trimethyldodec-1,4,6,10-tetraene-3-ol with triarylphosphine and an acid in an alcohol solvent at 50-100 C. to form the phosphonic salt, wherein the acid is a sulfamic acid or methanesulfonic acid, and the alcohol solvent is a straight chain monohydric alcohol containing 1-5 carbon atoms. The method is performed in nearly neutral conditions, greatly reducing the generation of impurities and greatly obtaining phosphonic salt with an increased E content. The yield of lycopene obtained by using the phosphonic salt as a raw material is high.


Patent
Nanjing University of Technology and Zhejiang Medicine Co. | Date: 2012-12-10

Provided in the present invention is a method for synthesizing 2,7-dimethyl-2,4,6-octatriene-1,8-dialdehyde. The synthesis method comprises the following steps: (1) adding acetaldehyde diethyl acetal and ethyl-(1-propenyl)-ether under the effect of a catalyst to produce 1,1,3-triethoxy-2-methyl-butane; (2) pyrolysis synthesizing 1,1,3-triethoxy-2-methyl-butane under the catalytic effects of isoquinoline and p-Toluenesulfonic acid to produce 1-methoxy-2-methyl-1,3-butadiene; (3) dissolving 1-methoxy-2-methyl-1,3-butadiene in anhydrous ethanol solvent for synthesis with a phase transfer catalyst, cetyl-trimethyl ammonium bromide, and a chlorinating agent, trichloroisocyanuric acid, to generate 4,4-diethoxy-3-methyl-1-chloro-butene; (4) combining 4,4-diethoxy-3-methyl-1-chloro-butene with a triphenylphosphine salt to produce a phosphonium salt; and (5) condensing the phosphonium salt under the effects of hydrogen peroxide in conjunction with sodium carbonate solution to generate 1,1,8,8-tetramethyl-2,7-dimethyl-2,4,6-octatriene; then hydrolyzing under acidic conditions to synthesize 2,7-dimethyl-2,4,6-octatriene-1,8-dialdehyde. The present invention has a simple process route, is easy to operate, and has mild conditions, great yield, and great industrial value.


Zhang X.,Nanjing University of Technology | Mao D.,Nanjing University of Technology | Leng Y.,Jiangnan University | Zhou Y.,Nanjing University of Technology | Wang J.,Nanjing University of Technology
Catalysis Letters | Year: 2013

The heteropolyanion-based ionic liquid (IL) material [MIMPS] 3PW12O40, propane sulfoacid-functionalized imidazolium salt of phosphotungstate, was used as a solid catalyst for liquid-phase Beckmann rearrangements of ketoximes in the presence of zinc chloride. The resultant liquid-solid biphasic rearrangement reaction of cyclohexanone oxime shows a high yield 83 % with good recyclability. The testing of control catalysts, reaction conditions, oxime substrates, and recycling property were carried out and the results are discussed. Graphical Abstract: The heteropolyanion-based ionic liquid (IL) material [MIMPS]3PW 12O40, propane sulfoacid-functionalized imidazolium salt of phosphotungstate, was used as a solid catalyst for liquid-phase Beckmann rearrangements of ketoximes in the presence of zinc chloride. The resultant liquid-solid biphasic rearrangement reaction of cyclohexanone oxime shows a high yield 83% with good recyclability. The testing of control catalysts, reaction conditions, oxime substrates, and recycling property were carried out, and the results are discussed.[Figure not available: see fulltext.] © 2012 Springer Science+Business Media New York.


Song J.,CAS Shanghai Advanced Research Institute | Li X.-M.,CAS Shanghai Advanced Research Institute | Figoli A.,University of Calabria | Huang H.,Nanjing University of Technology | And 3 more authors.
Water Research | Year: 2013

A high performance versatile composite hollow fiber nanofiltration (NF) membrane is reported for the separation of glyphosate from saline waste streams. Preparation of SPEEK based on an amorphous poly (ether ether ketone, PEEK) was investigated. The membrane was prepared by coating sulfonated polyether ether ketone (SPEEK) onto a polyethersulfone (PES) ultrafiltration (UF) hollow fiber membrane. The composite membrane was characterized by water permeability, scanning electron microscopy, and rejection toward sodium sulfate (Na2SO4), sodium chloride (NaCl), and calcium chloride (CaCl2). About 90% rejection toward sulfate anions and only 10% rejection for calcium cations were obtained. A water permeability around 10-13 LMHBar and 90% rejection for polyethylene glycol (PEG) with a molecular weight of 4000-6000 Da were observed. In the separation of glyphosate from saline wastewater, the membrane rejected less than 20% of NaCl and higher than 90% of glyphosate at an operating pressure of 5 bars and pH = 11.0. An economic analysis indicated that the cost for recovery of glyphosate was comparably low to the value gained by an increase in the productivity. The results may lead to a new promising low energy solution for the environmental problem faced by the herbicide industry. © 2013 Elsevier Ltd.


Yu W.,Nanjing University of Technology | Qiang J.,Nanjing University of Technology | Yin J.,Central China Normal University | Kambam S.,Nanjing University of Technology | And 3 more authors.
Organic Letters | Year: 2014

Two dinuclear copper complexes with and without ammonium moieties were synthesized. The complexes exhibited selective binding affinity to pyrophosphate in aqueous solution. The dinuclear copper complex, with ammonium arms, showed a ca. 527-fold enhancement in pyrophosphate binding affinity compared with its analogue without ammonium units. © 2014 American Chemical Society.


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.


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.


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.


Ke Q.,Wenzhou University | Jin Y.,Wenzhou University | Jiang P.,Wenzhou University | Yu J.,Nanjing University of Technology
Langmuir | Year: 2014

Superhydrophobic and superoleophilic sponges were fabricated by immersion in an ethanol solution of octadecyltrichlorosilane. The resulting coating strongly adheres to the sponges after curing at 45 °C for 24 h. Absorption capacities of 42-68 times the polymerized octadecylsiloxane sponge weight were obtained for toluene, light petroleum, and methylsilicone oil. These adsorption capacities were maintained after 50 cycles. © 2014 American Chemical Society.


Wang J.,Nanjing University of Technology | Wang J.,Nanjing Beilida New Materials System Engineering Co. | Lu C.,Nanjing University of Technology | Xiong J.,Nanjing Beilida New Materials System Engineering Co.
Applied Surface Science | Year: 2014

Environmental pollution has an evidently adverse impact on the buildings that are constructed by the glass fiber reinforced cement (GRC) materials. In the present work, the stable, neutral TiO2/SiO2 hydrosols were prepared by using the Ti(SO4)2 as titanium source, HNO3 as peptizing agent, and SiO2 as stabilizer through a simple and low cost process. The morphologies and structures of TiO 2/SiO2 hydrosol were further characterized by the TEM, SEM, XRD, and FTIR measurement. In the synthetic hydrosol, lots of nanoparticles with the diameters in the range of 10-20 nm can be observed. TiOSi band were formed, as observed from the FTIR spectrum. The Na2O·SiO 2 was detected from the SEM. After drying the TiO2/ SiO2 hydrosol, the XRD shown that the TiO2 has an anatase structure and the SiO2 is amorphous. The TiO2/SiO 2 hydrosol can be compactly coated on the GRC surface due to the existence of Na2O·SiO2 binder and exhibited high photocatalytic activity and stability in the degradation of Rhodamine B. © 2014 Elsevier B.V.


