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The refined theory of deep rectangular beams for symmetrical deformation

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Science china(physics,Mechanics & Astronomy) 2009年第6期52卷 919-925页

作者： GAO Yang1 & WANG MinZhong2 1 college of Science, china Agricultural university, Beijing 100083. china 2 State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Aerospace engineering, Peking university, Beijing 100871, china college of Science China Agricultural University Beijing China State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Aerospace engineering Peking University Beijing China

Based on elasticity theory, various one-dimensional equations for symmetrical deformation have been deduced systematically and directly from the two-dimensional theory of deep rectangular beams by using the Papkovich-Neuber solution and the Lur'e method without ad hoc assumptions, and they construct the refined theory of beams for symmetrical deformation. It is shown that the displacements and stresses of the beam can be represented by the transverse normal strain and displacement of the mid-plane. In the case of homogeneous boundary conditions, the exact solutions for the beam are derived, and the exact equations consist of two governing differential equations: the second-order equation and the transcendental equation. In the case of non-homogeneous boundary conditions, the approximate governing differential equations and solutions for the beam under normal loadings only and shear loadings only are derived directly from the refined beam theory, respectively, and the correctness of the stress assumptions in classic extension or compression problems is revised. Meanwhile, as an example, explicit expressions of analytical solutions are obtained for beams subjected to an exponentially distributed load along the length of beams.

关键词： deep rectangular beams the refined theory symmetrical deformation the Papkovich-Neuber solution the Lur’e method

Study on Thermodynamic Properties of Lithium by First-principles and Quasi-harmonic Debye Model

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Semiconductor Photonics and Technology 2010年第4期16卷 141-145页

作者： LEI Jiehong1,3. DUAN Hao2, XING Pifeng3. TANG Yongjian3.(1. physics and Electronic Information Institute, china West normal {3., Nanchong 63.002, CHN 2. Chemistry and Chemical engineering college, Mianyang normal {3., Mianyang 621000, CHN 3. Research Center of Laser Fusion, china Academy of Engingeering physics, Mianyang 621900, CHN) physics and Electronic Information Institute China West Normal University Nanchong 637002 Chemistry and Chemical engineering college Mianyang Normal University Mianyang 621000 Research Center of Laser Fusion China Academy of Engingeering Physics Mianyang 621900

In this paper, the lattice parameter and bulk modulus of lithium(Li) at different pressures and temperatures are calculated by using the density functional theory method within the generalized gradient approximation(GGA).Through the quasi-harmonic Debye model, the thermodynamic properties of Li are predicted. The dependences of the normalized primitive cell volume V/V0 on pressure P, the variation of the thermal expansion coefficient α with pressure P and temperature T, as well as the dependences of the heat capacity Cv on pressure P and temperature T are obtained systematically in the ranges of 0~100 GPa and 0~2 000 K.

关键词： density functional theory the quasi-harmonic Debye model thermodynamic properties

Elastic differential cross sections of electron scattering by CF4 at intermediate energies

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原子与分子物理学报 2000年第1期17卷 82-85页

作者： JIANG Yu hai 1,LI Ji ming 2,SUN Jin feng 1,WAN Ling de 1 (1, Department of physics, college of physics and Information {3., Henan normal university, Xinxiang, Henan 453.02 2, Department of physics, Henan college of Education, Zhengzhou Henan 45003. 河南师范大学河南新乡 4530 0 2 河南教育学院河南郑州 45003

1　ＩＮＴＲＯＤＵＣＴＩＯＮＣａｒｂｏｎｔｅｔｒａｆｌｕｏｒｉｄｅ(ＣＦ4)ｉｓｏｎｅｏｆｔｈｅｍｏｓｔｗｉｄｅｌｙｕｓｅｄｃｏｍｐｏｎｅｎｔｓｏｆｆｅｅｄｇａｓｍｉｘｔｕｒｅｓｅｍｐｌｏｙｅｄｆｏｒａｖａｒｉｅｔｙｏｆ... 详细信息

1　ＩＮＴＲＯＤＵＣＴＩＯＮＣａｒｂｏｎｔｅｔｒａｆｌｕｏｒｉｄｅ(ＣＦ4)ｉｓｏｎｅｏｆｔｈｅｍｏｓｔｗｉｄｅｌｙｕｓｅｄｃｏｍｐｏｎｅｎｔｓｏｆｆｅｅｄｇａｓｍｉｘｔｕｒｅｓｅｍｐｌｏｙｅｄｆｏｒａｖａｒｉｅｔｙｏｆｐｌａｓｍａａｓｓｉｓｔｅｄｍａｔ...

关键词： elastic differential cross sections CF 4 independent atom model

Theoretical study of the interaction mechanism of single-electron halogen bond complexes H_3.…Br-Y(Y=H,CN,NC,CCH,C_2H_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,{3. 2Lanzhou Institute of Chemical physics,Chinese Academy of Sciences,Lanzhou 73.000,{3. college of Life Science and Chemistry Tianshui Normal University Tianshui China Lanzhou Institute of Chemical physics Chinese Academy of Sciences Lanzhou China

The characteristics and structures of single-electron halogen bond complexes H3.…Br-Y(Y = H,CCH,CN,NC,C2H3. have been investigated by theoretical calculation *** geometries were optimized and frequencies calculated at the B3.YP/6-3.1++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 MP2/6-3.1++G *** each H3.…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

OSCILLATION THEOREMS FOR SECOND ORDER FORCED NONLINEAR DIFFERENTIAL EQUATIONS WITH DELAYED ARGUMENT

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Annals of Differential Equations 2010年第3期26卷 368-372页

作者： Junhua Zhao (Dept. of Math., qufu normal university, qufu 273.65, Shandong) Xiao Nie (Dept. of Math., Dingtao Primary School, Qingdao 266602, Shandong) Xiaojuan Sun (college of Water Resources and Architectural {3., Tarim university, 843.00, Xinjiang)

By a Riccati transformation, we establish some new oscillation criteria which im-prove and generalize some known results in the previous literatures.

