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Theoretical study on the reaction mechanism of(CH_3)_3CO+CO

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Science china Chemistry 2005年第1期48卷 18-24页

作者： ZHAO Hongmei1,2.3, SUN Chengke1,4, ZHANG Rongchang3, XI Hongmin3 & LI Zonghe1 1. department of Chemistry, beijing {2. University, beijing 100875, china 2. The Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, beijing 100080, china 3. department of Chemistry, Beihua University, Jilin 132.13, china 4. department of Chemistry, Qujing {2. University, Yunnan 655000, china 1. department of Chemistry Beijing Normal University 100875 Beijing China 2. The Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 3. department of Chemistry Beihua University 132013 Jilin China 4. department of Chemistry Qujing Normal University 655000 Yunnan China

The reaction mechanism of (CH3)3CO with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3LYP/6-31G* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-31++G** level. The results show that the reaction is multi-channel and the reaction of (CH3)3CO radical with CO mostly produces (CH3)3C + CO2. The reaction could play a role in eliminating air pollution.

关键词： DFT, B3LYP, (CH3)3CO, radical.

|m| Partial wave treatment for two-dimensional Coulomb-scattering and Regge pole

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Science china(physics,Mechanics & Astronomy) 2004年第6期47卷 676-684页

作者： WANG Jing & ZENG Jinyan department of physics,Tsinghua University,{2. 100084,china School of physics,Peking University,{2. 100871,china department of physics Tsinghua University Beijing 100084 China School of physics Peking University Beijing 100871 China

The symmetry and |m| partial-wave analysis for two-dimensional (2.) Coulomb-scattering is investigated. As a function of energyE, the |m| partial-wave scattering amplitudef |m|(θ) is analytically continuated to the, negativeE (complexk) plane, and it is found that the bound state energy eigenvalues (E<0) are just located at the poles off |m|(θ) on the positive imaginaryk axis as is expected. In addition, as a function of |m|,f |m|(θ) is analytically continuated to the complex |m| plane, the bound state energy eigenvalues are just located at the poles off |m|(θ) on the positive real |m| axis.

关键词： two-dimensional Coulomb scattering, |m| partial-wave, Regge pole.

EXISTENCE AND ASYMPTOTIC BEHAVIOR OF THE SOLUTIONS FOR A NONLINEAR ELLIPTIC EQUATION ARISING IN ASTROphysics

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Acta Mathematica Scientia 2006年第2期26卷 229-245页

作者：唐仲伟 School of Mathematical Sciences beijing normal University Beijing 100875China

The author first analyzes the existence of ground state solutions and cylindrically symmetric solutions and then the asymptotic behavior of the ground state solution of the equation -△u =φ（r）u^p-1, u 〉 0 in R^N, u ∈ D^1,2.R^N）, where N ≥ 3, x = （x^1,z） ∈ R^K×R^N-K,2.≤ K ≤ N,r = ｜x′｜. It is proved that for 2.N-s）/（N-2. 〈 p 〈 2.＊ = 2./（N - 2., 0 〈 s 〈 2. the above equation has a ground state solution and a cylindrically symmetric solution. For p = 2.＊, the above equation does not have a ground state solution but a cylindrically ***, and when p close to 2.＊, the ground state solutions are not cylindrically symmetric. On the other hand, it is proved that as p close to 2., the ground state solution Up has a unique maximum point xp = （x′p, Zp） and as p → 2.＊, ｜x′p｜ → r0 which attains the maximum of φ on R^N. The asymptotic behavior of ground state solution Up is also given, which also deduces that the ground state solution is not cylindrically symmetric as p goes to 2.＊.

关键词： Cylindrical symmetry asymptotic behavior ground state solution

A Novel Synthesis of Isoxazole Derivatives

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Chinese Chemical Letters 1998年第9期9卷 801-802页

作者： Jun Feng WANG Bao Shan DU Qing Hua CHEN (department of Chemistry, beijing {2. University, beijing 100875) beijing normal Univ Dept Chem Beijing 100875 Peoples R China

The new synthetic method of isoxazole derivatives was succesfully achieved. The experimental results demonstrate that thermal decomposition reactions of nitrone could take place with yields of 41 similar to 81%, to gi... 详细信息

关键词： nitrone isoxazole

Asymmetric 1,3-Dipolar Cycloaddition of the Chiral Nitronic Esters with Acrylate

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Chinese Chemical Letters 1997年第12期8卷 0-0页

作者： Fu An KANG and Cheng Lie Ym(department of Chemiscy Beijtw normal Unthersho{2.) department of Chemistry Beijing Normal University Beijing 100875 China

Asymmetric 1,3-dipolar cycloaddihon of the chiral nitronic esters with acrylate giving the enantiomerically pure novel chiral bisheterocyclic compounds is describcd

关键词： Asymmetric 1 3-Dipolar Cycloaddition of the Chiral Nitronic Esters with Acrylate

