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Theoretical study of ZnO adsorption and bonding on Al_2O_3.0001) surface

Science china(physics,Mechanics & Astronomy) 2004年第6期47卷 664-675页

作者： LI Yanrong1,YANG Chun1,2,XUE Weidong1,LI Jinshan3.& LIU Yonghua3.1.institute of Microelectronics and Solid State Electronics,University of Electronic Science and Technol- ogy of china,Chengdu 610054,china 2.institute of Mathematics and Software Science,Sichuan Normal University,Chengdu 610068,china 3.institute of Chemical materials,china academy of engineering physics,mianyang 621000,china institute of Microelectronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China institute of Mathematics and Software Science Sichuan Normal University Chengdu 610068 China institute of Chemical materials China Academy of Engineering Physics Mianyang 621000 China

ZnO adsorption on sapphire (0001) surface is theoretically calculated by using a plane wave ultrasoft pseudo-potential method based on ab initio molecular dynamics. The results reveal that the surface relaxation in the first layer Al-O is reduced, even eliminated after the surface adsorption of ZnO, and the chemical bonding energy is 43..3.±3..6) kJ·mol?1. The chemical bond of ZnO (0.185 ± 0.01 nm) has a 3.° angle away from the adjacent Al-O bond, and the stable chemical adsorption position of the Zn is deflected from the surface O-hexagonal symmetry with an angle of about 3.°. The analysis of the atomic populations, density of state and bonding electronic density before and after the adsorption indicates that the chemical bond formed by the O2 of the ZnO ? and the surface Al3. has a strong ionic bonding characteristic, while the chemical bond formed by the Zn2+ and the surface O2 has an obvious covalent characteristic, which ? comes mainly from the hybridization of the Zn 4s and the O 2p and partially from that of the Zn 3. and the O 2p.

关键词： α-Al2O3.(0001) ZnO ab initio molecular dynamics chemical adsorption density of states

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Ab initio Calculation of Intermolecular Dispersion Energy and Induction Energy of Nitramide Dimer

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Chinese Journal of Chemistry 2004年第11期22卷 1377-1381页

作者：宋华杰肖鹤鸣董海山institute of Chemical materials china academy of engineering physics {3. Sichuan 621900 china 黄奕刚institute of Chemical materials china academy of engineering physics {3. Sichuan 621900 china 龙新平institute of Chemical materials china academy of engineering physics {3. Sichuan 621900 china 汤业鹏institute of Chemical materials china academy of engineering physics {3. Sichuan 621900 china Department of Chemistry Nanjing University of Science and Technology Nanjing Jiangsu 210094 China institute of Chemical materials China Academy of Engineering Physics Mianyang Sichuan 621900 China

The dispersion energies, induction energies and their exchange counterparts (exchange-dispersion and ex-change-induction energies) between two interacting nitramide molecules at several separations are derived based upon symmetry-adapted perturbation theory (SAPT). The results show that (1) the effect of intramonomer electron correlation on dispersion energies and induction energies for nitramide dimer system is remarkable especially in the region near the van der Waals minimum distance (0.42 nm). (2) At smaller separations the dispersion energies and the induction energies are largely quenched by their exchange counterparts, and this case in induction interaction is much more remarkable than in dispersion interaction. (3. Since at shorter distances there exists the strong short-range interaction due to electron transfer which quickly decays and even disappears at larger separations, the two different R-dependency formulae of induction energies were found: one is ca. R-12.7 at short distances, and the other ca. R-7.0 at large separations. The latter R-dependency is similar to that (ca. R-7.2) of dispersion. (4) In the case of strong polar interaction existing in nitramide dimer, the true induction correlation terms of higher order than t(22)indE may be important.

关键词： dispersion energy induction energy nitramide dimer symmetry-adapted perturbation theory

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Trace tritium recovery from the residue of liquid Li_(17)Pb_(83. alloy

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Science china Chemistry 2010年第8期53卷 1825-1828页

作者： XIE Bo,YANG TongZai & WENG KuiPing institute of Nuclear physics and Chemistry,china academy of engineering physics,{3. 621900,china institute of Nuclear physics and Chemistry China Academy of Engineering Physics Mianyang China

The liquid Li17Pb83.alloy is a prominent breeder material for use in a fusion *** the design of an effective tritium extraction system for the liquid lithium lead bubbler of the test blanket module of such a reactor,finding ways to strictly limit the losses of tritium and to minimize radioactive risks is very *** this purpose,the isotope exchange process has been investigated as a means of trace tritium recovery from a model of the residue from Li17Pb83.*** results indicate that the isotope exchange process is an effective means of tritium recovery from the residue of Li17Pb83.alloy,and the optimum composition of the exchange carrier gas is He + 0.1% *** exchange temperature and number of exchange steps are the main factors influencing the efficiency of tritium recovery from the *** tritium recovery efficiency increases with increasing exchange temperature and number of times of *** recovery efficiency can approach 80% when the residue is treated six times at 823.K.A gas-liquid two-phase contact model to describe the proceeding of tritium release from the liquid Li17Pb83.alloy has been derived on the basis of this experiment.

