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Tree-decompositions of graphs ( I )

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chinese Science Bulletin 1997年第4期42卷 277-281页

作者： SHI Minyonginstitute of Systems Science, chinese academy of sciences beijing 100080, China institute of Systems Science Chinese Academy of Sciences Beijing China

IN this note all graphs are undirected, finite and simple. For a subgraph H of G, V(H), E(H), ε(H) and μ(H) denote the set of vertices, the set of edges, the number of edges in H and the number of cycles in H respectively. H[X] denotes the subgraph of H induced by X. Given two disjoint subsets X and Y of V(G), we write E_G(X, Y)={xy∈E(G)

关键词： tree-decomposition singular vertex maximal planar bipartite graph.

A mixed finite element method for the unilateral contact problem in elasticity

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Science China Mathematics 2006年第4期49卷 513-524页

作者： HUA Dongying & WANG Lieheng The First Fundamental Department, beijing Information Technology institute, beijing 100101, China institute of Computational Mathematics and Scientific/Engineering Computing,{4. of Mathematics and System sciences, chinese academy of sciences, beijing 100080, China 1. The First Fundamental Department Beijing Information Technology Institute Beijing 100101 China 2. institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China

In this paper, we provide a new mixed finite element approximation of the variational inequality resulting from the unilateral contact problem in elasticity. We use the continuous piecewise P2-P1 finite element to approximate the displacement field and the normal stress component on the contact region. Optimal convergence rates are obtained under the reasonable regularity hypotheses. Numerical example verifies our results.

关键词： unilateral contact problem, mixed finite element method.

SYNTHESIS AND PROPERTIES OF ANILING ANILING AND 0-AMINOBENZENESULFONIC ACID COPOLYMER

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chinese Journal of Polymer Science 1999年第2期17卷 165-170页

作者： Jun-hua Fan Mei-xiang Wan Dao-ben Zhu institute of Chemistry, chinese academy of sciences, beijing 100080, China institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Poly(aniline- co-o-aminobenzenesulfonic acid) (PAOABSA) as a water soluble conducting polymerwas synthesized by chemical polymerization. The productivity and the room-temperature conductivity of thecopolymer were measured as a function of the reaction conditions, such as reaction temperature, the ratio ofoxidant to monomer and the degree of sulfonation defined as the ratio of sulfur to nitrogen atoms(S/N). Themain results obtained are summarized as follows : (1) lower reaction temperature (at about 0℃) is favorablefor the enhancement of the room-temperature conductivity of the copolymer; (2) higher content of oxidant isunfavorable for increasing the room-temperature conductivity of the copolymer; (3) both productivity androom-temperature conductivity of the copolymer decrease with increase of the degree of sulfonation whichwas always lower than 0.5 even an excess of o-aminobenzenesulfonic acid was added, probably because thereactivity ratio of aniline (γ=2.99± 0.05) is much higher than that of o-aminobenzenesulfonic acid (γ_2 = 0.06±0.02) estimated by using Fineman-Ross method and least square method.

关键词： Watersoluble polyaniline Reactivity ratio Copolymer

An efficient chiral synthesis of (R)-N-[3-acetyl-4.(2-hydroxy-3-isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science China Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2 & TANG XinLiang1,3 1 Technical institute of Physics and Chemistry,chinese academy of sciences,{4. 100080,China 2 College of Chemistry and Chemical Engineering,Graduate University of chinese academy of sciences,{4. 10004.,China 3 School of Chemical Engineering and Environment,{4. institute of Technology,{4. 100081,China 1. Technical institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China 2. College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. School of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4.(2-hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

SUBSPACE SEARCH METHOD FOR A CLASS OF LEAST SQUARES PROBLEM

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Journal of Computational Mathematics 2000年第2期18卷 133-140页

作者： Zi-Luan Wei (institute of Computational Mathematics and Scientific / Engineerin Computing, chinese academy of sciences, P.O. Box 2719, beijing 100080, China) 中科院计算数学与科学工程计算所北京 100080

Presents information on a study which described a subspace search method for solving a class of least squares problem. Derivation of the algorithm; Convergence results; Modification of algorithm and applications.

