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A phenomenological equation of state for isospin asymmetric nuclear matter

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Science china({1.,Mechanics & Astronomy) 2009年第10期52卷 1494-1505页

作者： chen LieWen1.2 1.{1. of physics,shanghai Jiao Tong university,shanghai 200240,china 2 Center of Theoretical Nuclear physics,National Laboratory of Heavy Ion Accelerator,Lanzhou 730000,china department of {1. Shanghai Jiao Tong University Shanghai 200240 China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China

A phenomenological momentum-independent(MID) model is constructed to describe the equation of state(EOS) for isospin asymmetric nuclear matter,especially the density dependence of the nuclear symmetry energy Esym(ρ).This model can reasonably describe the general properties of the EOS for symmetric nuclear matter and the symmetry energy predicted by both the sophisticated isospin and momentum dependent MDI model and the Skyrme-Hartree-Fock *** find that there exists a nicely linear correlation between Ksym and L as well as between J0/K0 and K0,where L and Ksym represent,respectively,the slope and curvature parameters of the symmetry energy at the normal nuclear density ρ0,while K0 and J0 are,respectively,the incompressibility and the third-order derivative parameter of symmetric nuclear matter at ρ*** correlations together with the empirical constraints on K0,L and Esym(ρ0) lead to an estimation of -477 MeV Ksat,2 -241.MeV for the second-order isospin asymmetry expansion coefficient for the incompressibility of asymmetric nuclear matter at the saturation point.

关键词： equation of state of nuclear matter isospin the symmetry energy

Higher order bulk characteristic parameters of asymmetric nuclear matter

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Science china({1.,Mechanics & Astronomy) 2011年第S1期54卷 124-129页

作者： chen LieWen1.2 1.1. of physics, shanghai Jiao Tong university, shanghai 200240, china 2Center of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000, china 1. department of {1. Shanghai Jiao Tong University Shanghai 200240 China 2. Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China

The bulk parameters characterizing the energy of symmetric nuclear matter and the symmetry energy defined at normal nuclear density ρ0 provide important information on the equation of state (EOS) of isospin asymmetric nuclear matter. While significant progress has been made in determining some lower order bulk characteristic parameters, such as the energy E0(ρ0) and incompress ibility K0 of symmetric nuclear matter as well as the symmetry energy Esym(ρ0) and its slope parameter L, yet the higher order bulk characteristic parameters are still poorly known. Here, we analyze the correlations between the lower and higher order bulk char acteristic parameters within the framework of Skyrme Hartree-Fock energy density functional and then estimate the values of some higher order bulk characteristic parameters. In particular, we obtain J0 = (-355±95) MeV and I0 = (1.73±680) MeV for the third order and fourth-order derivative parameters of symmetric nuclear matter at ρ0 and Ksym = (-1.0 ± 1.5) MeV, Jsym = (224 ± 385) MeV, Isym = (-1.09 ± 2025) MeV for the curvature parameter, third-order and fourth-order derivative parameters of the symmetry energy at ρ0, using the empirical constraints on E0(ρ0), K0, Esym(ρ0), L, and the isoscalar and isovector nucleon effective masses. Furthermore, our results indicate that the three parameters E0(ρ0), K0, and J0 can reasonably characterize the EOS of symmetric nuclear matter up to 2ρ0 while the symmetry energy up to 2ρ0 can be well described by Esym(ρ0), L, and Ksym.

关键词： equations of state of nuclear matter forces in hadronic systems and effective interactions symmetry energy nuclear density functional theory and extensions asymmetric matter neutron matter

Anticoagulation property and security of artificial heart valve material

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Science china(Technological Sciences) 2005年第2期48卷 145-162页

作者： WANG Xianghui1, , LIU Xianghuai1,22, 3, ZHANG Feng2, LI Changrong2, YU Liujiang2, zheng Zhihong2, WANG Xi2, JIANG Zhenbin4, chen Anqing4 & XU Jingfang3 1. department of physics, East china normal university, shanghai 200062, china 2. Ion Beam Lab, shanghai Institute of Mini-system and information, Chinese Academy of Sciences,shanghai 200050, china 3. department of Electronics, School of Information Science and Technology, East china normal Univer- sity, shanghai 200062, china 4. shanghai Cardiovascular Institute, Zhongshan Hospital, shanghai 200032, china 1. department of {1. East China Normal University 200062 Shanghai China 2. Ion Beam Lab Shanghai Institute of Mini-system and information Chinese Academy of Sciences 200050 Shanghai China 3. department of Electronics School of Information Science and Technology East China Normal University 200062 Shanghai China 4. shanghai Cardiovascular Institute Zhongshan Hospital 200032 Shanghai China

