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

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 {2. china academy of engineering physics mianyang Sichuan 62.900 china 黄奕刚institute of chemical {2. china academy of engineering physics mianyang Sichuan 62.900 china 龙新平institute of chemical {2. china academy of engineering physics mianyang Sichuan 62.900 china 汤业鹏institute of chemical {2. china academy of engineering physics mianyang Sichuan 62.900 china Department of Chemistry Nanjing University of Science and Technology Nanjing Jiangsu 210094 China institute of chemical {2. 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(2.)indE may be important.

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

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引用

Science china Chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1,2. XIAO Heming1 & DONG Haishan2.1. Department of Chemistry, Nanjing University of Science and Technology, Nanjing 2.0094, china 2. institute of chemical materials,{2., mianyang 62.900, china 1. Department of Chemistry Nanjing University of Science and Technology 210094 Nanjing China 2. institute of chemical materials China Academy of Engineering Physics 621900 Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2. HF2.and (N2.2.and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

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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 {2., china academy of engineering physics,Chengdu 610003, china) institute of chemical {2. 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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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,{2. academy of engineering physics,mianyang 62.900,{2. 1. institute of Nuclear physics and Chemistry China Academy of Engineering Physics Mianyang 621900 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 82. 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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Theoretical study of ZnO adsorption and bonding on Al_2._3(0001) surface

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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,{2. 2.institute of Mathematics and Software Science,Sichuan Normal University,Chengdu 610068,{2. 3.institute of chemical materials,{2. academy of engineering physics,{12. 62.000,{2. 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 {2. 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 434.3(±38.6) kJ·mol?1. The chemical bond of ZnO (0.185 ± 0.01 nm) has a 30° 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 30°. 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 2. and partially from that of the Zn 3d and the O 2..

关键词： α-Al2.3 (0001) ZnO ab initio molecular dynamics chemical adsorption density of states

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Encapsulation of inorganic particles by dispersion polymerization through ultrasonic irradiation

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Science china Chemistry 2005年第6期48卷 545-552页

作者： ZHANG Kai1,2. FU Qiang1, HUANG Yuhong2.& ZHOU Dehui2.1. College of Polymer Science and engineering, Sichuan University, Chengdu 610065, china 2. {2. of Structure Mechanics, china academy of engineering physics, mianyang 62.900, china 1. College of Polymer Science and engineering Sichuan University 610065 Chengdu China 2. institute of Structure Mechanics China Academy of Engineering Physics 621900 Mianyang China

The nano-silica/polystyrene composite particles were prepared and characterized according to the following steps. First, the nano-silica particles were pretreated with surfactants under ultrasonic field. Second, the dispersion polymerization of styrene in a water/ethanol (1/6, weight ratio) medium, with poly(N-vinyl pyrrolidone) (PVP) as stabilizer and 2.2.-azobisizobu- tyronitrile (AIBN) as initiator in the presence of nano-silica particles was initiated with N2.purging through ultrasonic irradiation by taking its advantages of multieffect, i.e. dispersion, crushing, activation, and initiation. Finally, the polymerization kinetics characteristics were studied, and the encapsulation of composite particles was investigated with optical microscope, SEM, TEM, FTIR, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC).

关键词： composite particle, dispersion polymerization, ultrasonic irradiation.

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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 {2. of engineering physics,mianyang 62.900,china 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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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, china Research Centre of Laser Fusion, Chinese academy of engineering Plysics, mianyang 62.900, china institute of Nuclear physics and Chemistry, Chinese academy of engineering physics, mianyang 62.900, china 1. Precision engineering Research institute Harbin Institute of Technology 150001 Harbin China 2. Research Centre of Laser Fusion Chinese Academy of Engineering Plysics 621900 Mianyang China 3. institute of Nuclear physics and Chemistry Chinese Academy of Engineering Physics 621900 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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Friction-reducing and antiwear behavior of metal halide-stabilized linear phosphazene derivatives as lubricants for a steel-on-steel contact

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Science china(Technological Sciences) 2005年第3期48卷 282-291页

作者： ZHU Jiamei 1,2., LIU Weimin 2.& LIANG Yongmin 2.1. School of chemical engineering and Technology,{2. University of Mining and Technology, Xuzhou 2.1008,{2. 2. State Key Laboratory of Solid Lubrication, Lanzhou institute of chemical physics, Chinese academy of Sciences, Lanzhou 730000,{2. 1. School of chemical engineering and Technology China University of Mining and Technology 221008 Xuzhou China 2. State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences 730000 Lanzhou China

A series of novel metal halide-stabilized linear phosphazene derivatives were synthesized. The friction-reducing and antiwear abilities of the resulting products as the lubricants for a steel-on-steel contact were comparatively investigated on an Optimol SRV oscillating friction and wear tester. The morphology of the worn steel surface was observed on a scanning electron microscope, while the chemical states of some typical elements on the worn steel surface were examined by means of X-ray photoelectron spectroscopy. It was found that both the side branch structures and central metals influenced the friction-reducing and antiwear behaviors of the synthetic derivatives as the lubricants, which was related to the different adsorption activities of the organic compounds composed of different organic ingredients and metallic ions on a nascent metal surface. All the synthetic lubricants except for the iron (III) derivative showed increased antiwear abilities with increasing metallic ionic radius. A protective layer originated from the tribochemical reaction together with the adsorbed boundary lubricating layer containing organic fluorine compounds, nitrogen oxide, and Fe 3 (PO 4 ) 2.plays an important role in improving the friction and wear behavior of the steel-on-steel system.

关键词： metal halide-stabilized linear phosphazene derivatives,lubricant,steel,tribological properties.

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Consecutive reversible ionization-recombination reactions and ionic charge state distribution of Au plasma

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Science china(physics,Mechanics & Astronomy) 2005年第5期48卷 575-584页

作者： ZHU Zhiyan1, ZHU Zhenghe1, TANG Changhuan1, TANG Yongjian2.& GAO Tao1 1. institute of Atomic and Molecular physics, Sichuan University, Chengdu 610065,{2. 2. china academy of engineering physics, mianyang 62.900,{2. 1. institute of Atomic and Molecular physics Sichuan University 610065 Chengdu China 2. china academy of engineering physics 621900 Mianyang China

The present work proposes kinetics of ionization-recombination to study the charge state distribution of Au plasma. The first step is to calculate the average lifetime, energy level structure, degeneracy and partition function of Au48+―Au52. by relativistic quantum mechanics, and next to compute the equilibrium constant and the second-order recombination rate constant by statistical thermodynamics. Based on these data, the differential equations of consecutive reversible ionization-recombination reactions are solved from which the charge state distribution and its average charge are derived. Finally, the influence of electron temperature and density on average charge is given in this paper. It is called the first-principle theory, for no experimental data are needed.

关键词： Au plasma, ionization-recombination dynamics, ionic charge state distribution, average charge.

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