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Suppression　of　Interference　Speckles　in　the　Uniform　Line　Focus　System　of　Segmented　Wedge　Array　Using　Phase－disturbed　Plate

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Chinese Journal of Lasers 1996年第4期B5卷 363-370页

作者： LIU Zhongyong ZHENG Ruilun(physics department of South-West Normal University,Chongqing630715,{2.)SUI Zhan(Laboratory for Laser Fusion,institute of nuclear physics and Chemistry ,{2. Academy of Engineering physics,Chendu 610003, china)LU Baida CAI South West Normal Univ Chongqing China

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关键词： phase-disturbed plate phase modulation time smoothing interference

atomic force microscopy studies of SrTiO_(3)(001)substrates treated by chemical etching and annealing in oxygen

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 459-468页

作者： WANG Xu1, FEI Yiyan1, LU Huibin1, JIN Kui-juan1, ZHU Xiangdong1,3, CHEN Zhenghao1, ZHOU Yueliang1 & YANG Guozhen1 1. beijing National Laboratory for Condensed Matter physics,{2. of physics,Chinese Academy of Sciences,beijing 100080,china 2. department of physics,University of California, Davis,California,USA 1. beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 2. department of physics University of California Davis California USA

The SrTiO3 (001) substrates treated by chemical etching in NH4F-buffered HF solution and annealing in oxygen ambient have been studied by an atomic force microscopy (AFM). The SrTiO3 substrates with TiO2.termineted and atomically smooth surfaces and single unit cell steps have been obtained. The surface morphologies of SrTiO3 substrates strongly depend on the treated conditions and the quality of the substrates.

关键词： SrTiO3, AFM, surface morphology, surface defects.

COMMENT ON WHETHER THE CONTACT TERM CONTRIBUTES TO DOUBLE CHARGE EXCHANGE REACTION

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中国科学院研究生院学报 1989年第2期6卷 48-51页

作者： Ma Weihsing (Center of Theoretical physics, CCAST (World Lab.), beijing) Yu Ziqiang ({2. of physics, Nankai University, Tianjin, china) He Hanxin (institute of atomic energy, Academia Sinica)

Based on the Olsson-Turn’s Lagrangian, contribution to DCX reaction from the contact term has been discussed, The result shows that althought there are some cancellations between the pole-and contact-term contributio... 详细信息

关键词： carefully contributions priori invariant Lagrangian 切二 nuclei Proceedings vertex Alamos

Density functional theory study on the structural and electronic properties of Ag-adsorbed (MgO)_n clusters

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Science china(physics,Mechanics & Astronomy) 2009年第5期52卷 734-741页

作者： GE GuiXian1, JING Qun1 & LUO YouHua2.3 1 Key Laboratory of Ecophysics and department of physics, Normal College, Shihezi University, Shihezi 832.03, china 2.School of Science, East china University of Science and Technology, Shanghai 2.02.7, china 3 institute for Theoretical physics, Henan University, Kaifeng 475004, china Key Laboratory of Ecophysics and department of physics Normal College Shihezi University Shihezi 832003 China School of Science East China University of Science and Technology Shanghai 200237 China institute for Theoretical physics Henan University Kaifeng 475004 China

Equilibrium geometries, charge distributions, stabilities and electronic properties of the Ag-adsorbed (MgO)n (n = 1-8) clusters have been investigated by density functional theory (DFT) with generalized gradient approximation (GGA) for exchange-correlation functional. The results show that hollow site is energetically preferred for n≥4, and the incoming Ag atoms tend to cluster on the existing Ag cluster. The Mulliken populations indicate that the interaction between the Ag atom and Magnesia clusters is mainly induced by a weak atomic polarization. The adsorbed Ag atom only causes charge redistributions of the atoms near itself. The effect of the adsorbed Ag atom on the bonding natures and structural features of Magnesia clusters is minor. Furthermore, the investigations on the first energy difference, fragmentation energies and electron affinities show that the Ag(MgO)4 and Ag(MgO)6 are the most stable among studied clusters.

关键词： Ag (MgO)_n clusters geometries electronic properties

Study of the primordial lithium abundance

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 67-72页

作者： LI ZhiHong1, LI ErTao1, SU Jun1, LI YunJu1, BAI XiXiang1, GUO Bing1, WANG YouBao1, CHEN YongShou1, HOU SuQing1, ZENG Sheng1, LIAN Gang1, SHI JianRong2.& LIU WeiPing1 1 china institute of atomic energy, beijing 102413,{2. 2.ational Astronomical Observatories, Chinese Academy of Sciences, beijing 100012.{2. china Inst Atom energy Beijing 102413 Peoples R China Chinese Acad Sci Natl Astron Observ Beijing 100012 Peoples R China

Lithium isotopes have attracted an intense interest because the abundance of both 6Li and 6Li from big bang nucleosynthesis (BBN) is one of the puzzles in nuclear astrophysics. Many investigations of both astrophysical observation and nucleosynthesis calculation have been carried out to solve the puzzle, but it is not solved yet. Several nuclear reactions involving lithium have been indirectly measured at china institute of atomic energy, beijing. The Standard BBN (SBBN) network calculations are then performed to investigate the primordial Lithium abundance. The result shows that these nuclear reactions have minimal effect on the SBBN abundances of 6Li and 7Li.