关键词： subspace search method A class of least squqres problem convergence analysis.

The Simulation of Influence of Different Coals on the Circulating Fluidized Bed Boiler's Combustion Performance

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Journal of Thermal Science 2003年第2期12卷 185-187,184页

作者： Yumei Yong Qinggang Luinstitute of Engineering Thermophysics, chinese academy of sciences, 100080 beijing, China institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China

The combustion performance of the boiler largely depends on the coal type. Lots of experimental research shows that different fuels have different combustion characteristics. It is obvious that fuel will change the whole operating performance of Circulating Fluidized Bed Combustion (CFBC). We know even in a pilot-scale running boiler, the measurement of some parameters is difficult and costly. Therefore, we developed the way of simulation to evaluate the combustion performance of chinese coals in CFB. The simulation results show that, different coals will result in different coal particle diameter and comminution depending on their mineral component and the change will affect the distribution of ash in CFBC system. In a word, the computational results are in accordance with experimental results qualitatively but there are some differences quantitatively.

关键词： coal circulating fluidized bed combustion simulation.

ELTA-WAVE IN A SIMPLE 1-D 2 x 2 HYPERBOLIC PROBLEM

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Journal of Computational Mathematics 1996年第4期14卷 311-318页

作者： S.L. Yang(institute of Applied Mathematics, chinese academy of sciences, beijing, China) institute of Applied Mathematics Chinese Academy of Sciences Beijing China

A simple one-dimensional 2 x 2 hyperbolic system is considered in the *** model contains a linear hyperbolic equation, as well as a hyperbolic equation ofwhich the coefficients are about the solution of the linear one. The exact solution ispresented and discussed, then numerical experiments are given by TVD (or MmB)type schemes for Riemann problems. From the results, we know that the solutionsdo have δ-waves for some suitable initial data.

关键词： Zhang Figure DELTA-WAVE IN A SIMPLE 1-D 2 HYPERBOLIC PROBLEM

BRST quantization and canonical Ward identity of the supersymmetric electromagnetic interaction system

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Science China(Physics,Mechanics & Astronomy) 2007年第3期50卷 339-347页

作者： HUANG YongChang1,3,4. JIANG YunGuo1 & LI XinGuo2,3 1 institute of Theoretical Physics, College of Applied sciences, beijing University of Technology, beijing 100022, China 2 institute of Modern Physics, chinese academy of sciences, Lanzhou 730000, China 3 Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Collisions, chinese academy of sciences, Lanzhou 730000, China 4.China Center of Advanced Science and Technology (World Laboratory), beijing 100080, China 1. institute of Theoretical Physics College of Applied Sciences Beijing University of Technology Beijing 100022 China 3. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Collisions Chinese Academy of Sciences Lanzhou 730000 China 4. China Center of Advanced Science and Technology (World Laboratory) Beijing 100080 China 2. institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

According to the method of path integral quantization for the canonical constrained system in Becchi-Rouet-Stora-Tyutin scheme, the supersymmetric electromagnetic interaction system was quantized. Both the Hamiltonian of the supersymmetric electromagnetic interaction system in phase space and the quantization procedure were simplified. The BRST generator was constructed, and the BRST transforma- tions of supersymmetric fields were gotten; the effective action was calculated, and the generating functional for the Green function was achieved; also, the gauge generator was constructed, and the gauge transformation of the system was ob- tained. Finally, the Ward-Takahashi identities based on the canonical Noether theorem were calculated, and two relations between proper vertices and propaga- tors were obtained.

关键词： supersymmetric electromagnetic interaction BRST quantization Ward identity

Study on the C_(60)-Caged States of H_2 and N_2

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chinese Chemical Letters 1998年第8期9卷 767-770页

作者： Li Jin XU Chuan Bao ZHU Ji Min YAN(institute of Chemistry, chinese academy of sciences, beijing 100080) chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

The states of small molecule H2 and N2 in the Coo cage have been studied. It is shown that the molecular stable configUrations of the caged states exhibits little change compared with the free states, but the bond int... 详细信息

关键词： C_(60), cage force field caged state, bond intensity