关键词： Li17Pb83 alloy tritium recovery isotope exchange carrier

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Electronic structure and magnetism of R(Fe,Si)_(12) (R=Y,Nd)

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2, FAN Zhijian1, GAO Tao3.& QI Xinhua3.. institute of Nuclear physics and Chemistry, china academy of engineering physics, {3. 621900, china 2. Department of physics, Peking university, Beijing 100871, china 3. institute of Atomic and Molecular physics, Sichuan University, Chengdu 610065, china institute of Nuclear physics and Chemistry China Academy of Engineering Physics Mianyang China Department of physics Peking university Beijing China institute of Atomic and Molecular physics Sichuan University Chengdu China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12 compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2 (R = Y, Nd) are larger than those of RFe10M2 (M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12(R = Y Nd) magnetic moment Density of state.

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Inhibit the Porosity with Electron Beam Scanning Method in Welding LD10 Aluminum Alloy

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稀有金属材料与工程 2011年第S4期40卷 54-57页

作者： Mo Zhonghai,Wang Yarong,Huang Wenrong institute of Machinery Manufacturing Technology,china academy of engineering physics,mianyang 621900,{3. china Acad Engn Phys Inst Machinery Mfg Technol Mianyang 621900 Peoples R China

LD10 aluminum alloy is becoming widely used in aeronautics and astronautics industries for the advantages of high specific strength and good mechanical *** alloy is an active metal with low melting point and boiling *** porosity is apt to occur in the processing of electron beam *** this article,the author investigated the influence of electron beam scanning welding parameters (scanning figure,scanning frequency,focus,and welding speed) on porosity.10 mm thick LD10 aluminum alloy were welded and then tested by X-ray *** experiment results indicated that rational parameters would reduce the occurrence opportunity of *** the parameters of circle scanning,high scanning frequency,focus-out,and smaller welding speed,the porosity can be significantly reduced.

关键词： electron beam welding LD10 aluminum alloy porosity

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An Absolute Method for Determination ofThermal Conductivities of Thermal Insulators by Microcalorimetry

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Journal of Thermal Science 1996年第2期5卷 93-98页

作者： Chen Xuelin(institute of Chemical materials, china academy of engineering physics,Chengdu 610003. {3.) institute of Chemical materials China Academy of Engineering Physics Chengdu China

Microcalorimetry was developed to determine thermal conductivities (λ) of thermal insulators with hollow cylindrical shapes. A special device of specimen with resistance threads wrapped on its surface and electric heater placed in its hole was designed to meet the needs of determiningλ without using standard substances to calibrate the instrument. A formula for calculating the value of λ was *** heating in the hole and on the surface of the specimen respectively, the values of λ can be obtained conveniently by this technique. The method was tested with teflon, plexiglass, quartz glass and polyethylene. The experimental values of λ for the four substances agree well with the literatures *** analysis was also made on the experimental data. It was found that the main factors affecting values of λ are: (1) The errors of determining the values of heat cumulated in specimen and materials in the space around it and (2) the errors of determining the values of inner and outer radii of cylindrical specimen.

关键词： thermal conductivity absolute method compensation microcalorimetry

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Processing technique of target capsule's micro inflation hole with a scanning probe

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Science china(Technological Sciences) 2004年第1期47卷 77-84页

作者： SUN Tao, YAN Yongda, GAO Dangzhong, TANG Yongjian, FU Yibei & DONG ShenPrecision engineering Research institute, Harbin institute of Technology, Harbin 150001, {3. Research Centre of Laser Fusion, Chinese academy of engineering Plysics, mianyang 621900, {3. institute of Nuclear physics and Chemistry, Chinese academy of engineering physics, mianyang 621900, {3. Precision engineering Research institute Harbin Institute of Technology Harbin China Research Centre of Laser Fusion Chinese Academy of Engineering Plysics Mianyang China institute of Nuclear physics and Chemistry Chinese Academy of Engineering Physics Mianyang China

To resolve inflation of inertial confinement fusion (ICF) target and encapsulation of micro inflation hole with adhesive, a scanning probe microscope (SPM) diamond microprobe was used as the cutting tool with SPM in contact mode. Some parameters influencing the quality of micro inflation hole, such as the scanning direction of the diamond tip, the scanning rate and the contact force are discussed. Accurate taper hole was achieved whose climension and precision could meet the requirements of inflation and encapsulation technique of micro hole. The experimental results show that using SPM diamond microprobe as the cutting tool and with special processing technique, the precision machining of target capsule's taper inflation hole can be realized. A novel operative technology for filling high Z gas to target is provided.