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.


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 M.,Nanjing University of Technology | Zhao P.,Nanjing University of Technology | Leng Y.,Jiangnan University | Chen G.,Nanjing University of Technology | And 2 more authors.
Chemistry - A European Journal | Year: 2012

An acid-base bifunctional ionic solid catalyst [PySaIm] 3PW was synthesized by the anion exchange of the ionic-liquid (IL) precursor 1-(2-salicylaldimine)pyridinium bromide ([PySaIm]Br) with the Keggin-structured sodium phosphotungstate (Na 3PW). The catalyst was characterized by FTIR, UV/Vis, XRD, SEM, Brunauer-Emmett-Teller (BET) theory, thermogravimetric analysis, 1H NMR spectroscopy, ESI-MS, elemental analysis, and melting points. Together with various counterparts, [PySaIm] 3PW was evaluated in Knoevenagel condensation under solvent and solvent-free conditions. The Schiff base structure attached to the IL cation of [PySaIm] 3PW involves acidic salicyl hydroxyl and basic imine, and provides a controlled nearby position for the acid-base dual sites. The high melting and insoluble properties of [PySaIm] 3PW are relative to the large volume and high valence of PW anions, as well as the intermolecular hydrogen-bonding networks among inorganic anions and IL cations. The ionic solid catalyst [PySaIm] 3PW leads to heterogeneous Knoevenagel condensations. In solvent-free condensation of benzaldehyde with ethyl cyanoacetate, it exhibits a conversion of 95.8 % and a selectivity of 100 %; the conversion is even much higher than that (78.2 %) with ethanol as a solvent. The solid catalyst has a convenient recoverability with only a slight decrease in conversion following subsequent recyclings. Furthermore, the new catalyst is highly applicable to many substrates of aromatic aldehydes with activated methylene compounds. On the basis of the characterization and reaction results, a unique acid-base cooperative mechanism within a Schiff base structure is proposed and discussed, which thoroughly explains not only the highly efficient catalytic performance of [PySaIm] 3PW, but also the lower activities of various control catalysts. Cooperative catalyst: The ionic solid prepared by pairing pyridine-based Schiff base tethered cations with phosphotungstate anions is proved to be a recoverable efficient heterogeneous catalyst for Knoevenagel condensations by means of the unique bulk-type acid-base cooperative mechanism (see scheme). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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.


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.


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.


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.


Zhao P.,Nanjing University of Technology | Leng Y.,Jiangnan University | Zhang M.,Nanjing University of Technology | Wang J.,Nanjing University of Technology | And 2 more authors.
Chemical Communications | Year: 2012

An ionic solid catalyst by pairing Keggin polyoxometalate-anions with Pd II-coordinated nitrile-tethered ionic liquid cations was synthesized, characterized, and tested for aerobic oxidation of benzene to biphenyl. A unique heterogeneous intramolecular electron transfer mechanism is proposed to understand its high activity. This journal is © 2012 The Royal Society of Chemistry.


Wang C.,Xi'an University of Science and Technology | Jiang B.,Nanjing University of Technology | Liu M.,General Motors | Ge Y.,Xi'an 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.


Zhao P.,Nanjing University of Technology | Leng Y.,Jiangnan University | Wang J.,Nanjing University of Technology
Chemical Engineering Journal | Year: 2012

A heteropolyanion-based cross-linked ionic copolymer was prepared by the anion-exchange of heteropolyacid (HPA) H 5PMo 10V 2O 40 with polymeric ionic liquid (PIL) poly(divinylbenzene-3-n-butyl-1-vinylimidazolium)Br, and characterized by FI-IR, UV-vis, XRD, TG, SEM, elemental analysis and BET surface areas. The characterization results show that the ionic copolymer is an amorphous HPA salt of PIL-cation with a considerable thermal stability, high surface area and large pore volume. Further, the ionic copolymer is revealed to be a highly efficient heterogeneous catalyst for hydroxylation of benzene with H 2O 2 to phenol, showing high activity, convenient recovery and steady reuse. The excellent performance of the novel porous HPA-based copolymer catalyst is discussed in relation to its textural property and intramolecular charge transfer behavior. © 2012 Elsevier B.V.


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

A new SO 3H-functionalized HPA-based acidic polymeric hybrid was prepared by coupling task-specifically designed SO 3H-functionalized polymeric ionic liquid with Keggin-structured heteropolyanion, and characterized by 1H NMR, FT-IR, TG, XRD, BET, Hammett indicator, melting point, and elemental analysis. Its catalytic performance for esterification of alcohols with carboxylic acids was studied under solvent-free conditions. The results demonstrate that the polymeric hybrid is a highly active and selective solid catalyst for various esterifications, and can be easily recovered and steadily reused. © 2011 Elsevier B.V. All rights reserved.


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.


Cardoso J.C.,Nanjing University of Technology | Grimes C.A.,Nanjing University of Technology | Feng X.,Flux Photon Corporation | Zhang X.,Nanjing University of Technology | And 3 more authors.
Chemical Communications | Year: 2012

We report on low-cost, all solution fabrication of efficient air-stable nanostructured thin film photovoltaics comprised of n-type Sb 2S 3 chemically deposited onto TiO 2 nanowire array films, forming coaxial Sb 2S 3/TiO 2 nanowire hybrids vertically oriented from the SnO 2:F coated glass substrate, which are then intercalated with poly(3-hexylthiophene) (P3HT) for hole transport and enhanced light absorption. This journal is © The Royal Society of Chemistry 2012.


Lee K.M.,Ewha Womans University | Chen X.,Nanjing University of Technology | Fang W.,Ewha Womans University | Kim J.-M.,Hanyang University | Yoon J.,Ewha Womans University
Macromolecular Rapid Communications | Year: 2011

A PDA based sensor, derived from a di-(2-picolyl) amine (DPA) substituted diacetylene monomer, displayed a selective colorimetric change and a large fluorescence enhancement in the presence of lead ions. The lead selective PDA-based chemosensor enabled easy detection of the presence of lead in 100% aqueous solution by the naked-eye. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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.


