Shanghai, China

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.


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Patent
East China University of Science and Technology | Date: 2014-04-23

Methods and systems for producing isosorbide from biomass are disclosed. In one embodiment, a method of producing isosorbide from biomass may include contacting biomass, a catalyst mixture of a noble metal and a first solid acid, and hydrogen to form a first reaction mixture, and heating the first reaction mixture to form at least one intermediate compound. Further, the intermediate compound is contacted with a second solid acid to form a second reaction mixture, and heating the second reaction mixture to form isosorbide.


Patent
East China University of Science and Technology | Date: 2014-05-14

Catalysts and methods for making cyclic carbonates are disclosed. The catalyst may include at least one polymer quaternary ammonium salt, at least one metal halide and silica gel. The method of making the cyclic carbonates may include forming a mixture that includes the catalyst and an epoxide, and contacting the mixture with carbon dioxide in a reactor under conditions to form the propylene carbonate.


Patent
East China University of Science and Technology | Date: 2014-07-21

The present invention relates to a method and a device for deep oil removal from wastewater containing a low concentration of wasteoil. Wastewater containing a low concentration of wasteoil enters the device via an inlet and passes through a flow conditioner, causing the fluid to become uniformly distributed. Then, by means of a layer of oleophilic-hydrophobic fibers and hydrophilic-oleophobic fibers woven in a certain manner, a trace of oil droplets are captured and then coalesce and grow on the layer, and a trace of oil-in-water emulsion is demulsified and separated on the layer. Finally, by means of corrugation-enhanced sedimentation and separation, the oil droplets coalesce and grow and are then separated rapidly. The invention also provides a set of devices for implementing the method, having several parts such as a housing, a feed pipe, a flow conditioner, a fiber coalescence layer, a corrugation-enhanced separation layer, and a level gauge. The present technique is highly efficient in separation, consumes little power, and can operate continuously for a long period of time. Thus, this technique can be widely used in processes for treating wastewater containing a low concentration of wasteoil.


Li Y.,East China University of Science and Technology | Xiao Y.,Queensland University of Technology | Liu C.,East China University of Science and Technology
Chemical Reviews | Year: 2017

Although the biological functions of cell and tissue can be regulated by biochemical factors (e.g., growth factors, hormones), the biophysical effects of materials on the regulation of biological activity are receiving more attention. In this Review, we systematically summarize the recent progress on how biomaterials with controllable properties (e.g., compositional/degradable dynamics, mechanical properties, 2D topography, and 3D geometry) can regulate cell behaviors (e.g., cell adhesion, spreading, proliferation, cell alignment, and the differentiation or self-maintenance of stem cells) and tissue/organ functions. How the biophysical features of materials influence tissue/organ regeneration have been elucidated. Current challenges and a perspective on the development of novel materials that can modulate specific biological functions are discussed. The interdependent relationship between biomaterials and biology leads us to propose the concept of “materiobiology”, which is a scientific discipline that studies the biological effects of the properties of biomaterials on biological functions at cell, tissue, organ, and the whole organism levels. This Review highlights that it is more important to develop ECM-mimicking biomaterials having a self-regenerative capacity to stimulate tissue regeneration, instead of attempting to recreate the complexity of living tissues or tissue constructs ex vivo. The principles of materiobiology may benefit the development of novel biomaterials providing combinative bioactive cues to activate the migration of stem cells from endogenous reservoirs (i.e., cell niches), stimulate robust and scalable self-healing mechanisms, and unlock the body’s innate powers of regeneration. © 2017 American Chemical Society.


Shi B.,East China University of Science and Technology | Gu X.,Fudan University | Fei Q.,East China University of Science and Technology | Zhao C.,East China University of Science and Technology
Chemical Science | Year: 2017

H2S is a key chemical mediator that exerts a vital role in diverse physiological and pathological processes. However, in vivo tracking of endogenous H2S generation still remains difficult due to the lack of reliable analytical methods. Herein, we present the first example of activatable photoacoustic probes for real-time imaging of H2S in living mice through the full utilization of the superiority of photoacoustic imaging modality at fine spatial resolution during deep tissue penetration. The designed probe can generate high NIR absorption at 780 nm in the presence of H2S, thus producing a strong photoacoustic signal output in the NIR region. Furthermore, this probe exhibits extremely fast and highly selective responsiveness, good water-solubility and excellent biocompatibility. In light of these outstanding features, this probe realizes the direct photoacoustic trapping of endogenous H2S generation in a HCT116 tumor-bearing mouse model. These preliminary imaging studies show that HCT116 colon tumors exhibit CBS upregulation activity, resulting in an increased rate of H2S generation. © The Royal Society of Chemistry.


Sun S.,University of Konstanz | Sun S.,East China University of Science and Technology | Gebauer D.,University of Konstanz | Colfen H.,University of Konstanz
Chemical Science | Year: 2017

While nature exerts precise control over the size and chemical composition of minerals, this is still a challenging task for artificial syntheses. Despite its significance, until now, there are still no reports on colloidal mineral nanoparticles in the subnanometer range. Here we developed a general gas diffusion strategy using 10,12-pentacosadiynoic acid as a ligand and ethanol as a solvent to fabricate stable amorphous mineral clusters with a core size of less than 2 nm. First discovered for CaCO3, the method was successfully extended to produce monolayer protected clusters of MgCO3, SrCO3, Eu2(CO3)3, Tb2(CO3)3, Ce2(CO3)3, Cax(PO4)y, CaC2O4 and their hybrid minerals, CaxMgy(CO3)z and Cax(CO3)y(PO4)z. All the mineral clusters can be well dispersed in organic solvents like toluene, and are stable for a long period without further crystallization. Our work paves a way for the artificial synthesis of colloidal mineral clusters, which may have various uses in both fundamental research and industry. © The Royal Society of Chemistry.


Zong J.,East China University of Science and Technology | Zong J.,CSIRO | Yang X.,East China University of Science and Technology | Trinchi A.,CSIRO | And 6 more authors.
Biosensors and Bioelectronics | Year: 2014

Copper ion (Cu2+) and l-cysteine (l-Cys) detection is critically important since an abnormal level of Cu2+ or l-Cys is an indicator for many diseases. In this paper, we demonstrate an "off-on" approach for highly sensitive and selective detection of Cu2+ and l-Cys using carbon dots (CDs) as fluorescent probes. CDs were prepared by using mesoporous silica (MS) spheres as nanoreactors. The binding ability of CDs towards metal ions was examined by comparing the fluorescence intensities of CDs before and after the addition of the metal ions. The addition of Cu2+ cations leads to their absorption on the surface of CDs and the significant fluorescence quench of CDs (turn-off). The resulting in CDs-Cu2+ system was found to be sensitive to l-Cys. The addition of l-Cys not only serves to shelter the CDs effectively from being quenched, but also to reverse the quenching and restore the fluorescence (turn-on) due to its ability to remove Cu2+ from the surface of CDs. This method is facile, rapid, low cost, and environment-friendly. A detection limit as low as 2.3×10-8M for Cu2+ and 3.4×10-10M for l-Cys is obtained, which is promising for biological applications. © 2013 Elsevier B.V.


Xu Y.,East China University of Science and Technology | Wang X.,East China University of Science and Technology
Mechanics of Advanced Materials and Structures | Year: 2017

We analytically investigate the contribution of arbitrarily varied surface elasticity to the Saint-Venant torsion problem of a circular cylinder containing a radial crack. The varied surface elasticity is incorporated by using a modified version of the continuum-based surface/interface model of Gurtin and Murdoch. In our discussion, the surface shear modulus is assumed to be arbitrarily varied along the crack surfaces. Both internal and edge cracks are studied. By using Green's function method, the boundary value problem is reduced to the Cauchy singular integro-differential equation of first order, which can be numerically solved by using the Gauss–Chebyshev integration formula, the Chebyshev polynomials, and the collocation method. The torsion problem of a cylinder containing two symmetric collinear radial cracks of equal length with symmetrically varied surface elasticity is also solved by using a similar method. Our numerical results indicate that the variation of the surface elasticity exerts a significant influence on the strengths of the logarithmic stress singularity at the crack tips, the torsional rigidity, and the jump in warping function. © 2017 Taylor & Francis Group, LLC


Mao W.,East China University of Science and Technology | Xia L.,East China University of Science and Technology | Xie H.,East China University of Science and Technology
Angewandte Chemie - International Edition | Year: 2017

Antibiotic resistance has become a major challenge to public health worldwide. This crisis is further aggravated by the increasing emergence of bacterial resistance to carbapenems, typically considered as the antibiotics of last resort, which is mainly due to the production of carbapenem-hydrolyzing carbapenemases in bacteria. Herein, the carbapenem-based fluorogenic probe CB-1 with an unprecedented enamine–BODIPY switch is developed for the detection of carbapenemase activity. This reagent is remarkably specific towards carbapenemases over other prevalent β-lactamases. Furthermore, the efficient imaging of live clinically important carbapenemase-producing organisms (CPOs) with CB-1 demonstrates its potential for the rapid detection of antibiotic resistance and timely diagnosis of CPO infections. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim


Wang C.,East China University of Science and Technology | Wang X.,East China University of Science and Technology
Mechanics of Materials | Year: 2017

A mode III rate-dependent bridged crack with surface elasticity is studied. The surface elasticity on the crack faces is incorporated by using a version of the continuum-based surface/interface theory of Gurtin and Murdoch. The bridging force along the crack is proportional, in terms of the constant or variable bridging viscosity, to the time-rate of the crack opening displacement. The Green's function method is used to derive a complete and transient solution by reducing the boundary value problem to a Cauchy singular integro-differential equation which can be further changed into state-space equations by means of the collocation method. The state-space equations are solved by a rigorous analysis of the eigenmodes. Detailed numerical results are presented for eigenvalues, eigenfunctions, and the evolution of the bridging force, crack opening displacement and the strength of the logarithmic singularity at the crack tips. © 2017 Elsevier Ltd


Yue H.,East China University of Science and Technology | Xue L.,East China University of Science and Technology | Chen F.,East China University of Science and Technology
Applied Catalysis B: Environmental | Year: 2017

RuO2-TiO2/Ti electrode was prepared for the electrocatalytic removal of nitrite in this work. The influences of calcination temperatures on crystal phase and morphology of RuO2-TiO2 composite were explored by XRD and TEM. The formation of RuO2 epitaxial layers on the surface of TiO2 by calcination at 400 °C reduces the impedance (EIS test) and improves the electrocatalytic activity for RuO2-TiO2. The CV test shows that the electrochemically surface active sites increase along with the increase of RuO2 content from 0 to 2.0 wt%. The nitrite removal rate of 2.0 wt% RuO2-TiO2/Ti electrode is found ca. 6.7 and 2.5 times faster than those of 0.02 wt% and 0.1 wt% RuO2-TiO2/Ti electrodes, respectively. Oxidation of the active sites on the RuO2 results in an obvious activity decrease for RuO2/Ti and RuO2-TiO2/Ti electrodes in just 3 reaction cycles (30 min/cycle). By exchanging the anode and cathode after every cycle, the catalytic activity of corresponding 2.0 wt% RuO2-TiO2/Ti electrode remains almost unchanged after 50 cycles. Although the electrocatalytic service life of RuO2/Ti electrode is also greatly improved, its electrocatalytic activity decreases much after 50 cycles. The relatively longer service life of 2.0 wt% RuO2-TiO2/Ti electrode should own to the intensified interaction between the epitaxially spread RuO2 and TiO2, which stabilizes the chemical states of RuO2. The main product for the electrocatalytic removal of nitrite is nitrate by indirect oxidation, while a small amount of ammonium is also produced at the cathode. The as-produced ammonium will be oxidized into nitrogen molecule, which is released from the aqueous solution afterwards and contributes the decrease of the total content of N in the solution. © 2017 Elsevier B.V.


Niu D.,East China University of Science and Technology | Li Y.,East China University of Science and Technology | Shi J.,East China University of Science and Technology | Shi J.,CAS Shanghai Institute of Ceramics
Chemical Society Reviews | Year: 2017

As a member of the organic-inorganic hybrid family, silica/organosilica cross-linked block copolymer micelles are becoming increasingly attractive due to the combined features of excellent self-assembly properties of amphiphilic block copolymers and the high stability and the easy surface modification of silica/organosilica components. Compared to the traditional cross-linking route with organic components, the silica/organosilica cross-linking approach could offer more advantages, such as quick reaction under mild conditions, a much stronger barrier to the diffusion of both encapsulated small molecules and functional nanoparticles and the substantial improvement in the stability of the whole micelles against the ambient environment. In this tutorial review, we will focus on the recent developments in the design, synthesis and biomedical applications of silica/organosilica cross-linked block copolymer micelles based on the self-assembly of amphiphilic block copolymers and the hydrolysis and condensation of silanes in aqueous solution. First, we will summarize the synthesis of three typical kinds of silica/organosilica cross-linked block copolymer micelles based on the self-assembly of non-ionic polyethylene oxide (PEO)-based, cationic and anionic poly(acrylic acid) (PAA)-based block copolymer micelles. Then, a series of multifunctional silica/organosilica cross-linked block copolymer micelles by encapsulating various functional nanoparticles/molecules in the hydrophobic polymer cores or hydrophilic silica/organosilica cross-linked shells are introduced and their biomedical applications in controlled drug delivery, bio-imaging (magnetic resonance, fluorescence and multimodal imaging) and imaging-guided therapies (photothermal and high intensity focused ultrasound therapies) will be discussed. Finally, the challenges and prospects of silica/organosilica cross-linked micellar nanostructures and their biological applications are discussed and assessed. It is highly expected that the silica/organosilica cross-linked micelles may provide a new and promising kind of carrier system for enhanced bio-imaging and efficient cancer therapy. © 2017 The Royal Society of Chemistry.


Li K.,East China University of Science and Technology | Dawydiak C.A.,Massachusetts Institute of Technology
Soil Science Society of America Journal | Year: 2017

Syenite is mainly composed of potassium feldspar (Kfs), which is a structural K-bearing mineral in soil, typically considered as an insoluble K resource. In contrast to the slow dissolution process, the initial non-steady state stage usually gives a fast K+ release rate and quickly decreasing, which is closely related with surface reactions. This process in a flow reactor has not been fully understood with a kinetic model. Earlier research about albite found that ion exchange and surface cation desorption occur rapidly, which leads to experimental efforts of this work. The 140-mesh (105-mm ) and 325-mesh (44-mm) syenite leaching tests were performed under room temperature and pressure, using pH 1 and 3 diluted nitric acids, and flow rates from 0.01 to 1 mL min-1 in a packed-bed flow reactor. Inductively coupled plasma mass spectrometry was used to measure the ions' (K+, Na+, Al3+, Si4+, Ca2+, Fe3+, Ba2+) time-dependent concentrations simultaneously. The pH measurement was added to monitor the consumption of reactant H+, providing reactant information crucial for understanding the surface reactions. The two fast surface reactions previously observed with albite were also observed with Kfs during the non-steady state. The initial K+ release kinetics were different from H+ adsorption and other surface atoms detachment. The slow dissolution reaction and the influence of transport factors were also evaluated. A model has been built with two parts that include the fast reactions and the transport- dissolution terms, conforming to the first-order equation with a leachant pH correction factor and a parabolic diffusion equation. © Soil Science Society of America, 5585 Guilford Rd., Madison WI 53711 USA. All Rights reserved.


Nie C.-X.,East China University of Science and Technology
Physica A: Statistical Mechanics and its Applications | Year: 2017

In this paper, correlation dimension is applied to financial data analysis. We calculate the correlation dimensions of some real market data and find that the dimensions are significantly smaller than those of the simulation data based on geometric Brownian motion. Based on the analysis of the Chinese and US stock market data, the main results are as follows. First, by calculating three data sets for the Chinese and US market, we find that large market volatility leads to a significant decrease in the dimensions. Second, based on 5-min stock price data, we find that the Chinese market dimension is significantly larger than the US market; this shows a significant difference between the two markets for high frequency data. Third, we randomly extract stocks from a stock set and calculate the correlation dimensions, and find that the average value of these dimensions is close to the dimension of the original set. In addition, we analyse the intuitional meaning of the relevant dimensions used in this paper, which are directly related to the average degree of the financial threshold network. The dimension measures the speed of the average degree that varies with the threshold value. A smaller dimension means that the rate of change is slower. © 2017 Elsevier B.V.


Song J.,East China University of Science and Technology | Niu Y.,East China University of Science and Technology | Zou Y.,East China University of Science and Technology
IEEE Transactions on Automatic Control | Year: 2017

This technical note investigates the sliding mode control (SMC) design based on finite-time boundedness (FTB) for a class of nonlinear systems. A suitable SMC law is constructed to drive the state trajectories onto the specified sliding surface during a specified finite (possibly short) time interval. Besides, by introducing a partitioning strategy, the corresponding FTB over reaching phase and sliding motion phase are guaranteed, respectively. And then, the sufficient conditions are derived to ensure the FTB of the closed-loop systems over the whole finite-time interval. Finally, a simulation example is given to show the effectiveness of the proposed design method. © 2016 IEEE.


Wang X.,East China University of Science and Technology | Schiavone P.,University of Alberta
Mathematics and Mechanics of Solids | Year: 2017

In this paper we derive explicit expressions for the Green's functions in the case of an anisotropic elastic half-space and bimaterial subjected to a line force and a line dislocation. In contrast to previous studies in this area, our analysis includes the contributions of both anisotropic surface elasticity and surface van der Waals interaction forces. By means of the Stroh sextic formalism, analytical continuation and the state-space approach, the corresponding boundary value problem is reduced to a system of six (for a half-space) or 12 (for a bimaterial) coupled first-order differential equations. By employing the orthogonality relations among the corresponding eigenvectors, the coupled system of differential equations is further decoupled to six (for a half-space) or 12 (for a bimaterial) independent first-order differential equations. The latter is solved analytically using exponential integrals. In addition, we identify four and seven non-zero intrinsic material lengths for a half-space and a bimaterial, respectively, due entirely to the incorporation of the surface elasticity and surface van der Waal forces. We prove that these material lengths can be only either real and positive or complex conjugates with positive real parts. © SAGE Publications.


Li F.,East China University of Science and Technology | Tang Y.,East China University of Science and Technology
Automatica | Year: 2017

This paper studies the set stabilization of switched Boolean control networks, in which a feedback control design algorithm is presented by a constructive method. Necessary and sufficient conditions of the set stabilization of switched Boolean control networks under arbitrary switching signals are presented for the cases of the control input relying on switching signals or not, respectively. Furthermore, the corresponding switching-signal-independent and switching-signal-dependent controllers are provided for these two cases, respectively. It is shown that the condition of the switching-signal-dependent controller is less conservative than the one of the switching-signal-independent controller. Finally, examples are given to illustrate the effectiveness of the proposed results. © 2016 Elsevier Ltd


Wang Y.,East China University of Science and Technology | Wang R.,East China University of Science and Technology | Xu X.,East China University of Science and Technology
Neural Plasticity | Year: 2017

Electrical activity is the foundation of the neural system. Coding theories that describe neural electrical activity by the roles of action potential timing or frequency have been thoroughly studied. However, an alternative method to study coding questions is the energy method, which is more global and economical. In this study, we clearly defined and calculated neural energy supply and consumption based on the Hodgkin-Huxley model, during firing action potentials and subthreshold activities using ion-counting and power-integral model. Furthermore, we analyzed energy properties of each ion channel and found that, under the two circumstances, power synchronization of ion channels and energy utilization ratio have significant differences. This is particularly true of the energy utilization ratio, which can rise to above 100% during subthreshold activity, revealing an overdraft property of energy use. These findings demonstrate the distinct status of the energy properties during neuronal firings and subthreshold activities. Meanwhile, after introducing a synapse energy model, this research can be generalized to energy calculation of a neural network. This is potentially important for understanding the relationship between dynamical network activities and cognitive behaviors. © 2017 Yihong Wang et al.


Zhu C.,Shanghai Maritime University | Wang Z.,East China University of Science and Technology
Pattern Recognition Letters | Year: 2017

Imbalance problem occurs when negative class contains many more patterns than that of positive class. Since conventional Support Vector Machine (SVM) and Neural Networks (NN) have been proven not to effectively handle imbalanced data, some improved learning machines including Fuzzy SVM (FSVM) have been proposed. FSVM applies a fuzzy membership to each training pattern such that different patterns can give different contributions to the learning machine. However, how to evaluate fuzzy membership becomes the key point to FSVM. Moreover, these learning machines present disadvantages to process matrix patterns. In order to process matrix patterns and to tackle the imbalance problem, this paper proposes an entropy-based matrix learning machine for imbalanced data sets, adopting the Matrix-pattern-oriented Ho–Kashyap learning machine with regularization learning (MatMHKS) as the base classifier. The new leaning machine is named EMatMHKS and its contributions are: (1) proposing a new entropy-based fuzzy membership evaluation approach which enhances the importance of patterns, (2) guaranteeing the importance of positive patterns and get a more flexible decision surface. Experiments on real-world imbalanced data sets validate that EMatMHKS outperforms compared learning machines. © 2017 Elsevier B.V.


Gong J.G.,East China University of Science and Technology | Xuan F.Z.,East China University of Science and Technology
Journal of Pressure Vessel Technology, Transactions of the ASME | Year: 2017

Notch-related weakening and strengthening behavior under creep-fatigue conditions was studied in terms of the elastic-viscoplasticity finite-element method (FEM). A coupled damage analysis, i.e., the skeletal point method for creep damage evaluation coupled with the equivalent strain range method for fatigue damage, was employed in the notch effect evaluation. The results revealed that, under the short holding time condition, a weakening behavior was observed for the notch, while a strengthening effect was detected with the increase of holding time. The difference could be ascribed to the creep damage contribution in the holding stage. The influence of stress concentration factor (SCF), stress ratio, and the maximum stress was strongly dependent on the competition of creep and fatigue mechanism. © 2016 by ASME.


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.


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.


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.


Sun J.-R.,East China University of Science and Technology | Wu S.-Y.,National Chiao Tung University | Wu S.-Y.,National Center for Theoretical Science | Zhang H.-Q.,University of Lisbon
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2014

We study the optical conductivity in a (2 + 1)-dimensional non-relativistic field theory holographically dual to a (3 + 1)-dimensional charged Lifshitz black brane within the Einstein-Maxwell-dilaton theory. Surprisingly, we find that the optical AC conductivity satisfies the nontrivial (non-)power law scaling in the high frequency regime rather than approaching to a constant when the dynamical critical exponent z> 1, which is qualitatively similar to those in various disordered solids in condensed matter systems. Besides, this (non-)power law scaling behavior shows some universality, which is robust against the temperatures. We argue that the peculiar scaling behavior of AC conductivity may stem from the couplings of the dilaton field with the gauge fields and also the logarithmic behavior near the boundary in the Lifshitz spacetime. © 2014 The Authors.


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.


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.


