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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 321000, china 3 institute 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 012000, china Huzhou Teachers College School of Science Huzhou China (GRID:grid.411440.4) (ISNI:***) Zhejiang Normal University School of Science and Information Engineering Jinhua China (GRID:grid.453534.0) (ISNI:***) Huzhou Teachers College School of Science Huzhou China (GRID:grid.411440.4) (ISNI:***) Zhejiang Normal University School of Science and Information Engineering Jinhua China (GRID:grid.453534.0) (ISNI:***) Chinese Academy of Sciences Institute of Theoretical Physics Beijing China (GRID:grid.9227.e) (ISNI:***) Huzhou Teachers College School of Science Huzhou China (GRID:grid.411440.4) (ISNI:***) Huzhou Teachers College School of Science Huzhou China (GRID:grid.411440.4) (ISNI:***) Zhejiang Normal University School of Science and Information Engineering Jinhua China (GRID:grid.453534.0) (ISNI:***) National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear Physics Lanzhou China (GRID:grid.450259.f) (ISNI:0000 0004 1804 2516) Huzhou Teachers College School of Science Huzhou China (GRID:grid.411440.4) (ISNI:***) Zhejiang Normal University School of Science and Information Engineering Jinhua China (GRID:grid.453534.0) (ISNI:***) Jining Teachers College Department of Physics Jining China (GRID:grid.452558.b)

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

Nonholonomic mapping theory of autoparallel motions in Riemann-Cartan space

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 1707-1715页

作者： GUO YongXin1,LIU Chang2,WANG Yong3,LIU ShiXing1 & CHANG Peng2 1 College of physics,Liaoning University,Shenyang 110036,china 2 School of Aerospace engineering,Beijing institute of Technology,Beijing 110081,china 3 School of Basic Medical Science,Guangdong Medical College,Dongguan 523808,china Liaoning University College of Physics Shenyang China (GRID:grid.411356.4) (ISNI:***) Beijing institute of Technology School of Aerospace Engineering Beijing China (GRID:grid.43555.32) (ISNI:***) Guangdong Medical College School of Basic Medical Science Dongguan China (GRID:grid.410560.6)

The method of nonholonomic mapping is utilized to construct a Riemann-Cartan space embedded into a known Riemann-Cartan space,which includes two special cases that a Weitzenbck space and a Riemann-Cartan space are respectively embedded into a Euclidean space and a Riemann *** means of this mapping theory,the nonholonomic corresponding relation between the autoparallels of two Riemman-Cartan spaces is *** particular,an autoparallel in a Riemann-Cartan space can be mapped into a geodesic line in a Riemann space and an autoparallel in Weitzenbck space be mapped into a geodesic line in Euclidean *** on the Lagrange-d'Alembert principle,the equations of motion for dynamical systems in Riemman-Cartan space should be autoparallel equations of the *** applications,the problem of autoparallel motion of spinless particles,Chaplygin's nonholonomic systems and a rigid body rotating with a fixed point are investigated in space with torsion.

关键词： nonholonomic mapping Riemann-Cartan space connection torsion autoparallel

Building damage in Dujiangyan during Wenchuan Earthquake

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Earthquake engineering and engineering Vibration 2008年第3期7卷 263-269页

作者： Zhang Minzheng and Jin Yingjie institute of engineering Mechanics, china Earthquake Administration, Harbin 150080, china Professor Graduate Student institute of engineering Mechanics China Earthquake Administration Harbin 150080 China

A field damage survey of 1,005 buildings damaged by the Wenchuan Earthquake in Dujiangyan City was carried out and the resulting data was analyzed using the statistical method. It is shown that buildings that were seismically designed achieved the desired seismic fortification target; they sustained less damage than the non-seismically designed buildings. Among the seismically designed buildings investigated, RC frame buildings performed the best in terms of seismic resistance. Masonry buildings with a ground story of RC frame structure were the second best, and masonry buildings performed the worst. Considering building height, multistory buildings sustained more severe damage than high-rise buildings and 2- and 3-story buildings. Compared to residential buildings, public buildings, such as schools and hospitals, suffered more severe damage.

关键词： Wenchuan Earthquake Dujiangyan building damage seismic intensity field survey

Correlation between Thermal Expansion and Magnetic Characteristics of Fe-Ni Alloys in Fe_(1-x)Ni_x/Cu Superlattices

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 169-174页

作者： Weizhong Tang H Zabel(Matrial Science and engineering School, University of Science and Technology Beijing, Beijing 100083, china)(institute of Experimental physics/Solid State physics, Ruhr University Bochum, 44780 Bochum, Germany) Material Science and engineering School University of Science and Technology Beijing Beijing 100083 China institute of Experimental physics/Solid State physics Ruhr University Bochum 44780 Bochum Germany

Thermal expansion behaviors of FeNi alloys were investigated by means of X-ray diffraction technique within a Fe1 -xNix/Cu superiattice structure. It was found that with a Ni concentration of x = 0.35, FeNi alloy layers showed the well-known Invar behavior, but for alloy layers with either lower or higher Ni concentrations, thermal expansion coefficients were larger. Based on results of magnetic measurements it is concluded that FeNi alloy layers with Ni concentrations lower than the Invar composition are in a superparamagnetic state which leads not only to low spontaneous magnetizations but also to large thermal expansions of the alloy layers.

关键词： thermal expansion Invar behavior FeNi alloys superlattice magnetism

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 102600, china 2. Department of Mechanics & engineering Science, Peking University, Beijing 100871, china Beijing institute of Graphic Communication Beijing China Department of Mechanics & engineering Science Peking University Beijing 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.

