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Science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1586-1592页

作者： LI Jian1,ZHANG Ying1,YAO JiangMing1 & meng jie1,2 1 school of physics,State Key Laboratory of Nuclear physics and Technology,peking university,beijing 100871,china 2 school of physics and Nuclear Energy Engineering,Beihang university,beijing 100191,china school of physics State Key Laboratory of Nuclear Physics and Technology Peking University Beijing China school of physics and Nuclear Energy Engineering Beihang University Beijing China

The configuration-fixed deformation constrained relativistic mean field approach with time-odd component has been applied to investigate the ground state properties of 33Mg with effective interaction *** ground state of 33Mg has been found to be prolate deformed,β2=0.23,with the odd neutron in 1/2[330] orbital and the energy -251.85 MeV which is close to the data -252.06 *** magnetic moment -0.9134 μN is obtained with the effective electromagnetic current which well reproduces the data -0.7456 μN self-consistently without introducing any *** energy splittings of time reversal conjugate states,the neutron current,the energy contribution from the nuclear magnetic potential,and the effect of core polarization are discussed in detail.

关键词： magnetic moment binding energy time-odd component configuration-fixed deformation constrained calculation relativistic mean field theory

Convergence for Imaginary Time Step evolution in the Fermi and Dirac seas

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Science china(physics,Mechanics & Astronomy) 2010年第2期53卷 327-330页

作者： LI FangQiong1,ZHANG Ying2 & meng jie2,3,4 1Guizhou university for Nationalities,Guiyang 550025,china 2State Key Lab Nucl. Phys. & Tech.,school of physics,peking university,beijing 100871,china 3school of physics and Nuclear Energy Engineering,Beihang university,beijing 100191,china 4Department of physics,university of Stellenbosch,Stellenbosch,South Africa Guizhou university for Nationalities Guiyang China State Key Lab Nucl. Phys. & Tech. School of Physics Peking University Beijing China school of physics and Nuclear Energy Engineering Beihang University Beijing China Department of physics University of Stellenbosch Stellenbosch South Africa

The convergence for the Imaginary Time Step (ITS) evolution with time step is investigated by performing the ITS evolution for the Schrdinger-like equation and the charge-conjugate Schrdinger-like equation deduced from Dirac equation for the single proton levels of 12C in both the Fermi and Dirac seas. For the guaranteed convergence of the ITS evolution to the "exact" results,the time step should be smaller than a "critical" time step Δtc for a given single-particle level. The "critical" time step Δtc is more sensitive to the quantum numbers |κ| than to the energy of the single-particle level. For the single-particle levels with the same κ,their "critical" time steps are in the same order. For the single-particle levels with similar energy,a relatively small (large) "critical" time step for larger (smaller) |κ| is needed. These conclusions can be used in the future self-consistent calculation to optimize the evolution procedure.

关键词： Dirac equation Schrdinger-like equation Imaginary Time Step method convergence

Investigation into the rotational bands of ^(185)Pt with the particle-rotor model

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 114-118页

作者： LI GuangShun1,2, ZHOU XiaoHong1,2, ZHANG ShuangQuan3, ZHANG YuHu1 & meng jie3 1 Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 730000, china 2 Graduate university of Chinese Academy of Sciences, beijing 100049, china 3 school of physics and SK Laboratory of Nuclear physics & Technology, peking university, beijing 100871, china Institute of Modern physics Chinese Academy of Sciences Lanzhou China Graduate university of Chinese Academy of Sciences Beijing China school of physics and SK Laboratory of Nuclear physics & Technology Peking University Beijing China

Theoretical calculations have been performed for the ν9/2+[624](i13/2) and ν7/2-[503](f7/2) bands of 185Pt in the framework of particle-rotor model. The band properties of signature splitting and configuration mixing have been analyzed. The level energy and signature splitting before the band crossing can be well interpreted by introducing triaxiality. The positive-parity yrast band is pro posed to be dominated by the ν9/2+[624](i13/2) component, while the negative-parity band shows strong mixing of ν7/2-[503](f7/2) and ν9/2-[505](h9/2) configurations.

关键词： High-spin states particle-rotor model signature splitting configuration mixing

Selected issues at the interface between nuclear physics and astrophysics as well as the standard model

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 119-123页

作者： meng jie1,2,3, NIU ZhongMing1, LIANG HaoZhao1 & SUN BaoHua2,4 1State Key Laboratory of Nuclear physics and Technology, school of physics, peking university, beijing 100871, china 2school of physics and Nuclear Energy Engineering, Beihang university, beijing 100191, china 3Department of physics, university of Stellenbosch, Stellenbosch, South Africa 4Justus-Liebig-Universita¨t Giessen, Heinrich-Buff-Ring 14, Giessen 35392, Germany State Key Laboratory of Nuclear physics and Technology School of Physics Peking University Beijing China school of physics and Nuclear Energy Engineering Beihang University Beijing China Department of physics University of Stellenbosch Stellenbosch South Africa Justus-Liebig-Universität Giessen Giessen Germany

The density functional theory (DFT) with a minimal number of parameters allows a very successful phenomenological description of ground state properties of nuclei all over the periodic table. The recent developments on the application of the covariant density functional theory as well as its extensions by the group in beijing for a series of interests and hot topics in nuclear astrophysics and nuclear structure are reviewed, including the rapid neutron-capture process, Th/U chronometer, and isospin corrections for superallowed β transitions.

关键词： rapid neutron-capture process nuclear chronometer isospin symmetry-breaking corrections

Optimization of the imaginary time step evolution for the Dirac equation

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Science china(physics,Mechanics & Astronomy) 2011年第2期54卷 231-235页

作者： LI FangQiong1,ZHANG Ying2,LIANG HaoZhao2,3 & meng jie4,2,5 1Guizhou university for Nationalities,Guiyang 550025,china 2State Key Lab Nuclear physics & Technology,school of physics,peking university,beijing 100871,china 3Institut de Physique Nucle’aire,IN2P3-CNRS and Universite’ Paris-Sud,F-91406 Orsay Cedex,France 4school of physics and Nuclear Energy Engineering,Beihang university,beijing 100191,china 5Department of physics,university of Stellenbosch,Stellenbosch,South Africa Guizhou university for Nationalities Guiyang China State Key Lab Nuclear physics & Technology School of Physics Peking University Beijing China Institut de Physique Nucléaire IN2P3-CNRS and Université Paris-Sud Orsay Cedex France school of physics and Nuclear Energy Engineering Beihang University Beijing China Department of physics University of Stellenbosch Stellenbosch South Africa

Taking the single neutron levels of 12C in the Fermi sea as examples,the optimization of the imaginary time step(ITS) evolution with the box size and mesh size for the Dirac equation is *** the weakly bound states,in order to reproduce the exact single-particle energies and wave functions,a relatively large box size is *** long as the exact results can be reproduced,the ITS evolution with a smaller box size converges faster,while for both the weakly and deeply bound states,the ITS evolutions are less sensitive to the mesh ***,one can find a parabola relationship between the mesh size and the corresponding critical time step,i.e.,the largest time step to guarantee the convergence,which suggests that the ITS evolution with a larger mesh size allows larger critical time step,and thus can converge faster to the exact *** conclusions are very helpful for optimizing the evolution procedure in the future self-consistent calculations.

关键词： Dirac equation Schrdinger-like equation imaginary time step method convergence

High-sensitivity photovoltage based on the interfacial photoelectric effect in the SrTiO_(3-δ)/Si heterojunction

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 2080-2083页

作者： WEN Juan 1,GUO HaiZhong 1,XING jie 2,Lü HuiBin 1,JIN Kui-Juan 1,HE meng 1 & YANG GuoZhen 1 1 beijing National Laboratory for Condensed Matter physics,Institute of physics,Chinese Academy of Sciences,beijing 100190,china 2 school of Materials Sciences and Technology,china university of Geosciences,beijing 100083,china beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing China school of Materials Sciences and Technology China University of Geosciences Beijing China

A high sensitivity photovoltaic effect has been observed in a heterojunction composed of n-type wide bandgap oxide SrTiO 3-δ and p-type Si fabricated by laser molecular beam *** responsivity of open-circuit photovoltage can reach 10 4 V/W without any amplification under zero bias for the wavelength range from visible to near infrared light in nW-μW *** attribute the high performance of the photovoltage responsivity to the interfacial photoelectric effects in the SrTiO 3-δ /Si *** the experimental results,some ideas can be generalized to improve photovoltaic efficiency and develop high sensitivity photodetectors with wide bandgap oxide materials and Si.

关键词： SrTiO 3-δ/Si heterojunction interfacial photoelectric effect photovoltage

Disassembly intermediates of RbsD protein remain oligomeric despite the loss of an intact secondary structure

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Science china(Life Sciences) 2009年第11期52卷 997-1002页

作者： FENG YongJun1, ZHANG meng2, HU MingXi1, ZHENG jie1, JIAO WangWang2 & CHANG ZengYi2 1 school of Life Science, beijing Institute of Technology, beijing 100081, china 2 school of Life Sciences, National Laboratory of Protein Engineering and Plant Genetic Engineering, Center for Protein Science, peking university, beijing 100871, china school of Life Science Beijing Institute of Technology Beijing China school of Life Sciences National Laboratory of Protein Engineering and Plant Genetic Engineering Center for Protein Science Peking University Beijing China

Many proteins exist as homo-oligomers in living organisms wherein the change of oligomeric status apparently serves as an effective means for modulating their biological activities. We have previously reported that the homo-decameric RbsD from Escherichia coli undergoes stepwise disassembly and non-stepwise reassembly. Here the structural status of the urea-induced RbsD disassembly intermediates was examined, mainly using urea-containing polyacrylamide gel electrophoresis and chemical cross-linking. Such intermediates were found to remain oligomeric while losing their intact secondary structures. Such disassembly intermediates were able to effectively refold when the concentration of the urea denaturant was reduced to a lower level, or to refold/reassemble into the native decamers when urea was completely removed, as detected by non-denaturing polyacrylamide gel electrophoresis. These novel observations strongly suggest that the assembly of oligomeric proteins may occur before the completion of subunit folding.

关键词： RbsD oligomeric protein oligomeric intermediate refolding reassembly

A first-principles investigation into the hydrogen bond interaction in β-HMX

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Science china(physics,Mechanics & Astronomy) 2010年第6期53卷 1080-1085页

作者： CHEN Fang 1 ,ZHANG Hong 1,2,ZHAO Feng 3 ,meng ChuanMin 3 & CHENG XinLu 1 1 Institute of Atomic and Molecular physics,Sichuan university,Chengdu 610065,china 2 school of Physical Science and Technology,Sichuan university,Chengdu 610065,china 3 Laboratory for Shock Wave and Detonation physics Research,Southwest Institute of Fluid physics,china Academy of Engineering physics,Mianyang 621900,china Institute of Atomic and Molecular physics Sichuan University Chengdu China school of Physical Science and Technology Sichuan University Chengdu China Laboratory for Shock Wave and Detonation physics Research Southwest Institute of Fluid Physics China Academy of Engineering Physics Mianyang China

A theoretical study of structural and electronic properties of β-HMX crystal is performed using density-functional theory(DFT). The total density of states(TDOS) is presented. The atomic orbit projected density of state(PDOS) from the p-type orbit of C,N,O and the s-type orbit of H is discussed. The study by analyzing the PDOS shows that the structure of β-HMX crystal possesses C-H···O intra- and inter-molecular hydrogen-bonding. There exists a hydrogen bonding between H5 -1s and O12 -2p orbits,between H19 -1s and O28 -2p orbits of intra molecules,and between H19 -1s and O24 -2p orbits of inter molecules. The Mulliken population analysis is also made.

关键词： structural property hydrogen bond β-HMX population analysis

Relativistic description of second-order correction to nuclear magnetic moments

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Relativistic description of second-order correction to nucle...