Du H.,East China University of Science and Technology | Ge S.S.,National University of Singapore | Liu J.K.,Beihang University
IET Control Theory and Applications | Year: 2011

In this study, an output feedback-based adaptive neural controller is presented for a class of uncertain non-affine pure-feedback non-linear systems with unmodelled dynamics. Two major technical difficulties for this class of systems lie in: (i) the few choices of mathematical tools in handling the non-affine appearance of control in the systems, and (ii) the unknown control direction embedded in the unknown control gain functions, in great contrast to the standard assumptions of constants or bounded time-varying coefficients. By exploring the new properties of Nussbaum gain functions, stable adaptive neural network control is possible for this class of systems by using a strictly positive-realness-based filter design. The closed-loop system is proven to be semi-globally uniformly ultimately bounded, and the regulation error converges to a small neighbourhood of the origin. The effectiveness of the proposed design is verified by simulations. © 2011 The Institution of Engineering and Technology.


Zhang W.,East China University of Science and Technology | Jin C.,Shanghai University | Yang Y.,Shanghai University | Zhong X.,East China University of Science and Technology
Inorganic Chemistry | Year: 2012

Nearly all reported approaches for synthesis of high quality CdSe nanocrystals (NCs) involved two steps of preparation of Cd or Se stock solution in advance and then mixing the two reactants via hot-injection in high temperature. In this manuscript, Gram-scale CdSe multipod NCs were facilely synthesized in a noninjection route with the use of CdO and Se powder directly as reactants in paraffin reaction medium containing small amount of oleic acid and trioctylphosphine. The influence of various experimental variables, including reaction temperature, nature and amount of surfactants, Cd-to-Se ratio, and the nature of reactants, on the morphology of the obtained CdSe NCs have been systematically investigated. After deposition of ZnS shell around the CdSe multipod NCs, the PL QY of the obtained CdSe/ZnS can be up to 85%. The reported noninjection preparation approach can satisfy the requirement of industrial production bearing the advantage of low-cost, reproducible, and scalable. Furthermore, this facile noninjection strategy provides a versatile route to large-scale preparation of other semiconductor NCs with multipod or other morphologies. © 2011 American Chemical Society.


Chen Y.,East China University of Science and Technology | Chen Y.,Fudan University | Zhang B.,East China University of Science and Technology | Liu G.,National University of Singapore | And 2 more authors.
Chemical Society Reviews | Year: 2012

As the thinnest material ever known in the universe, graphene has been attracting tremendous amount of attention in both materials science and condensed-matter physics since its successful isolation a few years ago. This one-atom-thick two-dimensional pseudo-infinite nano-crystal consists of sp 2-hybridized aromatic carbon atoms covalently packed into a continuous hexagonal lattice. Graphene exhibits a range of unique properties, viz., high three-dimensional aspect ratio and large specific surface area, superior mechanical stiffness and flexibility, remarkable optical transmittance, extraordinary thermal response and excellent electronic transport properties, promising its applications in the next generation electronics. To switch graphene and its derivatives between ON and OFF states in nanoelectronic memory devices, various techniques have been developed to manipulate the carbon atomic sheets via introducing the valence-conduction bandgap and to enhance their processability. In this article, we review the utilization of electrically, thermally and chemically modified graphene and its polymer-functionalized derivatives for switching and information storage applications. The challenges posed on the development of novel graphene materials and further enhancements of the device switching performance have also been discussed. © 2012 The Royal Society of Chemistry.


Liao W.,East China University of Science and Technology | Liao W.,Peking University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2010

We study dark matter (DM) in the model with one keV scale right-handed neutrino νR1 and two GeV scale right-handed neutrinos νR2,3, the νSM. We find that one of the GeV scale right-handed neutrinos can have a much longer lifetime than the other when two GeV scale right-handed neutrinos are degenerate. We show that the mass and mixing of light neutrinos can be explained in this case. Significant entropy release can be generated in a reheating produced by the decay of one of the GeV scale νR. The density of νR1 DM can be diluted by 2 orders of magnitude, and the mixing of νR1 with active neutrinos is allowed to be much larger, reaching the bound from x-ray observation. This mixing can lead to a sizable rate of νR1 capture by radioactive nuclei. The νR1 capture events are mono-energetic electrons with keV scale energy away from the beta decay spectrum. This is a new way to detect DM in the Universe. © 2010 The American Physical Society.


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.


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.


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.


Song J.-M.,East China University of Science and Technology | Song J.-M.,Hefei University | Wei D.-Z.,East China University of Science and Technology
Biomass and Bioenergy | Year: 2010

Bagasse, the main coproduct in the sugar industry, has been shown to be the sole carbon source for liquid-state fermentation to produce hydrolytic enzymes (cellulases and xylanases) using Cellulosimicrobium cellulans in flask during 3 days and the enzymatic extracts obtained at different time intervals were analysed. The degradation of bagasse indicate the lignocellulolytic capacity of C. cellulans, 26% decrease in hemicellulose content at 96 h, while 10% decrease in cellulose. This accord to that xylanases fairly predominated over cellulases. A rapid rise in the activity of cellulases and xylanases was observed in the early stages of incubation (within the first 24 h). The optimum pH for these enzymes by C. cellulans in liquid cultures was between 5.0 and 5.6 and the optimum temperature was 50 °C. Thermal stability of the enzymes was appreciable up to 45 °C, pH stability at pH 5.0. © 2010 Elsevier Ltd.


Ning C.,East China University of Science and Technology | Su E.,Nanjing Forestry University | Wei D.,East China University of Science and Technology
Archives of Biochemistry and Biophysics | Year: 2014

Lodderomyces elongisporus LH703 isolated from soil samples contained three novel aldo-keto reductases (AKRs) (LEAKR 48, LEAKR 49, and LEAKR 50). The three enzymes were cloned, expressed, and purified to homogeneity for characterization. These three AKRs shared <40% amino acid identity with each other. LEAKR 50 was identified as a member of AKR3 family, whereas the other two LEAKRs were identified as members of two novel AKR families, respectively. All the three AKRs required nicotinamide adenine dinucleotide phosphate as a cofactor. However, they showed diverse characteristics, including optimum catalyzing conditions, resistance to adverse reaction conditions, and substrate specificity. LEAKR 50 was estimated to be a promising biocatalyst that could reduce ethyl 4-chloroacetoacetate with high enantiomeric excess (98% e. e.) and high activity residue under adverse conditions. © 2014 Elsevier Inc.


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.


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.


Huang K.,Peking University | Zhang J.,East China University of Science and Technology
Energy Procedia | Year: 2011

With the strategy of sustainable development is generally accepted, developed countries are harmonious developing oil and gas and ecological environment by developing circular economy and building cyclic ecological society. Circular economy has a successful practice in the oil and gas industry in some developed countries and has formed the varied and practicable development modes. In this paper, circular economy strategies of oil and gas exploitation in China have been analyzed. The author believes that would be helpful to "low extraction, high use and low emissions". © 2011 Published by Elsevier Ltd.


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.


Gui R.,East China University of Science and Technology | Gui R.,Shanghai JiaoTong University | An X.,East China University of Science and Technology
RSC Advances | Year: 2013

A layer-by-layer epitaxial method was developed to synthesize water-soluble, near-infrared (NIR)-emitting type-II core/shell CdTe/CdS quantum dots (QDs) via employing glutathione-capped CdTe QDs as core templates, CdCl2 and thiourea as shell precursors. CdTe/CdS type-II nanostructure yields the QDs with NIR emission by varying the size of CdTe cores and the thickness of CdS shells. Compared to CdTe core QDs, CdTe/CdS core/shell QDs exhibit remarkable red-shifted spectra, and the corresponding emission maximum wavelength can span from 626 to 809 nm. Surface passivation of ZnS shell with a substantially wide bandgap restrains the excitons within CdTe/CdS QDs interface and isolates them from aqueous solution. This passivation therefore improves the photoluminescence (PL) efficiency of the CdTe/CdS nanostructure, including PL quantum yield, lifetime and photo-stability/catalytic activity. Through comprehensive research on their core/shell nanostructures, the CdTe/CdS QDs obtained from hydrothermal shell-coating route, show good monodispersity, lattice-mismatched heterostructure and NIR-emission properties, offering a great potential for biological or biomedical applications. © The Royal Society of Chemistry 2013.


Huang C.,East China University of Science and Technology | Qian Z.-G.,Shanghai JiaoTong University | Zhong J.-J.,East China University of Science and Technology | Zhong J.-J.,Shanghai JiaoTong University
Journal of Biotechnology | Year: 2013

In this work, the effect of N,N'-dicyclohexylcarbodiimide (DCCD) on ginsenoside biosynthesis in suspension cultures of Panax ginseng cells was investigated. The optimal concentration and timing of DCCD addition were found to be 10. μM and on day 4 of cultivation. Under this condition, the maximal content of total ginsenosides increased to 3.0-fold that of untreated control, and the contents of Rg-group (Rg1 and Re) ginsenosides and Rb1 were 2.5- and 8.9-fold higher, respectively, which coincided with elevated activities of protopanaxatriol biosynthetic enzyme protopanaxadiol 6-hydroxylase and UDPG-ginsenoside Rd glucosyltransferase that converts Rd to Rb1. In addition, DCCD treatment induced the activity of defense response enzyme, phenylalanine ammonia lyase. To gain a better understanding of the molecular processes underlying the elicitation, we examined nitric oxide (NO) content and expression levels of the triterpene biosynthetic genes encoding squalene synthase (sqs), squalene epoxidase (se), and dammarenediol-II synthase (ds). It was found that DCCD up-regulated NO generation and transcription levels of sqs, se and ds. Interestingly, these effects of DCCD were compromised by an NO biosynthetic inhibitor, while an NO donor alone recapitulated the elicitation effect of DCCD on ginsenoside biosynthesis. These results suggest that DCCD may induce the ginsenoside biosynthesis via NO signaling in the P. ginseng cells. The information obtained might also be helpful to hyperproduction of valuable secondary metabolites in other plant cell cultures. © 2013 Elsevier B.V.


Pan Z.,East China University of Science and Technology | Mora-Sero I.,Jaume I University | Shen Q.,University of Electro - Communications | Shen Q.,Japan Science and Technology Agency | And 7 more authors.
Journal of the American Chemical Society | Year: 2014

Semiconductor quantum dots (QDs) are extremely interesting materials for the development of photovoltaic devices, but currently the present the drawback is that the most efficient devices have been prepared with toxic heavy metals of Cd or Pb. Solar cells based on "green" QDs-totally free of Cd or Pb-present a modest efficiency of 2.52%. Herein we achieve effective surface passivation of the ternary CuInS2 (CIS) QDs that provides high photovoltaic quality core/shell CIS/ZnS (CIS-Z) QDs, leading to the development of high-efficiency green QD solar cells that surpass the performance of those based on the toxic cadmium and lead chalcogenides QDs. Using wide absorption range QDs, CIS-Z-based quantum dot sensitized solar cell (QDSC) configuration with high QD loading and with the benefit of the recombination reduction with type-I core/shell structure, we boost the power conversion efficiency of Cd- and Pb-free QDSC to a record of 7.04% (with certified efficiency of 6.66%) under AM 1.5G one sun irradiation. This efficiency is the best performance to date for QDSCs and also demonstrates that it is possible to obtain comparable or even better photovoltaic performance from green CIS QDs to the toxic cadmium and lead chalcogenides QDs. © 2014 American Chemical Society.


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.


Ding L.,East China University of Science and Technology | Zhang Z.,East China University of Science and Technology | Li X.,KTH Royal Institute of Technology | Su J.,East China University of Science and Technology
Chemical Communications | Year: 2013

Two thioxanthone-based fluorescent probes exhibited prominent solvatofluorochromism, and they were further found to be useful as fluorescence indicators for the qualitative and quantitative detection of low-level water content in various solvent media. © 2013 The Royal Society of Chemistry.


Guo Z.,East China University of Science and Technology | Zhu W.,East China University of Science and Technology | Zhu M.,Shanghai JiaoTong University | Wu X.,East China University of Science and Technology | Tian H.,East China University of Science and Technology
Chemistry - A European Journal | Year: 2010

Three tricarbocyanine dyes (IR-897, IR-877, and IR-925) with different thiourea substituents that function as dosimeter units through specific Hg 2+-induced desulfurization have been demonstrated in a fast indicator paper for Hg2+ and MeHg+ ions. In comparison with available Hg2+-selective chemodosimeters, IR-897 and IR-877 show several advantages, such as convenient synthesis, very long wavelengths falling in the near-infrared (NIR) region (650-900nm) with high molar extinction coefficients, a ratiometric response, and quite low disturbance with Ag + and Cu2+ ions. They exhibit large redshifts, which result in a clear color change from deep blue to pea green that can be easily monitored by the naked eye for a convenient indicator paper. In emission spectra, they display a characteristic turn-off mode at 780nm and turn-on mode at 830nm with titration of Hg2+ ions. Remarkably, the signal/noise (S/N) ratio with other thiophilic metal ions (Ag+ and Cu 2+) is greatly enhanced with ratiometric measurement of two channels: excitation spectra mode (I810nm/I670nm, monitored at 830nm) and emission spectra mode (I830nm/I780nm, isosbestic absorption point at 730nm as excitation). The distinct response is dependent upon the electron-donating effect of the thiourea substituents; that is, the stronger the electron-donating capability of the thiourea substituents, the faster the Hg2+-promoted cyclization. Additionally, experiments with living SW1116 cells show that these three tricarbocyanine dyes with low toxicity can exhibit special characteristics that are favorable for visualizing intracellular Hg2+ and MeHg+ ions in biological systems, including excellent membrane permeability, minimal interfering absorption and fluorescence from biological samples, low scattering, and deep penetration into tissues. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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.


Yang L.,East China University of Science and Technology | Li X.,KTH Royal Institute of Technology | Yang J.,East China University of Science and Technology | Qu Y.,East China University of Science and Technology | Hua J.,East China University of Science and Technology
ACS Applied Materials and Interfaces | Year: 2013

Two new near-infrared chemodosimeters for cyanide anion based on 5,10-dihexyl-5,10-dihydrophenazine were designed and synthesized. With dicyano-vinyl groups as the recognition site and electron-withdrawing groups on both sides, probe 1 exhibited an intramolecular charge transfer (ICT) absorption band at 545 nm and emission band at 730 nm, respectively, and thus showed an ICT block process and realized an "on-off" response after bilateral reaction with cyanide anions in CH3CN. Probe 2 utilized an unreactive formyl group instead of one of the two reactive dicyano-vinyl groups as the electron-withdrawing component. Due to the unilateral recognition process the ICT of probe 2 was redirected and lead to a remarkably colorimetric and ratiometric near-infrared (NIR) fluorescent response for cyanine. Both probes provided high sensitivity and selectivity with apparent response signals which can be observed by naked eyes, even in the copresence of various other interference anions. Optical spectroscopic techniques, NMR titration measurements, and density functional theory calculations were conducted to rationalize the sensing mechanisms of these two probes. © 2013 American Chemical Society.


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.


Jiao S.,East China University of Science and Technology | Shen Q.,University of Electro - Communications | Shen Q.,Japan Science and Technology Agency | Mora-Sero I.,Jaume I University | And 7 more authors.
ACS Nano | Year: 2015

Even though previously reported CdTe/CdSe type-II core/shell QD sensitizers possess intrinsic superior optoelectronic properties (such as wide absorption range, fast charge separation, and slow charge recombination) in serving as light absorbers, the efficiency of the resultant solar cell is still limited by the relatively low photovoltage. To further enhance photovoltage and cell efficiency accordingly, ZnTe/CdSe type-II core/shell QDs with much larger conduction band (CB) offset in comparison with that of CdTe/CdSe (1.22 eV vs 0.27 eV) are adopted as sensitizers in the construction of quantum dot sensitized solar cells (QDSCs). The augment of band offset produces an increase of the charge accumulation across the QD/TiO2 interface under illumination and induces stronger dipole effects, therefore bringing forward an upward shift of the TiO2 CB edge after sensitization and resulting in enhancement of the photovoltage of the resultant cell devices. The variation of relative chemical capacitance, Cμ, between ZnTe/CdSe and reference CdTe/CdSe cells extracted from impedance spectroscopy (IS) characterization under dark and illumination conditions clearly demonstrates that, under light irradiation conditions, the sensitization of ZnTe/CdSe QDs upshifts the CB edge of TiO2 by the level of ∼50 mV related to that in the reference cell and results in the enhancement of Voc of the corresponding cell devices. In addition, charge extraction measurements have also confirmed the photovoltage enhancement in the ZnTe/CdSe cell related to reference CdTe/CdSe cell. Furthermore, transient grating (TG) measurements have revealed a faster electron injection rate for the ZnTe/CdSe-based QDSCs in comparison with the CdSe cells. The resultant ZnTe/CdSe QD-based QDSCs exhibit a champion power conversion efficiency of 7.17% and a certified efficiency of 6.82% under AM 1.5G full one sun illumination, which is, as far as we know, one of the highest efficiencies for liquid-junction QDSCs. © 2015 American Chemical Society.


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.


Zhang J.,Shanghai JiaoTong University | Yang H.,Shanghai JiaoTong University | Shen G.,Shanghai JiaoTong University | Cheng P.,Shanghai JiaoTong University | And 2 more authors.
Chemical Communications | Year: 2010

We demonstrated that the individual graphene oxide sheets can be readily reduced under a mild condition using l-ascorbic acid (l-AA). This simple approach should find practical applications in large scale production of water soluble graphene. © 2010 The Royal Society of Chemistry.


Yu J.-L.,East China University of Science and Technology | Xia X.-X.,Shanghai JiaoTong University | Zhong J.-J.,East China University of Science and Technology | Zhong J.-J.,Shanghai JiaoTong University | Qian Z.-G.,Shanghai JiaoTong University
Biotechnology and Bioengineering | Year: 2014

The C6 dicarboxylic acid, adipic acid, is an important platform chemical in industry. Biobased production of adipic acid is a promising alternative to the current petrochemical route. Here, we report biosynthesis of adipic acid using an artificial pathway inspired by the reversal of beta-oxidation of dicarboxylic acids. The biosynthetic pathway comprises condensation of acetyl-CoA and succinyl-CoA to form the C6 backbone and subsequent reduction, dehydration, hydrogenation, and release of adipic acid from its thioester. The pathway was first tested in vitro with reconstituted pathway enzymes and then functionally introduced into Escherichia coli for the biosynthesis and excretion of adipic acid into the culture medium. The production titer was increased by approximately 20-fold through the combination of recruiting enzymes that were more suitable to catalyze the synthetic reactions and increasing availability of the condensation substrates. This work demonstrates direct biosynthesis of adipic acid via non-natural synthetic pathway, which may enable its renewable production. Biotechnol. Bioeng. 2014;111: 2580-2586. © 2014 Wiley Periodicals, Inc.


Wang S.,East China University of Science and Technology | Chen K.,East China University of Science and Technology | Chen K.,Shanghai JiaoTong University | Li L.,East China University of Science and Technology | Guo X.,East China University of Science and Technology
Biomacromolecules | Year: 2013

Cationic spherical polyelectrolyte brushes (SPBs) were synthesized by photoemulsion polymerization, consisting of a polystyrene core with a diameter around 80 nm and a poly(2-aminoethylmethacrylate hydrochloride) (PAEMH) shell with a thickness from 10 to 50 nm densely grafted on the core surface. The binding of various proteins onto SPBs was observed by turbidimetric titration, dynamic light scattering (DLS), zeta potential, and isothermal titration calorimetry (ITC). The binding, aggregation, and releasing of proteins by SPB can be tuned by modulating pH. The pH regions of binding for bovine serum albumin (BSA), β-lactoglobulin (BLG), and papain onto SPBs are markedly different and tunable by ionic strength and stoichiometry between protein and SPB. Binding energetics, affinity, and amount of various proteins onto cationic SPBs were determined by ITC. These findings lay the foundation for SPB applications in the protein purification and selective immobilization of different proteins, enzymes, and antibodies. © 2013 American Chemical Society.


Yu Z.,East China University of Science and Technology | Li S.,Shanghai JiaoTong University | Du H.,East China University of Science and Technology
International Journal of Robust and Nonlinear Control | Year: 2013

This paper addresses the problem of adaptive neural control for a class of uncertain stochastic pure-feedback nonlinear systems with time-varying delays. Major technical difficulties for this class of systems lie in: (1) the unknown control direction embedded in the unknown control gain function; and (2) the unknown system functions with unknown time-varying delays. Based on a novel combination of the Razumikhin-Nussbaum lemma, the backstepping technique and the NN parameterization, an adaptive neural control scheme, which contains only one adaptive parameter is presented for this class of systems. All closed-loop signals are shown to be 4-Moment semi-globally uniformly ultimately bounded in a compact set, and the tracking error converges to a small neighborhood of the origin. Finally, two simulation examples are given to demonstrate the effectiveness of the proposed control schemes. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.


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.


Zhou X.,East China University of Science and Technology | Zhong J.-J.,East China University of Science and Technology | Zhong J.-J.,Shanghai JiaoTong University
Biotechnology and Bioengineering | Year: 2011

Intracellular signals are critical to secondary metabolite biosynthesis by plant cells, but their quantitative effects are not yet well understood in plant cell cultures. Using Taxus chinensis suspension culture, which has the potential to provide a sustainable supply of highly useful bioactive taxoids, this work investigated the impact of endogenous salicylic acid (SA) level on taxuyunnanine C (Tc) biosynthesis. It was observed that the Tc accumulation was strongly dependent on the endogenous SA level. Under elicitation with an endogenous SA of 97.1 ± 11.8 μg/g dry weight, a maximal Tc content of 10.3 ± 0.52 mg/g dry weight was obtained. The transcription levels of Tc biosynthetic genes of geranylgeranyl diphosphate synthase and taxadiene synthase were also analyzed, and they were increased with increase of internal SA level. The results demonstrated that manipulation of endogenous SA level could be an efficient strategy for improving secondary metabolite biosynthesis in plant cell culture. © 2010 Wiley Periodicals, Inc.


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.


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.


