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Hangzhou, China

Zhejiang University of Technology is located in the city of Hangzhou, Zhejiang Province. It is considered one of the top industrial universities in mainland China and the second largest university in Zhejiang Province after the most comprehensive university - Zhejiang University.Engineering, especially chemical and biological engineering, is its strongest element. During the 1980s it made an effort to become a comprehensive technological university instead of a technological college. It keeps a close and broad relationship to industry.It is a typical technical university of the new generation in China. It followed the trend during the 1980s and 1990s of Chinese technical institutes changing from the soviet specialized style into a much more comprehensive style. Wikipedia.

Hu B.,East China University of Science and Technology | Meng M.,East China University of Science and Technology | Wang Z.,East China University of Science and Technology | Du W.,East China University of Science and Technology | And 4 more authors.
Journal of the American Chemical Society | Year: 2010

Novel planar chiral ferrocene nucleophilic catalysts (Fc-PIP) containing both central and planar chiral elements were designed and synthesized for catalytic enantioselective acyl transfer of secondary alcohols. A remarkably efficient catalyst with high selectivity factors (up to S = 1892) was identified. Comparing the combination of central and planar chirality revealed a strong requirement for the "matched" chiral elements, indicating that the stereogenic center of the imidazole rings should present itself on the same face as the ferrocenyl fragment; otherwise, the catalyst is completely inactive. An exclusively stacked transition state that accounts for the high selectivity of the kinetic resolution of secondary alcohols is proposed. Notably, this newly designed catalyst family is suitable for the catalytic kinetic resolution of bulky arylalkyl carbinols, producing esters with extremely high ee (>99%). © 2010 American Chemical Society.

Wang G.,Zhejiang University of Technology
Journal of Geotechnical and Geoenvironmental Engineering | Year: 2010

This paper presents an analytical solution for the consolidation of soft soil foundations reinforced by stone columns under time-dependent loadings. The differential equations of the foundations reinforced by stone columns are obtained including smear and well resistance under arbitrary applied loadings. The closed-form solutions of pore pressure and the overall average degree of consolidations are obtained for some common types of loadings, such as step loading, ramp loading, and cyclic trapezoidal loading. By solving the equations using a semianalytical method, the comparisons agree very well with the existing analytical solutions, which verify the correctness and accuracy of the proposed methods. Using the solutions obtained, some selected charts are presented and the relevant consolidation behavior is investigated and discussed. © 2009 ASCE.

Xu Z.-F.,University of Pittsburgh | Li X.,University of Maryland University College | Zoller P.,Austrian Academy of Sciences | Zoller P.,University of Innsbruck | And 2 more authors.
Physical Review Letters | Year: 2015

We study a mixture of spin-1 bosonic and spin-1/2 fermionic cold atoms, e.g., Rb87 and Li6, confined in a triangular optical lattice. With fermions at 3/4 filling, Fermi surface nesting leads to spontaneous formation of various spin textures of bosons in the ground state, such as collinear, coplanar, and even noncoplanar spin orders. The phase diagram is mapped out with varying boson tunneling and Bose-Fermi interactions. Most significantly, in one noncoplanar state the mixture is found to exhibit a spontaneous quantum Hall effect in fermions and crystalline superfluidity in bosons, both driven by interaction. © 2015 American Physical Society.

Yang J.J.,Zhejiang University of Technology
Zhongguo ying yong sheng li xue za zhi = Zhongguo yingyong shenglixue zazhi = Chinese journal of applied physiology | Year: 2013

To investigate the effect of ursolic acid (UA) on the alloxan-induced myocardial fibrosis in mice and discuss the possible mechanism. Diabetes was produced by a single injection of alloxan (70 mg/kg, i.v.) in mice. The mice were randomly divided into four groups: normal control group, model group, ursolic acid group (UA, 35 mg/kg, p.o.) and benazepril group (5 mg/kg, p. o.), and continuous administrated for 8 weeks. The blood glucose was measured 24 hours after the last administration. Detected the specific biochemical of myocardial tissue: superoxide dismutase (SOD), malondialdehyde (MDA) and hydroxyproline(HYP). Using masson staining to observe the morphology of the myocardial tissue. Immunohistochemistry was employed to determine the protein levels of TGF-beta1. Compared to normal group, the blood glucose, heart index, myocardial tissue MDA, HYP level were increased, and SOD activities were decreased in the diabetic mice, Masson stain showed that myocardial cells disarranged, myocardial collagen fibrosis hyperplasia. Meanwhile, the protein expression of TGF-beta1 was increased in model group. The UA group improved all the above significantly. UA improves the myocardial collagen fibrosis in diabetic mice induced by alloxan, its mechanism may be related to inhibiting the expression of TGF-beta1 and antioxidation.

Chen L.,Zhejiang University of Technology
Journal of Surfactants and Detergents | Year: 2012

Nonylphenol ethoxylates (NPEOs) are widely used as surfactants for emulsion polymerization and for post adding stabilization for latex applications in formulations with high filler content. However, NPEOs are bioaccumulative and persistent in the environment while nonylphenol, the breakdown product of NPEs, is an endrocrine disruptor. Therefore, it has been recommended to ban technical processes using NPEOs as surfactants. The acrylic polymer latex was prepared via semi-continuous seeded emulsion polymerization of butyl acrylate and methyl methacrylate in water phase initiated with potassium persulfate when nonylphenol ethoxylates are replaced with alkyl polyglycoside (APG) surfactants. The structure of the resultant acrylic polymer latex is confirmed with Fourier transform infrared spectroscopy spectrum. Differential scanning calorimetry confirms that the resultant latex is a kind of random copolymer and the consistency among the chain segment is fairly good. Influences of amount of APG on the properties of the resultant latex and its film were investigated. Results show that the particle size of the latex is decreased with the increase of the amount of APG. And the ionic stability of latex is also improved with the increase of the amount of APG. However, the water-resistance of the film of the latex is decreased with the increase of the amount of APG. © 2012 AOCS.

Ooi S.W.,University of Cambridge | Shirzadi A.A.,Open University Milton Keynes | Yang J.,Zhejiang University of Technology
Materials Today: Proceedings | Year: 2015

The crystallographic orientation relationship between the reverse austenite and corresponding martensite in a new residual-stress-reducing weld metal was predicted, using the general theory of martensitic transformation, and verified experimentally. The theoretical and experimental results of this work also provided an evidence of the likelihood of austenite memory phenomenon. © 2015 The Authors.

Lu Z.,University of California at Riverside | Lin K.,Zhejiang University of Technology | Gan J.,University of California at Riverside
Environmental Pollution | Year: 2011

Bisphenol F (BPF), an environmental estrogen, is used as a monomer in plastic industry and its environmental fate and decontamination are emerging concern. This study focused on the kinetics, influencing factors and pathways of its oxidation by MnO 2. At pH 5.5, about 90% of BPF was oxidized in 20 min in a solution containing 100 μM MnO 2 and 4.4 μM BPF. The reaction was pH-dependent, following an order of pH 4.5 > pH 5.5 > pH 8.6 > pH 7.5 > pH 6.5 > pH 9.6. Humic acids inhibited the reaction at low (≤pH 5.5) and high pH (≥pH 8.6) at high concentrations. In addition, metal ions and anions also suppressed the reaction, following the order Mn 2+ > Ca 2+ > Mg 2+ > Na + and HPO 4 2- > Cl - > NO 3 - ≈ SO 4 2-, respectively. A total of 5 products were identified, from which a tentative pathway was proposed. © 2010 Published by Elsevier Ltd.

Chen H.L.,Zhejiang University of Technology
Yi chuan = Hereditas / Zhongguo yi chuan xue hui bian ji | Year: 2013

Mammalian neurogenesis is a highly complicated process with programmed morphology and function evolution. Polarity, a basic characteristic in neurogenesis, is controlled by regulating proteins such as the partition defective (Par) proteins. Par polarity complex is the most investigated Par protein among these polarity proteins. There are developmental dynamic changes during neurogenesis for the protein distribution and content, which are related to the junction establishment, polarity formation, synaptogenesis, and neuronal migration. Moreover, Par complex is considered to affect the developmental fate of neural precursors. This study summarizes the advances of the protein cellular location, function, and mechanism in embryal neocortex and cultured neuron.

Song X.C.,Fujian Normal University | Wang X.,Fujian Normal University | Zheng Y.F.,Zhejiang University of Technology | Ma R.,Fujian Normal University | Yin H.Y.,Hangzhou Dianzi University
Journal of Nanoparticle Research | Year: 2011

In this article, the Ag nanoparticles were synthesized on indium tin oxide conducting glass (ITO) substrate using the electrochemical deposition method. The morphology analysis of the deposits using scanning electron microscope (SEM) reveals that the sizes and densities of the Ag nanoparticles were tuned by varying the time of electrodeposition. The structure of the deposits was characterized by X-ray diffraction (XRD). The prepared Ag nanoparticles electrode was then applied to detect hydrogen peroxide (H2O 2) in 0.01 M pH 7.0 phosphate buffer medium. The present electrochemical sensing platform exhibited good electrocatalytic activity towards the reduction of H2O2. The detection sensitivity of the sensor was 0.237 mA mM-1. This method is very simple, inexpensive, and undemanding, thus it should be extensively applied in many fields for the detection of H2O2. © 2011 Springer Science+Business Media B.V.

Yang S.-L.,Zhejiang University of Technology | Duan Z.-Q.,Academy of State Administration of Grain
Catalysis Communications | Year: 2016

Deep eutectic solvents (DESs) have recently attracted a significant interest in numerous fields including biocatalysis because they are inexpensive, environmentally friendly, non-toxic, biodegradable, and enzyme compatible. Herein, these solvents were successfully used as the reaction media for enzyme-mediated transphosphatidylation of phosphatidylcholine with l-serine for the synthesis of phosphatidylserine for the first time. Enzymatic phosphatidylserine synthesis in various DESs was comprehensively investigated, employing phospholipase D. Our results indicated that > 90% yield of phosphatidylserine could be achieved using choline chloride/ethylene glycol as DES. Furthermore, 81% original activity of the enzyme was maintained after being used for 10 batches. This study indicates that DESs act as potential candidates for the eco-friendly solvents in biocatalysis applications. © 2016 Elsevier B.V. All rights reserved.

Li Y.-L.,Southwest Jiaotong University | Li Y.-L.,Northeastern University China | Tang J.-F.,Northeastern University China | Chin K.-S.,City University of Hong Kong | And 2 more authors.
Information Sciences | Year: 2012

Quality function deployment (QFD) is a planning and problem-solving methodology used to translate customer requirements (CRs) into engineering characteristics (ECs) in the course of new product development (NPD). Estimating the correlation measures among ECs is a crucial step in the product planning house of quality (PPHOQ) construction process because these measures seriously affect the planning of development efforts. This study presents a rough set-based approach used to estimate the correlation measures by revealing the knowledge of a QFD team. The approach involves introducing the category factor of a correlation to express the influences of the correlation categories on the corresponding correlation measures. A case study of a two-cylinder washing machine is used to illustrate the proposed approach. The result shows that the novel approach is effective in revealing the related knowledge of the QFD team and facilitating NPD decision making. © 2011 Elsevier Inc. All rights reserved.

Sun M.X.,Zhejiang University of Technology | Wang D.W.,Nanyang Technological University | Chen P.N.,China Institute of Metrology
Science in China, Series F: Information Sciences | Year: 2010

Iterative learning control requires initial repositioning, while the time functions to be learned should be of periodicity in repetitive control. However, there are cases in practice where the time-varying unknowns are not periodic but repetitive, and repetitive learning control is applicable with avoidance of initial repositioning. In this paper, repetitive learning control designs are presented for a broader class of nonlinear systems over finite intervals. The Freeman formula is modified and used for stabilization of the nominal nonlinear time-varying system undertaken. The global stability of the learning system and asymptotic convergence of the tracking error are established through analysis of both partially and fully saturated learning algorithms, respectively. The repetitive learning control method is theoretically shown to be effective in dealing with time-varying parametric uncertainties. © Science China Press and Springer-Verlag Berlin Heidelberg 2010.

Zheng D.,Zhejiang University of Technology
Textile Research Journal | Year: 2014

A novel method combining the characteristics of corner information and second-order statistics of fabric images is proposed for analyzing the repeat size and identifying the weave type of fabrics. The analysis method is formulated in a research framework of near regular texture analysis. Firstly, the original fabric image is split into two components: the geometric component and the textural component, in which low-level cues of corners are detected by the Harris detector. Secondly, clustering techniques are used to cluster interest points by image patch appearance. Thirdly, a Markov Random Field (MRF) model is adopted for inferring the location of texture elements, and their shape is then used for classifying the weave patterns. The experimental results show that the main disadvantages and difficulties of using structural and frequency methods in texture classifications have been overcome by the proposed method. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Wang K.,Academy of Armored force Engineering | Zheng Y.J.,Zhejiang University of Technology
Applied Intelligence | Year: 2012

Armored vehicle design is a complex constrained optimization problem which often involves a number of fuzzy and stochastic parameters. In this paper, a fuzzy optimization problem model of armored vehicle scheme design is presented, and a new particle swarm optimization (PSO) algorithm is proposed for effectively solving the problem. The problem model uses fuzzy variables to evaluate the objective function and constraints of the problem. The algorithm employs multiple ranking criteria to define three global bests of the swarm, makes different quality particles learning from different global bests, and thus search effectively through the solution space by means of multi-criteria optimization. Experiment results show that our approach can achieve good solution quality with low computational costs. © 2012 Springer Science+Business Media, LLC.

Yuan W.-B.,Zhejiang University of Technology
Journal of Constructional Steel Research | Year: 2013

In this paper, the geometric nonlinear bending response of angle-section beams of finite length is investigated by using energy methods. The basic assumptions used in the present study are that the total strain energy of an angle-section beam subjected to pure bending can be simplified into a two-stage process. One is the bending response of the two legs behaving as the plate; the other is the overall bending response as a beam with flattened section. The nonlinear bending response is derived by applying the minimum potential energy principle and the corresponding static and dynamic critical moments associated with the section flattening-induced buckling are determined. To validate the analytical solution developed, geometric nonlinear finite element analyses are also conducted. Good agreement between the present solution and the FEA results is demonstrated. © 2013 Elsevier Ltd.

Xiao J.,Nankai University | Cheng Z.,Zhejiang University of Technology
Journal of Computational and Theoretical Nanoscience | Year: 2013

In DNA computing and DNA nanotechnology, the DNA encoding is one of the most practical and important research topics. DNA encoding need meet simultaneously several physical, chemical and logical constraints, which has been proved to be an NP-hard problem. In the paper, a multi-swarm particle swarm optimization is proposed to deal with DNA encodings problem. The method proposed used the local PSO with the time-varying acceleration coefficients (TVAC) as the search engine for each sub-swarms, and incorporated the differential evolution to improve the swarm search space. The results of simulation experiments show that the proposed algorithm is valid and outperforms other evolutionary algorithms. Copyright © 2013 American Scientific Publishers All rights reserved.

Zhou C.H.,Zhejiang University of Technology | Keeling J.,Geological Survey of Western Australia
Applied Clay Science | Year: 2013

This brief overview comments on recent trends in scientific research and development of clay minerals and was stimulated by the compilation of papers for this special issue to pay tribute to the 34th International Geological Congress held in 2012. The essentially geological context of the conference was a reminder that increased understanding of the genesis and evolution of clays and clay minerals provides insights that have applications in mining, environmental management, paleoclimate, Earth and extraterrestrial sciences. The requirement for multidisciplinary knowledge, including geology, mineralogy, chemistry and materials science, and modern instrumentation and analysis of clay minerals, is essential to a full understanding of the genesis, role and potential new uses for these fine-grained industrial minerals. Latest studies are typically focused on processing and modifying of clay minerals as adsorbents, catalysts, and biomaterials. The emphasis for future work is on advanced clay-based nanomaterials for use in new approaches to sustainable energy, green environment, and human health. © 2013 Elsevier B.V.

Zou T.,CAS Shenyang Institute of Automation | Wei F.,Zhejiang University of Technology | Zhang X.-H.,ENN Group
Zidonghua Xuebao/Acta Automatica Sinica | Year: 2013

Aiming at reducing the on-line computational burden of model predictive control (MPC) for large-scale systems and maintaining the global optimization performance, a new two-layered MPC strategy is proposed. In the steady-state target calculation (SSTC) layer, the centralized optimization of the system is based on the global process model. The optimal results are sent to the dynamic control layer as the set points. In dynamic control layer, the large-scale system is divided into several subsystems which will be controlled with separate MPCs. To compensate the interference between the subsystems, feed-forward controllers are added between the subsystems, so that the overall dynamic control performance of the system will be improved. The advantages of the proposed strategy are that, the global optimal performance of the system is guaranteed, while the on-line computational complexity is reduced, and the real-time property of the two-layered MPC for large industrial system is enhanced. Simulation examples are given to verify the proposed method. Copyright © 2013 Acta Automatica Sinica. All rights reserved.

Guo A.-M.,Nanjing University | Guo A.-M.,Zhejiang University of Technology | Xiong S.-J.,Nanjing University
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

We investigate the electronic properties of a two-leg ladder model by taking into account the combined effects of long-range correlations along the longitudinal direction and short-range correlations in the transverse direction. The strength of both correlations is measured by the correlation exponent α and by the interchain hopping integral λ, respectively. Within the framework of the tight-binding Hamiltonian, we calculate the density of states, the localization length, and the participation ratio. Our results indicate that the short-range correlations will induce a crossover from localization to delocalization in the side energy bands of the two-leg ladder with finite system size by increasing λ, and the long-range correlations will lead to a localization-delocalization transition by increasing α, while the electronic states in the central region are still localized. The two side energy bands will present truly delocalized states for α 2.6 in the thermodynamic limit. Furthermore, the two-leg ladders of different types of short-range correlations will show quite different localization properties. The system with the pair correlations, where the on-site energies at the same longitudinal positions of two chains always have opposite values, exhibits a larger localization length in the side energy bands. © 2011 American Physical Society.

Hu B.,University of Nebraska - Lincoln | Hu B.,Zhejiang University of Technology | Miller W.H.,University of Nebraska - Lincoln | Neumann K.D.,University of Nebraska - Lincoln | And 2 more authors.
Chemistry - A European Journal | Year: 2015

Iodoarenes are important synthons for a wide range of organic transformations. Here we report a general strategy to prepare singly iodinated electron-rich aromatic compounds through the intermediacy of diaryliodonium salts. This process, which incorporates a phase separation that greatly simplifies product purification, is an attractive replacement for the Sandmeyer approach to iodoarenes that are otherwise difficult to access. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Within the accuracy of first-order Born approximation, the visibility of intensity correlated field is derived for two cases, i.e., the scalar and electromagnetic plane wave scattering from quasi-homogeneous (QH) media, respectively. Analytical results indicate that the visibility of intensity correlated field depends on the strength of scattering potential and the ratio D/R for the scalar case, where D is the radius of fiber-optic probe, and R is the distance between the scatterer and the fiber-optic probe. Comparably, for the electromagnetic case, the corresponding visibility relates with the strength of scattering potential, polarization of incident waves and the ratio D/R. Furthermore, numerical simulations are performed to investigate the influences of above parameters on the mean value of visibility. Numerical results further reveal that the strength of scattering potential of QH media may be determined by solutions of the inverse scattering problem provided that the visibility of intensity correlated field is obtained from experiments. The results may provide potential applications for the reconstruction and determination of unknown scatterer in optical coherence tomography and ghost imaging using the pseudo thermal light.

Weng C.,China Jiliang University | Fu Y.,China Jiliang University | Jiang H.,Zhejiang University of Technology | Zhuang S.,Zhejiang University | Li H.,China Jiliang University
International Journal of Biological Macromolecules | Year: 2015

The honeybee's social behavior is closely related to the critical response to pheromone, while pheromone binding proteins (PBPs) play an important role in binding and transferring those pheromones. Here we report one known PBP, antennal special protein 1(ASP1), which has high affinity with a queen mandibular pheromone component, methyl-p-hydroxybenzoate (HOB). In this study, multiple fluorescent spectra, UV absorption spectra, circular dichroism (CD) spectra and molecular docking analysis were combined to clarify the binding process. Basically, fluorescence intensity of ASP1 could be considerably quenched by HOB with an appropriate interaction distance (3.1. nm), indicating that a complex, which is more stable in lower temperature, was formed. The fact δ. H<. 0, δ. S<. 0, by thermodynamic analysis, indicated the van der Waals and hydrogen bond as main driving force. Moreover, synchronous fluorescence spectra and CD spectra analysis showed the change of partial hydrophilicity of ASP1 and the increase of α-helix after HOB addition. In conclusion, ASP1 can strongly and spontaneously interact with HOB. But the binding ability decreases with the rise of temperature, which may be necessary for sufficient social stability of hives. This study provides elucidation of the detailed binding mechanism and potential physicochemical basis of thermal stability to the social behavior of honeybee. © 2014 Elsevier B.V.

Zhang Q.,East China University of Science and Technology | Jiang Y.,Zhejiang University of Technology | Zhang Y.,East China University of Science and Technology | Ye Z.,East China University of Science and Technology | And 2 more authors.
Polymer Degradation and Stability | Year: 2013

Porous poly(ε-caprolactone) (PCL) scaffolds are widely used as in vivo implants in tissue engineering, and their long-term degradation behaviors are of great importance for their in vivo performances. However, the influence of porosity on long-term degradation of PCL scaffold in phosphate buffer solution (PBS) has been rarely reported so far. Herein, a 72-week degradation study of PCL scaffolds with various porosities was conducted to elucidate the changes of physico-chemical properties such as weight, molecular weight, morphology and compressive modulus. Within 72 weeks, PCL scaffolds experienced three stages: stable stage, mechanical loss stage and structural collapse stage. The higher porosity induced the severer loss of weight, molecular weight and compressive modulus. It was found that a minimal acid autocatalysis also happened in the scaffold samples with low porosities (less than 85%). Cellular response on the scaffolds with various porosities was further evaluated. The cell ingrowth improved on the scaffold with high porosity (e.g. S-10) in contrast to those with low porosity (e.g. S-6 and S-4). The combined results demonstrated that an optimal porosity of PCL scaffolds should be designed greater than 90% due to the appropriate degradation rate and good cell performance. © 2012 Elsevier Ltd. All rights reserved.

Xiong Y.,Zhejiang University of Technology | Yu Q.,University of Nevada, Reno | Jiang Y.,University of Nevada, Reno
Materials Science and Engineering A | Year: 2012

Multiaxial fatigue behavior of extruded AZ31B magnesium alloy was experimentally studied in ambient air under strain-controlled axial-torsion loading using tubular specimens. Four fully reversed loading paths were employed: tension-compression, pure torsion, proportional axial-torsion, and 90° out-of-phase nonproportional axial-torsion. Tension-compression asymmetry in cyclic plastic deformation was observed for tension-compression and combined axial-torsion loading. For the same equivalent strain amplitude, the 90° out-of-phase nonproportional loading path resulted in the shortest fatigue life and the proportional loading path produced the longest fatigue life. Two critical plane multiaxial fatigue models, namely, the modified Smith-Watson-Topper (SWT) model and the Jiang multiaxial fatigue criterion, were evaluated based on the experimentally obtained fatigue results. Both models were found to be able to correlate the fatigue experiments reasonably well. © 2012 Elsevier B.V.

Nassi J.J.,Salk Institute for Biological Studies | Avery M.C.,Salk Institute for Biological Studies | Cetin A.H.,Salk Institute for Biological Studies | Cetin A.H.,Allen Institute for Brain Science | And 3 more authors.
Neuron | Year: 2015

Normalization has been proposed as a canonical computation that accounts for a variety of nonlinear neuronal response properties associated with sensory processing and higher cognitive functions. A key premise of normalization is that the excitability of a neuron is inversely proportional to the overall activity level of the network. We tested this by optogenetically activating excitatory neurons in alert macaque primary visual cortex and measuring changes in neuronal activity as a function of stimulation intensity, with or without variable-contrast visual stimulation. Optogenetic depolarization of excitatory neurons either facilitated or suppressed baseline activity, consistent with indirect recruitment of inhibitory networks. As predicted by the normalization model, neurons exhibited sub-additive responses to optogenetic and visual stimulation, which depended lawfully on stimulation intensity and luminance contrast. We conclude that the normalization computation persists even under the artificial conditions of optogenetic stimulation, underscoring the canonical nature of this form of neural computation. The Normalization Model can account for a wide variety of neural computations, ranging from contrast gain control to attentional selection. Here, Nassi et al. find strong support for the model by combining optogenetic and visual stimulation in primate visual cortex. © 2015 Elsevier Inc.

Chen L.J.,Zhejiang University of Technology | Wu F.Q.,Intertek
Surface Engineering | Year: 2012

The novel fluorinated polyacrylate latex was successfully prepared by emulsion polymerisation of perfluorononylene allyl ether (PFAE) with butyl acrylate (BA) and methyl methacrylate (MMA) initiated by potassium persulphate (KPS) in the water with different surfactants. PFAE was synthesised from the intermediate perfluoro nonene and 3-allyl alcohol as staring reactants. Films of the novel fluorinated polyacrylate latex were prepared by coating the latex directly on the clean glass sheet and allowed to dry at 80°C in a bake oven. The structure of the novel fluorinated polyacrylate latex was investigated by Fourier transform infrared spectrometry. Surface difference of novel fluorinated polyacrylate latex prepared with different surfactants was studied. Results show that the latex prepared with sodium dodecyl benzene sulphonate surfactant has smaller particle size, contact angle and lower surface tension. The latex prepared with sodium 2-hydroxy-3-(methacryloyloxy) propane-1-sulphonate surfactant has larger particle size, higher surface tension and larger contact angle. © 2012 Institute of Materials, Minerals and Mining.

Yan X.,Zhejiang University | Zhou M.,Zhejiang University of Technology | Chen J.,Zhejiang University | Chi X.,Zhejiang University | And 6 more authors.
Chemical Communications | Year: 2011

Driven by the benzo-21-crown-7/secondary ammonium salt recognition motif, a linear supramolecular polymer was formed from self-organization of a low-molecular-weight self-complementary monomer in chloroform. From this supramolecular polymer, nanofibers were obtained successfully via electrospinning. © 2011 The Royal Society of Chemistry.