Difference discrete connection and curvature on cubic lattice

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Science china Mathematics 2006年第11期49卷 1458-1476页

作者： WU Ke, ZHAO Weizhong & GUO Hanying department of Mathematics, Capital normal University, {2. 100037, china Institute of Theoretical physics, Chinese Academy of Sciences, {2. 100080, china 1. department of Mathematics Capital Normal University Beijing 100037 China 2. Institute of Theoretical physics Chinese Academy of Sciences Beijing 100080 China

In a way similar to the continuous case formally, we define in different but equivalent manners the difference discrete connection and curvature on discrete vector bundle over the regular lattice as base space. We deal with the difference operators as the discrete counterparts of the derivatives based upon the differential calculus on the lattice. One of the definitions can be extended to the case over the random lattice. We also discuss the relation between our approach and the lattice gauge theory and apply to the discrete integrable systems.

关键词： discrete connection, discrete curvature, noncommutative calculus, lattice gauge theory, discrete Lax pair.

HIGH-ENERGY PROTON IRRADIATION EFFECTS ON GaAs/Ge SPACE SOLAR CELLS

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 463-466页

作者： R. Wang (The Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Institute of Low Energy Nuclear physics, beijing {2. University beijing Radiation Center, beijing 100875, china) S.D. Yao (department of Technical Phys Inst. of Energy Nucl. Phys. Beijing Normal Univ. Beijing 100875 China

This paper reports the high-energy proton irradiation effects on GaAs/Ge space solar cells. The solar cells were irradiated by protons with energy of 5-2. MeV at fluence ranging from 1×109 to 7×1013 cm-2. and then their electric parameters were measured at AM0. It was shown that the Isc, Voc and Pmax decrease as the proton energy increasing, and the degradation is relative to proton irradiation-induced defect with a level of Ec-0.41 eV in irradiated GaAs/Ge cells.

关键词： Germanium High energy physics Irradiation Protons Semiconducting gallium arsenide

Molecular structure and biological function of proliferating cell nuclear antigen

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Progress in Natural Science:Materials International 2007年第10期17卷 1127-1135页

作者： Song Nanmeng1, Sang Jianli1 and Xu Heng2.1. Institute of Cell Biology, College of Life Science, beijing normal University,{2., china 2. Emory University School of Medicine, GA 30332. USA) Institute of Cell Biology College of Life Science Beijing Normal University Beijing 100875， China Emory University School of Medicine GA 30332 USA

Proliferating cell nuclear antigen (PCNA) is the core component of replication complex in eukaryote. As a processive factor of DNA polymerase delta, PCNA coordinates the replication process by interacting with various replication proteins. PCNA appears to play an essential role in many cell events, such as DNA damage repair, cell cycle regulation, and apoptosis, through the coordination or organization of different partners. PCNA is an essential factor in cell proliferation, and has clinical significance in tumor research. In this article we review the functional structure of PCNA, which acts as a function switch in different cell events.

关键词： PCNA Function Switch PCNA Binding Motif Cell Cycle DNA Replication DNA Repair.

An ideal interval method of multi-objective decision-making for comprehensive assessment of water resources renewability

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Science china(Technological Sciences) 2004年第z1期47卷 42-50页

作者： YANG Xiaohua1, YANG Zhifeng1,2. SHEN Zhenyao1 & LI Jianqiang3 1. School of Environment, State Key Laboratory of Water Environment Simulation, beijing normal Univer- sity,{2., china 2. School of Environment, Key Laboratory for Water and Sediment Sciences of Ministry of Education, beijing normal University,{2., china 3. Water Resources and Hydropower Planning and Design General Institute, MWR, beijing 100011, china beijing normal Univ Sch Environm State Key Lab Water Environm Simulat Beijing 100875 Peoples R China beijing normal Univ Sch Environm Key Lab Water & Sediment Sci Minist Educ Beijing 100875 Peoples R China MWR Water Resources & Hydropower Planning & Design Ge Beijing 100011 Peoples R China

In order to estimate water resources renewability scientifically, an Ideal Interval Method of Multiple Objective Decision-Making (IIMMODM) is presented. This method is developed through improving an ideal point method of multiple objective decision-making. The ideal interval is obtained with assessment standard instead of ideal points. The weights are decided by using the basic point and gray code accelerating genetic algorithm. This method has synthesized the expert’s suggestion and avoided giving a mark for the objective again. It could solve the complicated problem of compatible or incompatible multi-objective assessment. The principle of IIMMODM is presented in this paper. It is used to assess the water resources renewability for nine administrative divisions in the Yellow River basin. The result shows that the water resources renewability in the Yellow River basin is very low. Compared with the gray associate analysis method, fuzzy synthesis method and genetic projection pursuit method, the IIMMODM is easier to use. Compared with the ideal point method of multiple objective decision-making, the IIMMODM has good robustness, which is applicable to the comprehensive assessments of water resources.

关键词： water resources renewability, comprehensive assessment, multiple objective decision-making,ideal interval, Yellow River basin.