Zhang Y.,Shanghai JiaoTong University | Zhang J.,East China University of Science and Technology | Huang X.,East China University of Science and Technology | Zhou X.,Shanghai JiaoTong University | And 2 more authors.
Small | Year: 2012

Biochemical and biomedical applications of graphene oxide (GO) critically rely on the interaction of biomolecules with it. It has been previously reported that the biological activity of the GO-enzyme conjugate decreases due to electrostatic interaction between the enzymes and GO. Herein, the immobilization of horseradish peroxidase (HRP) and oxalate oxidase (OxOx) on chemically reduced graphene oxide (CRGO) are reported. The enzymes can be adsorbed onto CRGO directly with a tenfold higher enzyme loading than that on GO, and maximum enzyme loadings reach 1.3 and 12 mg mg -1 for HRP and OxOx, respectively. Significantly, the more CRGO is reduced, the higher the enzyme loading. The CRGO-HRP conjugates also exhibit higher enzyme activity and stability than GO-HRP. Excellent properties of the CRGO-enzyme conjugates are attributed to hydrophobic interaction between the enzymes and the CRGO. The hydrophobic interaction mode of the CRGO-enzyme conjugates can be applied to other hydrophobic proteins, and thus could dramatically improve the performance of immobilized proteins. The results indicate that CRGO is a potential substrate for efficient enzyme immobilization, and is an ideal candidate as a macromolecule carrier and biosensor. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhou X.,Shanghai JiaoTong University | Zhang Y.,Shanghai JiaoTong University | Wang C.,East China University of Science and Technology | Wu X.,Shanghai JiaoTong University | And 5 more authors.
ACS Nano | Year: 2012

Graphene quantum dots (GQDs) are great promising in various applications owing to the quantum confinement and edge effects in addition to their intrinsic properties of graphene, but the preparation of the GQDs in bulk scale is challenging. We demonstrated in this work that the micrometer sized graphene oxide (GO) sheets could react with Fenton reagent (Fe 2+/Fe 3+/H 2O 2) efficiently under an UV irradiation, and, as a result, the GQDs with periphery carboxylic groups could be generated with mass scale production. Through a variety of techniques including atomic force microscopy, X-ray photoelectron spectroscopy, gas chromatography, ultraperformance liquid chromatography-mass spectrometry, and total organic carbon measurement, the mechanism of the photo-Fenton reaction of GO was elucidated. The photo-Fenton reaction of GO was initiated at the carbon atoms connected with the oxygen containing groups, and C-C bonds were broken subsequently, therefore, the reaction rate depends strongly on the oxidization extent of the GO. Given the simple and efficient nature of the photo-Fenton reaction of GO, this method should provide a new strategy to prepare GQDs in mass scale. As a proof-of-concept experiment, the novel DNA cleavage system using as-generated GQDs was constructed. © 2012 American Chemical Society.


Chen X.,East China University of Science and Technology | Zhou X.,Shanghai JiaoTong University | Han T.,Shanghai JiaoTong University | Wu J.,East China University of Science and Technology | And 2 more authors.
ACS Nano | Year: 2013

DNA i-motif structures have been found in telomeric, centromeric DNA and many in the promoter region of oncogenes; thus they might be attractive targets for gene-regulation processes and anticancer therapeutics. We demonstrate in this work that i-motif structures can be stabilized by graphene quantum dots (GQDs) under acidic conditions, and more importantly GQDs can promote the formation of the i-motif structure under alkaline or physiological conditions. We illustrate that the GQDs stabilize the i-motif structure through end-stacking of the bases at its loop regions, thus reducing its solvent-accessible area. Under physiological or alkaline conditions, the end-stacking of GQDs on the unfolded structure shifts the equilibrium between the i-motif and unfolded structure toward the i-motif structure, thus promoting its formation. The possibility of fine-tuning the stability of the i-motif and inducing its formation would make GQDs useful in gene regulation and oligonucleotide-based therapeutics. © 2012 American Chemical Society.


Chen X.,University of Illinois at Urbana - Champaign | Chen X.,East China University of Science and Technology | Noh K.W.,University of Illinois at Urbana - Champaign | Wen J.G.,Argonne National Laboratory | Dillon S.J.,University of Illinois at Urbana - Champaign
Acta Materialia | Year: 2012

Electrodeposition and electropolishing of nanograined nickel has been observed using an in situ electrochemical wet cell developed for transmission electron microscopy. The cell employs two thin film nickel electrodes in a 0.1 M aqueous NiCl2 electrolyte, which were biased at ±1 V. Anisotropic electrodeposition was observed in which growth of the nickel film across the substrate occurred much more rapidly than growth perpendicular to the substrate. The anisotropic behavior results from relatively equiaxed nanograins nucleating at the growth front with little subsequent coarsening. Grains were observed to nucleate ahead of the growth front, suggesting a new mechanism for electrochemically driven growth across a substrate which depends on ionic surface adsorption ahead of the growth front. During electropolishing the dissolution of nickel tended to occur more isotropically. The film thinned relatively uniformly until certain regions displayed Rayleigh instabilities. At this point the film broke up and some regions coarsened rapidly and/or were subject to electromigration. © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.


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.


Feng Y.,East China University of Science and Technology | Tiao N.,Centers for Disease Control and Prevention | Li N.,East China University of Science and Technology | Hlavsa M.,Centers for Disease Control and Prevention | Xiao L.,Centers for Disease Control and Prevention
Journal of Clinical Microbiology | Year: 2014

The United States has experienced a substantial increase in the reported incidence of cryptosporidiosis since 2005. Accompanying this is the emergence of a new subtype of Cryptosporidium hominis based on variation at the 60-kDa glycoprotein (gp60) locus, IaA28R4, which has become a frequently identified subtype in both sporadic and outbreak-related cases. In this study, using multilocus sequence typing (MLST) at eight genetic loci, we characterized 62 specimens of IaA28R4 and 33 specimens of three other gp60 subtypes of C. hominis from four U.S. states with increased cryptosporidiosis incidences during the summer of 2008. Extensive genetic heterogeneity was seen within the gp60 subtype IaA28R4, but specimens from Ohio and southwestern states formed two distinct subpopulations, suggesting that there were at least two origins of IaA28R4 within the United States. Discordance in typing results was observed between gp60 and other genetic markers, especially DZ-HRGP, and this discordance was largely the result of genetic recombination within the gp60 subtype IaA28R4. The results of population genetic analyses supported the presence of two subpopulations of IaA28R4 and the occurrence of genetic recombination within this gp60 subtype. Thus, the IaA28R4 subtype at gp60 is likely a fitness marker for C. hominis, and genetic recombination is potentially a driving force in the emergence of the virulent IaA28R4 subtype in the United States. A rapid evolution of IaA28R4 was indicated by the observation of multiple MLST subtypes of IaA28R4 within two large outbreaks that lasted for extended periods and involved multiple swimming pools. Copyright © 2014, American Society for Microbiology. All Rights Reserved.


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.


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.


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.


Xie Y.,East China University of Science and Technology | Wei P.,East China University of Science and Technology | Li X.,KTH Royal Institute of Technology | Hong T.,East China University of Science and Technology | And 2 more authors.
Journal of the American Chemical Society | Year: 2013

Cyclization of a pentapyrrane with two terminal β-linked pyrroles afforded a dihydrosapphyrin isomer (1) with the pyrroles linked in a unique β,α-α,β mode, which was rather reactive, and thus it readily underwent a ring-contracted rearrangement to a pyrrolyl norrole (2), and succeeding ring expansion to a terpyrrole-containing isosmaragdyrin analogue (4). 1, 2, and 4 contain the internal ring pathways with a minimum of 17, 15, and 16 atoms, respectively. 1, 2, and 4 are almost nonfluorescent, whereas the complex of 2 with Zn2+ shows a distinct NIR emission peak at 741 nm. The unprecedented pyrrole transformation chemistry by confusion approach is illustrated. © 2013 American Chemical Society.


Chen B.,East China University of Science and Technology | Ding Y.,East China University of Science and Technology | Li X.,KTH Royal Institute of Technology | Zhu W.,East China University of Science and Technology | And 3 more authors.
Chemical Communications | Year: 2013

For the rational design of fluorescence "turn-on" cyanide probes, a general strategy is developed by introducing a dicyanovinyl group at the sterically demanding position of a large π framework. © The Royal Society of Chemistry 2013.


Sun Q.,East China University of Science and Technology | Qian J.,East China University of Science and Technology | Tian H.,East China University of Science and Technology | Duan L.,National Institute of Parasitic Diseases | Zhang W.,East China University of Science and Technology
Chemical Communications | Year: 2014

Two fluorescent probes SPS1 and SPS2 were designed by connecting biotin to an environment-sensitive coumarin fluorophore. Streptavidin and avidin induced dramatical fluorescence changes in both probes. SPS2 has potential in fluorescent imaging of biotin receptor-enriched tumor cells. © the Partner Organisations 2014.


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.


Gui R.,East China University of Science and Technology | Gui R.,Shanghai JiaoTong University | An X.,East China University of Science and Technology | Huang W.,East China University of Science and Technology
Analytica Chimica Acta | Year: 2013

In this study, thioglycolic acid capped-CdTe quantum dots (QDs) were modified by polyethylenimine (PEI), and then combined with fluorescein isothiocyanate (FITC) to fabricate FITC-CdTe conjugates. The self-assembly of FITC, CdTe and PEI was ascribed to electrostatic interactions in aqueous solution. The resulting conjugates were developed toward two routes. In route one, ratiometric photoluminescence (PL) intensity of conjugates (IFITC/IQDs) was almost linear toward pH from 5.3 to 8.7, and a ratiometric PL sensor of pH was favorable obtained. In route two, firstly added S2- induced remarkable quenching of QDs PL peak (at the "OFF" state), which was restored due to following addition of Cd2+ (at the "ON" state). In the conjugates, successive introduction of S2- and Cd2+ hardly influenced on FITC PL peaks. According to this PL "OFF-ON" mode, a ratiometric PL method for the detection of Cd2+ was achieved. Experimental results confirmed that the IFITC/IQDs exhibited near linear proportion toward Cd2+ concentration in the range from 0.1 to 15μM, and the limit of detection was 12nM. Interferential experiments adequately testified that the proposed sensors of pH and Cd2+ were practicable in real samples and complex systems. In comparison with conventional analytical techniques, the ratiometric PL method was simple, rapid, economic and highly selective. © 2013 Elsevier B.V.


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.


Ning Z.,East China University of Science and Technology | Ning Z.,KTH Royal Institute of Technology | Fu Y.,KTH Royal Institute of Technology | Tian H.,East China University of Science and Technology
Energy and Environmental Science | Year: 2010

The dye-sensitized solar cell (DSC) has been regarded as one of the most promising next-generation solar cells. Tremendous research efforts have been invested to improve the efficiency of solar energy conversion which is generally determined by the light harvesting efficiency, electron injection efficiency and undesirable charge recombination degree. Recently, charge recombination and electron injection efficiency, that are correlated with the open circuit voltage (Voc), have received more and more attention for their crucial roles in the further improvement of the efficiency of DSCs. In this review article, the factors that affect charge recombination and electron injection efficiency systematically discussed in order to formulate basic guidelines and strategies for improving Voc and the overall performance of DSCs is reviewed. © The Royal Society of Chemistry 2010.


Mirshafiee V.,University of Illinois at Urbana - Champaign | Mahmoudi M.,University of Illinois at Urbana - Champaign | Mahmoudi M.,Tehran University of Medical Sciences | Lou K.,University of Illinois at Urbana - Champaign | And 3 more authors.
Chemical Communications | Year: 2013

When nanoparticles (NPs) are exposed to the biological environment, their surfaces become covered with proteins and biomolecules (e.g. lipids). Here, we report that this protein coating, or corona, reduces the targeting capability of surface engineered NPs by screening the active sites of the targeting ligands. © 2013 The Royal Society of Chemistry.


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.


Patent
Shanghai Guoqiang Bioengineering Equipment Co., East China University of Science, Technology and Shanghai Cohere Electronics Technology Co. | Date: 2010-08-30

A biochemical reactor involves an online cell examination microscope (4) thereon. Said online cell examination microscope (4) comprises a main body (43), an objective lens (24), an observation entrance window (22), a sampling device (40), an external light source system (60). Said observation entrance window (22) lies in front of said main body (43) and the sampling device (40) lies in front of said observation entrance window (22). An objective lens (24) and said external light source system (60) lie behind the observation entrance window (22) in the main body (43). A reflector prism (25) is installed between the external light source system (60) and the objective lens (24). A reflector (23) lies behind the objective lens (24) and in front of the observation entrance window (22). An annular diaphragm (26) is placed in front of the reflecting prism (25). A CCD or an area image sensor (30) is arranged on the upper side of the reflectance prism (25). The sampling device (40) includes a sampling piece (21), an elastic element (38) and a mobile device. Said elastic element (38) is installed between the sampling piece (21) and the drive shaft (51) of the mobile device. A space between the head end of the sampling piece (21) and the observation entrance window (22) develops the sampling pool (50).


Li H.,East China University of Science and Technology | Li X.,KTH Royal Institute of Technology | Agren H.,KTH Royal Institute of Technology | Qu D.-H.,East China University of Science and Technology
Organic Letters | Year: 2014

Two novel star-shaped [1](n)rotaxanes with three and four identical [1]rotaxane arms but different multibranched cores were designed, synthesized, and well-characterized. In the two systems, external base-acid stimuli result in the uniform relative mechanical movement of the macrocyclic rings and threads of their [1]rotaxane arms. The energy-minimized structures of the two rotaxanes in different states were obtained using molecular dynamics simulations in acetone solution, suggesting the construction of more sophisticated molecular machines mimicking the extension and contraction motions. © 2014 American Chemical Society.


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.


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.


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.


News Article | January 10, 2016
Site: www.greencarcongress.com

« GM exploring Mobileye advanced mapping with OnStar Data; production deployment later this year | Main | New bi-modal catalyst with high selectivity for jet-fuel range hydrocarbons from F-T synthesis » Researchers from the East China University of Science and Technology, Shanghai have synthesized a flexible freestanding silicon/reduced graphene oxide (Si/rGO) hybrid film anode for Li-ion batteries. The Si/rGO films, when applied as a free-standing LIBs anode, exhibit a high reversible specific capacity of 904 mAh g−1 at 200 mA g−1 (about 2 times higher than theoretical value of graphite anode), and maintain a long cycle life (650 mAh g−1 after 150 cycles). A full flexible battery assembled based on the flexible film anode and commercial LiCoO as a cathode delivered a high specific capacity of 700 and 613 mAh g−1 at 50 mA g−1 after 15 cycles in flat and bent states, respectively. They attributed the electrochemical performance mainly to the two-dimensional hollow nanostructure of silicon and the strong synergistic effect with rGO. The researchers first synthesized hollow silicon nanosheets using a simple magnesiothermic reduction strategy. These hybridize with rGO into flexible films in a layer-by-layer assembly process. A paper on their work in published in the Journal of Power Sources.


Wu Y.,East China University of Science and Technology | Xing M.,East China University of Science and Technology | Zhang J.,East China University of Science and Technology | Zhang J.,Guizhou Normal University | Chen F.,East China University of Science and Technology
Applied Catalysis B: Environmental | Year: 2010

A visible light-active TiO2 photocatalyst modified by boron and carbon was synthesized by sol-gel followed solvothermal process. The resulting photocatalyst was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-vis absorption spectroscopy, and electron paramagnetic resonance (EPR). It was found that the boron and carbon modified TiO2 showed obvious absorption in the range 400-500 nm. XPS results suggested boron species entered into interstitial site of TiO2 matrix and formed the B-O-Ti bond, while carbon species were in the form of carbonates species. EPR results showed the existence of oxygen vacancy in carbon and boron modified TiO2. This may result in the sensitivity of the as-synthesized photocatalyst to visible light. The resulting boron and carbon modified TiO2 exhibited significantly higher photocatalytic activity than carbon modified TiO2 and undoped anatase TiO2 on the degradation of Acid Orange 7 (AO7) in aqueous solution under visible light irradiation. The presence of carbon originating from organic precursor has great influence on the surface properties of B-doped TiO2. © 2010 Elsevier B.V. All rights reserved.


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.


Lin T.,Hong Kong University of Science and Technology | Shang X.S.,East China University of Science and Technology | Adisoejoso J.,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
Journal of the American Chemical Society | Year: 2013

On-surface polymerization represents a novel bottom-up approach for producing macromolecular structures. To date, however, most of the structures formed using this method exhibit a broad size distribution and are disorderly adsorbed on the surface. Here we demonstrate a strategy of using metal-directed template to control the on-surface polymerization process. We chose a bifunctional compound which contains pyridyl and bromine end groups as the precursor. Linear template afforded by pyridyl-Cu-pyridyl coordination effectively promoted Ullmann coupling of the monomers on a Au(111) surface. Taking advantage of efficient topochemical enhancement owing to the conformation flexibility of the Cu-pyridyl bonds, macromolecular porphyrin structures that exhibit a narrow size distribution were synthesized. We used scanning tunneling microscopy and kinetic Monte Carlo simulation to gain insights into the metal-directed polymerization at the single molecule level. The results reveal that the polymerization process profited from the rich chemistry of Cu which catalyzed the C-C bond formation, controlled the size of the macromolecular products, and organized the macromolecules in a highly ordered manner on the surface. © 2013 American Chemical Society.


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.


Shamaila S.,East China University of Science and Technology | Sajjad A.K.L.,East China University of Science and Technology | Chen F.,East China University of Science and Technology | Zhang J.,East China University of Science and Technology | Zhang J.,Guizhou Normal University
Applied Catalysis B: Environmental | Year: 2010

The well-defined two-dimensional (2D) hexagonal mesoporous nanocrystalline anatase TiO2 was synthesized by the nonhydrolytic evaporation-induced co-assembly (EISA) of non-ionic amphiphilic triblock-copolymer template, titanium tetrachloride and tetrabutyl titanate. The ordered mesoporous TiO2 (M-TiO2) was loaded with different % of Bi2O3 using the wet impregnation method. For comparison Degussa P25 impregnated with Bi2O3 was also prepared. The samples were characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy, photoluminescence spectra (PLS), Fourier transform infrared spectra (FT-IR), N2 adsorption-desorption (BET) and X-ray photoelectron spectroscopy (XPS) techniques. XRD and Raman spectra showed the pore wall was composed of anatase. 1.0% Bi2O3 loaded M-TiO2 revealed the well-ordered mesostructure. UV-vis diffuse reflectance spectroscopy measurements showed an extension of light absorption into the visible region. PLS analysis indicated that the electron-hole recombination rate have been effectively inhibited when Bi2O3 was loaded with ordered M-TiO2. The photo oxidation efficiency was evaluated by methyl orange (MO) and 2,4-dichlorophenol (2,4-DCP) degradation under visible illumination. The samples loaded with different % of Bi2O3 showed higher photocatalytic activity than M-TiO2 and Bi2O3 loaded P25. The catalyst exhibited high activity due to the Bi2O3-photosensitization and well-ordered 2D pore structure. The ordered mesoporous channels facilitate mass transport of the organic pollutants. TiO2 could extend the spectral response from UV to visible region because of Bi2O3-photosensitization which make the Bi2O3 loaded M-TiO2 photocatalyst visible light responsive. © 2009 Elsevier B.V. All rights reserved.


Adisoejoso J.,Hong Kong University of Science and Technology | Li Y.,Hong Kong University of Science and Technology | Liu J.,East China University of Science and Technology | Liu P.N.,East China University of Science and Technology | Lin N.,Hong Kong University of Science and Technology
Journal of the American Chemical Society | Year: 2012

Multi-strand metallo-supramolecular polymers are self-assembled by pyridyl-functionalized porphyrin derivatives on a Au(111) surface through pyridyl-Cu-pyridyl coordination. Single-molecule-resolved characterization by scanning tunneling microscopy reveals a novel chain-growth polymerization mechanism for multi-strand supramolecular polymers. Furthermore, by varying the growth temperature and adding specific molecular modulators, both the length and the width of the polymers can be controlled. © 2012 American Chemical Society.


Shi Z.,Hong Kong University of Science and Technology | Liu J.,East China University of Science and Technology | Lin T.,Hong Kong University of Science and Technology | Xia F.,East China University of Science and Technology | And 2 more authors.
Journal of the American Chemical Society | Year: 2011

We investigated the thermodynamic processes of two-dimensional (2D) metallo-supramolecular self-assembly at molecular resolution using scanning tunneling microscopy and variable-temperature low-energy electron diffraction. On a Au(111) substrate, tripyridyl ligands coordinated with Cu in a twofold Cu-pyridyl binding mode or with Fe in a threefold Fe-pyridyl binding mode, forming a 2D open network structure in each case. The network structures exhibited remarkable thermal stability (600 K for the Cu-coordinated network and 680 K for the Fe-coordinated network). The Fe-pyridyl binding was selected thermodynamically as well as kinetically in self-assembly involving both modes. The selectivity can be effectively suppressed in a specifically designed self-assembly route. © 2011 American Chemical Society.


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.


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.


Cong Y.,East China University of Science and Technology | Tian B.,East China University of Science and Technology | Zhang J.,East China University of Science and Technology | Zhang J.,Guizhou Normal University
Applied Catalysis B: Environmental | Year: 2011

The microstructure and properties of nitrogen and lanthanum co-doped nanocrystalline titania photocatalysts have been studied. The catalyst samples were prepared in a homogeneous precipitation-hydrothermal process and characterized by XRD, XPS, UV-DRS and BET analyses. The results indicated that the nitrogen and La3+ doping could inhibit the phase transformation and crystallite growth of TiO2 and enhance the thermal stability of TiO2 structure. In addition, the experiment results showed that the thermal stability of TiO2 increased with the increasing of La3+ doping. The photocatalytic activities of samples for photodegradation of rhodamine B under visible light irradiation using different La3+ doping contents were also studied. There were optimal values of La3+ doping content for the La3+ doped and nitrogen/La3+ co-doped TiO2 corresponding the highest photodegradation percentages. The nitrogen and La3+ co-doped titania could greatly improve the photocatalytic activity in visible light irradiation, whose probable mechanism is a synergistic effect of co-doping. The nitrogen doping could narrow the band gap of titania and enhance the utilization efficiency of visible light, while the La3+ doping could accelerate the separation of photo-generated electrons and holes. Furthermore, the La3+ doping could increase the adsorption of organic pollutants on the surface of photocatalyst. © 2010 Elsevier B.V.


Sun H.,Shaanxi Normal University | Fan S.,Shaanxi Normal University | Zhang H.,Shaanxi Normal University | Gong S.,East China University of Science and Technology
Physical Review B - Condensed Matter and Materials Physics | Year: 2013

An asymmetric double quantum well (QW) structure with resonant tunneling is suggested to achieve highly efficient four-wave mixing (FWM). We analytically demonstrate that resonant tunneling can induce a highly efficient mixing wave in such a semiconductor structure with a low-light pump wave. In particular, the FWM conversion efficiency can be enhanced dramatically in the vicinity of the center frequency with small propagation distance. This interesting scheme may be used to generate coherent long-wavelength radiation in solid-state systems. © 2013 American Physical Society.