Wang F.,Ewha Womans University | Wang F.,Nanjing University of Technology | Wang L.,Nanjing University of Technology | Chen X.,Nanjing University of Technology | Yoon J.,Ewha Womans University
Chemical Society Reviews | Year: 2014

The presence of cyanide ions in surface water is not only caused by industrial waste but also by biological processes. Owing to the extreme toxicity of cyanide in physiological systems and its widespread presence in the environment, considerable attention has been given to the development of methods for the detection of cyanide. Among the most simple, inexpensive and rapid methods to detect cyanide ions are chemosensors that rely on fluorometric and colorimetric responses. This review, which focuses on CN- fluorescence and colorimetric chemosensors that have been developed since 2010, follows a format in which the sensors are classified according to their structural features and reaction mechanisms. Finally, a general overview of the design of fluorometric and colorimetric chemosensors for CN- is provided. © 2014 The Royal Society of Chemistry.


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.


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.


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.


Shen J.,Nanjing University of Technology | Liu G.,Nanjing University of Technology | Huang K.,Nanjing University of Technology | Jin W.,Nanjing University of Technology | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2015

Graphene oxide (GO) nanosheets were engineered to be assembled into laminar structures having fast and selective transport channels for gas separation. With molecular-sieving interlayer spaces and straight diffusion pathways, the GO laminates endowed as-prepared membranes with excellent preferential CO2 permeation performance (CO2 permeability: 100 Barrer, CO2/N2 selectivity: 91) and extraordinary operational stability (> 6000 min), which are attractive for implementation of practical CO2 capture. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA.


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.


Jin X.,Zhejiang University of Technology | Zhou B.,Nanjing University of Technology | Xue L.,Nanjing University of Technology | San W.,Zhejiang University of Technology
Biomedicine and Pharmacotherapy | Year: 2015

Inhibiting or circumventing drug resistance by using drug delivery systems (DDSs) such as micelles has attracted significant attention recently. In this present study, a polyvinyl caprolactam-polyvinyl acetate-polyethylene (Soluplus®) micelle was developed as the delivery system for doxorubicin (DOX) and evaluated both in vitro and in vivo. In vitro, Soluplus® micelles could significantly enhance the cellular accumulation of DOX in MCF-7/DOX cells, meanwhile, P-glycoprotein (P-gp)-mediated drug efflux was inhibited which was also verified in the membrane fluidity study. And MCF-7/DOX cells were found to be more susceptible to the cytotoxic effects of DOX-M. In vivo, both the P-gp inhibitors verapamil and Soluplus® could improve the cytotoxicity of DOX·HCl in MCF-7/DOX tumor-bearing mice, which were further certified by the effect of Soluplus® on P-gp inhibition. Furthermore, the excellent antitumor efficacy of DOX-M by intravenous injection was also observed, which indicated that the P-gp inhibition effect of Soluplus® could enhance the susceptibility of resistant tumor to DOX in vivo. In conclusion, our study suggested that Soluplus® micelles might be an applicable drug delivery system for enhancing the antitumor efficacy of P-gp substrates. © 2014 Elsevier Masson SAS.


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.


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.


Chen X.,Ewha Womans University | Chen X.,Nanjing University of Technology | Pradhan T.,Korea University | Wang F.,Ewha Womans University | And 2 more authors.
Chemical Reviews | Year: 2012

Different xanthene derivatives according to their analytes with mechanistic schemes published from 1997 to February 2011 are introduced. Kim and co-workers reported the design and synthesis of a new rhodamine-based derivative, bearing an N-butyl-1,8-naphthalimide group. Huang's and Li's groups reported a rhodamine B derivative, containing a highly electron-rich S atom as a fluorescence turn-on chemodosimeter for Cu 2+ in an aqueous medium. Peng et al. reported a rhodamine-based chemodosimeter, via a mechanism of Hg 2+-promoted hydrolysis. Lin et al. presented a rhodamine-based probe, composed of a sulfur atom and an alkyne moiety for the irreversible detection of Hg 2+. Shang et al. synthesized molecule, composed of a fluorescein fluorophore and a rhodamine B hydrazide linked together by a thiourea spacer. Nagano and co-workers have synthesized a series of symmetric and asymmetric rhodamine derivatives,using rhodamine as scaffolds.


Chen X.,Ewha Womans University | Chen X.,Nanjing University of Technology | Zhou G.,Nanjing University of Technology | Peng X.,Dalian University of Technology | Yoon J.,Ewha Womans University
Chemical Society Reviews | Year: 2012

Polydiacetylenes (PDAs), a family of conjugated polymers, have very unique electrical and optical properties. Upon environmental stimulation, such as by viruses, proteins, DNAs, metal ions, organic molecules etc., the blue PDAs can undergo a colorimetric transition from blue to red, which is accompanied by a fluorescence enhancement. Since the first report on polymerized diacetylene molecules as sensors of influenza virus, the development of efficient sensory systems based on PDAs continues to be of great interest. This tutorial review highlights the recent advances in bio- and chemo-sensors derived from polydiacetylenes. © 2012 The Royal Society of Chemistry.


Tong L.,Nanjing University of Technology | Cheng B.,Tianjin Polytechnic University | Liu Z.,1815iversity Street | Wang Y.,Nanjing University of Technology
Sensors and Actuators, B: Chemical | Year: 2011

Polydiacetylene (PDA), as a unique conjugated polymer, has shown its potential in the application of chem/bio-sensors and optoelectronics. In this work, we first infiltrated PDA monomer (10, 12-pentacosadiynoic acid, PCDA) melt into anodized aluminum oxide template, and then illuminated the infiltrated template with UV light to initiate the polymerization of PCDA. After etching away the aluminum oxide templates, we obtained solid poly-PCDA nanofibers. We found that even tightly confined in template pores with diameter as small as ∼35 nm, PCDA crystals were able to be polymerized through a solid polymerization mechanism induced by UV light. Poly-PCDA nanofibers, both in the released form and embedded in the template, showed characteristic blue to red color change in sensing exposure of organic solvents and temperature increasing, and the red colored fibers possessed strong fluorescence. Moreover, poly-PCDA nanofibers were highly crystalline, and oriented favorably in some certain direction due to the confinement of nanopores, as demonstrated by X-ray diffraction texture analysis and orientation distribution analysis by scanning confocal optical microscopy. © 2011 Elsevier B.V. All rights reserved.


Su J.,Xi'an Jiaotong University | Guo L.,Xi'an Jiaotong University | Bao N.,Nanjing University of Technology | Grimes C.A.,Nanjing University of Technology
Nano Letters | Year: 2011

We report on a novel heterojunction WO3/BiVO4 photoanode for photoelectrochemical water splitting. The heterojunction films are prepared by solvothermal deposition of a WO3 nanorod-array film onto fluorine-doped tin oxide (FTO) coated glass, with subsequent deposition of a low bandgap, 2.4 eV, visible light responding BiVO4 layer by spin-coating. The heterojunction structure offers enhanced photoconversion efficiency and increased photocorrosion stability. Compared to planar WO 3/BiVO4 heterojunction films, the nanorod-array films show significantly improved photoelectrochemical properties due, we believe, to the high surface area and improved separation of the photogenerated charge at the WO3/BiVO4 interface. Synthesis details are discussed, with film morphologies and structures characterized by field emission scanning electron microscopy and X-ray diffraction. © 2011 American Chemical Society.


