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X-ray spectra induced by ^(129)Xe^(q+) impacting the metal surface

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Science china(physics,Mechanics & Astronomy) 2008年第1期51卷 82-89页

作者： ZHANG XiaoAn 1,2 ,XIAO GuoQing 1 ,YANG ZhiHu 1 ,CHEN XiMeng 3 ,ZHAO YongTao 1 , LI FuLi 4 ,WANG Li 1,2 ,CUI Ying 3 ,ZHANG HongQiang 3 &ZHAN WenLong 1 1Institute of modern physics,Chinese Academy of Sciences,lanzhou 730000,china 2department of physics,Xianyang Normal university,Xianyang 712000,china 3department of modern physics,lanzhou university,lanzhou 730000,china 4department of Applied physics,Xi’an Jiaotong university,Xi’an 710049,china Institute of modern physics Chinese Academy of Sciences department of physics Xianyang Normal University

Using the slow highly charged ions 129 Xe q+ (q=25,26,27;initial kinetic T0≤4.65 keV/a.u.)to impact Au surface,the Au atomic Mαcharacteristic X-ray spectrum is *** result shows that as long as the charge state of projectile is high enough,the heavy atomic characteristic X-ray can be effectively excited even though the incident beam is very weak(nA magnitude),and the X-ray yield per ion is in the order of 10-8and increases with the kinetic energy and potential energy of *** measuring the Au Mα-X-ray spectra,Au atomic N-level lifetime is estimated at about 1.33×10-18s based on Heisenberg uncertainty relation.

关键词： slow highly charged ions characteristic X-ray level lifetime

Anomalous Phenomena in E<18 keV Hydrogen Ion Beam Implantation Experiments on Pd and Ti

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Chinese journal of nuclear physics 1997年第4期19卷 244-249页

作者： Wang Tieshan~(1) Piao Yubo~(2) Hao Jifang~(1) Wang Xuezhi~(2) Jin Genming~(1) Niu Zhanqi~(2) (1)Institute of modern physics,the Chinese Academy of Sciences,lanzhou 730000 (2)department of modern physics of lanzhou university,lanzhou 730000 中科院近代物理所甘肃兰州兰州大学现代物理系甘肃兰州

Implantation experiments of low energy（1 keVmax1.2 mA/cm2)and lowbeam density(Jmin0.02 mA/cm2).Palladium and titanium foils（plates）are bombarded withproton and deuteron beams in order to compare the atomic and nuclear interactions between dif-ferent ion beams.X-ray and charged particles are measured,and neutron and gamma doses arealso monitored during the implantation *** anomalous peak in X-spectra,whoseenergy is about four times the beam energy,is observed during the high beam density *** peak moves from about 40 keV to 62 keV and FWHM reduces rapidly,while thebeam energy and intensity *** wide peak with over twice the beam energy is mea-sured in experiment with low beam *** is located between 16 keV and 30 keV,and itspeak energy increases with the increase of implantation dose（implantation time）.Some anoma-lous intensities of neutrons correlated with a charged particle peak（2.93,3.85 MeV）are alsoobserved in the deuteron-palladium *** highest neutron intensity reaches about8×104 n/s,while the beam energy and intensity are about 15 keV and 1.0 mA,respectively.

关键词： Hydrogen ion beam Low energy Implantation Palladium and titanium foils

Topological chirality and achirality of the closed circular DNAs

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Chinese Science Bulletin 1997年第20期42卷 1705-1708页

作者： QIU Wenyuan and XIN Houwen1. department of Chemical physics, university of Science and Technology of china, Hefei 230026, china 2. department of Chemistry, lanzhou university, lanzhou 730000, china Depaitment of Chemical physics University of Science and Technology of China Hefei 230026 China

THE study of the relations between the topological structure and its function is one of the focus-es in modern chemistry and life science. In this note we set up a topological model to de-scribe the ccDNAs on the basis of Seifert construction in knot theory. Our model for theccDNAs helps to determine whether a structure is topologically chiral or achiral. This is one ofthe fundamental biological problems.

关键词： DNA topology knot theory topologiesl chirality topological achirality.

Profile of the composition fractions in neutron stars

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Chinese Science Bulletin 2002年第8期47卷 632-634页

作者： LI Wenfei, ZHANG Fengshou & CHEN LiewenCenter of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, lanzhou 730000, china Institute of modern physics, Chinese Academy of Sciences, lanzhou 730000, china department of physics, Shangh Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou China Institute of modern physics Chinese Academy of Sciences Lanzhou China department of physics Shanghai Jiao Tong University Shanghai China

The composition fractions of β-stable neutron stars and their radial distributions are investigated based on Skyrme-Hartree-Fock theory and Tolman-Oppenheimer-Volkoff (TOV) equation. It is found that a pure neutron interior with a radius of 3.5 km can exist in the neutron stars. When the radius is greater than 3.5 km, the fractions of the proton, electron and μ- appear and increase with the increment of the radius, then decrease after reaching their maximum at the radius of 8 km. These results make it possible to further study the thermal evolution and magnetic properties of the neutron stars.

关键词： neutron stars compositon fractions asymmetric nuclear matter equation of state Tolman-Oppenheimer-Volkoff equation.

