text:
East China University of Science and Technology is a research university located in Shanghai, China. Originally established as a institution highly specialized in the field of chemistry, it has evolved into a comprehensive university that covers all academic disciplines and offers a large variety of majors. The school encompasses two campuses and a science park in the Xuhui, Fengxian and Jinshan districts of Shanghai. Wikipedia.
Shao X.,University of California at Berkeley |
Shao X.,East China University of Science and Technology |
Swenson T.L.,University of California at Berkeley |
Casida J.E.,University of California at Berkeley
Journal of Agricultural and Food Chemistry | Year: 2013
Cycloxaprid (CYC) is a novel neonicotinoid prepared from the (nitromethylene)imidazole (NMI) analogue of imidacloprid. In this study we consider whether CYC is active per se or only as a proinsecticide for NMI. The IC50 values (nM) for displacing [3H]NMI binding are 43-49 for CYC and 2.3-3.2 for NMI in house fly and honeybee head membranes and 302 and 7.2, respectively, in mouse brain membranes, potency relationships interpreted as partial conversion of some CYC to NMI under the assay conditions. The 6-8-fold difference in toxicity of injected CYC and NMI to house flies is consistent with their relative potencies as in vivo nicotinic acetylcholine receptor (nAChR) inhibitors in brain measured with [3H]NMI binding assays. CYC metabolism in mice largely involves cytochrome P450 pathways without NMI as a major intermediate. Metabolites of CYC tentatively assigned are five monohydroxy derivatives and one each of dihydroxy, nitroso, and amino modifications. CYC appears be a proinsecticide, serving as a slow-release reservoir for NMI with selective activity for insect versus mammalian nAChRs. © 2013 American Chemical Society. Source
Singh A.,Wilmer Eye Institute |
Zhan J.,Wilmer Eye Institute |
Ye Z.,East China University of Science and Technology |
Elisseeff J.H.,Wilmer Eye Institute
Advanced Functional Materials | Year: 2013
Synthetic polymers are employed to create highly defined microenvironments with controlled biochemical and biophysical properties for cell culture and tissue engineering. Chemical modification is required to input biological or chemical ligands, which often changes the fundamental structural properties of the material. Here, a simple modular biomaterial design strategy is reported that employs functional cyclodextrin nanobeads threaded onto poly(ethylene glycol) (PEG) polymer necklaces to form multifunctional hydrogels. Nanobeads with desired chemical or biological functionalities can be simply threaded onto the PEG chains to form hydrogels, creating an accessible platform for users. The design and synthesis of these multifunctional hydrogels are described, structure-property relationships are elucidated, and applications ranging from stem cell culture and differentiation to tissue engineering are demonstrated. Poly(ethylene glycol) is used to create synthetic hydrogel microenvironments for cells, but the ether backbone lacks sites for functionalization. Here, supramolecular chemistry is applied to create modular hydrogels using α-cyclodextrins modified with biological and chemical functional groups with independently controlled crosslinking densities designed to direct stem cell functions. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Niu Y.,East China University of Science and Technology |
Ho D.W.C.,City University of Hong Kong
Journal of the Franklin Institute | Year: 2012
This paper considers the problem of sliding mode control for discrete-time stochastic systems with parameter uncertainties and state-dependent noise perturbation. An integral-like sliding surface is chosen and a discrete-time sliding mode controller is designed. The key feature in this work is that both the reachability of the quasi-sliding mode and the stability of system states are simultaneously analyzed, due to the existence of state-dependent noise perturbation. By utilizing an Lyapunov function involving system states and sliding mode variables, the sufficient condition for reachability is obtained. Finally, numerical simulation results are provided. © 2011 The Franklin Institute. Published by Elsevier Ltd. All rights reserved. Source
Switching off FRET by analyte-induced decomposition of squaraine energy acceptor: A concept to transform 'turn off' chemodosimeter into ratiometric sensors
Yu H.,Dalian University of Technology |
Fu M.,Dalian University of Technology |
Xiao Y.,Dalian University of Technology |
Xiao Y.,East China University of Science and Technology
Physical Chemistry Chemical Physics | Year: 2010
FRET cassette-type sensors, SN-1 and SN-2, which contain two naphthalimide donors and a squaraine acceptor, have been developed on the concept of switching off FRET through removing the spectral overlap by the analyte-induced decompositions of acceptor chromophore. SN-2 shows sensitive responses to fluoride anion and cyanide through both naked-eye detectable colour changes and ratiometric fluorescence changes. As the first example, SN-2 confirms that transformation of the common 'turn-off' chemodosimeter into ratiometric sensors can be realized conveniently based on the novel 'switching FRET off' approach. © 2010 the Owner Societies. Source
Qian J.,University of Amsterdam |
Qian J.,East China University of Science and Technology |
Brouwer A.M.,University of Amsterdam
Physical Chemistry Chemical Physics | Year: 2010
Photophysical properties of the organocatalyst cupreidine (CPD) and its chromophoric building block 6-hydroxyquinoline (6HQ) in protic and nonprotic polar solvents (methanol and acetonitrile) were investigated by means of UV-vis absorption, and steady state and time resolved fluorescence spectroscopy. The effects of the catalytically relevant interactions with electrophilic and hydrogen bonding agents (p-toluene sulfonic acid and water) on their spectral characteristics were studied. In neutral CPD in acetonitrile, quenching of fluorescence occurs due to electron transfer from the quinuclidine nitrogen to the excited quinoline chromophore. Protonation suppresses this process, while complexation with water leads to enhanced excited state proton transfer from the 6′-OH group to the quinuclidine nitrogen, and emission occurs from the anionic form of the chromophore. The weakly emitting zwitterionic form of the hydroxyquinoline chromophore is readily formed in methanol, but not in acetonitrile. © the Owner Societies 2010. Source
Wanga X.,East China University of Science and Technology |
Zhou K.,Nanyang Technological University
Mechanics of Materials | Year: 2012
We study the interaction of a screw dislocation with a multicoated circular inclusion. For given geometric parameters of an N-phase circular inclusion, in which a circular inclusion is bonded to the surrounding matrix through N-2 coaxial coatings, we can properly design the N-1 mismatch parameters of the composite so that there exist N-2 equilibrium positions for the screw dislocation. The designed multicoated inclusion can be considered as a near-cloaking structure for the screw dislocation at these equilibrium positions. © 2012 Elsevier Ltd. All rights reserved. Source
Wang Y.,East China University of Science and Technology |
Shen N.,Soochow University of China
Renewable and Sustainable Energy Reviews | Year: 2016
Constrained by the dual mission of supporting industrial growth and reducing emissions, China's traditional, emission reduction-oriented environmental policies unavoidably face a dilemma. This study adopts the GML index to calculate China's industrial productivity by considering environmental factors. In addition, based on the assumption of industry heterogeneity, the author examines the non-linear relationship between China's environmental regulation and environmental productivity and calculated the optimal regulation environment for industries. According to this study, when impact of undesirable outputs (pollutant emissions) is considered, environmental regulation and environmental productivity are positively correlated, which to some degree validates the Porter Hypothesis. At present, environmental regulation has significant positive effects on clean production industries but shows a lag effect on pollution-intensive industries. The degree of environmental regulation and environmental productivity show an "inverted U"-shaped relation and display three thresholds. It should be noted, however, that the relationship between regulation and productivity may vary across industries. These findings have clear policy implications: rather than continually increasing the level of environmental regulation, the government should establish standards for individual industries that emphasize flexibility. © 2016 Elsevier Ltd. Source
Wang X.,East China University of Science and Technology
Lecture Notes in Electrical Engineering | Year: 2013
In Gas Tungsten Arc Welding (GTAW) process, weld pool contains information that can be used to establish process model, realize desired penetration control and study the weld pool characteristic. Hence, various sensing methods are used to sense weld pool status. At the same time, many researches are conducted to establish the weld process model, and obtain desired weld process control. In this paper, a three dimensional weld pool sensing system was introduced, and the image processing, weld pool reconstruction results were presented. Then, based on the reconstructed 3D weld pool geometry, an artificial neural network (ANN) model was established to describe the weld pool geometry. Simulation results show that the ANN model can reflect weld pool geometry accurately, which will benefit the GTAW process analysis and control. © 2013 Springer-Verlag Berlin Heidelberg. Source
Gong J.,North Dakota State University |
Liang J.,East China University of Science and Technology |
Sumathy K.,North Dakota State University
Renewable and Sustainable Energy Reviews | Year: 2012
The prosperity of human society largely relies on safe energy supply, and fossil fuel has been serving as the most reliable energy source. However, as a non-renewable energy source, the exhaustion of fossil fuel is inevitable and imminent in this century. To address this problem, renewable energy especially solar energy has attracted much attention, because it directly converts solar energy into electrical power leaving no environment affect. In the past, various photovoltaic devices like organic, inorganic, and hybrid solar cells were fabricated in succession. In spite of high conversion rate of silicon based solar cells, the high module cost and complicated production process restricted their application solely to astronautic and aeronautic technology. For domestic and other commercial applications, research has been focused on organic solar cells for their inherent low module cost and easy fabrication. In addition, organic solar cells have their lightweight and flexibility advantage over conventional silicon-based crystalline solar cells. Among all the organic solar cells, dye-sensitized solar cells (DSSCs) are the most efficient and easily implemented technology. Here, this study examines the working principle, present development and future prospectus for this novel technology. © 2012 Elsevier Ltd. Source
Lin Y.,Hunan University |
Bao L.,East China University of Science and Technology |
Wei Y.,Fudan University
IEEE Transactions on Automatic Control | Year: 2010
In this technical note, we investigate the numerical solution of the projected generalized Sylvester equations via a matrix sign function method. Such equations arise in stability analysis and control problems for descriptor systems including model reduction based on balanced truncation. Unlike the classical matrix sign function iteration, we propose a modification of the matrix sign function method that converges quadratically for pencils of arbitrary index. Numerical experiments report the effectiveness of the modified method. © 2006 IEEE. Source
A naphthalimide-based bifunctional fluorescent probe for the differential detection of Hg2+ and Cu2+ in aqueous solution
Huang C.-B.,East China Normal University |
Li H.-R.,Futian Second Peoples Hospital |
Luo Y.,East China University of Science and Technology |
Xu L.,East China Normal University
Dalton Transactions | Year: 2014
A novel fluorescent probe NPM based on naphthalimide was designed and synthesized. Interestingly, NPM exhibited highly selective fluorescence turn-on for Hg2+ and turn-off for Cu2+ in aqueous solution (10 mM HEPES, pH 7.5). Its fluorescence intensity enhanced in a linear fashion with the concentration of Hg2+ and decreased in a nearly linear fashion with the concentration of Cu2+. Thus NPM could be potentially used for the quantification of Hg2+ and Cu2+ in aqueous solution. A series of model compounds were rationally designed and synthesized in order to explore the sensing mechanisms and binding modes of NPM with Hg2+ and Cu2+. This journal is © the Partner Organisations 2014. Source
Niu Y.,East China University of Science and Technology |
Ho D.W.C.,City University of Hong Kong |
Ho D.W.C.,Nanjing University of Science and Technology
Automatica | Year: 2014
A stabilizing controller designed without considering quantization may not be effectively implemented for the systems with quantized information due to quantization errors. Hence, an interesting issue is how to design the quantizer such that the desired system performance can be still attained by the above controller. In this work, a new control strategy with on-line updating the quantizer's parameter is proposed. This scheme may ensure the controlled system to attain the same dynamic performance, H→ disturbance attenuation level, as the one without signal quantization. A practical adjusting rule on quantizer's parameter is proposed such that the state-dependent parameter is available on both sides of encoder/decoder. Finally, some numerical examples have been provided to illustrate the present control scheme. © 2014 Elsevier Ltd. Source
Zhu L.,Nanyang Technological University |
Yan H.,Nanyang Technological University |
Nguyen K.T.,Nanyang Technological University |
Tian H.,East China University of Science and Technology |
Zhao Y.,Nanyang Technological University
Chemical Communications | Year: 2012
An effective self-assembly route for construction of Pt(ii)-bridged [3]rotaxane functionalized gold nanoparticles was developed through a stepwise introduction of Pt(ii) coordination and gold-thiol binding in turn. The sequential self-assembly process can be quantitatively controlled and directly monitored by the naked eye. © The Royal Society of Chemistry 2012. Source
Output feedback adaptive neural control for a class of non-affine non-linear systems with a dynamic gain observer
Du H.,East China University of Science and Technology |
Ge S.S.,National University of Singapore
IET Control Theory and Applications | Year: 2011
Output feedback adaptive neural control is investigated for non-affine non-linear systems with zero dynamics using implicit function theorem, mean value theorem and neural network (NN) parametrisation by exploiting the explicit Lipschitz property of radial basis function NNs for function approximation. The control approach developed is based on non-separation principle design. A new dynamic gain observer is introduced to estimate the unmeasurable states of the system. The observer gain and the neural controller are simultaneously tuned according to output tracking error. With the universal approximation property of NN and the simultaneous parametrisation both for the NN approximation and the controller, restrictive conditions, such as Lipschitz assumption, strictly positive realness condition and contracting assumption are not required. Semi-globally uniformly ultimate boundedness for the steady-state and transient performance is guaranteed, and simulation results demonstrated the effectiveness of the proposed scheme. © 2011 The Institution of Engineering and Technology. Source
Short and long crack data for fatigue of 2024-T3 Al sheets: Binariness of scale segmentation in space and time
Sih G.C.,Lehigh University |
Sih G.C.,East China University of Science and Technology
Fatigue and Fracture of Engineering Materials and Structures | Year: 2014
Pedagogically speaking, crack initiation-growth-termination (IGT) belongs to the process of fracture, the modelling of which entails multiscaling in space and time. This applies to loadings that are increased monotonically or repeated cyclically. Short and long crack data are required to describe IGT for scale ranges from nano to macro, segmented by the SI system of measurement. Unless the data at the nano scale can be connected with the macro, IGT remains disintegrated. The diversity of non-homogeneity of the physical properties at the different scale ranges results in non-equilibrium. These effects dubbed as non-equilibrium and non-homogeneous are hidden in the test specimens and must be realized. They can be locked into the reference state of measurement at the mi-ma scale range by application of the transitional functions and transferred to the nano-micro and macro-large scale ranges. The aim of this work is to convert the ordinary crack length data to those referred to as short cracks that are not directly measurable. All test data are material, loading and geometry (MLG) specific. The results obtained for the 2024-T3 aluminium sheets hold only for the MLG tested. The differences are more pronounced for the short cracks. These effects can be revealed by comparing the incremental crack driving force (CDF) for the ma-mi range ΔSmicromacro, the ma-large range ΔSlargemacro and the na-mi range ΔSnanomicro. The CDF is equivalent to the incremental volume energy density factor (VEDF). The incremental mi-ma CDF is found to be 10-105 kg mm-1 for cracks 3-55 mm long travelling at an average velocity of 10-5 mm s-1. The crack velocity rises to 10-3 mm s-1 when the incremental CDF ΔSmacrolarge is increased to 105-106 kg mm -1, while the crack lengths are 49-260 mm. The crack velocity for the na-mi range of 0.040-0.043 mm slowed down to 10-8 mm s-1, and the incremental CDF ΔSnanomicro reduces further to 10 -8-10-2 kg mm-1. Note that ΔSnanomicro changed several orders of magnitude while the crack advanced from 0.040 to 0.044 mm. Such behaviour is indicative of the highly unstable nature of nanocracks. All results are based on using the transitionalized crack length (TCL). The TCL fatigue crack growth increment Δa is postulated to depend on the incremental CDF ΔS or ΔVEDF. The form invariance of ΔSnanomicro, ΔSlargemacro and ΔSmicromacro is invoked by scale segmentation to reveal the multiscale nature of IGT that is inherent to fatigue crack growth. While the choice of directionality from micro to macro is not the same as that from macro to micro, this difference will not be addressed in this work. © 2013 Wiley Publishing Ltd. Source
Simultaneous iterative method for the derivatives of several eigenpairs of unsymmetric damped systems
Xie H.,East China University of Science and Technology
Mechanical Systems and Signal Processing | Year: 2015
Abstract In this paper, a new iterative method is proposed to calculate a few eigenpair derivatives of damped systems. The proposed method simultaneously computes the derivatives of several simple eigenvalues and their corresponding eigenvectors. Eigenpair derivatives are directly determined in n-space. Moreover, our method does not require the left eigenvectors. Convergence theory of the proposed method is given. On these grounds, using vector Ïμ-algorithm, acceleration techniques for our method are provided and analyzed. Finally some numerical experiments are reported to show the efficiency of the proposed methods. © 2015 Elsevier Ltd. Source
Wang X.,East China University of Science and Technology
Acta Mechanica | Year: 2012
We consider a circular elastic inclusion embedded in a particular class of harmonic materials subjected to remote uniform stresses. The imperfect interface can be rate dependent as well as rate independent. First, we study the situation in which both rate-depending slip and diffusional relaxation are present on the sharp inclusion-matrix imperfect interface. It is found that in general, the internal Piola stresses within the inclusion are spatially non-uniform and decay with two relaxation times. Interestingly, the average mean Piola stress within the circular inclusion is time independent. Some extreme cases for the imperfect interface are discussed in detail. Particularly, we find a simple condition leading to internal uniform Piola stresses that decay only with a single relaxation time. Second, we investigate a rate-independent spring-type imperfect interface on which normal and shear tractions are proportional to the corresponding displacement jumps. It is found that in general, the internal Piola stresses are intrinsically non-uniform. A special kind of the spring-type interface leading to internal uniform Piola stresses is also found. © 2011 Springer-Verlag. Source
Sih G.C.,Lehigh University |
Sih G.C.,East China University of Science and Technology
Physical Mesomechanics | Year: 2013
Scale segmentation of the SI system of measurement has necessitated the use of transitional function for connecting the results of the segmented scales. The state-of-the-art of measurement in the 1800s is reflected by the coarseness of scale segmentation. By up-to-day standard of nanonization, scale refinement is necessary to account for the interactive benefits of multiscaling, the building block of which is dual scaling, say macro-micro or micro-nano. The directional dissimilarity between two adjacent scales, say macro → micro and micro → macro, arises naturally in physical processes. An index Λ is defined to measure the severity of directional dissimilarity that may prevail in the volume energy density factor (VEDF) for macro → micro. A similar index Ω applies to micro → macro. Both A and Ω reflect the combined effects of loading, material and geometry. The macro-micro transition of VEDFmacro can differ from the micro-macro transition of VEDFmicro. The relation between the macrostress intensity factor and VEDFmacro is incompatible with that for the microstress intensity factor and VEDFmicro. The stress intensity factor, a monoscale concept, will not hold for both the macro- and micro-scale. To begin with, the units may differ. The same holds for the volume energy density factor. The irreconcilability can be resolved by an argument of dimensional compatibility, provided that the agreement is to preserve the monoscale definitions. These considerations call for a scrutiny of the crack growth data whose scatter may be contributed by the directional effects of scale transition. © 2013 Pleiades Publishing, Ltd. Source
Fan C.,Shanghai JiaoTong University |
Qi K.,East China University of Science and Technology |
Xia X.-X.,Shanghai JiaoTong University |
Zhong J.-J.,Shanghai JiaoTong University
Bioresource Technology | Year: 2013
For economically feasible lignocellulosic ethanol production, it is crucial to obtain a robust strain and develop an efficient fermentation process. An earlier-screened yeast strain Pichia guilliermondii was adapted to corncob residues (CCR) hydrolysate and used for high titer ethanol production without any detoxification or external nutrient supplementation. With an optimized fed-batch strategy, the maximum ethanol titer and productivity reached 56.3g/l and 0.47gl-1h-1, respectively. To further increase the ethanol productivity, the fed-batch process was repeated three times with cell reuse, and the maximum ethanol titer and productivity reached 51.2g/l and 1.11gl-1h-1, respectively. The results demonstrated that the combination of fed-batch with repeated fermentation was effective in improving the fermentation efficiency and achieving high ethanol productivity from CCR. The reported system is considered promising for commercial production of bioethanol from biomass hydrolysate in the future. © 2013 Elsevier Ltd. Source
Sih G.C.,Lehigh University |
Sih G.C.,East China University of Science and Technology
Theoretical and Applied Fracture Mechanics | Year: 2011
The energy release rate criterion, being mono scale by definition, is incompatible with the failure behavior of solids that are inherently dual, if not, multiscale. Time span of reliability is scale sensitive and can be addressed with consistency only by use of transitional functions that are designed to transform a function from one scale to another. A pseudo transitional energy release rate G * is defined to address the cross-scaling properties of energy release rate. The reliability of such a function is found to fall quickly when the scale range deviates from that of micro-macro. In general, the time span of reliability based on G shortens considerably within the nano-micro and pico-nano scale ranges, resulting in fast turnover of system usability. Prediction accuracy tends to be scale range specific. Stress or strain based criteria are also mono scale. They may be adequate for some situations at the macroscopic scale, but can be ambiguous for multiscale problems. These situations are analyzed by application of the principle of least variance in conjunction with the R-integrals. Accelerated test data for the equivalent of 20. years' fatigue crack growth in 2024-T3 aluminum panels were analyzed using the mutliscale reliability model. A time span plateau within the micro-macro range is from 8 to 17. years. This corresponds to the reliable portion of prediction, while the terminal 3. years are regarded as unreliable. A similar time span plateau were also found from 4 to 6. years within the nano-micro scale range. And an even smaller plateau hovering around 1.2. years were found for the pico-nano scale range. Time span of reliable prediction narrows with down sized scale range. The overlapping ends of the scale ranges are rendered unreliable as anticipated. These regions can be suppressed by the addition of meso scale ranges. Reference can be made to past discussions related to multiscaling and mesomechanics. © 2011. Source
Tian H.,East China University of Science and Technology
Angewandte Chemie - International Edition | Year: 2010
(Figure Presented) En route to bits and bytes: The integration of complex logic functions within individual molecules allows data processing at the molecular level, as demonstrated by recently reported molecular encoder and decoder devices. This research on decision-making molecules has great potential for future applications and more complex computing on a functional unimolecular platform. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Hierarchical porous carbons prepared from direct coal liquefaction residue and coal for supercapacitor electrodes
Zhang J.,Dalian University of Technology |
Jin L.,Dalian University of Technology |
Jin L.,East China University of Science and Technology |
Cheng J.,Dalian University of Technology |
Hu H.,Dalian University of Technology
Carbon | Year: 2013
Hierarchical porous carbons were prepared from a coal liquefaction residue (CLR) and two coals, Shenhua (SH) coal with low and Shengli (SL) coal with high ash content, by KOH activation with the addition of some additives, and used as the electrode for supercapacitors. Two metal oxides (MgO and Al 2O3) and three organic materials (sugar, urea and cetyltrimethylammonium bromide) were used as the additives, to investigate their effects on the structure and capacitive performance of the resultant carbons. The results show that the metal oxide and/or its salt formed by the reaction with KOH can serve as space fillers of nanopores in the carbonized carbon, while the gases produced by the decomposition of the organic additive can develop and/or widen some pores. Both help the carbon produced from CLR or the SH coal with low ash content to have additional meso- and macropores, but destroy the structure of the carbon from the SL coal with high ash content. Compared with the carbon without any additive, the optimized hierarchical porous carbon with each additive shows a smaller equivalent resistance, much higher capacitance in a wide range of charge-discharge rates and excellent cycle stability when the carbon was used as supercapacitor electrode. © 2012 Elsevier Ltd. All rights reserved. Source
Zhou X.,Shanghai JiaoTong University |
Zheng J.,Shanghai JiaoTong University |
Wu H.,Shanghai JiaoTong University |
Yang H.,Shanghai JiaoTong University |
And 2 more authors.
Journal of Physical Chemistry C | Year: 2011
Bulk-scale production of individual graphene sheets is still challenging although several methodologies have been developed. We report here a rapid and cost-effective approach to reduction of graphene oxide (GO) using hydroxylamine as a reductant. We demonstrated that the reduction of GO with hydroxylamine could take place quickly under a mild condition, and the as-produced graphene sheet showed high electrical conductivity, fair crystalline state, and admirable aqueous dispersibility without using any stabilizing reagents. A mechanism for removal of epoxide and hydroxyl groups from GO by hydroxylamine has been proposed. Comparing with other reported methods, the reduction of GO with hydroxylamine should be a preferable route to bulk-scale production of the graphene because it is simple, efficient, and cost-effective. © 2011 American Chemical Society. Source
Sun J.-R.,East China University of Science and Technology |
Wu S.-Y.,National Chiao Tung University |
Zhang H.-Q.,University of Lisbon
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013
We study the transport coefficients, including the conductivities and shear viscosity of the nonrelativistic field theory dual to the Lifshitz black brane with multiple U(1) gauge fields by virtue of the gauge/gravity duality. Focusing on the case of double U(1) gauge fields, we systematically investigate the electric, thermal, and thermoelectric conductivities for the dual nonrelativistic field theory. In the large frequency regime, we find a nontrivial power law behavior in the electric alternating current conductivity when the dynamical critical exponent z>1 in (2+1)-dimensional field theory. The relations between this novel feature and the "symmetric hopping model" in condensed matter physics are discussed. In addition, we also show that the Kovtun-Starinets-Son bound for the shear viscosity to the entropy density is not violated by the additional U(1) gauge fields and dilaton in the Lifshitz black brane. © 2013 American Physical Society. Source
Zhang H.,Tongji University |
Zhang H.,City University of Hong Kong |
Feng G.,City University of Hong Kong |
Feng G.,Nanjing University of Science and Technology |
And 2 more authors.