Chen D.,Nanjing University of Technology | Huang C.,Nanjing University of Technology | Ran R.,Nanjing University of Technology | Park H.J.,Samsung | And 2 more authors.
Electrochemistry Communications | Year: 2011

Ba0.5Sr0.5Co0.8Fe0.2O 3-δ (BSCF) + Co3O4 composites with different Co3O4 contents were synthesized, and their properties and performance as cathodes in IT-SOFCs were investigated. The diffraction patterns of the composites were well indexed based on the physical mixture of the BSCF phase and the Co3O4 phase. A surprising increase in the total conductivity of the composites was observed even though Co3O4 is a p-type semiconductor with a low conductivity. Electrochemical impedance spectra of symmetric cells indicated that both the area specific resistance and the activation energy were reduced in samples with Co3O4 contents of 5-20 wt.% with minimum values reaching 10 wt.%. A synergistic effect likely occurred between BSCF and Co3O4 that led to the better performance. An anode-supported single cell with 90 wt.% BSCF + 10 wt.% Co3O 4 delivered a promising peak power density of 1150 mW cm - 2 at 600 °C. © 2011 Elsevier B.V.


Shao Z.,Nanjing University of Technology | Zhang C.,Nanjing University of Technology | Wang W.,Nanjing University of Technology | Su C.,Nanjing University of Technology | And 4 more authors.
Angewandte Chemie - International Edition | Year: 2011

A harmonic generator: Co-generation of electric power and synthesis gas from methane is achieved using a single-chamber solid oxide fuel cell (see picture; SDC=samarium-doped ceria, YSZ=yttrium-stabilized zirconia). The process utilizes methane completely with zero greenhouse gas emissions. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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.


Dong F.,Nanjing University of Technology | Chen D.,Nanjing University of Technology | Ran R.,Nanjing University of Technology | Park H.,Samsung | And 2 more authors.
International Journal of Hydrogen Energy | Year: 2012

Sm0.5Sr0.5MO3-δ (M = Co and Mn) materials are synthesized, and their properties and performance as cathodes for solid oxide fuel cells (SOFCs) on Sm0.2Ce0.8O 1.9 (SDC) and Y0.16Zr0.92O2.08 (YSZ) electrolytes are comparatively studied. The phase structure, thermal expansion behavior, oxygen mobility, oxygen vacancy concentration and electrical conductivity of the oxides are systematically investigated. Sm 0.5Sr0.5CoO3-δ (SSC) has a much larger oxygen vacancy concentration, electrical conductivity and TEC than Sm 0.5Sr0.5MnO3-δ (SSM). A powder reaction demonstrates that SSM is more chemically compatible with the YSZ electrolyte than SSC, while both are compatible with the SDC electrolyte. EIS results indicate that the performances of SSC and SSM electrodes depend on the electrolyte that they are deposited on. SSC is suitable for the SDC electrolyte, while SSM is preferred for the YSZ electrolyte. A peak power density as high as 690 mW cm-2 at 600°C is observed for a thin-film SDC electrolyte with SSC cathode, while a similar cell with YSZ electrolyte performs poorly. However, SSM performs well on YSZ electrolyte at an operation temperature of higher than 700°C, and a fuel cell with SSM cathode and a thin-film YSZ electrolyte delivers a peak power density of ∼590 mW cm-2 at 800°C. The poor performances of SSM cathode on both YSZ and SDC electrolytes are obtained at a temperature of lower than 650°C. Copyright © 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.


Xiao J.,Nanjing University of Technology | Hsein Juang C.,Clemson University | Wei K.,Southwest Jiaotong University | Xu S.,Nanjing University of Technology
Journal of Geotechnical and Geoenvironmental Engineering | Year: 2014

The authors investigated the effects of principal stress rotation (PSR) on the traffic load-induced settlement of subways in soft subsoil. Here, a series of hollow cylinder tests on normally consolidated, medium-plasticity soft clay with and without principal stress rotation were performed along with finite-element modeling and simulation. The results show significant increases in both excess pore-water pressure and cumulative deformation of the normally consolidated soft clay when PSR is present and simulated, and the effects become more pronounced as the maximum effective principal stress ratio or load frequency increases. Under the actual traffic load-induced stress in subsoil below the subway tunnel, the presence of PSR increases the cumulative deformation of soft clay by 9-23% compared with that without PSR. As an approximation, the cumulative deformation of soft clay with the effect of PSR can be estimated by multiplying the deformation derived from the repeated triaxial testing without PSR with the ratio of axial strain between the two tests. © 2013 American Society of Civil Engineers.


Chen Y.,Nanjing University of Technology | Wang F.,Nanjing University of Technology | Chen D.,Nanjing University of Technology | Dong F.,Nanjing University of Technology | And 3 more authors.
Journal of Power Sources | Year: 2012

The long-term stability for oxygen reduction reaction (ORR) of two typical perovskite cathode materials of SOFCs, i.e., Ba 0.5Sr 0.5Co 0.8Fe 0.2O 3-δ (BSCF) and Sm 0.5Sr 0.5CoO 3-δ (SSC), is investigated in a symmetric cell configuration under air condition at 700 °C using Sm 0.2Ce 0.8O 1.9 (SDC) electrolyte substrate and silver current collectors. Moreover, two different methods of silver current collection are tested, i.e., whole electrode surface deposited with a diluted silver paste (CC-01) and a mesh-like current collector using concentrated silver paste (CC-02). Electrochemical impedance spectra are applied for stability investigations. With the CC-01 current collector, the performance of the electrode deteriorates significantly, although the initial performance is good. By contrast, fairly stable performance is obtained from symmetric cells with either BSCF or SSC + SDC electrodes using the CC-02 current collector, even though a phase transition is observed for BSCF. For instance, after approximately 800 h of continuous stability testing, the area-specific resistance of the BSCF electrode retains a value of approximately 0.065 Ω cm 2, except for a slight fluctuation within the range of 0.06-0.07 Ω cm 2. These findings reveal that both BSCF and SSC can be stably operated for ORR under symmetric cell conditions; however, an appropriate current collection method is crucial to achieving stable performance. © 2012 Elsevier B.V. All rights reserved.


