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Journal of Hydrodynamics 1991年第1期3卷 37-44页

作者： Zhang Hui-sheng, department of Applied mechanics, Fudan university, shanghai 200433, P. R. china Fudan Univ Shanghai China

This paper improves the discrete vortex method for modeling Kelvin-Helmholtz instability and Rayleigh-Tay- lor instability by proper choice of velocity weighted average coefficients, redistribution of markers and successive adding of computational points with the increase of interfacial deformation and gives the numerical results of Rayleigh-Taylor instability. The numerical results show that the first two techniques greatly enhance the ability of the discrete vortex method for modeling large interracial deformations and the last technique greatly reduces the computational amounts of the numerical modeling at large deformation stage. The numerical modeling of Rayleigh- Taylor instability not only reproduces some phenomena such as the roll up at the end part of the spike observed in experiments but also finds some new phenomena such as the splashes at the roll up parts which needs to be tested by experiment.

关键词： mode NUMERICAL MODELING OF KELVIN-HELMHOLTZ INSTABILITY AND RAYLEIGH-TAYLOR INSTABILITY AT LARGE DEFORMATION STAGE NUMERICAL METHOD AND NUMERICAL RESULTS OF RAYLEIGHTAYLOR INSTABILITY AT

Impact chaos control and stress release——A key for development of ultra fine vibration milling

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Progress in Natural Science:Materials International 2002年第5期12卷 18-23页

作者： WANG Shulin(department of Power Engineering, university of shanghai for Science and Technology, shanghai 200093, china) shanghai Univ Sci & Technol Dept Power Engn Shanghai 200093 Peoples R China

Through our previous experimental and analytical studies, it has been discovered that the key for the development of vibration milling is the impact chaos control and stress release. The necessities for the chaos control and stress release are: (i) to strictly e-liminate the sub-harmonics; (ii) to control the super-harmonics to a lower level and (iii) to load the system compressively with relatively higher period, in order that the vibration energy can be absorbed by the particles effectively and sufficiently. A new vibration model for ultra fine milling is proposed, which has wide applications in preparing ultra fine particles.

关键词： vibration mills ultra fine milling impact chaos control stress release.

One of the origins for curved edges of polyethylene singlecrystals

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Chinese Science Bulletin 1998年第7期43卷 564-568页

作者： YAN Deyue department of Applied Chemistry, shanghai Jiaotong university, shanghai 200030, china department of Applied Chemistry Shanghai Jiaotong University Shanghai China

A new concept of lattice strain was developed to explain the origin of the curved edges of polyethylene (PE) single crystals. In the crystallization of PE from poor solvents, the length of critical nucleus generated is rather short. The thin lamellae are thermodynamically unstable especially at high temperature. Thereby, during the growth of PE single crystals an annealing process is going on simultaneously, which results in a reduction of thickness from the center to growing faces of lamellae. It is known that the thinner the single crystals, the bigger the unit-cell dimensions. Consequently, unit-cells in the central part of single crystals formed are somewhat smaller than those in the outer part of the same crystals. In order to fit in with the gradual enlargement of unit-cell dimensions from the center to the edges of single crystals, the lattice planes of a faster growing dominant {110} deform to be a set of parallel arcs of concentric circles. Accordingly, the edge of a slower growing subordinate {200} becomes a part of an ellipse with obvious curvature while the edge of a {110} sector remains almost straight for it is a small part of a large circumference.

关键词： PE single crystals curved lateral habit lattice strain.

The　θ－Methods　in　Numerical　Solution　of　Systems　of　Differential　Equations　with　Two　Delay　Terms

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Journal of Systems Engineering and Electronics 1994年第3期5卷 32-40页

作者： Tian Hongjiong & Kuang Jiaoxun (department of Mathematics, shanghai Normal university, shanghai 200234, china) department of Mathematics Shanghai Normal University Shanghai 200234 China

This paper deals with the numerical solution of initial value problems for systems of differential equations with two delay terms. We investigate the stability of adaptations of the θ-methods in the numerical solution of test equations u'(t) = a 11 u(t) + a12v(t) + b11 u(t - τ1) + b12v(t-τ2,v'(t) = a21 u(t) + a22 v(t) + b21 u(t -τ1,) + b22 v(t -τ2), t>0,with initial conditionsu(t)=u0(t),v(t) =v0(t), t≤*** aij, bij∈C, τj >0, i,j = 1,2,, and u0(t), v0(t)are continuous and complex valued. Sufficient conditions for the asymptotic stability of test equation are derived. Furthermore, with respect to an appropriate definition of stability for the numerical method, it is proved that the linear θ-method is stable if and only if 1/2≤θ≤1 and the one-leg θ-method is stable if and only if θ= 1.

关键词： Delay differential equations Numerical solution θ-methods Asymptotic stability Schur polynomial.