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 Institute of modern physics Chinese Academy of Sciences Lanzhou 730000 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.

The characteristic spectral lines of target atoms in the impact of^(40)Ar^(q+)ions on metal surfaces

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Science china(physics,Mechanics & Astronomy) 2004年第6期47卷 729-736页

作者： ZHANG Xiao’an1,2,ZHAO Yongtao1,2,LI Fuli1,YANG Zhihu2,XIAO Guoqing2 & ZHAN Wenlong2 1.department of Applied physics,Xi’an Jiaotong university,Xi’an 710049,china 2.Institute of modern physics,Chinese Academy of Sciences,lanzhou 730000,china department of Applied physics Xi'an Jiaotong University Xi'an 710049 China Institute of modern physics Chinese Academy of Sciences Lanzhou 730000 China

We report the measured results of the 200 nm—1000 nm characteristic spectral lines of target atoms when highly charged ions40Ar q+(6≤q≤14) with the same kinetic energy and40Ar6+ with different kinetic energies are incident upon Al, Ti, Ni, Ta and Au surfaces, respectively. The results for129Xe6+,129Xe10+ and129Xe15+ with the same kinetic energy (150 keV) incident upon a Ta surface are also reported. These results show that when the projectile and target are properly selected (40Ar12+ impinges on Al,129Xe6+ impinges on Ta), the spectral intensity of characteristic spectral lines of the target atom is effectively enhanced, and is not strongly dependent on the kinetic energy of the incident ions.

关键词： highly charged ion, hollow atom, characteristic spectrum, spectral intensity.

Kinetic energy and charge state effects in the X-ray emission of Mo surface induced by Xe^(q+)(q=25,29) ions

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Science china(physics,Mechanics & Astronomy) 2008年第9期51卷 1240-1244页

作者： CUI Ying1,YANG ShengSheng2,YANG ZhiHu3,XU JinZhang1,ZHANG HongQiang1,XU Xu1,SHAO JianXiong1,LIU ZhaoYuan1,XIAO GuoQing3,ZHANG XiaoAn4,ZHAO YongTao3,ZHANG YanPing3 & CHEN XiMeng1 1 department of modern physics,lanzhou university,lanzhou 730000,china 2 National Key Laboratory of Vacuum & Cryogenics Technology and physics,lanzhou 730000,china 3 Institute of modern physics,Chinese Academy of Sciences,lanzhou 730000,china 4 Normal College of Xianyang,Xianyang 713000,china department of modern physics Lanzhou University Lanzhou China National Key Laboratory of Vacuum & Cryogenics Technology and physics Lanzhou China Institute of modern physics Chinese Academy of Sciences Lanzhou China Normal College of Xianyang Xianyang China

L-shell X-ray spectra of Mo surface induced by Xe25+ and Xe29+ were measured. The X-ray intensity was obtained in the kinetic energy range of the incident ions from 350 to 600 keV. The relationship of X-ray intensity ... 详细信息

关键词： X-ray surface kinetic energy and charge state effect Xeq+

Oxyfunctionalization of ketones bearing α-methylene group with piperidine oxoammonium *** of α-diketones from monoketones

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Chinese Journal of Chemistry 1996年第3期14卷 252-258页

作者： LIU, You-Cheng REN, Tan GUO, Qing-Xiang National Laboratory of Applied Organic Chemistry, lanzhou university,lanzhou, Gansu 730000, china department of modern Chemistry, university of Science and Technology of china,Hefei, Anhui 230026, china National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China department of modern Chemistry University of Science and Technology of China Hefei Anhui 230026 China

A facile method for the title transformation is described. The reaction of 2,2,6,6-tetramethyl-4-methoxypiperidine oxoammonium chloride (1b) and ketones bearing a-methylene group in acetonitrile proceeded smoothly to give the a-oxyfunctionalized coupling products (6a-h). These coupling products decomposed upon heating in acidic medium to produce a-diketones (7a-h) in good to excellent yields.

关键词： Piperidine oxoammonium salt monoketones,α-diketones synthesis

Analysis of the negative-parity yrast band in ^(155)Tb

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Nuclear Science and Techniques 2000年第1期11卷 55-59页

作者： WU Xing-Ju XU Jin-Zhang CHEN Xing-Qu (Center of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, lanzhou 730000 physics department,Lu-an Teacher’s College,Lu-an, Anhui 237012 department of modern physics, lanzhou university, 六安师范专科学校重离子加速器国家实验室安徽六安 237012 兰州大学现代物理系重离子加速器国家实验室甘肃兰州 730000

Using the particle-rotor model, the energy spectrum and the B（MI）/B（E2） ratio of the negative-parity yrast band in 155Tb are investigated and compared with the experimental data before and after the band-crossing. It is noted that before and after the band-crossing the moment of inertia of the core is a smooth function of the total angular momentum I and can be described by the ah formula. The yrast band of 155Tb with negative parity may be triaxially deformed （γ=-13°） before and an axially symmetric shape （γ=0°） after the band-crossing.

关键词：铽155 原子核高自旋态结构性质负跃迁晕转态核子