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β-delayed proton decays near the proton drip line

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Science China(physics,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2 , CHEN Yongshou 2 , XU Furong 3., WANG Kun 4 , PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. institute of Modern physics, Chinese Academy of Sciences, Lanzhou 73.000, China 2. Nuclear physics Department, China institute of Atomic energy, beijing 102413. China 3. Department of Technical physics, Peking University, beijing 100871, China 4. Shanghai institute for Nuclear Research, Shanghai 201800, China 1. institute of Modern physics Chinese Academy of Sciences 730000 Lanzhou China 2. Nuclear physics Department China Institute of Atomic Energy 102413 Beijing China 3. Department of Technical physics Peking University 100871 Beijing China 4. Shanghai institute for Nuclear Research 201800 Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2004, namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14 nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92Rh as well as the predicted “waiting point” nuclei 89Ru and 93.d are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2) The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 142Ho and 128Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3. The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

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 1. institute of Modern physics Chinese Academy of Sciences Lanzhou 730000 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. State Key Laboratory of Nuclear Physics and Technology School of Physics Peking University Beijing 100871 China4. China Institute of Atomic Energy Beijing 102413 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

Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science China Earth Sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2,3.1. National Marine Environmental Forecasting Center, beijing 100081, China 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, institute of Atmospheric physics, Chinese Academy of Sciences, beijing 100029, China 3. Graduate University of Chinese Academy of Sciences, beijing 100049, China 1. National Marine Environmental Forecasting Center Beijing 100081 China 2. Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

ABUNDANCE PATTERNS OF REFRACTORY SIDEROPHILE ELEMENTS OF FE-NI METALLIC GRAINS IN C3. CHONDRITES

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Science in China,Ser.B 1986年第3期29卷 326-336页

作者：柴之芳 institute of high energy {3. Academia Sinica beijing

A lot of Fe-Ni metallic grgins in the inclusions from the Allende and Leoville chondrites were studied on the concentration patterns of some refractory siderophile elements, Os, Ir, Ru, Re, W, Mo and Pt, using neutron activation analysis. Our experimental results show that the grains studied in this work can be roughly classified into two types: equilibrium and non-equilibrium grains. This probably reflects their distinction in the fractionation and condensation processes of the solar system. Or the so-called non-equilibrium grains might be the relics from the supernovae *** experiments were carried out on microgram level.

关键词： Ru ABUNDANCE PATTERNS OF REFRACTORY SIDEROPHILE ELEMENTS OF FE-NI METALLIC GRAINS IN C3. CHONDRITES Re Pt ppm work SRM

Nucleon Form Factors and N-A Transitions in a Hypercentral Constituent Quark Model with Meson Cloud

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Communications in Theoretical physics 2007年第3期 539-546页

作者： CHEN Dina-Yong~(1,2) DONG Yu-Bing~(1,+)1 institute of high energy {3.,the Chinese Academy of Sciences,beijing 100049,China2 Graduate School of the Chinese Academy of Sciences,beijing 100049,China institute of high energy {3.，the Chinese Academy of Sciences，beijing 100049，China Graduate School of the Chinese Academy of Sciences，beijing 100049，China institute of high energy {3.，the Chinese Academy of Sciences，beijing 100049，China

We study the nucleon form factors and the nucleon-△(123.)transitions in a framework of hypercentralconstituent quark *** pion meson cloud effect is taken into account *** results show that the pioncloud contributes substantially to the nucleon form factors as well as to the helicity amplitudes of △(123.),and it givesan improved agreement compared to the experimental measurement.

关键词： electromagnetic form factor nucleon and △(123.) hypercentral constituent quark model meson cloud

Fuzzy cluster analysis of the provenance of ancient Yaozhou porcelain body

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Chinese Science Bulletin 2003年第1期48卷 27-30页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2, XIE Jianzhong1, FENG Songlin3. FAN Dongyu3. ZHANG Ying3. CAI Zhifang3. ZHUO Zhenxi4 & GAO Zhengyao1 1. Faculty of Physical Engineering, Zhengzhou University, Zhengzhou 450052, China 2. Department of physics, beijing Normal University, beijing 100875, China 3. {3. energy physics institute, the Chinese Academy of Sciences, beijing 100080, China 4. Archaeology Research institute, Shanxi Province, Xian 710000, China Correspondence should be addressed to Li Guoxia (e-mail: Liguoxia@ ***) Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China Department of physics Beijing Normal University Beijing 100875 China high energy physics {3. Chinese Academy of Sciences Beijing 100080 China Archaeology Research institute Shanxi Province Xi'an 710000 China

