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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 {2., Sichuan University, Chengdu 610065, china 2. china Academy of Engineering {2., Mianyang 62.900, china institute of atomic and Molecular {2. Sichuan University Chengdu China china Academy of Engineering physics 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.

Probing nuclear Symmetry energy with Giant Dipole Resonances in Finite Nuclei

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原子核物理评论 2009年第S1期26卷 181-184页

作者： CAO Li-gang1,3,MA Zhong-yu2.3 (1 institute of Modern physics,Chinese Academy of Sciences,Lanzhou 730000,{2. 2.3},beijing 102.13,{2. 3 Center of Theoretical nuclear physics,National Laboratory of Heavy Ion Research Facility in Lanzhou,Lanzhou 730000,{2.) institute of Modern physics Chinese Academy of SciencesLanzhou 730000China Center of Theoretical nuclear physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China china institute of {2. energy Beijing 102413China Center of Theoretical nuclear physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China

The relationship between the centroid energies of the isovector giant dipole resonance of finite nuclei and the symmetry energy has been studied. It is found the excitation energies of the dipole resonance in finite nuclei are correlated linearly with the symmetry energy at and below the saturation density. This linear correlation leads to the symmetry energy at the saturation density at the interval 33.0 MeV ≤ S(ρ0) ≤ 37.0 MeV,and the symmetry energy at ρ = 0.1 fm-3 at the interval 2..2.2..5 MeV. It is proposed that a precise measurement of the dipole mode in nuclei could set up an important constraint on the equation of state for nuclear matter.

关键词： symmetry energy dipole resonance Pygmy resonance

The anharmonic effect study of coupled Morse oscillators for the unimolecular reaction

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Science china Chemistry 2008年第12期51卷 1146-1152页

作者： YAO Li1,2.& LIN Sheng-Hsien2.31 department of physics, Dalian Maritime University, Dalian 11602., {2. 2.institute of atomic and Molecular Sciences, Academia Sinica, Taipei 10764, {2. 3 department of Applied Chemistry and institute of Molecular Sciences, Chiao-Tung University, Hsinchu 30051, Taiwan, {2. department of physics Dalian Maritime University Dalian China institute of atomic and Molecular Sciences Academia Sinica Taipei China department of Applied Chemistry and institute of Molecular Sciences Chiao-Tung University Hsinchu Taiwan China

The importance of anharmonic effect in dissociation of molecular systems especially clusters has been noted. In this paper, we shall study the effect of coupled anharmonic oscillator of the standard bilinear form (SBF) Morse oscillator (MO) potential on unimolecular reaction. We shall use the systematic theoretical approach, YL method, proposed by Yao and Lin (YAO L, et. al. J Phys Chem A, 2.07, 111(2.): 672.-672.), which can evaluate anharmonic effects on the rate constants based on the transition state theory. In treating the anharmonic effect with the Morse oscillator potential on unimolecular reactions under collision-free conditions by using the RRKM (Rice-Ramsperger-Kassel-Marcus) theory, the in-verse Laplace transformation of the partition functions was used to obtain the total amount of state and density of state by using the first-order and the second-order approximations of the saddle-point method. To demonstrate the anharmonic effect of the SBF Morse model, we choose some model systems and a real reaction as examples.

关键词： anharmonic effect standard bilinear form Morse oscillator rate constant RRKM theory

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 {2., Sichuan University, Chengdu 610065, china 2. Research Center of Laser Fusion, Mianyang 62.900, china institute of atomic and Molecular {2. Sichuan University Chengdu China Research Center of Laser Fusion 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.

Half-lives and fine structure for the α decay of deformed even-even nuclei

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 24-31页

作者： NI DongDong1,2.& REN ZhongZhou1,2.3 1department of physics, Nanjing University, Nanjing 2.0093, {2. 2.avli institute for Theoretical physics {2., beijing 100190, {2. 3Center of Theoretical nuclear physics, National Laboratory of Heavy-Ion Accelerator, Lanzhou 730000, {2. department of physics Nanjing University Nanjing China Kavli institute for Theoretical physics {2. Beijing China Center of Theoretical nuclear physics National Laboratory of Heavy-Ion Accelerator Lanzhou China

The α-decay properties of well-deformed even-even nuclei are systematically calculated within the multichannel cluster model (MCCM). Instead of working in the WKB framework, the quasibound solution to the coupled Schro¨dinger equation is presented with outgoing wave boundary conditions, and the coupling potential is taken into full account in terms of the general quantum theories. The calculated α-decay half-lives are found to agree well with the experimental data with a mean factor of less than 2. The fine structure observed in α decay is also well reproduced by the four-channel microscopic calculation. Very strikingly, the MCCM can give relatively precise descriptions of the branching ratio to excited 4+ states, which is often overestimated in the usual WKB calculations. We expect it to be a significant development of theoretical models toward quantitative descriptions of α transitions to high-spin daughter states.

