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Theoretical study of the interaction mechanism of single-electron halogen bond complexes H_3C…Br-Y(Y=H,CN,NC,CCH,C_2._3)

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Science China Chemistry 2010年第1期53卷 216-225页

作者： LI ZhiFeng1,SHI XiaoNing1,TANG HuiAn1 & ZHANG JunYan2.1College of Life Science and Chemistry,Tianshui normal university,Tianshui 741001,China 2.anzhou {2. of Chemical physics,Chinese Academy of Sciences,Lanzhou 730000,China 1. College of Life Science and Chemistry Tianshui Normal University Tianshui 741001 China2. Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The characteristics and structures of single-electron halogen bond complexes H3C…Br-Y(Y = H,CCH,CN,NC,C2.3) have been investigated by theoretical calculation *** geometries were optimized and frequencies calculated at the B3LYP/6-311++G *** interaction energies were corrected for basis set superposition error(BSSE) and the wavefunctions obtained by the natural bond orbital(NBO) and atom in molecule(AIM) analyses at the MP2.6-311++G *** each H3C…Br-Y complex,a single-electron Br bond is formed between the unpaired electron of the CH3(electron donor) radical and the Br atom of Br-Y(electron acceptor);this kind of single-electron bromine bond also possesses the character of a"three-electron bond".Due to the formation of the single-electron Br bond,the C-H bonds of the CH3 radical bend away from the Br-Y moiety and the Br-Y bond elongates,giving red-shifted single-electron Br bond *** effects of substituents,hybridization of the carbon atom,and solvent on the properties of the complexes have been *** strengths of single-electron hydrogen bonds,single-electron halogen bonds and single-electron lithium bonds have been *** addition,the single-electron halogen bond system is discussed in the light of the first three criteria for hydrogen bonding proposed by Popelier.

关键词： single-electron halogen bond single-electron hydrogen bond single-electron lithium bond MP2 DFT NBO AIM

Effect of excess Y_2._3 addition on the physical properties of melt processed YBCO bulks

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Science China(physics,Mechanics & Astronomy) 2004年第1期47卷 17-23页

作者： YANG Wanmin1,2.3, ZHOU Lian2. FENG Yong2. ZHANG Pingxiang2. WU Minzhi3 & W. GAWALEK3 1. Department of physics, Shaanxi {2. university, Xi抋n 710062. China 2. Northwest institute for Nonferrous Metal Research. Xi抋n 710016, China 3. institute fur Physikalische Hochtechnologie e.V(IPHT), Jena, Germany Correspondence should be addressed to Yang Wanmin (email: wm-yang@***) Received June 2., 2.03 1. Department of physics Shaanxi Normal University 710062 Xi’an China 2. Northwest institute for Nonferrous Metal Research 710016 Xi’an China 3. institute fur Physikalische Hochtechnologie e.V (IPHT) Jena Germany

The YBCO superconductors with Y2.3 addition were prepared by a modified melt textured process and the effects of excess Y2.3 addition on the physical properties of melt textured YBCO have been investigated. It is found that the melt temperature of YBCO samples decreases drastically with the increasing Y2.3, and the maximum levitation forces are drastically different for samples with different Y2.3 addition. It is also found that the optimal Y2.3 addition to YBCO is about 10wt%. Considering the microstructure and the starting composition, the results are well discussed and interpreted.

关键词： YBCO superconductor, melt growth, Y2.3 addition, levitation force.

The study of energy bands in nucleus ^(102.Zr

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Science China(physics,Mechanics & Astronomy) 2010年第1期53卷 106-110页

作者： DONG GuoXiang 1,2., YU ShaoYing 1,2.3 , LIU YanXin 1 , SHEN CaiWan 1,2.4 & DONG YongSheng 1,2.5I School of Science, Huzhou Teachers College, Huzhou 313000, China 2.School of Science and Information Engineering, Zhejiang normal university, Jinhua 32.000, China 3 {2. of Theoretical physics, Chinese Academy of Sciences, Beijing 100080, China 4 Center of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000, China 5 Department of physics, Jining Teachers College, Jining 012.00, China 1. School of Science Huzhou Teachers College Huzhou 313000 China2. School of Science and Information Engineering Zhejiang Normal University Jinhua 321000 China3. Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China4. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China5. Department of Physics Jining Teachers College Jining 012000 China

Theoretical calculations of the energy bands in nucleus 102.Zr are carried out by taking the projected shell model approach, which has reproduced the experimental data. In addition, by analyzing band-head energies, corresponding configurations of yrast band, quasi-particle rotational bands and side bands, we have worked out the microscopic formation mechanism of axially symmetric deformation bands: The low-excitation deformation bands are attributed to the high-j intruder states 1g 7/2.and 1h 11/2.in the N=4, 5 shells; the quasi-particles in the orbit v5/2.[532., v3/2.[411] and v3/2.[413] in particular play an important role in the deformation of 102.Zr.