The technique of neutron activation analysis (NAA) has been employed to measure the content of 29 kinds of elements in the sample of Yaozhou porcelain bodies. Then a fuzzy cluster analysis has been conducted to the NAA data and a diagram of the dynamic fuzzy cluster analysis has been achieved. The results indicate that the batch of ancient Yaozhou porcelain bodies, which were of different overglaze color and were produced by different kilns during a period of over 800 years from the Tang Dynasty (618—907 A.D.) to the Yuan Dynasty (1271—13.8 A.D.), has shared a stable and concentrated raw material source. Provenances of por-celain bodies from different times, though having their spe-cific independence, enjoy a close relationship and are not far from one another. Provenances of porcelain bodies made during the Tang Dynasty and the Five Dynasties (907—960 A.D.) are found to be closer to one another, while those of the Song (960—1279 A.D.) and the Jin Dynasty (1115—123. A.D.) are comparatively concentrated in certain areas and are dif-ferent from those of the Tang Dynasty. Both the tri-colored glazed pottery made in Yaozhou kilns during the Tang Dy-nasty and the Yaozhou porcelain bodies of the Tang period are from the same provenance.

关键词：古代姚州瓷胎窑址粘土矿原料来源中子活化分布模糊聚类分析

Timing in the Time Domain: Cygnus X-1

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Chinese Journal of Astronomy and Astrophysics 2001年第4期1卷 313-332页

作者： Ti-Pei Li (Department of physics and Center for Astrophysics, Tsinghua University, beijing 100084 {3. energy Astrophysics Lab., institute of {3. energy physics, Chinese Academy of Sciences, beijing 10003.)E-mail:litp@*** Department of physics and Center for Astrophysics Tsinghua University Beijing 100084 High Energy Astrophysics Lab. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039

Quantities characterizing temporal property, e.g., power density, coherence, and time lag, can be defined and calculated directly in the time domain without using the Fourier transformation. Spectral hardness, variability duration, and correlation between different characteristic quamtities on different time scale can be studied in the time domain as well. The temporal analysis technique in the time domain is a powerful tool, particularly in studying rapid variability on short time scales (or in high frequencies). Results of studying variabilities of X-rays from Cyg X-1 with the analysis technique in the time domain and RXTE data reveal valuable clues to understanding production and propagation processes of X-rays and structure of accretion disk in the black hole system.

关键词： methods: data analysis - stars: individual (Cygnus X-1) - X-rays: stars

Temporal study of GRS 1915+105 with rms-flux relation:The importance of magnetic activities in the corona

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Science China(physics,Mechanics & Astronomy) 2010年第S1期53卷 120-124页

作者： HAN Dong1,ZHANG ShuangNan2 & SONG LiMing2 1 Department of Engineering physics & Center for Astrophysics,Tsinghua University,beijing 100084,China 2 Key Laboratory of Particle Astrophysics,institute of high energy physics,Chinese Academy of Sciences,beijing 100049,China 1. Department of Engineering physics & Center for Astrophysics Tsinghua University Beijing 100084 China 2. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

The rms-flux relations for some observations of GRS 1915+105 are *** rms-flux relations of the light curves in only one state,state C or state A,can be described by the simple non-linear model provided Zhang;we thus interpret that such a linear relation reflects the relative importance of magnetic instability for X-ray emission in the corona of the system,compared to the thermal viscous instability for the X-ray emission in the accretion *** rms-flux relations for state B are very scattered,possibly because of the dominance of thermal viscous instability for the X-ray emission in the accretion *** complex rms-flux relations for the observations of transitions between two or three states are caused by the combination of the different rms-flux relations of these *** underlying physical processes are the combination of magnetic topology in the corona and thermal viscous instability in the accretion disk.

关键词： rms-flux relation data analysis GRS 1915+105 magnetic instability

An efficient chiral synthesis of (R)-N-[3.acetyl-4-(2-hydroxy-3.isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science China Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2 & TANG XinLiang1,3.1 Technical institute of physics and Chemistry,Chinese Academy of Sciences,beijing 100080,China 2 College of Chemistry and Chemical Engineering,Graduate University of Chinese Academy of Sciences,beijing 100049,China 3.School of Chemical Engineering and Environment,beijing institute of Technology,beijing 100081,China 1. Technical institute of physics and Chemistry Chinese Academy of Sciences Beijing 100080 China 2. College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. School of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China

R-Enantiomer of the β-receptor antagonist N-[3.acetyl-4-(2-hydroxy-3.isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13. NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis