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Progress in Natural Science:Materials International 2006年第1期16卷 16-20页

作者： ZHANG Lingxin1, LIN Jianzhong1and ZHANG Weifeng 2.1.Department of Mechanics, state key {2. of Fluid Power Transmission and Control, zhejiang university, hangzhou 31.027, china 2. Institute of Marine and Coastal Sciences, Rutgers university, New Brunswick, New Jersey, USA) Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China Institute of Marine and Coastal Sciences Rutgers University New Brunswick NJ United States

The equation for the orientation probability function of slender cylindrical particles suspended in planar turbulent flows was investigated. After ensemble averaging, the equations for the mean and fluctuating probability function were derived. The equation for the fluctuating probability function appearing in the equation of mean probability function was solved by using the method of characteristics analysis. The orientational dispersion terms due to the random motion of cylindrical particles in the equation of mean probability function are related to the mean probability function and the Lagrangian fluid velocity correlations. The evolution of the mean probability function was described by a modified oriental ion-space-convection equation, where the dispersion terms account for the randomizing effect of the turbulence.

关键词： dispersion cylindrical particle suspensions turbulent flow probability function.

Catalytic Performance and Texture of TEOS Based Cu/SiO_2.Catalysts for Hydrogenation of Dimethyl Oxalate to Ethylene Glycol

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Chemical Research in Chinese Universities 2012年第1期28卷 119-123页

作者： WANG Shu-rong, YIN Qian-qian and LI Xin-bao state key {2. of Clean Energy Utilization, zhejiang university, hangzhou 31.027, P. R. china zhejiang university State Key Laboratory of Clean Energy Utilization Hangzhou 310027

Highly active and selective Cu/SiO2.catalysts for hydrogenation of dimethyl oxalate（DMO） to ethylene glycol（EG） were successfully prepared by means of a convenient one-pot synthetic method with tetraethoxysi lane（TEOS） as the source of silica. XRD, H2.TPR, SEM, TEM, XRF and N2.physisorption measurements were performed to characterize the texture and structure of Cu/SiO2.catalysts with different copper loadings. The active components were highly dispersed on SiO2.supports. Furthermore, the coexistence of Cu0 and Cu＋ contributed a lot to the excellent performance of Cu-TEOS catalysts. The DMO conversion reached 100% and the EG selectivity reached 95% at 498 K and 2.MPa with a high liquid hourly space velocity over the 2.-Cu-TEOS catalyst with an actual cop per loading of 19.0%（mass fraction）.

关键词： Cu/SiO2 TEOS Hydrogenation Dimethyl oxalate Ethylene glycol

SIMULATION OF FLUID FLOW IN CHANNEL OF A NOVEL HYDRAULIC SHOCK GENERATOR

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Chinese Journal of Mechanical Engineering 2000年第4期13卷 258-262页

作者： Fu XinYang Huayong (state key {2. of Fluid Power Transmission and Control, zhejiang university) 浙江大学流体传动及控制国家重点实验室浙江杭州

In order to improve the engineering performance of a novel hydraulic shock generator, the fluid flow inside its complex passages is numerically investigated. The effects of the inlet flow velocity upon the turbulence intensity of the jet flow are analyzed. The calculated pressure loss is experimentally verified with the consideration of temperature determined viscosity shifting. The results are used as the reference in the further development of the hydraulic shock generator

关键词： Shock generator Numerical simulation Jet flow Turbulence

Comparing Genetic Characteristics of Retrotransposon TOS17 During Different Tissue Culture Processes in the Rice Cultivars Nipponbare and Shishoubaimao

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Agricultural Sciences in china 2010年第2期9卷 157-162页

作者： LI Kuan, WANG Chuang, YING Shan and SHOU Hui-xia state key {2. of Plant Physiology and Biochemistry, College of Life Sciences, zhejiang university, hangzhou 310058, P.R.china state key {2. of Plant Physiology and Biochemistry College of Life Sciences Zhejiang University Hangzhou 310058 P.R. China

As a retrotransposon, TOS17 was a useful tool for rice genetic and functional genomic research. To ascertain the feasibility of constructing a TOS17 insertion mutation library in the rice cultivar Shishoubaimao, the genetic and expression characteristics of TOS17 were analyzed. We made solid and suspension tissue cultures and confirmed the copy numbers of TOS17 at different time points in both tissue culture processes by real-time quantitative PCR （RT-qPCR）. Three primary copies of TOS17 were detected in naturally grown Shishoubaimao. TOS17 was activated by tissue culture, and the copy numbers of TOSI7 increased along with a prolonged tissue culture time in both the Nipponbare and the Shishoubaimao cultivars. Therefore, Shishoubaimao is a potential candidate for constructing a TOS17 insertion mutant library. Compared with Nipponbare, TOS17 was more active in Shishoubaimao during tissue culture. Higher copy numbers of TOS17 were obtained with the suspension tissue culture process than with the solid tissue culture process over the same time courses. We concluded that 3-4 months of suspension tissue culture time is suitable for constructing a TOS17 insertion mutant library in Shishoubaimao.

