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The complex variable reproducing kernel particle method for elasto-plasticity problems

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Science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 954-965页

作者： CHEN Li1 & CHENG YuMin2.1 Department of Engineering Mechanics,Chang’an university,Xi’an 710064,china 2.Shanghai {2. of applied Mathematics and Mechanics,Shanghai university,Shanghai 2.0072.china 1. Department of Engineering Mechanics Chang’an University Xi’an 710064 China2. Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

On the basis of reproducing kernel particle method(RKPM),using complex variable theory,the complex variable reproducing kernel particle method(CVRKPM) is discussed in this *** advantage of the CVRKPM is that the correction function of a two-dimensional problem is formed with one-dimensional basis function when the shape function is *** the CVRKPM is applied to solve two-dimensional elasto-plasticity *** Galerkin weak form is employed to obtain the discretized system equation,the penalty method is used to apply the essential boundary *** then,the CVRKPM for two-dimensional elasto-plasticity problems is formed,the corresponding formulae are obtained,and the Newton-Raphson method is used in the numerical *** numerical examples are given to show that this method in this paper is effective for elasto-plasticity analysis.

关键词： meshless method reproducing kernel particle method(RKPM) complex variable reproducing kernel particle method(CVRKPM) correction function elasto-plasticity

A pulse radiolysis study on electron affinity of piperonal

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Science china chemistry 2005年第5期48卷 476-480页

作者： MA Jianhua1, LIN Weizhen2. WANG Wenfeng2.& YAO Side2.1. College of Biology Engineering, Jimei university, Xiamen 36102., china 2. Shanghai {2. of applied Physics, Chinese Academy of Sciences, Shanghai 2.1800, china 1. College of Biology Engineering Jimei University 361021 Xiamen China 2. Shanghai institute of applied Physics Chinese Academy of Sciences 201800 Shanghai China

The piperonal electron affinity was studied using pulse radiolysis technique. The electron transfer reaction process between piperonal and anthraquinone-2.sulfate was observed in the pH 7 phosphoric acid salt buffer. The transient absorption spectra of electron transfer re-action between piperonal and anthraquinone-2.sulfate were obtained, and the initial proof of the electron transfer between electron donor and acceptor was provided directly. The one-electron reduction potential of piperonal was determined to be ?0.457 V.

关键词： piperonal, pulse radiolysis, one-electron reduction potential.

Mineralogy and crystal structure determination of Mg-fillowite

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Science china Earth Sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1 , SHI Nicheng 1 & YE Danian 2.1. china university of Geosciences, Beijing 100083, china 2. institute of Geology, Chinese Academy of Sciences, Beijing 10002., china 1. china university of Geosciences 100083 Beijing China 2. institute of Geology Chinese Academy of Sciences 100029 Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2.a(Mn4Mg2.e)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, xinjiang, china. It is of the trigonal lattice, with space group R-3, unit cell a=1.5143(3) nm, c=4.3191(2. nm, V=8.5736 nm3, Z = 18. The R-factor of the determination accuracy is R (I > 2. ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 72. atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

Empirical Analysis of xinjiang's Bilateral Trade: Gravity Model Approach

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Chinese Geographical Science 2008年第1期18卷 9-16页

作者： CHEN Xuegang YANG Zhaoping LIU Xuling xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Graduate university of the Chinese Academy of Sciences Beijing 100049 China

Based on the basic trade gravity model and xinjiang's practical situation, new explanatory variables (GDP, GDPpc and SCO) are introduced to build an extended trade gravity model fitting for xinjiang's bilateral trade. From the empirical analysis of this model, it is proposed that those three variables affect the xinjiang's bilateral trade posi- tively. Whereas, geographic distance is found to be a significant factor influencing xinjiang’s bilateral trade negatively. Then, by the extended trade gravity model, this article analyzes the present trade situation between xinjiang and its main trade partners quantitatively in 2.04. The results indicate that xinjiang cooperates with its most trade partners successfully in terms of present economic scale and developing level. xinjiang has established successfully trade part- nership with Central Asia, Central Europe and Eastern Europe, Western Europe, East Asia and South Asia. However, the foreign trade development with West Asia is much slower. Finally, some suggestions on developing xinjiang's for- eign trade are put forward.

关键词： trade gravity model extended trade gravity model bilateral trade Shanghai Cooperation Organization (SCO) xinjiang

In-situ FTIR Spectroelectrochemical Study of Chromium Hexacyanoferrate on Glassy Carbon Electrode

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Chinese Chemical Letters 1998年第9期9卷 851-854页

作者： Ai Li BO (Laboratory of Electroanalytical chemistry, Changchun institute of {2. chemistry, ChineseAcademy of Sciences, Changchun 13002.) Xiang Qin LIN (Department of chemistry, university of Science and Technology of china, Hefei 2.002.) Chinese Acad Sci Changchun Inst Appl Chem Electroanalyt Chem Lab Changchun 130022 Peoples R China Univ Sci & Technol china Dept Chem Hefei 230026 Peoples R China

Chromium hexacyanoferrate (CrHCF) modified grassy carbon electrode (GC) in different electrolytes was studied by cyclic voltammetry and in situ FTIR spectroelectrochemistry. The results indicate that the behavior of CrHCF firm can be understood in term of two structures: Cr1/3Cr(III)Fe(II)(CN), and MCr(III)Fe(II)(CN)(6). Besides,the film exists in amorphous state: the outer layer is porous film, while the inner layer is relatively compact. According to the electrochemical reaction of CrHCF, the lattice can contract and expand with the cations' diffusion.