Sajjad S.,East China University of Science and Technology | Leghari S.A.K.,East China University of Science and Technology | Chen F.,East China University of Science and Technology | Zhang J.,East China University of Science and Technology | Zhang J.,Guizhou Normal University
Chemistry - A European Journal | Year: 2010

A controllable and reproducible synthesis of highly ordered two-dimensional hexagonal mesoporous, crystalline bismuth-doped TiO2 nanocomposites with variable Bi ratios is reported here. Analyses by transmission electron microscopy, X-ray diffraction, Raman, and X-ray photoelectron spectroscopy reveal that the well-ordered mesostructure is doped with Bi, which exists as Bi3+ and Bi(3+x+). The Bi-doped mesoporous TiO2 (ms-TiO2) samples exhibit improved photocatalytic activities for simultaneous phenol oxidation and chromium reduction in aqueous suspension under visible and UV light over the pure ms-TiO2, P-25, and conventional Bi-doped titania. The high catalytic activity is due to both the unique structural characteristics and the Bi doping. This new material extends the spectral response from UV to the visible region, and reduces electron-hole recombination, which renders the 2.0 % Bi-doped ms-TiO2 photocatalyst highly responsive to visible light. Bismuth cleans up: Highly ordered 2D hexagonal mesoporous (ms) crystalline Bi-doped TiO2 nanocomposites that are active catalysts in the visible region have been synthesized (see figure). The photocatalytic activity of 2.0 % Bi-doped ms-TiO2 is far superior to other TiO2 catalysts for the simultaneous degradation of phenol and reduction of chromium under visible illumination. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhu X.,East China University of Science and Technology | Zhang J.,East China University of Science and Technology | Zhang J.,Guizhou Normal University | Chen F.,East China University of Science and Technology
Chemosphere | Year: 2010

Bismuth titanate (Bi12TiO20) nanostructures with different morphologies were synthesized hydrothermally using Bi(NO3)3 and Ti(SO4)2 in the presence of polyethylene glycol (PEG). X-ray diffraction (XRD) proved that the samples were in pure cubic phase. UV-visible diffuse reflection spectra showed the band gap of Bi12TiO20 is about 2.7 eV. Brunauer-Emmett-Teller (BET) analysis proved that the Bi12TiO20 samples have higher surface areas than samples prepared by methods reported previously. Photocatalytic degradation of acid orange 7 (AO7) under visible light illumination was used to evaluate the photocatalytic ability of samples. The photocatalytic results showed Bi12TiO20 could degrade AO7 very efficiently and had higher photocatalytic activity than traditional N-doped TiO2. In addition, we have also discussed factors that have major effect on reaction efficiency. BET surface area played the most important role in the photocatalytic degradation of AO7. The crystallinity of the samples is another important factor which can also influence photocatalysis results. © 2010 Elsevier Ltd. All rights reserved.


Wang E.,Chalmers University of Technology | Ma Z.,Linköping 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.


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.


Patent
East China University of Science, Technology and Shanghai Shengnong Pesticide Co. | Date: 2011-10-19

The heterocyclic nitrogenous or oxygenous compounds of formula (A), (B), (C) or (D) formed from dialdehydes, their optical isomers, cis- and trans- isomers, or agrochemically acceptable salts, their preparation methods, agrochemical compositions comprising the compounds and the uses thereof are provided. The compounds and their derivatives have high insecticidal activities to several farming and forestry pests including homoptera and lepidoptera pests, such as aphis, fulgorid, whitefly, leafhopper, common thrips, cotton bollworm, cabbage caterpillar, cabbage moth, cotton leafworm, armyworm and so on.


News Article | March 30, 2016
Site: phys.org

For the first time, scientists have overcome the challenge of breaking down raw biomass without the need for chemical pre-treatment, and have produced record high amounts of clean liquid hydrocarbon fuel as a result. This brings us one step closer to lessening our dependence on fossil fuels, and is an important development in our shift towards renewable energy. The ability to produce sustainable fuel from renewable biomass is becoming increasingly important as we move away from our dependency on fossil fuels. The production and utilisation of biomass, or plant material, offers an energy alternative that is almost carbon neutral, as the carbon dioxide is recycled in plant photosynthesis. In plants, the woody material that is used to produce fuel consists of three different components: cellulose, hemicellulose and lignin. Lignin is a challenge to the production of biofuels, as it is difficult to break down and convert into useful fuel, often requiring high levels of energy or the use of corrosive chemicals. Therefore, up to a third of plant material can go to waste or be burned as low-value fuel. A team of scientists from The University of Manchester and East China University of Science and Technology stewed a catalyst - made up of the metal complex niobium phosphate, with small particles of platinum dotted across the surface - with raw wood sawdust for 20 hours at 190 degrees Celsius, and a pressure of 50 atmospheres. The results, published in Nature Communications, show that the catalyst was able to directly break down and convert the lignin, which potentially offers the future development of catalysts for converting biomass into fuel. Dr Yang used the Science & Technology Facilities Council's ISIS Neutron and Muon source - often described as a 'super-microscope' - to study the biomass and catalyst at the molecular level. Using an instrument called TOSCA, Dr Yang and ISIS scientist Dr Stewart Parker used neutrons to see how a model of lignocellulose interacted with the surface of the catalyst to produce useful fuel. "The conversion of biomass into fuels typically requires separations and pre-treatments to the raw biomass, thus suffering high energy penalties. This catalyst showed exceptionally high activity in splitting the carbon-oxygen bonds, the most challenging step in the conversion of lignocellulosic biomass. This new catalytic process can therefore directly convert raw biomass to liquid fuels without separations or chemical pre-treatments, leading to significant potential energy savings," says Dr Sihai Yang, lead author of the study.


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

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


Yang S.,Max Planck Institute for Polymer Research | Zhan L.,East China University of Science and Technology | Zhan L.,Rice University | Xu X.,East China University of Science and Technology | And 3 more authors.
Advanced Materials | Year: 2013

It is demonstrated that graphene-based porous silica sheets can serve as an efficient carrier support for PEI via a simple nanocasting technology. The resulting materials possess thin nature, high PEI loading content and high thermal-conductivity. Such features are favorable for the efficient diffusion and adsorption of CO2 as well as the rapid thermal transfer during the CO2 capture process. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu X.,East China University of Science and Technology | Liu X.,CAS Shanghai Institute of Materia Medica | Jiang H.,CAS Shanghai Institute of Materia Medica | Li H.,East China University of Science and Technology
Journal of Chemical Information and Modeling | Year: 2011

We developed a novel approach called SHAFTS (SHApe-FeaTure Similarity) for 3D molecular similarity calculation and ligand-based virtual screening. SHAFTS adopts a hybrid similarity metric combined with molecular shape and colored (labeled) chemistry groups annotated by pharmacophore features for 3D similarity calculation and ranking, which is designed to integrate the strength of pharmacophore matching and volumetric overlay approaches. A feature triplet hashing method is used for fast molecular alignment poses enumeration, and the optimal superposition between the target and the query molecules can be prioritized by calculating corresponding "hybrid similarities". SHAFTS is suitable for large-scale virtual screening with single or multiple bioactive compounds as the query "templates" regardless of whether corresponding experimentally determined conformations are available. Two public test sets (DUD and Jains sets) including active and decoy molecules from a panel of useful drug targets were adopted to evaluate the virtual screening performance. SHAFTS outperformed several other widely used virtual screening methods in terms of enrichment of known active compounds as well as novel chemotypes, thereby indicating its robustness in hit compounds identification and potential of scaffold hopping in virtual screening. © 2011 American Chemical Society.


Qi D.,East China University of Science and Technology | Lu L.,East China University of Science and Technology | Wang L.,East China University of Science and Technology | Zhang J.,East China University of Science and Technology | Zhang J.,Tsinghua University
Journal of the American Chemical Society | Year: 2014

Highly sensitive surface-enhanced Raman scattering (SERS) detection was achieved on plasmon-free TiO2 photonic artificial microarray, which can be quickly recovered under simulated solar light irradiation and repeatedly used. The sensitive detection performance is attributed to the enhanced matter-light interaction through repeated and multiple light scattering in photonic microarray. Moreover, the SERS sensitivity is unprecedentedly found to be dependent on the different light-coupling performance of microarray with various photonic band gaps, where microarray with band gap center near to laser wavelength shows a lower SERS signal due to depressed light propagation, while those with band gap edges near to laser wavelength show higher sensitivity due to slow light effect. © 2014 American Chemical Society.


Yao X.,East China University of Science and Technology | Li T.,East China University of Science and Technology | Wang S.,Zhanjiang Normal University | Ma X.,East China University of Science and Technology | Tian H.,East China University of Science and Technology
Chemical Communications | Year: 2014

A photochromic supramolecular polymer based on bis-p-sulfonatocalix[4]arene recognition with a dithienylethene derivative in aqueous solution was fabricated. The resultant polymer showed good photochromic behaviour with obvious colour switching and a morphology change under alternative UV/Vis light stimuli. © 2014 the Partner Organisations.


Qi D.,East China University of Science and Technology | Xing M.,East China University of Science and Technology | Zhang J.,East China University of Science and Technology | Zhang J.,Tsinghua University
Journal of Physical Chemistry C | Year: 2014

A novel hydrophobic photocatalyst carbon-doped TiO2/MCF-F was prepared by using silica mesoporous cellular foam (MCF) as host material, glucose as carbon source, and NH4F as hydrophobic modifying agent. It was confirmed that titania nanoparticles were loaded in pore of MCF by XRD, N2 sorption isotherms, and TEM. The loaded titania nanoparticles exhibited higher photocatalytic performance. UV-vis absorption spectra and XPS suggested carbon atoms were doped in the lattice of titania by replacing titanium atoms and narrowed the band gap so that visible light absorption and photocatalytic activity of the photocatalyst were highly promoted. On the other hand, water contact angle measurement and XPS proved that the photocatalyst was endowed with hydrophobic property, which was caused by Si-F bonds. Carbon-doped TiO2/MCF-F photocatalyst showed good adsorptive ability and photocatalytic activity in the photodegradation test of methyl orange under visible light. © 2014 American Chemical Society.


Li X.,East China University of Science and Technology | Liu P.,East China University of Science and Technology | Mao Y.,East China University of Science and Technology | Xing M.,East China University of Science and Technology | And 2 more authors.
Applied Catalysis B: Environmental | Year: 2015

A series of mesoporous TiO2 spheres of nanosized crystals with high monodispersity and dimensional homogeneity are synthesized by a simple reflux method. In order to improve the visible light response and to further narrow the band bap of TiO2 sphere, nitrogen is used as the dopant in a hydrothermal method. Different from the traditional nitrogen doping in TiO2 solid sphere, the nitrogen is uniformly distributed from bulk to the surface of mesoporous TiO2 sphere, which is beneficial to the generation of the successive energy bands inside the TiO2 band gap. Interestingly, the XPS results indicate that the nitrogen doping concentration could reach 1.31% (only 0.17% for nitrogen doped solid TiO2 sphere), owing to the homogeneous doping in the mesoporous TiO2 spheres. The nitrogen doped TiO2 spheres exhibit such excellent characteristics as high specific area, relatively small particle size, pure anatase phase and excellent UV-vis absorption capacity in the range of 400-800nm, which are all beneficial to the photo-degradation of Rhodamine B under the visible light irradiation. The high photocatalytic activity could be ascribed to the homogeneous nitrogen doping on the deep adjustment of energy band of TiO2 sphere from the bulk to the surface. © 2014 Elsevier B.V.


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.


Cai M.,East China University of Science and Technology | Chen J.,East China University of Science and Technology | Taha M.,Jean Monnet University
Inorganic Chemistry Communications | Year: 2010

Two novel complexes, Na 3Y(pydc) 3·12H 2O (1) and Y 2(pydc)(OH) 4·3H 2O (2) (pydc = 2,6-pyridinedicarboxylate), were synthesized by yttrium (III) nitrate and pydcH 2 with different molar ratios. The elemental analysis, IR spectra and single crystal X-ray diffraction were used to determine the structure of complexes. The thermal decompositions and antimicrobial activities against Bacillus coli and Staphylococcus aureus were recorded and interpreted for both. © 2009 Elsevier B.V. All rights reserved.


Fang W.,East China University of Science and Technology | Xing M.,East China University of Science and Technology | Zhang J.,East China University of Science and Technology | Zhang J.,Tsinghua University
Applied Catalysis B: Environmental | Year: 2014

Ti3+ self-doped TiO2 are successfully prepared via a simple one-step calcination method, by using low-cost NaBH4 as the reductant. The as-prepared samples are characterized by different techniques such as X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy (UV-vis DRS), Electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), and Fourier transformation infrared spectroscopy (FTIR). EPR spectra confirm the presence of Ti3+ in the bulk of the samples rather than on the surface, which is the reason for the high photocatalytic performance of the catalyst under visible light irradiation. It is worth noting that the visible light absorption is enhanced after HCl washing, and the photocatalytic activity of Ti3+ self-doped TiO2 is proportional to the concentration of the doped Ti3+. Interestingly, the photocatalytic activity of the catalyst under UV light also increases after HCl washing treatment, which is caused by the increase of BET surface area. © 2014 Elsevier B.V.


He X.-P.,East China University of Science and Technology | Zang Y.,CAS Shanghai Institute of Materia Medica | James T.D.,University of Bath | Li J.,CAS Shanghai Institute of Materia Medica | Chen G.-R.,East China University of Science and Technology
Chemical Society Reviews | Year: 2015

Construction of composite materials based on the self-assembly of fluorescently labeled biomolecules with a variety of micro- or nano-quenching materials (by the Förster Resonance Energy Transfer mechanism) for the fluorogenic recognition of disease-related proteins has become a dynamic research topic in the field of fluorescence recognition. Here we summarize the recent progress on the composition of fluorescence dye-labeled biomolecules including sugars, peptides and nucleotides with organic (graphene and carbon nanotubes) and inorganic (gold nanoparticles) materials. Their application in the fluorescence detection of proteins and enzymes on both the molecular and cellular levels is discussed. Perspectives are proposed with respect to the future directions of employing these composite materials in the recognition of pathological proteins. This journal is © The Royal Society of Chemistry.


Liu J.,East China University of Science and Technology | Lei M.,CAS Shanghai Institute of Materia Medica | Hu L.,East China University of Science and Technology | Hu L.,CAS Shanghai Institute of Materia Medica
Green Chemistry | Year: 2012

An environmentally benign and efficient method has been developed for the synthesis of a series of benzo[4,5]imidazo[1,2-a]pyrimido[4,5-d]pyrimidin-4(1H)- one derivatives in aqueous media under catalyst-free conditions by simply combining 2-aminobenzimidazole, aldehyde, and cyanoacetamide. The advantages of this method are that it is catalyst-free, has an easy workup, provides excellent yields, and uses water as the solvent which is considered to be relatively environmentally benign. © 2012 The Royal Society of Chemistry.


Liu J.,East China University of Science and Technology | Lei M.,CAS Shanghai Institute of Materia Medica | Hu L.,East China University of Science and Technology | Hu L.,CAS Shanghai Institute of Materia Medica
Green Chemistry | Year: 2012

A straightforward and general method has been developed for the synthesis of benzo[4,5]imidazo[1,2-a]pyrimidine and [1,2,4]triazolo[1,5-a]pyrimidine derivatives by simply combining 2-aminobenzimidazole or 3-amino-1,2,4-triazole, aldehyde, and β-dicarbonyl compound in the presence of a catalytic amount of thiamine hydrochloride (VB 1). The advantages of this method are the use of an inexpensive and readily available catalyst, easy workup, improved yields, and the use of water as the solvent that is considered to be relatively environmentally benign. © The Royal Society of Chemistry 2012.


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.


Patent
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.


Patent
East China University of Science, Technology, Jiaxing Zeyuan Bio Products Co. and Shanghai Zeyuan Marine Biotechnology Co. | Date: 2015-06-03

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.


News Article | December 27, 2016
Site: www.eurekalert.org

The Biophysical Society has announced the winners of its international travel grants to attend the Biophysical Society's 61st Annual Meeting in New Orleans, February 11-15, 2017. The purpose of these awards is to foster and initiate further interaction between American biophysicists and scientists working in countries experiencing financial difficulties. Recipients of this competitive award are chosen based on scientific merit and their proposed presentation at the meeting. They will be honored at a reception on Sunday, February 12 at the Ernest N. Morial Convention Center. The 2017 recipients of the International Travel Award, along with their institutional affiliation and abstract title, are listed below. Ana F. Guedes, Institute of Molecular Medicine, Portugal, ATOMIC FORCE MICROSCOPY AS A TOOL TO EVALUATE THE RISK OF CARDIOVASCULAR DISEASES IN PATIENTS. Karishma Bhasne Mohali, Indian Institute of Science Education and Research (IISER), A TALE OF TWO AMYLOIDOGENIC INTRINSICALLY DISORDERED PROTEINS: INTERPLAY OF TAU AND α-SYNUCLEIN. Chan Cao, East China University of Science and Technology, DIRECT IDENTIFICATION OF ADENINE, THYMINE, CYTOSINE AND GUANINE USING AEROLYSIN NANOPORE. Venkata Reddy Chirasani, Indian Institute of Technology Madras, LIPID TRANSFER MECHANISM OF CETP BETWEEN HDL AND LDL: A COARSEGRAINED SIMULATION STUDY. Assaf Elazar, Weizmann Institute of Science, Israel, DECIPHERING MEMBRANE PROTEIN ENERGETICS USING DEEP SEQUENCING; TOWARDS ROBUST DESIGN AND STRUCTURE PREDICTION OF MEMBRANE PROTEINS. Manuela Gabriel, University of Buenos Aires, Argentina, 3D ORBITAL TRACKING OF SINGLE GOLD NANOPARTICLES: A NEW APPROACH TO STUDY VESICLE TRAFFICKING IN CHROMAFFIN CELLS. Farah Haque National Centre for Biological Sciences, India, A NEW HUMANIZED MOUSE MODEL FOR STUDYING INHERITED CARDIOMYOPATHIC MUTATIONS IN THE MYH7 GENE. Stephanie Heusser, Stockholm University, Switzerland, STRUCTURAL AND FUNCTIONAL EVIDENCE FOR MULTI-SITE ALLOSTERY MEDIATED BY GENERAL ANESTHETICS IN A MODEL LIGAND-GATED ION CHANNEL. Amir Irani, Massey University, New Zealand, HOMOGALACTURONANS ILLUMINATE THE ROLE OF COUNTERION CONDENSATION IN POLYELECTROLYTE TRANSPORT. Olfat Malak, University of Nantes, France, HIV-TAT INDUCES A DECREASE IN IKR AND IKS VIA REDUCTION IN PHOSPHATIDYLINOSITOL-(4,5)-BISPHOSPHATE AVAILABILITY. CONFORMATIONAL TRANSITION AND ASSEMBLY OF E.COLI CYTOLYSIN A PORE FORMING TOXIN BY SINGLE MOLECULE FLUORESCENCE. Sabrina Sharmin, Shizuoka University, Japan, EFFECTS OF LIPID COMPOSITIONS ON THE ENTRY OF CELL PENETRATING PEPTIDE OLIGOARGININE INTO SINGLE VESICLES. Xin Shi, East China University of Science and Technology, DIRECT OBSERVATION OF SINGLE BIOPOLYMER FOLDING AND UNFOLDING PROCESS BY SOLIDSTATE NANOPORE. Omar Alijevic, University of Lausanne, Switzerland, ANALYSIS OF GATING OF ACID-SENSING ION CHANNELS (ASICS) UNDER RAPID AND SLOW PH CHANGES. Swapna Bera, Bose Institute, India, BIOPHYSICAL INSIGHTS INTO THE MEMBRANE INTERACTION OF THE CORE AMYLOID-FORMING Aβ40 FRAGMENT K16-K28 AND ITS ROLE IN THE PATHOGENESIS OF ALZHEIMER'S DISEASE. Anais Cassaignau, University College London, United Kingdom, STRUCTURAL INVESTIGATION OF AN IMMUNOGLOBULIN DOMAIN ON THE RIBOSOME USING NMR SPECTROSCOPY. Bappaditya Chandra, Tata Institute of Fundamental Research, India, SECONDARY STRUCTURE FLIPPING CONNECTED TO SALT-BRIDGE FORMATION CONVERTS TOXIC AMYLOID-β40 OLIGOMERS TO FIBRILS. Gayathri Narasimhan, Cinvestav, Mexico, ANTIHYPERTROPHIC EFFECTS OF DIAZOXIDE INVOLVES CHANGES IN MIR-132 EXPRESSION IN ADULT RAT CARDIOMYCYTES. Giulia Paci, European Molecular Biology Laboratory, Germany, FOLLOWING A GIANT'S FOOTSTEPS: SINGLE-PARTICLE AND SUPER-RESOLUTION APPROACHES TO DECIPHER THE NUCLEAR TRANSPORT OF HEPATITIS B VIRUS CAPSIDS. Bizhan Sharopov, Bogomoletz Institute of Physiology National Academy of Sciences of Ukraine, DISSECTING LOCAL AND SYSTEMIC EFFECTS OF TRPV1 ON BLADDER CONTRACTILITY IN DIABETES. Chao Sun, East China Normal University, FUNCTION OF BACTERIORUBERIN IN ARCHAERHODOPSIN 4, FROM EXPRESSION TO CHARACTERIZATION. Matthew Batchelor, University of Leeds, United Kingdom STRUCTURAL DYNAMICS IN THE MYOSIN 7A SINGLE α-HELIX DOMAIN. Daniel Havelka, Czech Academy of Sciences, MICROVOLUME DIELECTRIC SPECTROSCOPY AND MOLECULAR DYNAMICS OF AMINO ACIDS. Ivan Kadurin, University College London, United Kingdom, INVESTIGATION OF THE PROTEOLYTIC CLEAVAGE OF α2δ SUBUNITS: A MECHANISTIC SWITCH FROM NHIBITION TO ACTIVATION OF VOLTAGE-GATED CALCIUM CHANNELS? Linlin Ma, University of Queensland, Australia, NOVEL HUMAN EAG CHANNEL ANTAGONISTS FROM SPIDER VENOMS. Ivana Malvacio, University of Cagliari, Italy, MOLECULAR INSIGHTS ON THE RECOGNITION OF SUBSTRATES BY THE PROMISCUOUS EFFLUX PUMP ACRB. Cristina Moreno Vadillo, Cardiovascular Research Institute Maastricht, Netherlands, RESTORING DEFECTIVE CAMP-DEPENDENT UPREGULATION IN LONG-QT SYNDROME TYPE-1 THROUGH INTERVENTIONS THAT PROMOTE IKS CHANNEL OPENING. Melanie Paillard, Claude Bernard University Lyon 1, France, TISSUE-SPECIFIC MITOCHONDRIAL DECODING OF CYTOPLASMIC CA2+ SIGNALS IS CONTROLLED BY THE STOICHIOMETRY OF MICU1/2 AND MCU. Mohammed Mostafizur Rahman, Institute for Stem Cell Biology and Regenerative Medicine, India, STRESS-INDUCED DIFFERENTIAL REGULATION LEADS TO DECOUPLING OF THE ACTIVITY BETWEEN MPFC AND AMYGDALA. Marcin Wolny, University of Leeds, United Kingdom, DESIGN AND CHARACTERIZATION OF LONG AND STABLE DE NOVO SINGLE α-HELIX DOMAINS. Elvis Pandzic, University of New South Wales, Australia, VELOCITY LANDSCAPES RESOLVE MULTIPLE DYNAMICAL POPULATIONS FROM FLUORESCENCE IMAGE TIME SERIES. The Biophysical Society, founded in 1958, is a professional, scientific Society established to encourage development and dissemination of knowledge in biophysics. The Society promotes growth in this expanding field through its annual meeting, monthly journal, and committee and outreach activities. Its 9000 members are located throughout the U.S. and the world, where they teach and conduct research in colleges, universities, laboratories, government agencies, and industry. For more information on these awards, the Society, or the 2017 Annual Meeting, visit http://www.


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.


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.


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.