Approximate Analytical Solution of Blasius'Equation

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Communications in Nonlinear Science and Numerical Simulation 1998年第4期3卷 260-263页

作者： Jihuan HE(shanghai university, shanghai Institute of Applied Mathematics and mechanics,shanghai 200072, china)Email: glliu@*** shanghai university Shanghai Institute of Applied Mathematics and Mechanics Shanghai 200072 China

The Blasius’ equation f"’ + ff"/2=0, with boundary conditions f(0) =f,(0)0, f’ (+∞)=1 is studied in this paper. An approximate analytical solution is obtained via the variational iteration method. The comparison w... 详细信息

关键词： nonlinear technique variational iteration method Blasius’ flow variational technique

Delayed feedback control experiments on some flexible structures

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Acta Mechanica Sinica 2010年第6期26卷 951-965页

作者： Guo-Ping Cai·Long-Xiang Chen department of Engineering mechanics, State Key Laboratory of Ocean Engineering, shanghai Jiaotong university,200240 shanghai,china department of Engineering mechanics State Key Laboratory of Ocean Engineering Shanghai Jiaotong University Shanghai China

In recent decades,studies on delayed system dynamics have attracted increasing attention and advances have been achieved in stability,nonlinearity,delay identification, delay elimination and ***,most of the existing work is on the theoretical basis and little is on the *** paper presents our experimental studies on delayed feedback control conducted in recent years with the focus on the discussion of a DSP-based delayed experiment *** phenomena in our delay experiments are discussed and a few topics of interest for further research are brought forward.

关键词： Flexible beam Flexible plate Flexible manipulator Delayed feedback control Experiment

Preparation of Cyclodextrin-Based Carbonaceous Catalyst and Its Application in the Esterification

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Journal of Wuhan university of Technology(Materials Science) 2011年第3期26卷 455-458页

作者：单纯 department of Environmental and Chemical Engineering Shanghai University department of Automation Science Guangdong Polytechnic Normal University

A new carbonaceous catalyst with sulfonic acid group （-SO3H） was prepared by incomplete carbonization of β-cyclodextrin followed by *** sulfonated amorphous carbon was characterized by IR,elemental analysis,DSC-TGA and PXRD,and the catalytic activity was investigated to be an efficient catalyst for the esterification reactions with maximum yield of 87%.The sulfonated carbonaceous catalyst was readily separated from the reaction solution and keeps approximately equal catalytic *** results confirm that the active centre is the hydrophilic sulfonic acid functional group in the esterification reactions.

关键词： β-Cyclodextrin carbonization carbonaceous catalyst esterification activity

THE NONLINEAR BEHAVIOR OF INTERFACE BETWEEN TWO-PHASE SHEAR FLOW WITH LARGE DENSITY RATIOS

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Journal of Hydrodynamics 2006年第5期18卷 587-592页

作者： DONG Yu-hong shanghai Institute of Applied Mathematics and mechanics Shanghai University Shanghai 200072 China

The Navier-Stokes equations for the two-dimensional incompressible flow are used to investigate the effects of the Reynolds number and the Weber number on the behavior of interface between liquid gas shear flow. In the present study, the density ratios are fixed at approximately 10^0-10^3. The interface between the two phases is resolved using the level-set approach. The Reynolds number and the Weber number, based on the gas, are selected as 400-10000 and 40-5000, respectively. In the past, simulations reappeared the amplitude of interface growth predicted by viscous Orr-Sommerfeld linear theory, verifying the applicability and accuracy of the numerical method over a wide range of density and viscosity ratios; now, the simulations show that the nonlinear development of ligament elongated structures and resulted in the subsequent breakup of the heavier fluid into drops.

关键词： two-phase shear flow large density ratios immiscible interface level set approach

An Iterative Formula for the Reflection Coefficient of Multi-layer Thin Film and Its Application in the Design of Optical All Pass Filter

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Chinese Journal of Lasers 2002年第2期11卷 66-70页

作者： MENG Yichao TAN Weihan HUANG Zhaoming( Institute of Communication and Information, shanghai university, shanghai 200072, china department of Physics, shanghai university, shanghai 200436, china) Institute of Communication and Information Shanghai University 上海 200072 department of Physics Shanghai University 上海 200436

In this paper, an iterative formula for the reflection coefficient of the multi-layer thin film is deduced and the design of multi-layer thin film gires-tournois interferometer optical all pass filter(GTI-OAPF) is discussed. The group delay τm ranges from 0. 06 to 460 ps and the bandwidth △ω ranges from 0.068 to 0.0000079 (1015 rad/s). By changing the incident angle θ0, the multi-channel dispersion compensation may be achieved.

关键词： iterative formula for the reflection coefficient optical all pass filter GTI-OAPF

Metalloproteins/metalloenzymes for the synthesis of acetyl-CoA in the Wood-Ljungdahl pathway

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Science china Chemistry 2009年第12期52卷 2071-2082页

作者： ZHU XiaoFei1 & TAN XiangShi1,2 1 department of Chemistry,Fudan university,shanghai 200433,china 2 Institutes of Biomedical Sciences,Fudan university,shanghai 200433,china 1. department of Chemistry Fudan University Shanghai 200433 China 2. Institutes of Biomedical Sciences Fudan University Shanghai 200433 China

This paper focuses on the group of metalloproteins/metalloenzymes in the acetyl-coenzyme A synthesis pathway of anaerobic microbes called Wood-Ljungdahl pathway,including formate dehydrogenase (FDH),corrinoid iron sulfur protein (CoFeSP),acetyl-CoA synthase (ACS) and CO dehydrogenase (CODH). FDH,a key metalloenzyme involved in the conversion of carbon dioxide to methyltetrahydrofolate,catalyzes the reversible oxidation of formate to carbon dioxide. CoFeSP,as a methyl group transformer,accepts the methyl group from CH3-H4 folate and then transfers it to ACS. CODH reversibly catalyzes the reduction of CO2 to CO and ACS functions for acetyl-coenzyme A synthesis through condensation of the methyl group,CO and coenzyme A,to finish the whole pathway. This paper introduces the structure,function and reaction mechanisms of these enzymes.

关键词： Wood-Ljungdahl pathway formate dehydrogenase corrinoid iron sulfur protein acetyl-CoA synthase CO dehydrogenase