IEEE Transactions on Industrial Electronics | Year: 2014
This paper studies the consensus problem of linear multi-agent systems via observer-based event-triggered control. Two novel observer-based event-triggered control schemes, one centralized and the other distributed, are developed. It is shown that under the proposed control protocols, consensus can be reached if the underlying communication graph of the MAS is connected. An example is finally presented to illustrate the effectiveness of the proposed control methods. © 1982-2012 IEEE. Source
Niu Y.,East China University of Science and Technology |
Ho D.W.C.,City University of Hong Kong |
Li C.W.,City University of Hong Kong
IEEE Transactions on Fuzzy Systems | Year: 2010
This paper deals with the filtering problem for discrete-time fuzzy stochastic systems with sensor nonlinearities. There exist time-varying parameter uncertainties and random noise depending on state and external-disturbance. The characteristic of nonlinear sensor is handled by a decomposition method. By means of the parallel distributed compensation technique, the design method of the robust ℋ∞ filter is presented. Sufficient conditions for the stochastic stability of the filtering error systems are derived such that the filter parameters can be explicitly obtained. Simulation results are given to illustrate the proposed method. © 2010 IEEE. Source
Ohta T.,Kyushu University |
Liu J.-G.,Kyushu University |
Liu J.-G.,East China University of Science and Technology |
Naruta Y.,Kyushu University
Coordination Chemistry Reviews | Year: 2013
Recent advances in understanding the structural properties of mononuclear heme-peroxo intermediates are reviewed. The peroxo adducts of hemes are pivotal intermediates generated in the active site of heme enzymes, which catalyze dioxygen activation. The transient nature of the peroxo intermediates under physiological conditions makes isolation and spectroscopic characterizations difficult. Thus, our aim was to generate and capture peroxo intermediates using specifically designed porphyrin complexes at low temperatures, where the cryogenic spectroscopic analyses were performed. Our studies revealed the first reliable resonance Raman (RR) evidence for heme-peroxo intermediate models and provided important insight into the structural mechanism of side-on and end-on (hydro)peroxo-bound hemes. © 2012 Elsevier B.V.. Source
Li F.,Tongji University |
Li F.,East China University of Science and Technology |
Sun J.,Tongji University
Neural Networks | Year: 2012
This paper investigates the controllability and optimal control of a temporal Boolean network, where the time delays are time variant. First, using the theory of semi-tensor product of matrices, the logical systems can be converted into a discrete time variant system. Second, necessary and sufficient conditions for the controllability via two types of controls are provided respectively. Third, optimal control design algorithms are presented. Finally, examples are given to illustrate the proposed results. © 2012 Elsevier Ltd. Source
Liu Y.,University of California at Riverside |
Zhao S.,East China University of Science and Technology |
Wu J.,University of California at Riverside
Journal of Chemical Theory and Computation | Year: 2013
We report a site density functional theory (SDFT) based on the conventional atomistic models of water and the universality ansatz of the bridge functional. The excess Helmholtz energy functional is formulated in terms of a quadratic expansion with respect to the local density deviation from that of a uniform system and a universal functional for all higher-order terms approximated by that of a reference hard-sphere system. With the atomistic pair direct correlation functions of the uniform system calculated from MD simulation and an analytical expression for the bridge functional from the modified fundamental measure theory, the SDFT can be used to predict the structure and thermodynamic properties of water under inhomogeneous conditions with a computational cost negligible in comparison to that of brute-force simulations. The numerical performance of the SDFT has been demonstrated with the predictions of the solvation free energies of 15 molecular analogs of amino acid side chains in water represented by SPC/E, SPC, and TIP3P models. For theTIP3P model, a comparison of the theoretical predictions with MD simulation and experimental data shows agreement within 0.64 and 1.09 kcal/mol on average, respectively. © 2013 American Chemical Society. Source
Scalability and homogenization of transitional functions: Effects of non-equilibrium and non-homogeneity
Sih G.C.,Lehigh University |
Sih G.C.,East China University of Science and Technology
Theoretical and Applied Fracture Mechanics | Year: 2014
Mono-scale functions refer to the individual scale range of the SI system of measurement. Coarseness of the segmented scale was dictated by state-of-the-art of technology at that time. By to-day's standard, non-equilibrium and non-homogeneity (NENH) are first order considerations whereby scales must be refined to include micro, nano and pico effects. The conventional technology applies to monoscaling, confined to equilibrium and homogeneity (E&M). Their conversion to multiscaling requires the use of transitional functions. The ultra high strength and light weight structural materials rely on the absorption of energy at more than one scale. For considerations are effects at microscopic, nanoscopic and picoscopic scales.The irony is that NENH are subject to eventual homogenization for otherwise the multiscale effects could not be transferred to improve and modify the monoscale rules in practices. To this end, additional Postulate and Corollary are needed to account for scale directionality of energy transfer, prevalent to NENH. Direction-dependency differentiates the transition of macro. →. micro and micro. →. macro. Transitional functions are not the same when they traverse up and down the scale. Homogenization averages out NENH effects such that corrections may be applied to monoscaling.Transitional functions can lock-in the load, material and geometry effects of the macro-micro test data to produce the nano-pico data. This is related to the obtainment of small crack data from large crack test data. To this end, the volume energy density factor (VEDF) or the volume energy density (VED) can be used as the transitional functions as a form-invariant criterion such that multiscale effects can be used to correct and modify monoscale results. When NENH effects are highly localized and cannot be averaged out, the time rate of VEDF and VED or the equivalent of the power energy density must be used.The scalar correction for NENH is derived for the macro-micro cracking of a line crack subject to the combined effects of loading, material and geometry. Two correction factors Λ and Ω are used, one for macro. →. micro and another for micro. →. macro. The outcome can be checked by results for crack length and/or crack growth rate. © 2013 Elsevier Ltd. Source
Sih G.C.,Lehigh University |
Sih G.C.,East China University of Science and Technology
Theoretical and Applied Fracture Mechanics | Year: 2011
Multiscale reliability places priority on the shifting of space-time scale while dual-scale reliability concentrates on time limits. Both can be ranked by applying the principle of least variance, although the prevailing criteria for assessment may differ. The elements measuring reliability can be ideally assumed to be non-interactive or interactive as a rule. Different formulations of the latter can be adopted to yield weak, strong, and mixed reliability depending on the application. Variance can also be referred to the average based on the linear sum, the root mean square, or otherwise. Preference will again depend on the physical system under consideration. Different space-time scale ranges can be chosen for the appropriate time span to failure. Up to now, only partial validation can be made due to the lack of lower scale data that are generated theoretically. A set of R-integrals is defined to account for the evolution effects by way of the root functions from Ideomechanics. The approach calls for a " pulsating mass" model that can connect the physical laws for the small and large bodies, including energy dissipation at all scale level. Non-linearity is no longer an issue when characterization of matter is made by the multiscaling of space-time. Ordinary functions can also be treated with minor modifications. The key objective is not to derive new theories, but to explain the underlying physics of existing test data, and the reliability of diversified propositions for predicting the time span to failure. Present and past investigations have remained at the micro-macro or mi-ma scale range for several decades due to the inability to quantify lower scale data. To this end, the available mi-ma fatigue crack growth data are used to generate those at the na-mi and pi-na scale ranges. Reliability variances are computed for the three different scale ranges, covering effects from the atomic to the macroscopic scale. They include the initial crack or defect length and velocities. Specimen with large initial defects are found to be more reliable. This trend also holds for each of the na-mi and pi-na scale range. Also, large specimen data had smaller reliability variances than the smaller specimens making them more reliable. Variances for the nano- and pico-scale range had much more scatter and were diversified. Uncertainties and un-reliabilities at the atomic and sub-atomic scale are no doubt related, although their connections remain to be found. Reliability with high order precisions are also defined for multi-component systems that can involve trillions of elements at the different scale ranges. Such large scale computations are now within reach by the advent of super-speed computers, especially when reliability, risk, and among other factors may have to be considered simultaneously. © 2011 Elsevier Ltd. Source
Ordered mesoporous CeO2-TiO2 composites: Highly efficient photocatalysts for the reduction of CO2 with H2O under simulated solar irradiation
Wang Y.,University of Shanghai for Science and Technology |
Li B.,Fudan University |
Zhang C.,Fudan University |
Cui L.,University of Shanghai for Science and Technology |
And 3 more authors.
Applied Catalysis B: Environmental | Year: 2013
Ordered mesoporous CeO2-TiO2 composites with 2D hexagonal structure and varied compositions were synthesized through a nanocasting route using ordered mesoporous SBA-15 as the template. X-ray diffraction, nitrogen adsorption-desorption, transmission electron microscopy, X-ray photoelectron spectroscopy and UV-vis diffuse reflectance spectra analysis techniques were used to characterize the samples. It is observed that the obtained CeO2-TiO2 composites have ordered 2D hexagonal mesostructures with high specific surface area and hierarchical porosity. Introduction of CeO2 species can effectively extend the spectral response from UV to visible area and enhance the surface chemisorbed oxygen of the ordered mesoporous TiO2. Due to the peculiar composition and structural characteristics, these ordered mesoporous CeO2-TiO2 composites exhibited excellent photocatalytic activity in the reduction of CO2 with H2O under simulated solar irradiation. © 2012 Elsevier B.V. Source
Sih G.C.,Lehigh University |
Sih G.C.,East China University of Science and Technology
Theoretical and Applied Fracture Mechanics | Year: 2011
Reliability assures the time span of the physical events to occur on pre-determined path. The time dependent and multi-path process of cell growth and division can vary with a combination of effects that can add, negate, and compensate. Their trade-offs can be hidden in the test data, especially when the spatial-temporal scales are allowed to cross scale ranges. Cell entities consisting of dissolved chemicals are likely to wonder from scale to scale. Interaction of large and small bodies with long and short term effects can be the rule rather than the exception. Cell replication is inherently a multiscale phenomenon. The end results can be affected by the environment in ways that are not always determinable. Ranking the possible outcome by occurrence " reliability" provides a positive guidance. This can be accomplished by using the four root parameters obtained from the theory of Ideomechanics (IDM). They consist of length (size), velocity (growth rate), mass density (quantification), and energy density (life). A set of R-integrals and weighted functions are used and derived by satisfying a set of a posteriori conditions together with the principle of least variance. The general character of the time span of reliability can then be found. The approach has worked for non-living organisms and should apply equally well for living organisms, since the principle of Ideomechanics remains valid from the macroscopic to the picoscopic scale range, covering the genetic events of DNA by the 64 ideograms. It is a matter of identifying causes with effects from the early stages of evolution of organisms. The three scale ranges used are pico-nano, nano-micro, and micro-macro. The possible occurrence of a macroscopic event can thus be predicted by connecting the results on reliability of the three scale ranges. A limited portion of this complete scheme will be considered for demonstration.In what follows, the cell growth characteristics will be explored by analyzing the reliability time spans of cell dividing frequency and fraction, in addition to the cell volume change versus time behavior. The method of approach involves converting one of the " length" root function in Ideomechanics to an ordinary function. A description of the entire process of cell growth will need information on the remaining three root parameters. The triolism (TRLM) of wave-particle-change emphasizes the need to include the local energy dissipation owing to space-time non-homogeneity that was neglected in the dualism (DULM) of wave-particle in quantum mechanics. Two additional laws were discovered: one for space-energy trade-off and one for mass-motion interaction. Their presence were necessary in cellular microbiology. The concept of Newtonian " force" must also be discounted to define a generalized energy-based viscosity in multiscaling such that the true behavior of the cells, organelles, subunits, and adenosine triphosphates (ATPs) can be simulated. Deoxyribonucleic acid molecule (DNAM) will be considered as the exchange unit of chemical elements in KMT and the root parameters in IDM. Discussed are also symptoms of neuron degeneration (NDG) diseases need to be detected before they reaches the irreversible stage. Their occurrence may be related to the improper division of diseased cells and/or DNAs. © 2011. Source
Zhou X.,Shanghai JiaoTong University |
Guo S.,Shanghai JiaoTong University |
Zhang J.,East China University of Science and Technology
ChemPhysChem | Year: 2013
This minireview describes recent progress in solution-processable graphene quantum dots (SGQDs). Advances in the preparation, modification, properties, and applications of SGQDs are highlighted in detail. As one of emerging nanostructured materials, possible ongoing research related to the precise control of the lateral size, edge structure and surface functionality; the manipulation and characterization; the relationship between the properties and structure; and interfaces with biological systems of SGQDs have been speculated upon. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Monochromic red-emitting nonconjugated copolymers containing double-carrier-trapping phosphine oxide Eu3+ segments: Toward bright and efficient electroluminescence
Xu H.,Heilongjiang University |
Zhu R.,Nanjing University of Posts and Telecommunications |
Zhao P.,East China University of Science and Technology |
Huang W.,Nanjing University of Posts and Telecommunications
Journal of Physical Chemistry C | Year: 2011
Two metallopolymers P1 and P2 were prepared by using a novel polymerizable Eu3+ complex Eu(TTA)3VBADPO (EuMA) (TTA = 2-thenoyltrifluoroacetonate) and vinylcarbazole as the monomers in the ratios of 1:99 and 3:97, respectively, in which VBADPO is 2-(diphenylphosphoryl)-N-(2- (diphenylphosphoryl)-4-methoxyphenyl)-4-methoxy-N-(4-vinylbenzyl)aniline as a polymerizable aryl phosphine oxide ligand with a bipolar structure. The copolymers exhibit the excellent optical properties with photoluminescence quantum yield more than 60% in film. Both Gaussian simulation and electrochemical analysis indicated that the Eu3+-complexed segments form double-carrier traps (Eu-trap) in the copolymers with depth of 0.1 eV for the hole and 0.7 eV for the electron. The single-layer spin-coated devices of P1 and P2 realized the pure red emissions from Eu3+ ions. The biggest luminance of 149.1 cd m-2 was achieved, which is the highest among those of electroluminescent (EL) Eu3+-containing copolymers reported so far. The unusual efficiency stability proves the limited concentration quenching and T-T annihilation in P1 and P2 due to the uniform dispersion of emissive Eu3+ chelate moieties in the host matrix. With the high brightness and very stable efficiencies, P1 is favorable among the high-performance Eu3+-containing copolymers. It is also proved that the formation of carrier-traps in the copolymers is effective to improve EL performances. © 2011 American Chemical Society. Source
Guo Z.,Ewha Womans University |
Guo Z.,East China University of Science and Technology |
Park S.,Yonsei University |
Yoon J.,Ewha Womans University |
Shin I.,Yonsei University
Chemical Society Reviews | Year: 2014
Near-infrared (NIR) fluorescent dyes have emerged as promising modalities for monitoring the levels of various biologically relevant species in cells and organisms. The use of NIR probes enables deep photon penetration in tissue, minimizes photo-damage to biological samples, and produces low background auto-fluorescence from biomolecules present in living systems. The number of new analyte-responsive NIR fluorescent probes has increased substantially in recent years as a consequence of intense research efforts. In this tutorial review, we highlight recent advances (2010-2013) made in the development and applications of NIR fluorescent probes. The review focuses on NIR fluorescent probes that have been devised to sense various biologically important species, including ROS/RNS, metal ions, anions, enzymes and other related species, as well as intracellular pH changes. The basic principles involved in the design of functional NIR fluorescent probes and suggestions about how to expand applications of NIR imaging agents are also described. © 2014 The Royal Society of Chemistry. Source
Synthesis of a highly Zn 2+-selective cyanine-based probe and its use for tracing endogenous zinc ions in cells and organisms
Guo Z.,Ewha Womans University |
Guo Z.,East China University of Science and Technology |
Kim G.-H.,Yonsei University |
Yoon J.,Ewha Womans University |
Shin I.,Yonsei University
Nature Protocols | Year: 2014
The zinc ion has a key role in a variety of physiological and pathological processes. As a consequence, the development of sensitive and reliable methods to monitor the presence of zinc ions in cells and organisms is of great importance to biological research and biomedical applications. This protocol describes detailed procedures for the five-stage synthesis of a zinc ion-selective, cyanine-based fluorescent probe, CTMPA, from 2,6- bis(hydroxymethyl)pyridine. In addition, we describe its applications in the detection of Zn 2+ released during apoptosis in cells and endogenous Zn 2+ in living zebrafish. Notably, the use of CTMPA enabled our research group to monitor for the first time the presence of zinc ions in neuromasts of zebrafish via fluorescence. The approximate time frame for the synthesis of CTMPA is 4-5 d, and for its use in bioimaging is 8-10 h for cells and 2 h for zebrafish. © 2014 Nature America, Inc. Source
Hu G.,East China University of Science and Technology |
Yu W.,Shanghai Normal University
International Journal of Food Sciences and Nutrition | Year: 2013
The objective of this study was to investigate the possibility of using hemicellulose from rice bran to scavenge cholesterol and bile acid in vitro study. This paper demonstrates that rice bran hemicellulose A (RBHA), rice bran hemicellulose B (RBHB) and rice bran hemicellulose C (RBHC) have the potential for binding cholesterol and bile acid. The quantity of cholesterol and bile acid bound varies from one rice bran fibre to another. As it can be inferred from the results of the study, RBHB was characterized by the highest capacity for cholesterol binding, followed by RBHC and RBHA. Binding of cholesterol and bile acid to rice bran insoluble dietary fibre (RBDF) and cellulose from rice bran was found to be poor. Lignin from rice bran was the least active fraction for binding cholesterol and bile acid. This confirms that the RBHB preparation from defatted rice bran has great potential in food applications, especially in the development of functional foods. © 2012 Informa UK, Ltd. Source
Zhang Z.,East China University of Science and Technology |
Hao S.Y.,Lanzhou Jiaotong University |
Liew K.M.,City University of Hong Kong |
Cheng Y.M.,Shanghai University
Engineering Analysis with Boundary Elements | Year: 2013
In this paper, we derive an improved element-free Galerkin (IEFG) method for two-dimensional linear elastodynamics by employing the improved moving least-squares (IMLS) approximation. In comparison with the conventional moving least-squares (MLS) approximation function, the algebraic equation system in IMLS approximation is well-conditioned. It can be solved without having to derive the inverse matrix. Thus the IEFG method may result in a higher computing speed. In the IEFG method for two-dimensional linear elastodynamics, we employed the Galerkin weak form to derive the discretized system equations, and the Newmark time integration method for the time history analyses. In the modeling process, the penalty method is used to impose the essential boundary conditions to obtain the corresponding formulae of the IEFG method for two-dimensional elastodynamics. The numerical studies illustrated that the IEFG method is efficient by comparing it with the analytical method and the finite element method. © 2013 Elsevier Ltd. All rights reserved. Source
Wang X.,East China University of Science and Technology |
Gao X.-L.,Texas A&M University
Zeitschrift fur Angewandte Mathematik und Physik | Year: 2011
The stress field inside a two-dimensional arbitrary-shape elastic inclusion bonded through an interphase layer to an infinite elastic matrix subjected to uniform stresses at infinity is analytically studied using the complex variable method in elasticity. Both in-plane and anti-plane shear loading cases are considered. It is shown that the stress field within the inclusion can be uniform and hydrostatic under remote constant in-plane stresses and can be uniform under remote constant anti-plane shear stresses. Both of these uniform stress states can be achieved when the shape of the inclusion, the elastic properties of each phase, and the thickness of the interphase layer are properly designed. Possible non-elliptical shapes of inclusions with uniform hydrostatic stresses induced by in-plane loading are identified and divided into three groups. For each group, two conditions that ensure a uniform hydrostatic stress state are obtained. One condition relates the thickness of the interphase layer to elastic properties of the composite phases, while the other links the remote stresses to geometrical and material parameters of the three-phase composite. Similar conditions are analytically obtained for enabling a uniform stress state inside an arbitrary-shape inclusion in a three-phase composite loaded by remote uniform anti-plane shear stresses. © 2011 Springer Basel AG. Source
Luo Y.,Fudan University |
Pan X.,Fudan University |
Yu X.,East China University of Science and Technology |
Wu J.,Fudan University |
Wu J.,CAS Shanghai Institute of Organic Chemistry
Chemical Society Reviews | Year: 2014
Cyclization reactions of alkynes, especially the double carbometallation of alkynes, have drawn much interest from organic chemists because of their high efficiency in the construction of polycycles. Utilizing different nucleophiles or catalytic systems, various efficient strategies to access challenging skeletons have been extensively explored in recent years. In this review, achievements in this field are presented in three major parts (the syn-syn, anti-anti, and syn-anti addition reactions of diynes or two alkyne molecules). Cyclization reactions of diynes initiated by nucleophiles, [2+2+n] cycloaddition, or other processes and reactions, involving two identical or different alkynes are described, which provide facile and reliable approaches to various π systems, medium-sized rings, and even macrocycles. This journal is © The Royal Society of Chemistry. Source
Wang X.,East China University of Science and Technology
International Journal of Advanced Manufacturing Technology | Year: 2014
Automated and robotic welding is now widely used in manufacturing industry. The control of the welding process plays a crucial role in producing quality welds in automated and robotic welding where the assistance from skilled welders is no longer available. In gas tungsten arc welding (GTAW) which is the primary arc welding process for precision joining of metals, the weld pool is the major source of information that can be used to assure the production of desired weld penetration which is the most critical factor determining the weld integrity. To meet this challenge, various sensing technologies have been proposed/studied to sense and obtain the feedback for the weld pool state. This paper summarizes the researches on weld pool state sensing: conventional sensing technologies, vision sensing technology, and multi-sensor information fusion technology, with emphasis on the analysis of three-dimensional vision sensing methods. And three-dimensional vision sensing, multi-sensor technology, intelligent modeling, and effective commercial product development show the future trends of GTAW penetration sensing. © 2014 Springer-Verlag London. Source
Zhang B.,East China University of Science and Technology |
Zhang B.,Beijing Institute of Technology |
Bai C.,Beijing Institute of Technology
Safety Science | Year: 2013
The critical energy of some gaseous fuels and oxygen mixtures at different initial pressure and equivalence ratios are measured based on an experiment system we developed. The determination of direct initiation of detonation is based on the overpressure signal from a pressure transducer. The effective energy responsible for the direct initiation is considered as the first quarter cycle of the current discharge. The effect of initial pressure and equivalence ratio on the critical energy of direct initiation is firstly investigated in some typical gaseous fuel (i.e., C2H2, C2H4, C3H8, H2) and oxygen mixtures. It shows that the relationship between critical energy and initial pressure is inversely exponential and it is 'U' shaped between critical energy and equivalence ratio. The study of the effect of different oxygen concentration and argon dilution on the critical energy of stoichiometric acetylene and oxygen is carried out, the results indicate that oxygen concentration significantly affects the critical energy, and the critical energy increases with increasing amount of argon dilution. This study finally quantitatively research on the detonation hazard parameter (DH) of each stoichiometric mixture. The value of DH in increasing order for the mixtures are as following: C2H2-O2, C2H2-O2-50%Ar, C2H4-O2, C2H2-O2-65%Ar, C2H2-O2-70%Ar, C3H8-O2 and H2-O2, the results also indicate the critical energy is different by orders of magnitude if fuels do not belong to the same group. © 2012 Elsevier Ltd. Source
Zhang W.,University of Bayreuth |
Zhang W.,East China University of Science and Technology |
Muller A.H.E.,University of Bayreuth
Macromolecules | Year: 2010
A click chemistry approach applied in the preparation of telechelic polyhedral oligomeric silsesquioxanes (POSS) containing polymer hybrids by combining with atom transfer radical polymerization (ATRP) was examined. The spectra of 3-propargylcarbonylpropionic chloride (PCPCl) and 3-propargylcarbonylpropionic acid (PCPA) were compared that showed that the broad band from 2225 to 3251 cm -1 disappeared in the spectrum of PCPCl, and a new band appeared at 1785 cm -1, which was assigned to the stretching vibration of carbonyl chloride. The dibromo-terminated polystyrene was synthesized by ATRP using diethyl 2,6-dibromoheptanrdioate as initiator and CuBr/PMDETA as the catalyst. The terminal bromine atoms of polystyrene (PS)-Br2 were easily transformed into azide groups to produce diazido-polystyrene, PS-(N3)2 through nucleophilic substitution. The monobromo-terminated polystyrene (PS-Br) was prepared by using ethyl 2-bromoisobutyrate (EBiB) as initiator. Source
Jiao X.,Hefei University of Technology |
Wang R.,East China University of Science and Technology
International Journal of Non-Linear Mechanics | Year: 2010
A stochastic model of neuronal population with excitatory and inhibitory connections is proposed, where excitatory synaptic dynamics is considered. Oscillatory synchronized firing patterns of a neuronal population by means of firing density are investigated. Numerical simulations using Fokker-Planck equation show that slow inhibitory connection contributes to oscillatory synchronized firing of the neuronal population, and synchronous activity is enhanced due to inhibitory connection. The effect of time delay on the oscillatory synchronized firing in the neuronal population using phase mode is explored. Numerical simulation indicates that short synaptic transmission delay can suppress oscillatory synchronized firing, but this suppression is instable. © 2008 Elsevier Ltd. All rights reserved. Source
Zhao L.,University of Cardiff |
Li Z.,East China University of Science and Technology |
Wirth T.,University of Cardiff
European Journal of Organic Chemistry | Year: 2011
New chiral non-racemic diselenides were prepared and their corresponding selenium electrophiles were used for thestereoselective functionalization of alkenes. The influence of different nucleophiles on the outcome of the selenenylation reaction was studied. New chiral non-racemic diselenides were prepared and their corresponding selenium electrophiles were used for the stereoselective functionalization of alkenes. The influence of different nucleophiles on the outcome of the selenenylation reaction was studied. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Yan H.,East China University of Science and Technology |
Zhang H.,Tongji University |
Meng M.Q.-H.,Chinese University of Hong Kong
Neurocomputing | Year: 2010
This paper deals with the problem of delay-range-dependent robust H∞ control for uncertain systems with time-varying delays and norm-bounded parameter uncertainties. The time delay is assumed to be a time-varying continuous function belonging to a given range. Firstly, some new delay-range-dependent stability and stabilization criteria are proposed by exploiting a new Lyapunov-Krasovskii functional and by making use of novel techniques for time-delay systems. These developed results enjoy much less conservatism than the existing ones due to the introduction of some free weighting matrices and a method to estimate the upper bound of the derivative of Lyapunov functional without ignoring some useful terms that take into account information of the lower and upper bounds for the time delay. Secondly, based on the criteria obtained, a delay-range-dependent criterion for the existence of a memoryless state feedback H∞ controller that ensures asymptotic stability and a prescribed H∞ performance level of the closed-loop system for all admissible uncertainties is proposed in terms of linear matrix inequality (LMI). Numerical examples are provided to demonstrate the effectiveness and benefits of the proposed method. © 2010 Elsevier B.V. All rights reserved. Source
Wang X.,East China University of Science and Technology |
Schiavone P.,University of Alberta
International Journal of Non-Linear Mechanics | Year: 2013
We study the finite plane deformations of a particular harmonic material surrounding an elliptical hole whose boundary incorporates the contribution of surface mechanics. We are particularly interested in the distribution of the Piola hoop stress along the edge of the hole. Surprisingly, in the absence of any external loading, the hoop stress induced solely by the surface effects is identical to that in the corresponding case in a linearly elastic solid. In addition, we show that even in the presence of surface effects, we can nevertheless design a so-called 'harmonic hole' where the Piola mean stress remains constant everywhere in the surrounding solid. In this case, however, the hoop stress is no longer constant along the edge of the elliptical hole due to the contribution from surface energy. © 2013 Elsevier Ltd. Source
Intramolecular C(sp 3)-H bond activation reactions of low-valent cobalt complexes with coordination unsaturation
Mo Z.,CAS Shanghai Institute of Organic Chemistry |
Chen D.,East China University of Science and Technology |
Leng X.,CAS Shanghai Institute of Organic Chemistry |
Deng L.,CAS Shanghai Institute of Organic Chemistry
Organometallics | Year: 2012
Intramolecular C(sp 3)-H bond activation reactions mediated by low-valent cobalt, both Co(I) and Co(0), have been observed in the reactions of the three-coordinate cobalt complex [Co(IMes) 2Cl] (IMes = 1,3-dimesitylimidazol-2-ylidene) with alkylation reagents and sodium amalgam. The reactions with alkylation reagents gave [Co(IMes)(IMes′)(N 2)], featuring a metalated IMes′ anion, whereas the one-electron-reduction reaction afforded [Co(IMes′) 2]. The Co(II) complex can react with CO, isocyanide, and a diazo compound to furnish interesting cobalt complexes bearing functionalized N-heterocyclic carbene ligands. The establishment of these conversions demonstrates the capability of low-valent cobalt with coordination unsaturation to mediate C(sp 3)-H bond activation and functionalization. © 2012 American Chemical Society. Source
Guo Z.,Ewha Womans University |
Guo Z.,East China University of Science and Technology |
Kim G.-H.,Yonsei University |
Shin I.,Yonsei University |
Yoon J.,Ewha Womans University
Biomaterials | Year: 2012
The highly sensitive and selective, cyanine-based Zn2+ fluorescent sensor CTMPA was designed, prepared and utilized to monitor endogenous zinc ions in live cells and organisms. Upon addition of Zn2+ to solutions of CTMPA, an observable blue to light red color change occurs that can be monitored by using UV-vis spectroscopy. Concomitantly, a remarkably hypsochromic shift (ca.140 nm) in the emission maximum of CTMPA takes place from 730 nm to 590 nm. The observations indicate that association of the probe with Zn2+ leads to shortening of the conjugated, π-electron system in the cyanine dye, the phenomenon likely responsible for the large hypsochromic shift observed in emission spectra. Since CTMPA has meritorious features, including a large spectral shift induced by Zn2+, a low fluorescence background and a high sensitivity toward Zn2+, CTMPA was employed to monitor endogeneous zinc ions released during apoptosis and trace intact Zn2+ during zebrafish development. Owing to its low background and high sensitivity, CTMPA serves as the first probe for fluorescence detection of neuromasts in zebrafish. The results obtained from experiments using live cells and organisms suggest that CTMPA will be a highly useful probe in zinc biology studies. The effort has demonstrated that a strategy, which relies on changes in the π-electron conjugation length of cyanine molecules promoted by guest coordination, has great potential for the creation of cyanine-based probes. © 2012 Elsevier Ltd. Source
