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Criterion for reducible hydrodynamic equations of baryon-rich quark-gluon plasma

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Nuclear science and Techniques 2000年第1期11卷 41-44页

作者： AI Xiao-Bai (Hsiao-bat AI) (center of theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000 Shanghai Institule of Nuclear Research, the chinese academy of sciences, Shanghai 201800) 兰州原子核理论研究中心重离子加速器国家实验室甘肃兰州 730000

Besides the state equation there exists another cubic algebraic equation about μf in the form of μf3 + pμf + q = 0, which relates parameters, temperature T, chemical potential μf, and net quark number nff （flavor f） for a baryon-rich quark-gluon plasma （QGP）. A criterion may be acquired simply according to Cardan formula of the solution of the above equation, which gives naturally a condition: if n 2πT3/3, one may approximately use the conservation of specific entropy, and then the set of hydrodynamic equation of baryon-rich QGP may be reduced to the set of hydrodynamic equation for baryon-free QGP.

关键词：重子夸克胶子粒子物理学简化流体动力学方程等离子体 QGP

Analysis on the decadal scale variation of the dust storm in North china

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science china Earth sciences 2005年第12期48卷 2260-2266页

作者： KANG Dujuan1,2 & WANG Huijun1 1. NZC/LASG, Institute of Atmospheric physics, chinese academy of sciences, beijing 100871, china 2. Environmental Fluid Mechanics Laboratory, Stanford University, Stanford CA 94305, USA 1. NZC/LASG Institute of Atmospheric Physics Chinese Academy of Sciences 100871 Beijing China 2. Environmental Fluid Mechanics Laboratory Stanford University 94305 Stanford CA USA

In this paper, the temporal variation characteristics of the dust storm in North china are investigated. Based on power spectrum analysis and wavelet analysis, 1956-1970 and 1985-1999 are chosen as the high-frequency and low-frequency dust storm decades respectively. Analysis results clearly show that the spring and wintertime anomalous atmospheric circulation between these two dec-ades are significantly different. Compared with the former decade, there are a strengthened polar vortex, enhanced westerlies near 50°N, and a weak East Asian major though in the winter of the latter decade. The north and center parts of the Siberian high and the Aleutian low become weak. The southerly and easterly wind anomalies appear over the north and east parts of china, which implies the weakening of East Asian winter monsoon. Meanwhile, northern china experiences warmer winters and wetter springs, which are in favor of the weakening of dust storm intensity in North china. There are significant out-of-phase relationships between dust frequency and wintertime westerly intensity, as well as between dust frequency and Arctic Oscillation. It is also found that the frequency of dust weather is strongly re-lated to winter-springtime East Asian monsoon intensity.

关键词： dust storm, climate anomaly, decadal scale variability, East Asian monsoon, AO.

Half-lives and fine structure for the α decay of deformed even-even nuclei

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science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 24-31页

作者： NI DongDong1,2 & REN ZhongZhou1,2,3 1Department of physics, Nanjing University, Nanjing 210093, china 2Kavli Institute for theoretical physics china, beijing 100190, china 3center of theoretical Nuclear physics, National Laboratory of Heavy-Ion Accelerator, Lanzhou 730000, china Nanjing Univ Dept Phys Nanjing 210093 Jiangsu Peoples R China Kavli Inst Theoret Phys china Beijing 100190 Peoples R China Ctr Theoret Nucl Phys Natl Lab Heavy Ion Accelerator Lanzhou 730000 Peoples R China

The α-decay properties of well-deformed even-even nuclei are systematically calculated within the multichannel cluster model (MCCM). Instead of working in the WKB framework, the quasibound solution to the coupled Schro¨dinger equation is presented with outgoing wave boundary conditions, and the coupling potential is taken into full account in terms of the general quantum theories. The calculated α-decay half-lives are found to agree well with the experimental data with a mean factor of less than 2. The fine structure observed in α decay is also well reproduced by the four-channel microscopic calculation. Very strikingly, the MCCM can give relatively precise descriptions of the branching ratio to excited 4+ states, which is often overestimated in the usual WKB calculations. We expect it to be a significant development of theoretical models toward quantitative descriptions of α transitions to high-spin daughter states.