Wang W.,China National Rice Research Institute | Zhu T.,Zhejiang University of Technology | Lai F.,China National Rice Research Institute | Fu Q.,China National Rice Research Institute
European Food Research and Technology | Year: 2012

The transgenic rice line Kefeng-8 harboring insect-resistant genes Cry1Ac and CpTI showed ideal field performances characterized by high resistance to rice stem borer (Scirpophaga incertulas) and leaf roller (Cnaphalocrocis medinalis). This GM rice line is likely to be approved in China in the near future. In this study, we estimated the insert number of foreign genes, analyzed the flanking sequences of T-DNA in rice genome, and presented an event-specific detection method for this line. The results show that the foreign gene inserted one copy between position 11,774 and 11,805 of chromosome 11 (AC120536. 5) in Kefeng-8 genome. Based on these inserts and border sequences, the event-specific qualitative and quantitative PCR system was established for Kefeng-8. The qualitative detection limit was assessed to be 0. 1%, and the limit of quantitative method was assessed to be 100 initial template copies. Two mixed rice sample with known Kengfeng-8 contents were used to verify the quantitative method, from which the expected results were observed. This study provides a reliable method and information for detection, identification, and quantification of the presence of GM rice Kefeng-8. © 2012 Springer-Verlag.

Chen T.,University of Surrey | Liu Y.,Zhejiang University of Technology | Chen J.,Chung Yuan Christian University
Journal of Process Control | Year: 2013

In the application of on-line, dynamic process optimisation, adaptive estimation of the system states and parameters is usually needed to minimise the unavoidable model-process mismatch. This work presents an integrated approach to optimal model adaptation and dynamic optimisation, with specific focus on batch processes. An active approach is proposed whereby the input variables are designed so as to maximise the information content of the data for optimal model adaptation. Then, this active adaptation method is combined with the objective of process performance to form a multi-objective optimisation problem. This integrative approach is in contrast to the traditional adaptation method, where only the process performance is considered and adaptation is passively carried out by using the data as is. Two strategies for solving the multi-objective problem are investigated: weighted average and constrained optimisation, and the latter is recommended for the ease in determining the balance between these two objectives. The proposed methodology is demonstrated on a simulated semi-batch fermentation process. © 2013 Elsevier Ltd.

Sun M.,Zhejiang University of Technology
Automatica | Year: 2012

This paper presents a partial-period adaptive repetitive control method for a class of periodically time-varying nonlinear systems. To reduce the size of memory usage, the symmetric feature of periodic parameters is explored to form partial-period adaptation mechanisms. Both Half- and quarter-period adaptation strategies are proposed, and characterized analytically. The stability of the closed-loop system with each repetitive control is established, along with tracking error convergence to zero. In addition, the saturated-adaptation is suggested for providing bounded estimation. © 2012 Elsevier Ltd. All rights reserved.

Li M.,East China Normal University | Lim S.C.,28 Farrer Road and 05 01 | Chen S.,Zhejiang University of Technology
Mathematical Problems in Engineering | Year: 2011

Oscillator of single-degree-freedom is a typical model in system analysis. Oscillations resulted from differential equations with fractional order attract the interests of researchers since such a type of oscillations may appear dramatic behaviors in system responses. However, a solution to the impulse response of a class of fractional oscillators studied in this paper remains unknown in the field. In this paper, we propose the solution in the closed form to the impulse response of the class of fractional oscillators. Based on it, we reveal the stability behavior of this class of fractional oscillators as follows. A fractional oscillator in this class may be strictly stable, nonstable, or marginally stable, depending on the ranges of its fractional order. © 2011 Ming Li et al.

Li M.,East China Normal University | Zhao W.,University of Macau | Chen S.,Zhejiang University of Technology
Mathematical Problems in Engineering | Year: 2011

Scaling phenomena of the Internet traffic gain peoples interests, ranging from computer scientists to statisticians. There are two types of scales. One is small-time scaling and the other large-time one. Tools to separately describe them are desired in computer communications, such as performance analysis of network systems. Conventional tools, such as the standard fractional Brownian motion (fBm), or its increment process, or the standard multifractional fBm (mBm) indexed by the local Hlder function H(t) may not be enough for this purpose. In this paper, we propose to describe the local scaling of traffic by using D(t) on a point-by-point basis and to measure the large-time scaling of traffic by using E [H(t) ] on an interval-by-interval basis, where E implies the expectation operator. Since E [H(t) ] is a constant within an observation interval while D(t) is random in general, they are uncorrelated with each other. Thus, our proposed method can be used to separately characterize the small-time scaling phenomenon and the large one of traffic, providing a new tool to investigate the scaling phenomena of traffic. © 2011 Ming Li et al.

Li M.,East China Normal University | Cattani C.,University of Salerno | Chen S.-Y.,Zhejiang University of Technology
Mathematical Problems in Engineering | Year: 2011

Sea level fluctuation gains increasing interests in several fields, such as geoscience and ocean dynamics. Recently, the long-range dependence (LRD) or long memory, which is measured by the Hurst parameter, denoted by H, of sea level was reported by Barbosa et al. (2006). However, reports regarding the local roughness of sea level, which is characterized by fractal dimension, denoted by D, of sea level, are rarely seen. Note that a common model describing a random function with LRD is fractional Gaussian noise (fGn), which is the increment process of fractional Brownian motion (fBm) (Beran (1994)). If using the model of fGn, D of a random function is greater than 1 and less than 2 because D is restricted by H with the restriction D=2-H. In this paper, we introduce the concept of one-dimensional random functions with LRD based on a specific class of processes called the Cauchy-class (CC) process, towards separately characterizing the local roughness and the long-range persistence of sea level. In order to achieve this goal, we present the power spectrum density (PSD) function of the CC process in the closed form. The case study for modeling real data of sea level collected by the National Data Buoy Center (NDBC) at six stations in the Florida and Eastern Gulf of Mexico demonstrates that the sea level may be one-dimensional but LRD. The case study also implies that the CC process might be a possible model of sea level. In addition to these, this paper also exhibits the yearly multiscale phenomenon of sea level. Copyright © 2011 Ming Li et al.

Zhang X.-J.,Zhejiang University of Technology
Wind and Structures, An International Journal | Year: 2011

The cable system is generally considered to be a structural solution to increase the spanning capacity of suspension bridges. In this work, based on the Runyang Bridge over the Yangtze River, three case suspension bridges with different 3D cable systems are designed, structural dynamic characteristics, the aerostatic and aerodynamic stability are investigated numerically by 3D nonlinear aerostatic and aerodynamic analysis, and the cable system favorable to improve the wind-induced instability of long-span suspension bridges is also proposed. The results show that as compared to the example bridge with parallel cable system, the suspension bridge with inward-inclined cable system has greater lateral bending and tensional frequencies, and also better aerodynamic stability; as for the suspension bridge with outward-inclined cable system, it has less lateral bending and tensional frequencies, and but better aerostatic stability; however the suspension bridge is more prone to aerodynamic instability, and therefore considering the whole wind-induced instability, the parallel and inward-inclined cable systems are both favorable for long-span suspension bridges.

Zhou Z.,University of Pittsburgh | Zhou Z.,George Mason University | Zhao E.,George Mason University | Liu W.V.,University of Pittsburgh | Liu W.V.,Zhejiang University of Technology
Physical Review Letters | Year: 2015

Mott insulators with both spin and orbital degeneracy are pertinent to a large number of transition metal oxides. The intertwined spin and orbital fluctuations can lead to rather exotic phases such as quantum spin-orbital liquids. Here, we consider two-component (spin 1/2) fermionic atoms with strong repulsive interactions on the p band of the optical square lattice. We derive the spin-orbital exchange for quarter filling of the p band when the density fluctuations are suppressed, and show that it frustrates the development of long-range spin order. Exact diagonalization indicates a spin-disordered ground state with ferro-orbital order. The system dynamically decouples into individual Heisenberg spin chains, each realizing a Luttinger liquid accessible at higher temperatures compared to atoms confined to the s band. © 2015 American Physical Society.

Fei Liu S.,Zhejiang University | Wu Y.J.,Zhejiang University | Li J.,Zhejiang University of Technology | Ming Chen X.,Zhejiang University
Applied Physics Letters | Year: 2014

Effects of oxygen vacancies on the dielectric, electrical, and ferroelectric properties of Ba4Nd2Fe2Nb 8O30 ceramics were investigated. A dielectric relaxation above Tc can be ascribed to the trap-controlled ac conduction around doubly ionized oxygen vacancies. The dc conductivity of the N 2-annealed and O2-annealed samples is attributed to the long-range motion of the Vo××, and that of the as-sintered sample is considered to be governed by the electronic and oxygen-vacancy ionic mixed conduction mechanism. Low concentration and random distributed oxygen vacancies are propitious to the domain switching, while high concentration and allied oxygen defects hinder the domain-wall movement. © 2014 AIP Publishing LLC.

Chen L.,Zhejiang University of Technology | Wu F.,Intertek
Micro and Nano Letters | Year: 2012

Colloidal processing has been proved to be an ideal technology for nanopowder dispersion and to be an effective way to disperse nanopowders such as TiO 2, ZnO, CaCO 3, Cu, TiN, and so on. Few reports that are focused on the dispersion of nano-scaled ATO powder in aqueous media. In this Letter, the nano-ATO colloid suspension was prepared with colloidal processing. Nano-ATO powders were treated in aqueous media with ultrasonic wave and γ-methacryloxypropyl trimethoxy silane (MTS) was added as the coupling agent. The plausible modified mechanism of the silane coupling agent involves the hydrolysis of MTS, condensation of hydrolysis product and formation of a covalent bond, which is confirmed by Fourier transform infrared. Factors that affect the stability of nano-ATO colloid suspension were investigated in detail. Results show that the well-dispersed nano-ATO colloid suspension can be obtained under the following optimum conditions: the ultrasonication time is 30min; pH of the colloid suspension is controlled at 7.0; the amount of MTS is 5.0; the reaction temperature is 60°C. The particle size of nano-ATO colloid suspension is 65.2nm and its distribution is unimodal distribution, which is further confirmed with transmission electron microscopy. © 2012 The Institution of Engineering and Technology.

Cheng S.,Zhejiang University of Technology | Liu Y.,Nokia Inc.
Journal on Multimodal User Interfaces | Year: 2012

In this paper, we proposed and evaluated an adaptive recommendation system based on users' eye-tracking data and an optimization algorithm called IGA. An eye tracker was utilized to acquire users' eye movement data and extract three measures, which were respectively number of fixation, fixation duration and the first fixation on target item. Based on the results on the three measures, we inferred users' preferences and adjusted the user interfaces based on users' preferences. We developed a prototype system, which could adaptively recommend digital cameras to users. Then we conducted a user study with the prototype system and found that participants could identify their preferred products with a comparatively less time period and higher satisfaction. © 2011 OpenInterface Association.

Wang Y.,Nanyang Technological University | Chen L.,Nanyang Technological University | Mei J.-P.,Zhejiang University of Technology
IEEE Transactions on Fuzzy Systems | Year: 2014

As an important technique of data analysis, clustering plays an important role in finding the underlying pattern structure embedded in unlabeled data. Clustering algorithms that need to store all the data into the memory for analysis become infeasible when the dataset is too large to be stored. To handle such large data, incremental clustering approaches are proposed. The key idea behind these approaches is to find representatives (centroids or medoids) to represent each cluster in each data chunk, which is a packet of the data, and final data analysis is carried out based on those identified representatives from all the chunks. In this paper, we propose a new incremental clustering approach called incremental multiple medoids-based fuzzy clustering (IMMFC) to handle complex patterns that are not compact and well separated. We would like to investigate whether IMMFC is a good alternative to capturing the underlying data structure more accurately. IMMFC not only facilitates the selection of multiple medoids for each cluster in a data chunk, but also has the mechanism to make use of relationships among those identified medoids as side information to help the final data clustering process. The detailed problem formulation, updating rules derivation, and the in-depth analysis of the proposed IMMFC are provided. Experimental studies on several large datasets that include real world malware datasets have been conducted. IMMFC outperforms existing incremental fuzzy clustering approaches in terms of clustering accuracy and robustness to the order of data. These results demonstrate the great potential of IMMFC for large-data analysis. © 2014 IEEE.

Mei J.-P.,Zhejiang University of Technology | Chen L.,Nanyang Technological University
Expert Systems with Applications | Year: 2014

As one of the most fundamental yet important methods of data clustering, center-based partitioning approach clusters the dataset into k subsets, each of which is represented by a centroid or medoid. In this paper, we propose a new medoid-based k-partitions approach called Clustering Around Weighted Prototypes (CAWP), which works with a similarity matrix. In CAWP, each cluster is characterized by multiple objects with different representative weights. With this new cluster representation scheme, CAWP aims to simultaneously produce clusters of improved quality and a set of ranked representative objects for each cluster. An efficient algorithm is derived to alternatingly update the clusters and the representative weights of objects with respect to each cluster. An annealing-like optimization procedure is incorporated to alleviate the local optimum problem for better clustering results and at the same time to make the algorithm less sensitive to parameter setting. Experimental results on benchmark document datasets show that, CAWP achieves favorable effectiveness and efficiency in clustering, and also provides useful information for cluster-specified analysis. © 2014 Elsevier Ltd. All rights reserved.

Cai M.,Hong Kong Polytechnic University | Cai M.,Zhejiang University of Technology | Wang S.,Hong Kong Polytechnic University | Liang H.-H.,Hong Kong Polytechnic University
Separation and Purification Technology | Year: 2012

Response surface methodology (RSM) with a central composite rotatable design (CCRD) was employed to optimize the process of ultrasound-assisted ultrafiltration (UF) for Radix astragalus mixtures. The effects and mutual interaction of several parameters, namely ultrasonic power, ultrasonic irradiation mode, trans-membrane pressure (TMP) and temperature, on fouling degree (Y 1) and process duration (Y 2) were investigated simultaneously. The analysis of variance (ANOVA) demonstrates that the second order polynomial regression models were appropriate and significant, with R 2 of 0.9820 and 0.9581 for Y 1 and Y 2, respectively. The study also shows that TMP is the most significant factor, followed by the temperature, ultrasonic power and irradiation mode. The desirability function approach was used to find the optimum conditions to minimize fouling degree and process duration simultaneously. The optimum conditions were found to be at ultrasonic power of 120 W, continuous ultrasonic irradiation mode, TMP of 0.60 bar and temperature of 20 °C. The predicted responses are 40.2% for fouling degree and 57 min for process duration, which are in good agreement with the results obtained from the confirmation experiments, valued about 38.5-43% and 53-58 min respectively. The results indicate that the regression models are adequate and RSM is an efficient optimization tool for multi-responses and multi-variables study. © 2012 Elsevier B.V. All rights reserved.

Bai X.-L.,Northwest University, China | Yue T.-L.,Northwest University, China | Yuan Y.-H.,Northwest University, China | Zhang H.-W.,Zhejiang University of Technology
Journal of Separation Science | Year: 2010

A simple and efficient microwave-assisted extraction of polyphenols from industrial apple pomace was developed and optimized by the maximization of the yield using response surface methodology. A Box-Behnken design was used to monitor the effect of microwave power, extraction time, ethanol concentration and ratio of solvent to raw material (g/mL) on the polyphenols yield. The results showed that the optimal conditions were as follows: microwave power 650.4 W, extraction time 53.7 s, ethanol concentration 62.1% and ratio of solvent to raw material 22.9:1. Validation tests indicated that the actual yield of polyphenols was 62.68±0.35 mg gallic acid equivalents per 100 g dry apple pomace with RSD=0.86% (n=5) under the optimal conditions, which was in good agreement with the predicted yield and higher than those of reflux and ultrasonic-assisted extraction methods. HPLC analysis indicated that the major polyphenols of apple pomace consisted of chlorogenic acid, caffeic acid, syrigin, procyanidin B2, (-)-epicatechin, cinnamic acid, coumaric acid, phlorizin and quercetin, of which procyanidin B2 had the highest content of 219.4 mg/kg. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Du L.-H.,Zhejiang University of Technology | Luo X.-P.,Zhejiang University of Science and Technology
RSC Advances | Year: 2012

The highly regioselective synthesis of sugar 6-monoesters with sugar and vinyl carboxylate in a flow microreactor using Lipozyme TL IM from Thermomyces lanuginosus as a catalyst has been developed. The important features of this method include mild reaction conditions, short reaction times (30 min), high yields and high regioselectivities. © 2012 The Royal Society of Chemistry.

Xiao Z.,Zhejiang University | Xia Y.,Zhejiang University of Technology | Ren Z.,Zhejiang University | Liu Z.,Zhejiang University | And 5 more authors.
Journal of Materials Chemistry | Year: 2012

In this work, single-crystalline α-FeOOH nanorods with a length of 400-700 nm and a diameter of 20-80 nm were successfully synthesized via a facile template-free hydrothermal method. Single-crystalline mesoporous α-Fe2O3 and Fe3O4 nanorods could be obtained from these α-FeOOH precursors after calcining at 350 °C in air and 500 °C in nitrogen, respectively. The as-prepared single-crystalline mesoporous α-Fe2O3 and Fe 3O4 nanorods exhibited a large specific surface area and porosity, effectively enhancing the electrochemical reaction area and accommodate the strain during the charge-discharge cycling process. © 2012 The Royal Society of Chemistry.

Xu L.,Zhejiang University of Technology
International Journal of Control, Automation and Systems | Year: 2011

In this paper, we study singularly perturbed impulsive stochastic delay differential systems (SPISDDSs). By establishing an L-operator delay differential inequality and using the stochastic analysis technique, we obtain some sufficient conditions ensuring the exponential p-stability of any solution of SPISDDSs for sufficiently small ε < 0. The results extend and improve the earlier publications. An example is also discussed to illustrate the efficiency of the obtained results. © ICROS, KIEE and Springer 2011.

Sun D.,Zhejiang University of Technology
Biochemical and Biophysical Research Communications | Year: 2016

Escherichia coli is naturally transformable, independent on the conserved DNA uptake machinery for single-stranded DNA (ssDNA) integration. The transfer of double-stranded DNA (dsDNA) during natural transformation of E. coli is regulated by the alternative sigma factor σS. However, it remains mysterious how dsDNA transfers across the membranes and how σS regulates natural transformation of E. coli. Here, I screened for σS-regulated genes for dsDNA transfer in E. coli. The screening identified the σS-regulated genes ydcS and ydcV, both locate on the putative ABC transporter ydcSTUV operon. Considering that ydcS and ydcV are predicted to encode a periplasmic protein and an inner membrane protein for substrate binding and translocation respectively, I propose that they may mediate dsDNA translocation across the inner membrane during natural transformation. In chemical transformation of E. coli, ydcS was but ydcV was not required. Thus, YdcV should not be the channel for dsDNA translocation in artificial transformation. Together with the previous observation that the outer membrane porin OmpA mediates dsDNA transfer across the outer membrane in chemical transformation but not in natural transformation, I conclude that dsDNA transfers across the two membranes through different routes in natural and artificial transformation of E. coli. © 2016 Elsevier Inc. All rights reserved.

Ma Z.,Shanghai JiaoTong University | Ma Z.,University College London | Chen Z.,Zhejiang University of Technology | Fanchini F.F.,Sao Paulo State University
New Journal of Physics | Year: 2013

In this paper, we present a measure of quantum correlation for a multipartite system, defined as the sum of the correlations for all possible partitions. Our measure can be defined for quantum discord (QD), geometric quantum discord or even for entanglement of formation (EOF). For tripartite pure states, we show that the multipartite measures for the QD and the EOF are equivalent, which allows direct comparison of the distribution and the robustness of these correlations in open quantum systems. We study dissipative dynamics for two distinct families of entanglement: a W state and a GHZ state. We show that, for the W state, the QD is more robust than the entanglement, while for the GHZ state, this is not true. It turns out that the initial genuine multipartite entanglement present in the GHZ state makes the EOF more robust than the QD. © IOP Publishing and Deutsche Physikalische Gesellschaft.

Shao Y.-H.,Zhejiang University of Technology | Deng N.-Y.,China Agricultural University
Neural Networks | Year: 2012

Twin support vector machines (TWSVMs) obtain faster learning speed by solving a pair of smaller SVM-type problems. In order to increase its efficiency further, this paper presents a coordinate descent margin based twin vector machine (CDMTSVM) compared with the original TWSVM. The major advantages of CDMTSVM lie in two aspects: (1) The primal and dual problems are reformulated and improved by adding a regularization term in the primal problems which implies maximizing the "margin" between the proximal hyperplane and bounding hyperplane, yielding the dual problems to be stable positive definite quadratic programming problems. (2) A novel coordinate descent method is proposed for our dual problems which leads to very fast training. As our coordinate descent method handles one data point at a time, it can process very large datasets that need not reside in memory. Our experiments on publicly available datasets indicate that our CDMTSVM is not only fast, but also shows good generalization performance. © 2011 Elsevier Ltd.

Liang C.,Zhejiang University of Technology | Liang C.,Zhejiang University | Gao M.X.,Zhejiang University | Pan H.G.,Zhejiang University | Liu Y.F.,Zhejiang University
Applied Physics Letters | Year: 2014

Phase transitions and energetic properties of Li2Mg(NH) 2 with different crystal structures are investigated by experiments and first-principles calculations. The Li2Mg(NH)2 with the primitive cubic and orthorhombic structure is obtained by dynamically dehydrogenating a Mg(NH2)2-2LiH mixture up to 280°C under an initial vacuum and 9.0bars H2, respectively. It is found that the obtained orthorhombic Li2Mg(NH)2 is converted to a primitive cubic structure as the dehydrogenation temperature is further increased to 400°C or performed by a 36h of high-energetic ball milling. Moreover, the primitive cubic phase can be converted to an orthorhombic phase after heating at 280°C under 9.0bars H2 for 1h. Thermodynamic calculations show that the orthorhombic phase is the ground state structure of Li2Mg(NH)2. The mechanism for phase transitions of Li 2Mg(NH)2 is also discussed from the angle of energy. © 2014 AIP Publishing LLC.

Long X.,Zhejiang University | Zhang G.,Zhejiang University of Technology | Shen C.,Zhejiang University | Sun G.,Sinopec | And 3 more authors.
Bioresource Technology | Year: 2013

Waste crude oil emulsion was inevitably produced in the petroleum industrial process, causing harmful impact on the ecological and social environment. In this study, rhamnolipid was for the first time investigated for demulsification of waste crude oil. As found in this paper, rhamnolipid treatment could obtain over 90% of dewatering efficiency on refractory waste crude oil and such efficient demulsification was confirmed on model emulsions. As further demonstrated on the pilot scale (100. L), rhamnolipid treatment could recover over 98% of crude oil from the wastes. The recovered oil contained less than 0.3% of water and thus can directly re-enter into refinery process while the aqueous phase can be disposed into dischargeable water due to largely reduced soluble COD after subjected to 5. days of active sludge treatment. It seems that rhamnolipids as biodemulsifiers were of great prospects in the industrial demulsification of waste crude oil. © 2012 Elsevier Ltd.

Zheng S.,Zhejiang University of Technology | Yu Q.,University of Nevada, Reno | Jiang Y.,University of Nevada, Reno
International Journal of Fatigue | Year: 2013

Mode I fatigue crack growth (FCG) experiments were carried out using extruded AZ31B magnesium alloy in ambient air. The cracks in the experiments using compact tension (CT) specimens were oriented in three different directions with respect to the extrusion direction. With constant load amplitude, the experiments were conducted with three load ratios (minimum load over maximum load in a loading cycle): 0.1, 0.5 and 0.75. The experimental results reveal that the specimen orientation has a significant influence on the FCG rate and crack path. Under the same load ratio and identical stress intensity factor range, the FCG rate of the T-L specimen is the highest while the L-T specimen shows the lowest value (L = extrusion direction, R = radial direction of the extrusion bar, T = direction perpendicular to the L-R plane). For the L-T specimens, a plateau of constant crack growth rate occurs after the threshold stage as crack extends. Typical macroscopic Mode I crack is developed in the T-L and T-R specimens whereas a deviation from the Mode I crack path and branching occur in the L-T specimens. For all three specimen orientations, the FCG rate increases with increasing load ratio. The values of the threshold stress intensity factor range are approximately the same for the L-T and T-L specimens and they are not significantly influenced by the load ratio. For the T-R specimens, the load ratio has a great effect on the threshold intensity. Transgranular cracking is the major cracking mode. Slip induced cleavage dominates the transgranular cracking in the T-L and L-T specimens whereas both twin boundary cracking and slip induced cleavage exist in the T-R specimens. © 2012 Elsevier Ltd. All rights reserved.

Fang K.,Harbin Institute of Technology | Yang J.G.,Zhejiang University of Technology | Liu X.S.,Harbin Institute of Technology | Song K.J.,Harbin Institute of Technology | And 2 more authors.
Materials and Design | Year: 2013

High-carbon steels which are transformed into extremely fine bainite plates embedded in a matrix of carbon-enriched austenite have recently been developed, and have found commercial application in the manufacture of engineering components. However, because of the large carbon concentration, they cannot be welded and this limits the scope for their exploitation. A method is reported here by which the mixture of bainitic ferrite and retained austenite is regenerated to prevent the austenite that is generated by the heat input during welding, from transforming into brittle martensite. The microstructures of the fusion and austenitised zones were characterised by X-ray diffraction, scanning electron microscopes and transmission electron microscopy. Tensile and micro-hardness tests were carried out to evaluate the mechanical properties. The results show that a bead-on-plate weld with the tensile strength of 1850. MPa and the hardness of 600. HV can in principle be been achieved; these properties almost match those of the base metal. © 2013 Elsevier Ltd.