Lin Y.,Nanjing University of Technology | Su C.,Nanjing University of Technology | Huang C.,Nanjing University of Technology | Kim J.S.,Samsung | And 2 more authors.
Journal of Power Sources | Year: 2012

A new symmetric SOFC with an SDC framework and a silver-infiltrated electrocatalyst is presented for the first time in this paper. A three-electrode polarization test shows that the Ag-SDC has a low area specific resistance of 1.07 Ω cm2 at 600 °C, a low activation energy of 85 kJ mol-1 and high exchange current densities of 428.2 and 129.0 mA cm-2 at 750 and 650 °C, respectively, when it is used as an oxygen reduction electrode. It also exhibits low polarization resistance in a humidified hydrogen atmosphere. A symmetric single cell is used in real fuel cell conditions to deliver peak power densities of 200 and 84 mW cm-2 at 750 and 650 °C, respectively, when humidified hydrogen is used as a fuel and ambient air is used as the cathode atmosphere. The cell still reaches a peak power density of 81 mW cm-2 at 750 °C when operating on CO. O2-TPO analysis demonstrates that the Ag-SDC electrode has even better coking resistance than the pure SDC scaffold. The results indicate that Ag-SDCSDCAg-SDC symmetric cells with an infiltrated silver electrocatalyst are a promising new type of fuel cell for use with both hydrogen fuel and carbon-containing fuels. © 2011 Elsevier B.V. All rights reserved.


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.


Huang H.,University of Nevada, Las Vegas | Huang H.,Nanjing University of Technology | Kang J.Y.,University of Nevada, Las Vegas
Organic Letters | Year: 2016

An efficient amine-catalyzed phospha-Michael addition reaction of α,β-unsaturated aldehydes/ketones with N-heterocyclic phosphines for the synthesis of Î-ketodiazaphosphonates has been developed. With freedom from nucleophile additives, this mild process affords a range of structurally diverse Î-ketodiazaphosphonates in moderate to excellent yields. Importantly, various α,β-unsaturated ketones were also tolerated in this process and gave moderate yields. © 2016 American Chemical Society.


Fang Z.,Nanjing University of Technology | Yang H.,Nanjing University of Technology | Qiu Y.,Xi'an Jiaotong University
IEEE Transactions on Plasma Science | Year: 2010

Drived by a μs pulse high-voltage power supply, a homogeneous DBD in atmospheric air is generated between two plane-parallel electrodes, with PTFE plates as dielectric barriers. The discharge generated shows homogeneous discharge characteristics. The light emission is radially homogeneous and covers the entire surface of the electrodes, and a single current pulse with duration of about 1 μs and amplitude of less than 1 A appears in each voltage pulse. The homogeneous DBD is used to treat the polyethylene terephthalate (PET) films to improve their surface hydrophilicity, and as the main operating parameters, the effects of discharge power density of the homogeneous DBD on the surface treatment are also studied. The surface properties of PET films before and after treatments are studied using the following: 1) contact angle and surface energy measurement; 2) attenuated total reflection fourier transform infrared spectroscopy (ATR-FTIR); 3) x-ray photoelectron spectroscopy (XPS); and 4) scanning electron microscopy (SEM). The results of contact angle and surface energy measurements reveal that the homogeneous DBD treatment can improve the surface hydrophilicity of PET films, as it can induce a remarkable decrease in water contact and a remarkable increase in surface energy. The results of SEM, XPS, and FTIR shows that improvement of the hydrophilicity due to both the introduction of oxygen-containing polar groups onto the surface and the etching of the surface. It is found that increasing discharge power density of homogeneous DBD can induce more effective treatment of PET films, and less treatment time is needed to achieve the same level of surface treatment by increasing the discharge power density. © 2006 IEEE.


Liu J.,Nanjing Normal University | Wang F.,Nanjing University of Technology | Qi S.,Nanjing Normal University | Gu Z.,Nanjing Normal University | Wu G.,Nanjing Institute of Technology
New Journal of Chemistry | Year: 2013

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. To investigate the origin of the GNPs, the solids were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and other instruments. Some reaction parameters, such as solvent, oxidant concentration, catalyst concentration and reaction time, have been investigated and reaction conditions are optimized. This journal is © 2013 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.


Xu W.,Nanjing University of Technology | Yang J.,Nanjing University of Technology | Jin Y.,Nanjing Institute of Technology | Qiu T.,Nanjing University of Technology
Journal of the European Ceramic Society | Year: 2013

N,N-Dimethylacrylamide (DMAA)/N,N'-methylenebis (acrylamide) (MBAM) system was used in the aqueous YIG (yttrium iron garnet) slurry. YIG powders were prepared by using Y2O3 and Fe2O3 as raw materials through the traditional oxide method. In order to reduce the viscosity and improve the stability of slurries, SD-03 (ammonium polyacrylate) was selected as the dispersant. Zeta potential, pH, dispersant dosage, solid loading and milling time have been optimized. The best conditions were pH 9.86, dispersant dosage 0.2wt.% and milling time 9h, which helped to prepare the concentrated slurry with low viscosity and good liquidity. The maximum bending strength of the green body could be up to 13MPa. The shrinkage and deformation of shaped sintered bodies prepared through gelcasting were small after sintering. The sintering shrinkage, apparent porosity and bulk density were 17%, 0.17% and 5.07g/cm3, respectively. The dielectric constant and dielectric loss were 14.0 and 2.06×10-4, respectively. © 2012 Elsevier Ltd.


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.


Zha C.,Nanjing University of Technology | Shen L.,Nanjing University of Technology | Zhang X.,Nanjing University of Technology | Wang Y.,Nanjing University of Technology | And 3 more authors.
ACS Applied Materials and Interfaces | Year: 2014

We describe a seeded hydrothermal process for the growth of unique double-sided brush-shaped (DSBS) TiO2 nanostructure assemblies consisting of highly ordered rutile nanowires vertically aligned around an annealed TiO2 nanoparticle layer. The annealed TiO2 nanoparticle layer seeds the nanowire growth and also supports the DSBS structure. The morphology of the DSBS TiO2 nanostructure depends on the hydrothermal reaction time. The diameter of the nanowires is about 6.6 nm, and with increasing reaction time from 1 to 8 h the nanowire length increases from 0.6 to 6.2 μm, whereas the thickness of the nanoparticle layer decreases from 4.3 to 2.8 μm. These free-standing nanowire arrays provide large internal surface area, which is essential for minimizing carrier recombination in high performance photovoltaic devices. Furthermore, the nanowire architecture can help increase the rate of charge transport as compared to particulate films because of lower concentration of grain boundaries. The power conversion efficiency of backside (DSBS TiO2/FTO photoanode) illuminated dye-sensitized solar cells fabricated using the DSBS TiO2 nanostructure assembly is found to be depended on the nanowire length. A cell fabricated using 15.2 μm thick nanostructures sensitized by N719 has a short-circuit current density of 12.18 mA cm-2, 0.78 V open circuit potential, and a 0.59 filling factor, yielding a maximum power conversion efficiency of 5.61% under AM 1.5 illumination. © 2013 American Chemical Society.