Li F.,East China University of Science and Technology
International Journal of Systems Science | Year: 2015
In the literatures, to design state feedback controllers to make the response Boolean network synchronise with the drive Boolean network is rarely considered. Motivated by this, feedback control design for the complete synchronisation of two coupled Boolean networks is investigated in this paper. A necessary condition for the existence of a state feedback controller achieving the complete synchronisation is established first. Then, based on the necessary condition, the feedback control law is proposed. Finally, an example is worked out to illustrate the proposed design procedure. © 2015 Taylor & Francis Source
Qin L.X.,East China University of Science and Technology
Chemistry (Weinheim an der Bergstrasse, Germany) | Year: 2011
Quantum dots (QDs) have been widely used for fluorescent imaging in cells. In particular, surface functionalized QDs are of interest, since they possess the ability to recognize and detect the analytes in the surrounding nanoscale environment based on electron and hole transfer between the analytes and the QDs. Here we demonstrate that fluorescence enhancement/quenching in QDs can be switched by electrochemically modulating electron transfer between attached molecules and QDs. For this purpose, a number of redox-active coenzyme Q (CoQ) disulfide derivatives [CoQC(n)S](2) were synthesized with different alkyl chain lengths (n=1, 5, and 10). The system supremely sensitive to NADH (nicotinamide adenine dinucleotide) and superoxide radical (O(2)(.)(-)), and represents a biomimetic electron-transfer system, modeling part of the mitochondrial respiratory chain. The results of our in situ fluorescence spectroelectrochemical study demonstrate that the reduced state of [CoQC(n)S](2) significantly enhanced the fluorescence intensity of CdTe/ZnS QDs, while the oxidized state of the CoQ conjugates quench the fluorescence to varying degrees. Fluorescence imaging of cells loaded with the conjugate QD-[CoQC(n)S](2) displayed strikingly differences in the fluorescence depending on the redox state of the capping layer, thus introducing a handle for evaluating the status of the cellular redox potential status. Moreover, an MTT assay (MTT=3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) proved that the cytotoxicity of QDs was significantly reduced after immobilization by CoQ derivatives. Those unique features make CoQ derivatived QDs as a promising probe to image redox coenzyme function in vitro and in vivo. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Sih G.C.,Lehigh University |
Sih G.C.,East China University of Science and Technology
Theoretical and Applied Fracture Mechanics | Year: 2010
A R-integral is defined to account for the evolution of the root functions from Ideomechanics. They can be identified with, though not limited to, the fatigue crack length or velocity. The choice was dictated by the available validated data for relating accelerated testing to real time life expectancy. The key issue is to show that there exists a time range of high reliability for the crack length and velocity that correspond to the least variance of the time dependent R-integrals. Excluded from the high reliability time range are the initial time span where the lower scale defects are predominant and the time when the macrocrack approaches instability at relatively high velocity. What remains is the time span for micro-macro cracking. The linear sum (ls) and root mean square (rms) average are used to delineate two different types of variance. The former yields a higher reliability in comparison with that for the latter. The results support the scale range established empirically by in-service health monitoring for the crack length and velocity. The principle of least variance can be extended to multiscale reliability analysis and assessment for multi-component and multi-function systems. © 2010 Elsevier Ltd. Source
He L.-W.,East China University of Science and Technology |
Jin Z.-H.,University of Maine, United States
Journal of Thermal Stresses | Year: 2010
In the classical thermo-poroelasticity theory of porous media, local thermal equilibrium between the solid and fluid phases is assumed. In many transient heat conduction/pore pressure diffusion problems, however, the rate of heat transfer between the solid and fluid may not be fast enough to achieve local thermal equilibrium, i.e., the solid and fluid may undergo different temperature variations, which induces additional pore pressure and thermal stresses. This work presents the basic thermo-poroelasticity equations for porous media undergoing local thermal nonequilibrium (LTNE). In the LTNE thermo-poroelasticity theory, the temperatures of solid and fluid phases are governed by the LTNE heat transfer theory. A weighted average of temperatures for the solid and fluid phases is used to formulate the constitutive equations. The theory is subsequently applied to a cylindrical hole in an infinite porous medium subjected to uniform fluid pressure and temperature at the hole boundary. The asymptotic short time solutions of temperature, pore pressure and thermal stresses are obtained using the Laplace transform technique. The numerical results show that the temperature, pore pressure and thermal stresses are significantly influenced by the LTNE effects. Copyright © Taylor & Francis Group, LLC. Source
Dong L.,Hong Kong University of Science and Technology |
Liu P.N.,East China University of Science and Technology |
Lin N.,Hong Kong University of Science and Technology
Accounts of Chemical Research | Year: 2015
ConspectusChemical reactions may take place in a pure phase of gas or liquid or at the interface of two phases (gas-solid or liquid-solid). Recently, the emerging field of "surface-confined coupling reactions" has attracted intensive attention. In this process, reactants, intermediates, and products of a coupling reaction are adsorbed on a solid-vacuum or a solid-liquid interface. The solid surface restricts all reaction steps on the interface, in other words, the reaction takes place within a lower-dimensional, for example, two-dimensional, space. Surface atoms that are fixed in the surface and adatoms that move on the surface often activate the surface-confined coupling reactions. The synergy of surface morphology and activity allow some reactions that are inefficient or prohibited in the gas or liquid phase to proceed efficiently when the reactions are confined on a surface. Over the past decade, dozens of well-known "textbook" coupling reactions have been shown to proceed as surface-confined coupling reactions.In most cases, the surface-confined coupling reactions were discovered by trial and error, and the reaction pathways are largely unknown. It is thus highly desirable to unravel the mechanisms, mechanisms of surface activation in particular, of the surface-confined coupling reactions. Because the reactions take place on surfaces, advanced surface science techniques can be applied to study the surface-confined coupling reactions. Among them, scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS) are the two most extensively used experimental tools. The former resolves submolecular structures of individual reactants, intermediates, and products in real space, while the latter monitors the chemical states during the reactions in real time. Combination of the two methods provides unprecedented spatial and temporal information on the reaction pathways. The experimental findings are complemented by theoretical modeling. In particular, density-functional theory (DFT) transition-state calculations have been used to shed light on reaction mechanisms and to unravel the trends of different surface materials.In this Account, we discuss recent progress made in two widely studied surface-confined coupling reactions, aryl-aryl (Ullmann-type) coupling and alkyne-alkyne (Glaser-type) coupling, and focus on surface activation effects. Combined experimental and theoretical studies on the same reactions taking place on different metal surfaces have clearly demonstrated that different surfaces not only reduce the reaction barrier differently and render different reaction pathways but also control the morphology of the reaction products and, to some degree, select the reaction products. We end the Account with a list of questions to be addressed in the future. Satisfactorily answering these questions may lead to using the surface-confined coupling reactions to synthesize predefined products with high yield. © 2015 American Chemical Society. Source
Wang X.,East China University of Science and Technology |
Zhou K.,Nanyang Technological University
International Journal of Mechanical Sciences | Year: 2014
The Green's functions for an infinite and a semi-infinite Kirchhoff isotropic laminated plate subjected to concentrated forces, concentrated moments, discontinuous displacements and slopes are obtained. The explicit expressions of the three 4×4 real matrices H, L and S for an isotropic laminated plate are derived by using the complex variable formulation recently developed by the authors. Once the Green's functions for an infinite plate are known, those for a semi-infinite plate can be conveniently obtained by using analytical continuation. The image forces on a point dislocation with discontinuous in-plane displacements and slopes due to its interaction with a rigidly clamped edge and a free edge are presented by using the obtained explicit expressions of H and L. Finally, the surface Green's functions of concentrated forces and moments are obtained as a limiting case of the Green's functions for a semi-infinite plate with a free edge. Some interesting features of the surface Green's functions are observed. © 2014 Elsevier Ltd. Source
Three-phase anisotropic elliptical inclusions with internal uniform in-plane and anti-plane stresses
Wang X.,East China University of Science and Technology
Mathematics and Mechanics of Solids | Year: 2016
We study the stress field of a three-phase composite in which an internal elliptical inclusion is bonded to the surrounding matrix through an interphase layer. The linearly elastic materials occupying both the inclusion and the matrix are generally anisotropic, whereas the interphase layer is made of an isotropic elastic material. The two interfaces of the three-phase composite are confocal ellipses. Two conditions are found that ensure that the internal in-plane and anti-plane stress field is uniform. When these conditions are met, the mean stress within the isotropic interphase layer is also uniform. A real form expression of the internal uniform stress field inside the inclusion is derived. Several examples are presented to demonstrate and validate the obtained results. © 2014 SAGE Publications. Source
Vanishing viscosity and Debye-length limit to rarefaction wave with vacuum for the 1D bipolar Navier–Stokes–Poisson equation
Li Y.,East China University of Science and Technology
Zeitschrift fur Angewandte Mathematik und Physik | Year: 2016
In this paper, we consider the one-dimensional (1D) compressible bipolar Navier–Stokes–Poisson equations. We know that when the viscosity coefficient and Debye length are zero in the compressible bipolar Navier–Stokes–Poisson equations, we have the compressible Euler equations. Under the case that the compressible Euler equations have a rarefaction wave with one-side vacuum state, we can construct a sequence of the approximation solution to the one-dimensional bipolar Navier–Stokes–Poisson equations with well-prepared initial data, which converges to the above rarefaction wave with vacuum as the viscosity and the Debye length tend to zero. Moreover, we also obtain the uniform convergence rate. The results are proved by a scaling argument and elaborate energy estimate. © 2016, Springer International Publishing. Source
Fractal kinetic analysis of polymers/nonionic surfactants to eliminate lignin inhibition in enzymatic saccharification of cellulose
Wang Z.,Shanghai JiaoTong University |
Xu J.-H.,East China University of Science and Technology |
Feng H.,University of Illinois at Urbana - Champaign |
Qi H.,Shanghai JiaoTong University
Bioresource Technology | Year: 2011
The profile of enzymatic saccharification of Avicel in the presence and absence of lignin has been described with a fractal kinetic model (Wang and Feng, 2010), in which the retarded hydrolysis rate of enzymatic saccharification of cellulose has been represented with a fractal exponent. The lignin inhibition in the enzymatic saccharification of cellulose is indexed by the increase of fractal exponent, which can not be fully counterbalanced by high cellulase loading due to the high fractal exponent at high cellulase loading. On the contrary, fractal kinetic analysis indicates that an addition of some nonionic surfactant/polymers decrease the fractal exponent to the original values of enzymatic saccharification of Avicel without lignin and the corresponding toxicity of nonionic surfactants/polymers on the consecutive ethanol fermentation strain Saccharomyces cerevisiae is also examined. © 2010 Elsevier Ltd. Source
Multivariate outlier detection based on self-organizing map and adaptive nonlinear map and its application
Yan X.,East China University of Science and Technology
Chemometrics and Intelligent Laboratory Systems | Year: 2011
To facilitate visualizing and detecting outliers in high dimensional complex data, a novel method integrating self-organizing map (SOM) with adaptive non-linear map (ANLM) was proposed for multivariate outlier detection. Firstly, the high dimensional complex data are pre-processed by robust scaling. Secondly, SOM is applied to map the pre-processed data onto the SOM plane to obtain the topology of the high dimensional complex data, and then the 2-dimensional projection plane of the trained SOM plane, on which the data distribution can be visualized easily, is obtained via ANLM. In sequel, based on the 2-dimensional plane and the topology, a quasi-3 d edit rule was proposed to distinguish between the normal data and the outliers in high dimensional complex data. Finally, the proposed multivariate outlier detection was illustrated using synthetic data, two standard benchmark data sets and a real industrial process data. The empirical results show that the outliers in high dimensional complex data are visualized easily on the 2-dimensional plane and effectively detected and eliminated by the quasi-3 d edit rule, and fully demonstrate its satisfactory ability on dealing with outliers in high dimensional complex data. © 2011 Elsevier B.V. Source
Hypoxia-Mediated Increases in l-2-hydroxyglutarate Coordinate the Metabolic Response to Reductive Stress
Oldham W.M.,Harvard University |
Clish C.B.,The Broad Institute of MIT and Harvard |
Yang Y.,East China University of Science and Technology |
Loscalzo J.,Harvard University
Cell Metabolism | Year: 2015
Metabolic adaptation to hypoxia is critical for survival in metazoan species for which reason they have developed cellular mechanisms for mitigating its adverse consequences. Here, we have identified l-2-hydroxyglutarate (L2HG) as a universal adaptive determinant of the hypoxia response. L2HG is a metabolite of unknown function produced by the reduction of mitochondrial 2-oxoglutarate by malate dehydrogenase. L2HG accumulates in response to increases in 2-oxoglutarate, which occur as a result of tricarboxylic acid cycle dysfunction and increased mitochondrial reducing potential. These changes are closely coupled to cellular redox homeostasis, as increased cellular L2HG inhibits electron transport and glycolysis to offset the adverse consequences of mitochondrial reductive stress induced by hypoxia. Thus, L2HG couples mitochondrial and cytoplasmic energy metabolism in a model of cellular redox regulation. © 2015 Elsevier Inc. Source
Wang H.,East China University of Science and Technology |
Kong A.,East China Normal University
Materials Letters | Year: 2014
Fluorine-doped mesoporous carbons (F/Cs) were prepared by a simple hard-template method. The pyrolysis of polytetrafluoroethylene (PTFE) supported on SBA-15 silica at high temperatures resulted in the formation of mesoporous structures with graphitic pore walls. The F/Cs obtained at 1000 °C possessed a surface area of 504 m2 g-1 and a pore size distribution centered at 6.7 nm. Such F/Cs exhibited a comparable catalytic activity for oxygen reduction reaction (ORR) to that of commercial platinum/carbon (Pt/C) catalysts and better stability and methanol-tolerance in alkaline solutions. © 2014 Elsevier B.V. All rights reserved. Source
Wang C.,Nanjing Southeast University |
Li J.,Nanjing Southeast University |
Amatore C.,CNRS PASTEUR Laboratory |
Chen Y.,East China University of Science and Technology |
And 2 more authors.
Angewandte Chemie - International Edition | Year: 2011
Gold and carbon make it together: Gold nanoclusters (GNCs) impregnated onto reduced graphene oxide (RGO) nanosheets cross swiftly across HepG2 hepatocarcinoma cell membranes to alter proteins and DNA and transport anticancer molecular drugs, such as doxorubicin (DOX). Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
A FRET-based ratiometric fluorescent and colorimetric probe for the facile detection of organophosphonate nerve agent mimic DCP
Xuan W.,University of New Mexico |
Cao Y.,University of New Mexico |
Zhou J.,University of New Mexico |
Zhou J.,Nanjing Normal University |
And 2 more authors.
Chemical Communications | Year: 2013
A FRET ratiometric fluorescent probe enabling a fast and highly sensitive response to OP nerve agent mimic DCP within 1 min and with as low as 0.17 ppm concentration detection limit has been developed. Moreover, the probe exhibits noticeable color changes under UV light and even with the naked eye. It is also demonstrated that it can detect both liquid and gas nerve agents. © 2013 The Royal Society of Chemistry. Source
(E,E)-3,3′-Dimethyl-1,1′-diphenyl-4,4′-{(ethane-1, 2-diyldiimino)-bis-[(2-furyl)methylidyne]}di-1H-pyrazol-5(4H)-one
Wang H.-W.,East China University of Science and Technology
Acta Crystallographica Section E: Structure Reports Online | Year: 2010
The complete molecule of the title compound of the title compound, C 32H28N6O4, is generated by crystallographic inversion symmetry. The dihedral angles between the pyrazalone ring and the pendant phenyl and furan rings are 15.65 (8) and 65.06 (8)°, respectively. In the crystal, the molecules are linked by N-H⋯O, C-H⋯O and weak C-H⋯π interactions. Source
Effect of size and processing method on the cytotoxicity of realgar nanoparticles in cancer cell lines.
Zhao W.,East China University of Science and Technology
International journal of nanomedicine | Year: 2011
In this study, the effects of the size and Chinese traditional processing (including elutriation, water cleaning, acid cleaning, alkali cleaning) on realgar nanoparticles (RN)-induced antitumor activity in human osteosarcoma cell lines (MG-63) and hepatoma carcinoma cell lines (HepG-2) were investigated. The human normal liver cell line (L-02) was used as control. RN was prepared by high-energy ball milling technology. The results showed that with the assistance of sodium dodecyl sulfate, the size of realgar could be reduced to 127 nm after 12 hours' ball milling. The surface charge was decreased from 0.83 eV to -17.85 eV and the content of As2O3 clearly increased. Except for elutriation, the processing methods did not clearly change the size of the RN, but the content of As2O3 was reduced dramatically. In vitro MTT tests indicated that in the two cancer cell lines, RN cytotoxicity was more intense than that of the coarse realgar nanoparticles, and cytotoxicity was typically time- and concentration-dependent. Also, RN cytotoxicities in the HepG-2 and L-02 cells all increased with increasing milling time. Due to the reduction of the As2O3 content, water cleaning, acid cleaning, and alkali cleaning decreased RN cytotoxicity in HepG-2, but RN after elutriation, with the lowest As2O3 (3.5 mg/g) and the smallest size (109.3 nm), showed comparable cytotoxicity in HepG-2 to RN without treatment. Meanwhile, RN-induced cytotoxicity in L-02 cells was clearly reduced. Therefore, it can be concluded that RN may provide a strong antiproliferation effect in the MG-63 and HepG-2 cells. Elutriation processing is a suitable approach to limit the dangerous side-effects of As2O3, while maintaining the effectiveness of RN. Source
In vitro cytotoxicity and induction of apoptosis by silica nanoparticles in human HepG2 hepatoma cells.
Lu X.,East China University of Science and Technology
International journal of nanomedicine | Year: 2011
Silica nanoparticles have been discovered to exert cytotoxicity and induce apoptosis in normal human cells. However, until now, few studies have investigated the cytotoxicity of silica nanoparticles in tumor cells. This study investigated the cytotoxicity of 7-50 nm silica nanoparticles in human HepG2 hepatoma cells, using normal human L-02 hepatocytes as a control. Cell nucleus morphology changes, cellular uptake, and expression of procaspase-9, p53, Bcl-2, and Bax, as well as the activity of caspase-3, and intracellular reactive oxygen species and glutathione levels in the silica nanoparticle-treated cells, were analyzed. The antitumor activity of the silica nanoparticles was closely related to particle size, and the antiproliferation activity decreased in the order of 20 nm > 7 nm > 50 nm. The silica nanoparticles were also cytotoxic in a dose- and time-dependent manner. However, the silica nanoparticles showed only slight toxicity in the L-02 control cells, Moreover, in HepG2 cells, oxidative stress and apoptosis were induced after exposure to 7-20 nm silica nanoparticles. Expression of p53 and caspase-3 increased, and expression of Bcl-2 and procaspase-9 decreased in a dose-dependent manner, whereas the expression of Bax was not significantly changed. A mitochondrial-dependent pathway triggered by oxidative stress mediated by reactive oxygen species may be involved in apoptosis induced by silica nanoparticles, and hence cytotoxicity in human HepG2 hepatic cancer cells. Source
Eshelby's inclusion and dislocation problems for an isotropic circular domain bonded to an anisotropic medium
Wang X.,East China University of Science and Technology
Acta Mechanica | Year: 2015
This paper mainly investigates a two-dimensional Eshelby's problem of an inclusion of arbitrary shape embedded within an isotropic elastic circular domain which is perfectly bonded to the surrounding infinite anisotropic elastic medium. The Muskhelishvili's complex variable formulation in isotropic elasticity and the Stroh formalism in anisotropic elasticity are employed to derive a very simple and explicit analytical solution. The coefficients in the derived six analytic functions within the isotropic circular domain only contain the Barnett-Lothe tensors for the surrounding anisotropic medium and the shear modulus and Poisson's ratio for the isotropic circular domain. Several examples are discussed in detail to demonstrate and validate the obtained analytical solution. By using a similar method, we also investigate a line dislocation located in an isotropic circular cylinder which is perfectly bonded to the surrounding anisotropic medium and derive the image force acting on the line dislocation. © 2014, Springer-Verlag Wien. Source
Xu Z.,CAS Shanghai Institute of Materia Medica |
Yang Z.,CAS Shanghai Institute of Materia Medica |
Liu Y.,CAS Shanghai Institute of Materia Medica |
Lu Y.,East China University of Science and Technology |
And 2 more authors.
Journal of Chemical Information and Modeling | Year: 2014
Halogen bond has attracted a great deal of attention in the past years for hit-to-lead-to-candidate optimization aiming at improving drug-target binding affinity. In general, heavy organohalogens (i.e., organochlorines, organobromines, and organoiodines) are capable of forming halogen bonds while organofluorines are not. In order to explore the possible roles that halogen bonds could play beyond improving binding affinity, we performed a detailed database survey and quantum chemistry calculation with close attention paid to (1) the change of the ratio of heavy organohalogens to organofluorines along the drug discovery and development process and (2) the halogen bonds between organohalogens and nonbiopolymers or nontarget biopolymers. Our database survey revealed that (1) an obviously increasing trend of the ratio of heavy organohalogens to organofluorines was observed along the drug discovery and development process, illustrating that more organofluorines are worn and eliminated than heavy organohalogens during the process, suggesting that heavy halogens with the capability of forming halogen bonds should have priority for lead optimization; and (2) more than 16% of the halogen bonds in PDB are formed between organohalogens and water, and nearly 20% of the halogen bonds are formed with the proteins that are involved in the ADME/T process. Our QM/MM calculations validated the contribution of the halogen bond to the binding between organohalogens and plasma transport proteins. Thus, halogen bonds could play roles not only in improving drug-target binding affinity but also in tuning ADME/T property. Therefore, we suggest that albeit halogenation is a valuable approach for improving ligand bioactivity, more attention should be paid in the future to the application of the halogen bond for ligand ADME/T property optimization. © 2013 American Chemical Society. Source
Liu W.W.,Shanghai JiaoTong University |
Wang J.N.,East China University of Science and Technology |
Wang X.X.,Tongji University
Nanoscale | Year: 2012
Unfunctionalized graphene is positively or negatively charged when it is dispersed in organic solvents. The charging is negative in solvents with high electron donor numbers and positive in those with low donor numbers. We suggest that the charging originates from electron transfer between graphene surfaces and solvent molecules, and the stable dispersion of unfunctionalized graphene in organic solvents is mainly controlled by electrostatic repulsion between the charged graphene surfaces. © 2012 The Royal Society of Chemistry. Source
Jiang Z.T.,East China University of Science and Technology
Zhongguo Zhong xi yi jie he za zhi Zhongguo Zhongxiyi jiehe zazhi = Chinese journal of integrated traditional and Western medicine / Zhongguo Zhong xi yi jie he xue hui, Zhongguo Zhong yi yan jiu yuan zhu ban | Year: 2011
To observe the effects of Tangshen Recipe (TR) on the homocysteine (Hcy) metabolism of patients with diabetic nephropathy. 64 patients with diabetic nephropathy were randomly assigned to two groups, 32 in each. Those in the Western medicine treatment group (Group A) received insulin and orally took anti-diabetic drugs, while those in the TR group (Group B) received insulin and orally took TR (consisting of astragalus, raw rehmannia root, sanchi root, euonymus branchlet, rhubarb, bitter orange, and dogwood fruit, etc. 4 g/package). Six months was taken as one therapeutic course. Another 48 healthy volunteers were recruited as the control group. Eight intermediate metabolites of the homocysteine metabolism in plasma were quantitated before treatment, three months and six months after treatment. The in vivo changes of each metabolite after treatment were analyzed. Compared with the healthy control group, contents of cysteine (Cys), Hcy, s-adenosylmethionine (SAM), and SAH significantly increased in Group A and B before treatment. Contents of methionine (Met), glutathione (GSH), and Cys-gly decreased significantly, showing statistical difference (P<0.05). Patients' in vivo contents of Cys, Hcy, SAM, and SAH significantly decreased, while contents of Met, GSH, and Cys-gly significantly increased after three and six months of treatment when compared with before treatment in the same group (all P<0.05). No statistical difference existed in contents of SAH, SAM, and GSH of Group A and B after six months of treatment when compared with the healthy control group (P>0.05). No adverse reaction occurred in Group A and B. Treatment of insulin and TR showed similar favorable effect to Western medicine in treatment of diabetic nephropathy. It could improve in vivo hypomethylation and oxidative stress. Source
Cheng H.,East China University of Science and Technology
International Journal of Theoretical Physics | Year: 2016
The Casimir effect for parallel plates satisfying the Dirichlet boundary condition in the context of effective QED coming from a six-dimensional Nielsen-Olesen vortex solution of the Abelian Higgs model with fermions coupled to gravity is studied at finite temperature. We find that the sign of the Casimir energy remains negative under the thermal influence. It is also shown that the Casimir force between plates will be weaker in the higher-temperature surroundings while keeps attractive. This Casimir effect involving the thermal influence is still inconsistent with the known experiments. We find that the thermal correction can not compensate or even reduce the modification from this kind of vortex model to make the Casimir force to be in less conflict with the measurements. © 2015, Springer Science+Business Media New York. Source
A highly selective ratiometric near-infrared fluorescent cyanine sensor for cysteine with remarkable shift and its application in bioimaging
Guo Z.,Ewha Womans University |
Guo Z.,East China University of Science and Technology |
Nam S.,Ewha Womans University |
Park S.,Ewha Womans University |
Yoon J.,Ewha Womans University
Chemical Science | Year: 2012
We developed a highly selective ratiometric near-infrared cyanine-based probe CyAC for cysteine (Cys) over homocysteine (Hcy) and glutathione (GSH). Upon the addition of Cys to the solution of CyAC, remarkable shifts in the spectra of CyAC can be monitored (from 770 nm to 515 nm in absorption spectra and from 780 nm to 570 nm in emission spectra). For the first time, the novel strategy that reversibly modulates the polymethine π-electron system by conjugation and removal of the specific trigger moiety was implemented for the generation of a ratiometric cyanine-based sensor. Hydroxy cyanine CyAE was chosen as the flurophore scaffold because the tautomerism (CyAE and CyAK or CyAD) can cause the reversible change in the π-conjugation system of the dyes with large shifts in the spectra. An acrylate group containing a α, β-unsaturated ketone as a functional trigger moiety was incorporated with CyAK to form the sensor CyAC. This specific response for Cys was based on the differences of the kinetics of intramolecular adduct/cyclizations. Moreover, CyAC was successfully applied for bioimaging Cys in living cancer cells. This paradigm by modulation of the polymethine π-electron system in the cyanine dye provides a promising methodology for the design of ratiometric cyanine-based sensors. © 2012 The Royal Society of Chemistry. Source
Xu Y.,East China University of Science and Technology
European Journal of Cancer Prevention | Year: 2015
The Warburg effect, glycolytic production of ATP under aerobic conditions, is found to be a universal feature of most cancer cells. Our study was aimed to determine whether rosmarinic acid (RA) had the anti-Warburg effect activity against colorectal carcinoma. Furthermore, the mechanism for the anti-Warburg effect by RA would be investigated. In our study, we found that RA suppressed glucose consumption and lactate generation in colorectal carcinoma cells; meanwhile, RA inhibited the expression of transcription factor hypoxia-inducible factor-1α (HIF-1α) that affects the glycolytic pathway. Chronic inflammation is a key promoting factor of the Warburg effect. As we supposed, the present study also showed that RA could not only repress proinflammatory cytokines using enzyme-linked immunosorbent assay but it could also suppress microRNAs related to inflammation by real-time PCR. Therefore, we proposed that RA may inhibit the Warburg effect by suppressing the inflammatory response of colorectal carcinoma cells. Recent studies have provided evidence that miR-155 was an important mediator between inflammation and carcinogenesis. We further showed that miR-155 acted to repress the Warburg effect through the mechanism of inactivating the IL-6/STAT3 pathway. Above all, RA might be a potential therapeutic agent against colorectal carcinoma. © 2015 Wolters Kluwer Health, Inc. All rights reserved. Source
Existence results for impulsive neutral stochastic functional integro-differential inclusions with nonlocal initial conditions
Lin A.,East China University of Science and Technology |
Hu L.,Anhui Normal University
Computers and Mathematics with Applications | Year: 2010
In this paper, we prove the existence of mild solutions for a class of impulsive neutral stochastic functional integro-differential inclusions with nonlocal initial conditions and resolvent operators. Sufficient conditions for the existence are derived with the help of the fixed point theorem for multi-valued operators due to Dhage and the fractional power of operators. An example is provided to illustrate the theory. © 2009 Elsevier Ltd. All rights reserved. Source
Xu X.,East China University of Science and Technology
Acta Informatica | Year: 2012
This is a paper on distinguishing and relating two important kinds of calculi through expressiveness, settling some critical but long unanswered questions. The delimitation of higher-order and first-order process calculi is a basic and pivotal topic in the study of process theory. Particularly, expressiveness studies mutual encodability, which helps decide whether process-passing or name-passing is more fundamental, and the way they ought to be used in both theory and practice. In this paper, we contribute to such demarcation with three major results. Firstly π (first-order pi-calculus) can faithfully express Π (basic higher-order pi-calculus). The calculus Π has the elementary operators (input, output, composition and restriction). This actually is a corollary of a more general result, that π can encode Πr (Π enriched with the relabelling operator). Secondly Π cannot interpret Π reasonably. This is of more significance since it separates Π by π drawing a well-defined boundary. Thirdly an encoding from π to Πr is revisited and discussed, which not only implies how to make Π more useful but also stresses the importance of name-passing in Π. © 2012 Springer-Verlag. Source
Wong W.K.,Hong Kong Polytechnic University |
Zhao H.T.,East China University of Science and Technology
Pattern Recognition | Year: 2012
In the past few years, the computer vision and pattern recognition community has witnessed a rapid growth of a new kind of feature extraction method, the manifold learning methods, which attempt to project the original data into a lower dimensional feature space by preserving the local neighborhood structure. Among these methods, locality preserving projection (LPP) is one of the most promising feature extraction techniques. Unlike the unsupervised learning scheme of LPP, this paper follows the supervised learning scheme, i.e. it uses both local information and class information to model the similarity of the data. Based on novel similarity, we propose two feature extraction algorithms, supervised optimal locality preserving projection (SOLPP) and normalized Laplacian-based supervised optimal locality preserving projection (NL-SOLPP). Optimal here means that the extracted features via SOLPP (or NL-SOLPP) are statistically uncorrelated and orthogonal. We compare the proposed SOLPP and NL-SOLPP with LPP, orthogonal locality preserving projection (OLPP) and uncorrelated locality preserving projection (ULPP) on publicly available data sets. Experimental results show that the proposed SOLPP and NL-SOLPP achieve much higher recognition accuracy. © 2011 Elsevier Ltd. All rights reserved. Source
Li C.,Tianjin University of Technology |
Zhang P.,Tianjin University of Technology |
Lv R.,Tianjin University of Technology |
Lu J.,Tianjin University of Technology |
And 4 more authors.
