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Near infrared lights emission of ^(40)Ar^(16+) impacting on metal surfaces

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Science china(physics,Mechanics & Astronomy) 2009年第7期52卷 1021-1026页

作者： ZHANG XiaoAn1,2, XIAO GuoQing2, YANG ZhiHu2, WANG Li1 & ZHAN WenLong2 1 department of physics, Xianyang Normal university, Xianyang 712000, china 2 Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 730000, china department of physics Xianyang Normal University Xianyang 712000 China Institute of Modern physics Chinese Academy of Sciences Lanzhou 730000 China

The highly charged ion 40Ar16+ with the velocity (kinetic energy EK=150 keV, velocity V=8.5×105 m/s) smaller than Bohr velocity (VBohr=2.9×106 m/s) was found to hove impacts on the surfaces of metals Ni, Mo, Au and Al, and the Ar atomic infrared light lines and X-rays spectra were simultaneously measured. The experimental results show that the highly charged ion that captures electrons is neutralized, and the multiply-excited hollow atom forms. The hollow atom cascade decay radiates lights from infrared to X-ray spectrum. The intensity of infrared lights shows that the metallic work functions play an important role in the neutralization process of highly charged ions during their interaction with metallic surfaces, which verifies the classical over-the-barrier model.

关键词： infrared light lines X-ray neutralization highly charged ions

A computational investigation of boron-doped chromium and chromium clusters by density functional theory

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Science china(physics,Mechanics & Astronomy) 2010年第5期53卷 812-817页

作者： GE GuiXian1,JING Qun1 & LUO YouHua2,3 1 Key Laboratory of Ecophysics and department of physics,Normal College,Shihezi university,Xinjiang 832003,china 2 School of Science,East china university of Science and Technology,Shanghai 200237,china 3 Institute of Theoretical physics,School of physics and Information Optoelectronics,Henan university,Kaifeng 475004,china 1. Key Laboratory of Ecophysics and department of physics Normal College Shihezi University Xinjiang 832003 China2. School of Science East China University of Science and Technology Shanghai 200237 China3. Institute of Theoretical Physics School of Physics and Information Optoelectronics Henan University Kaifeng 475004 China

The geometries,stabilities and electronic properties of Crn and CrnB(n=2-9) clusters have been systematically investigated by density functional *** results suggest that the lowest energy structures for CrnB clusters can be obtained by substituting one Cr atom in Crn+1 clusters with B *** geometries of CrnB clusters are similar to that of Crn+1 clusters except for local structural *** second-order difference and fragmentation energy show Cr4,Cr6,Cr8,Cr3B,Cr5B and Cr8B cluster are the most stable among these studied *** impurity B increases the stabilities of chromium *** B is doped on the Crn clusters,cluster geometry does dominate positive role in enhancing their *** doped B atom does not change the coupling way of the Cr site in Crn clusters,but breaks the symmetry and the Cr atoms are no longer *** doped B atom increases the total magnetic moments of Crn in most cases.

关键词： Crn and CrnB clusters geometries electronic properties

Observations favor the crossing of phantom divide lines

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 562-566页

作者： HUANG TieTie1,2,3, WU PuXun2,3 & YU HongWei2,3 1department of physics, Xiangnan College, Chenzhou 423000, china 2department of physics and Institute of physics, Hunan Normal university, Changsha 410081, china 3Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education, Hunan Normal university, Changsha 410081, china 1. department of physics Xiangnan College Chenzhou 423000 China2. Department of Physics and Institute of Physics Hunan Normal University Changsha 410081 China3. Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education Hunan Normal University Changsha 410081 China

Using three different parameterized dark energy models, we reconstruct the properties of dark energy from the latest 397 Sne Ia, CMB and BAO with the present matter density, Ωm0, given prior. We find that, when Ωm0 is not small, for example, Ωm0 = 0.28 or 0.32, an evolving dark energy with a crossing of phantom divide line is favored and this conclusion seems to be model independent. We also find that the evolving properties of dark energy become more and more evident with the increase of Ωm0 given prior.

