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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, china Academy of Engineering Physics,{2., 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).

Theoretical study of aging effects on LaNi_(5) tritium storage

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 676-686页

作者： PING Feilin1,2. JIANG Gang1, ZHANG Lin2.& ZHU Zhenghe1 1. Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, china 2. Research Center of Laser Fusion, mianyang 62.900, china 1. Institute of Atomic and Molecular Physics Sichuan University 610065 Chengdu China 2. Research Center of Laser Fusion 621900 Miangyang China

The electronic structure and energy of La2.i10H12.and La2.i10H11He (He is at tetrahedral, octahedral or twelve-face polyhedral interstitials) double cells have been calculated using the density functional theory. Their equilibrium structure, energy bands, electronic density of states (DOS) and X-ray diffraction are presented and discussed. The results indicate the helium-3 produced due to the decay of tritium is most possibly sited at twelve-face polyhedral and octahedral interstices and changes the thermodynamic properties of LaNi5 tritide system. The changes due to aging such as the reduction in the isotherm plateau pressure, increase of the isotherm plateau slope, and appearance of deeply trapped hydrogen are caused not only by the lattice expansion, but also by modification of the electronic structure due to the presence of He.

关键词： LaNi5 alloy, density functional theory, electronic structure, aging.

Distribution and characteristics of gravelly soil liquefaction in the Wenchuan M_s 8.0 earthquake

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 167-175页

作者： Cao Zhenzhong1,Hou Longqing2.Xu Hongmei2.and Yuan Xiaoming1 1. Institute of Engineering Mechanics,china Earthquake Administration,Harbin 150080,china 2. East{2. Institute of Technology,Fuzhou 344000,china Institute of Engineering Mechanics China Earthquake Administration Harbin 150080 China

In this paper,a distribution map of gravelly soil liquefaction that was caused by the Wenchuan M8.0 earthquake in china is proposed based on a detailed field investigation and an analysis of geological soil profiles. The geological background of the earthquake disaster region is summarized by compiling geological cross sections and borehole logs. Meanwhile,four typical liquefied sites were selected to conduct sample drillings,dynamic penetration tests (DPT),and shear wave velocity tests,to understand the features of liquefied gravelly soil. One hundred and eighteen (118) liquefied sites were investigated shortly after the earthquake. The field investigation showed:(1) sandboils and waterspouts occurred extensively,involving thousands of miles of farmland,12. villages,eight schools and five factories,which caused damage to some rural houses,schools,manufacturing facilities and wells,etc.; (2. the Chengdu plain is covered by a gravelly soil layer with a thickness of 0 m to 541 m according to the geological cross sections; (3) there were 80 gravelly soil liquefied sites in the Chengdu plain,shaped as five belt areas that varied from 2. km to 40 km in length,and about ten gravelly soil liquefied sites distributed within mianyang area; and (4) the grain sizes of the sampled soil were relative larger than the ejected soil on the ground,thus the type of liquefied soil cannot be determined by the ejected soil. The gravelly soil liquefied sites are helpful in enriching the global database of gravelly soil liquefaction and developing a corresponding evaluation method in further research efforts.

关键词： gravelly soil liquefaction borehole soil profile geological cross section grain size distribution Wenchuan earthquake

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, china 2. china Academy of Engineering Physics,{2., china 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.

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

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Science china(Physics,Mechanics & 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 Engineering 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.

Studies on the analytical potential energy function of diatomic molecular ion XY^+ using variational method

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Science china(Physics,Mechanics & Astronomy) 2004年第2期47卷 154-164页

作者： LIU Guoyue1,3, SUN Weiguo1,2.& FENG Hao1 1. Institute of Physics, Sichuan University, Chengdu 610065, china 2. College of Chemical Engineering, Sichuan University, Chengdu 610065, china 3. {2. Teacher抯 College, {2. 62.000, china Correspondence should be addressed to Sun Weiguo (e-mail: weiguosun@*** or guoyueliu@ ***) 1. Institute of Physics Sichuan University 610065 Chengdu China 2. mianyang Teacher's College 621000 Mianyang China 3. College of Chemical Engineering Sichuan University 610065 Chengdu China