Small | Year: 2013
An efficient homotype Ag3PO4/BiVO4 heterojunction photocatalyst is described. Ag3PO4 nanoparticles preferentially deposit on the highly active BiVO4(040) facets by means of heterojunction construction together with morphology engineering. The Ag3PO4/BiVO4 photocatalyst shows high charge separation efficiency as well as enhanced visible-light response ability and thus possesses superior visible light photocatalytic activity. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Hybrid artificial neural network based on BP-PLSR and its application in development of soft sensors
Xuefeng Y.,East China University of Science and Technology
Chemometrics and Intelligent Laboratory Systems | Year: 2010
A novel hybrid artificial neural network (HANN) integrating error back propagation algorithm (BP) with partial least square regression (PLSR) was proposed to overcome two main flaws of artificial neural network (ANN), i.e. tendency to overfitting and difficulty to determine the optimal number of the hidden nodes. Firstly, single-hidden-layer network consisting of an input layer, a single hidden layer and an output layer is selected by HANN. The number of the hidden-layer neurons is determined according to the number of the modeling samples and the number of the neural network parameters. Secondly, BP is employed to train ANN, and then the hidden layer is applied to carry out the nonlinear transformation for independent variables. Thirdly, the inverse function of the output-layer node activation function is applied to calculate the expectation of the output-layer node input, and PLSR is employed to identify PLS components from the nonlinear transformed variables, remove the correlation among the nonlinear transformed variables and obtain the optimal relationship model of the nonlinear transformed variables with the expectation of the output-layer node input. Thus, the HANN model is developed. Further, HANN was employed to develop naphtha dry point soft sensor and the most important intermediate product concentration (i.e. 4-carboxybenzaldehyde concentration) soft sensor in p-xylene (PX) oxidation reaction due to the fact that there exist many factors having nonlinear effect on them and significant correlation among their factors. The results of two HANN applications show that HANN overcomes overfitting and has the robust character. And, the predicted squared relative errors of two optimal HANN models are all lower than those of two optimal ANN models and the mean predicted squared relative errors of HANN are lower than those of ANN in two applications. © 2010 Elsevier B.V. Source
Sih G.C.,Lehigh University |
Sih G.C.,East China University of Science and Technology
Science China: Physics, Mechanics and Astronomy | Year: 2014
When two contacting solid surfaces are tightly closed and invisible to the naked eye, the discontinuity is said to be microscopic regardless of whether its length is short or long. By this definition, it is not sufficient to distinguish the difference between a micro- and macro-crack by using the length parameter. Microcracks in high strength metal alloys have been known to be several centimeters or longer. Considered in this work is a dual scale fatigue crack growth model where the main crack can be micro or macro but there prevails an inherent microscopic tip region that is damaged depending on the irregularities of the microstructure. This region is referred to as the "micro-tip" and can be simulated by a sharp wedge with different angles in addition to mixed boundary conditions. The combination is sufficient to model microscopic entities in the form of voids, inclusions, precipitations, interfaces, in addition to subgrain imperfections, or cluster of dislocations. This is accomplished by using the method of "singularity representation" such that closed form asymptotic solutions can be obtained for the development of fatigue crack growth rate relations with three parameters. They include: (1) the crack surface tightness σ represented by σ o/σ ∞ = 0.3-0.5 for short cracks in region I, and 0.1-0.2 for long cracks in region II, (2) the micro/macro material properties reflected by the shear modulus ratio μ (=μmicro/ μmacro varying between 2 and 5) and (3) the most sensitive parameter d being the micro-tip characteristic length d (=d/d o) whose magnitude decreases in the direction of region I→II. The existing fatigue crack growth data for 2024-T3 and 7075-T6 aluminum sheets are used to reinterpret the two-parameter da/dN=C(ΔK) n relation where ΔK has now been re-derived for a microcrack with surfaces tightly in contact. The contact force will depend on the mean stress σm or mean stress ratio R as the primary parameter and on the stress amplitude σ a as the secondary parameter. © 2013 Science China Press and Springer-Verlag Berlin Heidelberg. Source
Sih G.C.,Lehigh University |
Sih G.C.,East China University of Science and Technology
Science China: Physics, Mechanics and Astronomy | Year: 2014
The formalism of the earlier fatigue crack growth models is retained to account for multiscaling of the fatigue process that involves the creation of macrocracks from the accumulation of micro damage. The effects of at least two scales, say micro to macro, must be accounted for. The same data can thus be reinterpreted by the invariancy of the transitional stress intensity factors such that the microcracking and macrocracking data would lie on a straight line. The threshold associated with the sigmoid curve disappears. Scale segmentation is shown to be a necessity for addressing multiscale energy dissipative processes such as fatigue and creep. Path independency and energy release rate are monoscale criteria that can lead to unphysical results, violating the first principles. Application of monoscale failure or fracture criteria to nanomaterials is taking toll at the expense of manufacturing super strength and light materials and structural components. This brief view is offered in the spirit of much needed additional research for the reinforcement of materials by creating nanoscale interfaces with sustainable time in service. The step by step consideraton at the different scales may offer a better understanding of the test data and their limitations with reference to space and time. © 2013 Science China Press and Springer-Verlag Berlin Heidelberg. Source
An X.,East China University of Science and Technology |
An X.,Nanjing Normal University |
Zhan F.,Nanjing Normal University |
Zhu Y.,Nanjing Normal University
Langmuir | Year: 2013
Novel thermosensitive liposomes with embedded Au nanoparticles (AuNPs) in the liposome bilayer were prepared by a combination method of film build and supercritical CO2 incubation. These AuNPs-liposomes possess AuNPs that are embedded in the bilayer and a drug that is encapsulated in the central aqueous compartment. The AuNPs in the liposomes can strongly absorb light energy and efficiently convert the absorbed energy to heat. The localized heat induces a phase transition in the liposome bilayer and releases the drug. The drug release from the AuNPs-liposomes can be controlled by the irradiation time and AuNPs concentration in the AuNPs-liposomes at room temperature, where the AuNPs function as a nanoswitch for triggering drug release both spatially and temporally. The results suggest that drug release from the AuNPs-liposomes is due to a photothermic effect that induces phase transition of the liposomes rather than destruction of the liposome bilayer. © 2013 American Chemical Society. Source
Jiang H.,Nanyang Technological University |
Zhao T.,Nanyang Technological University |
Yan C.,Nanyang Technological University |
Ma J.,Nanyang Technological University |
Li C.,East China University of Science and Technology
Nanoscale | Year: 2010
Uniform and single-crystalline Mn3O4 nano-octahedrons have been successfully synthesized by a simple ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) assisted hydrothermal route. The octahedron structures exhibit a high geometric symmetry with smooth surfaces and the mean side length of square base of octahedrons is ∼160 nm. The structure is reckoned to provide superior functional properties and the nano-size achieved in the present work is noted to further facilitate the material property enhancement. The formation process was proposed to begin with a "dissolution- recrystallization" which is followed by an "Ostwald ripening" mechanism. The Mn3O4 nano-octahedrons exhibited an enhanced specific capacitance of 322 F g-1 compared with the truncated octahedrons with specific capacitances of 244 F g-1, making them a promising electrode material for supercapacitors. © The Royal Society of Chemistry 2010. Source
Yeast surface display of trifunctional minicellulosomes for simultaneous Saccharification and fermentation of cellulose to ethanol
Wen F.,University of Illinois at Urbana - Champaign |
Sun J.,University of Illinois at Urbana - Champaign |
Sun J.,East China University of Science and Technology |
Zhao H.,University of Illinois at Urbana - Champaign
Applied and Environmental Microbiology | Year: 2010
By combining cellulase production, cellulose hydrolysis, and sugar fermentation into a single step, consolidated bioprocessing (CBP) represents a promising technology for biofuel production. Here we report engineering of Saccharomyces cerevisiae strains displaying a series of uni-, bi-, and trifunctional minicellulosomes. These minicellulosomes consist of (i) a miniscaffoldin containing a cellulose-binding domain and three cohesin modules, which was tethered to the cell surface through the yeast a-agglutinin adhesion receptor, and (ii) up to three types of cellulases, an endoglucanase, a cellobiohydrolase, and a β-glucosidase, each bearing a C-terminal dockerin. Cell surface assembly of the minicellulosomes was dependent on expression of the miniscaffoldin, indicating that formation of the complex was dictated by the high-affinity interactions between cohesins and dockerins. Compared to the unifunctional and bifunctional minicellulosomes, the quaternary trifunctional complexes showed enhanced enzyme-enzyme synergy and enzyme proximity synergy. More importantly, surface display of the trifunctional minicellulosomes gave yeast cells the ability to simultaneously break down and ferment phosphoric acid-swollen cellulose to ethanol with a titer of ∼1.8 g/liter. To our knowledge, this is the first report of a recombinant yeast strain capable of producing cell-associated trifunctional minicellulosomes. The strain reported here represents a useful engineering platform for developing CBP-enabling microorganisms and elucidating principles of cellulosome construction and mode of action. © 2010, American Society for Microbiology. All Rights Reserved. Source
Nuli Y.,Shanghai JiaoTong University |
Yang J.,Shanghai JiaoTong University |
Li Y.,East China University of Science and Technology |
Wang J.,Shanghai JiaoTong University
Chemical Communications | Year: 2010
Mesoporous magnesium manganese silicate materials were prepared using mesoporous silica SBA-15 or KIT-6 as both template and silicon source. The materials exhibited improved electrochemical intercalation and deintercalation toward Mg2+, compared with the corresponding bulk material. © 2010 The Royal Society of Chemistry. Source
Xu S.,Swinburne University of Technology |
Xu S.,East China University of Science and Technology |
Beynon J.H.,Swinburne University of Technology |
Ruan D.,Swinburne University of Technology |
Lu G.,Nanyang Technological University
Composite Structures | Year: 2012
The out-of-plane crushing behaviour of four types of aluminium hexagonal honeycombs was extensively investigated over a wide range of strain rates where each test was conducted at a constant compressive velocity. The effects of specimen dimensions, relative density, strain rate and honeycomb cell size on the mechanical properties of honeycombs were studied. It was demonstrated that the mean plateau force was linearly related to the specimen dimensions. However, the calculated plateau stress varied with specimen dimensions and a minimum of 9 × 9. cells should be used in order to represent the bulk properties of honeycombs. A large strength enhancement of honeycombs was observed when the relative density and strain rate increased. The tangent modulus also increased towards the end of the crushing process, especially for those honeycombs with small values of wall thickness to edge length ratio (t/l). Semi-empirical relations were obtained to describe the effects of relative density (t/l ratio) and strain rate on the plateau stress. The difference in deformation patterns for honeycombs between quasi-static and dynamic loading conditions was also discussed. © 2012 Elsevier Ltd. Source
A numerical framework for two-dimensional large deformation of inhomogeneous swelling of gels using the improved complex variable element-free Galerkin method
Li D.M.,City University of Hong Kong |
Zhang Z.,East China University of Science and Technology |
Liew K.M.,City University of Hong Kong
Computer Methods in Applied Mechanics and Engineering | Year: 2014
A numerical framework based on the improved complex variable element-free Galerkin (ICVEFG) method is developed for large deformation analysis of inhomogeneous swelling of gels. In this work, a decomposed free-energy function is derived that avoids the difficulty of treating the chemical potential as a temperature-like variable by changing the chemical potential load into a mechanical load. The Galerkin weak form equation system is derived for inhomogeneous swelling of gels. The essential boundary conditions are imposed through the penalty method. This leads to the corresponding formulae of the improved complex variable moving least-squares (ICVMLS) approximation for 2-D large deformation inhomogeneous swelling of gels. Some example problems of inhomogeneous swelling induced behaviors such as wrinkling, crease and bifurcation are investigated using the developed ICVEFG framework. © 2014 Elsevier B.V. Source
Yao Z.T.,Hangzhou Dianzi University |
Ji X.S.,Zhejiang University |
Sarker P.K.,Curtin University Australia |
Tang J.H.,Hangzhou Dianzi University |
And 4 more authors.
Earth-Science Reviews | Year: 2015
Coal fly ash, an industrial by-product, is derived from coal combustion in thermal power plants. It is one of the most complex anthropogenic materials, and its improper disposal has become an environmental concern and resulted in a waste of recoverable resources. There is a pressing and ongoing need to develop new recycling methods for coal fly ash. The present review first describes the generation, physicochemical properties and hazards of coal fly ash at the global level, and then focuses on its current and potential applications, including use in the soil amelioration, construction industry, ceramic industry, catalysis, depth separation, zeolite synthesis, etc. Finally, the advantages and disadvantages of these applications, the mode of fly ash utilization worldwide and directions for future research are considered. © 2014 Elsevier B.V. Source
Fang W.Q.,Key Laboratory for Ultrafine Materials |
Gong X.-Q.,East China University of Science and Technology |
Yang H.G.,Key Laboratory for Ultrafine Materials
Journal of Physical Chemistry Letters | Year: 2011
As an important metal oxide, anatase titanium dioxide has been widely investigated because of its many promising properties. The properties of anatase TiO 2 crystals are largely determined by exposed external surfaces. Since the breakthrough in synthesizing anatase TiO 2 single crystals with a large percentage of highly reactive {001} facets in 2008, many unusual properties and applications of these {001} facets dominant in anatase TiO 2 have been explored theoretically and experimentally, showing the industrial importance of this semiconductor material. This Perspective focuses on the theoretical simulations and application explorations of the unusual properties of anatase TiO 2 bound by highly reactive facets. Research opportunities as well as the challenges for future research in this emerging frontier are also highlighted. © 2011 American Chemical Society. Source
Liang K.,University of Hong Kong |
Liang K.,East China University of Science and Technology
Aging and Mental Health | Year: 2014
Objectives: This study examined subjective age and its cross-domain correlates in Chinese oldest-old.Method: We conducted a secondary data analysis using cross-sectional data drawn from the 2006 Sample Survey on the Aged Population in Urban/Rural China, which consisted of a sample of 860 community-dwelling Chinese older adults aged 85 years and above.Results: A small percentage (8%) of the oldest-old participants reported that they did not feel old. Binary logistic regression analyses revealed that urban living, better physical and self-reported cognitive functioning and mental health were all related to not feeling old, whereas chronological age was found to have no association with subjective age when controlling for indicators of physical and self-reported cognitive functioning.Conclusion: The findings revealed the key roles of functional limitations and mental health in the construction of subjective age in Chinese oldest-old. The possible cross-cultural similarity in the links of subjective age to mental health and physical functioning in later life suggests that maintaining a youthful subjective age may have adaptive value for the oldest-old and contribute to their successful aging. © 2013 Taylor & Francis. Source
Wang H.,University of Hong Kong |
Leung D.Y.C.,University of Hong Kong |
Xuan J.,University of Hong Kong |
Xuan J.,East China University of Science and Technology
Applied Energy | Year: 2013
A numerical model for a microfluidic electrolytic cell (MEC) for CO2 utilization and fuel production is developed and validated against experimental data in literature. Mass transfer and electrochemical characteristics at the cathode of the MEC are studied. Limiting factors to the cell performance are found to be (i) low diffusivity of CO2 in the porous electrode, (ii) competing hydrogen evolution reaction (HER) at the cathode and (iii) dilution effect of hydrogen. Parametric effects are also studied to find strategies to optimize the cell performance. © 2012 Elsevier Ltd. Source
Design and screening of a chimeric survivin-specific nanobody and its anticancer activities in vitro
Zhang N.,East China University of Science and Technology
Anti-Cancer Drugs | Year: 2016
Survivin is a strong inhibitor of apoptosis protein and a promising target for cancer prevention and treatment. Here, we report the design and preparation of novel chimeric nanobodies (Nbs) that could specifically bind to survivin. We screened the peptides from phage-displayed libraries (7-mer, 12-mer) for nonconserved sequences of complementarity-determining regions (CDRs) in the scaffold of the Nb. By a combination of the nonconserved sequences for CDRs, the corresponding chimeric Nbs (10 Nbs) were prepared with genetic operations. The antisurvivin Nb TAT-Nb4A (a fusion with cellular transduction peptide TAT) was found to be the most efficient antibody on the basis of the results from enzyme-linked immunosorbent assay, MTT, and flow cytometry when these nanobodies were tested with hepatoma carcinoma cell HepG2. TAT-Nb4A could inhibit the growth of HepG2 and promote cancer cell apoptosis significantly in a dose-dependent and time-dependent manner: the apoptosis rate reached 52.5% when the concentration of TAT-Nb4A was 120 μg/ml. Western blotting with cells expressing survivin showed that the prepared nanobody could efficiently bind to expressed survivin and blocked the signaling pathway in which survivin played a role. This study provided a convenient and feasible method of obtaining a novel specific Nb with the case of survivin as a good example. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved. Source
Programmable self-assembly of homo- or hetero-metallomacrocycles using 4-(1H-pyrazolyl-4-yl)pyridine
Tong J.,Renmin University of China |
Yu S.-Y.,Renmin University of China |
Li H.,East China University of Science and Technology
Chemical Communications | Year: 2012
The dimetallic [M 2(bpy) 2(NO 3) 2](NO 3) 2 moieties (M = Pd(ii) or Pt(ii)) react preferentially at the pyrazolyl end of the pyridyl-pyrazole ligand, giving rise to dimetallic corners. Subsequently, the dimetallic corner building blocks featuring two pyridine donors are coordinated by monometallic [M(bpy)(NO 3) 2] moieties (M = Pd(ii) or Pt(ii)) to form homo- or hetero-metallomacrocycles. © 2012 The Royal Society of Chemistry. Source
Deng S.,East China University of Science and Technology
Advances in Applied Mathematics and Mechanics | Year: 2016
Bell Polynomials play an important role in the characterization of bilinear equation. Bell Polynomials are extended to construct the bilinear form, bilinear Bäcklund transformation and Lax pairs for the Kadomtsev-Petviashvili equation with self-consistent sources. © 2016 Global Science Press. Source
Xie H.,East China University of Science and Technology
AIAA Journal | Year: 2013
A new iterative method is proposed to compute many eigenpair derivatives of damped systems with respect to system parameters. The state-space form of damped system is not used. The proposed method simultaneously computes the derivatives of many eigenpairs, and the solution of many large linear systems of equations with different coefficient matrices is avoided. Numerical experiments demonstrate that the proposed method can be efficiently used for the computation of the derivatives of the r eigenpairs with largest magnitude in large symmetric damped systems. Moreover, when the size n of system and the number r of desired eigenpair derivatives become larger, the proposed method has more advantage. Copyright © 2012 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved. Source
He W.,East China University of Science and Technology |
Cao J.,Nanjing Southeast University
IEEE Transactions on Neural Networks | Year: 2010
This paper investigates exponential synchronization of coupled networks with hybrid coupling, which is composed of constant coupling and discrete-delay coupling. There is only one transmittal delay in the delayed coupling. The fact is that in the signal transmission process, the time delay affects only the variable that is being transmitted from one system to another, then it makes sense to assume that there is only one single delay contributing to the dynamics. Some sufficient conditions for synchronization are derived based on Lyapunov functional and linear matrix inequality (LMI). In particular, the coupling matrix may be asymmetric or nondiagonal. Moreover, the transmittal delay can be different from the one in the isolated system. A distinctive feature of this work is that the synchronized state will vary in comparison with the conventional synchronized solution. Especially, the degree of the nodes and the inner delayed coupling matrix heavily influence the synchronized state. Finally, a chaotic neural network is used as the node in two regular networks to show the effectiveness of the proposed criteria. © 2006 IEEE. Source
Feng M.,Fuzhou University |
Zhan H.,Fuzhou University |
Chen Y.,East China University of Science and Technology
Applied Physics Letters | Year: 2010
The nonlinear optical (NLO) and optical limiting (OL) properties of graphene families, including graphene oxide nanosheets, graphene nanosheets (GNSs), graphene oxide nanoribbons (GONRs), and graphene nanoribbons (GNRs), were investigated at 532 and 1064 nm using a nanosecond regime. GNSs, GONRs, and GNRs exhibited broadband NLO and OL properties. Reduced graphene samples exhibited stronger NLO and OL responses than their graphene oxide precursors because of their increased crystallinity and conjugation. Nonlinear scattering and two-photon-absorption were found to have strong effects on the NLO and OL responses of the graphene nanostructures. © 2010 American Institute of Physics. Source
Zhang L.,East China University of Science and Technology |
Dupuis R.,Upper Alsace University
JVC/Journal of Vibration and Control | Year: 2011
Experimental techniques and identification of dynamic properties of flexible polyurethane foam used in automotive seats are described here. In the experimental fixture a rigid block is mounted on a 3 inch cube of foam material, which serves as the only flexible component. The dynamic system is modeled as a single degree-of -freedom system. The experimental fixture is excited by a small impulse at the top of the block and by a shaker on the basement. For the first situation the foam is simplified as a linear viscoelastic material. By exciting with the shaker the nonlinear and viscoelastic properties of foam materials are considered. For these two different cases not only the model response and the impact of model parameters are analyzed but also the corresponding system parameters are identified during the experimental data. © 2010 The Author(s). Source
Facile ultrasonic synthesis of coo quantum dot/graphene nanosheet composites with high lithium storage capacity
Peng C.,Tongji University |
Chen B.,Tongji University |
Qin Y.,Tongji University |
Yang S.,Clear Technology |
And 4 more authors.
ACS Nano | Year: 2012
In this paper, we report a facile ultrasonic method to synthesize well-dispersed CoO quantum dots (3-8 nm) on graphene nanosheets at room temperature by employing Co 4(CO) 12 as cobalt precursor. The prepared CoO/graphene composites displayed high performance as an anode material for lithium-ion battery, such as high reversible lithium storage capacity (1592 mAh g -1 after 50 cycles), high Coulombic efficiency (over 95%), excellent cycling stability, and high rate capability (1008 mAh g -1 with a total retention of 77.6% after 50 cycles at a current density of 1000 mA g -1, dramatically increased from the initial 50 mA g -1). The extraordinary performance arises from the structure advantages of the composites: the nanosized CoO quantum dots with high dispersity on conductive graphene substrates supply not only large quantity of accessible active sites for lithium-ion insertion but also good conductivity and short diffusion length for lithium ions, which are beneficial for high capacity and rate capability. Meanwhile, the isolated CoO quantum dots anchored tightly on the graphene nanosheets can effectively circumvent the volume expansion/contraction associated with lithium insertion/extraction during discharge/charge processes, which is good for high capacity as well as cycling stability. Moreover, regarding the anomalous behavior of capacity increase with cycles (activation effect) observed, we proposed a tentative hypothesis stressing the competition between the conductivity increase and the amorphorization of the composite electrodes during cycling in determining the trends of the capacity, in the hope to gain a fuller understanding of the inner working of the novel nanostructured electrode-based lithium-ion batteries. © 2012 American Chemical Society. Source
Guo Z.,Ewha Womans University |
Guo Z.,East China University of Science and Technology |
Shin I.,Yonsei University |
Yoon J.,Ewha Womans University
Chemical Communications | Year: 2012
A boronic acid moiety can bind to nucleophilic species, such as fluoride ions and 1,2-diols, and arylboronates are converted to the corresponding phenols by treatment with hydrogen peroxide. Based on these reactivity profiles of boron compounds, a variety of boronic acid and boronate-based fluorescent chemosensors have been developed for detecting biologically relevant species. This feature article highlights recent advances that have been made in the development of chemosensors of these types for monitoring carbohydrates, dopamine, fluorides, metal ions and hydrogen peroxide. © 2012 The Royal Society of Chemistry. Source
Xuan W.,University of New Mexico |
Sheng C.,Shanghai University |
Cao Y.,University of New Mexico |
He W.,University of New Mexico |
And 2 more authors.