Hu J.,Harbin Institute of Technology | Wang Z.,Brunel University | Niu Y.,East China University of Science and Technology | Stergioulas L.K.,Brunel University
International Journal of Robust and Nonlinear Control | Year: 2012

In this paper, the H ∞ sliding mode observer (SMO) design problem is investigated for a class of nonlinear discrete time-delay systems. The nonlinear descriptions quantify the maximum possible derivations from a linear model, and the system states are allowed to be immeasurable. Attention is focused on the design of a discrete-time SMO such that the asymptotic stability as well as the H ∞ performance requirement of the error dynamics can be guaranteed in the presence of nonlinearities, time delay and external disturbances. Firstly, a discrete-time discontinuous switched term is proposed to make sure that the reaching condition holds. Then, by constructing a new Lyapunov-Krasovskii functional based on the idea of 'delay fractioning' and by introducing some appropriate free-weighting matrices, a sufficient condition is established to guarantee the desired performance of the error dynamics in the specified sliding mode surface by solving a minimization problem. Finally, an illustrative example is given to show the effectiveness of the designed SMO design scheme. Copyright © 2011 John Wiley & Sons, Ltd. Copyright © 2011 John Wiley & Sons, Ltd.


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.


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.


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.


Wang J.,East China University of Science and Technology | Wang J.,CAS Shanghai Advanced Research Institute | Xi J.,East China University of Science and Technology | Wang Y.,East China University of Science and Technology
Green Chemistry | Year: 2015

Recently, research on the catalytic production of glucose, the first platform chemical in biorefinery, has become attractive in catalysis studies and the chemical/fuel industry owing to its broad applications. It opens up a new route for achieving sustainable chemical production and energy supply. From this viewpoint, this contribution attempts to overview the recent advances in the catalytic routes for the synthesis of glucose from lignocellulosic biomass over various homogeneous and heterogeneous catalysts. © 2015 The Royal Society of Chemistry.


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.


Wang M.,East China University of Science and Technology | Wang Z.,East China University of Science and Technology | Shi Y.-H.,East China University of Science and Technology | Shi X.-X.,East China University of Science and Technology | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2011

An exo-lent catalyst: An N,O-ligand/Cu(OAc)2 derived chiral complex is an excellent catalyst for inducing asymmetry in the catalytic enantioselective 1,3-dipolar cycloadditions of azomethine ylides with various alkylidene malonates. A series of highly functionalized exo-pyrrolidines were obtained in excellent yields (80-99 %) and enantioselectivities (91-99 %ee; see scheme; M.S.: molecular sieve). Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Jones S.,University of Oxford | Qu J.,University of Oxford | Tedsree K.,Burapha University | Gong X.-Q.,East China University of Science and Technology | Tsang S.C.E.,University of Oxford
Angewandte Chemie - International Edition | Year: 2012

A remarkable effect from the modification of electronic and geometric properties of Pd nanoparticles by the use of polymer pendant groups bound to the surface of palladium nanoparticles is reported. The degree of electron promotion to the Pd nanoparticles under ambient conditions was found to be dependent on the availability of the lone pair electrons of the pendant groups. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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.


Sih G.C.,Lehigh University | Sih G.C.,East China University of Science and Technology
Theoretical and Applied Fracture Mechanics | Year: 2010

Multiscale material intends to enhance the strength and life of mechanical systems by matching the transmitted spatiotemporal energy distribution to the constituents at the different scale, say-macro, micro, nano, and pico,-, depending on the needs. Lower scale entities are, particularly, critical to small size systems. Large structures are less sensitive to microscopic effects. Scale shifting laws will be developed for relating test data from nano-, micro-, and macro-specimens. The benefit of reinforcement at the lower scale constituents needs to be justified at the macroscopic scale. Filling the void and space in regions of high energy density is considered. Material inhomogeneity interacts with specimen size. Their combined effect is non-equilibrium. Energy exchange between the environment and specimen becomes increasingly more significant as the specimen size is reduced. Perturbation of the operational conditions can further aggravate the situation. Scale transitional functions f j j+1 and/or f j/j+1 are introduced to quantify these characteristics. They are represented, respectively, by (f ma mi, f mi na, f na pi), and (f mi/ma, f na/mi, f pi/na) The abbreviations pi, na, mi, and ma refer to pico, nano, micro and macro. Local damage is assumed to initiate at a small scale, grows to a larger scale, and terminate at an even larger scale. The mechanism of energy absorption and dissipation will be introduced to develop a consistent book keeping system. Compaction of mass density for constituents of size 10 -12, 10 -9, 10 -6, 10 -3 m, will be considered. Energy dissipation at all scales must be accounted for. Dissipations at the smaller scale must not only be included but they must abide by the same physical and mathematical interpretation, in order to avoid inconsistencies when making connections with those at the larger scale where dissipations are eminent. Three fundamental Problems I, II, and III are stated. They correspond to the commonly used service conditions. Reference is made to a Representative Tip (RT), the location where energy absorption and dissipation takes place. The RT can be a crack tip or a particle. At the larger size scales, RT can refer to a region. Scale shifting of results from the very small to the very large is needed to identify the benefit of using multiscale materials. © 2010 Elsevier Ltd.


Shi L.,East China University of Science and Technology | Jing C.,East China University of Science and Technology | Ma W.,East China University of Science and Technology | Li D.-W.,East China University of Science and Technology | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2013

A method based on plasmon resonance Rayleigh scattering (PRRS) spectroscopy and dark-field microscopy (DFM) was established for the real-time monitoring of a click reaction at the single-nanoparticle level. Click reactions on the surface of single gold nanoparticles (GNPs) result in interparticle coupling, which leads to a red-shift of the λmax (Δλ max=43nm) in the PRRS spectra and a color change of the single gold nanoparticles in DFM (from green to orange). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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.


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.


Xu Z.,East China University of Science and Technology | Xu L.,East China University of Science and Technology | Xu L.,East China Nomal University | Zhou J.,East China University of Science and Technology | And 3 more authors.
Chemical Communications | Year: 2012

A new ratiometric fluorescence probe E1 based on an excited-state intramolecular proton transfer (ESIPT) mechanism for detection of hydrogen sulfide (H2S) is reported. E1 responds to H2S quickly and showed a 30-fold fluorescence enhancement in 2 minutes. Moreover, E1 can detect H2S quantitatively with a detection limit as low as 0.12 μM in aqueous solution. Its potential for biological applications was confirmed by employing it for fluorescence imaging of H2S in living cells. © 2012 The Royal Society of Chemistry.


Wu X.,East China University of Science and Technology | Sun X.,Zhejiang University | Guo Z.,East China University of Science and Technology | Tang J.,Zhejiang University | And 4 more authors.
Journal of the American Chemical Society | Year: 2014

In vivo monitoring of the biodistribution and activation of prodrugs is urgently required. Near infrared (NIR) fluorescence-active fluorophores with excellent photostability are preferable for tracking drug release in vivo. Herein, we describe a NIR prodrug DCM-S-CPT and its polyethylene glycol-polylactic acid (PEG-PLA) loaded nanoparticles as a potent cancer therapy. We have conjugated a dicyanomethylene-4H-pyran derivative as the NIR fluorophore with camptothecin (CPT) as the anticancer drug using a disulfide linker. In vitro experiments verify that the high intracellular glutathione (GSH) concentrations in tumor cells cause cleavage of the disulfide linker, resulting in concomitantly the active drug CPT release and significant NIR fluorescence turn-on with large Stokes shift (200 nm). The NIR fluorescence of DCM-S-CPT at 665 nm with fast response to GSH can act as a direct off-on signal reporter for the GSH-activatable prodrug. Particularly, DCM-S-CPT possesses much better photostability than ICG, which is highly desirable for in situ fluorescence-tracking of cancer chemotherapy. DCM-S-CPT has been successfully utilized for in vivo and in situ tracking of drug release and cancer therapeutic efficacy in living animals by NIR fluorescence. DCM-S-CPT exhibits excellent tumor-activatable performance when intravenously injected into tumor-bearing nude mice, as well as specific cancer therapy with few side effects. DCM-S-CPT loaded in PEG-PLA nanoparticles shows even higher antitumor activity than free CPT, and is also retained longer in the plasma. The tumor-targeting ability and the specific drug release in tumors make DCM-S-CPT as a promising prodrug, providing significant advances toward deeper understanding and exploration of theranostic drug-delivery systems. © 2014 American Chemical Society.


Li M.,University of Bath | Wu X.,East China University of Science and Technology | Wang Y.,East China University of Science and Technology | Li Y.,East China University of Science and Technology | And 3 more authors.
Chemical Communications | Year: 2014

A novel near-infrared (NIR) and colorimetric fluorescent molecular probe based on a dicyanomethylene-4H-pyran chromophore for the selective detection of glutathione in living cells has been developed. The fluorescence OFF-ON switch is triggered by cleavage of the 2,4-dinitrobenzensulfonyl (DNBS) unit by the interaction with GSH. © 2014 The Royal Society of Chemistry.


Wang J.,East China University of Science and Technology | Mora-Sero I.,Jaume I University | Pan Z.,East China University of Science and Technology | Zhao K.,East China University of Science and Technology | And 5 more authors.
Journal of the American Chemical Society | Year: 2013

Searching suitable panchromatic QD sensitizers for expanding the light-harvesting range, accelerating charge separation, and retarding charge recombination is an effective way to improve power conversion efficiency (PCE) of quantum-dot-sensitized solar cells (QDSCs). One possible way to obtain a wide absorption range is to use the exciplex state of a type-II core/shell- structured QDs. In addition, this system could also provide a fast charge separation and low charge-recombination rate. Herein, we report on using a CdTe/CdSe type-II core/shell QD sensitizer with an absorption range extending into the infrared region because of its exciplex state, which is covalently linked to TiO2 mesoporous electrodes by dropping a bifunctional linker molecule mercaptopropionic acid (MPA)-capped QD aqueous solution onto the film electrode. High loading and a uniform distribution of QD sensitizer throughout the film electrode thickness have been confirmed by energy dispersive X-ray (EDX) elemental mapping. The accelerated electron injection and retarded charge-recombination pathway in the built CdTe/CdSe QD cells in comparison with reference CdSe QD-based cells have been confirmed by impedance spectroscopy, fluorescence decay, and intensity-modulated photocurrent/photovoltage spectroscopy (IMPS/IMVS) analysis. With the combination of the high QD loading and intrinsically superior optoelectronic properties of type-II core/shell QD (wide absorption range, fast charge separation, and slow charge recombination), the resulting CdTe/CdSe QD-based regenerative sandwich solar cells exhibit a record PCE of 6.76% (Jsc = 19.59 mA cm-2, Voc = 0.606 V, and FF = 0.569) with a mask around the active film under a full 1 sun illumination (simulated AM 1.5), which is the highest reported to date for liquid-junction QDSCs. © 2013 American Chemical Society.


Chen L.,East China University of Science and Technology | Wu J.,East China University of Science and Technology | Schmuck C.,University of Duisburg - Essen | Tian H.,East China University of Science and Technology
Chemical Communications | Year: 2014

A bis-spiropyran functionalized peptide 1, which exhibits good cell-permeability, excellent biocompatibility and low cytotoxicity, has been developed for reversible and real-time lysosomal tracking. This journal is © the Partner Organisations 2014.


Zhang M.,East China University of Science and Technology | Yin B.-C.,East China University of Science and Technology | Tan W.,University of Florida | Ye B.-C.,East China University of Science and Technology
Biosensors and Bioelectronics | Year: 2011

We have designed a versatile molecular beacon (MB)-like probe for the multiplex sensing of targets such as sequence-specific DNA, protein, metal ions and small molecule compounds based on the self-assembled ssDNA-graphene oxide (ssDNA-GO) architecture. The probe employs fluorescence " on/off" switching strategy in a single step in homogeneous solution. Compared to traditional molecular beacons, the proposed design is simple to prepare and manipulate and has little background interference, but still gives superior sensitivity and rapid response. More importantly, this ssDNA-GO architecture can serve as a universal beacon platform by simply changing the types of ssDNA sequences for the different targets. In this work, the ssDNA-GO architecture probe has been successfully applied in the multiplex detection of sequence-specific DNA, thrombin, Ag+, Hg2+ and cysteine, and the limit of detection was 1nM, 5nM, 20nM, 5.7nM and 60nM, respectively. The results demonstrate that the ssDNA-GO architecture can be an excellent and versatile platform for sensing multiplex analytes, easily replacing the universal molecular beacon. © 2011 Elsevier B.V.


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.


Li Y.,East China University of Science and Technology | Du W.,Zhejiang Medical College | Deng W.-P.,East China University of Science and Technology
Tetrahedron | Year: 2012

A NHCs-mediated benzoates formation was developed by treatment of aromatic aldehydes with alkyl halides in the presence of oxygen. Corresponding benzoate derivatives were obtained in high yields up to 99%. The reaction mechanism was also discussed and a NHCs-mediated O-alkylation and subsequent oxidation process was proposed. © 2011 Elsevier Ltd. All rights reserved.


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.


Li M.,University of Bath | Guo Z.,East China University of Science and Technology | Zhu W.,East China University of Science and Technology | Marken F.,University of Bath | James T.D.,University of Bath
Chemical Communications | Year: 2015

A novel electrochemically and fluorescence active boronic ester sensor molecule has been developed containing ferrocene and naphthalimide as the redox and fluorophore units. The combinations of iron (Fe3+) ions, sodium l-ascorbate, and fluoride (F-) ions can be used to produce a molecular system displaying INHIBIT logic, due to indirect fluorescence quenching. This journal is © The Royal Society of Chemistry 2015.


Yin B.-C.,East China University of Science and Technology | Ye B.-C.,East China University of Science and Technology | Wang H.,University of Florida | Zhu Z.,University of Florida | Tan W.,University of Florida
Chemical Communications | Year: 2012

We have developed a novel molecular logic gate system based on the incorporation of aptamer-crosslinked hydrogels. Modified gold nanoparticles are used as the output signal, which is visible to the naked eye. This system is designed for AND and OR operations using two chemicals as stimulus inputs. © The Royal Society of Chemistry 2012.


Yin B.-C.,East China University of Science and Technology | You M.,University of Florida | Tan W.,University of Florida | Ye B.-C.,East China University of Science and Technology
Chemistry - A European Journal | Year: 2012

In summary, we have demonstrated a photolysis-based fluorescence turn-on sensor for the detection of Hg 2+ in aqueous solutions. Taking advantages of efficient pyrenemediate photocleavage of disulfide bonds at 350 nm irradiation, our proposed sensor delivers a detection limit of 5 nm (1 ppb), which is comparable to the most sensitive methods reported without the involvement of complicated procedures or sophisticated instrumentation. Based on the distinct advantages of high sensitivity, good selectivity and practical application, it shows that this sensor would offer an inexpensive and feasible alternative for the quantitative analysis of the Hg 2+. Moreover, we believe that this sensing design based on pyrene-disulfide molecular engineering can provide numerous applications in biomedical and proteomics scenarios, with light-induced spatio-temporal control. © 2012 Wiley-VCH Verlag GmbH&Co. KGaA, Weinheim.


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.


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.


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.


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.


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.


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.


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.


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.


Li H.,Shanghai Normal University | Zhu Z.,Shanghai Normal University | Zhang F.,Shanghai Normal University | Xie S.,Fudan University | And 2 more authors.
ACS Catalysis | Year: 2011

A hydrothermally stable metal-organic framework, MIL-101, was used as support for a metallic Pd nanoparticle catalyst. With the characterization of X-ray photoelectron spectroscopy, X-ray diffraction, N2 physisorption, scanning electron microscopy, transmission electron microscopy, and CO chemisorption, the resulting Pd nanoparticles were identified to be confined in the cages of MIL-101. During the one-pot indole synthesis between 2-iodoaniline and phenylacetylene in water, the as-prepared Pd catalyst was more active and stable than the metallic Pd nanoparticles supported on MCM-41. The enhanced catalytic properties were found to depend on both the texture and the surface chemistry of the MIL-101 support. © 2011 American Chemical Society.


Kim H.N.,Ewha Womans University | Guo Z.,East China University of Science and Technology | Zhu W.,East China University of Science and Technology | Yoon J.,Ewha Womans University | Tian H.,East China University of Science and Technology
Chemical Society Reviews | Year: 2011

Recently, fluorescent or colorimetric chemosensors based on polymers have attracted great attention due to several important advantages, such as their simplicity of use, signal amplification, easy fabrication into devices, and combination of different outputs, etc. This tutorial review will cover polymer-based optical chemosensors from 2007 to 2010. © 2011 The Royal Society of Chemistry.


Patent
East China University of Science, Technology and Shanghai Municipal Electric Power Company | Date: 2014-09-25

Disclosed is a method of measurement and determination on fracture toughness of structural materials at high temperature, comprising: preliminary assessing the ductility of a material based on a high-temperature uniaxial tensile test and the fracture characteristic; designing and manufacturing a CT specimen; conducting a monotonic loading fracture test on the CT specimen at high temperature; modifying a load-displacement curve output by a testing machine; determining a passivation coefficient M for the crack of the structural material; reversely recursing instant load-displacement data pairs corresponding to the instant crack length; calculating a J_R crack extension resistance curve of the tensile test; examining the validity of the J_R crack extension resistance curve and the fracture toughness J_(IC); calculating the fracture toughness per equivalent of the structural material K_(IC). The present invention overcomes the difficulty of placing an extensometer inside a high-temperature furnace.


News Article | December 15, 2016
Site: www.marketwired.com

TORONTO, ONTARIO--(Marketwired - Dec. 14, 2016) - Delrand Resources Limited (the "Company") (NEX:DRN.H)(TSX VENTURE:DRN.H) is pleased to announce that Zhengquan (Philip) Chen has been appointed a director of the Company. Mr. Chen is Managing Partner of Dynaco Capital Inc., a Toronto-based financial advisory firm. Philip has participated in several significant transactions between Chinese SOEs and TSX-listed mineral companies in the past two decades. He served as Executive Vice President of an affiliate of a Chinese Conglomerate in New York from March 1996 to July 1997. Mr. Chen holds an EMBA degree (University of Hawaii), LL.M degree (East China University of Science and Technology) and B.Sc. degree (Shanghai Normal University). Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.


Xiang Y.,Henan Polytechnic University | Niu Y.,East China University of Science and Technology | Gong S.,East China University of Science and Technology
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012

An intuitive physical mechanism for isolated-attosecond-pulse generation in a multicycle pulse regime is proposed. We suggest that the continuum spectra of the high-order harmonics can be controlled through the modulation of carrier wave, while keeping the multicycle envelope unchanged approximately. By increasing the time interval between the adjacent maximum return kinetic energy peaks, the kinetic energy of the side peaks will be apparently suppressed by the multicycle envelope. The photons with energies near the cutoff burst only at the pulse center with high coherence, which contribute to the generation of isolated-attosecond pulse. We verify this mechanism by using a multicycle tricolor pulse as driver field. © 2012 American Physical Society.


Cui X.,Scripps Research Institute | Gao G.,Wuhan University | Qiu Y.,East China University of Science and Technology
Biotechnology Letters | Year: 2013

Muscle-powered, biological, microelectro-mechanical system is promising for actuator and biosensor applications. Functional conjugation between the cells, tissues, and biomolecules to the microdevice is crucial for this application. Bioprinting as an enabling technology possesses the advantages of high throughput, digital control, and highly accurate delivery of various biological factors to the desired locations for numerous applications such as 3D tissue fabrication. We have now evaluated the feasibility of the precise placement of mouse myoblasts onto micro-sized cantilevers. The evenly aligned printed cells fused with each other and formed mature myotubes after only 4 days. In contrast, it took more than 14 days for randomly deposited cells to do so. The printed myotubes were functional and responded to the electrical stimulation synchronously. Furthermore, the integrated Bio-MEMS device responded to the chemical stimulation spontaneously which demonstrated the potential as a functional biosensor. The contractility of the system was recovered quickly after the removal of the chemical stimulation, which indicated the flexibility of this system and the recycling potential. © 2012 Springer Science+Business Media Dordrecht.


Xu Y.,University of Massachusetts Amherst | Mazzawi M.,University of Massachusetts Amherst | Chen K.,East China University of Science and Technology | Sun L.,University of Massachusetts Amherst | Dubin P.L.,University of Massachusetts Amherst
Biomacromolecules | Year: 2011

The effect of polyelectrolyte binding affinity on selective coacervation of proteins with the cationic polyelectrolyte, poly(diallyldimethylammonium chloride) (PDADMAC), was investigated for bovine serum albumin/β- lactoglobulin (BSA/BLG) and for the isoforms BLG-A/BLG-B. High-sensitivity turbidimetric titrations were used to define conditions of complex formation and coacervation (pHc and pHψ, respectively) as a function of ionic strength. The resultant phase boundaries, essential for the choice of conditions for selective coacervation for the chosen protein pairs, are nonmonotonic with respect to ionic strength, for both pHc and pHψ. These results are explained in the context of short-range attraction/long-range repulsion governing initial protein binding "on the wrong side of pI" and also subsequent phase separation due to charge neutralization. The stronger binding of BLG despite its higher isoelectric point, inferred from lower pHc, is shown to result from the negative "charge patch" on BLG, absent for BSA, as visualized via computer modeling (DelPhi). The higher affinity of BLG versus BSA was also confirmed by isothermal titration calorimetry (ITC). The relative values of pH ψ for the two proteins show complex salt dependence so that the choice of ionic strength determines the order of coacervation, whereas the choice of pH controls the yield of the target protein. Coacervation at I = 100 mM, pH 7, of BLG from a 1:1 (w/w) mixture with BSA was shown by SEC to provide 90% purity of BLG with a 20-fold increase in concentration. Ultrafiltration was shown to remove effectively the polymer from the target protein. The relationship between protein charge anisotropy and binding affinity and between binding affinity and selective coacervation, inferred from the results for BLG/BSA, was tested using the isoforms of BLG. Substitution of glycine in BLG-B by aspartate in BLG-A lowers pHc by 0.2, as anticipated on the basis of DelPhi modeling. The stronger binding of BLG-A, confirmed by ITC, led to a difference in pHψ that was sufficient to provide enrichment by a factor of 2 for BLG-A in the coacervate formed from "native BLG". © 2011 American Chemical Society.


Huang Y.,East China University of Science and Technology | Li Z.,East China University of Science and Technology | Shimizu K.,Kyushu Institute of Technology | Ye Q.,East China University of Science and Technology
Bioresource Technology | Year: 2012

In this study, an aldehyde dehydrogenase (ALDH) was over-expressed in Klebsiella pneumoniae for simultaneous production of 3-hydroxypropionic acid (3-HP) and 1,3-propanediol (1,3-PDO). Various genes encoding ALDH were cloned and expressed in K. pneumoniae, and expression of Escherichia coli aldH resulted in the highest 3-HP titer in anaerobic cultures in shake flasks. Anaerobic fed-batch culture of this recombinant strain was further performed in a 5-L reactor. The 3-HP concentration and yield reached 24.4g/L and 0.18mol/mol glycerol, respectively, and at the same time 1,3-PDO achieved 49.3g/L with a yield of 0.43mol/mol in 24h. The overall yield of 3-HP plus 1,3-PDO was 0.61mol/mol. Over-expression of the E. coli AldH also reduced the yields of by-products except for lactate. This study demonstrated the possibility of simultaneous production of 3-HP and 1,3-PDO by K. pneumoniae under anaerobic conditions without supply of vitamin B 12. © 2011 Elsevier Ltd.


