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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 73.000, 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 & {3. 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

Shape phase transitions in nuclei:Effective order parameters and trajectories

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 88-97页

作者： ZHANG Yu1,2, HOU ZhanFeng2 & LIU YuXin2,3.1Department of Physics, Liaoning Normal university, Dalian 116029, china 2Department of Physics and the State Key laboratory of {3. Physics and technology, peking university, beijing 100871, china 3.enter of Theoretical {3. Physics, National laboratory of Heavy Ion Accelerator, Lanzhou 720000, china Department of Physics Liaoning Normal University Dalian China Department of Physics and the State Key laboratory of nuclear Physics and technology Peking University Beijing China Center of Theoretical nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou China

We analyze systematically the effective order parameters in nuclear shape phase transition both in experiments and in the interacting boson model. We find that energy ratios and B(E2) ratios can distinguish the first from the second-order phase transition in theory above a certain boson number N (about 50), but in experiments, only those quantities, such as E(L1+)/E(02+) and B(E2; (L+2)1 → L1)/B(E2; 21 → 01), etc., of which the monotonous transitional behavior in the second-order phase transition is broken in the first order phase transition independent of N, are qualified as the effective order parameters. By implementing the originally proposed effective order parameters and the new ones, we find that the isotones with neutron number Nn = 62 are a trajectory of the second order phase transition. In addition, we predict that the transitional behavior of isomer shifts of Xe, Ba isotopes and Nn = 62 isotones is approximately monotonous due to the finiteness of nuclear system.

关键词： nuclear shape phase transition interacting boson model effective order parameter finite particle number effect transition trajectory

X-ray flares of γ-ray bursts: Quakes of solid quark stars?

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Science china(Physics,Mechanics & Astronomy) 2009年第2期52卷 315-320页

作者： XU RenXin1 & LIANG EnWei2 1 school of Physics and State Key laboratory of nuclear Physics and {3., peking university, beijing 100871, china 2 Department of Physics, Guangxi university, Nanning 53.004, china school of Physics and State Key laboratory of nuclear Physics and {3. Peking University Beijing China Department of Physics Guangxi University Nanning China

A star-quake model is proposed to understand X-ray flares of both long and short γ-ray bursts (GRBs) in a solid quark star regime. Two kinds of central engines for GRBs are available if pulsar-like stars are actually (solid) quark stars, i.e., the SNE-type GRBs and the SGR-type GRBs. It is found that a quark star could be solidified about 103.to 106 s later after its birth if the critical temperature of phase transi- tion is a few Metga-electron-volts, and then a new source of free energy (i.e., elastic and gravitational ones, rather than rotational or magnetic energy) could be possible to power GRB X-ray flares.

关键词： γ-rays bursts: X-rays neutron stars elementary particles

Zircon and apatite fission track analyses on mineralization ages and tectonic activities of Tuwu-Yandong porphyry copper deposit in northern Xinjiang, china

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Science china Earth Sciences 2007年第12期50卷 1787-1795页

作者： YUAN WanMing1,BAO ZengKuan2,DONG JinQuan2,GUO ZhaoJie3.& DENG Jun1 1 State Key laboratory of Geological Processes and Mineral Resources,china university of Geosciences,{3.100083.china 2 laboratory of nuclear Analysis Techniques,Institute of High Energy Physics,Chinese Academy of Sciences,{3. 10003.,china 3.Department of Geology,peking university,{3. 100871,china State Key laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China laboratory of nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China Department of Geology Peking University Beijing China

The mineralization ages reported in the past in the Tuwu-Yandong copper district not only are different,but also fall into the Hercynian *** study has achieved 9 zircon and 7 apatite fission track analysis *** zircon fission track ages range from 158 Ma to 289 Ma and the apatite ages are between 64 Ma and 140 *** mineralization accords with the regional tectonics in the copper *** consider that the zircon fission track age could reveal the mineralization age based on annealing zone temperature of 140―3.0℃ and retention temperature of ～250℃ for zircon fission track,and metallogenetic temperature of 120―3.0℃ in this ore *** three mineralization epochs have been identified,i.e.,289―276 Ma,23.―200 Ma and 165―158 Ma,and indicate occurrence of the min-eralization in the Indosinian and Yanshan *** to apatite fission track ages,the three tectonic-mineralizing epochs are 140―13. Ma,109―97 Ma and 64 Ma,which means age at about 100℃ after the *** three epochs lasted 146 Ma,108 Ma and about 100 Ma from ～250℃ to ～100℃ and trend decrease from early to *** is shown by the fission track modeling that this district underwent three stages of geological thermal histories,stable in Cretaceous and cooling both before Cretaceous and after 20 Ma.