Angewandte Chemie - International Edition | Year: 2012
Detective work: Three highly sensitive and selective fluorescent probes for the detection of H 2S have been developed. Two of the probes detect H 2S by the reduction of an azide moiety to an amine group, which changes the probes into their fluorescent forms and generates a fluorescent signal. In the third method, the fluorescent signal is created by using H 2S as a nucleophile in a reaction that unmasks fluorescein. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Liu M.,City University of Hong Kong |
Liu M.,Harbin Institute of Technology |
Ho D.W.C.,City University of Hong Kong |
Niu Y.,East China University of Science and Technology
IEEE Transactions on Signal Processing | Year: 2010
This work is to investigate the problem of filter design for uncertain stochastic systems with mode-dependent quantized output measurements. The issues involved in this correspondence are output logarithmic quantization, Markovian jump parameters, It stochastic noise, and state noise. By employing an effective mathematical transformation, the quantization error of the output in the system equation is converted into a bounded nonlinearity. Based on the proposed model, a mode-dependent H∞ filter is designed, and sufficient conditions are established such that the filtering error system is robustly stochastically stable. A simulation example is presented to illustrate the effectiveness of the proposed approach. © 2010 IEEE. Source
Shi J.,CAS Shanghai Institute of Ceramics |
Shi J.,East China University of Science and Technology |
Shi J.,CAS Institute of Process Engineering
Chemical Reviews | Year: 2013
The heterogeneous catalytic performance is largely dependent on the catalyst nanostructures or, in another word, processing technologies, in addition to the intrinsic physical and chemical properties of the constitutive components. Compared to the amorphous framework of mesoporous silica, mesoporous metal oxides synthesized by a hard templatereplicating method usually have a crystallized structure and exhibit excellent catalytic activities, as reported in many documents. The loading or dispersion of catalytically active guest species into the host mesopore network results in mesostructured composites of a crystallized framework and highly dispersed catalytic species in its mesopore network. Mesoporous inorganic oxide materials, in the form of either powder or thin film, with high surface areas, ordered pore structures, finely tunable pore sizes, and flexible wallcompositions have been investigated widely of their chemical synthesis and potential applications in catalysis, adsorption, chemical sensing, electrochemistry, biomedical areas, and so on. Source
Analysis of second-harmonic generation by primary ultrasonic guided wave propagation in a piezoelectric plate
Deng M.,Chongqing University |
Xiang Y.,East China University of Science and Technology
Ultrasonics | Year: 2015
Abstract The effect of second-harmonic generation (SHG) by primary ultrasonic guided wave propagation is analyzed, where the nonlinear elastic, piezoelectric, and dielectric properties of the piezoelectric plate material are considered simultaneously. The formal solution of the corresponding second-harmonic displacement field is presented. Theoretical and numerical investigations clearly show that the SHG effect of primary guided wave propagation is highly sensitive to the electrical boundary conditions of the piezoelectric plate. The results obtained may provide a means through which the SHG efficiency of ultrasonic guided wave propagation can effectively be regulated by changing the electrical boundary conditions of the piezoelectric plate. © 2015 Elsevier B.V. Source
A study on the magnetic and photoluminescence properties of Eu(n+) and Sm3+ doped Fe3O4 nanoparticles.
Huan W.,East China University of Science and Technology
Journal of nanoscience and nanotechnology | Year: 2012
In this paper, Eu(n+), Sm3+ doped Fe3O4 nanoparticles were prepared via solvothermal method, in which Ferric chloride is used as the iron source, and anhydrous EuCl3, SmCl3 as doping source. Eu, Sm valence in doped Fe3O4 nanoparticles, and effects of Eu, Sm doping amount on their structure, morphology, magnetic properties and PL properties were discussed. The results show, the Eu ions had doped Fe3O4 nanoparticles in the mixed-valence state, when the Eu and Sm doping amount were increased, the doped Fe3O4 nanoparticles changed from hollow nanospheres into spherical particles, and finally changed into uniform cube-shaped particles with 13 nm in diameter. Moreover, the doping sites for doping ions in doped Fe3O4 nanoparticles were discussed from Rietveld analysis of XRD pattern of the doped Fe3O4 nanoparticles. And the changes of the magnetic and PL properties with the doping amount were further discussed. It was found that higher Sm(3+)-doping amount led to stronger magnetic dipole transitions, while the Eu(n+)-doping amount had little effect on the magnetic dipole transitions, thus resulting in different changes in their saturation magnetization with doping amount. Source
Wang X.,East China University of Science and Technology
Communications in Computer and Information Science | Year: 2013
A three dimensional vision sensing system was used to mimic the human vision system to observe the three-dimensional weld pool surface in pipe Gas Tungsten Arc Welding (GTAW) process. Novel characteristic parameters containing information about the penetration state specified by its back-side weld pool width and height were proposed based on the reconstructed three dimensional weld pool surfaces. In order to obtain the penetration status in real time conveniently, a neural network model was established to estimate the penetration based on the proposed characteristic parameters. It was found that the top-side characteristic parameters proposed can reflect the back-side weld pool parameters accurately and the neural network is capable of predicting the penetration status in real time by observing the three-dimensional weld pool surface which is beneficial for penetration control of GTAW process. © Springer-Verlag Berlin Heidelberg 2013. Source
Architecture, self-assembly and properties of well-defined hybrid polymers based on polyhedral oligomeric silsequioxane (POSS)
Zhang W.,East China University of Science and Technology |
Muller A.H.E.,Johannes Gutenberg University Mainz
Progress in Polymer Science | Year: 2013
Well-defined hybrid polymers based on polyhedral oligomeric silsequioxane (POSS) with a variety of architectures have been developed, including telechelic polymers, block copolymers and star-shaped polymers. The synthesis, self-assembly and properties of this kind of materials are reviewed. Well-defined POSS-containing hybrid polymers can be constructed by living polymerization techniques, such as ring-opening polymerization and living free-radical polymerization or the combination of living polymerization and coupling reactions, such as click chemistry and hydrosilylation. The self-assembly behavior of well-defined POSS-containing hybrid polymers is also described in detail. The POSS-containing hybrid polymers can self-assemble into nano-scaled aggregates in selective solvents, and form nanostructures in bulk. Some of the interesting self-assembly morphologies are remarkably different from those formed from the conventional purely organic amphiphilic polymers. Well-defined POSS-containing hybrid polymers have shown the unexpected properties, which lead to unlimited possibilities for promising applications, such as biomedicine, electronic, optical, magnetic nanodevices, sensors and stimulated catalysts. We highlight several recent examples of these applications. © 2013 Elsevier Ltd. Source
Liu Y.,University of Illinois at Urbana - Champaign |
Chen X.,East China University of Science and Technology |
Noh K.W.,University of Illinois at Urbana - Champaign |
Dillon S.J.,University of Illinois at Urbana - Champaign
Nanotechnology | Year: 2012
This work demonstrates electron beam induced deposition of silicon from a SiCl 4 liquid precursor in a transmission electron microscope and a scanning electron microscope. Silicon nanodots of tunable size are reproducibly grown in controlled geometries. The volume of these features increases linearly with deposition time. The results indicate that secondary electrons generated at the substrate surface serve as the primary source of silicon reduction. However, at high current densities the influence of the primary electrons is observed to retard growth. The results demonstrate a new approach to fabricating silicon nanostructures and provide fundamental insights into the mechanism for liquid phase electron beam induced deposition. © 2012 IOP Publishing Ltd. Source
Sun Y.,Wuhan University |
Lim K.H.,City University of Hong Kong |
Peng J.Z.,East China University of Science and Technology
Journal of the Association of Information Systems | Year: 2013
Online designers have widely adopted banners as a popular online advertising format. However, because of their low click-through rates, marketers have recently questioned the effectiveness of banners. A phenomenon called "banner blindness" suggests that salient stimuli, such as banners, are often missed by Internet users. This contradicts the distinctiveness view, which argues that salient stimuli are more likely to attract a user's attention and enhance the click-through rate. To solve this debate, we develop a research framework to explain from an evolutionary perspective how the banner processing mode evolves. More specifically, we develop a process model that shows the transitions between three banner processing modes - automatic salience capture, controlled salience suppression, and automatic salience suppression. In addition, a unified variance model is proposed to solve the distinctiveness - blindness debate. Specifically, we propose that the habituation level and the task type can moderate the effects of structural factors and semantic factors on attention. We also discuss empirical strategies for examining the model and future research. Source
Wonga W.K.,Hong Kong Polytechnic University |
Zhao H.,East China University of Science and Technology
Information Fusion | Year: 2013
Recently, a number of studies have demonstrated that thermal infrared (IR) imagery offers a promising alternative to visible imagery in face recognition problems due to its invariance to visible illumination changes. However, thermal IR has other limitations such as being opaque to glass. As a result, thermal IR imagery is very sensitive to facial occlusion caused by eyeglasses. Fusion of the visible and thermal IR images is an effective way to solve this problem. In this paper, using the face reconstruction information of the visible images, we propose two thermal image reconstruction algorithms, called the visible information aided eyeglasses removing algorithm (VIAER) and the refined visible information aided eyeglasses removing algorithm (refined VIAER). Experiments on publicly available data set show the excellent performance of our algorithms. © 2012 Elsevier B.V. All rights reserved. Source
Seasonal dynamics of ammonia/ammonium-oxidizing prokaryotes in oxic and anoxic wetland sediments of subtropical coastal mangrove
Wang Y.-F.,University of Hong Kong |
Feng Y.-Y.,East China University of Science and Technology |
Ma X.,Lanzhou University |
Gu J.-D.,University of Hong Kong
Applied Microbiology and Biotechnology | Year: 2013
Mangrove wetlands are an important ecosystem in tropical and subtropical regions, and the sediments may contain both oxic and anoxic zones. In this study, ammonia/ ammonium-oxidizing prokaryotes (AOPs) in yellow and black sediments with vegetation and non-vegetated sediments in a mangrove wetland of subtropical Hong Kong were investigated in winter and summer. The phylogenetic diversity of anammox bacterial 16S rRNA genes and archaeal and bacterial amoA genes (encoding ammonia monooxygenase alpha-subunit) were analyzed using PCR amplification and denaturing gradient gel electrophoresis to reveal their community structures. Quantitative PCR was also used to detect their gene abundances. The results showed that seasonality had little effect, but sediment type had a noticeable influence on the community structures and abundances of anammox bacteria. For ammoniaoxidizing archaea (AOA), seasonality had a small effect on their community structures, but a significant effect on their abundances: AOA amoA genes were significantly higher in winter than in summer. In winter, the vegetated yellow sediments had lower AOA amoA genes than the other types of sediments, but in summer, the vegetated yellow sediments had higher AOA amoA genes than the other types of sediments. Sediment type had no apparent effect on AOA community structures in winter. In summer, however, the vegetated yellow sediments showed obviously different AOA community structures from the other types of sediments. For ammonia-oxidizing bacteria (AOB), seasonality had a significant effect on their community structures and abundances: AOB amoA genes in winter were apparently higher than in summer, and AOB community structures were different between winter and summer. Sediment type had little effect on AOB community structures, but had a noticeable effect on the abundances: AOB amoA genes of the vegetated yellow sediments were obviously lower than the black ones in both seasons. This study has demonstrated that seasonality and sediment type affected community structures and abundances of AOPs differently in oxic and anoxic sediments of the mangrove wetland. © The Author(s) 2012. This article is published with open access at Springerlink.com. Source
Zhang W.,University of Kentucky |
Wang X.,East China University of Science and Technology |
Zhang Y.,University of Kentucky
Measurement Science and Technology | Year: 2013
The ability to observe and measure weld pool surfaces in real-time is the core of the foundation for next generation intelligent welding that can partially imitate skilled welders who observe the weld pool to acquire information on the welding process. This study aims at the real-time measurement of the specular three-dimensional (3D) weld pool surface under a strong arc in gas tungsten arc welding (GTAW). An innovative vision system is utilized in this study to project a dot-matrix laser pattern on the specular weld pool surface. Its reflection from the surface is intercepted at a distance from the arc by a diffuse plane. The intercepted laser dots illuminate this plane producing an image showing the reflection pattern. The deformation of this reflection pattern from the projected pattern (e.g. the dot matrix) is used to derive the 3D shape of the reflection surface, i.e., the weld pool surface. Based on careful analysis, the underlying reconstruction problem is formulated mathematically. An analytic solution is proposed to solve this formulated problem resulting in the weld pool surface being reconstructed on average in 3.04 ms during welding experiments. A vision-based monitoring system is thus established to measure the weld pool surface in GTAW in real-time. In order to verify the effectiveness of the proposed reconstruction algorithm, first numerical simulation is conducted. The proposed algorithm is then tested on a spherical convex mirror with a priori knowledge of its geometry. The detailed analysis of the measurement error validates the accuracy of the proposed algorithm. Results from the real-time experiments verify the robustness of the proposed reconstruction algorithm. © 2013 IOP Publishing Ltd. Source
He X.,East China University of Science and Technology |
Wong D.F.K.,City University of Hong Kong
International Journal of Social Psychiatry | Year: 2013
Background: There are approximately 47.5 million female migrant workers living in major cities in China. Numerous studies have documented the marginalized living conditions confronting migrant workers in cities, such as employment difficulties, unjustifiably demanding working conditions, lack of medical insurance and social provision, poor housing conditions, unfavourable educational arrangements for migrant children, and discrimination by urban residents. In addition, female migrant workers may suffer from discrimination, exploitation and oppression. Aim: This study aimed to explore the difficulties and perceived meaningfulness of migration and their effect on the mental health status of female migrant workers in Shanghai, Kunshan, Dongguan and Shenzhen. Methods: A total of 959 female migrant workers from 12 factories completed the questionnaires, which included the Brief Symptom Inventory, the Migration Stress Scale and the Meaning in Migration Scale. Results: The findings indicate that 24% of female migrant workers could be classified as having poor mental health and the percentage in Shenzhen (35%) was far greater than in the three other cities in China. Financial and employment-related difficulties, cultural differences, gender-specific stressors and better future for self and children significantly accounted for the mental health outcomes of female migrant workers. Conclusion: Recommendations for policy change and service initiatives targeted at improving the mental health of female migrant workers are discussed. © 2011 The Author(s). Source
Lou J.,City University of Hong Kong |
Fang Y.,City University of Hong Kong |
Lim K.H.,City University of Hong Kong |
Peng J.Z.,East China University of Science and Technology
Journal of the American Society for Information Science and Technology | Year: 2013
This study investigates the motivational factors affecting the quantity and quality of voluntary knowledge contribution in online Q&;A communities. Although previous studies focus on knowledge contribution quantity, this study regards quantity and quality as two important, yet distinct, aspects of knowledge contribution. Drawing on self-determination theory, this study proposes that five motivational factors, categorized along the extrinsic-intrinsic spectrum of motivation, have differential effects on knowledge contribution quantity versus quality in the context of online Q&;A communities. An online survey with 367 participants was conducted in a leading online Q&;A community to test the research model. Results show that rewards in the reputation system, learning, knowledge self-efficacy, and enjoy helping stand out as important motivations. Furthermore, rewards in the reputation system, as a manifestation of the external regulation, is more effective in facilitating the knowledge contribution quantity than quality. Knowledge self-efficacy, as a manifestation of intrinsic motivation, is more strongly related to knowledge contribution quality, whereas the other intrinsic motivation, enjoy helping, is more strongly associated with knowledge contribution quantity. Both theoretical and practical implications are discussed. © 2012 ASIS&;T. Source
Liu W.W.,Shanghai JiaoTong University |
Wang J.N.,East China University of Science and Technology
Chemical Communications | Year: 2011
We report a facile method for the production of graphene sheets through the liquid-phase exfoliation of graphite in organic solvents with addition of NaOH. NaOH was found to be intercalated into the interplanar spaces of graphite, and greatly improves exfoliation efficiency up to 20 times. © 2011 The Royal Society of Chemistry. Source
[Cloning, expression and immunodiagnostic analysis of Schistosoma japonicum calcium-binding EF-hand domain containing protein].
Lu Y.,East China University of Science and Technology
Zhongguo ji sheng chong xue yu ji sheng chong bing za zhi = Chinese journal of parasitology & parasitic diseases | Year: 2012
To clone and expression Schistosoma japonicum calcium-binding EF-hand domain containing protein (SjEFCAB), purify the expressed protein, and evaluate its antigenicity and diagnostic value. The positive clone screened from egg cDNA library was used as template to amplify the SjEFCAB gene by PCR. The target fragment was cloned into prokaryotic expression vector pGEX-4T-1. The positive recombinant plasmids were transformed into E.coli BL21 and induced by IPTG for expression of the protein. The recombinant protein was purified with GST-tag affinity chromatography. Western blotting was used to analyze the antigenicity. The purified protein was used as coating antigen for indirect ELISA to evaluate its diagnostic effect. Serum samples from patients with schistosomiasis japonica (78 cases), clonorchiasis sinensis (5 cases), cysticercosis (10 cases), paragonimiasis westermani (6 cases), trichinosis (9 cases) and healthy persons (50 cases) were examined. The recombinant plasmid pGEX-4T-1-SjEFCAB was constructed and the SjEFCAB recombinant protein (Mr 8 200) was expressed in E. coli. The soluble fusion protein was purified with affinity chromatography. Western blotting analysis showed that the recombinant protein was recognized by sera of infected rabbits and pooled sera of schistosomiasis japonica patients. The sensitivity and specificity of ELISA for diagnosis of schistosomiasis japonica were 82.1% (64/78) and 95.0% (76/80), respectively. The cross reaction with sera of clonorchiasis sinensis, cysticercosis, and trichinosis patients were 1/5, 1/10, and 1/9, respectively. There was no cross reaction with sera of paragonimiasis westermani patients. The recombinant SjEFCAB antigen has potential diagnostic value for schistosomiasis japonica. Source
Development of 3-dimensional time-dependent density functional theory and its application to gas diffusion in nanoporous materials
Liu Y.,East China University of Science and Technology
Physical Chemistry Chemical Physics | Year: 2016
I developed a novel time-dependent density functional theory (TDDFT) and applied it to complicated 3-dimensional systems for the first time. Superior to conventional TDDFT, the diffusion coefficient is modeled as a function of density profile, which is self-determined by the entropy scaling rule instead using an input parameter. The theory was employed to mimic gas diffusion in a nanoporous material. The TDDFT prediction on the transport diffusivity was reasonable compared to simulations. Moreover, the time-dependent density profiles gave an insight into the microscopic mechanism of the diffusion process. © the Owner Societies 2016. Source
Wang X.,East China University of Science and Technology
Mathematics and Mechanics of Solids | Year: 2012
The problem of two non-elliptical inclusions with internal uniform fields embedded in an infinite matrix, subjected at infinity to a uniform stress field, is discussed in detail by means of the conformal mapping technique. The introduced conformal mapping function can map the matrix region (excluding the two inclusions) onto an annulus. The problem is completely solved for anti-plane isotropic elasticity, anti-plane piezoelectricity, anti-plane anisotropic elasticity, plane elasticity and finite plane elasticity. The correctness of the solution is verified by comparison with existing solutions and by checking an extreme situation. Our results indicate that it is permissible for the two inclusions to have different material properties and different shapes. Finally, two interesting applications of the obtained results are given, and we find that when the two inclusions have different material properties, the elastic polarization tensor associated with the two non-elliptical inclusions does not lie on the lower Hashin-Shtrikman bound. © 2011 The Author(s). Source
Wang J.,Shanghai Second Polytechnic University |
Xie H.,Shanghai Second Polytechnic University |
Xin Z.,East China University of Science and Technology |
Li Y.,Shanghai Second Polytechnic University
Carbon | Year: 2010
Four different methods, acid oxidation, mechanochemical reaction, ball milling, and grafting following acid oxidation, were used to treat multi-walled carbon nanotubes (MWCNTs). During treatment, hydroxyl groups, carboxylic groups, and amidocyanogen were introduced onto the surfaces of the MWCNTs. The MWCNTs were dispersed into palmitic acid (PA) to prepare phase change composites with high thermal conductivity. Both chemical treatment and ball milling help to break the MWCNT aggregates and to enhance their dispersibility. Measurements show that the thermal conductivity increase of the composites is highly dependent on the MWCNT pretreatment process. We propose that the difference in the interfacial thermal resistance between the MWCNTs and the matrix is due to the difference of the MWCNT surface state caused by different treatment processes. In all the MWCNT/PA composites, the one containing MWCNTs with hydroxyl groups, treated by a mechanochemical reaction, has the highest thermal conductivity increase, which, at room temperature, is up to 51.6% for a MWCNT addition of 1.0%. © 2010 Elsevier Ltd. All rights reserved. Source
Li C.,East China University of Science and Technology |
Li C.,Uppsala University |
Zhu J.,Uppsala University
Materials Letters | Year: 2013
Monodisperse Au-core silica-shell (Au@SiO2) nanoparticles demonstrated a great potential for the application of metal-enhanced fluorescence (MEF). The silica shell was doped with a novel fluorophore, Oregon Green 488-isothiocyanate (OG-488). The fluorescence of OG-488 was enhanced by Au nanoparticle core, while the silica shell was used to control the distance between OG-488 and Au surface to alleviate fluorescence quenching. The fluorescence enhancement by Au@SiO2 nanoparticles was investigated by varying SiO2 shell thickness (from 15 nm to 50 nm) and Au core diameter (40 nm, 60 nm and 80 nm). Compared with OG-488 doped silica spheres without Au core, the Au@SiO2 nanoparticles maximally gave 35-fold stronger fluorescence emission. © 2013 Elsevier B.V. All rights reserved. Source
Xu Q.F.,Shanghai JiaoTong University |
Wang J.N.,East China University of Science and Technology |
Sanderson K.D.,Pilkington Group Ltd
Journal of Materials Chemistry | Year: 2010
Superhydrophobic coatings with strong adhesion strength, high chemical stability and good self-cleaning function are fabricated by a new colloid assembly method. This method involves the utilizing of dual-sized particles to achieve a micro/nano structure, and an acidic silica sol to bond the particles with substrates. The resulting coating has a contact angle higher than 160° and a hysteresis angle of 2°, showing excellent superhydrophobic properties. The adhesion strength of the coating is proved to be strong according to the ASTM international standard. The smoothing effect of the bonders can be completely overcome by adjusting the ratios and sizes of the dual-sized silica particles. Because of its flexibility and simplicity, the present colloid assembly method may be suitable for large-scale coating. © The Royal Society of Chemistry 2010. Source
Niu Y.,East China University of Science and Technology |
Ho D.W.C.,City University of Hong Kong
IEEE Transactions on Automatic Control | Year: 2010
This technical note investigates the design of sliding mode control subject to packet losses. It is assumed that there exists a communication network in the feedback loop, and the dropout of data packet may occur. First, an estimation method is proposed to compensate the packet dropout. Subsequently, a discrete-time integral sliding surface involving dropout probability is introduced and a sliding mode controller is designed. By using the stochastic Lyapunov method, the state trajectories are shown to enter into (in mean square) a neighborhood of the specified sliding surface. Meanwhile, the stability of sliding mode dynamics is also ensured. Finally, numerical simulation example is provided. © 2006 IEEE. Source
Wang X.,East China University of Science and Technology
Zeitschrift fur Angewandte Mathematik und Physik | Year: 2015
We study the effect of surface elasticity on an arc-shaped crack in a linearly elastic isotropic homogeneous material under antiplane shear deformation. The surface mechanics is incorporated by using a continuum-based surface/interface model of Gurtin and Murdoch. We obtain a complete solution by reducing the problem to two decoupled first-order Cauchy-type singular integro-differential equations. It is shown that different from the case of a straight crack, the stresses exhibit both the weak logarithmic and the strong square root singularities at the tips of the arc crack. © 2014, Springer Basel. Source
Du D.,East China University of Science and Technology |
Duan W.-L.,CAS Shanghai Institute of Organic Chemistry
Chemical Communications | Year: 2011
Highly stereoselective asymmetric 1,4-addition of diarylphosphines to α,β-unsaturated N-acylpyrroles catalyzed by a PCP pincer-Pd complex has been developed for the synthesis of chiral phosphines with excellent stereoselectivity (91-99% ee) under mild conditions. The products obtained can be further converted into chiral phosphine-oxazoline ligands. © 2011 The Royal Society of Chemistry. Source
Fracture control over thermal-mechanical creep and fatigue crack growth in near-alpha titanium alloy
Tang K.K.,East China University of Science and Technology
Engineering Fracture Mechanics | Year: 2013
A multiscale fatigue crack growth model is proposed to analyze the thermal-mechanical effects in materials under the non-additive effects of creep and cyclic loading. On the basis of the design criterion for aircrafts, the thermal-mechanical creep and fracture crack growth of a near-alpha titanium alloy TA12 are investigated. Influences of temperature profiles and perturbation number η are also discussed. This fracture control approach offers a reference in the life design of airplanes. The objective of this research is to provide an inverse approach on health monitoring of crack growth in fracture control from the perspective of multiscaling. © 2013 Elsevier Ltd. Source
Yuan Y.,East China University of Science and Technology
Mathematical and Computer Modelling | Year: 2013
It is a very interesting topic to forecast the movement direction of financial time series by machine learning methods. Among these machine learning methods, support vector machine (SVM) is the most effective and intelligent one. A new learning model is presented in this paper, called the polynomial smooth support vector machine (PSSVM). After being solved by Broyden-Fletcher-Goldfarb-Shanno (BFGS) method, optimal forecasting parameters are obtained. The exchange rate movement direction of RMB (Chinese renminbi) vs USD (United States Dollars) is investigated. Six indexes of Dow Jones China Index Series are used as the input. 4 sections with 180 time experiments have been completed. Many results show that the proposed learning model is effective and powerful. © 2012 Elsevier Ltd. Source
Teng S.J.,Shanghai JiaoTong University |
Wang J.N.,East China University of Science and Technology |
Wang X.X.,Tongji University
Journal of Materials Chemistry | Year: 2011
Carbon nanocages (CNCs) with a hollow core and a thin wall of a few graphitic layers have a wide range of applications. However, the preparation of such a material remains a great challenge. In this study, we report the preparation of thin-walled CNCs through the pyrolysis of a mixture composed of pyridine and liquid iron pentacarbonyl, subsequent heat treatment in the presence of NH4Cl at a low temperature, and finally washing and filtering in water. The finding that pyridine is completely mutually soluble with liquid iron pentacarbonyl in any proportion stands out to be a crucial advantage for reducing the thickness of the graphitic wall formed on a metal core. To obtain hollow CNCs, heat-treatment proves to be simple and effective in removing the metal core and, more importantly, maintaining the thin graphitic wall when compared with conventional boiling in a strong oxidant, such as HNO3. The thin-walled hollow CNCs are demonstrated to be suitable nanocontainers for encapsulating iodine, as iodine can easily get into and out of the CNCs when it is heated at a relatively low temperature. Considering the large internal space and thin graphitic wall, the hollow CNCs could be widely used in many fields, such as biology, medicine and chemistry. © 2011 The Royal Society of Chemistry. Source
Zhang Y.,East China University of Science and Technology |
Zhang Y.,Desert Research Institute |
Obrist D.,Desert Research Institute |
Zielinska B.,Desert Research Institute |
Gertler A.,Desert Research Institute
Atmospheric Environment | Year: 2013
Biomass burning is a significant emission source of PM2.5(i.e., particulate matter with an aerodynamic diameter less than 2.5 μm), but few studies addressed the chemical composition of PM2.5 emissions from various types of fires. Here, we present results from a sampling campaign to quantify PM2.5 emissions from various types of prescribed burning activities using analysis of carbon (elemental carbon: EC; organic carbon: OC; and total carbon: TC); polar organic compounds (12 different compounds and four functional classes); water-soluble potassium (K+); and particle-bound mercury (PHg). Emissions were characterized for a series of prescribed burns in the Lake Tahoe basin in the western United States, along with controlled biomass combustion in a wood stove. In the field, emissions were collected from: (i) landscape underburns, consisting of wooden tissues, foliage, branches, and surface duff; (ii) pile burns, consisting mainly of wooden tissues stacked up to piles; (iii) mixed underburn/pile burns which consisted of a mix of the above; in a wood stove, burns included different fuel types collected from the Lake Tahoe basin, specifically (iv) wooden logs mainly of pine; (v) green foliage and branches from two dominant shrubs (manzanita and bitterbrush); and (vi) surface duff, mostly consisting of pine needle litter.Our data showed higher ratios of organic to elemental carbon in green fuels (19.2 ± 4.2) compared to dry, wooden logs (7.3 ± 1.9) both in prescribed burns in the field and in controlled stove combustion, indicating that more moisture in green biomass resulted in more smoldering-phase combustion. Further, OC/EC ratios were lower in wood stove burns compared to prescribed burns in the field, which we attribute to higher combustion temperatures in wood stove burns. The suite of 12 select polar organic compounds showed that the most prevalent compounds emitted across all burns were levoglucosan, mannosan, and resin acids (dehydroabietic, pimaric, and abietic acids), while emissions of inositols and arabitols were only significant in combustion of leaves from a broadleaf shrub indicating their potential use as tracers for green foliage. Water-soluble K+, a common tracer for biomass combustion, showed a clear difference between field understory burns (low K+) and wooden pile burns (nearly 5 times higher), suggesting that K+ can potentially be used for differentiating between different prescribed burning types. Finally, PHg emissions were lowest in green vegetation and underburns emissions, which was unexpected due to inherently higher Hg levels in green foliage and surface duff. Using multiple tracers (i.e., soluble potassium, carbon and mercury) allowed to separate emissions between prescribed burning, controlled stove burning, and ambient air which includes residential wood combustion. © 2013 Elsevier Ltd. Source
Ling H.,East China University of Science and Technology |
Luyben W.L.,Lehigh University
Industrial and Engineering Chemistry Research | Year: 2010
The control of a divided-wall column is more difficult than the control of a conventional two-column separation sequence for the separation of ternary mixtures because there is more interaction among control loops. In a previous paper, a control structure using four composition loops was shown to provide effective control of the purities of the three product streams and also achieve minimum energy consumption for both feed flow rate and feed composition disturbances. The numerical example studied the separation of benzene, toluene, and o-xylene. The four manipulated variables were reflux flow rate (R), side-stream flow rate (S), reboiler heat input (QR), and liquid split (βL) at the top of the wall. In this paper we explore the use of temperatures to avoid expensive and high-maintenance composition analyzers. Two types of temperature control structures are studied. In the first, three temperatures located in the main column and one temperature on the prefractionator side of the wall are used to adjust the four manipulated variables. Feed flow rate disturbances are well handled with this structure, but product purities start to deviate significantly from their desired values for feed composition changes greater than about 10%. In the second control structure, four differential temperature control loops are used. Performance is improved and disturbances of 20% in feed composition are well handled with only small deviations in product purities. This structure also handles large changes in column operating pressure. © 2010 American Chemical Society. Source
Decoration of carbon nanotubes with CdS nanoparticles by polythiophene interlinking for optical limiting enhancement
Feng M.,Fuzhou University |
Sun R.,Fuzhou University |
Zhan H.,Fuzhou University |
Chen Y.,East China University of Science and Technology
Carbon | Year: 2010
The sidewalls of multiwalled carbon nanotubes (MWCNTs) were decorated with CdS nanoparticles using a mild two-step approach, with in situ polymerized thiophene (PTh) acting as an interlinker. Extensive characterization of the materials has been carried out using transmission electron microscopy, selected area electron diffraction, X-ray diffraction, thermal gravimetric analysis, ultraviolet-visible absorption spectroscopy and photoluminescence spectroscopy. Optical limiting (OL) studies have been performed using the open Z-scan technique at the laser wavelengths of 532 and 1064 nm. The MWCNT-PTh-CdS system shows an enhanced OL effect in comparison to the pristine MWCNTs, particularly at 1064 nm. Possible underlying mechanisms are proposed based on the results of nonlinear scattering measurements. © 2009 Elsevier Ltd. All rights reserved. Source
Meng K.,Hong Kong Polytechnic University |
Wang H.G.,East China University of Science and Technology |
Dong Z.Y.,Hong Kong Polytechnic University |
Wong K.P.,Hong Kong Polytechnic University |
Wong K.P.,University of Western Australia
IEEE Transactions on Power Systems | Year: 2010
Economic load dispatch (ELD) is an important topic in the operation of power plants which can help to build up effective generating management plans. The ELD problem has nonsmooth cost function with equality and inequality constraints which make it difficult to be effectively solved. Different heuristic optimization methods have been proposed to solve this problem in previous study. In this paper, quantum-inspired particle swarm optimization (QPSO) is proposed, which has stronger search ability and quicker convergence speed, not only because of the introduction of quantum computing theory, but also due to two special implementations: self-adaptive probability selection and chaotic sequences mutation. The proposed approach is tested with five standard benchmark functions and three power system cases consisting of 3, 13, and 40 thermal units. Comparisons with similar approaches including the evolutionary programming (EP), genetic algorithm (GA), immune algorithm (IA), and other versions of particle swarm optimization (PSO) are given. The promising results illustrate the efficiency of the proposed method and show that it could be used as a reliable tool for solving ELD problems. © 2009 IEEE. Source
Tang Y.,East China University of Science and Technology
Proceedings of the IEEE International Conference on Industrial Technology | Year: 2016
This paper is concerned with robust H∞ self-triggered control of networked systems. The system considered here includes parameter uncertainties and packet dropouts. In order to compensate for the existence of deterministic packet dropouts, a new self-triggered control scheme is proposed. The main feature of the proposed self-triggered control strategy is that the next control task is predicted based on the self-triggered technique, in which the predicted event interval is divided equally for the sake of packet dropouts. The triggered condition is developed to ensure the stability of the uncertain sampled system by utilizing an uncertain algebraic Riccati equation and the comparison principle. Finally, an example of the inverted pendulum of a cart is provided to illustrate the effectiveness of the proposed results. © 2016 IEEE. Source
Liu G.,CAS Shenyang Institute of Metal Research |
Liu G.,University of Queensland |
Wang L.,University of Queensland |
Yang H.G.,East China University of Science and Technology |
And 2 more authors.