A new analytical potential energy function for diatomic molecular ion XY+ is proposed based on the energy consistent method (ECM). The Coulomb potential included in the new ionic potential contains multipole corrections, converges quickly and is variationally, changeable. The new potential and the ECM are applied to variationally studying the potential energies of eight electronic states of several diatomic molecular ions: the A2. state of CO+, the X2. g + state of Li 2.+ , the X2. g + state of He 2.+ , the 12.u state of Na 2.+ , the A2.u state of N 2.+ , the X1∑+ state of KrH+, the X2.+ state of SiO+ and the A2. state of SO+ ion. The present results agree excellently with the experiment-based Rydberg-Klein-Rees (RKR) potentials, and are superior to the commonly used Huxley-Murrell-Sorbie (HMS) analytical potentials, and are better in some cases than some quantum mechanicalab initio potentials in the ionic asymptotic and dissociation regions.

关键词： potential energy, diatomic ion, electronic state, variational method.

Pressure effects on the absorption spectra of Na doped in solid Ar

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Science china(Physics,Mechanics & Astronomy) 2004年第5期47卷 550-560页

作者： CUI Tian1, HE Wenjiong1, YIN Hongwei1, MA Yanming1, CHEN Changbo1, ZOU Guangtian1, WEI Mengfu2.& CHEN Changan2.1. National Laboratory of Superhard Materials, Jilin University, Changchun 130012. china 2. china Academy of Engineering Physics, Box 919-71,{2., china 1. National Laboratory of Superhard Materials Jilin University 130012 Changchun China 2. china Academy of Engineering Physics Box 919-71 621900 Mianyang China

In this work, the pressure influence on the absorption spectra of Na in solid Ar for various trapping sites is extensively investigated at T = 10 K and in the pressure range from 0 to 2.4 GPa by using Monte Carlo method with a constant pressure ensemble (NPT). For the trapping sites of nv = 1, 2. the absorption spectral widths increase progressively, the absorption peaks and the centroid spectral shift (CSS) tend to have a red shift with pressure increasing, even though there is no local structural symmetry change around Na atom caused by pressure. Highly symmetrical trapping site structure (nv = 1) determines a highly symmetrical triplet absorption feature at a low pressure. With the increase in pressure, the action from the Ar crystal field on the three energy levels of the 3p excited state of Na atom increases, resulting in the overlap of the three peaks. Low symmetrical trapping site structure (nv = 2. yields a low symmetrical triplet absorption pattern in which a large separation between the single?and the double?peaks exists at a low pressure. With the increase in pressure, the splitting between the singlet and the doublet increases, and the doublet merges as the pressure is larger than 2.4 GPa.

关键词： Monte Carlo, simulation, absorption spectra, doped system, pressure effect.

Synthesis and Luminescence Properties of Red Phosphor CaO:Eu^(3+)

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Journal of Wuhan University of Technology(Materials Science) 2009年第1期24卷 20-24页

作者：康明 School of Material Science and Engineering Southwest University of Science and Technology College of Materials Science and Engineering Sichuan University

Ca（NO3）2.4H2., Eu（NO3）3 and H2.2.4·2.2. were adopted to synthesize CaO： Eu3＋ with the chemical co-precipitation method, and the effects of the calcination temperature and Eu3＋ doping concentration on the phosphor structure and its luminescent properties were investigated by TG-SDTA, XRD, and PL-PLE. The results confirm that the Eu3＋ ions as luminescent centers substi-tutes Ca2. sites without changing the crystal structure of cubic CaO. The optimum calcination tem-perature and the optimum concentration of Eu3＋ are 1 100 ℃ and 1 mol%, respectively, under which the best crystallinity and highest PL intensity appeared. The maximum emission wavelength is 592.nm （5D0→7F1） which is excited by xenon lamp with the wavelength of 2.0-2.0 nm, indicating that the Eu3＋ ion mainly locates in the symmetric position （Oh） in the crystal lattice of CaO.

关键词： red phosphor CaO Eu^3+ co-precipitation method rare earths

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 Xinhua31. Institute of Nuclear Physics and Chemistry, china Academy of Engineering Physics, 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.