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Systematic study of survival probability of excited superheavy nuclei

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science china({2.,Mechanics & Astronomy) 2011年第S1期54卷 109-113页

作者： XIA ChengJun1, SUN BaoXi1, ZHAO EnGuang2.3.& ZHOU ShanGui2.3.1College of Applied sciences, {3. University of Technology, {3. 10012., china 2.nstitute of Theoretical physics, chinese Academy of sciences, {3. 100190, china 3.14} of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 73.000, china chinese Acad Sci Inst Theoret Phys Beijing 100190 Peoples R China beijing Univ Technol Coll Appl Sci Beijing 100124 Peoples R China Ctr Theoret Nucl Phys Natl Lab Heavy Ion Accelerator Lanzhou 730000 Peoples R China

The stability of excited superheavy nuclei (SHN) with 100 Z 13. against neutron emission and fission is investigated by using a statistical model. In particular, a systematic study of the survival probability against fission in the 1n-channel of these SHN is made. The present calculations consistently take the neutron separation energies and shell correction energies from the calculated results of the finite range droplet model which predicts an island of stability of SHN around Z = 115 and N = 179. It turns out that this island of stability persists for excited SHN in the sense that the calculated survival probabilities in the 1n-channel of excited SHN at the optimal excitation energy are maximized around Z = 115 and N = 179. This indicates that the survival probability in the 1n-channel is mainly determined by the nuclear shell effects.

关键词： survival probability superheavy elements island of stability neutron emission fission

Molecular dynamics simulation of kink in 〈100〉 edge dislocation in body centred cubic iron

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chinese science Bulletin 2007年第16期52卷 2291-2296页

作者： CHEN LiQun1,2.WANG ChongYu2.3.4 & YU Tao2.1 College of {3.s,Central South University of Forestry & Technology,Changsha 410004,china 2.Central Iron and Steel Research Institute,{2. 100081,china 3.Department of physics,Tsinghua University,{2. 100084,china 4 International center for Materials physics,{13. Academy of {3.s,Shenyang 110016,china College of sciences Central South University of Forestry and Technology Changsha 410004 China

Using the molecular dynamics method,we have constructed two kink models corresponding to the 〈100〉{010} and 〈100〉{011} edge dislocations (EDs) in body centred cubic (bcc) Fe. It is found that the geometric structure of a kink depends on the type of edge dislocation and the structural energies of the atoms sites in the dislocation core region. The formation energies,migration energies and widths of the kinks in different types of EDs are calculated. The results show that formation and migration of the kink in the 〈100〉{010} edge dislocation are difficult. The 〈100〉{011} edge dislocation moves primarily through kink nucleation,rather than kink migration.

关键词：分子动力学边缘位移铁纽结结构

Some evidence of drying trend over northern china from 1951 to 2.04

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chinese science Bulletin 2006年第23期51卷 2913-2925页

作者： MA Zhuguo1,2.& FU Congbin1,2.1. Key Laboratory of Regional Climate-Environment for Temperate East Asia, chinese Academy of {3.s, {2. 10002., china 2. START Regional center for Temperate East Asia, Institute of Atmos-pheric physics, chinese Academy of {3.s, {2. 10002., china Key Laboratory of Regional Climate-Environment for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China START Regional center for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The surface wetness index, Palmer drought sererity index and the retrieval of soil moisture over china were calculated using monthly precipitation and monthly mean surface air temperature. Based on the contrast analysis of the variation of the above three indices and precipitation, the dry/wet spatio-temporal pattern of northern china in the last 54 years was revealed, and the evidence of drying trend over northern china was analyzed, especially. The results show the following four facts: (1) The drying trend is the main characteristic of the eastern part of Northwest china and the central part of North china since the 1980s and it was enhanced in the last 15 years mainly due to the precipitation decrease and the temperature increase; (2. During the last 54 years, there was only one dry/wet shift at the interdecadal scale occurring in the eastern part of Northwest china and the central part of North china in the late 1970s, which was related to 1977/1978 global abrupt change, whereas there were three shifts in Northeast china, one was in the mid 1990s and the other two were in 1965 and 1983. respectively; (3. Unlike the variation trend of other subregions of northern china, the western part of Northwest china is currently located in a relatively wetting period, which is weak-ened due to the temperature increase; (4) The extreme drought frequency is obviously increasing in the eastern part of Northwest china, the central part of North china and Northeast china since the 1980s, which is closely related to the precipitation decrease and temperature increase in these subregions.

