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Plant MITEs: Useful Tools for Plant Genetics and Genomics

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Genomics, Proteomics & Bioinformatics 2003年第2期1卷 90-100页

作者： Ying FengAgriculture and Biotechnology College, zhejiang university, hangzhou 3.0029, china Agriculture and Biotechnology College Zhejiang University Hangzhou 310029 China

MTTEs (Miniature inverted-repeat transposabie elements) are reminiscence ot non-autonomous DNA (class Ⅱ) elements, which are distinguished from other transposable elements by their small size, short terminal inverted repeats (TIRs), high copy numbers, genie preference, and DNA sequence identity among family members. Although MITEs were first discovered in plants and still actively reshaping genomes, they have been isolated from a wide range of eukaryotic organisms. MITEs can be divided into Tourist-like, Stowaway-like, and pogo-like groups, according to similarities of their TIRs and TSDs (target site duplications). In despite of several models to explain the origin and amplification of MITEs, their mechanisms of transposition and accumulation in eukaryotic genomes remain poorly understood owing to insufficient experimental data. The unique properties of MITEs have been exploited as useful genetic tools for plant genome analysis. Utilization of MITEs as effective and informative genomic markers and potential application of MITEs in plants systematic, phylogenetic, and genetic studies are discussed.

关键词： miniature inverted-repeat transposable element MITE transposable element retrotransposon evolution plant

EVOLUTION OF NUMBER CONCENTRATION OF NANO-PARTICLES UNDERGOING BROWNIAN COAGULATION IN THE TRANSITION REGIME

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Journal of Hydrodynamics 2011年第4期23卷 416-421页

作者： WANG Yu-ming LIN Jian-zhong institute of Fluid Measurement and Simulation China Jiliang University Hangzhou 310018 China china Jiliang university Hangzhou 310018 China State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

Evolution of number concentration of nanoparticles undergoing Brownian coagulation in the transition regime is studied theoretically and numerically. The results show that the curves of particle size distribution move toward the area with large particle diameters, the curve peak becomes lower and the range that particle diameters cover becomes wider as time elapses. In the process of coagulation the particles with small diameter disappear gradually and the particle size distribution remains a log-normal distribution. The change rate of the particle size distribution is more appreciable at the initial stage than that at the final stage. The initial Knudsen number has a significant effect on the coagulation rate which increases with decreasing the initial Knudsen number. The larger the initial geometric standard deviation is, the smaller the curve peak is, and the wider the area that curves cover is. The initial geometric standard deviation has a significant effect on the particle size distribution which can remain a self-preserving state when the initial geometric standard deviation is smaller than 2. With the increase of the diversity of initial particle size, the particle size distribution does not obey the log-normal distribution any more as time elapses.

关键词： nanoparticles Brownian coagulation number concentration numerical simulation

STOCHASTIC OPTIMAL CONTROL OF HYSTERETIC SYSTEMS UNDER EXTERNALLY AND PARAMETRICALLY RANDOM EXCITATIONS

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Acta Mechanica Solida Sinica 2003年第1期16卷 61-66页

作者： Ying Zuguang Zhu Weiqiu (Department of Mechanics,zhejiang university,hangzhou 3.0027,china) Department of Mechanics Zhejiang University Hangzhou 310027 China

A stochastic optimal control method for nonlinear hysteretic systems under externally and/or parametrically random excitations is presented and illustrated with an example of hysteretic column system. A hysteretic system subject to random excitation is first replaced by a nonlinear non-hysteretic stochastic system. An It$\hat {\rm o}$ stochastic differential equation for the total energy of the system as a one-dimensional controlled diffusion process is derived by using the stochastic averaging method of energy envelope. A dynamical programming equation is then established based on the stochastic dynamical programming principle and solved to yield the optimal control force. Finally, the responses of uncontrolled and controlled systems are evaluated to determine the control efficacy. It is shown by numerical results that the proposed stochastic optimal control method is more effective and efficient than other optimal control methods.

关键词： stochastic optimal control hysteretic systems random vibration stochastic averaging

SOBOLEV INEQUALITY ON RIEMANNIAN MANIFOLDS

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Chinese Annals of Mathematics,Series B 2005年第4期26卷 651-658页

作者： WANG MENG Department of Mathematics, zhejiang university, hangzhou 3.0027, china School of Mathematical Sciences, Pudan {3., Shanghai 20043., china. Department of Mathematics Zhejiang University Hangzhou 310027 China. School of Mathematical Sciences Fudan University Shanghai 200433 China

Let M be an n dimensional complete Riemannian manifold satisfying the doublingvolume property and an on-diagonal heat kernel estimate. The necessary-sufficientcondition for the Sobolev inequality ‖f‖q ≤ Cn,,v,p,q(... 详细信息

关键词： Sobolev inequality Complete manifold Riesz transform Potential Heat kernel

The maximal super-singular integral operators on product spaces

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Science china Mathematics 2011年第12期54卷 2615-2626页

