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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 {2.,chinese academy of sciences,Lanzhou 730000,china 2.7} institute of Atomic energy,Beijing 102.13,china 3 Center of Theoretical Nuclear {2.,National Laboratory of Heavy Ion Research Facility in Lanzhou,Lanzhou 730000,china) 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 Atomic {2. 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

Diffuse interstellar absorption bands

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Science china(physics,Mechanics & Astronomy) 2009年第4期52卷 489-501页

作者： XIANG FuYuan1,2.liANG Shunlin2.& li AiGen2.3 1 Faculty of Materials,Photoelectronics and physics,Xiangtan University,Xiangtan 411105,china 2.Department of physics and Astronomy,University of Missouri,Columbia,MO 652.1,USA 3 Purple Mountain Observatory,chinese academy of sciences,Nanjing 2.0008,china 1. Faculty of Materials Photoelectronics and Physics Xiangtan University Xiangtan 411105 China 2. Department of physics and Astronomy University of Missouri Columbia MO 65211 USA 3. Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

The diffuse interstellar bands(DIBs) are a large number of absorption bands that are superposed on the interstellar extinction curve and are of interstellar origin. Since the discovery of the first two DIBs in the 192.s,the exact nature of DIBs still remains unclear. This article reviews the history of the detections of DIBs in the Milky Way and external galaxies,the major observational characteristics of DIBs,the correlations or anti-correlations among DIBs or between DIBs and other interstellar features(e.g. the prominent 2.75 Angstrom extinction bump and the far-ultraviolet extinction rise),and the proposed candidate carriers. Whether they are also present in circumstellar environments is also discussed.

关键词： astrophysics interstellar matter interstellar extinction diffuse interstellar band circumstellar environment

Accurate studies on dissociation energies of diatomic molecules

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Science china(physics,Mechanics & Astronomy) 2007年第5期50卷 611-621页

作者： SUN weiguo1, FAN QunChao1 & REN WeiYi1,2.1 institute of {2., Sichuan University, Chengdu 610065, china 2.institute of Theoretical {2., Xihua Normal University, Nanchong 637002. china institute of physics Sichuan University Chengdu 610065 China institute of Theoretical physics Xihua Normal University Nanchong 637002 China

The molecular dissociation energies of some electronic states of hydride and N2.molecules were studied using a parameter-free analytical formula suggested in this study and the algebraic method (AM) proposed recently. The results show that the accurate AM dissociation energies DeAM agree excellently with experimental dissociation energies Deexpt, and that the dissociation energy of an electronic state such as the 2.Δg state of 7li2.whose experimental value is not available can be predicted using the new formula.

关键词： algebraic method, diatomic molecule, vibrational energy, dissociation energy

Killing effect of chinese hamster V79 cells exposed to accelerated carbon ions and RBE determination

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Nuclear Science and Techniques 2002年第4期13卷 259-263页

作者： li Qiang, ZHOU Guang-Ming, WANG Ju-Fang, li Wen-Jian, WEI Zeng-Quan({2. of Modern physics, the chinese academy of sciences, Lanzhou 730000) institute of Modern physics the Chinese Academy of Sciences Lanzhou 730000

Survival curves of chinese hamster V79 cells exposed to accclerated carbon ions with linear {2. transfers of 12..5, 2.0 and 700 keV/μm were measured, respectively. Inactivation cross sections corresponding to the irradiation above were deduced from the V79 cell survival curves. They are 7.86±0.17, 10.44±1.11 and 32.32.3.58 μm2.in turn. With the surviving response of V79 cells to 60Co γ-rays as a reference value, relative biological effectiveness at 10%, 2.%, 50% and 80% survival levels were given for the accelerated carbon ions. The results showed that carbon ions with LET of 12..5 keV/μm had a higher value of RBE at all the four survival levels than the carbon ions with other LETs. It was prompted that the maximum value of RBE for the V79 cell surviving as the biological endpoint emerged at the LET below 2.0 keV/μm for carbon ions.