Jiang Q.,East China University of Science and Technology | Yan X.,East China University of Science and Technology | Zhao W.,National Grid
Industrial and Engineering Chemistry Research | Year: 2013

Sensitive principal component analysis (SPCA) is proposed to improve the principal component analysis (PCA) based chemical process monitoring performance, by solving the information loss problem and reducing nondetection rates of the T2 statistic. Generally, principal components (PCs) selection in the PCA-based process monitoring is subjective, which can lead to information loss and poor monitoring performance. The SPCA method is to subsequently build a conventional PCA model based on normal samples, index PCs which reflect the dominant variation of abnormal observations, and use these sensitive PCs (SPCs) to monitor the process. Moreover, a novel fault diagnosis approach based on SPCA is also proposed due to SPCs' ability to represent the main characteristic of the fault. The case studies on the Tennessee Eastman process demonstrate the effect of SPCA on online monitoring, showing its performance is significantly better than that of the classical PCA methods. © 2013 American Chemical Society.


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.


Huang Y.,East China University of Science and Technology | Li Z.,East China University of Science and Technology | Shimizu K.,Kyushu Institute of Technology | Ye Q.,East China University of Science and Technology
Bioresource Technology | Year: 2013

Fed-batch cultures of Klebsiella pneumoniae expressing Escherichia coli aldH were performed under microaerobic conditions to investigate the effects on metabolites production. Increasing the aeration rate enhanced cell growth and 3-hydroxypropionic acid (3-HP) production, but reduced 1,3-propanediol (1,3-PDO) formation. The recombinant strain K. pneumoniae/pUC18. kan-aldHec produced 48.9. g/L of 3-HP and 25.3. g/L of 1,3-PDO with an overall yield of 0.66. mol/mol in 28. h at an aeration rate of 1.5. vvm; however, under fully aerobic condition, no 3-HP and 1,3-PDO were produced due to the repression of dha operon. The flux through the reaction catalyzed by glycerol dehydratase and the split ratio of 1,3-PDO were negatively correlated with the aeration rate, even though the 3-HP level showed a positive trend. This study demonstrated that the relative amounts of 3-HP and 1,3-PDO can be controlled by the aeration rate. © 2012 Elsevier Ltd.


Wu Y.,East China University of Science and Technology | Xie Y.,East China University of Science and Technology | Zhang Q.,East China University of Science and Technology | Tian H.,East China University of Science and Technology | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2014

Using one ray of light to encode another ray of light is highly desirable because information in optical format can be directly transferred from one beam to another without converting back to the electronic format. One key medium to accomplish such an amazing task is photoswitchable molecules. Using bis(dithiazole)ethene that can be photoswitched between its ring-open and ring-closed states quantitatively with excellent fatigue resistance and high thermal stability, it is shown that quantitative photoreversibility allowed the photoswitching light to control other light travelling through the photoswitchable medium, a phenomenon of transferring information encoded in one light ray to others, thus imparting photo-optical modulation on the orthogonal light beam. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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.


Wu S.,Hubei University | Liu X.,Hubei University | Yeung K.W.K.,University of Hong Kong | Liu C.,East China University of Science and Technology | And 2 more authors.
Materials Science and Engineering R: Reports | Year: 2014

Increased use of reconstruction procedures in orthopedics, due to trauma, tumor, deformity, degeneration and an aging population, has caused a blossom, not only in surgical advancement, but also in the development of bone implants. Traditional synthetic porous scaffolds are made of metals, polymers, ceramics or even composite biomaterials, in which the design does not consider the native structure and properties of cells and natural tissues. Thus, these synthetic scaffolds often poorly integrate with the cells and surrounding host tissue, thereby resulting in unsatisfactory surgical outcomes due to poor corrosion and wear, mechanical mismatch, unamiable surface environment, and other unfavorable properties. Musculoskeletal tissue reconstruction is the ultimate objective in orthopedic surgery. This objective can be achieved by (i) prosthesis or fixation device implantation, and (ii) tissue engineered bone scaffolds. These devices focus on the design of implants, regardless of the choice of new biomaterials. Indeed, metallic materials, e.g. 316L stainless steel, titanium alloys and cobalt chromium alloys, are predominantly used in bone surgeries, especially in the load-bearing zone of prostheses. The engineered scaffolds take biodegradability, cell biology, biomolecules and material mechanical properties into account, in which these features are ideally suited for bone tissue repair and regeneration. Therefore, the design of the scaffold is extremely important to the success of clinical outcomes in musculoskeletal surgeries. The ideal scaffolds should mimic the natural extracellular matrix (ECM) as much as possible, since the ECM found in natural tissues supports cell attachment, proliferation, and differentiation, indicating that scaffolds should consist of appropriate biochemistry and nano/micro-scale surface topographies, in order to formulate favorable binding sites to actively regulate and control cell and tissue behavior, while interacting with host cells. In addition, scaffolds should also possess a similar macro structure to what is found in natural bone. This feature may provide space for the growth of cells and new tissues, as well as for the carriers of growth factors. Another important concern is the mechanical properties of scaffolds. It has been reported that the mechanical features can significantly influence the osteointegration between implants and surrounding tissues, as well as cell behaviors. Since natural bone exhibits super-elastic biomechanical properties with a Young's modulus value in the range of 1-27 GPa, the ideal scaffolds should mimic strength, stiffness and mechanical behavior, so as to avoid possible post-operation stress shielding effects, which induce bone resorption and consequent implant failure. In addition, the rate of degradation and the by-products of biodegradable materials are also critical in the role of bone regeneration. Indeed, the mechanical integrity of a scaffold will be significantly reduced if the degradation rate is rapid, thereby resulting in a pre-matured collapse of the scaffold before the tissue is regenerated. Another concern is that the by-products upon degradation may alter the tissue microenvironment and then challenge the biocompatibility of the scaffold and the subsequent tissue repair. Therefore, these two factors should be carefully considered when designing new biomaterials for tissue regeneration. To address the aforementioned questions, an overview of the design of ideal biomimetic porous scaffolds is presented in this paper. Hence, a number of original engineering processes and techniques, including the production of a hierarchical structure on both the macro- and nano-scales, the adjustment of biomechanical properties through structural alignment and chemical components, the control of the biodegradability of the scaffold and its by-products, the change of biomimetic surface properties by altering interfacial chemistry, and micro- and nano-topographies will be discussed. In general, the concepts and techniques mentioned above provide insights into designing superior biomimetic scaffolds for bone tissue engineering. © 2014 Elsevier B.V.


Jin J.,East China University of Science and Technology | Sellers E.W.,East Tennessee State University | Wang X.,East China University of Science and Technology
Medical and Biological Engineering and Computing | Year: 2012

Longer target-to-target intervals (TTI) produce greater P300 event-related potential amplitude, which can increase brain-computer interface (BCI) classification accuracy and decrease the number of flashes needed for accurate character classification. However, longer TTIs requires more time for each trial, which will decrease the information transfer rate of BCI. In this paper, a P300 BCI using a 7 × 12 matrix explored new flash patterns (16-, 18- and 21-flash pattern) with different TTIs to assess the effects of TTI on P300 BCI performance. The new flash patterns were designed to minimize TTI, decrease repetition blindness, and examine the temporal relationship between each flash of a given stimulus by placing a minimum of one (16-flash pattern), two (18-flash pattern), or three (21-flash pattern) non-target flashes between each target flashes. Online results showed that the 16-flash pattern yielded the lowest classification accuracy among the three patterns. The results also showed that the 18-flash pattern provides a significantly higher information transfer rate (ITR) than the 21-flash pattern; both patterns provide high ITR and high accuracy for all subjects. © International Federation for Medical and Biological Engineering 2012.


Feng M.,Fuzhou University | Sun R.,Fuzhou University | Zhan H.,Fuzhou University | Chen Y.,East China University of Science and Technology
Nanotechnology | Year: 2010

The implantation and growth of metal nanoparticles on graphene nanosheets (GNS) leads directly to severe damage to the regular structure of the graphene sheets, which disrupts the extended π conjugation, resulting in an impaired device performance. In this paper, we describe a facile approach for achieving the lossless formation of graphene composite decorated with tiny cadmium sulfide quantum dots (QDs) with excellent nonlinear optical properties by using benzyl mercaptan (BM) as the interlinker. The mercapto substituent of BM binds to the CdS QDs during their nucleation and growth process, and then the phenyl comes into contact with the GNS via the π-π stacking interaction. Using this strategy, CdS QDs with an average diameter of 3nm are uniformly dispersed over the surface of graphene, and the resulting QD-graphene composite exhibits excellent optical limiting properties, mainly contributed by nonlinear scattering and nonlinear absorption, upon both 532 and 1064nm excitations, in the nanosecond laser pulse regime. © 2010 IOP Publishing Ltd.


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.


Wang H.-F.,East China University of Science and Technology | Kavanagh R.,Queen's University of Belfast | Guo Y.-L.,East China University of Science and Technology | Guo Y.,East China University of Science and Technology | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2012

Test the water: Calculations have been used to investigate why water deactivates Co 3O 4 to CO oxidation and activates platinum group metals in the same reaction. The significant difference in the potential energy surfaces of OH on metal versus metal oxides is the origin of the different effects water has in these systems. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Cheng L.-Y.,East China University of Science and Technology | Long Y.-T.,East China University of Science and Technology | Kraatz H.-B.,University of Western Ontario | Tian H.,East China University of Science and Technology
Chemical Science | Year: 2011

An immobilized artificial carbonic anhydrase model for CO2 sequestration was established by immobilizing a novel Fc-histidine conjugate on gold surfaces and then chelating with Zn2+ ions. Its catalytic activity was investigated using electrochemical and spectroscopic methods, respectively. © The Royal Society of Chemistry 2011.


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.


Wang H.-Y.,East China University of Science and Technology | Ying Y.-L.,East China University of Science and Technology | Li Y.,East China University of Science and Technology | Kraatz H.-B.,University of Western Ontario | Long Y.-T.,East China University of Science and Technology
Analytical Chemistry | Year: 2011

β-Amyloid 42 (Aβ42) is the predominant form of the amyloid peptide, which is found in the plaques of the brains of Alzheimer's (AD) patients and is one of the most abundant components in amyloid aggregates. Information of the Aβ42 aggregation states is essential for developing an understanding of the pathologic process of amyloidoses. Here, we used α-hemolysin (α-HL) pores to probe the different aggregation transition of Aβ42 in the presence of β-cyclodextrin (β-CD), a promoter of Aβ42 aggregations, and in the presence of Congo red (CR), an inhibitor of aggregations. Analyzing the characteristic transit duration times and blockade currents showed that β-CD and CR have opposite effects on the aggregation of Aβ42. Translocation events of the monomeric Aβ42 peptide were significantly lower in amplitude currents than protofilaments, and protofilaments were captured in the α-HL nanopore with a longer duration time. CR binds to Aβ42 and its peptide fibrils by reducing the aggregated fibrils formation. In this process it is assumed CR interferes with intermolecular hydrogen bonding present in the aggregates. In contrast to CR, β-CD promotes the aggregation of Aβ42. These differences can readily be analyzed by monitoring the corresponding characteristic blockade events using a biological α-HL nanopore. © 2011 American Chemical Society.


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.


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.


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.


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.


Sun J.-A.,East China University of Science and Technology | Zhang L.-Y.,Fujian Agriculture and forestry University | Rao B.,East China University of Science and Technology | Shen Y.-L.,East China University of Science and Technology | Wei D.-Z.,East China University of Science and Technology
Bioresource Technology | Year: 2012

Cofactor engineering was employed to enhance production of acetoin by Serratia marcescens H32. 2,3-Butanediol was a major byproduct of acetoin fermentation by S. marcescens H32. In order to decrease 2,3-butanediol formation and achieve a high efficiency of acetoin production, nox gene encoding a water-forming NADH oxidase from Lactobacillus brevis was expressed. Batch fermentations suggested the expression of the NADH oxidase could increase the intracellular NAD+ concentration (1.5-fold) and NAD+/NADH ratio (2.9-fold). Meanwhile, 2,3-butanediol was significantly decreased (52%), and the accumulation of acetoin was enhanced (33%) accordingly. By fed-batch culture of the engineered strain, the final acetoin titer up to 75.2g/l with the productivity of 1.88g/(lh) was obtained. To the best of our knowledge, these results were new records on acetoin fermentation ever reported. © 2012 Elsevier Ltd.


Wang Z.,Queen's University of Belfast | Cao X.-M.,East China University of Science and Technology | Zhu J.,East China University of Science and Technology | Hu P.,Queen's University of Belfast
Journal of Catalysis | Year: 2014

Dry reforming is a promising reaction to utilise the greenhouse gases CO2 and CH4. Nickel-based catalysts are the most popular catalysts for the reaction, and the coke formation on the catalysts is the main obstacle to the commercialisation of dry reforming. In this study, the whole reaction network of dry reformation on both flat and stepped nickel catalysts (Ni(1 1 1) and Ni(2 1 1)) as well as nickel carbide (flat: Ni3C(0 0 1); stepped: Ni3C(1 1 1)) is investigated using density functional theory calculations. The overall reaction energy profiles in the free energy landscape are obtained, and kinetic analyses are utilised to evaluate the activity of the four surfaces. By careful examination of our results, we find the following regarding the activity: (i) flat surfaces are more active than stepped surfaces for the dry reforming and (ii) metallic nickel catalysts are more active than those of nickel carbide, and therefore, the phase transformation from nickel to nickel carbide will reduce the activity. With respect to the coke formation, the following is found: (i) the coke formation probability can be measured by the rate ratio of CH oxidation pathway to C oxidation pathway (rCH/rC) and the barrier of CO dissociation, (ii) on Ni(1 1 1), the coke is unlikely to form, and (iii) the coke formations on the stepped surfaces of both nickel and nickel carbide can readily occur. A deactivation scheme, using which experimental results can be rationalised, is proposed. © 2014 Elsevier Inc. All rights reserved.


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.


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.


Zhang X.,East China University of Science and Technology | Zhang X.,University of Texas at Austin | You L.,University of Texas at Austin | Anslyn E.V.,University of Texas at Austin | Qian X.,East China University of Science and Technology
Chemistry - A European Journal | Year: 2012

Ginsenosides are complex natural products with a diverse array of biological activities, but their molecular recognition and sensing is challenging. A library of simple bis-boronic acid-based receptors with various spacers was synthesized for the sensing of ginsenosides. The incorporation of two boronic acids allowed the pairing of two indicators, which can simultaneously bind the receptors or two saccharides within the ginsenosides. A cross-reactive sensing array was therefore constructed using the receptors in conjunction with different pairs of indicators. LDA plots created from the colorimetric response of the hosts and indicator pairs reveal excellent classification of the ginsenosides, and the corresponding loading plots reveal the cross-reactivity of the receptors. In addition, several commercial ginseng extracts were unambiguously classified using the same sensing array. The assay reported here should be applicable to the analysis of other large saccharide-based natural products. Simplicity versus complexity: A library of simple bis-boronic acid based receptors with various spacers were synthesized and exploited for the sensing of ginsenosides, a family of complex natural products with a diverse array of biological activities. A cross-reactive sensing array was built using these receptors in conjunction with different pairs of indicators, allowing excellent differentiation and classification of the ginsenosides by means of pattern recognition protocols (see scheme). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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.


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.


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.


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.


Qian X.,East China University of Science and Technology | Xiao Y.,Dalian University of Technology | Xu Y.,East China University of Science and Technology | Guo X.,Qiqihar University | And 2 more authors.
Chemical Communications | Year: 2010

In this feature article, we report our recent progresses in fluorescent sensors of biological dyes from the viewpoint of supramolecular and bioorganic chemistry. For signalling fluorophores, we extended or created naphthalene-based ICT systems, e.g. amino-1,8-naphthalimides, amino-1,8-dicyanonaphthalenes and acenaphthopyrrol-9-carbonitriles. We also developed BODIPY derivatives with large Stokes shifts and high fluorescence quantum yields in polar solvents, and a rhodamine analogue working in strong competitive aqueous solution as well as its silaanthracene analogue with a bathochromic shift as large as 90 nm. For sensing mechanisms, we extended or developed the following methods to improve sensing: e.g. PET in a photogenerated electronic field, TICT promoted PET derived from aminoalkyl or piperazino aminonaphthalimides, and the translation/amplification effect of surfactant micelles or aggregation on fluorescent sensing. We also successfully designed deprotonation strengthened ICT, FRET-chemodosimeter sensing systems. For non-cyclic recognition receptors, naphthalimides with two or more side chains at their 4,5- or 3,4-positions, as a convenient and simple platform for ratiometric sensors, were created for the recognition of heavy and transition metallic cations; multi-armed polyamides with more side chains were innovated as a versatile platform for the sensing of metal ions with high affinity, selectivity and positive homotropic allosteric effects. We designed V-shape sensors of the bis(aminomethyl)pyridine receptor with two fluorophores to show high performance. Finally, the intracellular applications of the above sensors and dyes, e.g. imaging heavy and transition metal ions in cells, fluorescent marking of hypoxia of tumour cells, are also reviewed. © 2010 The Royal Society of Chemistry.


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.


Zhang X.,University of New Mexico | Song X.,University of New Mexico | Li H.,East China University of Science and Technology | Zhang S.,University of New Mexico | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2012

A matter of protection: The outcome of a divergent organocatalytic aza-Michael/aldol cascade process toward quinolines and 1,4-dihydroquinolines depends on the choice of the N-protecting group (see scheme; TEA=triethylamine, TMS=trimethylsilyl). Use of an electron-donating sulfonyl group results in an unanticipated aza-Michael/aldol/aromatization cascade to give polysubstituted quinolines (right). In contrast, chiral 1,4-dihydroquinolines are obtained with an electron-withdrawing sulfonyl group (left). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Sun D.,East China University of Science and Technology | Sun D.,Changchun University of Technology | Li B.-B.,Changchun University of Technology | Xu Z.-L.,East China University of Science and Technology
Desalination | Year: 2013

A novel organophilic nano-silica (ONS) filled polydimethylsiloxane (PDMS) composite membrane was prepared and characterized for the pervaporation (PV) of ethanol from water. The sorption and diffusion behaviors of ethanol and water in the composite membranes were investigated. The results showed that with increasing ONS concentration from 0wt.% to 10wt.%, the solubility selectivity and the diffusion selectivity increased from 21.87 to 38.85 and from 1.87 to 6.18, respectively. When the temperature ranged from 30°C to 70°C, the solubility selectivity increased but the diffusion selectivity first increased and then decreased. The effects of ONS content, feed temperature and permeate-side vacuum on the PV performance of the composite membrane for the pervaporation of 5 wt.% ethanol-water mixture were studied. The examinations showed that the composite membranes exhibited striking advantages in total flux and separation factor as compared with unfilled PDMS membrane. When ONS loading was 5 wt.%, the PDMS composite membrane showed the best PV performances with the permeate flux (J) of 114g/(m2·h), the separation factor (α) of 30.1 and permeate separate index (PSI), of 3420, respectively. With an increase of the feed temperature from 30 to 70°C, the total flux of filled PDMS membrane with 5 wt.% ONS increased apparently from 11.1 to 210g/(m2·h), and the maximum separation factor of 30.1 was observed at 60°C. With an increase of vacuum in permeate-side from 0.075 to 0.100MPa, both separation factor and total flux increased for filled PDMS membrane with 5 wt.% ONS. © 2013 Elsevier B.V.


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).


Saidalimu I.,East China University of Science and Technology | Fang X.,East China University of Science and Technology | He X.-P.,East China University of Science and Technology | Liang J.,East China University of Science and Technology | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2013

An organocatalytic asymmetric direct aldol addition reaction that involves cleavage of a carbon-carbon bond through the release of trifluoroacetate was developed. The protocol is wide in scope, generating the desired oxindoles of biological interest in nearly quantitative yields (up to 99 %) with excellent enantioselectivities (up to 98 % ee) and diastereoselectivities (up to 99:1 d.r.). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu W.,East China University of Science and Technology | Wang Y.,East China University of Science and Technology | Yu Z.,Petrochina | Bao J.,East China University of Science and Technology
Bioresource Technology | Year: 2012

Simultaneous saccharification and fermentation (SSF) is the most commonly practiced operation in lignocellulose bioconversion to avoid the sugar product inhibition to cellulase enzymes. In this study, for the first time SSF was tested on microbial lipid fermentation using the diluted acid pretreated and biodetoxified corn stover. The results show that SSF was effective than the separate hydrolysis and fermentation (SHF) on lipid accumulation of Trichosporon cutaneum CX1 cells in both the small scale (5. L) and the enlarged scale (50. L) bioreactors. The solutions for the oxygen transfer and the lipid extraction in SSF practically worked well. The process parameters were optimized and the lipid yield obtained were 3.03. g/L in the 5. L, and 3.23. g/L in the 50. L, respectively. The result also shows that the cellulase enzyme could be partially recycled in the SSF. The study provided a practical and efficient way for microbial lipid production from lignocellulose material. © 2012 Elsevier Ltd.


Wei P.-J.,East China University of Science and Technology | Yu G.-Q.,East China University of Science and Technology | Naruta Y.,Chubu University | Liu J.-G.,East China University of Science and Technology
Angewandte Chemie - International Edition | Year: 2014

The oxygen reduction reaction (ORR) is one of the most important reactions in both life processes and energy conversion systems. The replacement of noble-metal Pt-based ORR electrocatalysts by nonprecious-metal catalysts is crucial for the large-scale commercialization of automotive fuel cells. Inspired by the mechanisms of dioxygen activation by metalloenzymes, herein we report a structurally well-defined, bio-inspired ORR catalyst that consists of a biomimetic model compound - an axial imidazole-coordinated porphyrin - covalently attached to multiwalled carbon nanotubes. Without pyrolysis, this bio-inspired electrocatalyst demonstrates superior ORR activity and stability compared to those of the state-of-the-art Pt/C catalyst in both acidic and alkaline solutions, thus making it a promising alternative as an ORR electrocatalyst for application in fuel-cell technology. Bio-inspired catalyst defeats Pt: A biomimetic electrocatalyst for the oxygen reduction reaction (ORR) has been covalently grafted onto multiwalled carbon nanotubes. Without pyrolysis, this bio-inspired catalyst, in which an axial imidazole-coordinated porphyrin mimics the active site of O2-activating heme-containing enzymes, shows superior ORR activity and stability compared to the state-of-the-art Pt/C catalyst in both acidic and alkaline solutions. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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.


Nie M.,East China University of Science and Technology | Zou Y.C.,East China University of Science and Technology | Huang Y.M.,East China University of Science and Technology | Wang J.Q.,CAS Shanghai Institute of Applied Physics
International Journal of Hydrogen Energy | Year: 2012

A series of Ni-Fe-B catalysts with different Fe/(Fe + Ni) molar ratios, used for the hydrolysis of NaBH4, were prepared by chemical reduction of NiCl2 and FeCl3 mixed solution with NaBH4. The measurements revealed that the catalysts with the molar ratio of Fe/(Fe + Ni) (30%) exhibited the highest catalytic activity, and the optimal reduction temperature is 348 K. In addition, the effects of the concentration of NaBH 4, NaOH and the hydrolytic temperature of NaBH4 were discussed in detail. The results show that the reaction rate of hydrolysis first rises up and then goes down subsequently with the increase of NaBH4 concentration, as well as the concentration of NaOH. The activation energy of the hydrolysis for Ni-Fe-B catalysts is fitted to 57 kJ/mol. The maximum value of hydrogen generation is 2910 ml/(min g) at 298 K. © 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.