Chen X.,Nanjing University of Technology | Tian R.,Nanjing University of Technology | Zhang Q.,Nanjing Sichuang Biotechnology Co. | Yao C.,Nanjing University of Technology
Biosensors and Bioelectronics | Year: 2014

A novel strategy for selective and sensitive amperometric detections of Pb2+ was proposed based on the three dimensional ordered macroporous (3DOM) Au-Pd bimetallic electrode and target-induced methylene blue-single walled carbon nanotubes (MB-SWCNTs) as signal reporter. A DNA biosensor was fabricated by immobilizing capture probe DNA on the 3DOM Au-Pd bimetallic electrode, which further hybridized with the reporter DNA loaded on the MB-SWCNTs adduct upon the exposure of Pb2+, inducing measurable electrochemical signal. Due to the dramatic signal amplification by the enhanced immobilization of DNA on the surface of 3DOM Au-Pd bimetallic electrode and MB-SWCNTs, coupling the low background signal produced by blank solution, ultra-low level (1×10-19M) of Pb2+ could be detected. Under the optimal conditions, the electrochemical signal of the MB increased with the increasing Pb2+ concentration, exhibiting a linear response in the range of 1×10-17-1×10-4M. Furthermore, with the application of Pb2+ dependent DNAzyme, the proposed sensing system demonstrated high selectivity. This work represented a promising potential for on-site testing Pb2+ in real drinking water and serum sample analysis. © 2013 Elsevier B.V.


Wang J.D.,Nanjing University of Technology | Lo S.H.,University of Hong Kong | Zhou D.,Nanjing University of Technology
Journal of Fluids and Structures | Year: 2012

A semi-analytical approach is presented to obtain the natural frequencies and vibration modes of ideal liquid sloshing in a rigid partially liquid-filled cylindrical container with multiple rigid annular baffles of the same inner radius. The complicated liquid domain is divided into several simple sub-domains so that the liquid velocity potential in each liquid sub-domain is of class C 1 with continuity boundary conditions. Based on the superposition principle, the analytical solutions of the liquid velocity potential corresponding to each liquid sub-domain are obtained by means of the method of separation of variables. The eigenfrequency equation is obtained by expanding the free surface condition and the artificial interface conditions into the Fourier series in the liquid height direction and the Bessel series in the radial direction. Stable and fast numerical computations are observed by the convergence study. Excellent agreements have been achieved in the comparison of results obtained by the proposed approach with those given by finite element software ADINA. The natural frequencies and mode shapes versus the position, the inner radius and the number of the annular baffles are discussed in detail. © 2012 Elsevier Ltd.


Zhang Q.,Nanjing University of Technology | Chen X.,Nanjing University of Technology | Tu F.,Nanjing Sichuang Biotechnology Co. | Yao C.,Nanjing University of Technology
Biosensors and Bioelectronics | Year: 2014

The measurement of free thyroxine concentration in serum is considered to be an essential indicator of thyroid function. Here, a novel enzyme-free sandwich electrochemical immunosensor for the detection of FT4 antigen based on the immobilization of primary antibody (Ab1) on three dimensional ordered macroporous chitosan-Au nanoparticles hybrid (3DOM CS-AuNPs) film electrode, and magnetic multiwall carbon nanotubes (MMWCNTs) were used as label of secondary antibody (Ab2). The 3DOM CS-AuNPs film electrode was constructed by one-step electrodeposition of CS-AuNPs composite onto Au electrode with silica opal template. MMWCNTs were prepared by chemical co-precipitation of Fe2+ and Fe3+ salts on carboxylated MWCNTs. Ru(bpy)32+ labeled anti-FT4 (Ru(bpy)32+-Ab2) was covalently attached to MMWCNTs through the formation of amide bond between the carboxylic groups of MWCNTs and the amine groups of antibody. Under the optimal conditions, FT4 was detected in a concentration range from 0.71fgmL-1 to 1.15pgmL-1 with a correlation coefficient of 0.998 and a detection limit of 0.20fgmL-1. Moreover, the immunosensor showed excellent selectivity, good stability, satisfactory reproducibility and regeneration. Importantly, the developed method was used to assay clinical serum specimens, achieving a good relation with those obtained from the commercialized electrochemiluminescent method. © 2014 Elsevier B.V.


Wang B.,Nanjing University of Technology | Wang B.,University of Cambridge | Wu X.,Nanjing University of Technology | Zhao H.,Beijing Institute of Technology
Mathematical and Computer Modelling | Year: 2013

This paper presents two novel improved multidimensional Störmer-Verlet formulas with four applications to time-independent Schrödinger equations, wave equations, orbital problems and the problem of Fermi, Pasta & Ulam. For solving the system of second-order ordinary differential equations y″+My=f(t, y) with M∈Rm×m, the multidimensional ARKN methods (adapted Runge-Kutta-Nyström methods) were formulated by Wu etal. (2009)[1]. Very recently, the multidimensional ERKN methods (extended Runge-Kutta-Nyström methods) were proposed by Wu etal. (2010)[26]. Both the ARKN methods and the ERKN methods perform numerically much better than the classical Runge-Kutta-Nyström methods due to the use of the special structure of the equation brought by the linear term My. Based on the two kinds of multidimensional schemes, we derive two novel improved multidimensional Störmer-Verlet formulas, which are shown to be symplectic and of order two. Each new formula is a blend of existing trigonometric integrators and symplectic integrators. Meantime, the symplecticity conditions for the one-stage explicit multidimensional ARKN methods are presented. Stability and phase properties of the two improved formulas are analyzed. Numerical experiments demonstrate that the two improved multidimensional Störmer-Verlet formulas are more efficient than the classical Störmer-Verlet formula and the two other improved Störmer-Verlet methods appeared in the literature. In particular, when applied to a Hamiltonian system, the two symplectic improved multidimensional Störmer-Verlet formulas preserve well the Hamiltonian in the sense of numerical approximation, and have better accuracy than the classical Störmer-Verlet formula and the two other improved Störmer-Verlet methods with the same computational cost. © 2012 Elsevier Ltd.


Gao H.,Xi'an University of Technology | Chang Q.,Xi'an 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.


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.