关键词： α decay half-lives cluster model coupled channel approach

fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2.3 , ZHAO Xia~4, SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of nuclear Analysis Techniques, institute of High {2. physics, Chinese Academy of Sciences, beijing 100049, china 2. Graduate School of Chinese Academy of Sciences, beijing 100049, china 3. department of physics, Zhoukou Normal University, Zhoukou 466100, china 4. Research Imaging Center, University of Texas Health Science Center, San Antonio, Texas 782.9, USA 5. National ASIC Design and Engineering Center, institute of Automation, Chinese Academy of Sciences, beijing 100049, china 6. department of physics, Zhejiang University, Hangzhou 31002., china) Key Laboratory of nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Graduate School of Chinese Academy of Sciences Beijing 100049 China department of physics Zhoukou Normal University Zhoukou 466100 China Research Imaging Center University of Texas Health Science Center San Antonio TX 78229 United States National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing 100049 China department of physics Zhejiang University Hangzhou 310027 China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

Random Phase Approximation in Relativistic Approach

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原子核物理评论 2009年第S1期26卷 49-54页

作者： MA Zhong-yu1,2.YANG Ding1,TIAN Yuan1,CAO Li-gang2.3(1 china institute of atomic energy,beijing 102.13,{2. 2.Center of Theoretical nuclear physics,National Laboratory of Heavy Ion Research Facility in Lanzhou,Lanzhou 730000,{2. 3 institute of Modern physics,Chinese Academy of Sciences,Lanzhou 730000,{2.) china institute of {2. energy Beijing 102413China Center of Theoretical nuclear physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China china institute of {2. energy Beijing 102413China Center of Theoretical nuclear physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China institute of Modern physics Chinese Academy of SciencesLanzhou 730000China

Some special issues of the random phase approximation(RPA) in the relativistic approach are reviewed. A full consistency and proper treatment of coupling to the continuum are responsible for the successful application of the RPA in the description of dynamical properties of finite nuclei. The fully consistent relativistic RPA(RRPA) requires that the relativistic mean filed (RMF) wave function of the nucleus and the RRPA correlations are calculated in a same effective Lagrangian and the consistent treatment of the Dirac sea of negative energy states. The proper treatment of the single particle continuum with scattering asymptotic conditions in the RMF and RRPA is discussed. The full continuum spectrum can be described by the single particle Green's function and the relativistic continuum RPA is established. A separable form of the paring force is introduced in the relativistic quasi-particle RPA.

关键词： fully consistent RRPA coupling to the continuum pairing correlation

Surface modification of γ-Al_2._3 by sodium ions

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Chinese Science Bulletin 2001年第3期46卷 188-193页

作者： DENG Feng, YUE Yong, DU Youru, YE Chaohui, KONG Yuhua, WANG Guoxing & LI Xiaoding1. Laboratory of Magnetic Resonance and atomic and Molecular physics, Wuhan {2. of physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, china 2. Hubei {2. of Chemistry, Wuhan 430074, china Laboratory of Magnetic Resonance and atomic and Molecular physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China Hubei institute of Chemistry Wuhan China

1H/2.Na double resonance NMR techniques were employed to study the modification of surface hydroxyls on Y-Al2.3 by sodium ions. 1H-2.Na cross polarization (CP) experiment can resolve three kinds of sodium cations that are closely associated with surface hydroxyl groups, while the signal of deposited salt-Na2.O3, which is not connected to surface hydroxyl groups, is completely suppressed. 1H{2.Na} spin echo double resonance experiments reveal the surface modification in more detail. At low Na+ coverage (5%, 10%), the acidic hydroxyl groups are preferentially coordinated with sodium ions, while both the acidic and the basic hydroxyl groups are accessible for sodium ions at highcoordination that causes proton of the OH groups to be easily dissolved, which is evidenced by the fact that with calcination temperature of the catalysts increasing, the acidic hydroxyl groups are preferentially removed and only the basic hydroxyl groups remain when the calcination temperature is raised to 600℃.

关键词： surface modification γ-Al2.3 NMR hydrodesulfu-rization catalyst.

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2. SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3, SUN Xinmin3, ZHAO Wenjun3 & CHENG Huansheng4 1. Faculty of Physical Engineering, Zhengzhou University, Zhengzhou 450052. china 2. department of {2., beijing Normal University, beijing 100875, china 3. institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 450000, china 4. institute of Modern {2., Fudan University, Shanghai 2.0433, china Faculty of Physical Engineering Zhengzhou University Zhengzhou China department of physics Beijing Normal University Beijing China institute of Cultural Relic and Archaeology of Henan Province Zhengzhou China institute of Modern physics Fudan University Shanghai China

34 samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.