Xiong Y.,Zhejiang University of Technology | Yu Q.,University of Nevada, Reno | Jiang Y.,University of Nevada, Reno
International Journal of Plasticity | Year: 2014

To experimentally study the role of the twinning/detwinning process in cyclic plastic deformation of Mg alloys, both strain-controlled and stress-controlled cyclic tension-compression experiments were conducted using extruded ZK60 magnesium (Mg) alloy in ambient air. The fully revered strain-controlled experiments had strain amplitudes varying from 0.25% to 4%. Three types of cyclic deformation are identified in light of the involvement of twinning/detwinning. The stress-controlled experiments reveal the cyclic ratcheting behavior of the material. Due to a strong basal texture of the material, no sustainable twinning/detwinning deformation occurs when the stress level is below the twinning or detwinning yield stress. As a result, ratcheting deformation under certain loading conditions is dominated by dislocation slip and is similar to that of other metallic materials. Cyclic twinning and detwinning in a stress-controlled experiment result in significant cyclic hardening. Under stress-controlled loading condition when ratcheting deformation occurs, the ratcheting rate decays with increasing number of loading cycles following a power law fashion regardless of the deformation mechanisms. Strain ratcheting is discussed for deformation involving the twinning/detwinning process and the experimental observations are explained in light of the micromechanisms. © 2013 Elsevier Ltd. All rights reserved.

Xiong Y.,Zhejiang University of Technology | Jiang Y.,University of Nevada, Reno
International Journal of Fatigue | Year: 2014

Uniaxial fatigue experiments were conducted on ZK60 magnesium (Mg) alloy in ambient air. They include fully reversed strain-controlled experiments with strain amplitudes ranging from 0.24% to 6.0%, strain-controlled experiments with a large compressive minimum strain of -9.4%, and stress-controlled experiments. For fully reversed strain-controlled experiments, fatigue process consists of crack initiation, small crack growth, and final failure in tension when the strain amplitude is lower than 3.0%. Final failure occurs under compression when the strain amplitude is larger than or equal to 3.5%, where the fracture surface shows characteristics identical to these observed from monotonic compression. A kink point corresponding to a strain amplitude of 0.35% is observed in the strain-life curve from the fully reversed strain-controlled fatigue experiments. This strain amplitude demarcates the influence of twinning-detwinning deformation on fatigue of the material. Asymmetric stress-strain hysteresis loops with a tensile mean stress are observed when the strain amplitude is larger than 0.35%. When the material is pre-compressed to -9.4%, the initial texture is changed from a strong basal texture to a strong (0001) or c-texture. The subsequent strain-controlled fatigue loading results in compressive mean stresses. The fatigue lives are similar to those of the basal textured state with identical strain amplitude for strain amplitudes larger than 0.4%. The Smith, Watson, and Topper fatigue parameter does not correlate the fatigue experiments with large compressive mean strains. © 2014 Elsevier Ltd. All rights reserved.

Li B.,Zhejiang University of Technology
Zhongguo Jiguang/Chinese Journal of Lasers | Year: 2012

Organic dyes such as vanadium (IV) oxo(phthalocyaninato) (VOPc) nanoparticles have been fabricated by pulse laser ablation in aqueous solution. Under the condition of the same total incident light energy, the average diameter of VOPc nanoparticles, observed by an atomic force microscopy (AFM), increases with the pulse laser energy density. The ultraviolet-visible light (UV-Vis) absorption spectrum of VOPc nanoparticles colloid solution indicates that there is no more contribution for producing nanoparticles by so longer laser irradiation time. The nanoparticles reaggregation directly influences the preparation efficiency and the size of the produced nanoparticles, and finally it will achieve dynamic equilibrium with the process of producing nanoparticles. In aqueous solution the hydrophobic force is the main reason for the nanoparticles reaggregation.

Li X.,Zhejiang University | Zhu Y.,Zhejiang University of Technology | Ling J.,Zhejiang University | Shen Z.,Zhejiang University
Macromolecular Rapid Communications | Year: 2012

Unmodified β-cyclodextrin has been directly used to initiate ring-opening polymerization of Ïμ-caprolactone in the presence of yttrium trisphenolate. Well-defined cyclodextrin (CD)-centered star-shaped poly(Ïμ-caprolactone)s have been successfully synthesized containing definite average numbers of arms (N arm = 4-6) and narrow polydispersity indexes (below 1.10). The number-average molecular weight (M̄ N, NMR) and average molecular weight per arm (M̄ n,arm) are controlled by the feeding molar ratio of monomer to initiator. The prepared star-PCL with M̄ n,NMR of 2.7 × 10 3 is in fully amorphous and that with M̄ n,NMR} $ of 13.3 × 10 3 is crystallized. In addition, the obtained poly(e-caprolactone) (PCL) stars with various molecular weights have different solubilities in methanol and tetrahydrofuran, which can be applied for further modifications. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Liu W.,Nanchang University | Liu J.,Zhejiang University of Technology | Li T.,Nanchang University | Liu C.,Nanchang University
Journal of Agricultural and Food Chemistry | Year: 2013

To improve lipid membrane stability and prevent leakage of encapsulated food ingredients, a polyelectrolyte delivery system (PDS) based on sodium alginate (AL) and chitosan (CH) coated on the surface of nanoliposomes (NLs) has been prepared and optimized using a layer-by-layer self-assembly deposition technique. Morphology and FTIR observation confirmed PDS has been successfully coated by polymers. Physical stability studies (pH and heat treatment) indicated that the outer-layer polymers could protect the core (NLs) from damage, and PDS showed more intact structure than NLs. Further enzymic digestion stability studies (particle size, surface charge, free fatty acid, and model functional component release) demonstrated that PDS could better resist lipolytic degradation and facilitate a lower level of encapsulated component release in simulated gastrointestinal conditions. This work suggested that deposition of polyelectrolyte on the surface of NLs can stabilize liposomal structure, and PDS could be developed as a formulation for delivering functional food ingredients in the gastrointestinal tract. © 2013 American Chemical Society.

Zhou H.-M.,Zhejiang University | Zhou H.-M.,China Jiliang University | Ou X.-W.,China Jiliang University | Xiao Y.,China Jiliang University | And 2 more authors.
Smart Materials and Structures | Year: 2013

Based on the equivalent circuit method, this paper adopts the nonlinear magnetostrictive constitutive relations to establish an analytical nonlinear magnetoelectric coefficient model for magnetostrictive/piezoelectric/ magnetostrictive laminated magnetoelectric composites. When the pre-stress is set to zero in the model, the predicted results of the magnetoelectric coefficient coincide well with the available experimental results both qualitatively and quantitatively. Using the model, we can qualitatively predict the influence of the pre-stress, magnetic bias fields and the volume fraction of the magnetostrictive material on the magnetoelectric coefficient. The predicted results show that the influences of the pre-stress on the magnetoelectric coefficient, which varies with the magnetic bias field, before and after reaching the magnetoelectric coefficient maximum, are opposite. That is, the influence of the pre-stress on curves of the magnetoelectric coefficient reverses when the magnetoelectric coefficient reaches its maximum. Therefore, the correct setting of the pre-stress can lower the applied magnetic bias field and improve the magnetoelectric coefficient. The established nonlinear magnetoelectric effect model can provide a theoretical basis for regulating the magnetoelectric coefficient by the pre-stress and magnetic bias field and make it possible to design high-precision miniature magnetoelectric devices. © 2013 IOP Publishing Ltd.

Chen L.,Zhejiang University of Technology
Zhejiang Daxue Xuebao (Gongxue Ban)/Journal of Zhejiang University (Engineering Science) | Year: 2011

As traditional least squares support vector machine(LSSVM) parameter selection using cross-validation is time-consuming, a city hourly water consumption forecasting method based on genetic algorithm(GA) and LSSVM was proposed. An autocorrelation method was used to analyze the hourly water consumption series according to the strong serial correlation. A self-adaptive binary GA was introduced to optimize the hyper-parameters of LSSVM, and the individual fitness values in GA were determined by cross-validation. Then a hourly water consumption forecasting model was built. Case study shows that the proposed hourly water consumption forecasting method based on GA and LSSVM has higher computing speed and better estimating performance than the traditional LSSVM-based method.

Li B.,Zhejiang University | Li B.,Zhejiang University of Technology | Liu Y.,Zhejiang University | Li C.,Zhejiang University | And 2 more authors.
Journal of Materials Chemistry A | Year: 2014

Lithium halides were introduced into the LiNH2-MgH2 system by ball milling the corresponding chemicals under 50 bar of H2 to decrease the dehydrogenation temperature and enhance the dehydrogenation kinetics. The results show that the LiNH2-MgH2-0.05LiBr sample exhibited optimal hydrogen storage performance. The onset dehydrogenation temperature of the LiNH2-MgH2-0.05LiBr sample was only 120 °C, which represents a 55 °C reduction with respect to that of the pristine LiNH2-MgH2 sample. The dehydrogenation rate of the LiNH2-MgH2 sample at 210 °C was increased threefold upon addition of LiBr, which is attributed to the reduction in the dehydrogenation activation energy. Moreover, the addition of LiBr could significantly suppress ammonia emission during the dehydrogenation process of the LiNH2-MgH2 sample. Structural examinations reveal that the added LiBr could react with LiNH2 to form Li7(NH 2)6Br during the dehydrogenation process. The in situ-formed Li7(NH2)6Br not only weakens the N-H bond but also promotes the migration of Li+, consequently improving the dehydrogenation kinetics of the LiNH2-MgH2 sample. © 2014 The Royal Society of Chemistry.

Li X.,CAS Nanjing Institute of Soil Science | Li X.,Zhejiang University of Technology | Wu Y.,CAS Nanjing Institute of Soil Science | Lin X.,CAS Nanjing Institute of Soil Science | And 2 more authors.
Soil Biology and Biochemistry | Year: 2012

The potential of mushroom cultivation substrate (MCS) in bioremediation was examined in polycyclic aromatic hydrocarbon (PAH)-contaminated soil. After a 60-day incubation, 32.9% dissipation of the 15 studied PAHs was observed in MCS-amended microcosms, with anthracene, benzo(a)pyrene and benzo(a)anthracene being the most degradable PAHs. MCS significantly increased the abundance and changed the community compositions of bacteria, fungi and aromatic hydrocarbon degraders. Two species belonging to the Sordariomycetes of the Ascomycota were enriched in all MCS-treated soil samples, and coupled with the unique changes in the PAH profile, this implies the involvement of laccase-like enzymes. Limited improvement was observed after adding Pleurotus ostreatus, possibly because of its poor colonization of the soil. In addition, alfalfa appeared to antagonize the bioremediation effects of MCS. The results of this study suggest that MCS can be a cost-effective and green biostimulation agent, thereby providing support for the development of MCS-based biostimulation of PAH-contaminated soil. © 2012 Elsevier Ltd.

Zhu Y.-H.,Zhejiang University of Technology | Leung V.C.M.,University of British Columbia
IEEE Transactions on Wireless Communications | Year: 2010

To achieve a long run-time for battery-operated portable electronic devices that incorporate wireless transceivers, efficient power management of the radio is a critical requirement. The power management function of IEEE 802.11 wireless local area networks (WLANs) allows stations (STAs) to operate in the doze mode so that their power consumption is significantly reduced. Hence, efficient algorithms to manage when and how often a STA enters and exits doze mode are crucial to battery-operated STAs. We address this problem by developing a novel model for stochastic analysis of timer-based power management in infrastructure IEEE 802.11 WLANs. Based on this model, the probabilities that a STA is active, idle, or dozing are derived, and the power consumption of the STA, number of frames buffered, and average delay per frame are obtained. These results enable an efficient power management algorithm that optimizes the idle timer and doze duration at the STA and the frame buffer at the access point. Moreover, similar statistics for the basic power management method in the IEEE 802.11 standard are derived as a special case of the proposed timer-based power management scheme. Numerical results are presented to demonstrate the effectiveness of the proposed algorithms. © 2006 IEEE.

Mei Z.,Huzhou University | Korotkova O.,University of Miami | Mao Y.,Huzhou University | Mao Y.,Zhejiang University of Technology
Optics Express | Year: 2015

We establish conditions under which a legitimate degree of coherence of a statistically stationary beam-like field raised to a power results in a novel legitimate degree of coherence. The general results and examples relate to scalar beams having uniform and non-uniform correlations. © 2015 Optical Society of America.

Mei Z.,Huzhou University | Mao Y.,Zhejiang University of Technology
Optics Express | Year: 2014

A class of electromagnetic sources with sinc Schell-model correlations is introduced. The conditions on source parameters guaranteeing that the source generates a physical beam are derived. The evolution behaviors of statistical properties for the electromagnetic stochastic beams generated by this new source on propagating in free space and in atmosphere turbulence are investigated with the help of the weighted superposition method and by numerical simulations. It is demonstrated that the intensity distributions of such beams exhibit unique features on propagating in free space and produce a double-layer flat-top profile of being shape-invariant in the far field. This feature makes this new beam particularly suitable for some special laser processing applications. The influences of the atmosphere turbulence with a non-Kolmogorov power spectrum on statistical properties of the new beams are analyzed in detail. ©2014 Optical Society of America.

Ren C.-X.,Sun Yat Sen University | Dai D.-Q.,Sun Yat Sen University | Li X.-X.,Sun Yat Sen University | Li X.-X.,Zhejiang University of Technology | Lai Z.-R.,Sun Yat Sen University
IEEE Transactions on Image Processing | Year: 2014

Face recognition with illumination or pose variation is a challenging problem in image processing and pattern recognition. A novel algorithm using band-reweighed Gabor kernel embedding to deal with the problem is proposed in this paper. For a given image, it is first transformed by a group of Gabor filters, which output Gabor features using different orientation and scale parameters. Fisher scoring function is used to measure the importance of features in each band, and then, the features with the largest scores are preserved for saving memory requirements. The reduced bands are combined by a vector, which is determined by a weighted kernel discriminant criterion and solved by a constrained quadratic programming method, and then, the weighted sum of these nonlinear bands is defined as the similarity between two images. Compared with existing concatenation-based Gabor feature representation and the uniformly weighted similarity calculation approaches, our method provides a new way to use Gabor features for face recognition and presents a reasonable interpretation for highlighting discriminant orientations and scales. The minimum Mahalanobis distance considering the spatial correlations within the data is exploited for feature matching, and the graphical lasso is used therein for directly estimating the sparse inverse covariance matrix. Experiments using benchmark databases show that our new algorithm improves the recognition results and obtains competitive performance. © 2013 IEEE.

Yao C.,University of Science and Arts of Iran | Yao C.,University College London | Ma Z.-H.,Shanghai JiaoTong University | Chen Z.-H.,Zhejiang University of Technology | Serafini A.,University College London
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012

We propose a robust and efficient approach for tripartite-to-bipartite entanglement localization. By using weak measurements and quantum measurement reversal, an almost maximal entangled state shared by two parties can be generated with the assistance of the third party by local quantum operations and classical communication from a W-like state. We show that this approach works well in the presence of losses and phase diffusion. Our method provides an active way to fight against decoherence, and might help for quantum communication and distributed quantum computation. © 2012 American Physical Society.

Xu Z.P.,University of Queensland | Zhang J.,Shanghai University | Adebajo M.O.,University of Queensland | Zhang H.,University of Queensland | Zhou C.,Zhejiang University of Technology
Applied Clay Science | Year: 2011

The review paper has briefly summarized the development of the use of layered double hydroxides (LDHs) and their derivatives as heterogeneous and recyclable catalysts/catalyst supports for various reactions in the period of 2005 to early 2010. The catalysis reactions involve a number of important fields, such as organic/pharmaceutical synthesis (e.g. the formation of several types of organic bonds), clean energy (e.g. the production of hydrogen and popular carbon nanotubes), and environmental pollution control (e.g. total decomposition of volatile organic compounds, photodecomposition of organic wastes, DeNOx and DeSOx). The authors have also commented on the state of the art of research and pointed out the potential future directions in developing LDH-based catalysts. This review has thus indicated that LDH-based catalysts are important materials useful in these fields and it is worthwhile making more efforts towards the development of LDH-based catalysts. © 2011 Elsevier B.V.

Zheng J.-J.,Zhejiang University of Technology | Dai J.-G.,Hong Kong Polytechnic University
Engineering Structures | Year: 2014

Fiber-reinforced polymer (FRP) rods have been increasingly used in grouted ground anchors due to their high strength-to-weight ratio, excellent corrosion resistance, and convenience in incorporating the fiber sensing technology. To establish their pull-out capacity, FRP rods are usually embedded within a grouted steel tube and then subjected to pull-out in the laboratory. The aim of this paper is to develop a numerical method for predicting the nonlinear pull-out response of FRP rods embedded in steel tubes filled with cement grout. In the method, the cement grout is assumed to be subject to simple shear, the local interfacial bond stress-slip model of the bar-to-grout interface is represented by a piece-wise curve comprising elastic, softening, and frictional stages, and the unloading effect is also taken into account. A set of two second-order ordinary differential equations are derived in terms of the displacements of the FRP rod and steel tube and solved analytically to formulate the element transfer matrix. When the thickness of the steel tube approaches infinity, this method can be applied to the problem of FRP rods embedded in rock. Based on the developed numerical method, the interfacial bond properties and snapback phenomenon are analyzed. After the method is validated by comparisons with four sets of experimental data, the effects of the radius and length of FRP rods, the local peak bond stress and the residual frictional strength on the maximum pull-out load are evaluated in a quantitative manner. © 2014 Elsevier Ltd.

Zheng Y.-J.,Zhejiang University of Technology | Ling H.-F.,PLA University of Science and Technology | Xue J.-Y.,Jiangxi Normal University
Computers and Operations Research | Year: 2014

Biogeography-based optimization (BBO) is a bio-inspired metaheuristic based on the mathematics of island biogeography. The paper proposes a new variation of BBO, named ecogeography-based optimization (EBO), which regards the population of islands (solutions) as an ecological system with a local topology. Two novel migration operators are designed to perform effective exploration and exploitation in the solution space, mimicking the species dispersal under ecogeographic barriers and differentiations. Experimental results show that the EBO outperforms the basic BBO and several other popular evolutionary algorithms (EAs) on a set of well-known benchmark problems. We also present a real-world application of the proposed EBO to an emergency airlift problem in the 2013 Ya'an-Lushan Earthquake, China. © 2014 The Authors.

Janjua M.R.S.A.,University of Sargodha | Mahmood A.,University of Sargodha | Ahmad F.,Zhejiang University of Technology
Canadian Journal of Chemistry | Year: 2013

In this research paper, we have reported solvent effects on nonlinear optical properties of tetrammineruthenium(II) complexes of modified 1,10-phenanthrolines. Polarizability and hyperpolarizability were calculated in the gas phase, benzene (ε = 2.3), THF (ε = 7.52), dichloromethane (ε = 8.93), acetone (ε = 21.01), methanol (ε = 33.00), acetonitrile (ε = 36.64), and water (ε = 80.10) using density functional theory. These solvents cover a wide range of polarities. The results of theoretical investigation have shown that nonlinear optical properties significantly increased with the increase of solvent polarity. Solvent strongly affected hyperpolarizability as compared with polarizability. Nonlinear optical properties were also changed by the change of functional. Hyperpolarizability significantly changed with the change of functional as compared with polarizability. The results of this study indicate that like structural modification, polarity of the medium can significantly change the nonlinear optical properties. © 2013 Published by NRC Research Press.

Wu H.X.,Hangzhou Dianzi University | Luo H.Z.,Zhejiang University of Technology | Yang J.F.,Hangzhou Dianzi University
Journal of Global Optimization | Year: 2014

This paper aims at showing that the class of augmented Lagrangian functions for nonlinear semidefinite programming problems can be derived, as a particular case, from a nonlinear separation scheme in the image space associated with the given problem. By means of the image space analysis, a global saddle point condition for the augmented Lagrangian function is investigated. It is shown that the existence of a saddle point is equivalent to a regular nonlinear separation of two suitable subsets of the image space. Without requiring the strict complementarity, it is proved that, under second order sufficiency conditions, the augmented Lagrangian function admits a local saddle point. The existence of global saddle points is then obtained under additional assumptions that do not require the compactness of the feasible set. Motivated by the result on global saddle points, we propose two modified primal-dual methods based on the augmented Lagrangian using different strategies and prove their convergence to a global solution and the optimal value of the original problem without requiring the boundedness condition of the multiplier sequence. © 2013 Springer Science+Business Media New York.

Huang Y.,Zhejiang University of Technology
Applied Mechanics and Materials | Year: 2014

Since CASSANDRA-I was successfully produced by Wang Shoujue in 1995, In this paper, we analysis its the learning method of the semiconductor neurocomputer, and apply the semiconductor neurocomputer CASSANDRA- I I to face recognition. The satisfactory performance is obtained through experiment results. © (2014) Trans Tech Publications, Switzerland.

Li B.,Zhejiang University of Technology
Gaodeng Xuexiao Huaxue Xuebao/Chemical Journal of Chinese Universities | Year: 2013

The organic optoelectronic device consisting of lithium phthalocyanine (LiPc) thin film as active layer with the structure of indium tin oxide/poly(3, 4-ethylenedioxythiophene):poly(styrenesulfonate)/lithium phthalocyanine/polyvinylidene fluoride/aluminum (ITO/PEDOT:PSS/LiPc/PVDF/Al) was fabricated by spin coating and vacuum deposition methods. The photocurrent polarities of the device under the irradiation of visible and infrared pulse laser were investigated, respectively. Under the irradiation of 532 nm pulse laser the photocurrent direction of the device in the external circuit is from ITO to Al, but the photocurrent polarity will reverse by the irradiation of 1064 nm pulse laser, namely, photocurrent direction is from Al to ITO in the external circuit. The absorption spectrum of LiPc thin film indicates its broad absorption in visible and infrared region and it belongs to x-form confirmed by X-ray diffraction. The ambipolar property of LiPc radical could vary with the wavelength of incident light, which induces the above phenomena. It will have potential applications in light controllable switch and infrared light detection.

Liu H.-S.,Zhejiang University of Technology | Lu H.,Beijing Normal University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2014

We show that for n-dimensional Einstein gravity coupled to a scalar field with mass-squared m02=-n(n-2)/(4ℓ2), the first law of thermodynamics of (charged) AdS black holes will be modified by the boundary conditions of the scalar field at asymptotic infinity. Such scalars can arise in gauged supergravities in four and six dimensions, but not in five or seven. The result provides a guiding principle for constructing designer black holes and solitons in general dimensions, where the properties of the dual field theories depend on the boundary conditions. © 2014 The Authors.

Chen B.,Donghua University | Lu S.-X.,Donghua University | Li C.-H.,Donghua University | Kang Q.-S.,Donghua University | And 2 more authors.
Journal of Hazardous Materials | Year: 2011

The influence of the initial fuel temperature on the burning behavior of n-heptane pool fire was experimentally studied at the State Key Laboratory of Fire Science (SKLFS) large test hall. Circular pool fires with diameters of 100. mm, 141. mm, and 200. mm were considered with initial fuel temperatures ranging from 290. K to 363. K. Burning rate and temperature distributions in fuel and vessel wall were recorded during the combustion. The burning rate exhibited five typical stages: initial development, steady burning, transition, bulk boiling burning, and decay. The burning rate during the steady burning stage was observed to be relatively independent of the initial fuel temperature. In contrast, the burning rate of the bulk boiling burning stage increases with increased initial fuel temperature. It was also observed that increased initial fuel temperature decreases the duration of steady burning stage. When the initial temperature approaches the boiling point, the steady burning stage nearly disappears and the burning rate moves directly from the initial development stage to the transition stage. The fuel surface temperature increases to its boiling point at the steady burning stage, shortly after ignition, and the bulk liquid reaches boiling temperature at the bulk boiling burning stage. No distinguished cold zone is formed in the fuel bed. However, boiling zone is observed and the thickness increases to its maximum value when the bulk boiling phenomena occurs. © 2011 Elsevier B.V.

Nie R.,Zhejiang University | Shi J.,Zhejiang University | Xia S.,Zhejiang University | Shen L.,Zhejiang University of Technology | And 3 more authors.
Journal of Materials Chemistry | Year: 2012

Rod-like MnO 2 uniformly attached on both side of GO sheets (MnO 2/GO) is an efficient heterogeneous catalyst for the synthesis of primary amides from primary alcohols and ammonia as well as from aldehydes or nitriles. Water is the best solvent for these reactions, analytically pure crystals of product could be isolated by simply cooling in ice and this catalyst has excellent recyclability. © 2012 The Royal Society of Chemistry.

Li B.,Zhejiang University of Technology
Wuli Huaxue Xuebao/ Acta Physico - Chimica Sinica | Year: 2012

The ferroelectric thin film of lead magnesium niobate-lead titanate (PMN-PT) was fabricated and characterized using UV-Vis transmission spectroscopy, X-ray diffraction (XRD), and atomic force microscopy (AFM). To determine the photocurrent properties of the bulk hetero junction organic blend film a photovoltaic device with the structure of tin indium oxide (ITO)/PMN-PT/organic blend film /aluminum (Al)was fabricated. Under modulated laser irradiation the amplitude and polarity of the transient photocurrent varied with the bias voltage, which shows that the photocurrent polarity of a conventional bulk hetero junction organic photovoltaic device is determined by the internal electric field that is induced by the difference between the work function of the anode and cathode electrodes. A new method is proposed for investigating the photocurrent properties of bulk hetero junction organic photovoltaic devices. © Editorial office of Acta Physico-Chimica Sinica.

Wang D.,CAS Institute of Software | Zhang Y.,CAS Institute of Software | Chen S.,Zhejiang University of Technology
Mathematical Problems in Engineering | Year: 2013

This paper designs a tangible programming tool, E-Block, for children aged 5 to 9 to experience the preliminary understanding of programming by building blocks.With embedded artificial intelligence, the tool defines the programming blocks with the sensors as the input and enables children to write programs to complete the tasks in the computer.The symbol on the programming block's surface is used to help children understanding the function of each block. The sequence information is transferred to computer by microcomputers and then translated into semantic information.The systemapplies wireless and infrared technologies and provides user with feedbacks on both screen and programming blocks. Preliminary user studies using observation and user interview methods are shown for E-Block's prototype. The test results prove that E-Block is attractive to children and easy to learn and use. The project also highlights potential advantages of using single chip microcomputer (SCM) technology to develop tangible programming tools for children. Copyright © 2013 DanliWang et al.