Zhou D.,Nanjing University of Technology | Lo S.H.,University of Hong Kong
Archive of Applied Mechanics | Year: 2012

The free vibration of annular thick plates with linearly varying thickness along the radial direction is studied, based on the linear, small strain, three-dimensional (3-D) elasticity theory. Various boundary conditions, symmetrically and asymmetrically linear variations of upper and lower surfaces are considered in the analysis. The well-known Ritz method is used to derive the eigen-value equation. The trigonometric functions in the circumferential direction, the Chebyshev polynomials in the thickness direction, and the Chebyshev polynomials multiplied by the boundary functions in the radial direction are chosen as the trial functions. The present analysis includes full vibration modes, e.g.; flexural, thickness-shear, extensive, and torsional. The first eight frequency parameters accurate to at least four significant figures for five vibration categories are obtained. Comparisons of present results for plates having symmetrically linearly varying thickness are made with others based on 2-D classical thin plate theory, 2-D moderate thickness plate theory, and 3-D elasticity theory. The first 35 natural frequencies for plates with asymmetrically linearly varying thickness are compared to the finite element solutions; excellent agreement has been achieved. The asymmetry effect of upper and lower surface variations on the frequency parameters of annular plates is discussed in detail. The first four modes of axisymmetric vibration for completely free circular plates with symmetrically and asymmetrically linearly varying thickness are plotted. The present results for 3-D vibration of annular plates with linearly varying thickness can be taken as benchmark data for validating results from various plate theories and numerical methods. © 2011 Springer-Verlag.


Wang J.,Nanjing University of Technology | Lo S.H.,University of Hong Kong | Zhou D.,Nanjing University of Technology
Soil Dynamics and Earthquake Engineering | Year: 2014

A new model named double-shear model based on Pasternak foundation and Timoshenko beam theory is developed to evaluate the effect of a forced harmonic vibration pile to its adjacent pile in multilayered soil medium. The double-shear model takes into account the shear deformation and the rotational inertia of piles as well as the shear deformation of soil. The piles are simulated as Timoshenko beams, which are embedded in a layered Pasternak foundation. The differential equation of transverse vibration for a pile is solved by the initial parameter method. The dynamic interaction factors for the layered soil medium are obtained by the transfer matrix method. The formulation and the implementation have been verified by means of several examples. The individual shear effects of soil and piles on the interaction factors are evaluated through a parametric study. Compared to Winkler model with Euler beam, the present model gives much better results for the dynamic interaction of piles embedded in stiff soil with small slenderness ratios. Finally, the effect of a forced long pile to a short pile embedded in multilayered soil medium is studied in detail. © 2014 Elsevier Ltd.


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.


Liu S.-S.,Nanjing University of Technology | Wang C.-F.,Nanjing University of Technology | Wang C.-F.,Jiangsu Key Laboratory of Fine Chemicals and Functional Polymer Materials | Li C.-X.,Nanjing University of Technology | And 4 more authors.
Journal of Materials Chemistry C | Year: 2014

We report a simple and green route to the fabrication of fluorescent carbon dots (CDs), and demonstrate their versatile applications. Hair, a kind of natural and nontoxic raw material, was chosen as the precursor to prepare CDs via a one-step pyrolysis process. The structure and fluorescence properties of the CDs were thoroughly investigated. The obtained CDs can emit bright blue light under UV light with the quantum yield of ca. 17%, and exhibit excitation-, pH- and solvent-dependent fluorescence. The functional groups on the surface of CDs confer these nanomaterials with excellent dispersibility in water and most polar organic solvents, as well as good compatibility with polymer matrices such as poly(methyl methacrylate) and polyvinylpyrrolidone. Then multidimensional CD-polymer hybrid materials, including one-dimensional (1D) microfibers, 2D patterned films and 3D microbeads were constructed with excellent overall performance, which are useful in fluorescent patterns, flat panel displays and anti-counterfeiting labeling fields. This journal is © the Partner Organisations 2014.


Yang T.,Nanjing University of Technology | Yang T.,Jiujiang University | Ma Z.-F.,Nanjing University of Technology | Yang Q.-Y.,Jiujiang University
Desalination | Year: 2011

To develop an efficient dynamic membrane for application in oily wastewater treatment, there is a need to explore an appropriate coating technique and to advance its separation performance. The formation and separation performance of the dynamic membrane from Kaolin and MnO2 were investigated with particular objectives on the choice of an appropriate membrane-coating technique and the discussion of the effect of solution conditions. The microstructures of the dynamic membrane were examined using the scanning electron microscope. The results showed that the deposition of MnO2 particles onto the surface of Kaolin dynamic layer forming a Kaolin/MnO2 bi-layer composite dynamic membrane is an effective coating technique. The optimum concentrations of the Kaolin solution and KMnO4 solution should be 0.4gL-1 and 0.1gL-1 respectively. With the rise of oil concentration, the steady permeate flux decreased and oil retention ratio increased. In the low oil concentration range from 0.1gL-1 to 1.0gL-1, the variation characteristics were more obvious. In neutral or alkaline environments, the dynamic membrane was stable with high permeate flux and oil retention ratio of over 99%. As the temperature rose from 283K to 313K, the steady retention ratio decreased from 99.9% to 98.2% and the steady permeate fluxes increased from 120.1Lm-2h-1 to 153.2Lm-2h-1. © 2010 Elsevier B.V.


Sheng P.,Hunan University | Li W.,Hunan University | Cai J.,Hunan University | Wang X.,Hunan University | And 3 more authors.
Journal of Materials Chemistry A | Year: 2013

Type-II core/shell CdTe/CdS quantum dots (QDs) are assembled onto TiO 2 nanotube array (NTA) films using a bi-functional linker molecule with the help of a hydrothermal method coupled with successive ionic layer adsorption and reaction process. Spatial separation of the electron and hole wave functions within the core/shell heterostructured nanocrystals appears to result in an extended charge separation state, resulting in a significant increase in photocurrent and excellent device stability. When only CdS or CdTe QDs are used as the sensitizer, the largest photocurrent densities are 1.31 mA cm-2 and 1.23 mA cm-2, respectively. For the core/shell CdTe/CdS QDs sensitized TiO2 NTA photoelectrodes the photocurrent density increases to ≈9.17 mA cm-2, dramatically larger than the values obtained with only one sensitizer. The core/shell CdTe/CdS QDs sensitized TiO2 NTA photoelectrodes provide a remarkable photoelectrochemical cell efficiency of 6.12%. To the best of our knowledge this photoconversion efficiency is the highest in the field of QD-sensitized photoelectrodes. A corresponding hydrogen evolution rate as high as 1560 μmol h-1 W-1 was achieved. © 2013 The Royal Society of Chemistry.


Xu Q.,Nanjing University of Technology | Xu Q.,Tianjin University | Li S.,Nanjing University of Technology | Huang H.,Nanjing University of Technology | And 2 more authors.
Biotechnology Advances | Year: 2012

The growing concern about the safety of food and dairy additives and the increasing costs of petroleum-based chemicals have rekindled the interest in the fermentation processes for fumaric acid production. The key problems of the industrial production of microbial fumaric acid are reviewed in this paper. Various strategies, including strain improvement, morphology control, substrate choice, fermentation process and separation process, are summarized and compared, and their economical possibilities for industrial processes are discussed. The market prospects and technological strategies for value-added fumaric acid derivatives are also addressed. The future prospects of microbial fumaric acid production are proposed at the end of this article. © 2012 Elsevier Inc.


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.


