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Science China(Technological Sciences) 2010年第6期53卷 1534-1539页

作者： XIE ZiLing1,2,XIE JiJia2,HONG YouShi2 & WU XiaoLei2 1 College of Architecture and Civil Engineering,University of Wenzhou,Wenzhou 325035,China 2 State Key Laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China 1. College of Architecture and Civil Engineering University of Wenzhou Wenzhou 325035 China2. State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

Cu samples were subjected to high-pressure torsion (HPT) with up to 6 turns at room temperature (RT) and liquid nitrogen temperature (LNT),*** effects of temperature on grain refinement and microhardness variation were *** the samples after HPT processing at RT,the grain size reduced from 43 μm to 265 nm,and the Vickers microhardness increased from HV52 to ***,for the samples after HPT processing at LNT,the value of microhardness reached its maximum of HV150 near the center of the sample and it decreased to HV80 at the periphery *** observations revealed that HPT straining at LNT induced lamellar structures with thickness less than 100 nm appearing near the central region of the sample,but further deformation induced an inhomogeneous distribution of grain sizes,with submicrometer-sized grains embedded inside micrometer-sized *** submicrometer-sized grains with high dislocation density indicated their nonequilibrium *** the contrary,the micrometer-sized grains were nearly free of dislocation,without obvious deformation trace remaining in *** images demonstrated that the appearance of micrometer-sized grains is the result of abnormal grain growth of the deformed fine grains.

关键词： copper high pressure torsion (HPT) microstructure grain size microhardness cryogenic temperature

Effect of AlN intermediate layer on growing GaN film by hydride vapor phase epitaxy

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Rare Metals 2006年第z2期25卷 15-19页

作者： NOUET Gérard2 RUTERANA Pierre Laboratoire Structures des Interfaces et Fonctionnalité des Couches Minces UMR CNRS 6176 ENSICAEN6 Boulevard du Maréchal Juin 14050 Caen Cedex France

Thick GaN layer deposited by hydride vapor phase epitaxy (HVPE) on a metalorganic chemical vapor deposition (MOCVD) GaN template with a thin low temperature (LT) AlN intermediate layer was investigated. High resolution X-ray resolution diffraction (HRXRD) shows that the crystalline quality of thick GaN layer was improved compared with the template. As confirmed by atomic force microscopy (AFM) observations, the surface morphology of AlN intermediate layer helps to improve the nucleation of GaN epilayer. Photoluminescence (PL) spectra measurement shows its high optical quality and low compressive stress, and micro Raman measurement confirms the latter result. Thus, the deposition of the LT-AlN interlayer has promoted the growth of an HVPE-GaN layer with an excellent crystalline quality.

关键词： GaN AlN intermediate layer HVPE HRXRD AFM photoluminescence

Structure of the quaternary complex of histone H3-H4 heterodimer with chaperone ASF1 and the replicative helicase subunit MCM2

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Protein & Cell 2015年第9期6卷 693-697页

作者： Hong Wang (1) (2) Mingzhu Wang (1) Na Yang (1) (2) Rui-Ming Xu (1) (2) 1.National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China 2.University of Chinese Academy of Sciences Beijing 100049 China

The building block of eukaryotic chromatin is the nucleo- some core particle （NCP）, which is consisted of -146 bps of DNA wrapped around an octamer of core histones. A tetra- mer of histone H3 and H4 and two H2A-H2B dimers form the histone octamer （Kornberg, 1974; Luger et al., 1997; Tho- mas and Kornberg, 1975）. During DNA replication, nucleo- some disassembly and reassembly occurs at the replication fork, and histone chaperons CAF-1 and ASF1 are principally responsible for the deposition of histones H3 and H4 onto replicated DNA （Kaufman et al., 1995; Tyler et al., 1999）. ASF1 binds a heterodimeric histone H3-H4 complex through its conserved N-terminal domain （aa 1-155） and impedes the formation of the （H3-H4）2 tetramer both inside the nucleus and in the cytoplasm （English et al., 2005）.

关键词： Histone Chaperone Nucleosome Core Particle Quaternary Complex Replicative Helicase HeLa Cell Nuclear Extract

Mechanical Properties and Microstructure of Bionic Non-Smooth Stainless Steel Surface by Laser Multiple Processing

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Journal of Bionic Engineering 2009年第2期6卷 180-185页

作者： Jin-zhong Lu~(1,2) ,Chao-jun Yang~(1,2) ,Lei Zhang~(1,2),Ai-xin Feng ~(1,2) ,Yin-fang Jiang~(1,2)1.School of Mechanical Engineering,Jiangsu University,Zhenjiang 212013,P.R.China2.Jiangsu Provincial Key Laboratory for Science and Technology of Photon Manufacturing,Zhenjiang 212013,P.R.China [a]School of Mechanical Engineering Jiangsu University Zhenjiang 212013 P. R. China [b]Jiangsu Provincial Key Laboratory for Science and Technology of Photon Manufacturing Zhenjiang 212013 P. R. China

Laser multiple processing, i.e. laser surface texturing and then Laser Shock Processing (LSP), is a new surface processing technology for the preparation of bionic non-smooth surfaces. Based on engineering bionics, samples of bionic non-smooth surfaces of stainless steel 0Crl 8Ni9 were manufactured in the form of reseau structure by laser multiple processing. The mechanical properties (including microhardness, residual stress, surface roughness) and microstructure of the samples treated by laser multiple processing were compared with those of the samples without LSP The results show that the mechanical properties of these samples by laser multiple processing were clearly improved in comparison with those of the samples without LSP The mechanisms underlying the improved surface microhardness and surface residual stress were analyzed, and the relations between hardness, comnressive residual stress and roughness were also presented.