作者： WANG Hui1 & CHEN JieCheng2,3. 1Department of Mathematics, Xidian university, Xi’an 710071, china 2Department of Mathematics, zhejiang Normal university, Jinhua 3.1004, china 3.epartment of Mathematics, zhejiang university, hangzhou 3.0027, china 1. Department of Mathematics Xidian University Xi’an 710071 China2. Department of Mathematics Zhejiang Normal University Jinhua 321004 China3. Department of Mathematics Zhejiang University Hangzhou 310027 China

We study the maximal super-singular integral operator T＊Ω,α,β（f）（x,y）=sup ∈1〉0,∈2〉0｜∫｜u｜〉ε1,｜v｜〉ε2 b1（｜u｜）b2（｜u｜）Ω（u＇,u＇）/｜u｜^n＋α｜u｜^m＋β-f（x-u,y-u）dudu｜defined on all f ∈ S（R^n ×R^m）, where 0 ≤ α,β〈∞, b1 b2 ∈ L∞（R＋1 ）,Ω satisfies certain cancellation conditions and Ω∈L1（S^n-1×S^m-1）in the case α,β〉0;Ω∈L（log＋L）（S^n-1×S^m-1）in the case αβ=0 and α＋β 〉0. It is proved that, for 1〈p〈∞.T＊Ω,α,βis a bounded operator from the homogeneous Sobolev space Lα,β^p（R^n×R^m）to the Lebesgue space L^p（R^n×R^m）.

关键词： super-singular integral maximal operator product spaces

REACTIVITY RATIOS FOR COPOLYMERIZATION WITH THE PARTICIPATION OF A CHARGE-TRANSFER COMPLEX

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Chinese Journal of Polymer Science 2000年第5期18卷 423-430页

作者： Guo-rong Shan Zhi-xue Weng Zhi-ming Huang Zu-ren Pan institute of Polymer Science and Engineering, zhejiang university, hangzhou 3.0027, {3. zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China

The complexation between styrene (St) and N-phenylmaleimide (PMI) was investigated by H-1-NMR spectroscopy, and the existence of a complex was proved. The equilibrium constant of St/PMI in chloroform at 50 degrees C was determined to be 0.27. New elementary propagation reactions were proposed. On the basis of the propagation elementary reactions for copolymerization with the participation of a charge-transfer complex (CTC), a method for measuring the reactivity ratios is presented. Four reactivity ratios and relative reactivities of free monomer and CTC were obtained. They are r(12) = 0.03., r(21) = 0.012, r(1C) = 0.003., r(2C) = 0.003., and k(1C)/k(12) = 11.3., k(2C)/k(21) = 3.42.

关键词： charge-transfer complex copolymerization reactivity ratio

On Holomorphic Automorphisms of a Class of Non-homogeneous Rigid Hypersurfaces in C^(N+1)

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Chinese Annals of Mathematics,Series B 2010年第2期31卷 201-210页

作者： Qingyan WU Department of Mathematics,Linyi Normal university,Linyi 276005,Shandong,china Department of Mathematics,zhejiang university,{3.,china Department of Mathematics Linyi Normal University Linyi 276005 Shandong China Department of Mathematics Zhejiang University Hangzhou 310027 China

The author determines the real-analytic infinitesimal CR automorphisms of a class of non-homogeneous rigid hypersurfaces in CN+1 near the origin,and the connected component containing the identity transformation of al... 详细信息

关键词： Real-analytic infinitesimal CR automorphisms Rigid hypersurfaces Holomorphic automorphisms

Transport and deposition of nanoparticles in bend tube with circular cross-section

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Progress in Natural Science:Materials International 2009年第1期19卷 33-39页

作者： Peifeng Lin a,Jianzhong Lin a,b,a State Key Laboratory of Fluid Power Transmission and Control,zhejiang university,hangzhou 3.0027,china b china Jiliang university,hangzhou 3.0018,china [a]State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China [b]China Jiliang University Hangzhou 310018 China

Transport and deposition of nanoparticles in bend tube with circular cross-section were simulated numerically for different Reynolds numbers and Dean numbers.A finite-volume code and the SIMPLE scheme were used to solve the *** results show that the distribution of nanoparticle concentration is symmetrical with respect to the top and bottom sides of the *** diameter of the nanoparticles has a weak effect on the distribution of nanoparticle *** maximum and minimum of the deposition enhancement factor occur near the outside and inside walls of the bend tube,*** higher the Reynolds number is,the shorter is the time for nanoparticle *** bend curvature radius has a slight effect on the deposition enhancement factor.

关键词： Nanoparticles Transport Deposition Numerical simulation

FOURIER-CHEBYSHEV COEFFICIENTS AND GAUSS-TURAN QUADRATURE WITH CHEBYSHEV WEIGHT

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Journal of Computational Mathematics 2003年第2期21卷 189-194页

作者： Shijun Yang Xinghua Wang (Department of Mathematics, zhejiang university, hangzhou 3.0028, china) Department of Mathematics Zhejiang University Hangzhou 310028

The main purpose of this paper is to derive an explicit expression for Fourier-Chebyshevcoefficientwhich is initiated by *** and***.

关键词： Fourier-Chebyshev coefficient Gauss-Turan quadrature