Wang H.,Nanjing University of Technology | Zhou G.,Nanjing University of Technology | Gai H.,Hunan University | Chen X.,Nanjing University of Technology
Chemical Communications | Year: 2012

A fluorescent probe based on fluorescein displays excellent selectivity and sensitivity for cysteine and its application for bio-imaging is described. © 2012 The Royal Society of Chemistry.


Jia R.,Nanjing University of Technology | Hu Y.,Nanjing University of Technology | Liu L.,Beijing University of Chemical Technology | Jiang L.,Nanjing University of Technology | And 2 more authors.
ACS Catalysis | Year: 2013

Various functional ionic liquids (ILs) composed of different cations and anions were activated with carbonyldiimidazole and then covalently linked onto porcine pancreatic lipase (PPL) through lysine coupling. Catalytic performances, such as activity, thermostability, and enantioselectivity were improved successfully, as was investigated in p-nitrophenyl palmitate (pNPP) hydrolysis and racemic 1-phenethyl acetate hydrolysis reaction. The correlation between catalytic performance and modification of IL was studied by catalytic and spectroscopic data, which showed improvement of catalytic performances to a different extent. Hydrolytic activity was enhanced by ILs with chaotropic cations and kosmotropic anions (e.g., more than 4-fold with [choline][H 2PO4]). Modifications by ILs bearing kosmotropic cations and chaotropic anions contribute to lipase thermostability and enantioselectivity (e.g., modification with [HOOCBMIm][Cl] showed a 12-fold thermostability increase at 60 C and more than 7-fold enantioselectivity enhancement than native enzyme). The Matrix-assisted laser desorption/ ionization-time-of-flight mass spectrometry experiments suggest that ILs bind with lipase protein. Conformation changes were confirmed by fluorescence spectroscopy, and circular dichroism spectroscopy. © 2013 American Chemical Society.


Zhu X.,Nanjing University of Technology | Liu R.,Nanjing University of Technology | Li Y.,Fudan University | Huang H.,Nanjing University of Technology | And 4 more authors.
Chemical Communications | Year: 2014

A novel AIE-active boron-difluoride complex (PTZ) was synthesized which exhibits multi-stimuli responsive characteristics. Its colours and emissions can be switched by mechanical grinding, organic solvent vapours and acid/base vapours. This complex can be utilized in data encryption and decryption based on the protonation-deprotonation effect. This journal is © the Partner Organisations 2014.


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.


Zhu R.,China University of Mining and Technology | Zhou J.,Nanjing University of Technology | Jiang H.,Nanjing University of Technology | Zhang D.,Shanghai Institute of Applied Mathematics and Mechanics
Mechanics of Materials | Year: 2012

Compared with the coarse-grained counterpart, nanocrystalline (NC) metals have higher strength simultaneously with a decrease in ductility, strain localization is a main factor contributed to the early failure of NC metals during plastic deformation. This work deals with the study of shear banding in fully dense electrodeposited NC Ni sheet with sample dimensions at tens of millimeters under quasi-static uniaxial tensile load through the use of a strain gage calculated by digital image correlation technique. Shear band nucleation, broadening process and failure point were recognized. It is identified that maximum shear strain happens in the middle of the shear band where crack initiates first in this experiment. This indicates that the shear banding induces the failure of the NC Ni sample. Meanwhile, physical characteristics of the shear band, such as inclination and width of single full-developed shear band, were determined quantitatively. The results show that the inclination of shear band is about 63°, as well as the width of shear band is in sub-micrometer range. To investigate the micro-mechanisms during the shear banding process in the NC Ni sample, in situ tensile testing in a transmission electron microscope was conducted, the results suggest that grain boundary migration and grain coalescence are the main carriers during the propagation of shear band. © 2012 Elsevier Ltd. All rights reserved.


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 D.,Nanjing University of Technology | Ming L.,JA SOLAR | Huang M.,JA SOLAR | Zhang Z.,JA SOLAR | And 2 more authors.
Journal of Crystal Growth | Year: 2014

An approach to grain control using seed-assisted growth in directional solidification (DS) is reported in this paper. Proper multi-crystalline silicon seeds at the bottom of the crucible provided numerous fine nucleation points for the controlled grain growth in an optimized hot-zone. Low dislocation density was observed with large numbers of uniform small grains in the silicon ingot, although the grain size increased with crystal growth. Crystals produced using seed-assisted growth showed a higher and more uniform minority carrier lifetime with a much lower dislocation multiplication rate. A higher average solar cell conversion efficiency of about 0.5% in absolute value was obtained in the seed-assisted grown silicon in comparison with that in the seedless silicon under the same cell fabrication process. © 2013 Published by Elsevier B.V.


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.


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.


Xu J.,Huaiyin Normal University | He B.,Nanjing University of Technology | Wu B.,Nanjing University of Technology | Wang B.,Nanjing University of Technology | And 2 more authors.
Bioresource Technology | Year: 2014

A cellulase-producing fungus was isolated from chemically polluted microhabitats by [Amim][Cl] enrichment and identified as Aspergillus fumigatus. The maximum activity of the cellulase in 30% (v/v) ionic liquids (ILs) was detected in [Emim][DMP], [Amim][Cl] and [Emim][MA] as 127%, 111% and 109%, respectively, of its activity in buffer, suggesting its superior performance in high concentration ILs. Strikingly, although its initial activity varied in each IL, its half-life was longer in most ILs than in buffer, evidence of a high conformational stability of the enzyme that is essential for maintaining the remaining activity in relevant media. It noteworthy that 1-3. M NaCl can activate the cellulase somewhat. More gratifyingly, a compatible IL-cellulase system based on the cellulase was developed, and its use significantly improved the saccharification rate of rice straw from 53% to 88% versus the control, demonstrating its potential for efficient transformation of lignocellulose to glucose in a single-step process. © 2014 Elsevier Ltd.


Sun L.-B.,Nanjing University of Technology | Liu X.-Q.,Nanjing University of Technology | Zhou H.-C.,Texas A&M University
Chemical Society Reviews | Year: 2015

Mesoporous solid bases are extremely desirable in green catalytic processes, due to their advantages of accelerated mass transport, negligible corrosion, and easy separation. Great progress has been made in mesoporous solid bases in the last decade. In addition to their wide applications in the catalytic synthesis of organics and fine chemicals, mesoporous solid bases have also been used in the field of energy and environmental catalysis. Development of mesoporous solid bases is therefore of significant importance from both academic and practical points of view. In this review, we provide an overview of the recent advances in mesoporous solid bases, which is basically grouped by the support type and each category is illustrated with typical examples. Cooperative catalysts derived from the incorporation of additional functionalities (i.e. acid and metal) into mesoporous solid bases are also included. The fundamental principles of how to design and fabricate basic materials with mesostructure are highlighted. The mechanism of the formation of basic sites in different mesoporous systems is discussed as well. This journal is © The Royal Society of Chemistry.

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