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Embed-Solitons and Their Evolutional Behaviors of (3+1)-Dimensional Burgers System

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Communications in Theoretical Physics 2007年第7期48卷 57-62页

作者： ZHU Hai-Ping ZHENG Chun-Long College of Mathematics and Physics,Lishui university,Zhejiang 32.000,{2.2.{2. Institute of Applied Mathematics and Mechanics,{2. university,{2. 2.0072.{2. College of Mathematics and Physics Lishui University Zhejiang 323000 China shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

With the help of an extended mapping approach and a linear variable separation method,new families ofvariable separation solutions with arbitrary functions for the(3+1)-dimensional Burgers system are *** onthe derived exact solutions, some novel and interesting localized coherent excitations such as embed-solitons are revealedby selecting appropriate boundary conditions and/or initial *** time evolutional properties of the novellocalized excitation are also briefly investigated.

关键词： extended mapping method (3+1)-dimensional Burgers system embed-soliton evolutional behavior

Automorphisms with order three of affine Lie algebras

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Chinese Science Bulletin 1998年第21期43卷 1793-1798页

作者： JIN Quanqin 1,2.and HOU Zixin 2.1. Department of Mathematics, Hebei {2., Baoding 071002. china 2. Department of Mathematics, Nankai {2., Tianjin 300071, china Department of Mathematics Hebei University Baoding China Department of Mathematics Nankai University Tianjin China

Some properties of automorphisms of affine Lie algebras are presented. Automorphisms with order three are classified up to conjugacy, and their fixed point sets are also computed. As a corollary, it is proved that two... 详细信息

关键词： affine Lie algebra automorphism of order three first (second) kind of automorphism.

DEVELOPMENT OF TWO-DIMENSIONAL HYDRODYNAMIC AND WATER QUALITY MODEL FOR HUANGPU RIVER

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Journal of Hydrodynamics 2003年第2期15卷 1-11页

作者： Xu Zu xin, Yin Hai longState Key Laboratory of pollution Control and Resource Reuse, tongji university, shanghai 2.0092. china Lab. of Pollution Control Tongji Univ. Shanghai 200092 China

Based on numerical computation model RMA2.and RMA4 with open source code,finite element meshes representing the study domain are created, then the finite elementhydrodynamic and water quality model for Huangpu River is developed and calibrated, and thesimulation results are analyzed. This developed hydrodynamic and water quality model is used toanalyze the influence of discharged wastewater from planning Wastwater Treatment Plant (WWTP) onHuangpu River's water quality.

关键词： huangpu river water quality finite element method wastwater treatment plant

Chinese Jingdezhen blue and white imperial porcelain

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Science china(Technological Sciences) 2004年第3期47卷 366-375页

作者： WU Juan1, LI Jiazhi1, DENG Zequn1 & WANG Changsui2.1. Laboratory of Ancient Ceramics, shanghai Institute of Ceramics, Chinese Academy of Sciences, shanghai 2.0050, {2. 2. Department of History of Science and Archaeometry, university of Science and Technology of {2., Hefei 2.002., {2. Laboratory of Ancient Ceramics Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China Department of History of Science and Archaeometry University of Science and Technology of China Hefei 230026 China

Jingdezhen blue and white imperial porcelain specimens from the Yuan, Ming and Qing dynasties have been systematically analyzed using a nondestructive test method—— energy dispersive X-ray fluorescence analysis (EDXRF). The derived data of major and trace element compositions have been treated by correspondence analysis. The variation laws of the composition patterns for Jingdezhen blue and white imperial porcelain in different historical periods owing to the change in raw materials, recipe and technology have been discussed, and a time model related to variation of element composition has been preliminarily established, It would be helpful for scientific dating of Jingdezhen blue and white imperial porcelain, and even for the studies on the whole field of identification of ancient ceramics.

关键词： energy dispersive X-ray fluorescence analysis, blue and white imperial porcelain, correspondence analysis.

Sharpness on the Lower Bound of the Lifespan of Solutions to Nonlinear Wave Equations

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Chinese Annals of Mathematics,Series B 2011年第4期32卷 521-526页

作者： Yi ZHOU 1 Wei HAN 2.1 Nonlinear Mathematical Modeling and Methods Laboratory shanghai Key Laboratory for Contem- porary Applied Mathematics School of Mathematical Sciences, Fudan {2., shanghai 2.0433, china. 2.School of Mathematical Sciences, Fudan {2., shanghai 2.0433, china Department of Mathematics, North {2. of china, Taiyuan 030051, china. Nonlinear Mathematical Modeling and Methods Laboratory shanghai Key Laboratory for Contemporary Applied Mathematics School of Mathematical Sciences Fudan University Shanghai China School of Mathematical Sciences Fudan University Shanghai China Department of Mathematics North University of China Taiyuan China

This paper is devoted to proving the sharpness on the lower bound of the lifespan of classical solutions to general nonlinear wave equations with small initial data in the case n = 2.and cubic nonlinearity （see the results of T. T. Li and Y. M. Chen in 1992.. For this purpose, the authors consider the following Cauchy problem： { where □=δt^2.∑i=1n δx^^2. is the wave operator, g（x）（≡/） 0 is a smooth non-negative function with compact support, and ε 〉 0 is a small parameter. It is shown that the solution blows up in a finite time, and the lifespan T（ε） of solutions has an upper bound T（ε） ≤ exp（Aε-2. with a positive constant A independent of ε, which belongs to the same kind of the lower bound of the lifespan.