关键词： Shishoubaimao tissue culture TOS17 copy number insertion mutant library

Two-dimensional thermoelasticity solution for functionally graded thick beams

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 451-460页

作者： Lü Chaofeng1, CHEN Weiqiu1 & ZHONG Zheng2.1. Department of Civil Engineering, zhejiang university, hangzhou 31.027,{2. 2. key laboratory of Solid Mechanics of Ministry of Education, School of Aerospace Engineering and Ap- plied Mechanics, Tongji university, Shanghai 2.0092.{2. Department of Civil Engineering Zhejiang University Hangzhou China key laboratory of Solid Mechanics of Ministry of Education School of Aerospace Engineering and Applied Mechanics Tongji University Shanghai China

Two-dimensional thermoelasticity analysis of functionally graded thick beams is presented using the state space method coupled with the technique of differential quadrature. Material properties vary continuously and smoothly through the beam thickness, leading to variable coefficients in the state equation derived from the elasticity equations. Approximate laminate model is employed to translate the state equation into the one with constant coefficients in each layer. To avoid numerical instability, joint coupling matrices are introduced according to the continuity conditions at interfaces in the approximate model. The differential quadrature procedure is applied to discretizing the beam in the axial direction to make easy the treatment of arbitrary end conditions. A simply-supported beam with exponentially varying material properties is considered to validate the present method. Numerical examples are performed to investigate the influences of relative parameters.

关键词： state equation differential quadrature approximate laminate model joint coupling matrices thermal stresses.

Physically-based approach to analyze rainfall-triggered landslide using hydraulic gradient as slide direction

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Journal of zhejiang university-Science A(Applied Physics & Engineering) 2012年第12期13卷 943-957页

作者： Qi-hua RAN1,Dan-yang SU1,Qun QIAN1,Xu-dong FU2.Guang-qian WANG1,2.Zhi-guo HE3 (1Department of Hydraulic Engineering,zhejiang university,{2. 310058,china) (2.4} key laboratory of Hydroscience and Engineering,Tsinghua university,Beijing 100084,china) (3Department of Ocean Science and Engineering,zhejiang university,{2. 310058,china) Department of Hydraulic Engineering Zhejiang University Hangzhou China state key {2. of Hydroscience and Engineering Tsinghua University Beijing China Department of Ocean Science and Engineering Zhejiang University Hangzhou China

An infinite slope stability numerical model driven by the comprehensive physically-based integrated hydrology model(InHM) is *** this approach,the failure plane is assumed to be parallel to the hydraulic gradient instead of the slope *** method helps with irregularities in complex terrain since depressions and flat areas are allowed in the *** present model has been tested for two synthetic single slopes and a small catchment in the Mettman Ridge study area in Oregon,United states,to estimate the shallow landslide *** results show that the present approach can reduce the simulation error of hydrological factors caused by the rolling topography and depressions,and is capable of estimating spatial-temporal variations for landslide susceptibilities at simple slopes as well as at catchment scale,providing a valuable tool for the prediction of shallow landslides.

关键词： Shallow landslide Infinite slope stability model Hydraulic gradient Physically-based hydrology model Integrated hydrology model(InHM)

Advances in cell sources of hepatocytes for bioartificial liver

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Hepatobiliary & Pancreatic Diseases International 2012年第6期11卷 594-605页

作者： Xiao-Ping Pan , Lan-Juan Li state key {2. for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, zhejiang university School of Medicine, hangzhou 310003, china state key {2. for Diagnosis and Treatment of Infectious Diseases First Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003 China

BACKGROUND: Orthotopic liver transplantation (OLT) is the most effective therapy for liver failure. However, OLT is severely limited by the shortage of liver donors. Bioartificial liver (BAL) shows great potential as an alternative therapy for liver failure In recent years, progress has been made in BAL regarding genetically engineered cell lines, immortalized human hepatocytes, methods for preserving the phenotype of primary human hepatocytes, and other functional hepatocytes derived from stem cells. DATA SOURCES: A systematic search of PubMed and ISI Web of Science was performed to identify relevant studies in English language literature using the key words such as liver failure bioartificial liver, hepatocyte, stem cells, differentiation, and immortalization. More than 2.0 articles related to the cell sources of hepatocyte in BAL were systematically reviewed. RESULTS: Methods for preserving the phenotype of primary human hepatocytes have been successfully developed. Many genetically engineered cell lines and immortalized human hepatocytes have also been established. Among these cell lines the incorporation of BAL with GS-HepG2.cells or alginate encapsulated HepG2.cells could prolong the survival time and improve pathophysiological parameters in an animal model of liver failure. The cBAL111 cells were evaluated using the AMC-BAL bioreactor, which could eliminate ammonia and lidocaine, and produce albumin. Importantly, BAL loading with HepLi-4 cells could significantly improve the blood biochemical parameters, and prolong the survival time in pigs with liver failure. Other functional hepatocytes differentiated from stem cells, such as human liver progenitor cells, have been successfully achieved. CONCLUSIONS: Aside from genetically modified liver cell lines and immortalized human hepatocytes, other functionalhepatocytes derived from stem cells show great potential as cell sources for BAL. BAL with safe and effective liver cells may be achieved for clinical liver fa