关键词： cosmology auelerating expansion dark energy

On SS-quasinormal subgroups and the structure of finite groups

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Science china Mathematics 2011年第3期54卷 449-456页

作者： WEI XianBiao1,2 & GUO XiuYun2, 1department of Mathematics and physics, Anhui Institute of Architecture and Industry, Hefei 230022, china 2department of Mathematics, Shanghai university, Shanghai 200444, china 1. department of Mathematics and physics Anhui Institute of Architecture and Industry Hefei 230022 China2. Department of Mathematics Shanghai University Shanghai 200444 China

A subgroup H of a finite group G is said to be an SS-quasinormal subgroup of G if there is a subgroup B of G such that G = HB and H permutes with every Sylow subgroup of B. In this paper, we investigate the structure of a group under the assumption that every subgroup with order pm of a Sylow p-subgroup P of G is SS-quasinormal in G for a fixed positive integer m. Some interesting results related to the p-nilpotency and supersolvability of a finite group are obtained. For example, we prove that G is p-nilpotent if there is a subgroup D of P with 1 2|D| whenever p = 2 and |D| = 2 is SS-quasinormal in G, where p is the smallest prime dividing the order of G and P is a Sylow p-subgroup of G.

关键词： S-quasinormal subgroups SS-quasinormal subgroups p-nilpotent groups supersolvable groups

X-ray spectra induced in highly charged 40Ar^q+ interacting with Au surface

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 203-212页

作者： ZHANG Xiao’an1,2, XIAO Guoqing1, YANG Zhihu1, CHEN Ximeng3, ZHAO Yongtao1, LI Fuli4, ZHANG Yinping1, CUI Ying3, ZHANG Hongqiang3, XU Xu3, SHAO Jianxiong3 & ZHAN Wenlong11. Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 730000, china 2. department of physics, Xianyang Normal university, Xianyang 712000, china 3. department of Modern physics, Lanzhou university, Lanzhou 730000, china 4. department of Applied physics, Xi’an Jiaotong university, Xi’an 710049, china 1. Institute of Modern physics Chinese Academy of Sciences Lanzhou 730000 China 2. department of physics Xianyang Normal University Xianyang 712000 China 3. department of Modern physics Lanzhou University Lanzhou 730000 China 4. department of Applied physics Xi’an Jiaotong University Xi’an 710049 China

By use of optical spectrum technology, the spectra of X-ray induced by highly charged 40Arq+ ions interacting with Au surface have been studied. The results show that the argon Kα X-ray were emitted from the hollow atoms formed below the surface. There is a process of multi-electron exciting in neutralization of the Ar16+ion, with electronic con-figuration 1s2 in its ground state below the solid surface. The yield of the projectile Kα X-ray is related to its initial electronic configuration, and the yield of the target X-ray is related to the projectile kinetic energy.

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

Effect of rare earths on phase transformation in as-cast ZA27 alloy dur-ing compressive creep

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Rare Metals 2003年第4期22卷 259-264页

作者： WEIXiaowei SHENBaoluo DepamnentofAppliedphysics UniversityofElectronicScienceandTechnologyofChinaChengdu610045China DeparlanentofMetalScience SichuanUniversityChengdu610065China

The effect of the mixed rare earths of Ce on the phase transformation in ascast ZA 27 alloy during compressive was investigated under 37 MPa and at 160 deg C by X-raydiffraction technique and SEM. The results showed that the as cast microstructure of ZA 27-RE alloyconsisted of a dendritic Al-rich alpha' surrounded by Zn-rich beta' phase, interdendritic epsilonphase and Zn-rich eta phase together with a complex Z phase which was a complex constitute compound,(RE,Cu)Al_5Zn_(16), dispersed in crystal interfaces or branch crystal interfaces and stable duringcompressive creep test at 160 deg C. The phase transformations of ZA 27-RE alloy, decomposition ofbeta' phase arid four transformation, were delayed by the addition of rare earths, also the lamellarstructure and the spheroidized structure in ZA 27-RE alloy were finer than in ZA 27 alloy duringcompressive creep test at 160 deg C at the same creep time, and the compressive creep resistance ofZA 27-RE alloy was higher than that of ZA 27 alloy.