Journal of Materials Chemistry | Year: 2010
Semiconductor photocatalysts have important applications in renewable energy and environment fields. To overcome the serious drawbacks of low efficiency and narrow light-response range in most stable semiconductor photocatalysts, many strategies have been developed in the past decades. This review attempts to provide a comprehensive update and examination of some fundamental issues in titania (TiO2)-based semiconductor photocatalysts, such as crystal growth, doping and heterostructuring. We focus especially on recent progress in exploring new strategies to design TiO 2-based photocatalysts with unique structures and properties, elucidating the chemical states and distribution of dopants in doped TiO 2, designing and fabricating integrated heterostructure photocatalysts with different charge-carrier transfer pathways, and finally identifying the key factors in determining the photocatalytic efficiency of titania-based photocatalysts. © 2010 The Royal Society of Chemistry. Source
Gong J.,North Dakota State University |
Sumathy K.,North Dakota State University |
Liang J.,East China University of Science and Technology
Renewable Energy | Year: 2012
A gel polymer electrolyte containing I-/I3 - redox couple was prepared using polyethylene glycol (PEG) as polymer matrix and propylene carbonate (PC) as organic solvent by sol-gel method. A dye sensitized solar cell (DSSC) employing the gel polymer electrolyte gives an open-circuit voltage of 0.7 V and a short-circuit current of 8.1 mA cm-2 at an incident light intensity of 100 mW cm-2. Fourier transform infrared spectroscopy was utilized to examine the chemical properties of produced gel electrolytes. Unlike the conventional covalent bond that bridges the different polymer segments, in this study, it was observed that hydrogen bonds bridged polyethylene glycol and propylene carbonate. Influences of different synthetic parameters such as reaction time and temperature were also investigated. Optimal DSSC performance was observed at electrolyte reaction temperature and time of 100 °C and 24 h, respectively, with a maximum photoelectric energy conversion efficiency of 2.2%. © 2011. Source
Zhang W.,University of Bayreuth |
Zhang W.,East China University of Science and Technology |
Muller A.H.E.,University of Bayreuth
Polymer | Year: 2010
Copper-catalyzed alkyne-azide "click chemistry" is applied in the preparation of tadpole-shaped ("monochelic") POSS-end functional hybrid polymers by combining with ATRP and RAFT polymerization. Alkyne-functionalized ATRP initiator and RAFT agent were respectively synthesized and applied in the preparation of alkyne-terminal poly(methyl methacrylate) and polystyrene. The tadpole-shaped POSS-containing hybrid polymers are easily obtained by the click reaction with an azido-functional POSS molecule. This presents a novel and effective method to prepare POSS-containing hybrid polymers. © 2010 Elsevier Ltd. All rights reserved. Source
Asymmetric cyclization reactions of allenoates with imines or α,β-unsaturated ketones catalyzed by organocatalysts derived from cinchona alkaloids
Pei C.-K.,CAS Shanghai Institute of Organic Chemistry |
Shi M.,East China University of Science and Technology
Chemistry - A European Journal | Year: 2012
Lewis base-catalyzed cyclization reactions of allenoates with electron-deficient olefins and imines have been demonstrated by the preparation of biologically active natural products and pharmaceutically interesting substances and have emerged as powerful synthetic tools in the rapid construction of cyclic molecular complexity. In contrast to phosphine-containing Lewis bases, nitrogen-containing Lewis base amines display markedly different reaction profiles; however, this area is not well-developed. Herein we summarize the recent progress in this emerging field and outline the challenges ahead. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
A green, efficient, and rapid procedure for the synthesis of 2-amino-3-cyano-1,4,5,6-tetrahydropyrano[3,2-c]quinolin-5-one derivatives catalyzed by ammonium acetate
Lei M.,CAS Shanghai Institute of Materia Medica |
Ma L.,East China University of Science and Technology |
Hu L.,CAS Shanghai Institute of Materia Medica
Tetrahedron Letters | Year: 2011
A green, efficient, and rapid procedure for the synthesis of 2-amino-3-cyano-1,4,5,6-tetrahydropyrano[3,2-c]quinolin-5-one derivatives has been developed by one-pot condensation of 4-hydroxyquinolin-2(1H)-one, aldehyde, and malononitrile in the presence of ammonium acetate in EtOH. This method has the advantages of operational simplicity, mild reaction conditions, short reaction time, and little environmental impact. © 2011 Elsevier Ltd. All rights reserved. Source
Zhao M.-Q.,Drexel University |
Ren C.E.,Drexel University |
Ling Z.,Drexel University |
Ling Z.,Dalian University of Technology |
And 6 more authors.
Advanced Materials | Year: 2015
Free-standing and flexible sandwich-like MXene/carbon nanotube (CNT) paper, composed of alternating MXene and CNT layers, is fabricated using a simple filtration method. These sandwich-like papers exhibit high volumetric capacitances, good rate performances, and excellent cycling stability when employed as electrodes in supercapacitors. © 2014 Wiley-VCH Verlag GmbH & Co. KGaA. Source
Li F.,East China University of Science and Technology
Neurocomputing | Year: 2014
This paper studies the global stability at some limit cycle of a switched Boolean network by using the semi-tensor product method. The switched Boolean network is introduced and expressed into an algebraic form. Then, the switching-incidence matrix is constructed and the physical meaning is given. Based on this, a necessary and sufficient condition for the global stability at some limit cycle of the switched Boolean network is given. An illustrative example shows the efficiency of the proposed results. © 2014 Elsevier B.V. Source
Neural-network-based output-feedback adaptive dynamic surface control for a class of stochastic nonlinear time-delay systems with unknown control directions
Yu Z.,East China University of Science and Technology |
Li S.,Shanghai JiaoTong University
Neurocomputing | Year: 2014
This paper focuses on the problem of output-feedback adaptive stabilization for a class of stochastic nonlinear time-delay systems with unknown control directions. First, based on a linear state transformation, the unknown control coefficients are lumped together and the original system is transformed to a new system for which control design becomes feasible. Then, after the introduction of an observer, an adaptive neural network (NN) output-feedback control scheme is presented for such systems by using dynamic surface control (DSC) technique and Lyapunov-Krasovskii method. The designed controller ensures that all the signals in the closed-loop system are 4-Moment (or 2-Moment) semi-globally uniformly ultimately bounded. Finally, a numerical example is given to demonstrate the feasibility and effectiveness of the proposed control design. © 2013 Elsevier B.V. Source
Su C.,East China University of Science and Technology
Journal of Combinatorial Optimization | Year: 2013
We consider two parallel machines scheduling problems with a single server. For the general case we present an online LPT algorithm with competitive ratio 2, and give a lower bound √5+1/2. We also apply the online LPT algorithm to the special case where all the setup times are equal to 1. We show that the competitive ratio is 1.5, and no online algorithm can has a competitive ratio less than √2. © 2011 Springer Science+Business Media, LLC. Source
Xie H.,East China University of Science and Technology
BIT Numerical Mathematics | Year: 2012
An iterative method is proposed to compute partial derivatives of eigenvectors of quadratic eigenvalue problems with respect to system parameters. Convergence theory of the proposed method is established. Numerical experiments demonstrate that the proposed method can be used efficiently for partial derivatives of eigenvectors corresponding to dominant eigenvalues. © 2011 Springer Science + Business Media B.V. Source
Long-range interaction of a line dislocation with multiple multicoated inclusions of arbitrary shape
Wang X.,East China University of Science and Technology |
Zhou K.,Nanyang Technological University
Acta Mechanica | Year: 2013
We investigate the long-range elastic interaction of a line dislocation with multiple multicoated two-dimensional inclusions of arbitrary shape. Approximate closed-form solutions are found for the following two situations: (i) an edge dislocation in a composite with all the phases having equal shear modulus but different Poisson's ratios and (ii) a screw dislocation interacting with an inclusion of arbitrary shape with a properly designed coating layer. The far-field asymptotic expressions of the image force on the dislocation can then conveniently be derived. © 2012 Springer-Verlag Wien. Source
Wang X.,East China University of Science and Technology |
Zhou K.,Nanyang Technological University
International Journal of Engineering Science | Year: 2013
We investigate the internal electroelastic field within a three-phase piezoelectric inclusion of arbitrary shape when the piezoelectric matrix is subjected to remote uniform electroelastic loadings. It is observed that in the presence of the intermediate interphase layer, the internal electroelastic field within an inclusion of non-elliptical shape can be conditionally or unconditionally uniform. In order to ensure that the internal electroelastic field is conditionally uniform, the thickness of the interphase layer should be properly designed for given electroelastic constants of the three-phase piezoelectric composite, and the remote uniform electric displacements should be dependent on the applied remote uniform stresses. To ensure an unconditionally uniform internal electroelastic field, the electroelastic constants of the interphase layer can be uniquely determined by given thickness of the interphase layer and given electroelastic constants of both the internal inclusion and the surrounding matrix. Interestingly, our analysis indicates that even in the absence of the interphase layer, the internal electroelastic field within a piezoelectric inclusion of arbitrary shape can still be conditionally uniform if the electroelastic constants of the two-phase composite satisfy a restriction. © 2012 Elsevier Ltd. All rights reserved. Source
Wang L.,Shanghai Institute of Technology |
Shi H.,East China University of Science and Technology
Chinese Journal of Chemical Engineering | Year: 2014
In this paper, an improved nonlinear process fault detection method is proposed based on modified kernel partial least squares (KPLS). By integrating the statistical local approach (SLA) into the KPLS framework, two new statistics are established to monitor changes in the underlying model. The new modeling strategy can avoid the Gaussian distribution assumption of KPLS. Besides, advantage of the proposed method is that the kernel latent variables can be obtained directly through the eigen value decomposition instead of the iterative calculation, which can improve the computing speed. The new method is applied to fault detection in the simulation benchmark of the Tennessee Eastman process. The simulation results show superiority on detection sensitivity and accuracy in comparison to KPLS monitoring. © 2014 Chemical Industry and Engineering Society of China (CIESC) and Chemical Industry Press (CIP). Source
Effects of processing conditions on the mechanical properties and deformation behaviors of plasma-sprayed thermal barrier coatings: Evaluation of residual stresses and mechanical properties of thermal barrier coatings on the basis of in situ curvature measurement under a wide range of spray parameters
Zhang X.,Japan National Institute of Materials Science |
Zhang X.,East China University of Science and Technology |
Watanabe M.,Japan National Institute of Materials Science |
Kuroda S.,Japan National Institute of Materials Science
Acta Materialia | Year: 2013
A modified analytical model has been developed to describe the nonlinear elastic response and residual stress in plasma sprayed thermal barrier coatings (TBCs) on the basis of the measured curvature-temperature plot during the spraying process. Evolution of residual stresses and the nonlinear stress-strain relation of the coating during the cooling stage after deposition were identified and the strain-dependent coating modulus was obtained. Wide ranges of deposition temperature from 200 to 850 °C as well as that of passage thickness from 6 to 58 μm were explored in the experiments because significant changes in the TBC microstructure could be expected. The analyzed results were related to the processing parameters in spraying, such as the substrate temperature and passage thickness. A complicated interplay among the coating microstructure, residual stresses and mechanical properties was identified. Generally with increasing deposition temperature or passage thickness, denser microstructures were observed with an increase in elastic modulus. The nonlinear strain-stress curves of TBCs indicated that the coating modulus increased with compressive residual stress due to closing of microcracks and inter-splat sliding. Moreover, the coating modulus depended not only on the magnitude of residual stress but also on the coating thickness and it was found that the axial force, which is the product of the residual stress and coating thickness, could be used to express their synergistic effect. © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. Source
Sheng C.,Shanghai University |
Dong G.,Shanghai University |
Miao Z.,Shanghai University |
Zhang W.,Shanghai University |
And 2 more authors.
Chemical Society Reviews | Year: 2015
Targeting protein-protein interactions (PPIs) has emerged as a viable approach in modern drug discovery. However, the identification of small molecules enabling us to effectively interrupt their interactions presents significant challenges. In the recent past, significant advances have been made in the development of new biological and chemical strategies to facilitate the discovery process of small-molecule PPI inhibitors. This review aims to highlight the state-of-the-art technologies and the achievements made recently in this field. The "hot spots" of PPIs have been proved to be critical for small molecules to bind. Three strategies including screening, designing, and synthetic approaches have been explored for discovering PPI inhibitors by targeting the "hot spots". Although the classic high throughput screening approach can be used, fragment screening, fragment-based drug design and newly improved virtual screening are demonstrated to be more effective in the discovery of PPI inhibitors. In addition to screening approaches, design strategies including anchor-based and small molecule mimetics of secondary structures involved in PPIs have become powerful tools as well. Finally, constructing new chemically spaced libraries with high diversity and complexity is becoming an important area of interest for PPI inhibitors. The successful cases from the recent five year studies are used to illustrate how these approaches are implemented to uncover and optimize small molecule PPI inhibitors and notably some of them have become promising therapeutics. © The Royal Society of Chemistry. Source
Interaction of a screw dislocation with an interface and a nanocrack incorporating surface elasticity
Wang X.,East China University of Science and Technology
Zeitschrift fur Angewandte Mathematik und Physik | Year: 2015
We study the anti-plane deformations of a linearly elastic bimaterial. One phase of the bimaterial is weakened by a finite crack with surface elasticity perpendicular to the interface and is also subjected to a screw dislocation. The surface elasticity is incorporated by using a version of the continuum-based surface/interface model of Gurtin and Murdoch. By considering a distribution of screw dislocations and line forces on the crack, the interaction problem is reduced to two decoupled first-order Cauchy singular integro-differential equations, which can be numerically solved by means of the Chebyshev polynomials and the collocation method. The associated problem of a mode III Zener–Stroh crack perpendicular to a bimaterial interface is also solved. © 2015, Springer Basel. Source
Sun W.,Hangzhou Dianzi University |
Sun W.,East China University of Science and Technology
Physica Scripta | Year: 2013
For deterministically growing networks, it is a theoretical challenge to determine the topological properties and dynamical processes. In this paper, we study random walks on generalized Koch networks with features that include an initial state that is a globally connected network to r nodes. In each step, every existing node produces m complete graphs. We then obtain the analytical expressions for first passage time (FPT), average return time (ART), i.e. the average of FPTs for random walks from node i to return to the starting point i for the first time, and average sending time (AST), defined as the average of FPTs from a hub node to all other nodes, excluding the hub itself with regard to network parameters m and r. For this family of Koch networks, the ART of the new emerging nodes is identical and increases with the parameters m or r. In addition, the AST of our networks grows with network size N as N ln N and also increases with parameter m. The results obtained in this paper are the generalizations of random walks for the original Koch network. © 2013 The Royal Swedish Academy of Sciences. Source
Effects of local thermal non-equilibrium on the pore pressure and thermal stresses around a spherical cavity in a porous medium
He L.-W.,East China University of Science and Technology |
Jin Z.-H.,University of Maine, United States
International Journal of Engineering Science | Year: 2011
In this paper, we use a local thermal non-equilibrium (LTNE) thermo-poroelasticity theory to investigate temperatures, pore pressure and thermal stresses around a spherical cavity in an infinite fluid saturated porous medium. In the LTNE theory, the solid and fluid phases undergo different temperature variations which induce additional pore pressure and thermal stresses. The asymptotic short time solutions of temperature, pore pressure and thermal stresses are obtained using the Laplace transform technique. Numerical results for two porous materials (clay and sandstone) are presented to examine the effects of LTNE on the temperature, pore pressure and thermal stresses around the spherical cavity. The results show that for the clay, the LTNE radial stress has a significantly larger peak value (magnitude) than that of the classical radial stress. The influence of LTNE on the pore pressure and tangential stress, however, are marginal. For the sandstone, both the radial stress (magnitude) and pore pressure are significantly increased by the LTNE effect. © 2010 Elsevier Ltd. All rights reserved. Source
Three-phase inclusions of arbitrary shape with internal uniform hydrostatic stresses in finite elasticity
Wang X.,East China University of Science and Technology |
Schiavone P.,University of Alberta
Journal of Applied Mechanics, Transactions ASME | Year: 2012
We study the internal stress field of a three-phase two-dimensional inclusion of arbitrary shape bonded to an unbounded matrix through an intermediate interphase layer when the matrix is subjected to remote uniform in-plane stresses. The elastic materials occupying all three phases belong to a particular class of compressible hyperelastic harmonic materials. Our analysis indicates that the internal stress field can be uniform and hydrostatic for some nonelliptical shapes of the inclusion, and all of the possible shapes of the inclusion permitting internal uniform hydrostatic stresses are identified. Three conditions are derived that ensure an internal uniform hydrostatic stress state. Our rigorous analysis indicates that for the given material and geometrical parameters of the three-phase inclusion of a nonelliptical shape, at most, eight different sets of remote uniform Piola stresses can be found, leading to internal uniform hydrostatic stresses. Finally, the analytical results are illustrated through an example. Copyright © 2012 American Society of Mechanical Engineers. Source
Hydrothermal fabrication of Ni3S2/TiO2 nanotube composite films on Ni anode and application in photoassisted water electrolysis
Chen A.,East China University of Science and Technology
Journal of Alloys and Compounds | Year: 2013
Nanostructured films of rhombohedral Ni3S2 were hydrothermally synthesized on Ni and TiO2 nanotube layer, as substrates. A possible mechanism is proposed to explain the formation of rhombohedral Ni3S2 nanostructures. The results of UV-vis spectrophotometric studies indicate that optical absorption spectrum of Ni 3S2/TiO2 nanotube composites could be extended to the visible region. As-synthesized Ni3S2/TiO 2 nanotube composite films on Ni substrate had better (by about 40%) hydrogen production performance under the visible light irradiation, in comparison with the Ni anode modified by TiO2 nanotubes. © 2013 Elsevier B.V. All rights reserved. Source
Wang X.,East China University of Science and Technology
Acta Mechanica | Year: 2011
This research contains two relevant parts. In the first part, we investigate the problem of an edge dislocation interacting with a thickly coated circular inclusion. Both interface slip and diffusion occur on the inclusion/coating and coating/matrix interfaces. We further assume that all these stress relaxation processes on the two interfaces have come to an end. A closed-form solution to the problem is derived. It is observed that: (i) the dislocation will induce an internal uniform hydrostatic stress field within the three-phase circular inclusion; (ii) the dislocation will induce the same uniform rigid body rotation within the inclusion and within the coating layer; and (iii) when a compliant coating layer is thick enough, there exists no climb repulsion region. In the second part, an exact solution to the problem of an edge dislocation inside a circular inclusion with a fully relaxed interface is obtained. We observe that the climb force on the dislocation tends to keep it at the center of the inclusion. © 2011 Springer-Verlag. Source
Three-phase elliptical inclusions with internal uniform hydrostatic stresses in finite plane elastostatics
Wang X.,East China University of Science and Technology
Acta Mechanica | Year: 2011
We consider the internal stress field of a three-phase elliptical inclusion bonded to an infinite matrix through an interphase layer when the matrix is subjected to remote uniform stresses. The elastic materials comprising all the three phases belong to a particular class of harmonic materials, and the formed interfaces are two confocal ellipses. A condition leading to internal uniform hydrostatic stresses is derived. This condition relates the two remote principal stresses with the geometric parameters (the thickness of the interphase layer and the aspect ratio of the elliptical inclusion) of the three-phase elliptical inclusion. When this condition is met, the hoop stress in the interphase layer along the entire interphase/inclusion interface is also uniform. Five special situations of practical importance are discussed in considerable detail to demonstrate the unique phenomena inherent in harmonic materials. Our discussions indicate that when this condition is met, it is permissible for the two remote principal stresses to have opposite signs and that for given geometric and material parameters, the remote loading ratio is no longer constant and multiple external loading states exist leading to internal uniform hydrostatic stresses. It is found that this condition can be written into a hyperbola for the two remote principal stresses when the interphase layer is extremely compliant or relatively stiff or when the inclusion is almost rigid. When the magnitudes of the remote stresses are sufficiently large, this condition becomes a very simple one relating the remote loading ratio with the geometric parameters of the composite. Interestingly, it is clearly observed from the simple condition that for given geometric parameters of the three-phase elliptical inclusion, there exist two different values of the remote loading ratio, both of which lead to an internal uniform hydrostatic stress state. © 2011 Springer-Verlag. Source
Wang E.,Chalmers University of Technology |
Ma Z.,Linkoping University |
Zhang Z.,Chalmers University of Technology |
Zhang Z.,East China University of Science and Technology |
And 5 more authors.