Gas kinetic algorithm for flows in Poiseuille-like microchannels using Boltzmann model equation

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 496-512页

作者： LI Zhihui1,2, ZHANG Hanxin1 & FU Song2 ⒈ National Laboratory for CFD, Hypervelocity Aerodynamics institute,china Aerodynamics Research and Development Center,Mianyang 621000,china 2.Department of engineering Mechanics,Tsinghua University,Beijing 100084,china National Laboratory for CFD Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development Center Mianyang China Department of engineering Mechanics Tsinghua University Beijing China

The gas-kinetic unified algorithm using Boltzmann model equation have been extended and developed to solve the micro-scale gas flows in Poiseuille-like micro-channels from Micro-Electro-Mechanical Systems (MEMS). The numerical modeling of the gas kinetic boundary conditions suitable for micro-scale gas flows is presented. To test the present method, the classical Couette flows with various Knudsen numbers, the gas flows from short microchannels like plane Poiseuille and the pressure-driven gas flows in two-dimensional short microchannels have been simulated and compared with the approximate solutions of the Boltzmann equation, the related DSMC results, the modified N-S solutions with slip-flow boundary theory, the gas-kinetic BGK-Burnett solutions and the experimental data. The comparisons show that the present gas-kinetic numerical algorithm using the mesoscopic Boltzmann simplified velocity distribution function equation can effectively simulate and reveal the gas flows in microchannels. The numerical experience indicates that this method may be a powerful tool in the numerical simulation of micro-scale gas flows from MEMS.

关键词： Boltzmann model equation, discrete velocity ordinate method, finite-difference scheme, Couette flow, Poiseuille flow, gas flow in short-microchannel.

Debating about the climate warming

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Progress in Natural Science:Materials International 2006年第1期16卷 1-6页

作者： WANG Shaowu1, LUO Yong2, ZHAO Zongci2, DONG Wenje2 and YANG Bao3 (1.Department of Atmospheric Sciences, School of physics, Peking University, Beijing 100871, china 2. Laboratory for Climate Studies, china Meteorological Administration, Beijing 100081, china 3. institute of Cold and Arid Regions Environmental and engineering, Chinese Academy of Sciences, Lanzhou 730000, china) Department of Atmospheric Sciences School of Physics Peking University Beijing 100871 China

Debating about the climate warming is reviewed. Discussions have focused on the validity of the temperature reconstruction for the last millennium made by Mann et al. Arguments against and for the reconstruction are introduced. Temperature reconstructions by other authors are examined, including the one carried out by Wang et al. in 1996. It is concluded that: (1) Ability of reproducing temperature variability of time scale less than 10 a is limited, so no sufficient evidence proves that the 1990s was the warmest decade, and 1998 was the warmest year over the last millennium. (2) All of the temperature reconstructions by different authors demonstrate the occurrence of the MWP (Medieval Warm Period) and LIA (Little Ice Age) in low frequency band of temperature variations, though the peak in the MWP and trough in LIA varies from one reconstruction to the others. Therefore, terms of MWP and LIA can be used in studies of climate change. (3) The warming from 1975 to 2000 was significant, but we do not know if it was the strongest for the last millennium, which needs to be proved by more evidence.

关键词： climate warming MWP LIA the 20th century.

GENERAL INTERPOLATION FORMULAS FOR SPACES OF DISCRETE FUNCTIONS WITH NONUNIFORM MESHES

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Journal of Computational Mathematics 1995年第1期13卷 70-93页

作者： Zhou Yu-lin(institute of Applied physics and Computational Mathematics, Beijing, china ) 北京应用物理和计算数学所北京

The unequal meshsteps are unavoidable in general for scientific and engineering computations especially in large Scale computations. The analysis of difference schemes with nonuniform meshes is very rare even by use of fully heuristic methods. For the purpose of the systematic and theoretical study of the finite difference method with nonuniform meshes for the problems of partial differential equations, the general interpolation formulas for the spaces of discrete functions of one index with unequal meshsteps are established in the present work. These formulas give the connected relationships among the norms of various types, such as' the sum of powers of discrete values, the discrete maximum modulo, the discrete Holder and Lipschitz coefficients.

关键词： Discrete functions Interpolation Mathematical constants Partial differential equations Difference quotients Real lines Finite difference methods Mathematical theorems Ratios engineering

Dynamic study of photosensitized one-electron oxidation of polyG by menadione

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Science china Chemistry 2005年第4期48卷 292-296页

作者： MA Jianhua1,LIN Weizhen2,DU Fuqiang2,HAN Zhenhui2,YAO Side2 & LIN Nianyun2 1.College of Biology engineering,Jimei University,Xiamen 361021,china 2.Laboratory of Nanobiomedicine & Laboratory of Radiation Chemistry,Shanghai institute of Applied physics,Chinese Acade Sciences,Shanghai 201800,china College of Biology engineering Jimei University Xiamen 361021 China

The electron transfer reaction of triplet menadione (3MQ?) with polyguanylic acid (polyG) in CH3CN rich (97%) solution was investigated by 248 nm(KrF) laser flash *** transient absorption spectra and kinetics obtained from the interaction of 3MQ? with polyG demonstrated that the primary radical ion pair,radical cation of polyG and radical anion of me-nadione can be detected *** results demonstrated that the reaction rate con-stant of 3MQ? with polyG is almost equal to that of 3MQ? with dGMP.

关键词： menadione, polyG, laser flash photolysis, triplet state, one electron oxidation.