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

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Science china(physics,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 73.000, china 2.department of modern physics, lanzhou university, lanzhou 73.000, 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 physics Lanzhou University Lanzhou 730000 China 3. department of physics Xianyang Normal College Xianyang 712000 China

The X-ray spectra of Nb surface induced by Arq+ (q =16,17) ions with the energy range from 10 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 Ar16+ ion was neutralized below the metal surface. The K shell electron of Ar16+ 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 Ar17+ is three magnitude orders larger than that of Ar16+.

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

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 73.000 (2.department of modern physics of lanzhou university,lanzhou 73.000 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

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 73.000, china 2. department of physics, Xianyang Normal university, Xianyang 712000, china 3. department of modern physics, lanzhou university, lanzhou 73.000, 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.

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 73.000, 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.

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 73.000,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.

Cross Section Measurement for ^(108)Cd(n,p)^(108)Ag^m Reaction

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Chinese journal of nuclear physics 1994年第1期16卷 59-60页

作者： Yuan Junqian Kong Xiangzhong Yang Jingkang Wang Yongchang (department of modern physics.lanzhou university.lanzhou 730001) 兰州大学近代物理系甘肃兰州 730001 兰州大学近代物理系甘肃兰州

The cross section for 108Cd（n,p）108Agm reaction is measured by the activationmethod at an incident neutron energy of 14.6±*** result is 18.1±3.3mb.

关键词： Activation cross section Long-lived radionuclides

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 73.000, 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

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 73.000, china Institute of modern physics, Chinese Academy of Sciences, lanzhou 73.000, 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.

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 73.000, 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 National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 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 [*]Address correspondence to this author at university of Science and Technology of 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