关键词： chromium hexacyanoferrate grassy carbon electrode electrochemistry in situ FTIR spectroelectrochemistry

On two transverse nonlinear models of axially moving beams

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Science china(Technological Sciences) 2009年第3期52卷 743-751页

作者： DING Hu1 & CHEN LiQun1,2.1 Shanghai institute of applied Mathematics and Mechanics, Shanghai {2., Shanghai 2.0072. china 2.Department of Mechanics, Shanghai {2., Shanghai 2.0444, china 1. Shanghai institute of applied Mathematics and Mechanics Shanghai University Shanghai 200072 China 2. Department of Mechanics Shanghai University Shanghai 200444 China

Nonlinear models of transverse vibration of axially moving beams are computationally investigated. A partial-differential equation is derived from the governing equation of coupled planar motion by omit- ting its longitudinal terms. The model can be reduced to an integro-partial-differential equation by av- eraging the beam disturbed tension. Numerical schemes are respectively presented for the governing equations of coupled planar and the two governing equations of transverse motion via the finite dif- ference method and differential quadrature method under the fixed boundary and the simple support boundary. A steel beam and a copper beam are treated as examples to demonstrate the deviations of the solutions to the two transverse equations from the solution to the coupled equation. The numerical results indicate that the differences increase with the amplitude of vibration and the axial speed. Both models yield almost the same precision results for small amplitude vibration and the inte- gro-partial-differential equation gives better results for large amplitude vibration.

关键词： axially moving beam nonlinearity transverse vibration finite difference method differential quadrature method

Kumada chain-growth polycondensation as a universal method for synthesis of well-defined conjugated polymers

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Science china chemistry 2010年第8期53卷 1620-1633页

作者： GENG YanHou1,HUANG Li1,2.WU ShuPeng1,2.& WANG FoSong1 1State Key Laboratory of Polymer Physics and chemistry Changchun institute of {2. chemistry,Chinese Academy of Sciences,Changchun 13002.,china 2.raduate university of Chinese Academy of Sciences,Beijing 100049,china 1. State Key Laboratory of Polymer Physics and chemistry Changchun institute of applied {2. Chinese Academy of Sciences Changchun 130022 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Kumada chain-growth polycondensation (KCGP) is a novel method for the synthesis of well-defined conjugated *** the Ni-catalyst can transfer in an intramolecular process to the propagating chain end,the polymerization follows chain-growth *** this newly developed method,various conjugated polymers,such as polythiophenes,poly(p-phenylene) (PPP),polypyrrole (PPy),and polyfluorene with controlled molecular weights and relatively narrow polydispersities (PDIs),have been ***,the polymerizations for poly(3-alkylthiophene)s (P3ATs),PPP,and PPy exhibited quasi-living characteristics,which allows preparing polymer brushes,fully-conjugated block copolymers,and macroinitiators and macro-reactants for the synthesis of rod-coil block *** the current review,the progress in this new area is summarized.

关键词： chain growth polycondensation conjugated polymers Kumada reaction block copolymers polymer brush

MIXED FINITE ELEMENT METHODS FOR A STRONGLYNONLINEAR PARABOLIC PROBLEM

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Journal of Computational Mathematics 1999年第2期17卷 209-220页

作者： Yan-ping Chen(Department of Mathematics, Nanjing university, Naming 2.0008, china {2. ofComputational and applied Mathematics, Xiangtan university, Hunan 411105, china) 南京大学数学系江苏南京

A mixed finite element method is developed to approximate the solution of a strongly nonlinear second-order parabolic problem. The existence and uniqueness of the approximation are demonstrated and L-2.error estimates... 详细信息

关键词： finite element method nonlinear parabolic problem

The possible pivotal role of the eastward dust transport from Central Asia in the global temperature decrease

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Chinese Science Bulletin 2006年第A01期51卷 1-7页

作者： LIU Mingzhe & WEI Wenshou xinjiang institute of Ecology and Geography, Chinese Academy of Sciences, {2. 830011, china Graduate university of the Chinese Academy of Sciences, Beijing 100039, china Chemical Laboratory for Atmosphere, china Meteorological Administration, Beijing 100081, china {2. Desert Meteorology, china Meteorological Administration, {2. 830002. china Grad Univ Chinese Acad Sci Beijing 100039 Peoples R China china Meteorol Adm Chem Lab Atmosphere Beijing 100081 Peoples R China china Meteorol Adm Urumqi 830002 Peoples R China Chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China

glacial-interglacialgyrations 的出现能与 Milankovitch 理论被解释，这通常被考虑。然而，在理论的一些问题的答案还当前没被导出。在从 CentralAsia 研究东方灰尘运输以后，我们发现了在东方灰尘运输和全球温度减少之间有积极反馈... 详细信息

glacial-interglacialgyrations 的出现能与 Milankovitch 理论被解释，这通常被考虑。然而，在理论的一些问题的答案还当前没被导出。在从 CentralAsia 研究东方灰尘运输以后，我们发现了在东方灰尘运输和全球温度减少之间有积极反馈机制。这在北半球的 thehigh 纬度区域放大太阳的放射变化的效果，并且导致全球冰川的时代的出现。积极反馈机制在北半球的 thehigh 纬度区域以太阳的放射的减小开始。随后，全球温度减少，全球冰川的历元发生，在哪个枢轴的因素是从 CentralAsia 的东方灰尘运输。与积极反馈机制的理论，在 Milankovitch 理论的一些问题能被解决很好。

关键词：冰川间冰期高纬度地区北半球太阳辐射正反馈机制