关键词： α decay half-lives cluster model coupled channel approach

Statistical study of the pulse width distribution for radio pulsars

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science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 220-223页

作者： CHEN JianLing1,2,WANG Na1,YUAN JianPing1,2,WANG HongGuang3,YAN WenMing1,2 & LIU ZhiYong1 1 Urumqi Observatory,National Astronomical Obsevatories,chinese academy of sciences,Urumqi 830011,china 2 Graduate University of the chinese academy of sciences,beijing 100049,china 3 center for Astrophysics,Guangzhou University,Guangzhou 510006,china 1. Urumqi Observatory National Astronomical Obsevatories Chinese Academy of Sciences Urumqi 830011 China 2. Graduate University of the chinese academy of sciences Beijing 100049 China 3. center for Astrophysics Guangzhou University Guangzhou 510006 China

Pulse widths of standard pulse profiles for 262 pulsars were measured by using the Urumqi 25 m radio telescope at 1.54 *** the simplest case of circular emission beam,we applied Monte Carlo simulations to the pulse width *** density functions of magnetic inclination angle α and observer angle ξ were *** Kolmogorov-Smirnov tests,we derived the most probable distribution for α and ξ.

关键词： pulsar pulse width emission beam random distribution

π~±Elastic Scattering and Excitation Function of Pion SCX Reaction on ^(13)C

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chinese journal of nuclear physics 1997年第3期19卷 142-146页

作者： Ren Yongjian~(1,2) Gu Jianzhong~1) Lei Yian~1) Zeng Guomo~(1,3)1)Institute of theoretical physics,the chinese academy of sciences,P.O.Box 2735,beijing 1000802)Teaching and Research Section of physics,Agriculture University of china,beijing 1000833)Department of physics,Jiliu University,Changchun 130023 中科院理论物理所北京

The elastic scattering of 162 MeV л± from 13C and the excitation function of 13C（л+,л0）13N are analyzed in the frame of the Glauber *** nuclear wave function is assumedto be constructed by a valence nucleon plus a core of 12C which is described by an independent αcluster model.A good agreement between the theory and experiment is obtained.

关键词： Glauber theory α cluster model Scattering cross section Excitation function

Distinguished Effects of Interannual Salinity Variability on the Development of the Central-Pacific El Ni o Events

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Atmospheric and Oceanic science Letters 2012年第2期5卷 123-127页

作者： ZHENG Fei 1,WAN Li-Ying 2,and WANG Hui 3 1 International center for Climate and Environment science (ICCES),Institute of Atmospheric physics,chinese academy of sciences,beijing 100029,china 2 Key Laboratory of Research on Marine Hazards Forecasting,National Marine Environmental Forecasting center,beijing 100081,china 3 National Meteorological center,beijing 100081,china [a] International center for Climate and Environment science (ICCES) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China[b] Key Laboratory of Research on Marine Hazards Forecasting National Marine Environmental Forecasting Center Beijing 100081 China[c] National Meteorological Center Beijing 100081 China

El Nio events in the central equatorial Pacific (CP) are gaining increased attention,due to their increasing intensity within the global warming *** physical processes have been identified in the climate system that can be responsible for the modulation of El Nio,especially the effects of interannual salinity *** this work,a comprehensive data analysis is performed to illustrate the effects of interannual salinity variability using surface and subsurface salinity fields from the Met Office ENSEMBLES (EN3) quality controlled ocean *** is demonstrated that during the developing phase of an El Nio event,a negative sea surface salinity (SSS) anomaly in the western-central basin acts to freshen the mixed layer (ML),decrease oceanic density in the upper ocean,and stabilize the upper *** related oceanic processes tend to reduce the vertical mixing and entrainment of subsurface water at the base of the ML,which further enhances the warm sea surface temperature (SST) anomalies associated with the El Nio ***,the effects of interannually variable salinity are much more significant during the CP-El Nio than during the eastern Pacific (EP) El Nio,indicating that the salinity effect might be an important contributor to the development of CP-El Nio events.