Yuan Z.,Dalian University of Technology | Xiao Y.,Dalian University of Technology | Xiao Y.,East China University of Science and Technology | Qian X.,East China University of Science and Technology
Chemical Communications | Year: 2010

By photocyclization, benzene, thieno[3,2-b]thiophene, and fluorene units were embedded between the two perylene units. Symmetric oligomeric perylene bisimide 6 displays broad absorption and strong electron-accepting ability. © 2010 The Royal Society of Chemistry.


Yang F.,East China University of Science and Technology | Wang J.,East China University of Science and Technology | Hou J.,East China University of Science and Technology | Guo H.,CAS Shanghai Institute of Applied Physics | Liu C.,East China University of Science and Technology
Biomaterials | Year: 2013

The treatment of large osseous defects remains a challenging clinical problem in orthopedic surgery. Particularly, strategies to control the appropriate degradation rate adapting to the tissue reconstruction are of essential for tissue regeneration. Here we report on a strategy to achieve adaptive degradation rate using cell-secreted protease as a switch. Disulfide-containing PEG-based scaffolds have been synthesized, and demonstrated to be responsive to the cell-secreted redox microenvironment. Thus, the cell-triggered degradation and liberation of growth factor are achieved. The osteoinductive growth factor, recombinant human bone morphogenetic protein-2 (rhBMP-2), is incorporated into the scaffold for bioactivity promotion. Degradations under the stimuli of reduced glutathione (GSH) at intracellular and extracellular concentrations was studied with the results of duration time ranging from 0.5 h to 22 days regulated by both concentrations of redox medium and polymer precursors. The rhBMP-2 loaded scaffolds evidently induced the ectopic bone formation in the mouse thigh muscles. In addition, we further investigated the in vivo effects of rhBMP-2-loaded scaffolds in a rabbit radius critical defect by radiography, three dimensional micro-computed tomographic (μCT) and synchrotron radiation-based micro-computed tomography (SR. μCT) imaging, histological analysis, and biomechanical measurement. Scaffolds underwent gradual resorption and replacement by new bone and induced reunion of bone marrow cavity at 12 weeks, much better than the effect of self-repairing group. The results indicated that both osteoinduction and appropriate degradation played a crucial role in accelerating and promoting bone augmentation, as well as effective proangiogenesis. Such a strategy appears promising as 3D temporal scaffolds for potential orthopedic applications. © 2012 Elsevier Ltd.


Xie H.,University of New Mexico | Zhang Y.,University of New Mexico | Zhang S.,University of New Mexico | Zhang S.,East China University of Science and Technology | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2011

Highly efficient: The title reaction provides biologically interesting chiral trifluoromethyl dihydroquinazolinone frameworks in high yields (up to 97%) and with high enantioselectivities (up to 98% ee), using as low as 1 mol% of catalyst (see scheme). Moreover, anti-HIV drug candidate DPC 083 was efficiently synthesized using the highly enantioselective aza-Henry reaction as a key step. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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).


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.


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.


Yang F.,East China University of Science and Technology | Yang F.,Brunel University | Li Y.,Brunel University
IEEE Transactions on Systems, Man, and Cybernetics, Part B: Cybernetics | Year: 2010

This paper is concerned with the set-membership filtering (SMF) problem for discrete-time nonlinear systems. We employ the Takagi-Sugeno (T-S) fuzzy model to approximate the nonlinear systems over the true value of state and to overcome the difficulty with the linearization over a state estimate set rather than a state estimate point in the set-membership framework. Based on the T-S fuzzy model, we develop a new nonlinear SMF estimation method by using the fuzzy modeling approach and the S-procedure technique to determine a state estimation ellipsoid that is a set of states compatible with the measurements, the unknown-but-bounded process and measurement noises, and the modeling approximation errors. A recursive algorithm is derived for computing the ellipsoid that guarantees to contain the true state. A smallest possible estimate set is recursively computed by solving the semidefinite programming problem. An illustrative example shows the effectiveness of the proposed method for a class of discrete-time nonlinear systems via fuzzy switch. © 2009 IEEE.


Zuo P.,University of Texas at El Paso | Li X.,University of Texas at El Paso | Li X.,East China University of Science and Technology | Dominguez D.C.,University of Texas at El Paso | Ye B.-C.,East China University of Science and Technology
Lab on a Chip - Miniaturisation for Chemistry and Biology | Year: 2013

Infectious pathogens often cause serious public health concerns throughout the world. There is an increasing demand for simple, rapid and sensitive approaches for multiplexed pathogen detection. In this paper we have developed a polydimethylsiloxane (PDMS)/paper/glass hybrid microfluidic system integrated with aptamer-functionalized graphene oxide (GO) nano-biosensors for simple, one-step, multiplexed pathogen detection. The paper substrate used in this hybrid microfluidic system facilitated the integration of aptamer biosensors on the microfluidic biochip, and avoided complicated surface treatment and aptamer probe immobilization in a PDMS or glass-only microfluidic system. Lactobacillus acidophilus was used as a bacterium model to develop the microfluidic platform with a detection limit of 11.0 cfu mL-1. We have also successfully extended this method to the simultaneous detection of two infectious pathogens - Staphylococcus aureus and Salmonella enterica. This method is simple and fast. The one-step 'turn on' pathogen assay in a ready-to-use microfluidic device only takes ∼10 min to complete on the biochip. Furthermore, this microfluidic device has great potential in rapid detection of a wide variety of different other bacterial and viral pathogens. © 2013 The Royal Society of Chemistry.


Song D.-M.,East China University of Science and Technology | Tumminello M.,Carnegie Mellon University | Tumminello M.,University of Palermo | Zhou W.-X.,East China University of Science and Technology | Mantegna R.N.,University of Palermo
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2011

We investigate the daily correlation present among market indices of stock exchanges located all over the world in the time period January 1996 to July 2009. We discover that the correlation among market indices presents both a fast and a slow dynamics. The slow dynamics reflects the development and consolidation of globalization. The fast dynamics is associated with critical events that originate in a specific country or region of the world and rapidly affect the global system. We provide evidence that the short term time scale of correlation among market indices is less than 3 trading months (about 60 trading days). The average values of the nondiagonal elements of the correlation matrix, correlation-based graphs, and the spectral properties of the largest eigenvalues and eigenvectors of the correlation matrix are carrying information about the fast and slow dynamics of the correlation of market indices. We introduce a measure of mutual information based on link co-occurrence in networks in order to detect the fast dynamics of successive changes of correlation-based graphs in a quantitative way. © 2011 American Physical Society.


Zhao L.,Fudan University | Peng J.,Fudan University | Huang Q.,East China University of Science and Technology | Li C.,Fudan University | And 5 more authors.
Advanced Functional Materials | Year: 2014

Phototrigger-controlled drug-release devices (PDDs) can be conveniently manipulated by light to obtain on-demand release patterns, thereby affording an improved therapeutic efficacy. However, no example of the PDDs has been demonstrated beyond the cellular level to date. By loading 7-amino-coumarin derivative caged anticancer drug chlorambucil to yolk-shell structured nanocages possessing upconversion nanophosphors (UCNPs) as moveable core and silica as mesoporous shell, a near-infrared (NIR)-regulated PDD is successfully created. In vitro experiments demonstrate that drug release from the PDD could be triggered by continuous-wave 980 nm light in a controlled pattern. The PDD could be taken up by cancer cells and release the drug to kill cancer cells upon NIR irradiation. Further in vivo studies demonstrate that the PDD can effectively response the NIR stimuli in living tissue. This is the first example of successful NIR-regulated drug release in living animal model. Such achievement resolves the problem of low tissue penetration depth for traditional PDDs by adopting UCNPs as an NIR light switcher, which gives impetus to practical applications. A near-infrared (NIR) phototrigger-controlled drug-release device (PDD) is designed using yolk-shell structured nanocages with upconversion nanophosphors as yolks and silica as shells (YSUCNP). The anticancer drug chlorambucil caged with a coumarin phototrigger is accommodated by YSUCNPs to a large loading capacity of 49 wt%. By employing NIR light with deep tissue penetration depth as stimuli, the PDD demonstrates efficacy in living tumor-bearing mice with zero premature release. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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.


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.


Qian X.,East China University of Science and Technology | Xu Z.,CAS Dalian Institute of Chemical Physics
Chemical Society Reviews | Year: 2015

Metal ions play an important role in various biological processes, their abnormal homeostasis in cells is related to many diseases, such as neurodegenerative disease, cancer and diabetes. Fluorescent imaging offers a unique route to detect metal ions in cells via a contactless and damage-free way with high spatial and temporal fidelity. Consequently, it represents a promising method to advance the understanding of physiological and pathological functions of metal ions in cell biology. In this highlight article, we will discuss recent advances in fluorescent imaging of metal ions by small-molecule sensors for understanding the role of metals in related diseases. We will also discuss challenges and opportunities for the design of small-molecule sensors for fluorescent detection of cellular metal ions as a potential method for disease diagnosis. This journal is © The Royal Society of Chemistry 2015.


Zhu W.,East China University of Science and Technology | Wu Y.,East China University of Science and Technology | Wang S.,Fudan University | Li W.,East China University of Science and Technology | And 4 more authors.
Advanced Functional Materials | Year: 2011

A novel concept "D-A-π-A" organic sensitizer instead of traditional D-π-A ones is proposed. Remarkably, the incorporated low bandgap, strong electron-withdrawing unit of benzothiadiazole shows several favorable characteristics in the areas of light-harvesting and efficiency: i) optimized energy levels, resulting in a large responsive range of wavelengths into NIR region; ii) a very small blue-shift in the absorption peak on thin TiO 2 films with respect to that in solution; iii) an improvement in the electron distribution of the donor unit to distinctly increase the photo-stability of synthetic intermediates and final sensitizers. The stability and spectral response of indoline dye-based DSSCs are improved by the strong electron-withdrawing benzothiadizole unit in the conjugation bridge. The incident-photon-conversion efficiency of WS-2 reaches nearly 850 nm with a power conversion efficiency as high as 8.7% in liquid electrolyte and 6.6% in ionic-liquid electrolyte. Four D-A-π-A configuration organic dyes containing benzothiadiazole are developed for dye-sensitized solar cells (DSSCs). The stability and spectral response of indoline dye-based DSSCs are improved by the strong electron-withdrawing benzothiadiazole unit in the conjugation bridge. The incident-photon-conversion efficiency of WS-2 reaches nearly 850 nm with power conversion efficiency as high as 8.7% in liquid electrolyte and 6.6% in ionic-liquid electrolyte. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wu Y.,East China University of Science and Technology | Zhang X.,Fudan University | Li W.,East China University of Science and Technology | Wang Z.-S.,Fudan University | And 2 more authors.
Advanced Energy Materials | Year: 2012

For a sensitizer with a strong π-conjugation system, a coadsorbent is needed to hinder dye aggregation. However, coadsorption always brings a decrease in dye coverage on the TiO 2 surface. Organic "D-A-π-A" dyes, WS-6 and WS-11, are designed and synthesized based on the known WS-2 material for coadsorbent-free, dye-sensitized solar cells (DSSCs). Compared with the traditional D-π-A structure, these D-A-π-A indoline dyes, with the additional incorporated acceptor unit of benzothiadiazole in the π-conjugation, exhibit a broad photoresponse, high redox stability, and convenient energy-level tuning. The attached n-hexyl chains in both dyes are effective to suppress charge recombination, resulting in a decreased dark current and enhanced open-circuit voltage. Electrochemical impedance spectroscopy studies indicate that both the resistance for charge recombination and the electron lifetime are increased after the introduction of alkyl chains to the dye molecules. Without deoxycholic acid coadsorption, the power-conversion efficiency of WS-6 (7.76%) on a 16 μm-thick TiO 2 film device is 45% higher than that of WS-2 (5.31%) under the same conditions. The additional n-hexylthiophene in WS-11 extends the photoresponse to a panchromatic spectrum but causes a low incident photon-to-current conversion efficiency. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Yan Y.,East China University of Science and Technology | Cheng Q.,East China University of Science and Technology | Cheng Q.,Tomas Bata University in Zlin | Wang G.,East China University of Science and Technology | Li C.,East China University of Science and Technology
Journal of Power Sources | Year: 2011

Vertically aligned polyaniline nanowhiskers (PANI-NWs) doped with (1R)-(-)-10-Camphorsulfonic acid (L-CSA) have been successfully synthesized on the external surface of ordered mesoporous carbon (CMK-3) by chemical oxidative polymerization. The specific surface area of the PANI-NWs/CMK-3 nanocomposite remains as high as 497 m2 g-1 by removing mesoporous silica template after the polymerization of aniline. Structural and morphological characterizations of the nanocomposite were further investigated by XRD, FTIR and FE-SEM measurements. The result shows that the nanocomposite with 40 wt% PANI applying in supercapacitor devices possesses a large specific capacitance of 470 F g-1 and good capacitance retention of 90.4% is achieved after 1000 cycles at a current density of 1.0 A g-1. The synergistic effect of small PANI nanowhisker arrays and well-ordered mesoporous carbon endows the composite with high electrochemical capacitance and good cycling stability. © 2010 Elsevier B.V. All rights reserved.


Lu X.,East China University of Science and Technology | Guo Z.,East China University of Science and Technology | Feng M.,Fudan University | Zhu W.,East China University of Science and Technology
ACS Applied Materials and Interfaces | Year: 2012

A Hg 2+ chemodosimeter P3 derived from a perylenebisimide scaffold and thiourea fragments was systematically studied with focus on the photophysical, chemodosimetric mechanistic, as well as fluorogenic behaviors toward various metal cations for the sake of improving selectivity to Hg 2+. As demonstrated, Hg 2+ can promote a stepwise desulfurization and N-acylation of P3 with the help of an acetate anion (OAc -), resulting in an N-acylated urea derivative. Interestingly, OAc - has the effect of improving the selectivity of P3 to Hg 2+ among other metal ions; that is, in an acetone/Britton-Robinson buffer (9:1, v/v; pH 7.0) upon excitation at 540 nm, the relative fluorescence intensity is increased linearly with increasing concentration of Hg 2+ in the range of 2.5-20 μM with a detection limit of 0.6 μM, whereas the fluorescence intensity of P3 to other metal ions, including Na +, K +, Mg 2+, Ca 2+, Mn 2+, Fe 2+, Ni 2+, Co 2+, Zn 2+ Ag +, Cd 2+, Pb 2+, and Cu 2+, is negligible. The fluorescent bioimaging of chemodosimeter P3 to detect Hg 2+ in living cells was also reported. © 2012 American Chemical Society.


Wu S.,East China University of Science and Technology | Dzubiella J.,Helmholtz Center Berlin | Dzubiella J.,Humboldt University of Berlin | Kaiser J.,Helmholtz Center Berlin | And 7 more authors.
Angewandte Chemie - International Edition | Year: 2012

Selectivity in nanoreactors: A hybrid yolk-shell nanostructure that contains gold nanoparticles in the core and thermosensitive microgel poly(N-isopropylacrylamide) (PNIPA) as shell is presented. The catalytic selectivity of Au-PNIPA nanoparticles for the reduction of hydrophilic 4-nitrophenol and more hydrophobic nitrobenzene with NaBH 4 can be tuned through the volume transition of PNIPA shell (see picture). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Lin Q.,East China University of Science and Technology | Huang Q.,East China University of Science and Technology | Li C.,Fudan University | Bao C.,East China University of Science and Technology | And 3 more authors.
Journal of the American Chemical Society | Year: 2010

An excellent mesoporous silica nanoparticle (MSN) based drug deliver system (DDS) was reported for regulated anticancer drug release upon the irradiation of either one- or two-photon excitation. In this system, the coumarin grafted on MSN acted as both the "phototrigger" for the drug release and fluorescence group for cell luminescence imaging. External light manipulations such as changing irradiation wavelength, intensity, and time can regulate the release of the anticancer drug precisely. Biological studies in vitro suggest that the drug carrier can effectively deliver the anticancer drug into intracellular environs and, hence, promote the drug action to kill the cancer cells upon irradiation. We envision that the good biocompatibility, cellar uptake property, and efficient photoregulated drug release will be of great benefit to future controlled release in vivo biomedical applications. © 2010 American Chemical Society.


Zhou G.-Y.,East China University of Science and Technology | Wu E.,Jinling Institute of Technology | Tu S.-T.,East China University of Science and Technology
Applied Energy | Year: 2014

Heat exchangers are the typical products of the process equipment, which have been playing an important role in process engineering. With the increase of awareness of energy shortage, saving energy and reducing waste have become the major principle of industrial production. The key to develop the energy saving technology has been the design of the optimal heat exchangers with the best comprehensive performance adapted to the different working conditions. It is thus of urgent need to develop the related design methodology and evaluation system. Because of the difficulties met in conception design of compact heat exchangers, a multi-level, multi-factor and non-structural fuzzy optimum decision model is used in the optimal selection of compact heat exchangers. A three-level fuzzy optimum decision is introduced with success to cover most of the effective factors and determine the optimal design projects, which includes six design projects and eight influencing factors. © 2013 Elsevier Ltd.


Liu Z.,East China University of Science and Technology | Lin Q.,East China University of Science and Technology | Sun Y.,Fudan University | Liu T.,East China University of Science and Technology | And 3 more authors.
Advanced Materials | Year: 2014

A new concept of photocrosslinking mechanism is developed to construct a 3D cell culture matrix based on a photo-uncaged-thiol Michael addition. This first-class approach not only provides highly cytocompatible gelation in a spatiotemporally controlled manner, but also controls gel stiffness via appropriate light dose, signaling desired cues to live cells and thus important to bioengineering and regenerative medicine. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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.


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.


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.


Ding Y.,East China University of Science and Technology | Ding Y.,Nanjing University | Tang Y.,East China University of Science and Technology | Zhu W.,East China University of Science and Technology | Xie Y.,East China University of Science and Technology
Chemical Society Reviews | Year: 2015

Metal ions and anions play important roles in many industrial and biochemical processes, and thus it is highly desired to detect them in the relevant systems. Small organic molecule based sensors for selective and sensitive detection of target ions show the advantages of low cost, high sensitivity and convenient implementation. In this area, pyrrole has incomparable advantages. It can be easily incorporated into linear and macrocyclic conjugated structures such as dipyrrins, porphyrins, and N-confused porphyrins, which may utilize the imino N and amino NH moieties for binding metal ions and anions, respectively. In this tutorial review, we focus on representative examples to describe the design, syntheses, sensing mechanisms, and applications of the conjugated oligopyrroles. These compounds could be used as colorimetric or fluorescent ion probes, with the advantages of vivid colour and fluorescence changes, easy structural modification and functionalization, and tunable emission wavelengths. Compared with normal porphyrins, simple di- and tripyrrins, as well as some porphyrinoids are more suitable for designing fluorescence "turn-on" metal probes, because they may exhibit flexible confirmations, and metal coordination will improve the rigidity, resulting in vivid fluorescence enhancement. It is noteworthy that the oligopyrrolic moieties may simultaneously act as the binding unit as well as the reporting moiety, which simplifies the design and syntheses of the probes. This journal is © The Royal Society of Chemistry.


Jiang H.,East China University of Science and Technology | Hu Y.,East China University of Science and Technology | Guo S.,Los Alamos National Laboratory | Yan C.,Nanyang Technological University | And 2 more authors.
ACS Nano | Year: 2014

Searching the long-life MnO-based materials for lithium ion batteries (LIBs) is still a great challenge because of the issue related to the volumetric expansion of MnO nanoparticles (NPs) or nanowires (NWs) during lithiation. Herein, we demonstrate an unexpected result that a peapod-like MnO/C heterostructure with internal void space can be facilely prepared by annealing the MnO precursor (MnO-P) NW/polydopamine core/shell nanostructure in an inert gas, which is very different from the preparation of typical MnO/C core/shell NWs through annealing MnO NW/C precursor nanostructure. Such peapod-like MnO/C heterostructure with internal void space is highly particular for high-performance LIBs, which can address all the issues related to MnO dissolution, conversion, aggregation and volumetric expansion during the Li + insertion/extraction. They are highly stable anode material for LIBs with a very high reversible capacity (as high as 1119 mAh g-1 at even 500 mA g-1) and fast charge and discharge capability (463 mAh g-1 at 5000 mA g-1), which is much better than MnO NWs (38 mAh g-1 at 5000 mA g-1) and MnO/C core/shell NWs (289 mAh g-1 at 5000 mA g-1). Such nanopeapods also show excellent rate capability (charged to 91.6% in 10.6 min using the constant current mode). Most importantly, we found that MnO/C nanopeapods show no capacity fading even after 1000 cycles at a high current density of 2000 mA g-1, and no morphology change. The present MnO/C nanopeapods are the most efficient MnO-based anode materials ever reported for LIBs. © 2014 American Chemical Society.


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.


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.


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.


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.


Yan H.,East China University of Science and Technology | Su Z.,East China University of Science and Technology | Zhang H.,City University of Hong Kong | Zhang H.,Tongji University | Yang F.,East China University of Science and Technology
IET Control Theory and Applications | Year: 2013

In this study, the authors are concerned with the observer-based quantised H∞ control problem for a class of discretetime stochastic systems with random communication delays. The system under consideration involves signals quantisation, statedependent disturbance as well as random communication delays. The measured output and the control input quantisation are considered simultaneously by using the sector bound approach, while the random communication delays from the sensor to the controller and from the controller to the plant are modelled by a linear function of the stochastic variable satisfying Bernoulli random binary distribution. It is aimed at designing an observer-based controller such that the dynamics of the closed-loop system is guaranteed to be exponentially stable in the mean square, and a prescribed H∞ disturbance attenuation level is also achieved. Finally, a simulation example is given to illustrate the effectiveness of the proposed method. © The Institution of Engineering and Technology 2013.


Yu W.-G.,East China University of Science and Technology | Qian J.,Tongji University | Lu Y.-H.,East China University of Science and Technology
Journal of Agricultural and Food Chemistry | Year: 2011

In this paper, the hepatoprotective effects of 2′,4′-dihydroxy- 6′-methoxy-3′,5′-dimethylchalcone (DMC) on CCl 4-induced acute liver injury in Kunming mice were investigated. DMC was administered intraperitoneally (ip) (5, 10, or 20 mg/kg of body weight) for 7 days prior to the administration of CCl 4 (0.1%, ip). Pretreatment with DMC significantly decreased activities of serum hepatic enzymes, namely alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, alkaline phosphatase, γ-glutamyl transferase, and total bilirubin, and decreased the elevation of lipid peroxidation, malondialdehyde, reactive oxygen species, and protein carbonyl content. Pretreatment with DMC markedly increased activities of enzymatic antioxidants such as superoxide dismutase, catalase, glucose-6-phosphate dehydrogenase, glutathione peroxidase, glutathione S-transferase, and glutathione reductase and increased levels of nonenzymatic antioxidant markers such as reduced glutathione, total sulfhydryl groups, vitamin C, and vitamin E in liver. These results combined with liver histopathology demonstrate that DMC has potential hepatoprotective effects, which may be related to the attenuation of oxidative stress, accelerating the antioxidant cascade and inhibition of lipid peroxidation. © 2011 American Chemical Society.