Heart valve diseases threaten human health. One reliable way to save lives of such patients is to replace the pathologically changed heart valves by artificial ones. Over 2 million patients have received LTI-carbon heart valve’s implantation. However, the thrombosis after the implantation is one of the difficulties that need to be solved. In order to improve the blood compatibility and security of mechanical heart valves, ion beam technology was used to modify the surface properties of the materials. The investigation results have been summarized in this paper.

关键词： artificial heart valve, ion implantation, plasma immersed ion implantation, ion beam enhanced deposition.

X-ray spectra induced by slow highly charged Ar^(q+) ions in collision with Nb surface

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Science china({1.,Mechanics & Astronomy) 2008年第10期51卷 1463-1469页

作者： YANG ZhiHu1, CUI Ying2, chen XiMeng2, SONG ZhangYong1, SHAO JianXiong2, RUAN FangFang1, ZHANG HongQiang2, DU Juan2, LIU YuWen2, GAO ZhiMing2, ZHANG XiaoAn3, zhu KeXin1, YU DeYang1 & CAI XiaoHong1 1 Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 730000, china 2 department of Modern physics, Lanzhou university, Lanzhou 730000, china 3 department of physics, Xianyang normal College, Xianyang 712000, china 1. Institute of Modern physics Chinese Academy of Sciences Lanzhou 730000 China 2. department of Modern {1. Lanzhou University Lanzhou 730000 China 3. department of {1. Xianyang Normal College Xianyang 712000 China

The X-ray spectra of Nb surface induced by Arq+ (q =1.,1.) ions with the energy range from 1. to 20 keV/q were studied by the optical spectrum technology. The experimental results indicate that the multi-electron excitation occurred as a highly charged Ar1.+ ion was neutralized below the metal surface. The K shell electron of Ar1.+ was excited and then de-excited cascadly to emit K X-ray. The intensity of the X-ray emitted from K shell of the hollow Ar atom decreased with the increase of projectile kinetic energy. The intensity of the X-ray emitted from L shell of the target atom Nb increased with the increase of projectile kinetic energy. The X-ray yield of Ar1.+ is three magnitude orders larger than that of Ar1.+.

关键词： highly charged ion hollow atom multi-electron X-ray

Codimension 3 nonresonant bifurcations of homoclinic orbits with two inclination flips

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Science china Mathematics 2005年第2期48卷 248-260页

作者： SHUI Shuliang & zhu Deming College of Mathematics and {1., Zhejiang normal university, Jinhua 321.04, china department of Mathematics, East china normal university, shanghai 200062, china 1. College of Mathematics and physics Zhejiang Normal University 321004 Jinhua China 2. department of Mathematics East China Normal University 200062 Shanghai China

Homoclinic bifurcations in four-dimensional vector fields are investigated by setting up a local coordinate near a homoclinic orbit. This homoclinic orbit is principal but its stable and unstable foliations take inclination flip. The existence, nonexistence, and uniqueness of the 1.homoclinic orbit and 1.periodic orbit are studied. The existence of the two-fold 1.periodic orbit and three-fold 1.-periodic orbit are also obtained. It is indicated that the number of periodic orbits bifurcated from this kind of homoclinic orbits depends heavily on the strength of the inclination flip.

关键词： bifurcation, homoclinic orbit, non-resonance, inclination flip, 1.periodic orbit.

Speciation of the elements and compositions on the surfaces of dust storm particles:The evidence for the coupling of iron with sulfur in aerosol during the long-range transport

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Chinese Science Bulletin 2005年第8期50卷 738-744页

作者： ZHANG Xingying1,2, zhuANG Guoshun1,2,3, chen Jianmin2 & XUE Huaxin2 1. Center for Atmospheric Environment Study, department of Chemistry, Beijing normal university, Beijing 100875, china 2. Center for Atmospheric Chemistry Study, department of Environ- mental Science and Engineering, Fudan university, shanghai 200433, china 3. LAPC/NZC, Institute of Atmospheric physics, NZC/LAPC, Chinese Academy of Sciences, Beijing 100029, china Center for Atmospheric Environment Study Department of Chemistry Beijing Normal University Beijing 100875 China Center for Atmospheric Chemistry Study Department of Environmental Science and Engineering Fudan University Shanghai 200433 China LAPC/NZC Institute of Atmospheric Physics NZC/LAPC Chinese Academy of Sciences Beijing 100029 China