关键词： target capsule, scanning probe microscope (SPM), diamond microprobe, processing technique, brittle material.

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Molecular dynamics simulations on the structures and properties of ε-CL-20-based PBXs ——Primary theoretical studies on HEDM formulation design

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Science china Chemistry 2007年第6期50卷 737-745页

作者： XU XiaoJuan1,2, XIAO JiJun1, HUANG Hui3. LI JinShan3.& XIAO HeMing1 1 Department of Chemistry, Nanjing University of Science and Technology, Nanjing 210094, china 2 Department of Chemistry, Yancheng Teacher’s College, Yancheng 224002, china 3.institute of Chemical {3., china academy of engineering physics, mianyang 621900, china Department of Chemistry Nanjing University of Science and Technology Nanjing China Department of Chemistry Yancheng Teacher’s College Yancheng China institute of Chemical materials China Academy of Engineering Physics Mianyang China

Five polymer bonded explosives(PBXs)with the base explosive epsilon-CL-20(hexanitrohexaazaisowurtzi-tane),the most important high energy density compound(HEDC),and five polymer binders(Estane 5703.GAP,HTPB,PEG,and F_(23.4))were *** dynamics(MD)method was employed to investigate their binding energies(E_(bind))3.≈ epsilon-CL-20/GAP 3.4).By pair correlation function g(r)analyses,hydrogen bonds and vdw are found to be the main interactions between the two *** elasticity and isotropy of PBXs based epsilon-CL-20 can be obviously improved more than pure epsilon-CL-20 *** is not by changing the molecular structures of epsilon-CL-20 for each binder to affect the *** safety and energetic properties of these PBXs are mainly influenced by the thermal capability(C_p^(deg))and density(p)of binders,respectively.

关键词： high energy density material (HEDM), hexanitrohexaazaisowurtzitane (CL-20), polymer bonded explosives (PBXs), molecular dynamics (MD), compatibility, safety properties, mechanical properties, energetic properties

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Light A physics in the lepton-specific two-Higgs doublet model

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 1981-1987页

作者： CAO JunJie 1,HENG ZhaoXia 2,3.& WAN PeiHua 1 1 College of physics & Information engineering,Henan Normal University,Xinxiang 453.07,china 2 Key Laboratory of Frontiers in Theoretical physics,institute of Theoretical physics,Chinese academy of Sciences,Beijing 100190,china 3.Kavli institute for Theoretical physics china,Chinese academy of Sciences,Beijing 100190,china College of physics & Information engineering Henan Normal University Xinxiang China Key Laboratory of Frontiers in Theoretical physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing China Kavli institute for Theoretical physics china Chinese Academy of Sciences Beijing China

We examine various direct and indirect constraints on the lepton-specific two-Higgs doublet model and discuss its phenomenology at colliders in the allowed parameter *** constraints we consider come from the precision electroweak data,the direct search for Higgs boson,the muon anomalous magnetic moment,as well as some theoretical consistency *** find that in the allowed parameter space the CP-odd Higgs boson A is rather light (m A 3. GeV with 95% possibility),which is composed dominantly by the leptonic Higgs and decays dominantly into τ + τ;while the SM-like Higgs boson h (responsible largely for electroweak symmetry breaking) decays dominantly in the mode h → AA → 4τ with a large decay width,which will make the Higgs discovery more difficult at the ***,this scenario predicts rare Z decays Z → AAA and Z →τ + τA with their branching ratios ranging from 10-8 to 10-and 10-5 to 10-4 respectively,which may be accessible at the GigaZ option of the ILC.

关键词： Lepton-specific two-Higgs doublt model light Higgs boson A Z decays

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Radiation Effect of Neutrons in a Reactor on Polyurethane

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Journal of Wuhan University of Technology(materials Science) 2010年第6期25卷 966-968页

作者：黄玮 institute of Nuclear physics and Chemistry China Academy of Engineering Physics

The radiation effect of neutrons in a reactor on polyurethane was *** gases produced by irradiated samples were analyzed by gas chromatography,and the dynamic mechanical and compression properties of the samples were also *** positron annihilation lifetime of irradiated samples was measured at room temperature in *** experimental results indicate that gas chromatography is a powerful tool to quantitatively analyze the gas products from neutron-irradiated polyurethane and characterizes the chemical changes in the *** the changes in microstructure determined from the PAL correlate well with the measurements of the mechanical properties by dynamic mechanical analysis（DMA）.

关键词： neutrons in a reactor polyurethane radiation effect

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