Sun Q.,Tongji University | Zhang C.,Tongji University | Li Z.,East China University of Science and Technology | Kong H.,Tongji University | And 3 more authors.
Journal of the American Chemical Society | Year: 2013

On-surface fabrication of covalently interlinked conjugated nanostructures has attracted significant attention, mainly because of the high stability and efficient electron transport ability of these structures. Here, from the interplay of scanning tunneling microscopy imaging and density functional theory calculations, we report for the first time on-surface formation of one-dimensional polyphenylene chains through Bergman cyclization followed by radical polymerization on Cu(110). The formed surface nanostructures were further corroborated by the results for the ex situ-synthesized molecular product after Bergman cyclization. These findings are of particular interest and importance for the construction of molecular electronic nanodevices on surfaces. © 2013 American Chemical Society.


Liu H.,East China University of Science and Technology | Li C.,East China University of Science and Technology | Qiu D.,CAS Beijing National Laboratory for Molecular | Tong X.,East China University of Science and Technology
Journal of the American Chemical Society | Year: 2011

A palladium-catalyzed iodine atom transfer cycloisomerization of (Z)-1-iodo-1,6-diene has been developed, which provides a facile method to construct six-memebered heterocycles bearing an alkyl iodide group. The ligand screening shows that both the type and the quantity of ligand impose significant influences on this transformation, and the combination of 30 mol % 1,1′-bis(diphenylphosphino)ferrocene (DPPF) and 10 mol % Pd(OAc) 2 is the optimal choice. The catalytic cycle, consisting of oxidative addition of Pd(0) to vinyl iodide, intramolecular alkene insertion, and alkyl iodide reductive elimination, has been proposed and eventually supported by convincing evidence from a series of control experiments. More importantly, these control experiments disclose some features of the event of alkyl iodide reductive elimination: (1) this reductive elimination is proved to be a stereospecific process; and (2) both alkyl iodide oxidative addition and reductive elimination are not effected by a TEMPO additive. Besides its ability to undergo oxidative addition, the catalyst (palladium + DPPF) could also promote a radical transfer process. The findings described in this paper will be helpful for further development of the metal-catalyzed formation of a carbon-halide bond. © 2011 American Chemical Society.


Li W.,East China University of Science and Technology | Jiao C.,East China University of Science and Technology | Li X.,East China University of Science and Technology | Xie Y.,East China University of Science and Technology | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2014

Endowing both solvent independency and excellent thermal bistability, the benzobis(thiadiazole)-bridged diarylethene system provides an efficient approach to realize extremely high photocyclization quantum yields (Φo-c, up to 90.6 %) by both separating completely pure anti-parallel conformer and suppressing intramolecular charge transfer (ICT). Large hindrance, high efficiency: A novel benzobis(thiadiazole)-bridged diarylethene system shows excellent thermal bistability and extremely high, solvent-independent photocyclization quantum yields (Φo-c, up to 90.6 %). It is characterized by a complete separation of the anti-parallel conformer and the suppression of intramolecular charge transfer (ICT). EWG=electron-withdrawing group. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Ma W.,East China University of Science and Technology | Li D.-W.,East China University of Science and Technology | Sutherland T.C.,University of Calgary | Li Y.,East China University of Science and Technology | And 2 more authors.
Journal of the American Chemical Society | Year: 2011

Here, we report the reversible interconversion between NADH and NAD + at a low overpotential, which is in part mediated by ubiquinone embedded in a biomimetic membrane to mimic the initial stages of respiration. This system can be used as a platform to examine biologically relevant electroactive molecules embedded in a natural membrane environment and provide new insights into the mechanism of biological redox cycling. © 2011 American Chemical Society.


Ren F.,East China University of Science and Technology | Zhong L.-X.,Zhejiang University of Finance and Economics
Physica A: Statistical Mechanics and its Applications | Year: 2012

The asymmetric price impact between the institutional purchases and sales of 32 liquid stocks in the Chinese stock market in 2003 is carefully studied. We analyze the price impact in both drawup and drawdown trends with consecutive positive and negative daily price changes, and test the dependence of the price impact asymmetry on the market condition. For most of the stocks, institutional sales have a larger price impact than institutional purchases, and a larger impact of institutional purchases exists only in a few stocks with primarily increasing tendencies. We further study the mean return of trades surrounding institutional transactions, and find that the asymmetric behavior also exists before and after institutional transactions. A new variable is proposed to investigate the order book structure, and it can partially explain the price impact of institutional transactions. A linear regression for the price impact of institutional transactions further confirms our finding that institutional sales primarily have a larger price impact than institutional purchases in the bearish year 2003. © 2011 Elsevier B.V. All rights reserved.


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.


Zhang H.,Tongji University | Yan H.,East China University of Science and Technology | Yang F.,East China University of Science and Technology | Chen Q.,Tongji University
IEEE Transactions on Fuzzy Systems | Year: 2011

In this paper, a continuous-time Takagi-Sugeno (T-S) fuzzy system with impulsive effects that are controlled through network is investigated. Network signal-transmission delays and signal-quantization effects are simultaneously considered. The network is with two time-varying additive delays and limited capacity. First, a quantized output-feedback networked control system (NCS) model is established to describe the impulsive NCSs through a channel with limited capacity. Then, based on the Lyapunov-Krasovskii functional approach and a parallel-distributed compensation scheme, a delay-dependent stabilization approach is developed for the impulsive NCSs, which guarantees that the closed-loop system is asymptotically stable. Finally, a simulation example is given to illustrate the effectiveness of the proposed method. © 2011 IEEE.


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.


Zhao Q.-Y.,East China University of Science and Technology | Huang L.,East China University of Science and Technology | 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
Advanced Synthesis and Catalysis | Year: 2012

The first example of a β-isocupreidine (β-ICD)-catalyzed highly enantioselective [2+2] annulation of allenoates with trifluoromethyl ketones has been disclosed, allowing the synthesis of optically active 2-alkyleneoxetanes in moderate to good yields along with good to high enantioselectivities and high diastereoselectivities. Further transformations of the cycloadducts have been also disclosed to afford biologically interesting 6-trifluoromethyl-5,6- dihydropyran-2-ones and trifluoromethyl β-keto acids in good yields. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Du D.,East China University of Science and Technology | Jiang Y.,East China University of Science and Technology | Xu Q.,CAS Shanghai Institute of Organic Chemistry | Shi M.,East China University of Science and Technology | Shi M.,CAS Shanghai Institute of Organic Chemistry
Advanced Synthesis and Catalysis | Year: 2013

A novel Cinchona alkaloid-derived organocatalyst having stronger hydrogen-bonding donors that catalyzes the asymmetric [3+2] cycloaddition of 3-isothiocyanatooxindoles with allenic esters or 2-butynedioic acid diesters has been developed, affording functionalized spirooxindole derivatives in high yields along with good to excellent enantioselectivities under mild conditions. We also found that by changing the ratio of the substrates, different spirooxindole derivatives could be obtained in high yields along with good to excellent enantioselectivities. © 2013 Wiley-VCH Verlag GmbH&Co. KGaA, Weinheim.


Gao X.,East China University of Science and Technology | Gao X.,CAS Shanghai Institute of Organic Chemistry | Han J.,CAS Shanghai Institute of Organic Chemistry | Wang L.,East China University of Science and Technology
Organic Letters | Year: 2015

A new family of tartaric acid derived chiral iminophosphoranes has been developed as highly effective organocatalysts in the asymmetric chlorinations of 3-substituted oxindoles with a high level of enantioselectivity. Importantly, these catalysts are air- and moisture-stable. Recovery of the catalyst after simple chromatographic separation for reuse in the model reaction was achieved; the catalyst can be recycled six times without loss of any enantioselectivity. Several advantages of this catalytic process are high conversion after a very short reaction time at ambient temperature, low catalytic loading, and scale-up to multigram quantities with an excellent enantiomeric excess value of >99%, which meets the enantiomeric purity required for pharmaceutical purposes. © 2015 American Chemical Society.


Jiang H.,Nanyang Technological University | Jiang H.,East China University of Science and Technology | Zhao T.,Nanyang Technological University | Ma J.,Nanyang Technological University | And 2 more authors.
Chemical Communications | Year: 2011

Ultrafine MnO2 nanowires with sub-10 nm diameters have been synthesized by a simple process of hydrothermal treatment with subsequent calcinations to form networks that exhibit an enhanced specific capacitance (279 F g-1 at 1 A g-1), high rate capability (54.5% retention at 20 A g-1) and good cycling stability (1.7% loss after 1000 cycles). © 2011 The Royal Society of Chemistry.


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.


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.


Wang F.,East China University of Science and Technology | Liu L.-J.,East China University of Science and Technology | Wang W.,East China University of Science and Technology | Li S.,East China University of Science and Technology | And 2 more authors.
Coordination Chemistry Reviews | Year: 2012

The strong σ-donor but poor π-acceptor abilities of N-heterocyclic carbenes (NHCs) result in chemical stability and coordination versatility, thus allowing them to coordinate with many metals ranging from alkaline-earth metals to rare-earth metals. Moreover, the easy introduction of chiral elements into NHCs and the facile preparation of their precursors have made chiral NHCs promising chiral ligands in metal-based asymmetric catalysis. Therefore, strategies for the design of efficient NHC-metal catalysts and novel asymmetric synthetic methodologies have dramatically increased over the past 10 years. Herein, the growing field of chiral NHC-metal-based asymmetric catalysis is comprehensively described. © 2011 Elsevier B.V..


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.


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.


Jiang H.,East China University of Science and Technology | Ma J.,Nanyang Technological University | Li C.,East China University of Science and Technology
Chemical Communications | Year: 2012

We demonstrate a simple and scalable strategy for synthesizing hierarchical porous NiCo 2O 4 nanowires which exhibit a high specific capacitance of 743 F g -1 at 1 A g -1 with excellent rate performance (78.6% capacity retention at 40 A g -1) and cycling stability (only 6.2% loss after 3000 cycles). © 2012 The Royal Society of Chemistry.


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.


Deng Y.,CAS Shanghai Institute of Organic Chemistry | Li Y.,CAS Shanghai Institute of Organic Chemistry | Dai J.,East China University of Science and Technology | Lang M.,East China University of Science and Technology | Huang X.,CAS Shanghai Institute of Organic Chemistry
Journal of Polymer Science, Part A: Polymer Chemistry | Year: 2011

Graphene nanosheets offer intriguing electronic, thermal and mechanical properties and are expected to find a variety of applications in high-performance nanocomposite materials. The great challenge of exfoliating and dispersing pristine graphite or graphene sheets in various solvents or matrices can be achieved by facilely and properly chemical functionalization of the carbon nanosheets. Here we reported an efficient way to functionalize graphene sheets with presynthesized polymer via a combination of atom transfer nitroxide radical coupling chemistry with the grafting-onto strategy, which enable us to functionalize graphene sheets with well-defined polymer synthesized via living radical polymerization. A radical scavenger species, 2,2,6,6- tetramethylpiperidine-1-oxyl (TEMPO), was firstly anchored onto -COOH groups on graphene oxide (GO) to afford TEMPO-functionalized graphene sheets (GS-TEMPO), meanwhile, the GO sheets were thermally reduced. Next, GS-TEMPO reacted with Br-terminated well-defined poly(N-isopropylacrylamide) (PNIPAM) homopolymer, which was presynthesized by SET-LRP, in the presence of CuBr/N,N,N′, N′,Na″-pentamethyldiethylenetriamine to form PNIPAM-graphene sheets (GS-PNIPAM) nanocomposite in which the polymers were covalently linked onto the graphene via the alkoxyamine conjunction points. The PNIPAM-modified graphene sheets are easily dispersible in organic solvents and water, and a temperature-induced phase transition was founded in the water suspension of GS-PNIPAM. © 2011 Wiley Periodicals, Inc.


Jiang H.,East China University of Science and Technology | Sun T.,Nanyang Technological University | Li C.,East China University of Science and Technology | Ma J.,Nanyang Technological University
Journal of Materials Chemistry | Year: 2012

Three kinds of hierarchical porous nanostructures assembled from ultrathin MnO 2 nanoflakes with different sizes and crystallinities, have been synthesized by a very simple and scalable strategy. When applied as electrode materials for supercapacitors, all of them exhibited enhanced electrochemical performances due to the high utilization of active materials. More significantly, based on these ultrathin nanostructures, we have discussed the relationships between their specific areas, pore sizes and crystallinities and their electrochemical performances. Among them, the product synthesized in an ice bath with an especially high specific area (269 m 2 g -1), uniform pore size distribution (∼5.1 nm) and poor crystallinity, exhibited the highest specific capacitance (328 F g -1) with a high rate and cycling stability. It is thought that the hierarchical ultrathin porous nanostructures can serve as promising electrode materials for supercapacitors. © 2012 The Royal Society of Chemistry.


Pei C.-K.,East China University of Science and Technology | Shi M.,East China University of Science and Technology | Shi M.,CAS Shanghai Institute of Organic Chemistry
Tetrahedron Asymmetry | Year: 2011

Cinchona alkaloid derived catalyst cat. 5 prepared from β-isocupreidine (b-ICD) was found to be a fairly effective organocatalyst for the nucleophilic promoted asymmetric [4+2] cycloaddition reaction of salicyl N-tosylimines and allenic esters to give the corresponding adducts in up to 80% yield, 87% ee. © 2011 Elsevier Ltd. All rights reserved.


Jiang H.,East China University of Science and Technology | Ma J.,Nanyang Technological University | Li C.,East China University of Science and Technology
Journal of Materials Chemistry | Year: 2012

We demonstrated the facile loading of ultrafine and loosened K-birnessite MnO 2 floccules on the surface of polyaniline (PANI) nanofibers by simply soaking the polyaniline nanofibers in a KMnO 4 aqueous solution for electrochemical energy storage applications. The as-prepared PANI-MnO 2 coaxial nanofibers with optimal composition, when applied as an electrode, exhibited a high specific capacitance (383 F g -1 at 0.5 A g -1) with good rate and cycling stability in 1 M Na 2SO 4 aqueous solution. Such intriguing electrochemical performance is mainly attributed to the synergistic effects of the combined pseudo-capacitive contributions from the core and shell. The present findings promoted the development of advanced electrode materials, exhibiting huge potential for supercapacitors. © The Royal Society of Chemistry 2012.


Zhang X.-N.,East China University of Science and Technology | Shi M.,East China University of Science and Technology | Shi M.,CAS Shanghai Institute of Organic Chemistry
European Journal of Organic Chemistry | Year: 2012

An asymmetric variant of the intramolecular Rauhut-Currier (RC) reaction can be achieved using a highly nucleophilic multifunctional chiral phosphane; the corresponding cyclopentene and cyclohexene derivatives are produced in moderate to good yields and with good to excellent enantioselectivities. © 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.


Jiang H.,East China University of Science and Technology | Jiang H.,Nanyang Technological University | Yang L.,Nanyang Technological University | Li C.,East China University of Science and Technology | And 3 more authors.
Energy and Environmental Science | Year: 2011

In this paper, using manganese oxide as an example, we report the successful design and synthesis of a novel one-dimensional highly graphitic carbon-tipped manganese oxide/mesoporous carbon/ manganese oxide hybrid nanowire. The unique structure significantly improves the conductivity of metal oxide materials, which is a key limitation in pseudocapacitors. The hybrid nanowire with optimal carbon content, when applied as an electrode, exhibits superior capacitive properties in 1 M Na2SO4 aqueous solution, such as high specific capacitance (266 F g-1 at 1 A g-1), excellent rate capability (56.4% capacity retention at 60 A g-1) and outstanding cycling stability (without degradation after 1200 cycles). The energy densities achieved can be as high as 20.8Wh kg-1, at a power density of 30 kW kg-1. The results demonstrated that the manganese oxide in our hybrid nanomaterial was efficiently utilized with the assistance of the highly conductive graphitic carbon-tipped mesoporous carbon shell. It is reckoned that the present low-cost novel hybrid nanowire can serve as a promising electrode material for supercapacitors and other electrochemical devices. © The Royal Society of Chemistry 2011.


Lu J.,East China University of Science and Technology | Ye J.,East China University of Science and Technology | Duan W.-L.,CAS Shanghai Institute of Organic Chemistry
Chemical Communications | Year: 2014

Palladium-catalyzed asymmetric 1,6-addition of diarylphosphines to electron-deficient dienes was developed through rational selection of electron-withdrawing groups on the dienes. Various chiral allylic phosphine derivatives were synthesized in good yields with high enantioselectivity (up to 96% ee). © 2014 The Royal Society of Chemistry.


Pei C.-K.,East China University of Science and Technology | Jiang Y.,East China University of Science and Technology | Shi M.,East China University of Science and Technology | Shi M.,CAS Shanghai Institute of Organic Chemistry
Organic and Biomolecular Chemistry | Year: 2012

β-Isocupreidine (β-ICD) catalyzed asymmetric [4 + 2] cycloaddition of β,γ-unsaturated α-ketoesters with allenic esters afforded ester-substituted functionalized dihydropyran derivatives in high yields along with high enantioselectivities under mild conditions. © 2012 The Royal Society of Chemistry.


Hu F.,East China University of Science and Technology | 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
Tetrahedron | Year: 2012

The [3+2] annulation reactions of 2-arylideneindane-1,3-diones with Morita-Baylis-Hillman (MBH) carbonates proceeded smoothly in the presence of multifunctional thiourea-phosphines to produce the corresponding quaternary carbon centered spirocyclic cyclopentenes in moderate yields, with high diastereoselectivities and enantioselectivities under mild conditions. The plausible reaction has been also discussed on the basis of previous literature. © 2012 Elsevier Ltd. All rights reserved.


Chen X.,East China University of Science and Technology | Hou Y.,East China University of Science and Technology | Zhang B.,East China University of Science and Technology | Yang X.H.,East China University of Science and Technology | And 2 more authors.
Chemical Communications | Year: 2013

SnS nanosheets (NSs), SnS nanowires (NWs) and SnS2 nanosheets were synthesized and investigated as counter electrode (CE) catalysts in a I3 -/I- based dye-sensitized solar cell (DSC) system for the first time. It is found that the SnS NS based DSCs show comparable power-conversion efficiency (Eff = 6.56%) to Pt (7.56%), while the Eff of SnS NW and SnS2 NS based DSCs are 5.00% and 5.14% respectively, indicating the excellent catalytic activity of SnS x for the reduction of triiodide to iodide. © 2013 The Royal Society of Chemistry.


Fan F.,East China University of Science and Technology | Xie W.,CAS Shanghai Institute of Organic Chemistry | Ma D.,East China University of Science and Technology | Ma D.,CAS Shanghai Institute of Organic Chemistry
Organic Letters | Year: 2012

An efficient protocol for assembling a polycyclic spiroindoline scaffold is developed, which involves an intramolecular oxidative coupling of dianions derived from indole-embodied β-ketoamides using iodine as the oxidant, and subsequent attack of oxygen anion to the resultant imine moiety. A number of tetracyclic spiroindolines are prepared with moderate to good yields. © 2012 American Chemical Society.


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.


Pei C.-K.,East China University of Science and Technology | Jiang Y.,East China University of Science and Technology | Wei Y.,CAS Shanghai Institute of Organic Chemistry | Shi M.,East China University of Science and Technology
Angewandte Chemie - International Edition | Year: 2012

Tell me which you want: Catalytic asymmetric [4+2] cycloadditions of β,γ-unsaturated α-ketophosphonates with allenic esters catalyzed by organocatalysts derived from different cinchona alkaloids have been developed, affording phosphonate-substituted functionalized pyran and dihydropyran derivatives in excellent yields with high enantioselectivities under mild conditions. The choice of product is controlled by the hydrogen bonding characteristics of the chosen catalyst. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhu Z.-B.,CAS Shanghai Institute of Organic Chemistry | Wei Y.,East China University of Science and Technology | Shi M.,CAS Shanghai Institute of Organic Chemistry | Shi M.,East China University of Science and Technology
Chemical Society Reviews | Year: 2011

This critical review discusses recent developments in the field of cyclopropene chemistry. Although several excellent reviews that mainly focused on the thermolysis and pyrolysis as well as metal-mediated reactions of cyclopropenes have been published, significant new developments have also been achieved in recent years. This brand new review provides an overview of the progress from 2007 to 2011 on the syntheses and transformations of cyclopropenes as well as their related mechanistic studies (238 references). © 2011 The Royal Society of Chemistry.


Mei L.-Y.,East China University of Science and Technology | Wei Y.,CAS Shanghai Institute of Organic Chemistry | Xu Q.,East China University of Science and Technology | Shi M.,East China University of Science and Technology | Shi M.,CAS Shanghai Institute of Organic Chemistry
Organometallics | Year: 2013

A novel asymmetric formal [3+2] cycloaddition of vinyl cyclopropanes and isatins in the presence of Pd2(dba)3 and the chiral imidazoline-phosphine ligand (aS,R,R)-L3 has been developed, affording the corresponding highly functionalized oxindole-fused spirotetrahydrofuran frameworks in good yields along with good diastereo- and high enantioselectivities under mild conditions. © 2013 American Chemical Society.


Huang L.,East China University of Science and Technology | Shi M.,East China University of Science and Technology | Shi M.,CAS Shanghai Institute of Organic Chemistry
Chemical Communications | Year: 2012

The phase-transfer catalyst promoted intramolecular transformation of pyrrole-2-carbaldehyde substituted Morita-Baylis-Hillman adducts has been disclosed, providing an efficient way to construct pyrrolo[1,2-a]azepin-7(6H)- one skeletons in moderate to good yields (up to 92%) under mild conditions. © 2012 The Royal Society of Chemistry.


Jiang H.,East China University of Science and Technology | Li C.,East China University of Science and Technology | Sun T.,Nanyang Technological University | Ma J.,Nanyang Technological University
Chemical Communications | Year: 2012

Ni(OH) 2/MnO 2 core-shell nanowires with a nanoflake surface have been designed and synthesized, and can be applied not only in neutral electrolytes (355 F g -1, 70.4 wt% MnO 2) but are also appropriate for alkaline electrolytes (487.4 F g -1, 35.5 wt% MnO 2), with high cycling stability due to the synergistic effect between the core and shell. This journal is © The Royal Society of Chemistry 2012.


Fan F.,East China University of Science and Technology | Xie W.,CAS Shanghai Institute of Organic Chemistry | Ma D.,East China University of Science and Technology | Ma D.,CAS Shanghai Institute of Organic Chemistry
Chemical Communications | Year: 2012

A concise synthesis of polycyclic pyrroloindolines from simple malonic diamides via an intramolecular oxidative coupling/condensative cyclization cascade process is reported. The reaction provides an efficient method to construct polycyclic pyrroloindolines in good to excellent yields, which should be useful in the synthesis of natural products and pharmaceutical molecules. © 2012 The Royal Society of Chemistry.