关键词：中国北方干燥趋向干旱索引气候背景

The onset and advance of the Asian summer monsoon

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science Bulletin 2006年第1期51卷 80-88页

作者： Lü Junmei1,2.4, ZHANG Qingyun1, TAO Shiyan1 & JU Jianhua3.1. State Key Laboratory of Numerical Modeling for Atmospheric Sci- ences and Geophysical Fluid Dynamics, Institute of Atmospheric physics, chinese Academy of {2.s, beijing 10002., china 2. Department of Atmospheric {2.s, Yunnan University, Kunming 650091, china 3. china Meteorological Administration Training Centre, beijing 100081, china 4. Graduate School of chinese Academy of {2.s, beijing 10003., china State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric sciences Yunnan University Kunming 650091 China Graduate School of chinese Academy of sciences Beijing 100039 China china Meteorological Administration Training Centre Beijing 100081 China

Based on the daily outgoing longwave radiation (OLR) data from National Oceanic and At- mospheric Administration (NOAA) satellites, the Cli- mate Prediction center’s merged analysis of pre- cipitation (CMAP) data and the National centers for Environmental Prediction/National center for At- mospheric Research (NCEP/NCAR) reanalysis dataset, the mean intraseasonal variability of the Asian summer monsoon (ASM) is investigated by using power spectrum analysis, band-pass filter, and diagnostic analyses. The processes of the onset and advance of monsoon over the southern part of Indo- {3. Peninsula, the east coast of Bay of Bengal, the South {3. Sea and the Indian subcontinent are explored. It is found that there is an abrupt change in OLR, precipitation and zonal wind during the onset and advance of the ASM. It is also indicated that the southern part of Indo{3. Peninsula and the adja- cent Andaman Sea is the region where the earliest onset of the ASM occurs in the 2.d pentad of May.

关键词： Asian summer monsoon intraseasonal variability onset advance.

Archean relic body at lower crust in Sulu area:Evidence from magnetic data

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chinese science Bulletin 2003年第6期48卷 589-593页

作者： WU Qifan1,2. LU Fengxiang3. LIU Qingsheng3. ZHENG Jianping3. WANG Maoji2.& WU Wenli4 1. Department of Engineering physics, Tsinghua University, {3. 100084, {2. 2. Aero Geophysical Survey & Remote Sensing center, {3. 100083. {2. 3. {2. University of Geosciences, Wuhan 43.074, {2. 4. Institute of Geophysical & Geochemical Exploration, Langfang 065000, {2. Aero Geophysical Survey & Remote Sensing center Beijing 100083 China china University of Geosciences Wuhan 430074 China Institute of Geophysical & Geochemical Exploration Langfang 065000 China Department of Engineering physics Tsinghua University Beijing 100084 China

After the new 1︰1000000 aero magnetic data were processed and the three-dimensional inversion work was carried out, a vast high magnetic body northwestward was discovered. The magnetic body is located at the depth of about 2. km on the west side of Tanlu fault and at about 2. km on the east side of Tanlu fault beneath the Sulu area. There is a difference of vertical distance of 3.5 km in depth between both sides. We think that the magnetic body is an Archean metamorphic plate and belongs to the North china block. The discovery of the magnetic body is significant for us to reconstruct the structure model of the Sulu orogenic belt, delineate the suture of collision between the North china block and the Yangtze block, and estimate the depth of slipping surface when the eastside of Tanlu fault moved northward.