关键词： Nonlinear wave equation Cauchy problem Lifespan

A study of mechanical behavior of rock-fill materials with reference to particle crushing

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Science china(Technological Sciences) 2007年第Z1期50卷 125-135页

作者： HUANG WenXiong1?, REN QingWen1 & SUN DeAn2.1 Department of Engineering Mechanics, Hohai university, Nanjing 2.0098, china 2.Department of Civil Engineering, {2. university, {2. 2.0072. china Department of Engineering Mechanics Hohai University Nanjing China Department of Civil Engineering Shanghai University Shanghai China

In rock-fill dams of 2.0 to 300 m high, maximum compressive stress can exceed 6 MPa. At such a high stress level, rock-fill materials may experience particle crushing during shear. The material behavior is highly sophisticated exhibiting pressure and density dependency as well as particle crushing effects. Through scrutinizing the relevant experimental data on rock-fill materials and sands published in the literatures, this paper is focused on understanding basic mechanical characteristics of this sort of materials in the light of constitutive modelling.

关键词： rock-fill materials granular materials compressibility shear dilatancy particle crushing

Density functional study on enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine

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Science china Chemistry 2006年第4期49卷 296-307页

作者： LI Ming1, ZHENG Wenxu2.& TIAN Anmin2.1. Department of Chemistry, Southwest-{2. Normal university, Chongqing 400715, {2. 2. Department of Chemistry, Sichuan university, Chengdu 610064, {2. Department of Chemistry Southwest-China Normal University Chongqing China Department of Chemistry Sichuan University Chengdu China

The enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine is discussed by the density functional theory (DFT) method. The main intermediates and transition states for this reaction are optimized completely at the B3LYP/6-31g(d) level, and the transition states are verified by vibrational modes. As shown, the chirality-controlled steps for this re- action are the hydride transfer from borane to carbonyl carbon and oxime carbon of keto oxime ether, and the chirality for the reduced products is determined in these two reaction steps. In all examined reaction paths, the first hydride is transferred via a six-membered ring and the second hydride via a five-membered ring or a four-membered ring.

关键词： keto oxime ether, oxazaborolidine, enantioselective reduction, DFT.

Phase transition in the Zr_(60)Al_(15)Ni_(2.) bulk metallic glass subjected to rolling at room temperature

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Science china(Technological Sciences) 2006年第6期49卷 655-662页

作者： YAN Zhijie1, 2. LI Jinfu1, ZHOU Yaohe1 & WU Yanqing3 1. State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, shanghai Jiao Tong {2., shanghai 2.0030, china 2. School of Materials Science and Engineering, Taiyuan {2. of Science and Technology, Taiyuan 03002., china 3. School of Environmental Science and Engineering, shanghai Jiao Tong {2., shanghai 2.0030, china State Key Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai China School of Materials Science and Engineering Taiyuan University of Science and Technology Taiyuan China School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai China

The microstructure evolution of the Zr60Al15Ni2. metallic glass during rolling at room temperature is investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC); high-resolution transmission electron microscopy (HREM). The results show that the values of full width at half maximum (FWHM) of the XRD patterns; exothermic enthalpy ΔH of DSC plots do not monotonically change with the variation of deformation degrees . As is not large than 2.%, the values of FWHM; ΔH are lower than that of the as-cast state. When reaches 30%, the values of FWHM; ΔH become larger than that of the as-cast state, while their values begin to decrease again as reaches about 85%. These results indicate that the reversible transitions between ordered; disordered atomic configurations occur during rolling, which is further verified by the HREM images. The reversible phase transition can be explained by the competition between the diffusion controlled reordering; shear-induced disordering during rolling.

关键词： metallic glasses, plastic deformation, phase transformations, shear bands.

Perturbations of the radical of nest algebras

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Chinese Science Bulletin 1998年第7期43卷 556-560页

作者： LU Fangyan 1 and LU Shijie 2.1. Department of Mathematics, Suzhou university, Suzhou 2.5006, china 2. Department of Mathematics, Zhejiang university, Hangzhou 31002., china Department of Mathematics Suzhou University Suzhou China Department of Mathematics Zhejiang University Hangzhou China

Let R N and K-N be the radical ideal and the compact operator ideal of nest algebra T(N) respectively. It is proved thatR-N+K-N=span{T∈T(N)∶TT(N)NCT}=span{T∈T(N): #σ′(ST)≤1, S∈T(N)}.

关键词： nest algebras radical perturbation.