关键词： laser multiple processing laser surface texturing laser shock processing stainless steel 0Cr18Ni9 microhardness residual stress roughness

成都市人民政府成都警备区关于进一步鼓励大学生参军入伍的意见

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成都市人民政府公报

成都市人民政府公报 2024年第1期 22-24页

作者： 1.成都市人民政府 2.成都警备区成都市人民政府成都警备区

成府规〔2024〕3号各区（市）县政府（管委会）、人民武装部，市政府各部门，有关单位：为有效调动大学生青年应征入伍积极性，不断提高成都市兵员征集质量，推动全市征兵工作持续健康发展，根据《中华人民共和国兵役法》《征兵工作条...

成府规〔2024〕3号各区（市）县政府（管委会）、人民武装部，市政府各部门，有关单位：为有效调动大学生青年应征入伍积极性，不断提高成都市兵员征集质量，推动全市征兵工作持续健康发展，根据《中华人民共和国兵役法》《征兵工作条例》《退役士兵安置条例》《中共四川省委办公厅四川省人民政府办公厅四川省军区办公室印发〈关于进一步激励大学生和高原地区适龄青年应征入伍的工作措施〉的通知》（川委厅〔2021〕64号）有关规定，结合我市实际，现就进一步鼓励大学生参军入伍提出如下意见。

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Near infrared lights emission of ^(40)Ar^(16+) impacting on metal surfaces

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Science China(Physics,Mechanics & Astronomy) 2009年第7期52卷 1021-1026页

作者： ZHANG XiaoAn1,2, XIAO GuoQing2, YANG ZhiHu2, WANG Li1 & ZHAN WenLong2 1 Department of Physics, Xianyang Normal University, Xianyang 712000, China 2 Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China Department of Physics Xianyang Normal University Xianyang 712000 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

The highly charged ion 40Ar16+ with the velocity (kinetic energy EK=150 keV, velocity V=8.5×105 m/s) smaller than Bohr velocity (VBohr=2.9×106 m/s) was found to hove impacts on the surfaces of metals Ni, Mo, Au and Al, and the Ar atomic infrared light lines and X-rays spectra were simultaneously measured. The experimental results show that the highly charged ion that captures electrons is neutralized, and the multiply-excited hollow atom forms. The hollow atom cascade decay radiates lights from infrared to X-ray spectrum. The intensity of infrared lights shows that the metallic work functions play an important role in the neutralization process of highly charged ions during their interaction with metallic surfaces, which verifies the classical over-the-barrier model.

关键词： infrared light lines X-ray neutralization highly charged ions

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 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.

H_2 production with low CO selectivity from photocatalytic reforming of glucose on metal/TiO_2 catalysts

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Science China Chemistry 2008年第2期51卷 97-100页

作者： WU GuoPeng1,2, CHEN Tao2, ZHOU GuoHua 2, ZONG Xu2 & LI Can2 1 Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024, China 2 State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China Laboratory of Plasma Physical Chemistry Dalian University of TechnologyDalian 116024China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

H2 with low CO concentration is produced via photocatalytic reforming of glucose (as a representative of biomass component) on metal/TiO2 catalyst (metals: Pt, Rh, Ru, Ir, Au, Ni, Cu). It is shown that the loaded metals generally enhance the rate of H2 production, while they depress the CO selectivity. Both H2 production and CO selectivity are strongly dependent on the kind of deposited metals on TiO2. For example, Rh/TiO2 catalyst is found to be most active for H2 production while with the most extremely low CO concentration from the photocatalytic reforming of glucose.

关键词： photocatalysis H2 production CO selectivity glucose metal (Rh Pt Ru Ir Au Cu or Ni)/TiO2

Comparison of eastern paleo-Tethyan ophiolites and its geodynamic significance--Evidence from Dur'ngoi ophiolite

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Science China Earth Sciences 2004年第4期47卷 378-384页

作者： CHEN Liang1,2, SUN Yong1,2, PEI Xianzhi2, Feng Tao2 & Zhang Guowei2 1. Open Laboratory of Continental Dynamics, Ministry of Education, Northwest University, Xi抋n 710069, China 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China Open Laboratory of Continental Dynamics Ministry of Education Northwest University Xi’an 710069 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Nd-Pb isotopic geochemistry of metabasalt from Dur抧goi ophiolite, Qinghai Prov-ince, NW China reveals the presence of DMM mixing with EMII components in its upper mantle source, which is comparable with present Indian MORB. Comparisons indicate that the geo-chemistry, chronology and source characteristics of Dur抧goi ophiolite coincide with Pa-leo-tethyan ophiolites from 揝anjiang?area. Together with evidences from regional geology in adjacent areas, this study proves that independent paleo-tethyan basins evolved contemporarily, the dynamics of which is attributed to the interaction of mantle plume with over-riding lithosphere.

关键词： ophiolite, Paleo-Tethys, DUPAL anomaly, Indosinian movement.

Evaluation for Adhesion Strength of Coating and Substrateby Burying Beforehand Specimen

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Journal of Wuhan University of Technology(Materials Science) 2003年第1期18卷 31-32,36页

作者：廖义德 WuhanInstituteofChemicalTechnology

Adhesion strength is an important target in evaluating the quality of coating *** traditional way of adhesion strength test is bonding pull off method for thick layers and scratch test for thin *** drawbacks of these two methods are discussed in this paper,and an evaluating method for adhesion strength of coating by burying beforehand specimen is *** adhesion strength of samples is measured with two *** dispersity of testing data is lower than that in the ASTM C663 79 Standard.

关键词： coating adhesion strength specimen measure