Tao S.,Zhejiang University of Technology | Yumei Y.,Shanghai Research Institute of Building Sciences
Advances in Cement Research | Year: 2015

This paper reports on the characterisation and quantitative analysis of ettringite in the hydration products of several high-alite cements. The study has three main parts: (a) the investigation of the microscopic morphology of ettringite; (b) an X-ray diffraction characterisation; and (c) a quantitative analysis of the ettringite in the hardened cement pastes. The results show that the ettringite could be selectively extracted by an ethylene glycol/methanol solvent with a volume ratio of 1:3, which thereby proved to be an effective method for the quantitative analysis of ettringite. Combined with the results of the X-ray diffraction analysis, the formation and transformation mechanisms of ettringite could be characterised and described in more detail. During the 90-d aging period, the reaction degree of the coal gangue was higher than that of fly ash and had a greater impact on the formation and transformation of ettringite. The amount of ettringite formed from the hydration of coal gangue cement was higher than that from neat Portland cement, whereas the amount of ettringite formed from the hydration of fly ash cement was lower than that from neat Portland cement.

Kang F.,Dalian University of Technology | Li J.,Dalian University of Technology | Liu S.,Zhejiang University of Technology
Mathematical Problems in Engineering | Year: 2013

This paper proposes a damage detection method based on combined data of static and modal tests using particle swarm optimization (PSO). To improve the performance of PSO, some immune properties such as selection, receptor editing, and vaccination are introduced into the basic PSO and an improved PSO algorithm is formed. Simulations on three benchmark functions show that the new algorithm performs better than PSO. The efficiency of the proposed damage detection method is tested on a clamped beam, and the results demonstrate that it is more efficient than PSO, differential evolution, and an adaptive real-parameter simulated annealing genetic algorithm. Copyright © 2013 Fei Kang et al.

Xue Y.-L.,Jiangsu University | Zhang Y.-G.,Shandong Academy of Sciences | Liu X.-H.,Zhejiang University of Technology
Asian Journal of Chemistry | Year: 2012

A cyclopropane derivative, 1-cyano-N-(2,4-dichlorophenyl) cyclopropanecarboxamide (C11H8N2OCl2) was synthesized and its structure was studied by X-ray diffraction, FTIR, 1H NMR, MS and elemental analysis. The crystals are monoclinic, space group C2 with a = 14.387(9), b = 6.926(4), c = 12.237(7) A°, a = 90.00, b = 100.386(10), g = 90.00°, V = 1199.4(12) A°3, Z = 4, F(000) = 520, Dc = 1.413 g/cm3, μ = 0.520 cm-1, the final R = 0.0603 and wR = 0.1653. A total of 2976 reflections were collected, of which 1134 were independent (Rint = 0.0381). The preliminary biological test showed that the synthesized compound is bioactive against the KARI of Escherichia coli.

Song X.C.,Fujian Normal University | Zheng Y.F.,Zhejiang University of Technology | Ma R.,Fujian Normal University | Zhang Y.Y.,Fujian Normal University | Yin H.Y.,Hangzhou Dianzi University
Journal of Hazardous Materials | Year: 2011

The Mo-doped Bi 2WO 6 three-dimensional (3D) hierarchical microspheres from nanoplates have been synthesized by a hydrothermal route. The products were characterized in detail by multiform techniques: X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDS), scanning electron microscopy (SEM), and UV-vis absorption spectrum. The results of the photocatalytic degradation of Rhodamine-B (RhB) in aqueous solution showed that molybdenum ions doping greatly improved the photocatalytic efficiency of Bi 2WO 6 3D hierarchical microspheres. The Mo-doped Bi 2WO 6 microspheres with atomic ratio of Mo-W of 0.05 had the best activity in photodegradation of RhB in aqueous solution under 500W Xe lamp light irradiation. © 2011 Elsevier B.V.

Zhou Y.,North China Institute of Aerospace Engineering | Zhu J.,Zhejiang University of Technology
Composite Structures | Year: 2016

The third-order shear deformation plate theory is utilized to analyze the vibration and bending of the simply-supported magneto-electro-elastic rectangular plates. The obtained analytical solution is valid for both thick and thin plates, and for arbitrary variation of material properties in the thickness direction. The natural frequencies obtained by the present study are proved to be identical with available results provided in references, which validates and verifies our formulation and programming. Parametric studies are completed for varying material gradient profile and length-to-thickness ratios. Analyses for forced vibrations and static bending of a multiferroic plate with a sinusoidal spatial variation of the pressure applied on its top surface complete the paper. © 2016 Elsevier Ltd

Shen C.,Zhejiang University | Zhang G.,Zhejiang University of Technology | Meng Q.,Zhejiang University
Biochemical Engineering Journal | Year: 2010

Various mechanisms are involved in drug hepatotoxicity including reactive intermediates, steatosis, phospholipidosis, mitochondrial dysfunction, etc. Although 3D cultured hepatocytes reflected more CYP 450 mediated reactive intermediates than traditional 2D cultured hepatocytes, the 3D model has not been evaluated for drug-induced phospholipidosis. This study applied 3D cultured hepatocytes in gel entrapment for drug-induced phospholipidosis, and amiodarone was used as a model drug. By amiodarone exposure for 48 h, 3D cultured hepatocytes showed large number of lysosomal lamellar bodies (indicating phospholipidosis) and toxic response at a low dose of 2.5 μM, equivalent to toxic serum concentration in rats. This sensitivity to amiodarone-induced phospholipidosis might relate to the more intracellular drug distribution in 3D cultured hepatocytes. Moreover, steatosis, mitochondrial injury and oxidative stress were all sensitively detected in 3D cultured hepatocytes, well reflecting the involvement of these mechanisms in amiodarone hepatotoxicity. In addition, pretreatment of 3D cultured hepatocytes by CYP 3A1/2 inhibitor (ketoconazole) significantly reduced the toxicity of amiodarone, indicating the positive mediation of CYP 3A1/2. By comparison, 2D cultured hepatocytes did not show significant phospholipidosis and involvement of CYP 3A1/2. In conclusion, hepatocytes in 3D culture well reflected amiodarone toxicity and thus could be a promising model for phospholipidosis study. © 2010 Elsevier B.V. All rights reserved.

Long X.,Zhejiang University | Meng Q.,Zhejiang University | Zhang G.,Zhejiang University of Technology
Journal of Membrane Science | Year: 2014

Membrane fouling was inevitable in the ultrafiltration process in dairy industry, causing harsh reduction of the membrane performance. The current cleaning agents like acid/base and chemical surfactants would be limitedly used in future due to their detrimental effect on membrane or/and environment/health. In this study, the environmental-friendly biosurfactant rhamnolipid was for the first time applied to clean the ultrafiltration membrane fouled by protein. The cleaning by rhamnolipid under pH 9 could largely remove the foulant from the PSU, PAN and PEG-g-PSU membranes and restore the water flux to about 94% of the initial level, performing much better than the flux recovery of 50-70% for Tween 20 and SDS, the most extensively used surfactants in membrane cleaning. Moreover, rhamnolipid exhibited superior properties over the commonly used cleaner of sodium hydrate (NaOH) and even the commercial membrane cleaner in view of cleaning efficiency and operation mildness. Finally, rhamnolipid was demonstrated to be effective in cleaning the long-term fouling membrane. Taken together, rhamnolipid as an economical product of lowly costive cell-free broth shows great potential in industrial application as membrane cleaner. © 2014.

Chen L.,Zhejiang University of Technology | Wu F.,Intertek
Journal of Saudi Chemical Society | Year: 2014

Fluorinated acrylate latex was successfully prepared by semi-continuous seeded emulsion polymerization of dodecafluoroheptyl methacrylate (DFMA) with butyl acrylate (BA), methyl methacrylate (MMA) initiated by potassium persulfate in the water. The resultant latexes and their films are characterized with Fourier transform infrared (FTIR) spectrometry, contact angle determinator, dynamic light scattering detector and surface tension determinator. Effect of different surfactants on colloidal and polymer properties of fluorinated acrylate latex was studied. Results show that the latex prepared with sodium dodecyl benzene sulfonate surfactant has the smallest particle size and contact angle but the moderate surface tension. The latex prepared with perfluorooctanesulfonic acid potassium surfactant has the smallest surface tension, moderate particle size but the biggest contact angle. The latex prepared with sodium 2-hydroxy-3-(methacryloyloxy) prop- ane-1-sulfonate surfactant has the biggest particle size and surface tension but moderate contact angle. In addition, the latex prepared with sodium 2-hydroxy-3-(methacryloyloxy) prop- ane-1-sulfonate has higher electrolyte stability. © 2011.

Xue Y.-L.,Jiangsu University | Zhang Y.-G.,Shandong Academy of Sciences | Liu X.-H.,Zhejiang University of Technology
Asian Journal of Chemistry | Year: 2012

A cyclopropane derivative, 1-cyano-N-(4-bromophenyl)cyclopropanecarboxamide (C11H9N2OBr) was synthesized and its structure was studied by X-ray diffraction, FTIR, 1H NMR spectrum and MS. The crystal is triclinic, space group P-1 with α = 8.902(4), β = 10.944(5), c = 12.733(6) Å, α = 103.753(8), β = 106.812(9), γ = 104.004(9)°, V = 1087.1(9) Å3, Z = 4, F(000) = 528, Dc = 1.620 g/cm 3, the final R = 0.0604 and wR = 0.1197. A total of 5404 reflections were collected of which 3790 were independent (Rint = 0.0578). There are two intramolecular hydrogen bonds in the crystal lattice. The preliminary biological test showed that the synthesized compound had weak activity against the KARI of Escherichia coli.

Hu F.,Zhejiang Shuren University | Hu F.,Zhejiang University of Technology
Journal of Information and Computational Science | Year: 2013

A robotic eye-to-hand coordination technology was put forward based on depth camera and Bursa coordinate transformation model. This technology employed the Zhang Zhengyou's calibration method to get intrinsic parameters of the depth camera and RGB camera, employed the triangulation measuring principles of infrared camera and infrared laser projector to get in-depth information of target, employed the imaging model of camera to finally get the coordinates of target in the coordinate system of camera, then described the relationship between camera coordinate system and world coordinate system of robot with Bursa model and finally solved the parameters of Bursa model with the indirect adjustment function model. It was demonstrated in the experiment that this simple and convenient hand-eye technology could carry out vision guiding tasks effectively. © 2013 Binary Information Press.

Hu B.,Zhejiang University of Technology | Hu B.,University of Nebraska - Lincoln | Dimagno S.G.,University of Nebraska - Lincoln
Organic and Biomolecular Chemistry | Year: 2015

Nitrogen heterocycles are abundant in natural products and pharmaceuticals. An emerging interest among synthetic chemists is to apply vinyl azides as a pivotal three-atom synthon for the construction of structurally complex and diverse N-heterocyclic skeletons. The unique features of the azide group connected to an alkene moiety permit vinyl azides to function as electrophiles, nucleophiles, or radical acceptors; their access to diverse reaction pathways provides great opportunities to generate highly reactive intermediates with often unusual or unconventional reactivities. This tutorial review will systematically illustrate the reactivities of vinyl azides and describe recent breakthroughs in the development of new transformations that create N-heterocycles. This journal is © The Royal Society of Chemistry 2015.

Song X.-R.,Lanzhou University | Xia X.-F.,Lanzhou University | Song Q.-B.,Zhejiang University of Technology | Yang F.,Lanzhou University | And 4 more authors.
Organic Letters | Year: 2012

An efficient and selective gold-catalyzed cascade reaction for the synthesis of oxanorbornenes and naphthalene derivatives from easily prepared hydroxy enynes has been developed. Divergent products could be obtained from the same substrates by different gold catalytic systems. © 2012 American Chemical Society.

Wang Z.,Zhejiang University | Wang Z.,Changzhou University | Mo H.,Zhejiang University | Cheng D.,Zhejiang University | And 2 more authors.
Organic and Biomolecular Chemistry | Year: 2012

Dehydrogenative cross-coupling reaction of primary anilines, secondary anilines, carboxamides, and sulfonamides with 1,3-diarylpropenes to form a series of allylic amines promoted by DDQ have been realized. Both monoallylation and diallylation products can be selectively synthesized when primary anilines are used as the starting materials. The method may provide a wide scope of allylamines in scientific research including biologically active compound library construction. This journal is © 2012 The Royal Society of Chemistry.

Lin K.,Zhejiang University of Technology | Gan J.,University of California at Riverside
Chemosphere | Year: 2011

Presence of pharmaceuticals at trace levels in recycled water is an emerging issue impacting the beneficial reuse of treated wastewater, including practices such as irrigation and groundwater recharge in arid and semi-arid regions. To assess the environmental risks of irrigation with recycled water containing such micropollutants, in this study we evaluated sorption and degradation of five pharmaceuticals that are antibiotic and anti-inflammatory drugs in two soils collected from arid regions. Naproxen and trimethoprim showed moderate to strong sorption, while the sorption of diclofenac, ibuprofen and sulfamethoxazole was negligible in both soils. Under aerobic conditions, the studied compounds were susceptible to microbial degradation with half-lives varying from 4.8 to 69.3. d. Apart from sulfamethoxazole, the other compounds were relatively persistent under anaerobic conditions as indicated by a negligible loss over 84. d of incubation or half-lives >50. d. The degradation of the selected pharmaceuticals was influenced by microbial activities, oxygen status in the soil, soil type and compound characteristics. The poor sorption and relative persistence of diclofenac and ibuprofen under anaerobic conditions suggest that the two chemicals may pose a high leaching risk when using recycled for irrigation or groundwater replenishment. © 2010 Elsevier Ltd.

Su L.,Nankai University | Su L.,Zhejiang University of Technology | Zhong Y.,Nankai University | Zhou Z.,Nankai University
Journal of Materials Chemistry A | Year: 2013

The conversion reaction mechanism has widely been accepted in interpreting and evaluating the lithium storage capability of transition metal oxides (MOs). However, this mechanism cannot well explain the phenomenon of the extra capacity which exists in almost all MO materials and attracts much attention. Up to now, the extra capacity phenomenon has generally been ascribed to the reversible conversion of polymeric gel-like films. However, the essential role of metal nanoparticles in this process has not been systematically investigated. To further illustrate the role of metal nanoparticles for the extra capacity, Fe3O4@C and Fe@C monodispersed hierarchical core-shell microspheres were designed and adopted as the case study. Naturally Fe 3O4@C composites exhibited a large Li storage capacity beyond its theoretical value. However, Fe@C microspheres, which are usually regarded to be inert for lithium storage, still presented a certain electrochemical capacity. Fe nanoparticles might serve as electrocatalysts for the reversible conversion of some components of solid electrolyte interface films, and bring extra capacity to Fe3O4 and electrochemical capacity to Fe. This study can enlighten us for the exploiting of advanced active materials and electrolytes for Li ion batteries, and new energy storage devices. © 2013 The Royal Society of Chemistry.

Xia Z.,Zhejiang University of Technology
Mathematical Methods in the Applied Sciences | Year: 2014

In this paper, we propose a new class of functions called pseudo S-asymptotically ω-periodic function in the Stepanov sense and explore its properties in Banach spaces including composition results. Furthermore, the existence and uniqueness of the pseudo S-asymptotically ω-periodic mild solutions to Volterra integro-differential equations is investigated. Applications to integral equations arising in the study of heat conduction in materials with memory are shown. © 2014 John Wiley & Sons, Ltd.

Jin X.,Zhejiang University of Technology
2011 International Conference on Computer Science and Service System, CSSS 2011 - Proceedings | Year: 2011

Watermarking provides an efficient method for copyright protection. This paper discusses the digital watermark technology which is based on Arnold and wavelet transform. After the Arnold transform of embedded watermark information, then embeds it into host gray images with discrete wavelet transform. Emulational experiments are done in Matlab, Experimental results demonstrate that this watermarking algorithms have better effect: The watermark is invisible and robust against kinds of classical attacks. © 2011 IEEE.

Zhang X.,Wenzhou University | Zhang X.,CAS Institute of Automation | Hu W.,CAS Institute of Automation | Chen S.,Zhejiang University of Technology | Maybank S.,Birkbeck College
IEEE Transactions on Industrial Electronics | Year: 2014

Object tracking is viewed as a two-class 'one-versus-rest' classification problem, in which the sample distribution of the target over a short period of time is approximately Gaussian while the background samples are often multimodal. Based on these special properties, we propose a graph-embedding- based learning method, in which the topology structures of graphs are carefully designed to reflect the properties of the sample distributions. This method can simultaneously learn the subspace of the target and its local discriminative structure against the background. Moreover, a heuristic negative sample selection scheme is adopted to make the classification more effective. In applications to tracking, the graph-embedding-based learning is incorporated into a Bayesian inference framework cascaded with hierarchical motion estimation, which significantly improves the accuracy and efficiency of the localization. Furthermore, an incremental updating technique for the graphs is developed to capture the changes in both appearance and illumination. Experimental results demonstrate that, compared with the two state-of-the-art methods, the proposed tracking algorithm is more efficient and effective, particularly in dynamically changing and cluttered scenes. © 1982-2012 IEEE.

Wang Y.,University of Sichuan | Pan X.,Dalian University of Technology | Chen Y.,Zhejiang University of Technology | Gu X.,University of Sichuan
Scientometrics | Year: 2013

In this study, we empirically investigate the role of references in patents in a firm's technological learning and innovation when the patents are transferred (i. e., technology licensing activities) to these firms. This study is based on a sample of 68 Chinese high-tech firms that engaged in patent technology licensing while using a matching sample of non-licensee firms, and it examines covered patents in licensee agreements that were originally registered in the European Patent Office between 2000 and 2005. Empirical results indicate that the reference scope (defined as the number of different patent classes-classes that the examined patent does not belong to-in the backward citations) and the time lag of the backward citations each has a positive effect and a negative effect on the licensee firms' innovation outcomes respectively, measured as the number of Chinese patent applications during the 5 years after the licensing year. However, it failed to find a positive effect of the science-based citations (defined as backward citations to journal articles) as we predicted. © 2013 Akadémiai Kiadó, Budapest, Hungary.

Zhou Y.,Jiangxi University of Science and Technology | Hu X.,Zhejiang University of Technology | Xiao Y.,Jiangxi University of Science and Technology | Shu Q.,Jiangxi University of Science and Technology
Electrochimica Acta | Year: 2013

Hollow mesoporous tungsten trioxide microsphere (HMTTS) was synthesized by spay drying methodand Pt/HMTTS were prepared and used as new electrocatalyst for methanol oxidation. The structureof HMTTS and Pt/HMTTS was characterized with scanning electron microscopy (SEM), tunnel electronmicroscopy (TEM) and X-ray diffraction (XRD), and its electrocatalytic activity toward methanol oxida-tion was investigated with cyclic voltammetry (CV) and chronoamperometry (CA). The characterizationsfrom SEM, TEM and XRD show that the platinum particles with an average size of 5 nm have been suc-cessfully distributed on the surface of HMTTS. Cyclic voltammetry and chronoamperometry indicate thatPt/HMTTS catalyst exhibits higher electrocatalytic activity and good stability during methanol oxidationin comparison to Pt/C and Pt/WO3catalysts.

Shen C.,Zhejiang University | Chen H.,Zhejiang University | Wu S.,Zhejiang University | Wen Y.,Zhejiang University | And 4 more authors.
Journal of Hazardous Materials | Year: 2013

Metal-biopolymer complexes has recently gained significant attention as an effective adsorbent used for the removal of Cr(VI) from water. Unfortunately, despite increasing research efforts in the field of removal efficiency, whether this kind of complex can reduce Cr(VI) to less-toxic Cr(III) and what are the mechanisms of detoxification processes are still unknown. In this study, despite the highly adsorption efficiency (maximum adsorption capacity of 173.1. mg/g in 10. min), the significant improvement of Cr(VI) reduction by chitosan-Fe(III) complex compared with normal crosslinked chitoan has been demonstrated. In addition, the structure of chitosan-Fe(III) complex and its functional groups concerned with Cr(VI) detoxification have been characterized by the powerful spectroscopic techniques X-ray absorption fine structure (XAFS) and X-ray photoelectron spectroscopy (XPS). The XPS spectra indicated that the primary alcoholic function on C-6 served as an electron donor during Cr(VI) reduction and was oxidized to a carbonyl group. The X-ray adsorption near edge spectra (XANES) of the Cr(VI)-treated chitosan-Fe(III) complex revealed the similar geometrical arrangement of Cr species as that in Cr(III)-bound chitosan-Fe(III). Overall, a possible process and mechanism for highly efficient detoxification of Cr(VI) by chitosan-Fe(III) complex has been elucidate. © 2012 Elsevier B.V.

Zhu J.,Zhejiang University of Technology
Advanced Materials Research | Year: 2011

With the rapid development of wireless mobile communicational technology and the growing demand for lifelong education, mobile education has become a convenient and effective way of education and received considerable attention and research. To further meet the needs of study at "any time, anywhere, any style" for teachers and solve the problem that the difficulty of continuing education and training of in-service teachers, this paper uses the wireless communicational technology of 3G to create the platform for teachers' training by the main mobile terminals of mobile phone. It will promote the better service under the concept of mobile learning and it has great significance for solving the problems in the traditional training and supporting teachers to enhance the professional development.

Fang Z.,Zhejiang University of Technology
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2010

The study presents a novel quantum immune algorithm (QIA) for solving the parallel machine scheduling in the textile manufacturing industry. In this proposed algorithm, there are distinct characteristics as follows. First, the encoding method is based on Q-bit representation. Second, a novel mutation operator with a chaos-based rotation gate is proposed. Most importantly, two diversity schemes, suppression algorithm and similarity-based truncation algorithm, are employed to preserve the diversity of the population, and a new selection scheme is proposed to create the new population. Simulation results show that QIA is better than two quantum-inspired evolutionary algorithms. © 2010 Springer-Verlag.

Wen X.,Zhejiang University of Technology
Synlett | Year: 2012

(A) Instead of the traditional palladium-catalyzed Wacker oxidation, Itoh and co-workers3 have reported an one-pot synthetic protocol of acetophenones from styrenes with molecular iodine, visible light and oxygen. Regardless of various substituents at the aromatic ring, the corresponding acetophenones could be obtained in moderate to good yields. This procedure involves aerobic photooxidation and deiodination in one pot and provides the first report of metal-free direct syntheses of acetophenones from styrenes. (B) By employing catalytic amount (10 mol%) of I 2 and [hydroxy( tosyloxy)iodo]benzene (HTIB, Koser's reagent), Giannis et al.4 have described a new and efficient synthetic method for diverse tetrahydrofuran derivatives. Compared to the previous systems such as Pd(II)/DIB5 or NaIO4/NaHSO3,6 the present methodology exhibits obvious advantages; it is a one-step, metal-free and simple operation and has also great applicability in the synthesis of biologically active natural products. (C) Iodine-induced regioselective C-C and C-N bond forming reactions of N-protected indole derivatives were reported by Liang and co-workers.7 Compared with the transition-metal-catalyzed crosscouplings requiring noble metal catalysts and high loading of metal oxidants, the novel coupling method has shown great potential for both industrial and academic purposes. (D) Nicholas and co-workers8 have disclosed an I 2-catalyzed aminosulfonating system for a broad range of benzylic and some types of saturated hydrocarbons utilizing imido-iodinanes (PhI = NSO2Ar) as aminosulfonating reagent. It was worth to mention that the reaction was highly regioselective for the tertiary C-H of adamantine with no secondary C-H aminated product detected. While in some previous reported transition-metal-catalyzed systems,9 the regioselectivity was relatively poor and the ratio of tertiary to secondary aminated products was 3-15:1. (E) Mao et al.10 have found that the transition-metal-catalyzed Suzuki coupling could also be well performed in air using iodine as effective catalyst. In addition, the newly developed metal-free protocol was also applicable for the coupling of (E)-β-bromostyene with phenylboronic acid, with retention of the double bond geometry. (F) Benzimidazole is an important chemical entity in pharmaceuticals due to its structural similarity to purine. In order to obtain this useful reagent, Lin et al.11 have developed an efficient method for the conversion of unprotected and unmodified aldoses into aldobenzimidazoles and aldo-naphthimidazoles using iodine as oxidant. A series of mono-, di-, and trialdoses containing carboxyl and acetamido groups were introduced into the reaction given the desired products in high yields. Notably, no cleavage of the glycosidic bond occurred under such mild reaction conditions. (G) Molecular iodine can also be used for deprotection. Konwar and co-workers12 found that the I 2/SDS/water system could transform a broad range of oximes and imines to the corresponding carbonyl compounds with moderate to good yields under neutral conditions. it was found that the catalytic amount of I 2 could promote the reaction in the presence of surfactant (SDS), meanwhile, no formation of iodoxime/imidoyl iodide or over-oxidized products (acids) were observed during the reaction. © Georg Thieme Verlag Stuttgart. New York.

Liu X.-H.,Zhejiang University of Technology | Zhao W.-G.,Nankai University | Wang B.-L.,Nankai University | Li Z.-M.,Nankai University
Research on Chemical Intermediates | Year: 2012

A series of novel 1,2,3-thiadiazole derivatives were designed and synthesized. Their structures were characterized by 1H NMR, MS and HRMS. The bioactivity tests indicated that compound 9b exhibits a favorable KARI inhibition rate, and some of these novel compounds also showed moderate herbicidal activity against Brassica campestris. © Springer Science+Business Media B.V. 2012.