Journal of the American Chemical Society | Year: 2011
A new, low-band-gap alternating copolymer consisting of terthiophene and isoindigo has been designed and synthesized. Solar cells based on this polymer and PC71BM show a power conversion efficiency of 6.3%, which is a record for polymer solar cells based on a polymer with an optical band gap below 1.5 eV. This work demonstrates the great potential of isoindigo moieties as electron-deficient units for building donor-acceptor-type polymers for high-performance polymer solar cells. © 2011 American Chemical Society. Source
Energy spectrum of the Manning-Rosen potential including centrifugal term solved by exact and proper quantization rules
Gu X.-Y.,East China University of Science and Technology |
Dong S.-H.,National Polytechnic Institute of Mexico
Journal of Mathematical Chemistry | Year: 2011
The energy spectrum of the Manning-Rosen potential including centrifugal term in higher dimensions is presented by exact quantization rule approach. The result is compared with that by proper quantization rule method. It is found that the latter is better than that of the exact quantization rule. We find that the interdimensional degeneracy exists for the states in different dimensions. For the special case D = 3, the results agree well with those obtained by other methods. © 2011 Springer Science+Business Media, LLC. Source
Liu J.,East China University of Science and Technology
Zhongguo ji sheng chong xue yu ji sheng chong bing za zhi = Chinese journal of parasitology & parasitic diseases | Year: 2012
To compare the effect and acted target of auranofin on juvenile and adult Schistosoma japonicum, and detect the cytotoxicity of auranofin against host cells. Effect of auranofin on the recombinant SjTrx-1 enzyme activity was investigated with dithiothreitol (DTU)/insulin reduction method. Female Kunming mice (4-6 weeks old) were infected (10 mice with 600-800 cercariae per mice for schistosomula and other 10 mice with 80-100 cercariae per mice for adult worms) and sacrificed after 15 d and 35 d post-infection for worm collection. The perfused worms were washed with sterile saline thoroughly and transformed into 12-well Falcon plate containing 4 ml medium each well. Auranofin or praziquantel was added with different final concentrations (1, 5 and 10 microg/ml). The morphological alternations and number of death worms were observed microscopically at the defined time points of 2, 24, 48 and 72 h, respectively. CCK-8 kit was used to analyze the cytotoxicity of auranofin against 3 different host cells (Hep G2, 293T and Hela). 10 microg/ml auranofin reduced the recombinant SjTrx-1 activity by 54.5% in 40 min. 5 microg/ml auranofin resulted in 75% mortality of adult worms after 24h, but no schistosomulum was dead in the same period. Although the auranofin concentration increased to 10 microg/ml resulted in the death of all worms in 72 h, the death of schistosomula was delayed in comparison to that of the adults. When treated with auranofin or praziquantel, the worms contracted, convoluted and became gloomy under optical microscope while scanning electron microscopy showed that the tegument structure was severely damaged for both of them. Cytotoxicity analysis showed that 5 microg/ml auranofin reduced the relative activity by 85% than the control group and nearly 100% cell death when the concentration increased to 10 microg/ml. SjTrx-1 is one of auranofin acting targets. Auranofin exhibits strong cytotoxicity against host cells, with more significant effect on adults than juveniles. Source
Hu H.,East China University of Science and Technology |
Wang X.,Shanghai JiaoTong University
Physica A: Statistical Mechanics and its Applications | Year: 2012
We study the detailed growth of a social networking site with full temporal information by examining the creation process of each friendship relation that can collectively lead to the macroscopic properties of the network. We first study the reciprocal behavior of users, and find that link requests are quickly responded to and that the distribution of reciprocation intervals decays in an exponential form. The degrees of inviters/accepters are slightly negatively correlative with reciprocation time. In addition, the temporal feature of the online community shows that the distributions of intervals of user behaviors, such as sending or accepting link requests, follow a power law with a universal exponent, and peaks emerge for intervals of an integral day. We finally study the preferential selection and linking phenomena of the social networking site and find that, for the former, a linear preference holds for preferential sending and reception, and for the latter, a linear preference also holds for preferential acceptance, creation, and attachment. Based on the linearly preferential linking, we put forward an analyzable network model which can reproduce the degree distribution of the network. The research framework presented in the paper could provide a potential insight into how the micro-motives of users lead to the global structure of online social networks. © 2011 Elsevier B.V. All rights reserved. Source
East China University of Science and Technology | Date: 2014-01-10
Provided herein are Raman active particles and methods for their preparation and use. The particles can include a SERS-active material that is at least partially encased within a spherical porous hollow casing. In some embodiments, this can be especially advantageous when employed for water analysis and/or being employed in combination with silica particles
High-strength carbon nanotube fibre-like ribbon with high ductility and high electrical conductivity
Wang J.N.,East China University of Science and Technology |
Luo X.G.,Shanghai JiaoTong University |
Wu T.,Shanghai JiaoTong University |
Chen Y.,Shanghai JiaoTong University
Nature Communications | Year: 2014
Macroscopic fibres made up of carbon nanotubes exhibit properties far below theoretical predictions and even much lower than those for conventional carbon fibres. Here we report improvements of mechanical and electrical properties by more than one order of magnitude by pressurized rolling. Our carbon nanotubes self-assemble to a hollow macroscopic cylinder in a tube reactor operated at high temperature and then condense in water or ethanol to form a fibre, which is continually spooled in an open-air environment. This initial fibre is densified by rolling under pressure, leading to a combination of high tensile strength (3.76-5.53 GPa), high tensile ductility (8-13%) and high electrical conductivity ((1.82-2.24) × 10 4 S cm 1). Our study therefore demonstrates strategies for future performance maximization and the very considerable potential of carbon nanotube assemblies for high-end uses. © 2014 Macmillan Publishers Limited. Source
He W.,East China University of Science and Technology |
Cao J.,Nanjing Southeast University
IET Control Theory and Applications | Year: 2011
In this study, the lth order (l≥2) consensus problem for multi-agent systems is considered, which generalises the existing second-order consensus algorithm. A linear consensus protocol is proposed for solving such a consensus problem, which includes two parts: a feedback controller and interactions from the neighbours. A sufficient and necessary condition for consensus in high-order systems is obtained. As special cases, criteria for second- and third-order systems are given, in which the exact relationship between feedback gain and system parameters is established. Finally, numerical simulations are reported to illustrate the effectiveness of this protocol. © 2011 The Institution of Engineering and Technology. Source
Xia Q.,Fudan University |
Mao Y.,Fudan University |
Wu J.,East China University of Science and Technology |
Shu T.,Fudan University |
Yi T.,Fudan University
Journal of Materials Chemistry C | Year: 2014
Low molecular weight two-component gels were obtained from naphthalene diimide undecanoic acid mixed with several aliphatic and aromatic diamines. The gelation properties, structural characteristics and fluorescence of these two-component gels were studied via scanning electron microscopy, X-ray diffraction and spectroscopy. Specifically, the gel containing diaminoanthraquinone (DAQ) was sensitive to nitrite anions. The absorbance and emission intensity of the gel in the visible range obviously decreased upon addition of an aqueous solution of sodium nitrite. The faded gel collapsed and changed to a sediment after detection and the organic acid could be recycled. Te NO2 - detection with the gel provides a convenient method of nitrite analysis that is visible to the "naked eye". © 2014 The Royal Society of Chemistry. Source
New self-nanoemulsifying drug delivery system (SNEDDS) with amphiphilic diblock copolymer methoxy poly (ethylene glycol)-block-poly (ε-caprolactone).
Ren F.,East China University of Science and Technology
Pharmaceutical development and technology | Year: 2013
The objective of the study is to prepare a new self-nanoemulsifying drug delivery system (SNEDDS) with amphiphilic diblock copolymers methoxy poly (ethylene glycol)-block-poly (ε-caprolactone) (MPEG-b-PCL) and to investigate the effect of MPEG-b-PCL on the characteristics of SNEDDS. MPEG-b-PCL was synthesized and characterized by (1)H-NMR, IR and GPC. Various ratios of MPEG-b-PCL copolymers and Tween 80 were used as emulsifier to prepare the new SNEDDS. SNEDDS with high oil and low surfactant content forms a semi-solid gel at room temperature, which could be effectively sealed in soft or hard capsules. The mean droplet size of SNEDDS-generated nanoemulsions significantly decreased after the addition of diblock polymer and increased with increase of PCL chain in MPEG-b-PCL. The drug Coenzyme Q10 (CoQ10) was chosen as the model compound in this study due to its insolubility in water. CoQ10 from SNEDDS was rapidly dissolved regardless of the fluid condition. Source
Sih G.C.,Lehigh University |
Sih G.C.,East China University of Science and Technology
Theoretical and Applied Fracture Mechanics | Year: 2010
Systems with parts that vary in size from pico to macro inclusive are vulnerable of being incapacitated when a single part fails owing to deterioration of material properties. The majority of system failure can be attributed to incompatibility of integrated parts that were designed individually for general purpose. Total reliability calls for all parts, small and large, to be compatible in life spans. Mass, when regarded as energized matter, can vary as a function of time. This, in retrospect, explains why non-equilibrium and non-homogeneity cannot be avoided for multiscale shifting laws. A consistent and scale invariant definition of energy dissipation gives rise to mass pulsation, a common mechanism that seems to be applicable to living and non-living organisms. Scale shifting laws are developed from the use of transitional functions R j j+1 that stand for the mass ratios related to absorption energies W j j+1 and dissipation energies D j j+1. The notations j and j+. 1 stand for two successive scales: pi-na, na-mi, and mi-ma. Hence, the mass ratios R pi na,R na mi, and R mi ma can be referred to as the transitional inhomogeneity coefficients. They make up the scale shifting laws W j j+1=R j j+1D j j+1. Connection of the accelerated test data at the different scales, say from pico to nano to micro to macro, can be made by application of the definition of a scale invariant energy density dissipation function. On physical grounds, the segmented non-equilibrium and non-homogeneous test data can be connected through a velocity dependent mass and energy relation. Energy and power efficiency are defined to explore the macroscopic experiences to those at the lower scales. The time evolution properties of the material can also be derived as a package to include the accelerated test data, a procedure normally referred to as validation. The separation of derive-first and test-later, can never be abridged without ambiguities. Hence, total reliability of a system with many parts is advocated by judiciously matching the nine primary variables consisting of the initial disorder sizes, the time rates, and increments of the absorbed and dissipated energy density. The nine controllable variables consisting of life span distribution, energy, and power efficiencies for the three scale ranges are of secondary consideration. © 2010 Elsevier Ltd. Source
Xu Y.,East China University of Science and Technology |
Bisi A.,Purdue University
Operations Research Letters | Year: 2012
We study the wholesale-price contract with retail price-postponement in a supply chain consisting of one manufacturer and one retailer. For additive and multiplicative demand models, we establish sufficient conditions for the unimodality of profit functions and derive unique optimal solutions. We also extend existing results on the fixed retail price case and a revenue management problem. © 2012 Elsevier B.V. All rights reserved. Source
Tailoring plasmonic nanostructures for optimal SERS sensing of small molecules and large microorganisms
Xu J.,University of Washington |
Zhang L.,University of Washington |
Gong H.,East China University of Science and Technology |
Homola J.,Academy of Sciences of the Czech Republic |
Yu Q.,University of Washington
Small | Year: 2011
Local electric fields can be tuned dramatically by varying the diameter of quasi-3D gold plasmonic nanostructure arrays, as indicated by 3D finite-difference time-domain calculations. Utilizing quasi-3D arrays that exhibit a maximum electric field intensity (i.e., a "hot" spot) either at the bottom (gold nanodisks) or on the top (gold film patterned with nanoholes), the optimal surface-enhanced Raman scattering (SERS) sensitivity for the detection of small molecules or large microorganisms can be achieved. The precisely fabricated and optimized SERS-active quasi-3D nanostructure arrays make it possible to quantitatively and reproducibly detect chemical and biological species using SERS, leading to a new sensing platform with molecular specificity based on SERS for many important applications. Local electric fields can be tuned dramatically by varying the diameter of quasi-3D gold plasmonic nanostructure arrays, as indicated by 3D finite-difference time-domain calculations. Utilizing quasi-3D arrays that exhibit a maximum electric field intensity either at the bottom (gold nanodisks) or on the top (gold film patterned with nanoholes), the optimal surface-enhanced Raman scattering sensitivity for the detection of small molecules or large microorganisms can be achieved. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Facile construction of multicompartment multienzyme system through layer-by-layer self-assembly and biomimetic mineralization
Shi J.,Tianjin University of Technology |
Zhang L.,Tianjin University of Technology |
Jiang Z.,Tianjin University of Technology |
Jiang Z.,East China University of Science and Technology
ACS Applied Materials and Interfaces | Year: 2011
In nature, some organelles such as mitochondria and chloroplasts possess multicompartment structure, which render powerful and versatile performance in cascade conversion, selective separation, and energy transfer. In this study, mitochondria-inspired hybrid double membrane microcapsules (HDMMCs) were prepared through synergy between biomimetic mineralization and layer-by-layer (LbL) self-assembly using double templating strategy. The organic inner membrane was acquired via LbL self-assembly of oxidized alginate (o-alginate) and protamine on the CaCO3 template, the silica template layer was then formed onto the inner membrane through biomimetic silicification using protamine as inducer and silicate as precursor, the organic-inorganic hybrid outer membrane was acquired via biomimetic mineralization of titanium precursor. After the CaCO3 template and the silica template are removed subsequently, multicompartment microcapsules with microscale lumen and nanoscale intermembrane space were obtained. The double membrane structure of the HDMMCs was verified by high resolution scanning electron microscopy (HRSEM), and the superior mechanical stability of HDMMCs was demonstrated by osmotic pressure experiment and fluorescence microscopy. A multienzyme system was constructed by following this protocol: the first enzyme was encapsulated in the lumen of the HDMMCs, whereas the second enzyme was encapsulated in the intermembrane space. Compared to encapsulated multienzyme in single-compartment microcapsules (SCMCs) or in free form in aqueous solution, enzymatic activity, selectivity, and recycling stability of HDMMCs-enabled multienzyme system were significantly improved. Because of the inherent gentle and generic feature, the present study can be utilized to create a variety of compartment structures for the potential applications in chemical/biological catalysis and separation, drug/gene delivery systems, and biosensors. © 2011 American Chemical Society. Source
Perceptual audio hashing algorithm based on Zernike moment and maximum-likelihood watermark detection
Chen N.,East China University of Science and Technology |
Xiao H.-D.,Shanghai JiaoTong University
Digital Signal Processing: A Review Journal | Year: 2013
A new perceptual audio hashing algorithm based on maximum-likelihood watermarking detection is proposed in this paper. The idea is justified by the fact that the maximum-likelihood watermark detector responds similarly to perceptually close audio using a non-embedded watermark (i.e. virtual watermark). The feature vector, which is composed of the total amplitude of low-order Zernike moments of each audio frame, is modeled by the Gaussian or Rayleigh distribution. Then, the maximum-likelihood watermark detection is performed on the feature vector with the virtual watermarks generated by pseudo-random number generator to construct the hash vector. Extensive experiments over three large audio databases of different type (speech, instrumental music, and sung voice) demonstrate the efficiency of the proposed scheme in terms of discrimination, perceptual robustness and identification rate. It is also verified that the proposed scheme outperforms state-of-the-art techniques in perceptual robustness and can be applied in content-based search, successfully. © 2013 Elsevier Inc. All rights reserved. Source
Zhang H.,Tongji University |
Yan H.,East China University of Science and Technology |
Liu T.,Tongji University |
Chen Q.,Tongji University
IEEE Transactions on Fuzzy Systems | Year: 2011
The stabilization problem is investigated for continuous-time Takagi-Sugeno (T-S) fuzzy systems with time delay and impulsive effects in this paper. Some delay-independent and delay-dependent stabilization approaches are developed for both state feedback and observer-based feedback cases, which are based on the Lyapunov-Krasovskii functional approach and a parallel distributed compensation scheme. The time delay is dealt by Lyapunov theory allied with the Halanay Lemma. The restriction on the interval between each impulsive instant and output sampled instant needs not be equal to or less than a constant scalar, but it only requires an inequality satisfaction. When the impulsive effects vanish, the results can be extended to the corresponding sufficient conditions for the cases of a nonlinear continuous time-delay system with a state feedback and observer-based sampled output feedback. Finally, some examples are given to demonstrate the effectiveness of the proposed method. © 2011 IEEE. Source
East China University of Science and Technology | Date: 2011-09-30
Nanoparticles having one or more attached sensing moieties including uridine 5-triphosphate (UTP) and deoxythymidine 5-triphosphate (dTTP), are disclosed herein. These nanoparticles can, for example, be used for detection of plasticizers, such as phthalates, in the sample. Methods, kits and apparatuses using these nanoparticles for detecting plasticizers in a sample are also disclosed herein.
East China University of Science and Technology | Date: 2010-11-29
A process and device of coupling separation and purification to produce ethyl tert-butyl ether (ETBE) is provided, wherein ethanol containing 1 wt % to 15 wt % of water, and a mixture containing ETBE and ethanol are fed into the distillation-extraction coupling zone for separation and purification. Said distillation-extraction coupling zone is composed of a distillation column and an extraction column. Said process and device can achieve the cogeneration of ETBE and ethanol, and possesses high commercial values.
East China University of Science and Technology | Date: 2013-04-28
A dual frequency liquid crystal may be stabilized in the blue phase by a polymer matrix to provide an improved blue phase temperature range having a magnitude of at least about 65 C. Polymer-stabilized, blue phase dual frequency liquid crystal compositions and methods for producing polymer-stabilized, blue phase dual frequency liquid crystals are disclosed.
High-Temperature-Resistant Metal-Packaged Fiber Bragg Grating Sensor And Manufacturing Method Therefor
East China University of Science and Technology | Date: 2012-11-19
A manufacturing method for a high-temperature-resistant metal-packaged fiber Bragg grating sensor includes using a regenerated fiber Bragg grating obtained via high-temperature annealing as a sensitive element so that the grating will not be erased when used at high temperature. The method also includes using a magnetron sputtering method which makes an optical fiber and metal combine better to form on the surface of the optical fiber an adhesive layer and a conductive layer, thereby causing little damage to optical fiber because of the absence of the processes of coarsening, sensitization, etc. of electroless plating and the fact that the method is performed in an anhydrous environment. After magnetron sputtering, the method includes using an electroplating method to thicken and deposit a protective layer, and embedding the optical fiber in a flexible-structure metallic substrate through the electroplating method to achieve the all-metal package.
Calibration Method For The Brittle Fracture Assessment Parameters For Materials Based On The Beremin Model
East China University of Science and Technology | Date: 2012-11-27
A calibration method for brittle fracture assessment parameters for pressure vessel materials based on the Beremin model includes selecting at least two types of specimens of different constraints, and calculating the fracture toughness values K
Novel Supported Double Center Hybrid Polyethylene Catalyst, Process For Preparing The Same And Use Thereof
East China University of Science and Technology | Date: 2013-04-15
The present invention relates to a carriered hybrid vanadium-chromium-based catalyst, characterized in the catalyst is carriered on a porous inorganic carrier and a V active site and an organic Cr active site are present on the porous inorganic carrier at the same time. The present invention further relates to a process for producing a carriered hybrid vanadium-chromium-based catalyst. The catalyst of the present invention can be used for producing ethylene homopolymers and ethylene/-olefin copolymers. The hybrid vanadium-chromium-based catalyst can have high activity and produce polyethylene polymers having the properties of broad molecular weight distribution (Part of the products are bimodal distribution) and excellent -olefin copolymerization characteristic.
East China University of Science and Technology | Date: 2013-05-08
Method for recovering carbon fibers from carbon fiber reinforced polymer composites is provided. The recovered carbon fibers can be separable and can be substantially free of thermosetting resins. Compositions comprising said recovered carbon fibers are also provided.
East China University of Science and Technology | Date: 2012-11-15
Provided is a method of eliminating the dependence of methanol induced promoter on a single methanol carbon source for expressing foreign polypeptide. The method comprises activating the expression of the promoter requiring methanol induction by increasing the expression quantity of Mit1 polypeptide in cells of methylotrophic yeast, so that the promoter originally depending on methanol induction no longer depends on single methanol and can also express foreign polypeptide.
East China University of Science and Technology | Date: 2013-04-02
Provided are a pteridine ketone derivative used as an EGFR, BLK, and FLT3 inhibitor and applications thereof. Specifically, provided are a compound of the following formula I, a pharmaceutical composition containing the compound of the formula I, and use of compound in preparing medicine for treating diseases mediated by EGFR, BLK, or FLT3 or inhibiting EGFR, BLK, and FLT3.
Supported Metal Oxide Double Active Center Polyethylene Catalyst, Process For Preparing The Same And Use Thereof
East China University of Science and Technology | Date: 2013-04-19
The present invention relates to a supported hybrid vanadium-chromium-based catalyst, characterized in the catalyst is supported on a porous inorganic carrier and a V active site and a inorganic Cr active site are present on the porous inorganic carrier at the same time. The present invention further relates to a process for producing a supported hybrid vanadium-chromium-based catalyst. The invention also provides the preparation method of the catalyst, titanium or fluorine to compounds, vanadium salt and chromium salt according to the proportion, different methods of sequence and load on the inorganic carrier, after high temperature roasting, still can further add organic metal catalyst promoter prereduction activation treatment on it. The catalyst of the present invention can be used for producing ethylene homopolymers and ethylene/-olefin copolymers. The hybrid vanadium-chromium-based catalyst can have high activity and produce polyethylene polymers having the properties of broad molecular weight distribution (Part of the products are bimodal distribution) and excellent -olefin copolymerization characteristic.
Light-Switchable Gene Expression System And The Methods For Controlling Gene Expression In Prokaryotic Bacterium
East China University of Science and Technology | Date: 2013-08-01
Provided is an optically controlled gene expression system of prokaryotic bacterium, comprising: a) a photosensitive recombinant transcription factor encoding gene, the photosensitive recombinant transcription factor is one fusion protein comprising a first polypeptide as the DNA bonding domain and a second polypeptide as the photosensitive domain; b) a target transcription unit comprising promoter or promoter-reaction element or reaction element-promoter containing at least one reaction element recognized/bound by the first polypeptide and the nucleic acid sequence to be transcribed. Also provided is a prokaryotic expression vector comprising said optically controlled gene expression system, and a method for regulating gene expression in a prokaryotic host cell by using the optically controlled gene expression system. Also provided is a reagent kit containing different components of the optically controlled gene expression system. The optically controlled gene expression system of prokaryotic bacterium has a quick, effective and powerful induction, is safer than other inducers, is of little or no toxicity, and can control gene expression both spatially and temporally, and can regulate many life processes of prokaryotic bacterium.
East China University of Science, Technology and Praxair Inc. | Date: 2013-11-26
A hot oxygen nozzle and uses thereof in a gasifier, the hot oxygen nozzle comprising an outer-ring spout, a middle-ring spout, an inner-ring spout, and a central spout all sequentially and coaxially disposed, and a cooling system; the gasifier is an entrained-flow gasifier provided with one or more nozzles on a certain plane or a plurality of planes at the top or on the periphery of the gasifier body. The nozzle has a simple structure and is easy to make and maintain. A fuel gas passage is disposed inside the nozzle. Oxygen can be heated by the combustion of fuel gas; and high-temperature and high-speed oxygen can directly ignite carbonaceous materials such as coal water slurry and coke oven gas. The present invention can be applied in a gasifier and then in the final process of synthesis gas preparation.
Kunshan Tianyang Hot Melt Adhesive Co., East China University of Science, Technology and Shanghai Tianyang Hot Melt Adhesive Co. | Date: 2013-05-31
A method of preparing a composite catalyst for polyester synthesis includes the steps of: 1) sequentially dissolving a titanium compound, a silicon compound and a tin compound in an organic solvent; 2) adding a water solution of an acidic compound or of an alkaline compound in the compound from step 1) to cause hydrolysis thereof and collecting a precipitate, and washing the hydrolysis precipitate with a deionized water to obtain the composite catalyst. The catalyst is not only effective in polyester production polycondensation, but also has significant catalytic activity in esterification. The produced polyester chips all have a desirable hue.
East China University of Science and Technology | Date: 2012-06-12
A photocatalytic composition is disclosed that includes a silver halide in combination with one or more rare earth elements. The composition may be used for the photocatalytic degradation of pollutants.
Methods For Preparation Of Polyester/Glyoxalated Polyvinyl Alcohol Semi-Interpenetrating Polymer Network Hot-Melt Adhesive
Kunshan Tian Yang Hot Melt Adhesive Co., Shanghai Tian Yang Hot Melt Adhesive Co., East China University of Science and Technology | Date: 2013-06-20
A polyester/glyoxalated polyvinyl alcohol semi-interpenetrating polymer network hot-melt adhesive and preparation method therefore, mainly inlcudes the steps of: 1) transesterification of certain amounts of dimethyl terephthalate and another dibasic ester with 1,4-butanediol and other diols in the presence of an organotin catalyst under a nitrogen atmosphere in a reactor, completed upon the amount of distillation of a monohydric alcohol byproduct reaching greater than 95% of the theoretical amount; 2) after the temperature is maintained for a period of time, adding in a stabilizer and a polycondensation catalyst and incrementally increasing the temperature to trigger a polycondensation reaction under a reduced pressure to produce particles of a copolymer, and freezing and pulverizing the copolymer particles to produce a powder of a copolyester; 3) uniformly blending a polyvinyl alcohol/glyoxal mixture with the powder produced in step 2) at ambient temperature to produce the target product. The product is capable of forming an internal semi-interpenetrating network at application temperatures.
East China University of Science and Technology | Date: 2011-03-21
The present application relates to polymer-conjugated quantum dots. The quantum dots can include, for example, an inorganic core conjugated to a polymer. The quantum dots may, in some embodiments, be water-soluble and exhibit superior photoluminescence. Also disclosed are methods of making and using the quantum dots.
Shanghai Guoqiang Bioengineering Equipment Co., East China University of Science, Technology and Shanghai Cohere Electronics Technology Co. | Date: 2010-08-30
East China University of Science and Technology | Date: 2012-01-20
A general, facile, and reversible nanocrystal (NCs) phase transfer protocol via ligand exchange using nucleotides and/or nucleosides is provided to generate reversibly water-soluble nanocrystals. This phase transfer strategy can be employed on a wide variety of chemically synthesized nanostructured materials including semiconductors, metal oxides and noble metals with different sizes and shapes. The nucleotide/nucleoside-capped nanocrystals can disperse homogeneously in aqueous or alcohol media retaining, for example, high photoluminescence quantum yields. The disclosed water-soluble nanocrystals have excellent colloidal and photoluminescent stability independent on the pH and ionic strength, minimal hydrodynamic size, and are stable in cells and suitable for in vitro cell labeling, cell tracking, and other bioimaging applications.