关键词：放射生物学碳离子 V79细胞

Transient Temperature of liquid on Micro Metal LayerHeated by Pulsed Laser

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Journal of Thermal Science 1999年第2期8卷 125-130页

作者： li Ji Zhang Zhengfang liu Dengging({2. of Engineering Thermophysics, chinese academy of sciences, Beijing 100080, china) institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China

In this paper the transient temperature of liquid on micro metal layer heated by pulsed high {2. laser is simulatedby numerical method, especially around the theoretical homogeneous boiling point(THBP). The relationshipbetween temperature rising rate and laser fiuence is obtained; and under different temperature rising rate thedistributions of temperature in liquid and metal around the THBP are obtained. With numerical simulation therelation between the temperatUre rising rate and laser parameters (fluence and pulse width) is known and so in thefuture the rapid transient boiling phenomenon could be studied and analyzed.

关键词： homogeneous boiling heat conduction numerical method.

Tunneling conductance in graphene ferromagnet/p wave superconductor junctions

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Science china(physics,Mechanics & Astronomy) 2012年第4期Mechanics & Astronomy) .卷 649-653页

作者： li XiaoWei 1,2.,CHEN HuaBao 1 & liU ShuJing 1 1 School of {2. and Electronic Electrical Engineering,Huaiyin Normal University,Huaian 2.3300,china 2.State Key Laboratory of Functional Materials for Informatics,Shanghai institute of Microsystem and Information Technology,chinese academy of sciences,Shanghai 2.0050,china 1. School of physics and Electronic Electrical Engineering Huaiyin Normal University Huaian 223300 China2. State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China

Using the extended Blonder-Tinkham-Klapwijk formalism,we investigate the conductance spectra of graphene ferromagnet/p wave superconductor *** is found that the conductance spectra are affected by the p wave pairing *** ferromagnetic exchange energy in the ferromagnet can suppress Andreev retroreflection but enhance the specular Andreev reflection in graphene ferromagnet/p wave superconductor *** conductance decreases with increasing exchange energy Eh for EhEF.

关键词： graphene ferromagnet p wave superconductor tunneling conductance

Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2.molecule

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2. SUN weiguo1, HOU Shilin3 & FENG Hao4 1. {2. of physics, College of Chemical Engineering, Sichuan University, Chengdu 610065, china 2. {2. of Theoretical physics, Xihua Normal University, Nanchong 637002. china 3. Department of physics, china Oceanography University, Qingdao 2.6003, china 4. College of physics, Sichuan University, Chengdu 610065, china 1. institute of physics College of Chemical Engineering Sichuan University 610065 Chengdu China 2. institute of Theoretical physics Xihua Normal University 637002 Nanchong China 3. Department of physics China Oceanography University 266003 Qingdao China 4. College of physics Sichuan University 610065 Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2.molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

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 {2. of Atomic energy,Beijing 102.13,china 2.Center of Theoretical Nuclear physics,National Laboratory of Heavy Ion Research Facility in Lanzhou,Lanzhou 730000,china 3 {2. of Modern physics,chinese academy of {12.,Lanzhou 730000,china) china institute of Atomic {2. Beijing 102413China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China china institute of Atomic {2. 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 {2. 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

Understanding the defect chemistry of oxide nanoparticles for creating new functionalities:A critical review

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Science china Chemistry 2011年第6期54卷 876-886页

作者： li GuangShe,li liPing & ZHENG Jing State Key Laboratory of Structural Chemistry Fujian institute of Research on the Structure of Matter,chinese academy of sciences,Fuzhou 350002.china 1. State Key Laboratory of Structural Chemistry Fujian institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou 350002 China

This work presents a critical review on the studies of defect chemistry of oxide nanoparticles for creating new functionalities pertinent to energy applications including dilute-magnetic semiconductors,giant-dielectrics,or white light *** is placed on the relationships between the internal structure and defective surfaces of oxide nanoparticles and their synergy in tailoring the materials *** review is arranged in a sequence:(1) structural fundamentals of bulk oxides,using TiO2.as a model simple oxide to highlight the importance of polymorphs in tuning the electronic structures;(2. structural features of simple oxide nanoparticles distinct from the bulk,which show that nanoparticles can be considered as a special solid under the compression as originated from the surface defect dipole-dipole interactions;and(3) new functions achieved through extending the defect chemistry concept to the assembled architectures or multi-component oxide nanoparticles,in which defect surfaces enable the localized electrons or intermediate levels to produce giant dielectric performance or tunable light *** is concluded that understandings of defect chemistry provide diverse possibilities to manipulate electrons in oxide nanoparticles for functionalities in energy-relevant applications.

关键词： nanoparticles defect chemistry surfaces functionalities