Hu Q.,Zhejiang University of Technology
Mathematical Problems in Engineering | Year: 2013

An ultradeep foundation pit is a complex system composed of a retaining structure, foundation soil, and groundwater. Design and construction of foundation pits for use at greater depths than in the past require continual improvement in the design methods and analysis methods applied. In this paper, a load-deformation analysis model of a retaining structure based on a bearing-mode analysis of an ultra-deep foundation pit is proposed. A calculation method was theoretically derived for the horizontal foundation stiffness coefficient for this model, and the influences of factors such as space size, stress path, load level, and seepage were analyzed. A numerical example and a case study of an ultra-deep foundation pit in the Hangzhou Metro Line number 1 test section are presented. The calculated results for deformation of the structure and for earth pressure were found to be similar to the results obtained from elastic-plastic finite element analysis and similar to the measured results. The results of this study indicate that the proposed analysis model adequately reflects the force-deformation characteristics of an ultra-deep foundation pit and show that the proposed analysis model appropriately considers the influences of various factors. © 2013 Qi Hu.

Wang A.,Zhejiang University of Technology | Wang A.,Baylor University
Physical Review Letters | Year: 2013

Stationary, axisymmetric, and slowly rotating vacuum spacetimes in the Hořava-Lifshitz (HL) gravity are studied, and it is shown that, for any given spherical static vacuum solution of the HL theory (of any model, including the ones with an additional U(1) symmetry), there always exists a corresponding slowly rotating, stationary, and axisymmetric vacuum solution, which reduces to the former, when the rotation is switched off. The rotation is universal and only implicitly depends on the models of the HL theory and their coupling constants through the spherical seed solution. As a result, all asymptotically flat slowly rotating vacuum solutions are asymptotically identical to the slowly rotating Kerr solution. This is in contrast to the claim of Barausse and Sotiriou, in which slowly rotating black holes were reported (incorrectly) not to exist in the infrared limit of the nonprojectable HL theory. © 2013 American Physical Society.

Cao H.,Nanjing College of Chemical Technology | Wang R.,Zhejiang University of Technology
Advanced Materials Research | Year: 2013

A quantitative structure-property relationship (QSPR) model for prediction of standard net heat of combustion (ΔHc°) was developed based on the ant colony optimization (ACO) method coupled with the partial least square (PLS) for variable selection. For developing this model, a diverse set of 1650 organic compounds were used, and 1481 molecular descriptors were calculated for every compound. Four molecular descriptors were screened out as the parameters of the model, which was finally constructed using multi-linear regression (MLR) method. The squared correlation coefficient R2 of the model was 0.995 for the training set of 1322 compounds. For the test set of 328 compounds, the corresponding R2 was 0.996. The results of this study showed that an accurate prediction model for ΔHc° could be obtained by using the ant colony optimization method. Moreover, this study can provide a new way for predicting the ΔHc° of organic compounds for engineering based on only their molecular structures. © (2013) Trans Tech Publications, Switzerland.

Li J.,Zhejiang University of Technology | Chen Y.,Nanjing University of Science and Technology
Optics and Laser Technology | Year: 2012

Based on the theory of paraxial electromagnetic beams in anisotropic medium, propagation properties of a linearly polarized confluent hypergeometric (HyG) beam through uniaxial crystals orthogonal to the optical axis are investigated. Analytical expressions are derived for the resultant optical field components. Effects of separate beam parameters together with the ratio of refractive indices of crystals on transversal intensity distributions are revealed by numerical calculations, respectively. It is shown that the beam profile finally converts into an elliptical shape due to influences of anisotropic crystals. Moreover, it is also indicated that through suitable selection of parameters, types of the optical vortices of resultant field would change from a central dark spot to a slight dark ring or an axial shadow during the propagation. These numerical results may provide alternative advantages to the trapping of tiny particles by utilizing HyG beams in practical experiments. © 2011 Elsevier Ltd. All rights reserved.

Zheng J.-J.,Zhejiang University of Technology | Zhang J.,Princeton University | Scherer G.W.,Princeton University
Cement and Concrete Research | Year: 2012

This paper presents a computer simulation method for predicting the degree of hydration at the initial setting time of cement paste with particle agglomeration. Agglomeration is controlled by using a square-well potential for the interaction between two cement particles, and the degree of hydration at the initial setting time is determined using the burning algorithm. It is verified that, when the critical surface-to-surface distance for attachment is taken as 0.05 μm, the simulation predictions are in good agreement with experimental results. For cement particles in water at the initial stage of hydration, the number of clusters obeys the power law with an average Fisher exponent of 1.9. Finally, the effects of key factors affecting the degree of hydration at the initial setting time are quantitatively evaluated. © 2012 Elsevier Ltd. All rights reserved.

Wang P.,Zhejiang University of Technology
AIP Advances | Year: 2012

In this paper we study the time evolution of an observable in the interacting fermion systems driven out of equilibrium. We present a method for solving the Heisenberg equations of motion by constructing excitation operators which are defined as the operators  satisfying [ Ĥ, Â] = λ Â. It is demonstrated how an excitation operator and its excitation energy λ can be calculated. By an appropriate supposition of the form of  we turn the problem into the one of diagonalizing a series of matrices whose dimension depends linearly on the size of the system.We perform this method to calculate the evolution of the creation operator in a toy model Hamiltonian which is inspired by the Hubbard model and the nonequilibrium current through the single impurity Anderson model. This method is beyond the traditional perturbation theory in Keldysh-Green's function formalism, because the excitation energy λ is modified by the interaction and it will appear in the exponent in the function of time.© Copyright 2012 Author(s).

Jiang B.,Zhejiang University | Wang N.,Zhejiang University | Wang L.,Zhejiang University of Technology
International Journal of Hydrogen Energy | Year: 2014

Solid oxide fuel cell (SOFC) has been widely recognized as one of the most promising fuel cells. The SOFC performance is highly influenced by several parameters associated with the internal multi-physicochemical processes. In this work, the optimal modeling strategy is designed to determine the parameters of SOFC using a simple and efficient barebone particle swarm optimization (BPSO) algorithm. The cooperative coevolution strategy is applied to divide the output voltage function into four subfunctions based on the interdependence among variables. To the nonlinear characteristic of SOFC model, a hybrid learning strategy is proposed for BPSO to ensure a good balance between exploration and exploitation. The experimental results illustrate the effectiveness of the proposed algorithm. The comparisons also indicate that cooperative coevolution strategy and hybrid learning improve the performance of original PSO algorithm, offering better approximation effect and stronger robustness. Copyright © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Nie R.,Zhejiang University | Shi J.,Zhejiang University | Du W.,Zhejiang University | Ning W.,Zhejiang University of Technology | And 2 more authors.
Journal of Materials Chemistry A | Year: 2013

A sandwich-like N-doped graphene/Co3O4 hybrid was prepared via a simple one-pot hydrothermal reaction in a solution of NH 3. Characterizations disclosed that highly dispersed Co 3O4 nanoparticles with dominant exposed {112} and {110} planes were fabricated on both sides of well-exfoliated N-doped graphene; N-dopants in the graphene matrix can prevent re-graphitization of graphene, strengthen the interaction between Co3O4 and the graphene matrix, and improve the dispersion of Co3O4. This hybrid (Co3O4/RGO-N) exhibited superior activity and stability for the epoxidation of styrene compared to bulk Co3O 4 and N-free graphene supported Co3O4. At the same time, the resulting catalyst also showed high compatibility with various olefins and alcohols with good conversion and high selectivity. This synergistic strategy can provide simple, efficient and versatile blue-prints for low-cost fabrication of graphene-based nanocomposites for extending applications where graphene has rarely been exploited and beyond. © 2013 The Royal Society of Chemistry.

Zhang Y.,CAS Shanghai Institutes for Biological Sciences | Xu Y.-H.,Zhejiang University of Technology | Yi H.-Y.,CAS Shanghai Institutes for Biological Sciences | Gong J.-M.,CAS Shanghai Institutes for Biological Sciences
Plant Journal | Year: 2012

The plant vacuole is an important organelle for storing excess iron (Fe), though its contribution to increasing the Fe content in staple foods remains largely unexplored. In this study we report the isolation and functional characterization of two rice genes OsVIT1 and OsVIT2, orthologs of the Arabidopsis VIT1. Transient expression of OsVIT1:EGFP and OsVIT2:EGFP protein fusions revealed that OsVIT1 and OsVIT2 are localized to the vacuolar membrane. Ectopic expression of OsVIT1 and OsVIT2 partially rescued the Fe2+- and Zn2+-sensitive phenotypes in yeast mutant Δccc1 and Δzrc1, and further increased vacuolar Fe2+, Zn2+ and Mn2+ accumulation. These data together suggest that OsVIT1 and OsVIT2 function to transport Fe2+, Zn2+ and Mn 2+ across the tonoplast into vacuoles in yeast. In rice, OsVIT1 and OsVIT2 are highly expressed in flag leaf blade and sheath, respectively, and in contrast to OsVIT1, OsVIT2 is highly responsive to Fe treatments. Interestingly, functional disruption of OsVIT1 and OsVIT2 leads to increased Fe/Zn accumulation in rice seeds and a corresponding decrease in the source organ flag leaves, indicating an enhanced Fe/Zn translocation between source and sink organs, which might represent a novel strategy to biofortify Fe/Zn in staple foods. © 2012 Blackwell Publishing Ltd.

Liang H.,Peking University | Sun W.,Peking University | Jin X.,Peking University | Li H.,Peking University | And 4 more authors.
Angewandte Chemie - International Edition | Year: 2011

Pores for thought: The pore size and pore shape (including "rectangular", triangular, tetragonal, diamond, pentagonal, and hexagonal) in binary molecular porous networks formed by trimesic acid (TMA) and 4,4′-bis(4-pyridyl)biphenyl (BPBP) molecules on Au(111) is tuned simply through changing the TMA:BPBP ratio (see picture). Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chen S.Y.,Zhejiang University of Technology | Li Y.F.,City University of Hong Kong
IEEE Sensors Journal | Year: 2011

Estimation of the blurring effect is very important for many imaging systems. This letter reports an idea to efficiently and robustly compute the blurring parameter on certain stripe edges. Two formulas are found to determine the degree of imaging blur only by calculating the area sizes under the corresponding profile curves, without the need for deconvolution or transformation over the image. The method can be applied to many applications such as vision sensing of scene depth. A 3-D vision system is taken as an implementation instance. © 2010 IEEE.

Huang Z.,Zhejiang University of Technology | Du X.,Zhejiang University of Science and Technology
Habitat International | Year: 2015

Improving public housing allocation efficiency and residential satisfaction is the key to the better realization of the social inclusion goals. We assess residential satisfaction with public housing and examine its determinants, based on the Hangzhou public housing household survey. We found that neighborhood environment, public facilities and housing characteristics are the main factors that influence residential satisfaction. Public housing allocation scheme, social environment and residence comparison also have influences. Among the four types of public housing, cheap rental housing has the highest residential satisfaction, followed by public rental and monetary subsidized housing, while economic comfortable housing has the lowest residential satisfaction. The residents in public rental and monetary subsidized housing pay more attention to the neighborhood environment, residents in cheap rental housing are more concerned about the housing and neighborhood characteristics, and economic comfortable housing residents care more about the neighborhood characteristics and public facilities. Therefore, the government should not only improve the physical environment of public housing, but also the public housing allocation scheme and social environment. The different needs of public housing residents should also be considered to improve residential satisfaction and the allocation efficiency of public housing. © 2015 Elsevier Ltd.

Zhou X.,Zhejiang University of Technology | Li Y.,City University of Hong Kong | He B.,Fuzhou University | Bai T.,Pacific Advanced Technology
IEEE Transactions on Industrial Informatics | Year: 2014

Tracking multiple moving targets in a video is a challenge because of several factors, including noisy video data, varying number of targets, and mutual occlusion problems. The Gaussian mixture probability hypothesis density (GM-PHD) filter, which aims to recursively propagate the intensity associated with the multi-target posterior density, can overcome the difficulty caused by the data association. This paper develops a multi-target visual tracking system that combines the GM-PHD filter with object detection. First, a new birth intensity estimation algorithm based on entropy distribution and coverage rate is proposed to automatically and accurately track the newborn targets in a noisy video. Then, a robust game-theoretical mutual occlusion handling algorithm with an improved spatial color appearance model is proposed to effectively track the targets in mutual occlusion. The spatial color appearance model is improved by incorporating interferences of other targets within the occlusion region. Finally, the experiments conducted on publicly available videos demonstrate the good performance of the proposed visual tracking system. © 2012 IEEE.

Sun L.,Zhejiang University of Technology | Reed M.R.,University of Kentucky
American Journal of Agricultural Economics | Year: 2010

This paper evaluates agricultural trade creation and diversion effects of the most important free trade agreements (FTAs). Trade creation and diversion effects are estimated using a Poisson Pseudo- Maximum-Likelihood (PPML) estimator with various fixed effects to deal with heteroskedasticity and zero trade observations.The analysis finds that PPML estimation is preferred to OLS and the estimated impacts of FTAs are different if zero trade observations are considered. The ASEAN-China preferential trade agreement, EU-15, EU-25, and Southern African Development Community agreements have generated large increases in agricultural trade among their members. © The Author (2010).

Liu M.,Zhejiang University of Technology | Liu M.,Hohai University | Gao Y.,Hohai University | Liu H.,Hohai University
International Journal for Numerical and Analytical Methods in Geomechanics | Year: 2014

A new elastoplastic model is developed for rockfills within the general critical state framework incorporating the state parameter. Two state functions are proposed to characterize the evolution of volume dilation and strain softening of rockfills, and a modified breakage index based on the concept of Hardin's relative breakage is defined to describe the progressive crushing of rockfills. The nonassociated plastic flow rule is derived from a state dependent dilatancy equation, and it incorporates energy dissipation due to intrinsic nonlinear friction and particle breakage upon shearing. Thus, their couple effect on the plastic deviatoric and volumetric deformation of rockfills is taken into account in the current model. The numerical analyses are carried out for a series of drained triaxial tests on the modeled rockfills at various consolidation pressures and stress paths. The volume dilation/contraction and strain softening/hardening of rockfills are accurately predicted by the proposed model, and the particle breakage and nonlinear critical state shear strength of rockfills are also well captured. The research findings indicate that the current model is applicable to represent the complex stress-strain-volume change behavior of rockfills in general. © 2013 John Wiley & Sons, Ltd.

Zheng D.,Zhejiang University of Technology
Color Research and Application | Year: 2015

Fabric color design is a complex process in textiles and clothing industry. A new method for fabric color selection and transferring is proposed in this study. An automatic way to select the colors from the natural images is developed for fabric color design. Based on these colors, a fabric image is then used for color transferring. The fabric image is processed by a bias field estimation operation, and the membership function of the color deviations of the image has been obtained. According to the selected colors and the color membership function, the fabric image colors can be changed and transferred to a new image that preserves the similar texture appearance but with significantly different color effects. The experimental results confirm the effectiveness of the proposed method. © 2014 Wiley Periodicals, Inc. Col Res Appl, 40, 304-310, 2015 © 2014 Wiley Periodicals, Inc.

Chen L.,Zhejiang University of Technology | Wu F.,Intertek
Journal of Applied Polymer Science | Year: 2012

Self crosslinking fluorinated acrylic latex (SCLFAL) has been successfully prepared via starved seeded semibatch emulsion polymerization of butyl acrylate (BA), methyl methacrylate (MMA), 2-(perfluoro-(1,1-bisisopropyl)-2-propenyl) oxyethyl methacrylate (POMA), and N-methylolacrylamide (NMA). The resultant SCLFAL is characterized by Fourier transform infrared (FTIR) spectrometry and nuclear magnetic resonance (NMR). Influences of the added amount of NMA on the crosslinking degree, contact angle, particle size, and glass transition temperature (T g) of the film are investigated. Results show that the crosslinking degree, contact angle, and T g of the film can be improved when the moderate amount of NMA is introduced into the mixed monomers. However, the added amount of NMA has no marked effect on the particle size of SCLFAL. © 2011 Wiley Periodicals, Inc.

Lu X.-M.,China Institute of Technology | Lu P.-Z.,Zhejiang University of Technology | Zhang H.,China Institute of Technology
Applied Microbiology and Biotechnology | Year: 2014

Pyrosequencing-based analysis was used to characterize and compare bacterial communities in manure samples of piglets (GSPM) and adult pigs (GBPM) bred with green feeds without additives, and piglets (ASPM) and adult pigs (ABPM) bred with synthetic feeds containing additives. For each sample, 5,010 effective sequences were selected and utilized to do the bacterial composition analysis, respectively. In total, 1,489, 1,327, 941, and 883 operational taxonomic units were obtained at 5 % distance cutoff in GBPM, GSPM, ABPM, and ASPM, respectively. Bacterial phylotype richness in GBPM was higher than the other samples, and ASPM had the least richness. The most dominant class in the four samples is Bacteroidia. Approximately 41 % sequences in GBPM were affiliated with the Clostridiales order. Campylobacter, Clostridium and Streptococcus genera containing pathogenic bacteria were detected in the four samples. Bacterial diversity and abundance in swine manures varied with piglets, adult pigs, and feeds. In the four samples, higher bacterial diversity but less potentially pathogenic bacterial genera in manures of adult pigs bred with green feeds were found, which indicated that those manures were more suitable for resource utilization. This study also provides evidence for the reasonableness of pig farming with green feeds. © 2013 Springer-Verlag.

Pan J.X.,Zhejiang University of Technology
Advanced Materials Research | Year: 2014

In recent years, with the development of video surveillance systems, the cluster and load balancing technology need be applied to improve the system performance and the quality of service. In this paper, on the basis of common load balancing algorithms, considering the characteristics of the video surveillance system, design a new load balancing scheduling mechanism, by improving the weighted round robin algorithm and introducing the nodes cooperation strategy. The testing results show that the new mechanism can distribute the loads more reasonably and make use of the server resources more effectively. © (2014) Trans Tech Publications, Switzerland.

Gao J.,Zhejiang University of Technology
Computers and Industrial Engineering | Year: 2010

This study presents a novel artificial immune system for solving a multiobjective scheduling problem on parallel machines (MOSP), which has the following characteristics: (1) parallel machines are nonidentical, (2) the type of jobs processed on each machine can be restricted, and (3) the multiobjective scheduling problem includes minimizing the maximum completion time among all the machines (makespan) and minimizing the total earliness/tardiness penalty of all the jobs. In this proposed algorithm, the cells are represented by a vector group, and a local search algorithm is incorporated to facilitate the exploitation of the search space. Specially, a new diversity technique is proposed to preserve the diversity of the population and enhance the exploration of the solution space. Simulation results show the proposed algorithm outperforms the vector immune genetic algorithm (VIGA). © 2010 Elsevier Ltd. All rights reserved.

Liu J.,Zhejiang University | Xiong H.-N.,Zhejiang University of Technology | Song F.,Zhejiang University | Wang X.,Zhejiang University
Physica A: Statistical Mechanics and its Applications | Year: 2014

Taking into account the density matrices with non-full ranks, we show that the fidelity susceptibility is determined by the support of the density matrix. Combining with the corresponding expression of the quantum Fisher information, we rigorously prove that the fidelity susceptibility is proportional to the quantum Fisher information. As this proof can be naturally extended to the full rank case, this proportional relation is generally established for density matrices with arbitrary ranks. Furthermore, we give an analytical expression of the quantum Fisher information matrix, and show that it can also be represented in the density matrix's support. © 2014 Elsevier B.V. All rights reserved.

Yi T.-F.,Anhui University of Technology | Yi T.-F.,Harbin Institute of Technology | Yi T.-F.,Chilwee Power Co. | Yang S.-Y.,Anhui University of Technology | And 4 more authors.
Journal of Power Sources | Year: 2014

The spinel Li4Ti5O12 has been doped by Na for the purpose of improving its cycle performance as an anode. The lattice parameter of Li4Ti5O12 increases due to the Na doping. SEM shows that all materials are well crystallized with a particle size in the range of 400-600 nm. The pristine Li4Ti5O 12 sample has a bigger particle size than that of Na-doped samples. Although the doping does not change the crystallographic structure of Li 4Ti5O12, they exhibit better cyclability at high charge-discharge rate compared with pristine Li4Ti 5O12. Li3.85Na0.15Ti 5O12 gives the best cycling performance, only 11.1% loss of capacity after 80 cycles at 2 C charge-discharge rate. Na-doped Li 4Ti5O12 exhibits lower potential separation, indicating faster electron transfer kinetics and cycling reversibility. Electrochemical impedance spectroscopy demonstrates that the improved performance of the Na-doped Li4Ti5O12 is due to a small decrease in the charge transfer resistance, indicating high electrochemical activity during cycling. The excellent cycling and safety performance of the Na-doped Li4Ti5O12 electrodes are found to be due to the significantly increased ionic and electronic conductivity. Since fast charge-discharge performance is an important factor that needs to be considered in fabricating power batteries in industry, the Na-doped Li4Ti5O12 materials moves closer to real and large scale applications. © 2013 Elsevier B.V. All rights reserved.

Liu H.-S.,Zhejiang University of Technology | Lu H.,Beijing Normal University
Journal of High Energy Physics | Year: 2014

We consider the subset of gauged maximal supergravities that consists of the SO(n + 1) gauge fields Aij and the scalar deformation T ij of the Sn in the spherical reduction of M-theory or type IIB. We focus on the Abelian Cartan subgroup and the diagonal entries of Tij . The resulting theories can be viewed as the STU models with additional hyperscalars. We find that the theories with only one or two such vectors can be generalized naturally to arbitrary dimensions. The same is true for the D = 4 or 5 Einstein- Maxwell theory with such a hyperscalar. The gauge fields become massive, determined by stationary points of the hyperscalars a la the analogous Abelian Higgs mechanism. We obtain classes of Lifshitz and Schrö;dinger vacua in these theories. The scaling exponent z turns out to be rather restricted, taking fractional or irrational numbers. Tweaking the theories by relaxing the mass parameter or making a small change of the superpotential, we find that solutions with z = 2 can emerge. In a different application, we find that the resolution of superstar singularity in the STU models by using bubbling-AdS solitons can be generalized to arbitrary dimensions in our theories. In particular, we obtain the smooth AdS solitons that can be viewed as the resolution of the Reissner-Nordstrøm superstars in general dimensions. © 2014 The Authors.

Yang H.,Zhejiang University of Technology
Procedia Environmental Sciences | Year: 2011

Fast determination of growing stages and harvest time of fruits and vegetables is necessary to implement robotic operation for horticulture automation. This study evaluates the feasibility of using visible-near-infrared (Vis-NIR) spectroscopy to nondestructively determine the harvest time of tomatoes. A mobile, fibre-type, AgroSpec VIS-NIR spectrophotometer (Tec5, Germany) with a spectral range of 350-2200nm, was used for spectral acquisition of tomatoes in reflection mode. A new index was used to measure the growing stages of tomatoes. Tomato plants were provided by Silsoe Horticultural Center, Bedfordshire, United Kingdom. Spectra were divided into a calibration set (70%) and an independent validation set (30%). Calibration set were subjected to a partial least squares regression (PLSR) with leave-one-out cross validation to establish calibration models respectively based on different spectral ranges, e.g., VIS(400-760nm), NIR(760-2100nm) and VIS-NIR(400-2100nm). Prediction performance of these models on the independent validation set indicates that PLSR models based on entire spectral range (VIS-NIR) outperform those based on partial spectral ranges (VIS or NIR). Coupled with appropriate spectral transformation, the PLSR models can achieve excellent prediction performance of harvest time of tomatoes with coefficient of determination (R 2) of 0.89 and RPD of 3.00. It is concluded that VIS-NIR spectroscopy combined with optimized PLSR models for GS prediction can be successfully adopted as a remote sensing technique for predicting harvest time of tomatoes, which allows for implementing autonomous fruit-picking robots. © 2011 Published by Elsevier Ltd.

Liu H.-S.,Zhejiang University of Technology | Lu H.,Beijing Normal University | Pope C.N.,Texas A&M University | Pope C.N.,University of Cambridge
Journal of High Energy Physics | Year: 2014

We study static spherically-symmetric solutions of the Einstein-Proca equations in the presence of a negative cosmological constant. We show that the theory admits solutions describing both black holes and also solitons in an asymptotically AdS background. Interesting subtleties can arise in the computation of the mass of the solutions and also in the derivation of the first law of thermodynamics. We make use of holographic renormalisation in order to calculate the mass, even in cases where the solutions have a rather slow approach to the asymptotic AdS geometry. By using the procedure developed by Wald, we derive the first law of thermodynamics for the black hole and soliton solutions. This includes a non-trivial contribution associated with the Proca "charge". The solutions cannot be found analytically, and so we make use of numerical integration techniques to demonstrate their existence. © 2014 The Author(s).

Tan D.,Tsinghua University | Tan D.,Zhejiang University of Technology | Wu Q.,Tsinghua University | Chen J.-C.,Tsinghua University | Chen G.-Q.,Tsinghua University
Metabolic Engineering | Year: 2014

The halophile Halomonas TD01 and its derivatives have been successfully developed as a low-cost platform for the unsterile and continuous production of chemicals. Therefore, to increase the genetic engineering stability of this platform, the DNA restriction/methylation system of Halomonas TD01 was partially inhibited. In addition, a stable and conjugative plasmid pSEVA341 with a high-copy number was constructed to contain a LacIq-Ptrc system for the inducible expression of multiple pathway genes. The Halomonas TD01 platform, was further engineered with its 2-methylcitrate synthase and three PHA depolymerases deleted within the chromosome, resulting in the production of the Halomonas TD08 strain. The overexpression of the threonine synthesis pathway and threonine dehydrogenase made the recombinant Halomonas TD08 able to produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate) or PHBV consisting of 4-6mol% 3-hydroxyvalerate or 3HV, from various carbohydrates as the sole carbon source. The overexpression of the cell division inhibitor MinCD during the cell growth stationary phase in Halomonas TD08 elongated its shape to become at least 1.4-fold longer than its original size, resulting in enhanced PHB accumulation from 69wt% to 82wt% in the elongated cells, further promoting gravity-induced cell precipitations that simplify the downstream processing of the biomass. The resulted Halomonas strains contributed to further reducing the PHA production cost. © 2014 International Metabolic Engineering Society.