关键词： bioartificial liver liver failure hepatocyte liver cell source stem cell differentiation immortalization

Virtual Reality Based Process Integrated Simulation Platform in Refinery:Virtual Refinery and Its Application

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china Petroleum Processing & Petrochemical Technology 2011年第3期13卷 74-84页

作者： Zhou Zewei Feng Yiping Rong Gang Wu Yucheng (state key {2. of Industrial Control Technology,Institute of Cyber-Systems and Control,zhejiang university,hangzhou 31.027,china) state key {2. of Industrial Control Technology Institute of Cyber-Systems and Control Zhejiang University Hangzhou 310027 China

With the combination between system simulation and virtual reality,we have established an integrated virtual refinery simulation platform,and analyzed the overall design and principal *** paper introduces a simulation algorithm about a refinery based on virtual reality,and explains how the algorithm can be applied to the virtual refinery integrated simulation platform in *** virtual refinery simulation platform,which consists of a three-dimensional scene system,an integrated database system and a dynamic-static simulation system,has many applications,such as dynamic-static simulation of key process unit used as process control and oil tank blending simulation for *** the visualization and human-computer interaction for acquiring production and process data,this platform can provide effective supports on staff training related with monitoring,control and operation in *** refinery can also be web published through the internet and it is helpful for the distance training and education.

关键词： virtual refinery petrochemical enterprise process integrated simulation information representation intelligent manufacturing systems

Geometric meanings of the parameters on rational conic segments

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Science china Mathematics 2005年第9期 59-72页

作者： HU Qianqian & WANG Guojin Department of Mathematics,zhejiang university,{2. 31.027,china state key laboratory of cad&cg,zhejiang university,{2. 31.027,china

Using algebraic and geometric methods,functional relationships between a point on a conic segment and its corresponding parameter are derived when the conic segment is presented by a rational quadratic or cubic Bézier *** is,the inverse mappings of the mappings represented by the expressions of rational conic segments are *** formulae relate some triangular areas or some angles,determined by the selected point on the curve and the control points of the curve,as well as by the weights of the rational Bézier ***,the relationship can be expressed by the corresponding parametric angles of the selected point and two endpoints on the conic segment,as well as by the weights of the rational Bézier *** results are greatly useful for optimal parametrization,reparametrization,etc.,of rational Bézier curves and surfaces.

关键词： rational Bézier curve conic segment ellipse hyperbola parabola parameterization.

Research on the mechanics of underwater supersonic gas jets

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中国科学：物理学、力学、天文学英文版 2010年第3期53卷 527-535页

作者： SHI HongHui1, WANG BoYi2.& DAI ZhenQing2.1 College of Mechanical Engineering and Automation, zhejiang Sci-Tech university, {2. 310018, china 2.state key laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, china College of Mechanical Engineering and Automation Zhejiang Sci-Tech University Hangzhou China state key {2. of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing China

An experimental research was carried out to study the fluid mechanics of underwater supersonic gas jets. High pressure air was injected into a water tank through converging-diverging nozzles (Laval nozzles). The jets were operated at different conditions of over-, full- and under-expansions. The jet sequences were visualized using a CCD camera. It was found that the injection of supersonic air jets into water is always accompanied by strong flow oscillation, which is related to the phenomenon of shock waves feedback in the gas phase. The shock wave feedback is different from the acoustic feedback when a supersonic gas jet discharges into open air, which causes screech tone. It is a process that the shock waves enclosed in the gas pocket induce a periodic pressure with large amplitude variation in the gas jet. Consequently, the periodic pressure causes the jet oscillation including the large amplitude expansion. Detailed pressure measurements were also conducted to verify the shock wave feedback phenomenon. Three kinds of measuring methods were used, i.e., pressure probe submerged in water, pressure measurements from the side and front walls of the nozzle devices respectively. The results measured by these methods are in a good agreement. They show that every oscillation of the jets causes a sudden increase of pressure and the average frequency of the shock wave feedback is about 5–10 Hz.

关键词： underwater supersonic gas jet pressure oscillation flow visualization shock wave feedback