Blue Phase Liquid Crystal Composition, Blue Phase Liquid Crystal Material And Method For Manufacturing Thereof
East China University of Science, Technology and Infovision Optoelectronics Kunshan Co. | Date: 2012-11-01
A blue phase liquid crystal material includes a liquid crystal host, a chiral reagent and a stable polymer. The chiral reagent is R811. The stable polymer is formed by photo-polymerizing a first monomer and a second monomer. The first monomer is 2-ethylhexyl acrylate (2-EHA), and the second monomer is 2-methyl-1,4-bis{4-[3(-acrylate)propoxyl]benzoicacid}phenylester (PTPTP). The blue phase liquid crystal material has a blue phase temperature range widened to an extremely low temperature. A blue phase liquid crystal composition and a method for manufacturing the blue phase liquid crystal material by using the blue phase liquid crystal composition are also provided.
East China University of Science, Technology and The Second Military Medical University | Date: 2012-04-23
A method for treatment of malaria including administering to a patient in need thereof a flavonoid glycoside compound.
East China University of Science and Technology | Date: 2011-09-22
Provided herein are Raman active particles and methods for their preparation and use. The particles can include a SERS-active material that is at least partially encased within a spherical porous hollow casing. In some embodiments, this can be especially advantageous when employed for water analysis and/or being employed in combination with silica particles
East China University of Science and Technology | Date: 2011-09-28
The present invention relates to an extensometer for measuring high-temperature structural deformations by magnification, the structure of the extensometer is that: two mounting block assemblies are mounted at the planar ends of two extension bars respectively, the top ends of the extension bars are connected tightly with the surface of a test piece, two connecting pieces are mounted at the inner sides of the two mounting block assemblies respectively, a deformation magnifying mechanism and a sensor bracket are mounted on the connecting pieces, a sensor is mounted on the sensor bracket, two connecting pieces are mounted on a same straight line, and the straight line is parallel to a straight line at which the top ends of the two extension bars are located, so as to ensure that the deformation of the test piece is delivered equally to the deformation magnifying mechanism on the connecting pieces. The present invention can measure local deformations of various metal and non-metallic structures online for a long time in real time at high temperatures, extend the deformation of the test piece at high temperatures outside of the high temperature region, and measure the deformations after they are magnified through a mechanical magnifying mechanism, thus the present invention has a very high linearity, resolution, and accuracy, meanwhile has a light structure and a small size, and is easy to install.
East China University of Science, Technology, Jiaxing Zeyuan Bio Products Co. and Shanghai Zeyuan Marine Biotechnology Co. | Date: 2013-09-26
The present invention relates to a novel method for producing astaxanthin by using microalgae. The method comprises: heterotrophic cultivation of microalgae, dilution, photo-induction, collection of microalgal cells, and extraction of astaxanthin. The method according to the present invention takes full advantages of rapid growth rate in the heterotrophic stage and fast accumulation of astaxanthin in the photo-induction stage by using a large amount of microalgal cells obtained in the heterotrophic cultivation stage, so as to greatly improve the astaxanthin production rate and thereby achieve low cost, high efficiency, large scale production of astaxanthin by using microalgae. The method not only provides an important technical means to address the large scale industrial production of astaxanthin through microalgae but also ensures an ample source of raw material for the widespread utilization of astaxanthin.
Agency: Cordis | Branch: FP7 | Program: MC-IIFR | Phase: PEOPLE-2007-4-2.IIF | Award Amount: 15.00K | Year: 2010
Lately composite materials containing metal nanoparticules have found an increasing number of applications in different fields of science and technology. In particular glasses containing metallic nanoparticules are of great interest for photonics because of their unique linear and nonlinear optical properties, which are determined by surface plasma oscillations of the metal clusters. The surface plasmon resonance depends strongly on shape, distribution and concentration of the nanoparticules, as well as on the surrounding dielectric matrix. This offers the opportunity to manufacture very promising new nonlinear materials, nanodevices and optical elements by manipulation of the nanostructural properties of the composite medium. Recently, laser-based techniques leading to modifications of shape and size of the metal clusters have increasingly become of great interest and proved to provide a very powerful and flexible tool to control and optimize the linear and nonlinear optical properties of such materials. More generally, this technique allows the engineering of the optical properties of the material via gaining control over the spatial distribution of nanoparticules in the glass matrix. The possibility to 3D spatially structure the linear and non-linear properties of various materials leads thus to consider femtosecond laser as a fantastic tool. However, a deeper understanding of the light-matter interaction, with emphasis on multiphotons processes, is profoundly needed for the development of new optical devices based on nanoparticules mastering. This proposal is thus dedicated to 1/ to understand the processes of the formation of metallic nanostructures in glassy media and 2/ to manipulate, to master the nanocluster shape and mostly distribution within the dielectric matrix. This will allow structuring the non-linear properties in the dielectric matrix on demand.
East China University of Science and Technology | Date: 2010-12-09
Nitromethylene analogues of imidacloprid and divalent and oxabridged heterocyclic neonicotinoid compounds constructed by dialdehydes, preparation methods and uses thereof are disclosed. Compounds represented by formula (A) or (B), their optical isomers or agrochemically acceptable salts are provided. Agrochemical compositions comprising the said compounds, their optical isomers or agrochemically acceptable salts, the uses of the said agrochemical compositions and the preparation methods of the said compounds, their optical isomers or agrochemically acceptable salts are also disclosed. The compounds and their derivatives have high insecticidal activities to several farming and forestry pests including homoptera and lepidoptera pests, such as
East China University of Science and Technology | Date: 2013-12-05
Disclosed is the use of a fusion protein in drugs for stimulating differentiation of bone marrow mesenchymal stem cells to hematopoietic stem/progenitor cells, or drugs for proliferation of granulocyte hematopoietic progenitor cells. The fusion protein has a sequence as shown in SEQ ID NO: 2 or SEQ ID NO: 4. The drugs can be used for the prevention and/or treatment of (i) hematopoietic dysfunction caused by chemotherapy, (ii) hematopoietic dysfunction caused by radiotherapy, or (iii) leukopenia.
East China University of Science and Technology | Date: 2012-01-19
Methods of forming a liquid crystal blue phase from composite materials comprising a chiral nematic liquid crystal host and an azobenzene-based bent-shape molecule are described. The composite materials quickly transfer from the liquid crystal blue phase to an isotropic phase under electromagnetic radiation and transfer from the isotropic phase to the liquid crystal blue phase when electromagnetic radiation is removed.
Nicotinamide Adenine Dinucleotide Gene Encoding Fluorescent Probe, Preparation Method Therefor And Application Thereof
East China University of Science and Technology | Date: 2012-09-26
The invention relates to a genetically encoded fluorescent sensor for nicotinamide adenine dinucleotide, as well as methods of preparation and uses thereof. In one aspect, this invention relates to a sensor for detecting nicotinamide adenine dinucleotide, particularly, a recombinant fluorescent fusion protein sensor for detecting nicotinamide adenine dinucleotide. In one specific aspect, this invention relates to a recombinant fluorescent fusion protein sensor for detecting reduced nicotinamide adenine dinucleotide (NADH); in another specific aspect, this invention relates to a recombinant fluorescent fusion protein sensor for detecting oxidized nicotinamide adenine dinucleotide (NAD
Convective cooling/heating induced thermal stresses in a fluid saturated porous medium undergoing local thermal non-equilibrium
He L.-W.,East China University of Science and Technology |
Jin Z.-H.,University of Maine, United States |
Zhang Y.,East China University of Science and Technology
International Journal of Solids and Structures | Year: 2012
Local thermal non-equilibrium (LTNE) may have profound effects on the pore pressure and thermal stresses in fluid saturated porous media under transient thermal loads. This work investigates the temperature, pore pressure, and thermal stress distributions in a porous medium subjected to convective cooling/heating on its boundary. The LTNE thermo-poroelasticity equations are solved by means of Laplace transform for two fundamental problems in petroleum engineering and nuclear waste storage applications, i.e.; an infinite porous medium containing a cylindrical hole or a spherical cavity subjected to symmetrical thermo-mechanical loads on the cavity boundary. Numerical examples are presented to examine the effects of LTNE under convective cooling/heating conditions on the temperature, pore pressure and thermal stresses around the cavities. The results show that the LTNE effects become more pronounced when the convective heat transfer boundary conditions are employed. For the cylindrical hole problem of a sandstone formation, the thermally induced pore pressure and the magnitude of thermal stresses are significantly higher than the corresponding values in the classical poroelasticity, which is particularly true under convective cooling with moderate Biot numbers. For the spherical cavity problem of a clay medium, the LTNE effect may become significant depending on the boundary conditions employed in the classical theory. © 2011 Elsevier Ltd. All rights reserved. Source
Wang X.,East China University of Science and Technology |
Schiavone P.,University of Alberta
International Journal of Solids and Structures | Year: 2012
A novel method is proposed to design neutral N-phase (N ≥ 3) elliptical inclusions with internal uniform hydrostatic stresses. We focus on the study of the internal and external stress states of an N-phase elliptical inclusion which is bonded to an infinite matrix through (N - 2) interphase layers. The interfaces of the N-phase elliptical inclusion are (N - 1) confocal ellipses. The design of the resulting overall composite material consists of four stages: (i) an inner perfectly bonded interphase/inclusion interface which is necessary to make the internal uniform stress state hydrostatic; (ii) outer imperfect interphase layers properly designed to make the coated inclusion harmonic (i.e.; the uniform mean stress of the original field within the matrix is unperturbed); (iii) the aspect ratio of the elliptic inclusion uniquely chosen for a given material and thickness parameters to make the resulting coated inclusion neutral (i.e.; the prescribed uniform stress field in the matrix remains undisturbed); and finally (iv) the derivation of a simple condition relating the remote uniform stresses and the thickness parameters of the (N - 2) interphase layers for given material parameters which lead to internal uniform hydrostatic stresses. We note that another interesting feature of the present results is that the mean stress is found to be constant within each interphase layer, and the hoop stress in the innermost interphase layer is uniform along the entire interphase/inclusion interface. © 2011 Elsevier Ltd. All rights reserved. Source
Zou Q.,East China University of Science and Technology |
Tian H.,East China University of Science and Technology
Sensors and Actuators, B: Chemical | Year: 2010
Two novel 2,1,3-benzothiadiazole-based chemodosimeters (1a and 1b) were designed and synthesized, and their fluorescent behaviors toward various metal ions were investigated. Chemodosimeter 1a shows excellent optical properties and exclusively distinguishes Hg2+ and CH3Hg+ from other metal ions in aqueous solutions. Though the response of chemodosimeter 1b to Hg2+ and CH3Hg+ is slower than 1a, fortunately, chemodosimeter 1b becomes a promising fluorescent sensor for Hg2+ and CH3Hg+ with high selectivity. Evidences for the desulfurization mechanism were provided by UV-vis and fluorescence titration spectra and especially 1H NMR and HRMS experiments. © 2010 Elsevier B.V. All rights reserved. Source
Li F.,East China University of Science and Technology |
Lu X.,East China University of Science and Technology
Neural Networks | Year: 2013
This letter studies complete synchronization of two temporal Boolean networks coupled in the drive-response configuration. Necessary and sufficient conditions are provided based on the algebraic representation of Boolean networks. Moreover, the upper bound to check the criterion is given. Finally, an illustrative example shows the efficiency of the proposed results. © 2013 Elsevier Ltd. Source
An adaptive human-machine control system based on multiple fuzzy predictive models of operator functional state
Yang S.,East China University of Science and Technology |
Zhang J.,East China University of Science and Technology
Biomedical Signal Processing and Control | Year: 2013
Under the framework of adaptive Human-Machine (HM) systems, it has been proposed that human operators' task level should be dynamically adjusted according to his/her functional state. The construction of models that can reliably predict the operator functional state (OFS) becomes critical to accomplish such adjustments. However, most of the existing models that evaluate the current OFS by using operators' current physiological data are static and are of no real predictive capability. Thus, when they are used in adaptive HM systems, the resultant task allocation between operators and machines would be time-delayed. To overcome this problem, a one-step-ahead predictive model concept for OFS computation is proposed. Meanwhile, multiple fuzzy models are developed by using the Wang-Mendel method. These models are able to increase the accuracy of the OFS breakdown prediction, as well as to reduce the model training time. In addition, an adaptive task allocation strategy is designed to validate the proposed models. The results demonstrate that, compared to the conventional HM systems, a 6.7% OFS increment and a 57.1% OFS breakdown decrement can be obtained in the multiple models based adaptive HM systems. The multiple predictive models and the adaptive task allocation strategy would pave the way for future implementations of real-time adaptive HM systems. © 2012 Elsevier Ltd. All rights reserved. Source
Development of asymmetric phosphine-promoted annulations of allenes with electron-deficient olefins and imines
Zhao Q.-Y.,East China University of Science and Technology |
Lian Z.,CAS Shanghai Institute of Organic Chemistry |
Wei Y.,CAS Shanghai Institute of Organic Chemistry |
Shi M.,East China University of Science and Technology |
Shi M.,CAS Shanghai Institute of Organic Chemistry
Chemical Communications | Year: 2012
Asymmetric annulation of allenes with electron-deficient olefins and imines is one of the most important reactions for the synthesis of optically active carbo- and heterocycles, which are useful building blocks for the synthesis of natural products and medicinally important substances. The use of chiral phosphines as enantioselective catalysts can be envisaged for such cyclizations. This article focuses on the important developments concerning asymmetric annulations of allenes with unsaturated partners in the recent decades and on the perspectives that these new developments offer. © 2012 The Royal Society of Chemistry. Source
Benzoic Acid Catalyzed Annulations of α-Amino Acids and Aromatic Aldehydes Containing an ortho-Michael Acceptor: Access to 2,5-Dihydro-1H-benzo[c]azepines and 10,11-Dihydro-5H-benzo[e]pyrrolo[1,2-a]azepines
Yu X.,East China University of Science and Technology
Organic Letters | Year: 2015
A novel one-pot efficient synthesis of 2,5-dihydro-1H-benzo[c]azepines and 10,11-dihydro-5H-benzo[e]pyrrolo[1,2-a]azepines from α-amino acids and aromatic aldehydes containing an ortho-Michael acceptor is reported via decarboxylative annulations without metal catalysts in yields of 52-91%. Under microwave irradiation, this protocol provides rapid access to polycyclic ring systems (only 5 min in most cases). © 2015 American Chemical Society. Source
Analytical discussion on strong gravitational lensing for a massive source with a f (R) global monopole
Man J.,East China University of Science and Technology |
Cheng H.,East China University of Science and Technology
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015
Here we investigate the gravitational lensing in the strong field limit of a Schwarzschild black hole with a solid deficit angle owing to a global monopole within the context of the f(R) gravity theory. We obtain the expressions of the deflection angle and time delay in the forms of elliptic integrals and discuss the asymptotic behavior of the elliptic integrals to find the explicit formulas of the angle and time difference in the strong field limit. We show that the deflection angle and the time delay between multiple images are related not only to the monopole but also to the f(R) correction ψ0 by taking the cosmological boundary into account. Some observables such as the minimum impact parameter, the angular separation, the relative magnification, and the compacted angular position are estimated as well. It is intriguing that a tiny modification on standard general relativity will make a remarkable deviation on the angle and the time lag, offering a significant way to explore some possible distinct signatures of the topological soliton and the correction of Einstein's general relativity. © 2015 American Physical Society. Source
Tao J.,University of South Florida |
Cuan Q.,East China University of Science and Technology |
Gong X.-Q.,East China University of Science and Technology |
Batzill M.,University of South Florida
Journal of Physical Chemistry C | Year: 2012
Hydrogen adsorption and reaction on the rutile TiO 2(011)- 2×1 has been investigated by a combination of high-resolution scanning tunneling microscopy and density functional theory calculations. Hydroxyl formation on the reconstructed surface is weak, and hydroxyls have only been observed on one of the three different surface oxygen sites. Recombination of hydrogen and desorption of H 2 is prevented by a large kinetic barrier. Instead, hydrogen is removed from the surface at elevated temperature by diffusion into the bulk. This is contrasted with photoinduced processes investigated by UV-irradiation under ultra high vacuum conditions, which leads to desorption of hydrogen from the surface, indicating a photoinduced lowering of the reaction barrier. Our studies are also compared to previous studies on the rutile TiO 2(110) surface where different thermal and photoinduced processes have been reported. These differences are explained by three competing reaction pathways: (i) bulk diffusion, (ii) H 2 recombination, and (iii) water formation at the surface by lattice oxygen abstraction. The dependence of the reaction on the hydrogen-adsorption energies as well as on kinetic diffusion and reaction barriers and pathways can explain the observed differences between these two surface orientations. © 2012 American Chemical Society. Source
Zn2+-triggered amide tautomerization produces a highly Zn 2+-selective, cell-permeable, and ratiometric fluorescent sensor
Xu Z.,Ewha Womans University |
Xu Z.,University of Cambridge |
Baek K.-H.,Yonsei University |
Kim H.N.,Ewha Womans University |
And 5 more authors.
Journal of the American Chemical Society | Year: 2010
It is still a significant challenge to develop a Zn2+-selective fluorescent sensor with the ability to exclude the interference of some heavy and transition metal (HTM) ions such as Fe2+, Co2+, Ni2+, Cu2+, Cd2+, and Hg2+. Herein, we report a novel amide-containing receptor for Zn2+, combined with a naphthalimide fluorophore, termed ZTRS. The fluorescence, absorption detection, NMR, and IR studies indicated that ZTRS bound Zn2+ in an imidic acid tautomeric form of the amide/di-2-picolylamine receptor in aqueous solution, while most other HTM ions were bound to the sensor in an amide tautomeric form. Due to this differential binding mode, ZTRS showed excellent selectivity for Zn2+ over most competitive HTM ions with an enhanced fluorescence (22-fold) as well as a red-shift in emission from 483 to 514 nm. Interestingly, the ZTRS/Cd2+ complex showed an enhanced (21-fold) blue-shift in emission from 483 to 446 nm. Therefore, ZTRS discriminated in vitro and in vivo Zn2+ and Cd2+ with green and blue fluorescence, respectively. Due to the stronger affinity, Zn2+ could be ratiometrically detected in vitro and in vivo with a large emission wavelength shift from 446 to 514 nm via a Cd2+ displacement approach. ZTRS was also successfully used to image intracellular Zn2+ ions in the presence of iron ions. Finally, we applied ZTRS to detect zinc ions during the development of living zebrafish embryos. © 2010 American Chemical Society. Source
Jia Y.-F.,East China University of Science and Technology |
Xuan F.-Z.,East China University of Science and Technology
Wear | Year: 2012
In-situ nanoscratch experiments were carried out on occlusal surface and axial section (on which axis is perpendicular to rods and axis parallels to rods, respectively) of human enamel using a sphero-conical indenter (~1 μm tip radius) at different normal loads. The elastic recovery and inelastic deformation during scratching process was evaluated in terms of three curves along the track: surface roughness, scratch depth, and post depth. Coefficient of friction (COF) and wear rate was addressed for the single rod. Results reveal that the amount of elastic recovery and inelastic deformation of a single rod on the axial section is more than that on the occlusal surface. At the enamel rod scale, COF depends on loads and locations. The wear resistance of a single rod on the occlusal surface is greater than that at direction of axis perpendicular to rods and axis parallel to rods. The load-dependence is attributed to the ploughing and pile-up. The location-dependence is ascribed to the angle change of normal loading direction, hydroxyapatite crystals orientation and the scratching direction. In addition, viscoelastic protein layers between the apatite crystals play an important role in the anisotropic wear behavior at microscale. © 2012 Elsevier B.V. Source
Sih G.C.,Lehigh University |
Sih G.C.,East China University of Science and Technology
Theoretical and Applied Fracture Mechanics | Year: 2012
Uniaxial test data stand as monoscale average material property. They are unable of making connection with those at the microscopic scale. This impasse can be circumvented by using the surface energy density (SED) to establish a scale shifting law advocating the relation between the volume energy density (VED) and the length or size parameter for non-homogeneous systems. The homogeneous system corresponds to a perfect hyperbola when referred to the segmented scale of measurement standard of the Système international d'unités or simply the SI system.Scale segmentation is the lesser of two evils that avoids addressing the inconceivable limits of infinity. Dualscaling forms the basis for constructing multiscale systems. Invariancy of SED yields the scaling shifting law between the VED and the rate change of volume with surface, a length parameter. Evaluation of the sustainable and stable time of material microstructure can thus be made possible in segments and connected for a description of the evolutionary changes. The process corresponds to extending from the present into the past and future, regardless of the beginning and ending. © 2013 Elsevier Ltd. Source
Schizophrenia literacy among Chinese in Shanghai, China: A comparison with Chinese-speaking Australians in Melbourne and Chinese in Hong Kong
Wong D.F.K.,City University of Hong Kong |
He X.,East China University of Science and Technology
Australian and New Zealand Journal of Psychiatry | Year: 2011
Objective: The study reported in this paper was aimed at developing understanding of schizophrenia-related knowledge and preferences surrounding professional help, medication, and treatment methods among Chinese living in Shanghai, China. Method: A multi-stage cluster sampling method in which participants were taken from six of the 20 districts in Shanghai was adopted for this study. The 522 Shanghai Chinese participants were presented with a vignette describing an individual with schizophrenia before being asked questions designed to assess both their understanding of schizophrenia and their preferences surrounding professional help, medication, and treatment methods. A comparative approach was adopted to identify similarities and differences between our findings and those of two previous studies on the mental health literacy of Chinese living in Melbourne, Australia and Hong Kong, respectively. Results: A lower percentage of Shanghai Chinese than Hong Kong Chinese and Australian Chinese could correctly identify the condition described in the vignette as a case of acute schizophrenia. Although a far lower percentage of Shanghai Chinese endorsed the use of counselling professionals, a much higher percentage of the same group endorsed Chinese medical doctors and herbal medication. A lower percentage of Shanghai Chinese endorsed 'lifestyle changes' as a strategy for dealing with schizophrenia than did Chinese subjects living in Australia and Hong Kong. On the other hand, a higher percentage of Shanghai residents endorsed psychiatric treatment and the traditional Chinese practices of 'eating nutritious food/taking supplements' than among the other two groups of Chinese. Conclusions: This study highlights the need for educating Chinese in Shanghai to improve their schizophrenia literacy. The contents of the education programmes will need to take into consideration the socially and culturally driven beliefs that may have been influencing the knowledge and preferences of Shanghai Chinese concerning professional help, medication, and treatment methods for people suffering from schizophrenia. © 2011 The Royal Australian and New Zealand College of Psychiatrists. Source
Wang X.,East China University of Science and Technology
International Journal of Advanced Manufacturing Technology | Year: 2015
In gas tungsten arc welding (GTAW), the weld pool is the major source of information that can be used to assure the production of the desired weld penetration—the most critical factor determining the weld integrity. To meet this challenge, various sensing technologies, modeling methods, and control strategies have been studied, and artificial intelligence technologies were applied to improve system intelligence. The GTAW process analysis is given first. Then, a short introduction on weld pool sensing technologies is presented, where three-dimensional (3D) vision sensing is a very active orientation. Furthermore, weld pool description model and characteristic parameter model are also discussed, where intelligent algorithms were used generally. Besides, dynamic modeling and penetration control strategies, especially intelligent control strategies are presented. At last, the discussion about development of the GTAW penetration control product is analyzed briefly. © 2015 Springer-Verlag London Source
Palladium-catalyzed asymmetric 1,4-addition of diarylphosphines to nitroalkenes for the synthesis of chiral P,N-compounds
Feng J.-J.,East China University of Science and Technology |
Huang M.,East China University of Science and Technology |
Lin Z.-Q.,CAS Shanghai Institute of Organic Chemistry |
Duan W.-L.,CAS Shanghai Institute of Organic Chemistry
Advanced Synthesis and Catalysis | Year: 2012
A highly stereoselective asymmetric 1,4-addition of diarylphosphines to nitroalkenes catalyzed by a bis(phosphine) pincer-palladium complex has been developed for the synthesis of chiral P,N compounds with good to excellent enantioselectivities (up to 94% ee) under mild conditions. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Tian B.,East China University of Science and Technology |
Zhang J.,East China University of Science and Technology
Catalysis Surveys from Asia | Year: 2012
Semiconductor photocatalysis is considered to be one of the most promising technologies to solve the worldwide environmental and energy issues. In recent years, silver halide (AgX)-based photocatalytic materials have received increasing research attention owing to its excellent visible light-driven photocatalytic performances in the applications of organic pollutant degradation, H 2/O 2 generation, and disinfection. AgX-based materials used in photocatalytic fields can be classified into three categories: AgX (Ag/AgX), AgX composites, and supported AgX materials. For the AgX (Ag/AgX) photocatalysts, it has been widely accepted that the final photocatalytic performances of photocatalysts are severely dependent on their morphological structures as well as exposed crystal facets. As a result, considerable efforts have been devoted to fabricating different morphological AgX photocatalysts as well as exploring the relationship between the morphological structures and photocatalytic performances. In this review, we mainly introduce the recent developments made in fabricating morphology and facet-controllable AgX (Ag/AgX) photocatalytic materials. Moreover, this review also deals with the photocatalytic mechanism and applications of AgX (Ag/AgX) and supported AgX materials. © 2012 Springer Science+Business Media, LLC. Source
Wang X.,East China University of Science and Technology |
Schiavone P.,University of Alberta
European Journal of Mechanics, A/Solids | Year: 2012
We study the neutrality of circular inclusions with single or multiple coatings in the context of finite plane elasticity. All the phases in the composite belong to a particular class of compressible hyperelastic solids of harmonic-type. For an N-phase structure, at most 2 N different remote uniform hydrostatic loading states can be found for which the stress field in the surrounding matrix is the same as for a matrix containing no inclusions. For a three-phase structure, in which the asymptotic behavior of the harmonic materials obeys a constitutive restriction proposed by Knowles and Sternberg (1975) and the material parameter β is constant, we identify a critical value of the coating thickness parameter, above which the coated inclusion is neutral with respect to four different hydrostatic loading states, and at or below which the coated inclusion is neutral to only two different hydrostatic loading states. © 2011 Elsevier Masson SAS. All rights reserved. Source
Correlation between microstructure, hardness and strength in HAZ of dissimilar welds of rotor steels
Zhu M.-L.,East China University of Science and Technology |
Xuan F.-Z.,East China University of Science and Technology
Materials Science and Engineering A | Year: 2010
Correlation between microstructure, hardness and strength was investigated in heat affected zone (HAZ) of dissimilar welding joints of newly developed rotor steels in terms of both the traditional micro-hardness testing and the nanoindentation technique. Relationships between micro-hardness and nano-hardness were obtained for HAZ of welds, where the mechanical properties were microstructure dependent. Lath width of the tempered martensites was selected as the characteristic microstructure size for correlating the micro-hardness. The detailed strength distribution in HAZ and the correlation with the characteristic microstructure size were discussed. A good agreement was observed for the correlated strength and the experimental results in both weld metal (WM) and base metal (BM), and therefore gave us confidence for the application of the proposed relationship between the hardness and the mechanical properties in HAZ of the dissimilar weld. © 2010 Elsevier B.V. Source