Wu D.,Zhejiang University | Wu D.,Ruian Institute of Testing for Quality and Technical Supervision | Cao X.,Zhejiang University of Technology | Wu S.,Zhejiang University
Journal of Chromatography A | Year: 2012

Counter-current chromatography (CCC) is extremely useful for the separation, purification, and isolation of natural products. Recently, Berthod et al.. [4,5] established an elution-extrusion CCC method in metabolic analysis by combining regular chromatographic elution with stationary-phase extrusion, which extends the hydrophobicity window of a counter-current separation. In this study, a novel overlapping elution-extrusion CCC method was developed and applied to the preparation of natural cytotoxic andrographolides from the aerial parts of. Andrographis paniculata, a well-known Traditional Chinese Medicine (TCM) with potent anti-inflammatory effect and anti-cancer activity. Its theory was first developed, and then a series of CCC experiments were performed to investigate the efficiency of the method in the separation of the ethanol extracts from. A. paniculata. Results show that overlapping elution-extrusion CCC is an efficient method to prepare a cytotoxic natural diterpenoid combination of 14-deoxy-andrographolide and 14-deoxy-11,12-didehydroandrographolide with the molar ratio of 1:2 as well as andrographolide using an optimized solvent system composed of hexane-ethyl acetate-ethanol-water (5:5:4:6, v/v) with an on-demand solvent preparation mode. All components obtained showed potent cytotoxic activity against human hepatocellular liver carcinoma cells HepG2 and doxorubicin-resistant R-HepG2 cells. Molecular structures have been identified by electrospray ionization mass spectrometry (ESI-MS), electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS), one- and two-dimensional nuclear magnetic resonance (1D- and 2D-NMR). The method appears to be very useful for the high-throughput purification of natural products. © 2011 Elsevier B.V..

Zhu O.,Zhejiang University of Technology | Zhan R.,National University of Singapore | Liu B.,National University of Singapore
Macromolecular Rapid Communications | Year: 2010

Herein we describe a novel and simple conjugated polymer-fluorescent probe based platform for trypsin detection from protein mixtures in homogeneous solution. This platform takes advantage of specific interaction between the probe and the active site of trypsin and the electrostatic interaction between the polymer and the protein to mediate energy transfer between the polymer and the probe. This method does not require any separation steps, which should facilitate high-throughput protease screening and drug discovery. (Figure Presented) © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Yuan W.-B.,Zhejiang University of Technology | Kim B.,University of Plymouth | Li L.-Y.,University of Plymouth
Journal of Constructional Steel Research | Year: 2014

The majority of the existing literature on castellated members is focused on beams. Very little work has been done on the stability of castellated columns although they have been increasingly used in buildings in recent years. This paper presents a new analytical solution for calculating the critical buckling load of simply supported castellated columns when they buckle about the major axis. This analytical solution takes into account the influence of web shear deformations on the buckling of castellated columns and is derived using the stationary principle of potential energy. The formula derived for calculating the critical buckling load is demonstrated for a wide range of section dimensions using the data obtained from finite element analyses published by others. It was found that the influence of web shear deformations on the critical buckling loads of castellated columns increased with the cross-sectional area of a tee section and the depth of web opening, but decreased with the length and the web thickness of the column. It is shown that the inclusion of web shear deformations significantly reduces the buckling resistance of castellated columns. Neglecting the web shear deformations could overestimate the critical buckling load by up to 25%, even if a reduced second moment of area is used. © 2013 Elsevier Ltd.

Zhang J.,Zhejiang University of Technology
Applied Mechanics and Materials | Year: 2014

China has become the largest manufacturer and exporter in the global clothing market with cost advantages. Given the intensification of global competition, it is crucial to assess the present status and international competitiveness of Chinese clothing industry. This paper makes a quantitative analysis on the international competitiveness of Chinese clothing industry by using trade competitiveness index and revealed comparative advantage index. Moreover, based on an in-depth analysis of the influencing factors, this paper puts forward some measures to enhance the international competitiveness of Chinese clothing industry. © (2014) Trans Tech Publications, Switzerland.

Liu X.-F.,Ningbo University of Technology | Liu X.-H.,Zhejiang University of Technology
Acta Crystallographica Section E: Structure Reports Online | Year: 2011

The title compound C7H5N3S2, occurs as the thione tautomer in the solid state; the dihedral angle between the pyridine and thiadiazole ring planes is 2.08 (6)°. In the crystal, molecules are linked by N - H⋯N hydrogen bonds, generating C(8) chains propagating in [010].

Shen C.,Zhejiang University | Wen Y.,Zhejiang University | Shen Z.,Zhejiang University of Technology | Wu J.,Hangzhou Normal University | Liu W.,Zhejiang University
Journal of Hazardous Materials | Year: 2011

A facile and green approach that improves the catalytic lifetime of cobalt tetrasulfophthalocyanine (CoTSPc) for the degradation of dyes is presented. Structurally ordered mesoporous silicas (MCM-41, MCM-48 and SBA-15), microporous aluminosilicates (ZSM-5) and macroporous alumina (γ-Al 2O 3) with different pore sizes were selected for the immobilization of CoTSPc, and a wide range of pH conditions (pH values from 4 to 12) were tested with the CoTSPc immobilization procedure. In the catalytic oxidation study, CoTSPc that was immobilized to MCM-41 silica (CoTSPc@MCM-41) prepared at a pH of 12 showed the longest catalytic lifetime. The TOC removal and discoloration of C. I. Acid Red 73 was approximately 60% and 82%, respectively, in the presence of CoTSPc@MCM-41 with H 2O 2 after 3h. These results indicate that MCM-41, which has a matching size between its mesopores (30Å) and CoTSPc molecules (25Å), can prevent CoTSPc molecules from aggregating and improve its catalytic lifetime. In addition, the ability of CoTSPc@MCM-41 to degrade other dyes, and the reuse studies, demonstrated that CoTSPc@MCM-41 could be reused for the degradation of most common dyes. © 2011 Elsevier B.V.

Wu D.,Zhejiang University | Jiang X.,Zhejiang University of Technology | Wu S.,Zhejiang University
Journal of Separation Science | Year: 2010

Tanshen, the rhizome of Salvia miltiorrhiza Bunge, is a famous Traditional Chinese Medicine for multiple therapeutic remedies. This work presents the isolation and puri-fication of tanshinone I and tanshinone IIA from the extract of the rhizome of S. miltiorrhiza by using high-speed counter-current chromatography (CCC) without presaturation of the two-phase solvent mixture. The CCC method combines the results of CCC solvent system selection and components analyses of solvent mixture by GC, and thus it is possible to add accurately each individual solvent to prepare single saturated solvent phase without presaturation. The optimum CCC solvent system is a system of hexane-ethyl acetate-ethanol-water (8:2:7:3, v/v), which has been determined by usual solvent system selection and CCC runs. As a result, over 98% pure tanshinone IIA and over 94% pure tanshinone I have been obtained by using less solvent volume. Their structures have been identified by ESI-MS, NMR spectra. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.

Wu Y.J.,Zhejiang University | Yu C.,Zhejiang University | Chen X.M.,Zhejiang University | Li J.,Zhejiang University of Technology
Journal of the American Ceramic Society | Year: 2012

Structure, dielectric response, and magnetic properties of Y 3Fe 5-xAl xO 12 (x = 0, 0.5, 1, 2, and 3) ceramics were investigated. X-ray diffraction (XRD) patterns indicate a single phase with garnet structure in space group Ia3d for all sintered samples. Rietveld refinement of XRD data suggest that Al 3+ substitutes for Fe 3+ at tetrahedral sites. All the samples show a giant dielectric response which originates from the charge carrier hopping between the Fe 2+ and Fe 3+. The activation energy of the hopping process increases with increasing Al substitution. The a-d super-exchange interaction becomes weak as the content of Al increases, which results in the decrease of saturation magnetizations and magnetic ordering temperatures. © 2012 The American Ceramic Society.

Liu Y.,Zhejiang University | Liu Y.,Zhejiang University of Technology | Wang H.,Zhejiang University | Yu J.,Yunnan University | Li P.,Zhejiang University
Journal of Process Control | Year: 2010

Online identification of nonlinear systems is still an important while difficult task in practice. A general and simple online identification method, namely Selective Recursive Kernel Learning (SRKL), is proposed for multi-input-multi-output (MIMO) systems with the nonlinear autoregressive with exogenous input form. A two-stage RKL online identification framework is first formulated, where the information contained by a sample (i.e., the new arriving or old useless one) can be introduced into and/or deleted from the model, recursively. Then, a sparsification strategy to restrict the model complexity is developed to guarantee all the output channels of the MIMO model accurate simultaneously. Specially, a novel pruning approach based on the fast leave-one-out cross-validation criterion is explored to acquire generalization ability by determining and then deleting the useless information. Consequently, the model can adaptively adjust its structure to capture the process dynamics. The SRKL method is applied intensively to several nonlinear systems for multifold identification aims. The obtained results show that SRKL is superior to traditional methods, e.g., artificial neural networks and fuzzy systems, in different situations. The benefits of its accuracy, reliable performance and simple implementation in practice indicate that SRKL is promising for online identification of nonlinear systems. © 2009 Elsevier Ltd. All rights reserved.

Tao W.,TRINA SOLAR LTD | Du Y.,Zhejiang University of Technology
Solar Energy | Year: 2015

In this work we investigate how the optical properties of monocrystalline silicon and polycrystalline silicon wafers are affected by texturing techniques and encapsulation. For monocrystalline wafers, the KOH etching is better than acid etching while reactive ion etching (RIE) is proven to be preferred compared to acid etching for polycrystalline wafers. The differences in reflectance (R) between two textures are apparent before encapsulation, but when the textured wafers are encapsulated with glass especially antireflectance coated (ARC) glass, the difference can be reduced from about five percentage points to below a percentage point. More important, the optical losses caused by reflectance (R) losses and parasitic absorption losses (A) for four types of commercial monocrystalline and polycrystalline silicon module are quantified and compared. Analyses are carried out for eight configurations using a stratified model consisting of solar cell wafers as well as cover glass and ethylene vinyl acetate (EVA). The model is to first obtain the external reflectance (R) and transmittance (T) in each layer, and the spectrally parasitic absorption loss associated with the cover glass and EVA is calculated with the aid of R and T measurements, which allows us to do a complete optical loss analysis for the solar module. The results show that the KOH texture with ARC glass encapsulation may be better choice for monocrystalline wafers, which gives a 94.04% of effective light collected by silicon. The RIE technique with ARC glass is suitable for polycrystalline substrates with excellent light trapping of 94.14%. After all, reflectance from glass surface and silicon surface accounts for over 70% of total loss, while the absorption of glass and EVA accounts for the rest and less loss. © 2015 Elsevier Ltd.

Zuo X.-J.,Zhejiang University of Technology | Zhou Y.,Nanjing University
New Journal of Physics | Year: 2015

Weidentify a novel type of periodic charge-density modulation in triangular-lattice materials near an incommensurate filling. These charge modulations are suppressed by a strong pairing interaction, leaving the pairing modulations with the same periodicity.Wealso explore the competition between charge-densitywaves and superconductivity in chirald + id or f-wave superconductors, andwe discuss the implications for cobaltate and organic superconductors. Furthermore, we self-consistently calculate the local density of states around impurities and show that the gap anisotropy of the chiral d + id state is doping-dependent,which naturally explains the close-to-nodal gap features of cobaltate superconductors as indicated by experiments. © 2015 IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

Huang G.,Taizhou University | Chen S.,Taizhou University | Tang S.,Taizhou University | Gao J.,Zhejiang University of Technology
Materials Chemistry and Physics | Year: 2012

An intumescent flame retardant, poly(piperazine spirocyclic pentaerythritol bisphosphonate) (PPSPB), has been covalently grafted onto the surfaces of graphene oxide (GO) to obtain GO-PPSPB and according nanocomposites were prepared via solvent blending. The X-ray diffraction (XRD) and transmission electron microscopy (TEM) results show that the chemically reduced GO-PPSPB (CRG-PPSPB) can achieve better dispersion in the ethylene vinyl acetate copolymer (EVA) matrix and exfoliated EVA/CRG-PPSPB nanocomposites are formed. The results from thermogravimetric analysis (TGA) and cone calorimeter tests indicate that CRG-PPSPB improve thermal stability and reduce obviously the flammability (including peak heat release rate (PHRR), total heat release (THR), average mass loss rate (AMLR), etc.) of EVA. Compared with pure EVA resin, the PHRR of the EVA/CRG-PPSPB nanocomposites filled with 1 wt% CRG-PPSPB is reduced by about 56%. The SEM images show that a compact, dense and uniform intumescent char is formed for EVA/CRG-PPSPB nanocomposites after combustion. The functionalization of graphene by intumescent flame retardant PPSPB can improve both the dispersion of graphene sheets in the polymer matrix and flame retardancy of the nanocomposites. © 2012 Elsevier B.V. All rights reserved.

Wang P.,Zhejiang University of Technology | Wang P.,Peking University | Yi W.,Anhui University of Science and Technology | Xianlong G.,Zhejiang Normal University
New Journal of Physics | Year: 2015

We study the quench dynamics of a one-dimensional ultracold Fermi gas with synthetic spin-orbit coupling. At equilibrium, the ground state of the system can undergo a topological phase transition and become a topological superfluid with Majorana edge states. As the interaction is quenched near the topological phase boundary, we identify an interesting dynamical phase transition of the quenched state in the long-time limit, characterized by an abrupt change of the pairing gap at a critical quenched interaction strength. We further demonstrate the topological nature of this dynamical phase transition from edge-state analysis of the quenched states. Our findings provide interesting clues for the understanding of topological phase transitions in dynamical processes, and can be useful for the dynamical detection of Majorana edge states in corresponding systems. © 2015 IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

Zhang Y.J.,Chinese University of Hong Kong | Qian L.,Zhejiang University of Technology | Huang J.,Chinese University of Hong Kong
Foundations and Trends in Networking | Year: 2012

Optimization has been widely used in recent design of communication and networking systems. One major hurdle in this endeavor lies in the nonconvexity of many optimization problems that arise from practical systems. To address this issue, we observe that most nonconvex problems encountered in communication and networking systems exhibit monotonicity or hiddenmonotonicity structures. A systematic use of the monotonicity properties would substantially alleviate the difficulty in obtaining the global optimal solutions of the problems. This monograph provides a succinct and accessible introduction to monotonic optimization, including the formulation skills and solution algorithms. Through several application examples, we will illustrate modeling techniques and algorithm details of monotonic optimization in various scenarios. With this promising technique, many previously difficult problems can now be solved with great efficiency. With this monograph, we wish to spur new research activities in broadening the scope of application of monotonic optimization in communication and networking systems. © 2013 Y. J. (Angela) Zhang, L. Qian and J. Huang.

Long X.,Zhejiang University | Zhang G.,Zhejiang University of Technology | Han L.,Sinopec | Meng Q.,Zhejiang University
Water Research | Year: 2013

Oily sludge dewatering is practically needed prior to sludge treatments. However, the conventional use of physical treatments with or without chemical conditionings presented poor feasibility in industrial applications due to either poor cost-efficiency or lacking environmental friendliness. In this paper, biosurfactant rhamnolipid was for the first time applied for dewatering of oily sludge. Rhamnolipid treatments under the concentration of 300-1000mg/L, pH of 5-7 and temperature of 10-60°C could directly separate 50-80% of water from the stable oily sludge. And both mono-rhamnolipid and di-rhamnolipid were identified to be of equivalent dewatering ability, which is closely related to their equivalent performance in breaking the emulsified oil droplets. Demulsification was found to be involved in settling water from oily sludge. Furthermore, the effectiveness of rhamnolipid was further demonstrated at pilot scale (1000L) treatment of oily sludge. After pilot treatment, the settled water with residual oil of 10mg/L and soluble COD of about 800mg/L could be directly effluxed into the biotreatment system while the concentrated oil sludge with a reduced volume by 60-80% can be pumped into coking tower, achieving completely harmless treatment. It seems that rhamnolipid as dewatering agent was of great prospects in the industrial dewatering of oily sludge. © 2013 Elsevier Ltd.

Hu B.,Zhejiang University of Technology | Ren J.,Nankai University | Wang Z.,Nankai University
Tetrahedron | Year: 2011

We presented a Lewis acid-catalyzed nucleophilic ring opening of methylenecyclopropane (MCP) 1,1-diesters with propargyl alcohols. Unlike the proximal-bond cleavage mode observed in cases of unactivated MCPs, the intrinsic characteristic of MCP 1,1-diesters gave a regiospecific distal-bond cleavage under attack of propargyl alcohols as nucleophiles. By combining a subsequent intramolecular Conia-ene reaction, 3,5-dimethylenetetrahydropyrans could be obtained in either a stepwise or a one-pot strategy. © 2010 Elsevier Ltd. All rights reserved.

Cui P.,Shandong University | Zhang H.,Shandong University | Wang H.,Zhejiang University of Technology | Feng J.-E.,Shandong University
IET Control Theory and Applications | Year: 2014

A globally optimal real-time distributed fusion algorithm is discussed for multi-channel observation systems. The performance of the fusion is equal to that of centralised Kalman filtering. Different from the existing one based on information filters, the algorithm uses the projection theorem in Hilbert space according to First-Come-First-Serve principle. Local estimates are instantly fused with arrival of local information at fusion centre. Meantime, a real-time strategy is presented to balance the performance and the speed of fusion. Therefore the algorithm is flexible and has the practical benefits. © The Institution of Engineering and Technology 2014.

Pan J.-W.,Zhejiang University | He L.-N.,Zhejiang University of Technology | Xiao F.,Zhejiang University | Shen J.,Zhejiang University | Zhan R.-Y.,Zhejiang University
Critical Care | Year: 2013

Introduction: Lower gelsolin levels have been associated with the severity and poor outcome of critical illness. Nevertheless, their link with clinical outcomes of aneurysmal subarachnoid hemorrhage is unknown. Therefore, we aimed to investigate the relationship between plasma gelsolin levels and clinical outcomes in patients with aneurysmal subarachnoid hemorrhage. Methods: A total of 262 consecutive patients and 150 healthy subjects were included. Plasma gelsolin levels were measured by enzyme-linked immunosorbent assay. Mortality and poor long-term outcome (Glasgow Outcome Scale score of 1-3) at 6 months were recorded. Results: Plasma gelsolin levels on admission were substantially lower in patients than in healthy controls (66.9 (26.4) mg/L vs. 126.4 (35.4) mg/L, P < 0.001), and negatively associated with World Federation of Neurological Surgeons score (r = -0.554, P < 0.001) and Fisher score (r = -0.538, P < 0.001), and identified as an independent predictor of poor functional outcome (odds ratio, 0.957; 95% confidence interval (CI), 0.933-0.983; P = 0.001) and death (odds ratio, 0.953; 95% CI, 0.917-0.990; P = 0.003) after 6 months. The areas under the ROC curve of gelsolin for functional outcome and mortality were similar to those of World Federation of Neurological Surgeons score and Fisher score (all P > 0.05). Gelsolin improved the predictive values of World Federation of Neurological Surgeons score and Fisher score for functional outcome (both P < 0.05), but not for mortality (both P > 0.05).Conclusions: Gelsolin levels are a useful, complementary tool to predict functional outcome and mortality 6 months after aneurysmal subarachnoid hemorrhage. © 2013 Pan et al.; licensee BioMed Central Ltd.

Feng Y.,Zhejiang University of Technology | Yagoubi M.,Ecole des Mines de Nantes
Automatica | Year: 2016

This paper presents a complete solution to the problem of comprehensive admissibility for descriptor systems with unstable and nonproper weights. In such non-standard circumstances, it is hard to render the closed-loop system admissible due to the uncontrollable and unobservable weights. The necessary and sufficient condition is given and a specifically structured output feedback controller is conducted in terms of the dynamics of the weighs. It is shown that determining suitable controllers for a given descriptor system with the presence of unstable and nonproper weights requires solving an admissibility problem for an augmented system explicitly constructed in this paper. A numerical example is included to illustrate the current result. © 2016 Elsevier Ltd. All rights reserved.

Lv G.,Zhejiang University of Technology
Proceedings - 2011 4th International Symposium on Computational Intelligence and Design, ISCID 2011 | Year: 2011

Convolutional Neural Networks are popularly used in OCR and document recognition. This paper applies stochastic diagonal Levenberg-Marquardt method into a convolutional network, which is presented by Simard. The relations between the sample class number, global learning rate and the network's convergence speed are discussed, Experiments on different train sets showed that class number is an essantial factor to the neural network's convergence. We have successfully expeanded Simard network into recognition of multi-font style little character set like Baidu CAPTCHA and got a recognition rate as 98.4% in single Baidu CAPTCHA character, and 93.5% as the overall rate. Experiments in this paper has confirmed that Convolutional Neural Network can be successfully used in recognition of multi-fontstyle little character set. © 2011 IEEE.

Gong X.,Zhejiang University of Technology
Physical Chemistry Chemical Physics | Year: 2013

The control of surface properties such as the morphology, roughness, stiffness, and wettability of polyelectrolyte multilayers was carried out using poly(diallyldimethylammonium chloride) (PDADMAC) and poly(4-styrenesulfonic acid-co-maleic acid, 1 : 1 SS : MA) sodium salt (PSSMA 1 : 1) as the building blocks via adjusting the assembly pH value. We found that the surface roughness of the multilayers increased with increasing assembly pH value, and that the morphology was quite different at various assembly pH values when PSSMA was assembled as the final layer. However, the surface roughness and morphology of the multilayers (PDADMAC as the final layer) showed no apparent change at various assembly pH values. Interestingly, the stiffness of the PSSMA/PDADMAC multilayers could be tuned. Nanoindentation measurements by SFM showed that the hardness of the multilayers was very different at various pH values when PSSMA was the outermost layer. Conversely, the hardness of the multilayers remained unchanged regardless of the pH when PDADMAC was the outermost layer. The water contact angle hysteresis (the difference between the advancing and receding contact angles) of the multilayers was largely affected by both surface roughness and surface hydrophilic groups which could also be tuned by assembly pH. © 2013 the Owner Societies.

Jiang N.,Zhejiang University of Technology | Shelley J.D.,University of Manchester | Smith R.,University of Manchester
Applied Thermal Engineering | Year: 2014

The retrofit of heat exchanger networks requires detailed models of the heat exchangers for the detailed assessment of network performance. Network retrofit options include heat transfer enhancement. There is thus a requirement for detailed models of heat exchanger performance, including heat transfer enhancement, suitable for inclusion in network retrofit optimization algorithms. Such models must be robust, computationally efficient and accurate enough to reflect the heat transfer and pressure drop performance of actual equipment. This paper presents a simple but reliable method to model the performance of shell-and-tube heat exchangers, including heat transfer enhancement with tube inserts. Two commonly used tube inserts, twisted tapes and coiled wires, are investigated for tube-side heat transfer augmentation. A new set of consistent performance correlations covering all flow regions for twisted-tape and wired-coil inserts is introduced. The models can be conveniently used for existing exchanger simulation, rating and assessment of heat transfer enhancement. They can also be used for sizing new exchangers to be introduced in a network. A case study illustrates the application of these performance models. © 2014 Elsevier Ltd. All rights reserved.

Jiang N.,Zhejiang University of Technology | Shelley J.D.,University of Manchester | Doyle S.,University of Manchester | Smith R.,University of Manchester
Applied Energy | Year: 2014

Finding cost effective retrofits for heat exchanger networks remains a challenge. Whilst it is often straightforward to find retrofit changes to an existing network that can improve energy performance, in practice such changes are most often uneconomic. This paper will present an approach to heat exchanger network retrofit around a fixed network structure. Network energy performance is improved through the selective use of heat transfer enhancement. A sensitivity analysis is used to find the most effective heat exchangers to enhance in order to improve the performance of the overall network. The sensitivity analysis used is an extension of a previous sensitivity analysis that was introduced to study network flexibility. The proposed method is applicable for heat exchanger networks involving streams with linear or non-linear physical properties. The enhancement of the most sensitive heat exchangers and avoiding new equipment, together with piping and civil engineering costs, allow much more cost-effective heat exchanger network retrofit. © 2014 Elsevier Ltd.

Pei Z.,Zhejiang University of Technology
Applied Soft Computing Journal | Year: 2015

Abstract The TOPSIS method, commonly known as the technique for order preference by similarity to ideal solutions, is one of the most popular approaches used in multi-attribute decision making (MADM). The fundamental procedure of the traditional TOPSIS method is rather straightforward, the ranking position of an alternative depends on its relative closeness to the positive ideal solution and the negative ideal solution, respectively. In order to encompass uncertain and ambiguous decision elements, an extension of the original TOPSIS method has been coined. With the help of fuzzy sets based TOPSIS, an overwhelming trend of fuzzy decision making applications has been witnessed. In the present work, however, it is found that the extended fuzzy TOPSIS method is unable to distinguish all the different alternatives under linguistic environment. Moreover, the undistinguishable alternatives are countless in quantity, and they have formed specific patterns with respect to the parameters of TOPSIS methods. To dampen this ranking ambiguity, we designed a set of supplemental methods to construct a revised TOPSIS approach with linguistic evaluations. Correspondingly, the sufficiency of the revised TOPSIS method to guarantee total orders has been proven. Furthermore, a numerical example concerning the production line improvement of a manufacturing company is demonstrated to validate the feasibility and supremacy of the proposed method. Finally, a series of further discussions are performed to shed some lights on the impacts caused by the changes of the alternative quantity, the attribute quantity, and the type of linguistic term. © 2015 Elsevier B.V.

Sun M.,Zhejiang University of Technology
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2013

In this paper, we propose in a continuous-time framework incremental adaptation strategies for parametric uncertain systems. The issue of the bounded estimation is posed by considering merely the case of unsaturated adaptation. The partially- or fully-saturated adaptation laws are characterized analytically, to illustrate the flexibility in choice of adaptation laws. The presented analysis shows the asymptotic convergence of the system undertaken. © 2013 Springer-Verlag.