关键词：苏鲁地区地壳下层太古代残余体地球物理调查区域性磁场三维反演苏鲁造山带郯鲁断裂带大别-苏鲁超高压变质带

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

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science china({2.,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 & {3. 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

Enhancement of magnetism of Zn0.95Co0.05O films by p-type Cu+ doping

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Progress in Natural science:Materials International 2011年第1期21卷 31-35页

作者： Wei-chang HAO~(1,5),Jian-jun LI~2.Huai-zhe XU~3.Jia-ou WANG~4,Tian-min WANG~1 1.center of Materials physics and Chemistry,Beihang University,{2. 100083.china 2.Department of Materials science and Engineering, Anhui University of science and Technology,Huainan 2.2.01,china 3.Department of physics,Beihang University,{2. 100083.china 4.{2. Synchrotron Radiation Facility,Institute of High Energy physics, {12. Academy of sciences,100049,china 5.Key Laboratory of Micro-nano Measurement,Manipulation and physics, Ministry of Education,Beihang University,{2. 100191,china [a] center of Materials physics and Chemistry Beihang University Beijing 100083 China [b] Department of Materials science and Engineering Anhui University of Science and Technology Huainan 232001 China [c] Department of physics Beihang University Beijing 100083 China [d] beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences 100049 China [e] Key Laboratory of Micro-nano Measurement Manipulation and Physics Ministry of Education Beihang University Beijing 100191 China

Zn0.95Co0.05O and Zn0.91Co0.05Cu0.04O thin films were fabricated on Si（111） substrate by the reactive magnetron sputtering method at different O-Ar *** characterizations by X-ray diffractometry（XRD）,X-ray photo-electronic spectrum（XPS）, and electron paramagnetic resonance（EPR） indicate that the doped Cu ions substitute the Zn2.ions in the ZnO *** doped Cu ions are in Cu+and Cu2.mixture valence *** ferromagnetism of the Zn0.91Co0.05Cu0.04O film increases gradually the increasing Cu+ions *** results indicate that the increase of ferromagnetism is not owing to the magnetic contribution of Cu+ions themselves,but owing to the enhancement of magnetic interaction between Co ions,which suggests that p-type doping of Cu+ions plays an important role in mediating the ferromagnetic coupling between Co ions.

关键词： Zn0.95Co0.05O films Zn0.91Co0.05Cu0.04O films magnetic semiconductors magnetic coupling co-doping

Shape phase transitions in nuclei:Effective order parameters and trajectories

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science china({2.,Mechanics & Astronomy) 2011年第S1期54卷 88-97页

作者： ZHANG Yu1,2. HOU ZhanFeng2.& LIU YuXin2.3.1Department of {3., Liaoning Normal University, Dalian 11602., china 2.epartment of {3. and the State Key Laboratory of Nuclear {3. and Technology, Peking University, beijing 100871, china 3.11} of Theoretical Nuclear {3., National Laboratory of Heavy Ion Accelerator, Lanzhou 72.000, china 1. Department of physics Liaoning Normal University Dalian 116029 China2. Department of Physics and the State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China3. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 720000 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. 2. → 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

Pressure-induced crystallite breaking in La_(0.7)Sr_(0.3.Mn_(0.9)Fe_(0.1)O_3.nanosolids

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chinese science Bulletin 1998年第6期43卷 458-461页

作者： ZHENG Fanlei 1, 2. SUI Yu 1, 3. XU Dapeng 1 and SU Wenhui 1, 4 1. Department of physics, Jilin University, Changchun 13.02., {3. 2. Changchun Institute of physics, chinese Academy of sciences, Changchun 13.02., {3. 3. Institute of Metal R Department of physics Jilin University Changchun Chinas Changchun Institute of physics Chinese Academy of Sciences Changchun China Institute of Metal Research Chinese Academy of Sciences Shenyang China International center for Materials physics Chinese Academy of Sceinces Shenyang China center for Condensed Matter and Radiation physics CCAST (World Lab.) Beijing China

In the compacting process of the La 0.7Sr 0.3.n 0.9Fe 0.1O 3.nanosolids under the pressure range of 0.0-4.5 GPa, the apparent pressure-induced crystallite breaking phenomenon in these nanosolids was observed. With increasing pressure up to 4.5 GPa, the average grain size decreases by 46% while the magnetization of nanosolids decrease by 40% and their coercive increases by 3.%. This kind of breaking has a close relation to the existence of oxygen deficiency in La 0.7Sr 0.3.n 0.9Fe 0.1O 3.nanoparticles. A simple and convenient method for preparing the bulk nanosolids with a large number of clean interfaces has been suggested.

关键词： nanosolid pressure-induced breaking high pressure.