关键词： mineralization age, tectonic epoch, fission track, zircon, apatite, Tuwu-Yandong, Xinjiang

Properties of the 3.2^-[521] band in the odd-N rare-earth nuclei

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 37-43页

作者： CHEN Liang1,2, ZHOU XiaoHong1,2, ZHANG YuHu1, ZHANG ShuangQuan3.& ZHU LiHua4 1Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 73.000, china 2Graduate university of Chinese Academy of Sciences, beijing 100049, china 3.tate Key laboratory of nuclear Physics and technology, school of Physics, peking university, beijing 100871, china 4china Institute of Atomic Energy, beijing 102413. china Institute of Modern Physics Chinese Academy of Sciences Lanzhou China Graduate university of Chinese Academy of Sciences Beijing China State Key laboratory of nuclear Physics and technology School of Physics Peking University Beijing China china Institute of Atomic Energy Beijing China

High-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2+[642], 3.2-[521], and 11/2-[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2 branch of the ground state 3.2-[521] band has been revised significantly. It is found that signature inversion occurs in the 3.2-[521] band after the band crossing in 161Er. The systematics of the signature inversion associated with the 3.2-[521] configuration in the rare-earth region is discussed. The band properties are analyzed within the framework of a triaxial particle-rotor model, and a triaxial deformation is proposed to the 3.2-[521] band.

关键词： high-spin states signature inversion triaxial particle-rotor model

A template of rat brain based on fMRI T2* imaging

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Progress in Natural Science:Materials International 2005年第6期15卷 502-506页

作者： HU Zhenghui1, WU Yigen2, WANG Xiaochuan3. WANG Jianzhi3. CHEN Feiyan1 and TANG Xiaowei1*(1. Department of Physics and Bio-X laboratory, Zhejiang university, Hangzhou 3.0027, china 2. Institute of High Energy Physics and Key laboratory of nuclear Analysis Techniques, Chinese Academy of Sciences,beijing 10003., china 3. Department of Pathophysiology, Tongji Medical College, Huazhong university of Science and technology, Wuhan 43.03., china) Department of Physics and Bio-X laboratory Zhejiang University Hangzhou 310027 China Key laboratory of nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China Department of Pathophysiology Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

The development of functional magnetic resonance imaging (fMRI) technology has made it possible to carry out functional brain imaging experiments in small animals. Usually, group data is required to form the assessment of population, which can not only increase the sensitivity of the overall experiment, but also allow the generalization of the conclusion to the whole population. In order to average the signals of functional brain images from different subjects, it is necessary to put all the mapping images into the same standard space (template image). However, up to now, most animal brain templates remain unavailable and it must be done by ourselves. In this study, a template image based on the brains of eight male Wistar rats is obtained, and it is successfully used in our present Alzheimer disease (AD)-like rat model studies as template for spatially normalizing images to the same stereotaxical space. The fMRI results processed with statistical parametric mapping (SPM99) software are in agreement with the results from immunohistochemical experiment, which proves that this method is universally applicable to the pathologic models of other small animals and to human brain lesion studies.

关键词： fMRI animal model atlas template normalization T*2.

Exotic structure of the third excited state in^(21)Na

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Chinese Science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2,3. LIANG Yujie1,2,3. DENG Fuguo1,2,3. LIU Zuhua1,4 & ZHOU Hongyu1,2,3.1. Key laboratory of Beam technology and Material Modification of Minister of Education, beijing Normal {3., beijing 100875, china 2. Institute of Low Energy nuclear Physics, and Department of Material Science and Engineering, beijing Normal {3., beijing 100875, china 3. beijing Radiation Center, beijing 100875, china 4. china Institute of Atomic Energy, beijing 102413. china Key laboratory of Beam technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China Institute of Low Energy nuclear Physics Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2= of the third excited state in 21Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73. and 1/2=5.28 fm respectively. The P value and the contribution of the asymptotic part to the 1/2 are compared with those of several other low energy states in 21Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 20Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 21Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

Effects of nitrogen ion implantation on Ca^(2+) concentration and membrane potential of pollen cell

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Chinese Science Bulletin 2001年第20期46卷 1691-1693页

作者： HUANG Zhonglian, JING Yanping, ZHU Guoli, LU Ting, ZHOU Hongyu & REN Haiyun1. Key laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, beijing Normal university, beijing 100875, china 2. Key laboratory of Plant Physiology and Biochemistry of the Ministry of Agriculture, china Agriculture university, beijing 100094, china 3. Institution of Low Energy nuclear Physics, beijing Normal university, beijing 100875, china Key laboratory of Cell Proliferation Regulation Biology of Min. of Educ. Beijing Normal University Beijing 100875 China

The effects of low energy nitrogen ion implantation on Ca2+ concentration and membrane potential of illy (Mum davidii Duch) pollen cell have been studied. The results showed that the Ca2+ concentration was increased when pollen grain was implanted by nitrogen ion with energy 100 keV and dose 1013.ions/cm2. However, the increase of Ca2+ concentration was partly inhibited by the addition of Ca2+ channel inhibitor depending on dose. And nitrogen ion implantation caused depolarization of pollen cell membrane potential. In other words, membrane potential was increased, but the effect decreased by adding Ca2+ channel inhibitor. However, it was still significantly higher than the membrane potential of control cells. It was indicated that the depolarization of cell membrane potential opened the calcium channel on the membrane that caused the increasing of intracel-lular calcium concentration. This might be an earlier step of the effect of low energy nitrogen ion implantation on pollen germination.

关键词： nitrogen ion implantation lily pollen calcium concentration membrane potential.

Magnetic moments of ^(3.)Mg in the time-odd relativistic mean field approach

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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 {3.,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 3.Mg with effective interaction *** ground state of 3.Mg has been found to be prolate deformed,β2=0.23.with the odd neutron in 1/2[3.0] orbital and the energy -251.85 MeV which is close to the data -252.06 *** magnetic moment -0.913. 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