关键词： microstructure change compressive creep rare earths ZA 27 alloy

Density functional theory study on the structural and electronic properties of Ag-adsorbed (MgO)_n clusters

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Science china(physics,Mechanics & Astronomy) 2009年第5期52卷 734-741页

作者： GE GuiXian1, JING Qun1 & LUO YouHua2,3 1 Key Laboratory of Ecophysics and department of physics, Normal College, Shihezi university, Shihezi 832003, china 2 School of Science, East china university of Science and Technology, Shanghai 200237, china 3 Institute for Theoretical physics, Henan university, Kaifeng 475004, china Key Laboratory of Ecophysics and department of physics Normal College Shihezi University Shihezi 832003 China School of Science East China University of Science and Technology Shanghai 200237 China Institute for Theoretical physics Henan University Kaifeng 475004 China

Equilibrium geometries, charge distributions, stabilities and electronic properties of the Ag-adsorbed (MgO)n (n = 1-8) clusters have been investigated by density functional theory (DFT) with generalized gradient approximation (GGA) for exchange-correlation functional. The results show that hollow site is energetically preferred for n≥4, and the incoming Ag atoms tend to cluster on the existing Ag cluster. The Mulliken populations indicate that the interaction between the Ag atom and Magnesia clusters is mainly induced by a weak atomic polarization. The adsorbed Ag atom only causes charge redistributions of the atoms near itself. The effect of the adsorbed Ag atom on the bonding natures and structural features of Magnesia clusters is minor. Furthermore, the investigations on the first energy difference, fragmentation energies and electron affinities show that the Ag(MgO)4 and Ag(MgO)6 are the most stable among studied clusters.

关键词： Ag (MgO)_n clusters geometries electronic properties

Application of Fourier Slice Theorem in Wigner Operator Theory and New Complete Representation

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Communications in Theoretical physics 2009年第11期52卷 829-831页

作者： WANG Tong-Tong~1 and FAN Hong-Yi~(2,3)1 School of Mathematics and physics, Huangshi Institute of Technology, Huangshi 435003, china2.department of Material Science and Engineering, university of Science and Technology of china, Hefei 230026, china3 department of physics, Shanghai Jiao Tong university, Shanghai 200030, china School of Mathematics and physics Huangshi Institute of Technology Huangshi 435003 China department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China department of physics Shanghai Jiao Tong University Shanghai 200030 China

By applying the Fourier slice theorem,S;（λ）=∫;P;（t）e;=F（λcosθ,λsinθ）,where P;（t）is aprojection of f（x,p）=（?）F（u,v）e;dudv along lines of constant,to the Wigner operator we are naturally led toa projection operator（pure state）,which results in a new complete *** Weyl orderimg formalism of theWigner operator is used in the derivation.

关键词： Wigner operator Fourier slice theorem new complete representation

Imaging theory of nonlinear second harmonic and third harmonic generations in confocal microscopy

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Science china(physics,Mechanics & Astronomy) 2004年第1期47卷 8-16页

作者： TANG Zhilie1, XING Da2 & LIU Songhao2 1. department of physics, South china Normal university, Guangzhou 510631, china 2. School for Information and Optoelectronic Science and Engineering, South china Normal university, Guangzhou 510631, china Correspondence should be addressed to Tang Zhilie (email: tangzhl@***) Received April 23, 2003 1. department of physics South China Normal University 510631 Guangzhou China 2. School for Information and Optoelectronic Science and Engineering South China Normal University 510631 Guangzhou China

The imaging theory of nonlinear second harmonic generation (SHG) and third harmonic generation (THG) in confocal microscopy is presented in this paper. The nonlinear effect of SHG and THG on the imaging properties of confocal microscopy has been analyzed in detail by the imaging theory. It is proved that the imaging process of SHG and THG in confocal microscopy, which is different from conventional coherent imaging or incoherent imaging, can be divided into two different processes of coherent imaging. The three-dimensional point spread functions (3D-PSF) of SHG and THG confocal microscopy are derived based on the nonlinear principles of SHG and THG. The imaging properties of SHG and THG confocal microscopy are discussed in detail according to its 3D-PSF. It is shown that the resolution of SHG and THG confocal microscopy is higher than that of single- and two-photon confocal microscopy.

关键词： second harmonic generation, third harmonic generation, confocal microscopy, three-dimensional point spread function.