Miao Y.,Zhejiang University of Technology | Feng J.,Zhejiang University | Pajarola R.,University of Zurich
Computers and Graphics (Pergamon) | Year: 2011

Visual saliency can effectively guide the viewer's visual attention to salient regions of a 3D shape. Incorporating the visual saliency measure of a polygonal mesh into the normal enhancement operation, a novel saliency guided shading scheme for shape depiction is developed in this paper. Due to the visual saliency measure of the 3D shape, our approach will adjust the illumination and shading to enhance the geometric salient features of the underlying model by dynamically perturbing the surface normals. The experimental results demonstrate that our non-photorealistic shading scheme can enhance the depiction of the underlying shape and the visual perception of its salient features for expressive rendering. Compared with previous normal enhancement techniques, our approach can effectively convey surface details to improve shape depiction without impairing the desired appearance. © 2011 ElsevierLtd. Allrightsreserved.

Shao Y.-H.,Zhejiang University of Technology | Deng N.-Y.,China Agricultural University
Neural Computing and Applications | Year: 2013

For classification problems, twin support vector machine (TWSVM) determines two nonparallel hyperplanes by solving two related SVM-type problems. TWSVM classifies binary patterns by the proximity of it to one of the two nonparallel hyperplanes. Thus, to calculate the distance of a pattern from the hyperplane, we need the unity norm of the normal vector of the hyperplane. But in the formulation of TWSVM, these equality constraints were not considered. In this paper, we consider unity norm constraints by using Euclidean norm and add a regularization term with the idea of maximizing some margin in TWSVM and propose a novel margin-based twin support vector machines with unity norm hyperplanes (UNH-MTSVM). We solved UNH-MTSVM by Newton's method, and the solution is updated by conjugate gradient method. The performance of both the linear and nonlinear UNH-MTSVM is verified experimentally on several bench mark and synthetic datasets. Experimental results show the effectiveness of our methods in both computation time and classification accuracy. © 2012 Springer-Verlag London Limited.

Wang Q.,Zhejiang University of Technology
Yi chuan = Hereditas / Zhongguo yi chuan xue hui bian ji | Year: 2011

Overexpression of pleiotropic drug resistance (PDR) efflux pumps of the ATP-binding cassette (ABC) transporter superfamily is the major cause of fungal multi-drug resistance and decreased efficacy of antifungal drugs. This review focused on recent progresses in understanding of the PDR efflux pumps of ABC transporter superfamily in Saccharomyces cerevisiae and the fungal pathogens Candida albicans, Cryptococcus neoformans, and Aspergillus fumigates. The mechanisms underlying efflux pump-mediated drug resistance and the regulatory networks involved were discussed. Investigation of the PDR efflux pumps of ABC transporter superfamily and their impact on drug resistance may lead to strategies to overcome fungal multi-drug resistance and improve drug efficacy.

Pei Z.,Zhejiang University of Technology | Zheng L.,Tsinghua University
Expert Systems with Applications | Year: 2012

In this paper we present a new approach to solve multi-attribute decision making problems in intuitionistic fuzzy environment. This approach is based on a new ranking method of intuitionistic fuzzy sets, in which the evaluated values (in the form of intervals) of the same alternative with different attributes are considered as one unified entity. According to people's intuition, the ranking method proposed in this paper is mainly grounded on a revised score function and a revised accuracy function of intuitionistic fuzzy sets. Different from the traditional methods, in this new approach, the degree of membership, the degree of nonmembership and the degree of hesitation are considered with various importance in reflecting the true image of the respective alternative. Furthermore, an optimization model is established to estimate the relative degree of importance of each quantity. Finally, two practical examples are provided to illustrate our approach. © 2011 Elsevier Ltd. All rights reserved.

Cheng S.,Zhejiang University of Technology
PETMEI'11 - Proceedings of the 1st International Workshop on Pervasive Eye Tracking and Mobile Eye-Based Interaction | Year: 2011

Eye-tracking is a valuable tool for mobile device usability research, but there are still many challenges about how to create good usability evaluation, such as the accurate enough eye-movement data from the small view angle on a real mobile device. This paper presents one research framework, which combines the remote eye-tracker and portable eye-tracker for both quantitive and qualitative evaluation. An example is reported in which a mobile device user interface is analyzed in on-screen simulation using a remote eye-tracker, and with the real device using a portable eye-tracker. We get the usability problem lists and design advices at the end. It illustrates the feasibility and effectiveness for the proposed research framework. © 2011 ACM.

Jin Y.,Zhejiang University of Technology | Jin Y.,Max Planck Institute for Mathematics in the Sciences | Jost J.,Max Planck Institute for Mathematics in the Sciences | Wang G.,Albert Ludwigs University of Freiburg
Journal of Mathematical Imaging and Vision | Year: 2012

In this paper, we present a nonlocal version of the OSV model by using the new results of Bartholdi-Schick-Smale-Smale. We compare this model with other nonlocal models, both theoretically and in computer experiments. © 2011 Springer Science+Business Media, LLC.

Chen D.,Taizhou University | Pan F.,Taizhou University | Gao J.,Zhejiang University of Technology | Yang J.,Taizhou University
Synlett | Year: 2013

A direct C(sp3)-H amination reaction of isochroman derivatives with arylamines was developed in the presence of iron(II) salt. A variety of isochroman derivatives and primary amines were selectively transformed into the corresponding oxidative coupling products in good to excellent yield under mild conditions. © Georg Thieme Verlag Stuttgart, New York.

Zheng P.,University of Shanghai for Science and Technology | Ding B.,Zhejiang University of Technology
International Journal of Geomechanics | Year: 2016

In cylindrical coordinates, a potential method is developed for three-dimensional (3D) wave propagation in a poroelastic medium. By using the proposed potential method, the wave propagation problems can be reduced to the determination of four scalar potentials governed by four scalar Helmholtz equations, representing the motions of P1, P2, SV, SH waves in the porous media, respectively. By the methods of separation of variables, the general solutions to those Helmholtz equations are found in cylindrical coordinates. Boundary value problems associated with a homogeneous poroelastic half-space loaded by surface tractions, that is, Lamb's problem for a fluid-saturated medium is resolved using the obtained general solutions. It is shown that these potentials introduced in this research for 3D wave propagation problems can also be reduced to those reported by previous researchers for axisymmetric wave propagation in the fluid-saturated porous medium. Furthermore, numerical examples for the state-state and transient responses of the poroelastic half-space are provided. © 2015 American Society of Civil Engineers.

Su E.Y.,Zhejiang University of Technology
Zhongguo Zhong xi yi jie he za zhi Zhongguo Zhongxiyi jiehe zazhi = Chinese journal of integrated traditional and Western medicine / Zhongguo Zhong xi yi jie he xue hui, Zhongguo Zhong yi yan jiu yuan zhu ban | Year: 2012

To explore treatment methods for patients with severe aplastic anemia (SAA) failing in immunosuppressive therapy (IST). Totally 62 SAA patients failing in IST were treated by integrative medicine (IM). The treatment course was divided into three stages: the critical emergency stage, the improvement stage, and the recovery stage. In the critical emergency stage, patients were treated with Lingyang Yigui Decoction (LYD, consisting of 1.2 g antelope horn, 6 g coptis chinensis, 12 g stir-baked Fructus Gardeniae, 30 g rehmannia rhizoma, 50 g lalang grass rhizome, 9 g amur corktree bark, 12 g Cortex Moutan, 9 g ass-hide gelatin, 30 g red date, 6 g prepared licorice root, etc.) and Erzhi Busui Decoction (EBD, consisting of 120 g glossy privet fruit, 100 g eclipta prostrata, 24 g prepared Gold Theragran, 12 g fructus lycii, 90 g rehmannia rhizoma, 60 g astragalus, 9 g Angelica sinensis, 9 g ass-hide gelatin, 30 g honeysuckle flower, 12 g lotus plumule, and so on) alternatively, one dose daily, decocted twice, taken in two portions. Meanwhile, 50 mg Testosterone Propionate was intramuscularly injected every other day to the improvement stage. Those with fever were treated with LYD by adding 60 g gypsum, 60 g common anemarrhena, 30 g dandelion, 30 g bittersweet herb, 30 g blackend swallowwort root and rhizome, 15 g hemsley rockvine root tuber, and so on. In the improvement stage patients were treated with Jixueteng Compound (Jixueteng Zhengyang Decoction was administered to those of Shen-yang deficiency syndrome: consisting of 100 g spatholobus suberectus, 60 g astragalus, 3 g red ginseng, 12 g psoralea corylifolia, 18 g dodder seed, 12 g angelica, 18 g Herba Epimedii, 6 g common fenugreek seed, 24 g Gold Theragran, 30 g glossy privet fruit, 30 g eclipta prostrata, 6 g dried human placenta, and so on). Meanwhile, 50 mg Testosterone Propionate was intramuscularly injected every other day. Jixueteng Yijing Decoction was administered to those of Shen-yin deficiency syndrome: consisting of 100 g glossy privet fruit, 100 g eclipta prostrata, 90 g rehmannia rhizoma, 30 g spatholobus suberectus, 12 g dodder seed, 6 g psoralea corylifolia, 30 g prepared Gold Theragran, 9 g ass-hide gelatin, 9 g fructus lycii, 24 g Salvia miltiorrhiza, 30 g astragalus, 6 g angelica, and so on), one dose daily, decocted twice, taken in two portions. The treatment lasted to the recovery stage. The medication was gradually reduced to the follow-ups of drug discontinuance. Results After 6 -57 months of treatment, 12 patients (accounting for 19.4%) were basically cured, 14 (22.6%) relieved, 8 (12. 9%) markedly improved, 28 (45.2%) ineffectively, with the total effective rate of 54. 8%. Totally 23 patients had the body temperature ranging 37.6-38.5 degrees C at the first visit to our hospital. They took 2 h- 6 days to have pyretolysis ( <37.5 degrees C) after treatment. Twenty patients with body temperature higher than 38.5 degrees C took 4 h - 5 days to have pyretolysis after treatment. Totally 26 patients suffering from IST induced abnormalities of liver and renal functions (ALT, AST, BUN, and Cr) at the first visit were treated by IM for 2 months. They were restored to the normal levels in 25 cases. The treatment of SAA failing in IST had its specificity. The staging targeted treatment is in line with its pathophysiology. The key points for its treatment might be lie in the improvement and protection of hematopoietic microenvironment of bone marrows. The antisepsis and anti-inflammation of Chinese herbs hindered its aggravating tendency.

Gong X.,Zhejiang University of Technology
RSC Advances | Year: 2014

In general, techniques of particle arrays on polyelectrolyte multilayers involve complex and inefficient steps. Here, we present a simple yet robust method for fabricating ordered two-dimensional nanoparticle arrays on polyelectrolyte multilayers via water induced flow of multilayer films. The process is easy and repeatable without the requirement of complicated surface preparation or chemical modification. By droplet evaporation of silica or other functional nanoparticle solutions on a patterned PDMS stamp, nanoparticle arrays on polyelectrolyte multilayer film surfaces will occur when the PDMS stamp contacts with polyelectrolyte multilayers. This work provides a facile and efficient approach to fabricate colloidal nanoparticle or other functional nanoparticle arrays on polyelectrolyte multilayers which are potentially useful for sensor materials, biomaterials and so on. This journal is © the Partner Organisations 2014.

Sun M.,Zhejiang University of Technology
Proceedings - International Conference on Electrical and Control Engineering, ICECE 2010 | Year: 2010

In this paper, the problem of chaotic secure communication is addressed from an iterative learning perspective, where the plaintext spans over a pre-specified finite-time interval. In the cryptographic scheme, the plaintext is modulated through chaotic parameter modulation, and then chaotically masked by a nonlinear mechanism. An efficient learning algorithm is exploited for decryption, and the sufficient convergence condition is derived by which the learning gain can be chosen. Furthermore, two fundamental techniques are given in order to enhance security. Case studies are carried out to demonstrate the effectiveness of the proposed method. © 2010 IEEE.

Lou J.,Ningbo University | He L.,Ningbo University | Du J.,Ningbo University | Wu H.,Zhejiang University of Technology
Composite Structures | Year: 2016

In this paper, a general nonlinear four-variable refined plate model is developed to investigate the bending and free vibration behavior of a functionally graded (FG) microplate resting on an elastic foundation. In this model, a shape function is defined to describe the effect of the transverse shear deformation, and the size effects of the microplate are captured by using the modified couple stress theory. Firstly, the equations of motion and boundary conditions are derived from the Hamilton's principle. Then the equations of motion are reduced to ordinary differential equations by applying the Galerkin method, and via solving the ordinary differential equations, closed-form solutions for the nonlinear bending deflection and vibration frequency are obtained. It is found that the solutions for the general refined plate model are identical to those for a size-dependent Kirchhoff plate model and a refined first-order plate model respectively when the shape function of the transverse shear deformation is chosen to be certain forms. In addition, numerical studies are carried out to compare a special nonlinear size-dependent refined higher-order plate model with its linear counterpart as well as the nonlinear refined first-order plate model. © 2016 Elsevier Ltd.

Zhonghui Z.,Zhejiang Police College | Xiaowei Z.,Zhejiang University of Technology | Fang F.,Zhejiang GongShang University
Saudi Journal of Biological Sciences | Year: 2014

The present study was designed to determine the effects of Ganoderma lucidum polysaccharides (GL-PS) on exhaustive exercise-induced oxidative stress in skeletal muscle tissues of mice. The mice were divided into four groups (three GL-PS administered groups and the control group). The control group was administered with distilled water and GL-PS administered groups were administered with GL-PS (50, 100 and 200. mg/kg body weight per day). After 28. days, the mice performed an exhaustive swimming exercise, along with the determination of superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT) activities and malondialdehyde (MDA) levels in the skeletal muscle of mice. The results showed that GL-PS could increase antioxidant enzymes activities and decrease the MDA levels in the skeletal muscle of mice. This study provides strong evidence that GL-PS supplementation possessed protective effects against exhaustive exercise-induced oxidative stress. © 2013.

Xuan Q.,Zhejiang University of Technology | Du F.,Zhejiang University | Li Y.,Zhejiang University City College | Wu T.-J.,Zhejiang University
IEEE Transactions on Automation Science and Engineering | Year: 2011

Topological structure is considered more and more important in managing a supply network or predicting its development. In this paper, a new framework is proposed to model the topological structure of supply networks, where different types of supply networks can be created just by introducing different supplier-customer connecting rules. Generally, the networks created in the framework are much different from the random networks with the same degree sequences. The revealed phenomenon suggests that real-world supply networks may benefit from its intrinsic mechanism on flexibility, efficiency, and robustness to target attacks. © 2010 IEEE.

Cong R.-G.,North China Electrical Power University | Cong R.-G.,Lund University | Shen S.,Zhejiang University of Technology
The Scientific World Journal | Year: 2014

To address the problems of climate change and energy security, Chinese government strived to develop renewable power as an important alternative of conventional electricity. In this paper, the learning curve model is employed to describe the decreasing unit investment cost due to accumulated installed capacity; the technology diffusion model is used to analyze the potential of renewable power. Combined with the investment cost, the technology potential, and scenario analysis of China social development in the future, we develop the Renewable Power Optimization Model (RPOM) to analyze the optimal development paths of three sources of renewable power from 2009 to 2020 in a cost-effective way. Results show that (1) the optimal accumulated installed capacities of wind power, solar power, and biomass power will reach 169000, 20000, and 30000 MW in 2020; (2) the developments of renewable power show the intermittent feature; (3) the unit investment costs of wind power, solar power, and biomass power will be 4500, 11500, and 5700 Yuan/KW in 2020; (4) the discounting effect dominates the learning curve effect for solar and biomass powers; (5) the rise of on-grid ratio of renewable power will first promote the development of wind power and then solar power and biomass power. © 2014 Rong-Gang Cong and Shaochuan Shen.

Wu Z.-M.,Dalian University of Technology | Hu C.-H.,Dalian University of Technology | Wu Y.-F.,City University of Hong Kong | Zheng J.-J.,Zhejiang University of Technology
Construction and Building Materials | Year: 2011

External bonding of fiber reinforced polymer (FRP) is one of the most efficient techniques for retrofitting and strengthening concrete structures. However, the bond interface is the weakest link in such retrofitted or strengthened concrete members, resulting in premature FRP debonding. Therefore, a newly improved hybrid bonded FRP (IHB-FRP) technique is developed in this paper for strengthening concrete members. Unlike the conventional mechanical fastening method, the mechanical fasteners in the technique do not penetrate the FRP strips and the capping plates serve to apply vertical pressure to the FRP strips. An experimental study on the flexural strength of IHB-FRP technique strengthened beams is conducted. It is found that all the beams strengthened with the IHB-FRP technique fail due to tensile rupture of FRP strips even for seven plies of FRP strips. Based on the experimental results, the effects of the steel reinforcement ratio, the number of FRP plies, and the fastener spacing on the ultimate load are evaluated. Finally, a simplified method is proposed for estimating the ultimate bending moment of the IHB-FRP strengthened beam. The validity of the method is verified with the experimental results. © 2011 Elsevier Ltd. All rights reserved.

Liu H.-S.,Zhejiang University of Technology | Lu H.,Beijing Normal University
Journal of High Energy Physics | Year: 2013

We obtain the charged rotating black hole in conformal gravity. The metric is asymptotic to the (anti-)de Sitter spacetime. The contribution to the metric from the charges has a slower falloff than that in the Kerr-Newman AdS black hole. We analyse the global structure and obtain all the thermodynamical quantities including the mass, angular momentum, electric/magnetic charges and their thermodynamical conjugates. We verify that the first law of thermodynamics holds. We also obtain the new neutral rotating black holes that are beyond Einstein metrics. In contrast to the static ones, these rotating black holes have no parameters associated with the massive spin-2 hair. © 2013 SISSA.

Li B.,Zhejiang University of Technology
Modern Physics Letters B | Year: 2012

A new method is proposed to improve the response time of organic photodetectors by using displacement current. By inserting a transparent organic dielectric layer between the organic semiconductor active layer and the electrode the displacement current will be produced and replace the conduction current for current propagation, which will overcome the disadvantage of low carrier mobility of organic semiconductors. Under the irradiation of nanosecond pulse laser the rise time and fall time of the organic photodetector based on displacement current decrease 10% and 86%, respectively comparing to the conventional organic photodetector based on conduction current, which indicates the displacement current could renew the operation principle for high-speed organic photodetectors. © 2012 World Scientific Publishing Company.

Gao J.,Zhejiang University of Technology | Wang J.,McGill University
Computers and Operations Research | Year: 2010

This study presents a novel weight-based multiobjective artificial immune system (WBMOAIS) based on opt-aiNET, the artificial immune system algorithm for multi-modal optimization. The proposed algorithm follows the elementary structure of opt-aiNET, but has the following distinct characteristics: (1) a randomly weighted sum of multiple objectives is used as a fitness function. The fitness assignment has a much lower computational complexity than that based on Pareto ranking, (2) the individuals of the population are chosen from the memory, which is a set of elite solutions, and a local search procedure is utilized to facilitate the exploitation of the search space, and (3) in addition to the clonal suppression algorithm similar to that used in opt-aiNET, a new truncation algorithm with similar individuals (TASI) is presented in order to eliminate similar individuals in memory and obtain a well-distributed spread of non-dominated solutions. The proposed algorithm, WBMOAIS, is compared with the vector immune algorithm (VIS) and the elitist non-dominated sorting genetic system (NSGA-II) that are representative of the state-of-the-art in multiobjective optimization metaheuristics. Simulation results on seven standard problems (ZDT6, SCH2, DEB, KUR, POL, FON, and VNT) show WBMOAIS outperforms VIS and NSGA-II and can become a valid alternative to standard algorithms for solving multiobjective optimization problems. © 2009 Elsevier Ltd. All rights reserved.

Li F.,Hangzhou Normal University | Zhang X.,Zhejiang University of Technology | Zhang H.,Hangzhou Normal University | Jiang K.,Hangzhou Normal University
Journal of Mass Spectrometry | Year: 2013

In this study, the gas phase chemistry of the protonated benzyl esters of proline has been investigated by electrospray ionization mass spectrometry and theoretical calculation. Upon collisional activation, the protonated molecules undergo fragmentation reactions via three primary channels: (1) direct decomposition to the benzyl cation (m/z 91), (2) formation of an ion-neutral complex of [benzyl cation + proline]+, followed by a hydride transfer to generate the protonated 4,5-dihydro-3H-pyrrole-2-carboxylic acid (m/z 114), and (3) electrophilic attack at the amino by the transferring benzyl cation, and the subsequent migration of the activated amino proton leading to the simultaneous loss of (H2O + CO). Interestingly, no hydrogen/deuterium exchange for the fragment ion m/z 114 occurs in the d-labeling experiments, indicating that the transferring hydride in path-b comes from the methenyl hydrogen rather than the amino hydrogen. For para-substituted benzyl esters, the presence of electron-donating substituents significantly promotes the direct decomposition (path-a), whereas the presence of electron-withdrawing ones distinctively inhibits that channel. For the competing channels of path-b and path-c, the presence of electron-donating substituents favors path-b rather than path-c, whereas the presence of electron-withdrawing ones favors path-c rather than path-b. Copyright © 2013 John Wiley & Sons, Ltd. Copyright © 2013 John Wiley & Sons, Ltd.

Li X.-F.,Central South University | Yu Z.-W.,Central South University | Zhang H.,Zhejiang University of Technology
Journal of Constructional Steel Research | Year: 2011

Free vibration of shear beams is studied when rotational motion is taken into account, while classical shear beams do not consider rotational motion. From a single governing equation of Timoshenko beams, we analytically derive Rayleigh beams and shear beams as two limiting cases of the ratio of reduced shear stiffness to bending stiffness being sufficiently large and small, respectively. Emphasis is placed on the analysis of free vibration of nonclassical shear beams without damping effect. Under the condition of general end restraints, a characteristic equation for nonclassical shear beams with finite rotational inertia is derived in explicit form. A condition that the nonclassical shear beams reduce to the classical ones is found, and classical shear beams may be understood as nonclassical ones with infinite large rotational inertia. Nonclassical natural frequencies and mode shapes are calculated for a standing shear beam on an elastic foundation. Previous results of pinned-free, and free-free shear beams can be taken as special cases of the present analysis. The effects of finite rotational inertia, material properties, geometrical conditions and end restraints on the natural frequencies of shear beams are discussed. © 2011 Elsevier Ltd. All rights reserved.

Combining the first-principles noncollinear calculations of scattering matrices with Andreev approximation, we investigated the spin-triplet Andreev reflection (AR) spectra for the interface between half-metallic ferromagnet Co 2MnSi and s-wave BCS superconductor Al with and without interfacial roughness, where the orientations of magnetic moments near the interface are randomly distributed. The calculated results show that the AR spectra have peak structures near zero bias for the clean interface with relative weak magnetic disorder. With the increasing degree of interfacial roughness or magnetic disorder, these subgap peaks of conductance spectra will be washed out. The results also show that the value of subgap conductance spectrum can be raised significantly by the magnetic disorder. Finally, our calculations reveal that the long-range spin-triplet AR in Co 2MnSi/Al(001) interface can be enhanced by a small amount of interfacial roughness. © 2012 World Scientific Publishing Company.

Du L.-H.,Zhejiang University of Technology | Luo X.-P.,Zhejiang Agriculture And forestry University
Synthetic Communications | Year: 2010

A green, efficient method for the synthesis of various 2-aryl- benzimidazoles in the presence of hypervalent iodine as the oxidant at room temperature under solvent-free conditions is reported. The salient features of this method include mild conditions, short reaction times (3-5min), excellent yields, and simple procedure. © 2010 Taylor & Francis Group, LLC.

Xu Y.,University of Wuppertal | Xu Y.,Zhejiang University of Technology | Yuan H.,University of Wuppertal
Engineering Fracture Mechanics | Year: 2011

In conventional cohesive zone models the traction-separation law starts from zero load, so that the model cannot be applied to predict mixed-mode cracking. In the present work the cohesive zone model with a threshold is introduced and applied for simulating different mixed-mode cracks in combining with the extended finite element method. Computational results of cracked specimens show that the crack initiation and propagation under mixed-mode loading conditions can be characterized by the cohesive zone model for normal stress failure. The contribution of the shear stress is negligible. The maximum principal stress predicts crack direction accurately. Computations based on XFEM agree with known experiments very well. The shear stress becomes, however, important for uncracked specimens to catch the correct crack initiation angle. To study mixed-mode cracks one has to introduce a threshold into the cohesive law and to implement the new cohesive zone based on the fracture criterion. In monotonic loading cases it can be easily realized in the extended finite element formulation. For cyclic loading cases convergence of the inelastic computations can be critical. © 2010 Elsevier Ltd.

Shen C.,Zhejiang University | Meng Q.,Zhejiang University | Zhang G.,Zhejiang University of Technology
Journal of Membrane Science | Year: 2011

Both hemocompatibility and cytocompatibility of biomaterials are the prerequisite for the application in tissue engineering. Although polyethylene glycol (PEG) has attracted considerable attention for its good hemocompatibility in resisting adsorption of platelets and proteins, so far no report has focused on how to prevent the adsorption of small molecules which is also key characterization of hemocompatibility. Further, PEG is bioinert and usually elicits no cell-surface interactions, which is also the obstacle for application in tissue engineering. In this regard, this paper aimed to improve both hemocompatibility and cytocompatibility of polysulfone (PSU) membrane by grafting PEG. The novel PEG grafted PSU (PSU-g-PEG) membrane fabricated in the experiments held dramatically higher water flux and bovine serum albumin (BSA) permeability than PSU membrane. It also showed low adsorption to small molecular drugs with either hydrophilicity or hydrophobicity, while the PSU membrane adsorbed hydrophobic drugs severely. Moreover, the cytocompatibility of the PSU-g-PEG membrane can be achieved by the regulation of hepatocyte self-assembly. Unlike the nonsurviving cells on PSU membrane, hepatocytes on PSU-g-PEG membrane could self-assemble into small spheroids which maintained cell viability and liver-specific functions within 96. h of culture. The specific hemocompatibility and cytocompatibility of PSU-g-PEG membrane suggest strong potential applicability in tissue engineering as well as in drug investigation in vitro. © 2011 Elsevier B.V.