The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in Beijing and Inner Mongolia was studied by XPS. The ma- jor species of iron on the surface were oxides, sulfate, silicate, FeOOH and minor part sorbed on SiO2/Al2O3. Sulfate is the dominant species of sulfur on the surface. SiO2 and Al2O3 are the main components of Si and Al on the surface respectively. One of the most important findings was that the Fe(II) (FeS and FeSO4) produced could account for up to 44.3% and 45.6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 20, 2002, while Fe2(SO4)3, one of the Fe(III) species on the surface decreased from 67.1. to 49.5% and 48.0% respectively. Both S and Fe en- riched on the surface of aerosol particles. Fe(II) accounted for 1.3%?5.3% of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to sup- port the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.

关键词：物种形成原理 XPS 大气悬浮物 Fe-S结合粒子集合

N-Soliron-like Solution of Ito Equation

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Communications in Theoretical physics 2004年第11期 641-644页

作者： ZHANG Yi~(1.2,) chen Deng-Yuan~2 ~1.1. of Mathematics,Zhejiang normal university,Jinhua 321.04,china ~2{1. of Mathematics,shanghai university,shanghai 200436,china department of Mathematics，Zhejiang {1. university，Jinhua 321.04，china department of Mathematics，{1. university，{1. 200436，china department of Mathematics，{1. university，{1. 200436，china

By using the extended Hirota’s method,the N-soliton-like solution of the Ito equation is ***-thermore,we also investSgate the soliton-like solution interaction and find singularity.

关键词： soliton-like solution Ito equation Hirota method

A relative local variational principle for topological pressure

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Science china Mathematics 2010年第6期53卷 1491-1506页

作者： MA XianFeng1,chen ErCai2,3,& ZHANG AiHua2,4 1department of Mathematics,East china university of Science and Technology,shanghai 200237,china 2School of Mathematics and Computer Science,Nanjing normal university,Nanjing 210097,china 3Center of Nonlinear Science,Nanjing university,Nanjing 210093,china 4College of Mathematics and physics,Nanjing university of Posts and Telecommunications,Nanjing 210046,china 1. department of Mathematics East China University of Science and Technology Shanghai 200237 China2. School of Mathematics and Computer Science Nanjing Normal University Nanjing 210097 China3. Center of Nonlinear Science Nanjing University Nanjing 210093 China4. College of Mathematics and Physics Nanjing University of Posts and Telecommunications Nanjing 210046 China

We define the relative local topological pressure for any given factor map and open cover,and prove the relative local variational principle of this *** precisely,for a given factor map π:(X,T)→(Y,S) between two topological dynamical systems,an open cover U of X,a continuous,real-valued function f on X and an S-invariant measure ν on Y,we show that the corresponding relative local pressure P(T,f,U,y) satisfies sup μ∈M(X,T){ hμ(T,U|Y)+∫X f(x)dμ(x) :πμ=ν}=∫Y P(T,f,U,y)dν(y),where M(X,T) denotes the family of all T-invariant measures on ***,the supremum can be attained by a T-invariant measure.

关键词： pressure conditional entropy relative local variational principle

CODIMENSION 3 BIFURCATIONS OFHOMOCLINIC ORBITS WITH ORBITFLIPS AND INCLINATION FLIPS

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Chinese Annals of Mathematics,Series B 2004年第4期25卷 555-566页

作者： SHUISHULIANG zhuDEMING CollegeofMathematicsandphysics ZhejiangNormalUniversityJinhua321004ZhejiangChina. departmentofMathematics EastChinaNormalUniversityShanghai200062China.

The homoclinic bifurcations in four dimensional vector fields are investigated by setting up a local coordinates near the homoclinic orbit. This homoclinic orbit is nonprincipal in the meanings that its positive semi-orbit takes orbit flip and its unstable foliation takes inclination flip. The existence, nonexistence, uniqueness and coexistence of the 1.homoclinic orbit and the 1.periodic orbit are studied. The existence of the twofold periodic orbit and three-fold periodic orbit are also obtained.

关键词： Bifurcation Homoclinic orbit Orbit flip Inclination flip Periodic orbit