关键词： projected shell model yrast band quasi-particle rotational band side band

The numerical method for three-dimensional impact with friction of multi-rigid-body system

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Science China(physics,Mechanics & Astronomy) 2006年第1期49卷 102-118页

作者： ZHAO Zhen1,2. LIU Caishan2.& CHEN Bin2.1. Beijing institute of Graphic Communication, Beijing 102.00, China 2. Department of Mechanics & Engineering Science, Peking {2., Beijing 100871, China Beijing institute of Graphic Communication Beijing 102600 China Department of Mechanics & Engineering Science Peking University Beijing 100871 China

The differential equations for planar impacts reduce to an algebraic form, and can be easily solved. For three dimensional impacts with friction, there is no closed-form solution, and numerical integration is required due to the swerve behavior of tangential impulse during collisions. The dynamic governing equations in the impact process are built up in impulse space based on the Lagrangian equation in this paper. The coefficient of restitution defined by Poisson is used as the condition of impact termination. A valid nu- merical method for solving three-dimensional frictional impact of multi-rigid body system is established. The singular cases of tangential movement in sticking point are especially noticed and analyzed. Several examples are present to reveal the different kinds of tan- gential movement modes varied with the normal impulse during collision.

关键词： multi-rigid body, impact, friction.

STEREOSPECIFIC POLYMERIZATION OF STYRENE WITH MODIFIED TiCl4/MgCl2.AlEt3 CATALYST

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Chinese Journal of Catalysis 1998年第6期 8-9页

作者： Sun Qi 1,2. , Fan Yinheng 1,2. , Liu Jing 1, Liao Shijian 1** (1 Dalian institute of Chemical physics, The Chinese Academy of Sciences, Dalian 11602. 2. D{2. of Chemistry, Liaoning normal university, Dalian 11602.)

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关键词： Styrene Polymerization Supported titanium catalyst Stereospecificity

Dynamic evolution of outer radiation belt electrons driven by superluminous R-X mode waves

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Science China(Technological Sciences) 2010年第10期53卷 2734-2738页

作者： XIAO FuLiang1,2. CHEN LiangXu1, HE YiHua1 & YANG Chang1 1 School of physics and Electronic Sciences, changsha {2. of Science and Technology, changsha 410004, China 2.State Key Laboratory of Space Weather, Chinese Academy of Sciences, Beijing 100190, China 1. School of physics and Electronic Sciences Changsha University of Science and Technology Changsha 410004 China2. State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China

We present initial results on the temporal evolution of the phase space density (PSD) of the outer radiation belt energetic electrons driven by the superluminous R-X mode waves. We calculate diffusion rates in pitch angle and momentum assuming the standard Gaussian distributions in both wave frequency and wave normal angle at the location L=6.5. We solve a 2. momentum-pitch-angle Fokker-Planck equation using those diffusion rates as inputs. Numerical results show that R-X mode can produce significant acceleration of relativistic electrons around geostationary orbit,supporting previous findings that superluminous waves potentially contribute to dramatic variation in the outer radiation belt electron dynamics.

关键词： wave-particle interaction superluminous R-X waves phase space density evolution radiation belt electrons

关于“滴状冷凝中液滴内外压强差及临界半径”的评注

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物理学报 2004年第5期53卷 1321-1324页

作者：曹治觉湖南师范大学理学院物理系

从力学和热力学角度简要证明了滴状冷凝时壁面球冠形液滴内外压强差不同于冷凝器内部球形液滴的内外压强差 ,并指出有关文献对壁面自由能增量的理解存在概念上的混乱。

关键词：滴状冷凝压差自由能力学热力学凝聚态物理临界半径

极化子效应对量子盘中线性和非线性光吸收系数的影响

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物理学报 2002年第9期51卷 2022-2028页

作者：刘翠红陈传誉马本堃北京师范大学物理系和理论物理研究所北京100875 广州大学理学院物理与电子信息系广州510405

利用密度矩阵的方法 ,得出了考虑极化子效应的量子盘的线性和非线性光吸收系数的解析表达式 ,并以GaAs为例讨论了光吸收系数与不同的入射光子能量和量子盘的厚度之间的关系 .结果表明。

关键词：量子盘极化子效应线性光吸收系数量子点非线性光吸收系数半导体非线性光学

New Exact and Explicit Solitary WaveSolutions to a Class of Coupled Nonlinear Equations

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Communications in Nonlinear Science and Numerical Simulation 1998年第3期3卷 189-193页

作者： Xuejun XU and Jiefang ZHANG(institute of Nonlinear physics and Dept. of physics. Zhejiang normal Univ., Jinhua32.004, China) institute of Nonlinear physics and D{2. of physics Zhejiang Normal University Jinhua 321004 China

New exact and explicit solitary wave solutions are obtained for the couplednonlinear equation by using a simple way of making the ansatz u(x, t) =Asechn ζ+A0with ζ = k(x+wt) +ζ0.

关键词： solitary wave solution ansatz coupled nonlinear equations