关键词： big bang nucleosynthesis element abundance nuclear reaction network

Ab initio study of a Y-doped Σ31 grain boundary in alumina

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Science china(physics,Mechanics & Astronomy) 2008年第11期51卷 1607-1615页

作者： CHEN Jun, XU Yun, CHEN DongQuan & ZHANG JingLin Laboratory of Computational physics, institute of Applied physics and Computational Mathematics, beijing 100088, china 1. Laboratory of Computational physics Institute of Applied Physics and Computational Mathematics Beijing 100088 China

The atomic structures and energetics of clean and Y-doped general grain boundary (GB) Σ31/(0001) models in α-Al2.3 are studied by a series of high precision ab initio calculations. A large supercell with 700 atoms and periodic boundary conditions is adopted for undoped and Y-doped GB with different substitution sites and con-centrations. It is shown that Y atoms preferably segregate to the central column of the 7-member Al ring. This is explained as more favorable bond formation for Y in this position and lower GB energy. The calculated GB formation energy for the clean and Y-doped cases is respectively 3.99 and 3.67 J/m2. On the average, the GB region in Σ31 has a slightly lower charge density than the bulk crystalline region. In addtition, the GB induces a long ranged asymmetric electrostatic potential distri-bution on each side of the grain boundary.

关键词： alumina grain boundary Y-doped ab initio

Calculation and Evaluation of the Activation Cross Sections for 187Re(n,2.)186m,gRe Reactions

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中国核科技报告 1998年第S2期 146-150页

作者： Huang Xiaolong Lu Hanlin Zhou Chunmei (china institute of {2. energy, beijing 102413)

The activation cross sections forRe(n,2.)Re reactions are calculated using UNF code. The calculations are in good agreement with the re-evaluated measured data. Finally the excitation function forRe(n,2.)Re reactions ... 详细信息

关键词： Calculation and Evaluation of the Activation Cross Sections for Re n,2. g)Re Reactions

Experiments and sensitivity analyses for heat transfer in a meter-scale regularly fractured granite model with water flow

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Journal of Zhejiang University-Science A(Applied physics & Engineering) 2012年第12期13卷 958-968页

作者： Wei LU1,2.Yan-yong XIANG1 (1School of Civil Engineering,beijing Jiaotong University,beijing 100044,{2.) (2.tate Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,{2. institute of Water Resources and Hydropower Research,beijing 100038,{2.) 1. School of Civil Engineering Beijing Jiaotong University Beijing 100044 China 2. State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research Beijing 100038 China

Experiments of saturated water flow and heat transfer were conducted for a meter-scale model of regularly fractured granite. The fractured rock model （height 1502.5 ram, width 904 mm, and thickness 300 mm）, embedded with two vertical and two horizontal fractures of pre-set apertures, was constructed using 18 pieces of intact granite. The granite was taken from a site currently being investigated for a high-level nuclear waste repository in china. The experiments involved different heat source temperatures and vertical water fluxes in the embedded fractures either open or filled with sand. A finite difference scheme and computer code for calculation of water flow and heat transfer in regularly fractured rocks was developed, verified against both the experimental data and calculations from the TOUGH2.code, and employed for parametric sensitivity analyses. The experiments revealed that, among other things, the temperature distribution was influenced by water flow in the fractures, especially the water flow in the vertical fracture adjacent to the heat source, and that the heat conduction between the neighboring rock blocks in the model with sand-filled fractures was enhanced by the sand, with larger range of influence of the heat source and longer time for approaching asymptotic steady-state than those of the model with open fractures. The temperatures from the experiments were in general slightly smaller than those from the numerical calculations, probably due to the fact that a certain amount of outward heat transfer at the model perimeter was unavoidable in the experiments. The parametric sensitivity analyses indicated that the tem- perature distribution was highly sensitive to water flow in the fractures, and the water temperature in the vertical fracture adjacent to the heat source was rather insensitive to water flow in other fractures.

关键词： Fractured granite Water flow Heat transfer Physical modeling Numerical calculation Sensitivity analysis

EXAFS Studies on Local atomic Structure in the Amorphous Mg_(65)Cu_(2.)Gd_(10) Alloy

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Journal of Wuhan University of Technology(Materials Science) 2011年第1期26卷 98-101页

作者：李国强 Business Development department China Perfect Machinery Industry Corp. Ltd

Local atomic structures of an amorphous Mg65Cu2.Gd10 alloy and the structural changes by thermal annealing have been studied by extended X-ray absorption fine structure （EXAFS）. The correlation between structural changes and mechanical properties for the Mg65Cu2.Gd10 alloy has also been discussed. Results showed that Cu atoms around Gd in Mg65Cu2.Gd10 lost rapidly during annealing , resulting in the segregation of Cu atoms. The coordination number NGd-Mg of Mg65Cu2.Gd10 annealed at 373 K first diminished and then augmented with the increase of annealing time. The formation of polyhedral short-range order unit with coordination number of nearly 12.around Gd atoms is in favor of the improvement of mechanical properties. The chemical short-range order, not topological short-range order in the amorphous Mg65Cu2.Gd10 alloy had obvious changes during annealing.

关键词： magnesium alloy amorphous alloy short-range EXAFS mechanical properties annealing