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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 {2. of engineering physics mianyang Sichuan 62.900 china 黄奕刚institute of Chemical Materials china {2. of engineering physics mianyang Sichuan 62.900 china 龙新平institute of Chemical Materials china {2. of engineering physics mianyang Sichuan 62.900 china 汤业鹏institute of Chemical Materials china {2. of engineering physics mianyang Sichuan 62.900 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(2.)indE may be important.

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

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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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).

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

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.

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

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Science china(physics,{2. & 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.

Effects of Processing Parameters on Weld Geometries in Electron Beam Welding Based on Partial Correlation Analysis

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稀有金属材料与工程 2011年第S4期40卷 30-34页

作者： Shen X F,Huang W R,Zhang Y Z 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

Accelerating voltage,electron beam current,welding speed constitutes the main electron beam welding process parameters,while the penetration depth and depth-width ratio are two of the most important characteristic parameters of the weld *** complex interactions exists between the five variables,so the analysis of a single process parameter on one of weld geometries is affected by the other process parameters,and the impact of these interference parameters should be excluded to find the real relationship between the variables where partial correlation analysis provides such a *** of the accelerating voltage,electron beam current,welding speed of electron beam welding process parameters on weld geometries is analyzed by using partial correlation *** priority order of adjustment of process parameters is obtained,namely:in order to obtain a larger depth-width ratio indicators,it should be taken firstly to increase the beam current and accelerating voltage,and then to raise the welding speed;in order to obtain greater penetration depth,it is preferred to increase the beam current,followed by increasing the accelerating voltage,and reducing the welding speed finally.

关键词： electron beam welding process parameters characteristic parameters of weld morphology partial correlation analysis

Theoretical and experimental researches on C-band three-cavity transit-time effect oscillator

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Science china(physics,{2. & Astronomy) 2004年第3期47卷 310-329页

作者： FAN Zhikai1, LIU Qingxiang1, CHEN Daibing1, TAN Jie1 & ZHOU Haijing2.1. institute of Applied Electronics, Chinese academy of {2. physics, mianyang 62.900, china 2. institute of Applied physics and Computational Mathematics, Beijing 100088, china 1. institute of Applied Electronics Chinese Academy of Engineering Physics 621900 Mianyang China 2. institute of Applied physics and Computational Mathematics 100088 Beijing China

The C-band three-cavity transit-time effect oscillator (3C TTTO) is a novel high power microwave device based on the transit-time effect of the three-cavity (3C) resonator. The operational principle of this device is briefly expounded in this paper, and the theoretical and experimental researches on the radial insulation diode, the 3C resonator, the double-gap output cavity and the circular waveguide bevel cut radiation antenna are presented in detail. By using the analytic method, the eigen modes and their field distributions of the 3C resonator are developed, and some basic laws of the transit-time effect are obtained in non-π mode field of the 3C resonator. At last, the experimental results are given. This device generated RF peak power in excess of 400MW with 15ns FWHM, and its beam-wave power conversion efficiency is about 17%.

关键词： C-band, three-cavity (3C) resonator, transit-time effect, high power microwave, oscillator.

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

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Science china(physics,{2. & 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 Xinhua31. institute of Nuclear physics and Chemistry,{2., mianyang 62.900, china 2. Department of physics, Peking university, Beijing 100871, china 3. institute of Atomic and Molecular physics, Sichuan University, Chengdu 610065, china 1. institute of Nuclear physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China 2. Department of physics Peking university Beijing 100871 China 3. institute of Atomic and Molecular physics Sichuan University Chengdu 610065 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.