关键词： salinity effect CP-E1 Nifio EN3 dataset

Synthesis of superheavy nuclei with ^(238)U target

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science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1482-1488页

作者： LIU ZuHua1,3 & BAO JingDong2,4 1 Key Laboratory of Beam Technology and Material Modification of Ministry of Education,beijing Normal University,beijing 100875,china 2 Department of physics,beijing Normal University,beijing 100875,china 3 china Institute of Atomic Energy,beijing 102413,china 4 center of theoretical Nuclear physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,china Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China Department of physics Beijing Normal University Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China center of theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The production of superheavy nuclei with Z=108-116 via hot fusion reactions of the neutron-rich projectiles with 238U target is systematically *** results show that the production cross sections of superheavy nuclei do not decrease monotonously as the atomic number Z *** cross sections of the superheavy nuclei at Z = 112 and 115 are enhanced as compared with the whole Z-trend in synthesis of the superheavy nuclei,which clearly illustrates that the reactions with large negative Q-value and shell correction are more favorable to synthesize superheavy nuclei.

关键词： superheavy nuclei fusion reaction cross section 238U target

Preconditioners for higher order edge finite element discretizations of Maxwell's equations

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science china Mathematics 2008年第8期51卷 1537-1548页

作者： ZHONG LiuQiang1,2,SHU Shi1,2,SUN DuDu3&TAN Lin4 1School of Mathematical and Computational sciences,Xiangtan University,Xiangtan 411105,china 2Hunan Key Laboratory for Computation and Simulation in science and Engineering,Xiangtan 411105,china 3Institute of Computational Mathematics and Scientific/Engineering Computing,academy of Mathematicsand Systems science,Graduate University of chinese academy of sciences,chinese academy sciences,P.O.Box 2719,beijing 100190,china 4Department of Math-physics,Nanhua University,Hengyang 421001,china 1. School of Mathematical and Computational sciences Xiangtan University Xiangtan 411105 China 2. Hunan Key Laboratory for Computation and Simulation in science and Engineering Xiangtan 411105 China 3. Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Graduate University of Chinese Academy of Sciences Chinese Academy Sciences P.O. Box 2719 Beijing 100190 China 4. Department of Math-physics Nanhua University Hengyang 421001 China

In this paper,we are concerned with the fast solvers for higher order edge finite element discretizations of Maxwell's *** present the preconditioners for the first family and second family of higher order N′ed′elec element equations,*** combining the stable decompositions of two kinds of edge finite element spaces with the abstract theory of auxiliary space preconditioning,we prove that the corresponding condition numbers of our preconditioners are uniformly bounded on quasi-uniform *** also present some numerical experiments to demonstrate the theoretical results.

关键词： preconditioner higher order edge finite element stable decomposition

Dynamics of DNA in vitro evolution

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Progress in Natural science:Materials International 2009年第2期19卷 137-144页

作者： Xiaojing Yang 1,Xili Liu 1,Chunbo Lou,Qi Ouyang center for theoretical Biology,School of physics,Peking University,beijing 100871,china [a]center for theoretical Biology School of Physics Peking University Beijing 100871 China

In vitro evolution has become a very important research area in recent years. From a practical point of view,it provides a powerful and reliable tool for engineering functional molecules (DNA,RNA or proteins) in reasonably short periods of time. From a theoretical point of view,since in vitro evolution is analogous to natural evolution in many respects,the study of the dynamic details of in vitro evolution may provide some instructive insights into the process of evolution. In this review,we summarize current theoretical and exper-imental studies,including several efforts made by our group,on the dynamics of DNA in vitro evolution.

关键词： DNA-TF interaction DNA in vitro evolution Natural evolution Crossover