Li P.,Zhejiang University of Technology | Qu W.,Tongji University
Advanced Materials Research | Year: 2012

Biodeposition treatment had been proposed as alternative techniques for improvement in the durability of concrete structures. Laboratory experiments were conducted by bacterially mediated carbonate precipitation on the surface and subsurface of specimens of concrete. Some properties of specimens and crystal, such as the crystal phase, morphology and growth of the crystal deposited on specimens, water penetration, the resistance towards carbonation of concrete and so on, were analyzed by XRD, SEM, water absorptivity test and concrete accelerated carbonation test. Some efficiencies of biodeposition treatment for were investigated by experiment. Results show that the mineral crystal deposits uniformly on the surface and subsurface of specimens, phases of crystal are calcite and vaterite. Biodeposition effectively reduces capillary water uptake and leading to carbonation rate constant decreased by 25~40%. Bacterially mediated carbonate mineralization can be an ecological and novel alternative for improvement in the durability of concrete structures.

Lu X.-M.,China Institute of Technology | Lu P.-Z.,Zhejiang University of Technology
Applied Microbiology and Biotechnology | Year: 2014

The 454 pyrosequencing technique was applied to evaluate microbial community composition in sediment and water samples collected from the river receiving effluents from a swine farm and a farmhouse restaurant, respectively. For each sample, 4,600 effective sequences were selected and used to do the bacterial diversity and abundance analysis, respectively. Bacterial phylotype richness in the river sediment sample without effluent input was higher than the other samples, and the river water sample with addition of effluent from the swine farm had the least richness. Effluents from both the swine farm and the farmhouse restaurant have the potential to decrease the bacterial diversity and abundance in the river sediment and water, especially it is more significant in the river sediment. Effect of effluent from the swine farm on riverine bacterial communities was more significant than that from the farmhouse restaurant. Characterization of bacterial community composition in sediments from two tributaries of the downstream river showed that various effluents from the swine farm and the farmhouse restaurant have the similar potential to reduce the natural variability in riverine ecosystems, and contribute to the biotic homogenization in the river sediment. © 2014 Springer-Verlag.

Li W.,Zhejiang University | Liu N.,Zhejiang University | Cai L.-L.,Zhejiang University | Jiang J.-L.,Zhejiang University | Chen J.-M.,Zhejiang University of Technology
Bioresource Technology | Year: 2011

Biological reduction of Fe(III) to Fe(II) is a key step in nitrogen oxide (NOx) removal by the integrated chemical absorption-biological reduction process. NOx removal efficiency strongly depends on the concentration of Fe(II) in the scrubbing liquid. In this study, a newly isolated strain, Enterococcus sp. FR-3, was used to reduce Fe(III) chelated with citrate to Fe(II). Strain FR-3 reduced citrate-chelated Fe(III) with an efficiency of up to 86.9% and an average reduction rate of 0.21mMh-1. SO4 2- was not inhibitory whereas NO2 - and SO3 2- inhibited cell growth and thus affected Fe(III) reduction. Models based on the Logistic equation were used to describe the relationship between growth and Fe(III) reduction. These findings provide some useful data for Fe(III) reduction, scrubber solution regeneration and NOx removal process design. © 2010 Elsevier Ltd.

Chen S.,Zhejiang University of Technology | Li X.,Beijing Normal University
Computational and Mathematical Methods in Medicine | Year: 2012

Functional magnetic resonance imaging (fMRI) is recently developed and applied to measure the hemodynamic response related to neural activity. The fMRI can not only noninvasively record brain signals without risks of ionising radiation inherent in other scanning methods, such as CT or PET scans, but also record signal from all regions of the brain, unlike EEG/MEG which are biased towards the cortical surface. This paper introduces the fundamental principles and summarizes the research progress of the last year for imaging neural activity in the human brain. Aims of functional analysis of neural activity from fMRI include biological findings, functional connectivity, vision and hearing research, emotional research, neurosurgical planning, pain management, and many others. Besides formulations and basic processing methods, models and strategies of processing technology are introduced, including general linear model, nonlinear model, generative model, spatial pattern analysis, statistical analysis, correlation analysis, and multimodal combination. This paper provides readers the most recent representative contributions in the area. Copyright © 2012 Shengyong Chen and Xiaoli Li.

Chen L.,Zhejiang University of Technology
Journal of Dispersion Science and Technology | Year: 2011

Water-based architectural heat insulation coating was studied to overcome the drawbacks of conventional inorganic silicate heat insulation coating. The heat insulation coatings were prepared with the method of mechanical agitation when the technology of emulsion blending was adopted, and the mixed organic polymer emulsions were used as binder of the coatings and the mixed heat insulating aggregates were applied as powder, and nanoscaled SiO2 and TiO2 were introduced, and some assistants were also added. Results showed that the prepared coating had excellent physical-chemical properties. The test of the authoritative inspection organization shows that coefficient of heat conductivity is 0.073 W/mK, which is lower by far than that of conventional heat-insulating materials. The time of artificial weathering is more than 1000 hours. Water temperature difference in the plastic container, which was coated with heat insulation coatings, represented the heat-insulating property of the coatings. The influences of components of mixed polymer emulsion, mass ratio of polymer emulsion to powder, component of heat insulating aggregates, particle size of heat insulating aggregates, nanoscaled SiO2 and TiO2 on the properties of the coatings were studied. © Taylor & Francis Group, LLC.

Wan J.-P.,Jiangxi Normal University | Lin Y.,Jiangxi Normal University | Cao X.,Zhejiang University of Technology | Liu Y.,Jiangxi Normal University | Wei L.,Jiangxi Normal University
Chemical Communications | Year: 2016

An unprecedented C=C bond cleavage of enaminones has been realized by means of copper catalysis in the presence of hypervalent iodine (PhI(OAc)2). The cascade transformation based on this bond cleavage leads to the synthesis of various α-keto amides. Isotope labeling experiments suggest that water has acted as a source of oxygen atoms during the generation of the new carbonyl group. © The Royal Society of Chemistry 2016.

Fu Z.-J.,Zhejiang University of Technology
Chinese Control Conference, CCC | Year: 2015

In this paper, an adaptive on-line identification algorithm is proposed for nonlinear structure uncertain perturbation systems via discrete different time scales dynamic neural networks. The main contributions of this paper are: (1) it is the first time to develop an identifier for nonlinear structure uncertain perturbation systems by using different time scales dynamic neural networks in discreet time domain (2)the input-to-state stability (ISS) approach is used to tune the weights of the discrete different time scales dynamic neural networks in the sense of L∞. The commonly used robustifying techniques, such as dead-zone or σ-modification in the weight tuning, are not necessary for the proposed identification algorithm. The stability of the proposed identifier is proved by Lyapunov function and ISS theory. Simulation results are given to demonstrate the correctness of the theoretical results. © 2015 Technical Committee on Control Theory, Chinese Association of Automation.

Xu J.,Zhejiang University | Lv X.,Zhejiang University | Li J.,Zhejiang University of Technology | Li Y.,Zhejiang University | And 3 more authors.
Journal of Hazardous Materials | Year: 2012

Nanoscale Pd/Fe particles were combined with multi-walled carbon nanotubes (MWNTs) to prepare supported particles (MWNT-stabilized Pd/Fe), which were used to remove 2,4-dichlorophenol (2,4-DCP). The adsorption capacity of MWNTs was found to be increased with the increasing amount of chlorine atoms, and the removal rates of phenol (P), 2-chlorophenol (2-CP), 4-chlorophenol (4-CP) and 2,4-DCP reached 19.7%, 60.5%, 72.0% and 95.1% respectively, in 1min by MWNTs due to π-π interaction. The adsorption kinetics and adsorption isotherm were also discussed. MWNTs as a supporter, was effective for avoiding the agglomeration of nZVI. Furthermore, the speedy removal efficiency of the initial substances (2,4-DCP) reached about 50% in 1min, and over the time continued to rise to 100%, remaining low concentrations (<1mgL -1) of the intermediate substances (o-CP, p-CP), and gradual release of the final substance (P) from MWNT-stabilized Pd/Fe composites during the whole process, proposed a novel method for in situ remediation technology. © 2012 Elsevier B.V.

Huan R.,Zhejiang University of Technology | Pan Y.,Zhejiang University
IET Radar, Sonar and Navigation | Year: 2011

In this study, three decision fusion strategies in synthetic aperture radar (SAR) image target recognition for classification of ground vehicles in the Moving and Stationary Target Acquisition and Recognition public release database are proposed. These strategies include multi-view decision fusion strategy, multi-feature decision fusion strategy and multi-classifier decision fusion strategy. In multi-view decision fusion strategy, each view implements its recognition process individually and provides only its decision from the classifier to the fuser. In multi-feature decision fusion strategy, a variety of feature extraction algorithms are used to extract features from an image separately and each of the extracted feature vectors is submitted to a classifier. The decisions from the classifiers are then provided to the fuser. In multi-classifier decision fusion strategy, different classifiers are used to classify a feature vector. Each classifier executes its classification process individually and then provides its decision to the fuser. The fuser combines decisions to produce a single fused final decision in these three strategies. The three proposed strategies are evaluated and verified with experiments. Experimental results indicate that there are significant target recognition performance benefits in the probability of correct classification, when the proposed decision fusion strategies are properly applied in SAR image target recognition. © 2011 The Institution of Engineering and Technology.

Zheng J.-J.,Zhejiang University of Technology | Dai J.-G.,Hong Kong Polytechnic University
Construction and Building Materials | Year: 2014

This paper attempts to predict the nonlinear pull-out response of fiber reinforced polymer (FRP) rods embedded in steel tubes filled with cement grout. Based on a tri-linear bond-slip model, the whole FRP rod is divided into three zones: linear elastic, softening, and frictional. In each zone, a set of two second-order ordinary differential equations are established in terms of the displacements of the FRP rod and steel tube and solved in an analytical manner. When the thickness of the steel tube approaches infinity, the solution can be applied to the problem of FRP rods embedded in rock. Based on the derived solution, the interfacial bond properties and snapback phenomenon are discussed. After the analytical solution is validated by comparisons with four sets of experimental data, the effects of the radius and length of FRP rods, the local peak bond stress and the residual frictional strength on the maximum pull-out load are evaluated through sensitivity analysis. © 2014 Elsevier Ltd. All rights reserved.

Zhang F.,Zhejiang University of Technology | Zhang F.,University of Cambridge | Spring D.R.,University of Cambridge
Chemical Society Reviews | Year: 2014

The use of coordinating moieties as directing groups for the functionalisation of aromatic carbon-hydrogen (C-H) bonds has become an efficient strategy for the selective construction of new carbon-carbon (C-C) and carbon-heteroatom (C-X) bonds in arenes. However many directing groups cannot be easily removed/modified from the products after C-H functionalisation, thus limiting the structural diversity of the products. This limitation can be overcome by employing removable/modifiable or traceless directing groups which can be easily attached to the starting materials and detached from the products. In this tutorial review, we give an overview of recent advances in this emerging field which have dramatically increased the synthetic applicability of C-H functionalisation processes. This journal is © the Partner Organisations 2014.

Wu Z.,Dalian University of Technology | Rong H.,Dalian University of Technology | Zheng J.,Zhejiang University of Technology | Xu F.,Dalian University of Technology | Dong W.,Dalian University of Technology
Engineering Fracture Mechanics | Year: 2011

This paper presents an experimental investigation on the properties of the fracture process zone (FPZ) in concrete using the digital image correlation (DIC) technique. Based on the experimental results, it is found that the FPZ length increases during crack propagation but decreases after the FPZ is fully developed. The FPZ length at the peak load and the maximum FPZ length increase with an increase in specimen height, but decrease by increasing the notch depth to specimen height ratio. It is also found that the crack extension length at the peak load is about 0.25 times the ligament length. © 2011 Elsevier Ltd.

Luo S.-P.,Leibniz Institute for Catalysis at the University of Rostock | Luo S.-P.,Zhejiang University of Technology | Esteban Mejia,Leibniz Institute for Catalysis at the University of Rostock | Friedrich A.,University of Rostock | And 10 more authors.
Angewandte Chemie - International Edition | Year: 2013

Of noble descent: A fully noble-metal-free system for the photocatalytic reduction of water at room temperature has been developed. This system consists of CuI complexes as photosensitizers and [Fe3(CO) 12] as the water-reduction catalyst. The novel Cu-based photosensitizers are relatively inexpensive, readily available from commercial sources, and stable to ambient conditions, thus making them an attractive alternative to the widely used noble-metal based systems. © 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mi L.-Q.,Zhejiang University of Technology
Astrophysics and Space Science | Year: 2013

Quantum entropy of extremal black holes has been discussed by many authors. However the contribution of inner event horizon has not been considered. In this paper, we consider the Reissner-Nordström-anti-de Sitter black hole, and show that the contributions lead extremal black hole entropy to obey the Nernst theorem, naturally. Therefore the contributions are important and cannot be neglected in near-extremal and extremal black hole cases. © 2012 Springer Science+Business Media Dordrecht.

Chen L.J.,Zhejiang University of Technology
Chinese Chemical Letters | Year: 2011

Novel self cross-linking fluorinated acrylic latex (SCLFAL) has been successfully prepared via starved seeded semi-batch emulsion polymerization. The resultant SCLFAL is characterized by Fourier transform infrared (FTIR) spectrometry. Contact angle (CA) and glass transition temperature (T g) of the film are investigated. Results show that CA and T g of the film can be improved when the moderate amount of HPMA is introduced into the mixed monomers. © 2011 Li Jun Chen.

Wang H.,Zhejiang University of Technology | Zhang H.,Shandong University
Automatica | Year: 2013

This paper considers the linear quadratic (LQ) control problem for the Itô-type stochastic system with input delays. Due to simultaneous appearances of diffusion terms (dependent on the state and the control) as well as delays in the dynamic system, the problem is very involved and remains to be solved. We not only provide the solvable condition of the problem but also the explicit expression of the causal and adapted controller for a kind of LQ problems. All of these are based on a stochastic Riccati equation. The key technique is to pursue the explicit cost value of the LQ problem by FBSDE and derive the analytical controller via the interplay between the original problem and its equivalent abstract description. © 2013 Elsevier Ltd. All rights reserved.

Sun M.-X.,Zhejiang University of Technology
International Journal of Automation and Computing | Year: 2015

Typical masking techniques adopted in the conventional secure communication schemes are the additive masking and modulation by multiplication. In order to enhance security, this paper presents a nonlinear masking methodology, applicable to the conventional schemes. In the proposed cryptographic scheme, the plaintext spans over a pre-specified finite-time interval, which is modulated through parameter modulation, and masked chaotically by a nonlinear mechanism. An efficient iterative learning algorithm is exploited for decryption, and the sufficient condition for convergence is derived, by which the learning gain can be chosen. Case studies are conducted to demonstrate the effectiveness of the proposed masking method. © 2015, Institute of Automation, Chinese Academy of Sciences and Springer-Verlag Berlin Heidelberg.

Feng Y.,Zhejiang University of Technology
Journal of the Franklin Institute | Year: 2015

This paper presents a less conservative and numerically tractable solution to the static state feedback positive real control problem for affinely parameter dependent discrete-time singular systems. Relied on the use of auxiliary matrices and a positive scalar decision variable, a novel necessary and sufficient condition of positive realness is first derived in terms of a strict matrix inequality for linear time-invariant discrete-time singular systems. This characterization leads to a numerically efficient and reliable way for the controller design synthesis. Then, the results are further expanded to parameter dependent singular systems whose coefficient matrices are affine functions of a time-invariant uncertain parameter vector. Both robust analysis and robust controller synthesis are addressed. Numerical examples are included to illustrate the effectiveness of the present results. © 2014 The Franklin Institute.

Huang G.,Taizhou University | Zhuo A.,Zhejiang University of Science and Technology | Wang L.,East China University of Science and Technology | Wang X.,Zhejiang University of Technology
Materials Chemistry and Physics | Year: 2011

A phosphorus-nitrogen containing compound, N-(2-(5,5-dimethyl-1,3,2- dioxaphosphinyl-2-ylamino)-N-hexylformamide-2-propenyl acid (DPHPA), was synthesized and characterized. A novel flame retardant, namely DPHPA modified layered double hydroxides (DPHPA-LDHs), was prepared by ion-exchange of LDHs with DPHPA. The results from FT-IR, XPS, XRD and TEM showed that DPHPA intercalated LDHs and PMMA-DPHPA-LDHs nanocomposites had been prepared by in situ polymerization of PMMA with flame retardant DPHPA-LDHs. The storage modulus (E′) and glass transition temperature (Tg) of the nanocomposites were enhanced by incorporating DPHPA-LDHs into the PMMA. The results of flammability showed that the addition of flame retardant DPHPA-LDHs enhanced the flame retardancy of PMMA significantly. Compared to pure PMMA, the PHRR of the nanocomposites filled with 5 wt% DPHPA-LDHs is reduced by about 35%. The results of SEM and TEM showed that a compact and dense intumescent char is formed for PMMA-DPHPA-LDHs nanocomposites after combustion. The functionalization of LDHs by intumescent flame retardant DPHPA can improve both the dispersion of LDHs in the polymer matrix and flame retardancy of the nanocomposites. © 2011 Elsevier B.V. All rights reserved.

Yao F.,Jiangxi Normal University | Yao F.,Zhejiang University of Technology | Hao W.,Jiangxi Normal University | Cai M.-Z.,Jiangxi Normal University
Journal of Organometallic Chemistry | Year: 2013

A copper(I)-catalyzed tandem reaction of 2-iodophenols with isothiocyanates in hydrophobic [bmim][PF6] ionic liquid was described, which proceeded smoothly and generated a variety of 2-iminobenzo-1,3-oxathioles in good to excellent yields. The tandem reaction that was carried out in [bmim][PF6] has some obvious advantages such as reaction rate acceleration and yield increasing as compared with the reaction run in volatile solvents such as toluene. Furthermore, the CuI/1,10-phenanthroline catalytic system can be reused up to 6 times without loss of activity and efficiency. © 2012 Elsevier B.V. All rights reserved.

Zhu J.,Zhejiang University of Technology | Chen W.,Zhejiang University | Yang J.,University of Nebraska - Lincoln
Ultrasonics | Year: 2014

We study the propagation of thickness-twist (TT) waves in a crystal plate of AT-cut quartz with periodically varying, piecewise constant thickness. The scalar differential equation by Tiersten and Smythe is employed. The problem is found to be mathematically equivalent to the motion of an electron in a periodic potential field governed by Schrodinger's equation. An analytical solution is obtained. Numerical results show that the eigenvalue (frequency) spectrum of the waves has a band structure with allowed and forbidden bands. Therefore, for TT waves, plates with periodically varying thickness can be considered as phononic crystals. The effects of various parameters on the frequency spectrum are examined. © 2014 Elsevier B.V. All rights reserved.

Deng D.,Zhejiang University of Technology | Yang Y.,Zhejiang University | Gong Y.,Zhejiang University | Li Y.,Zhejiang University | And 2 more authors.
Green Chemistry | Year: 2013

Palladium nanoparticles supported on a mesoporous graphitic carbon nitride, Pd@mpg-C3N4, has been developed as an effective, heterogeneous catalyst for the liquid-phase semihydrogenation of phenylacetylene under mild conditions (303 K, atmospheric H2). A total conversion was achieved with high selectivity of styrene (higher than 94%) within 85 minutes. Moreover, the spent catalyst can be easily recovered by filtration and then reused nine times without apparent lose of selectivity. The generality of Pd@mpg-C3N4 catalyst for partial hydrogenation of alkynes was also checked for terminal and internal alkynes with similar performance. The Pd@mpg-C3N4 catalyst was proven to be of industrial interest. © 2013 The Royal Society of Chemistry.

Wang W.,Zhejiang University of Technology
Metallurgical and Mining Industry | Year: 2015

The tourism industry is a comprehensive industry, the status of industry in the national has become increasingly important, and closely linked with other industries, the adjustment of economic structure and optimization play a key role, in order to study the contribution of the tourism industry to the national economy scientifically and reasonably, this paper based on AHP (Analytic Hierarchy Process) analysis the role of tourism income completely in GDP, tourism foreign exchange earnings increased role of foreign investment, the role of tourism in poverty alleviation and development of other factors, Elaborate the tourism industry in economic growth, the consumer society, employment tripartite social contribution of the national economy in the face. © 2015. Metallurgical and Mining Industry.

Zhang Q.,Zhejiang University of Technology
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2016

A classical-kind phase-space formalism is developed to address the tiny intrinsic dynamical deviation from what is predicted by Wilczek-Zee theorem during quantum adiabatic evolution on degeneracy levels. In this formalism, the Hilbert space and the aggregate of degenerate eigenstates become the classical-kind phase space and a high-dimensional subspace in the phase space, respectively. Compared with the previous analogous study by a different method, the current result is qualitatively different in that the first-order deviation derived here is always perpendicular to the degeneracy subspace. A tripod-scheme Hamiltonian with two degenerate dark states is employed to illustrate the adiabatic deviation with degeneracy levels. © 2016 American Physical Society.

Zhang Q.,Zhejiang University of Technology | Gong J.,National University of Singapore
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2016

Superconducting systems such as those modeled by the Kitaev Hamiltonian are found to exhibit Zitterbewegung (ZB) oscillations. Remarkably, the dispersion relation in one-dimensional Kitaev systems allows for wave packets of arbitrary size to undergo nondecaying ZB oscillations without any distortion, with the typical ZB amplitude being one lattice site. To motivate possible experimental interest in this dynamical aspect of superconducting systems, we further show that a certain on-resonance modulation of the Hamiltonian parameter can be exploited to convert ZB oscillations to net drifting of the particle's and hole's wave packet along opposite directions, leading to long-distance particle-hole separation. © 2016 American Physical Society.

Zhao J.,Beijing Jiaotong University | Zheng J.-J.,Zhejiang University of Technology | Peng G.-F.,Beijing Jiaotong University | Van Breugel K.,Technical University of Delft
Cement and Concrete Research | Year: 2014

High-performance concrete (HPC) is prone to spalling under fire conditions. However, few quantitative theoretical studies on the spalling mechanism are available in the literature and the spalling mechanism has not been well interpreted. In this paper, the spalling behavior of cubic specimens is numerically modeled and the spalling mechanism is investigated at a meso-level. In modeling, the temperature field, the thermal decomposition of cement paste, the build-up vapor pressure, the moisture transport, and the distribution and evolution of thermal stresses in concrete are analyzed in a quantitative manner. Based on the numerical results, the spalling mechanism is interpreted from different angles. It is concluded that the explosive spalling of HPC specimens under fire exposure is mainly attributed to the temperature gradient-induced thermal stress. © 2014 Elsevier Ltd.

Chi K.,Zhejiang University of Technology | Jiang X.,Tohoku University | Horiguchi S.,Tohoku University
Computer Networks | Year: 2010

Reliable multicast, the lossless dissemination of data from one sender to a group of receivers, has a wide range of important applications. Recently, network coding has been applied to the reliable multicast in wireless networks, where multiple lost packets with distinct intended receivers are XOR-ed together as one packet and forwarded via single retransmission, resulting in a significant reduction of bandwidth consumption. However, the simple XOR operation cannot fully exploit the potential coding opportunities and finding the optimal set of lost packets for XOR-ing is a complex NP-complete optimization problem. In this work, we intend to move beyond the simple XOR to more general coding operations. Specifically, we propose two new schemes (a static scheme which repeatedly retransmits one coding packet until all intended receivers receive it and a dynamic scheme which updates the coding packet once one or more receivers receive it) to encode packets with more general coding operations, which not only can encode lost packets with common intended receivers together to fully exploit the potential coding opportunities but also have polynomial-time complexity. We demonstrate, through both analytical and simulation results, that the proposed schemes can more greatly reduce the bandwidth requirement than the available coding-based schemes, especially in the case of high packet loss probabilities and a larger number of receivers. This reduction can vary from a few percents to over 15% depending on the packet loss probabilities and the number of receivers. © 2010 Elsevier B.V. All rights reserved.

Li J.,Zhejiang University of Technology
Optik | Year: 2013

Based on the theory of high order moments of laser beams, the beam propagation factor of a high-power laser diode is analyzed. Analytical expressions are derived for components of the beam factor along the fast (M x) and slow (My) axis of the junction plane, respectively. It is shown that components of the beam factor Mx and My along orthogonal directions of junction planes of a diode laser may behave in different manners. On one hand, Mx is verified to be four and independent of parameters with regard to waveguide structures. On the other hand, My varies and depends on the ratio of the waveguide parameters. Besides, influences of each structural parameter on behaviors of My and the total one M are also discussed, respectively. © 2012 Elsevier GmbH.

Shen C.,Zhejiang University | Zhang G.,Zhejiang University of Technology | Meng Q.,Zhejiang University
PLoS ONE | Year: 2012

Cytocompatibility is critically important in design of biomaterials for application in tissue engineering. However, the currently well-accepted "cytocompatible" biomaterials are those which promote cells to sustain good attachment/spreading. The cells on such materials usually lack the self-assembled cell morphology and high cell functions as in vivo. In our view, biomaterials that can promote the ability of cells to self-assemble and demonstrate cell-specific functions would be cytocompatible. This paper examined the interaction of polyethylene glycol (PEG) modified polysulfone (PSf) membranes with four epithelial cell types (primary liver cells, a liver tumor cell line, and two renal tubular cell lines). Our results show that PSf membranes modified with proper PEG promoted the aggregation of both liver and renal cells, but the liver cells more easily formed aggregates than the renal tubular cells. The culture on PEG-modified PSf membranes also enhanced cell-specific functions. In particular, the cells cultured on F127 membranes with the proper PEG content mimicked the in vivo ultrastructure of liver cells or renal tubules cells and displayed the highest cell functions. Gene expression data for adhesion proteins suggest that the PEG modification impaired cell-membrane interactions and increased cell-cell interactions, thus facilitating cell self-assembly. In conclusion, PEG-modified membrane could be a cytocompatible material which regulates the morphology and functions of epithelial cells in mimicking cell performance in vivo. © 2012 Shen et al.