关键词： oscillation forced nonlinear differential equations delayed argument

非定常不可压N-S方程的一种有效预处理数值方法

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水动力学研究与进展（A辑） 2002年第6期17卷 729-738页

作者：薛具奎西北师范大学物理与电子工程学院甘肃兰州730070

本文发展了一非定常不可压流的有效预处理求解方法。应用预处理技术 ,对不可压N S方程使用双时间推进法求解。当沿物理时间层推进时 ,连续性方程和动量方程沿伪时间方向迭代求解。在沿伪时间方向迭代时 ,设计了一简化的有效标量隐式线 (... 详细信息

本文发展了一非定常不可压流的有效预处理求解方法。应用预处理技术 ,对不可压N S方程使用双时间推进法求解。当沿物理时间层推进时 ,连续性方程和动量方程沿伪时间方向迭代求解。在沿伪时间方向迭代时 ,设计了一简化的有效标量隐式线 (Gauss Sidel)迭代算法。对流项采用三阶迎风差分法离散 ,同时对数值通量项进行了预处理。数值分析了预处理对数值解精度和收敛性的影响。对振荡平板的非定常流动及不同Re数下定常、非定常驱动方腔流动的数值模拟结果表明 ,本文发展的非定常不可压流的预处理求解方法 ,不但提高了计算效率 ,而且减小了人工粘性 ,改善了数值解的精度。

关键词：非定常不可压 N-S方程预处理数值模拟

The Discharge Characteristics of Zinc-air Batteries by Laying Styles of Air Electrodes

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The Discharge Characteristics of Zinc-air Batteries by Layin...

Quantum Chemistry Study on Dissociation of Oxalyl Bromide

渗流力学与工程的创新与实践——第十一届全国渗流力学学术大会

作者： Song Fuquan (1 college of Mathematics,physics and Information engineering, Zhejiang {3. university,Jinhua Zhejiang 3.1004,china)

The effects of laying styles of air electrode on discharge performance of zinc-air batteries are studied by some *** discharge experiments of same zinc-air batteries with same air electrodes and different laying styles are researched,and the discharge characteristics and the mechanism of chemical reaction on electrode surface are analyzed. The experiments show that the reaction area is the part of air-electrode which opening to air,and the part which submerged in liquid doesn’t react;the discharge power of zinc-air battery increases with the area growth which opening to air,the relation between the discharge power of zinc-air battery and the air electrode reaction area is the linear relations,but is not the simple direct ratio *** experiments data also indicate that the discharge efficiency of electrode part near the water line is far more than other parts,which is about more than 80%of the total power of the air-zinc battery,and the reason is because that the section has a very short distance to the electrolyte and then the oxygen molecules easily gain *** results of the experiments are useful to devise air-electrodes and air-zinc batteries.

关键词： zinc-air battery air electrode laying style discharge efficiency

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Chinese Journal of Structural Chemistry 2005年第11期 116-121+12页

作者： GENG Zhi-Yuana② WANG Dong-Meia, c WANG Yong-Chenga DAI Guo-Lianga LU Ling-Linga WANG Han-Qingb a (college of Chemistry and Chemical engineering, Northwest normal {3., Lanzhou 73.070, china) b (Lanzhou Institute of Chemistry and physics, The Chinese Academy of Sciences, Lanzhou 73.000, china) c (Department of Chemistry, Baoji college of Arts & Sci., Baoji 721007, china) college of Chemistry and Chemical engineering， Northwest normal {3.， Lanzhou 73.070， china college of Chemistry and Chemical engineering， Northwest normal {3.， Lanzhou 73.070， china Department of Chemistry， Baoji college of Arts & Sci.， Baoji 721007，china Lanzhou Institute of Chemistry and physics，The Chinese Academy of Sciences， Lanzhou 73.000， china

The multi-bond dissociation dynamics of oxalyl bromide ((BrCO)2) has been in- vestigated by DFT and CIS calculations. Upon the results, conclusion could be drawn that disso- ciation of C–Br bond of oxalyl bromide at the ground state (S0) is of barrierless. After the absorption of a photon, (BrCO)2 is excited to the first excited state and one of its C–Br bonds is broken to yield Br˙* and BrCOCO˙* free radicals. In addition, BrCOCO˙* with high energy is apt to release en- ergy, and ultimately, turns into BrCOCO˙of the ground state. The energy is adequate for BrCOCO˙to break down into Br˙and 2CO; at the same time the C–C and C–Br bonds of BrCOCO˙free radicals dissociate.

关键词： oxalyl bromide multi-bond dissociation BrCOCO˙free radical DFT

Prediction of Earthquake in Yunnan Region Based on the AHC over Sampling

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Prediction of Earthquake in Yunnan Region Based on the AHC o...