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The time lag spectrum of Cir X-1 on its normal branch

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 60-63页

作者： QU JinLu1,LU Yu1,2.DING GuoQiang3.ZHANG Fan1,LEI YaJuan1 & LI ZhiBing1 1 Key Laboratory for Particle Astrophysics,institute of High {2. physics,Chinese academy of sciences,beijing 100049,china 2.Graduate University of Chinese academy of sciences,beijing 100049,china 3.Urumqi Observatory,NAOC Urumqi 83.011,china 1. Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Urumqi Observatory NAOC Urumqi 830011 China

In the radiation-hydrodynamics model,the time lag and fractional root-mean-squared(rms) amplitude as a function of emitted photon energy should show a minimum on the normal branch *** has been seen in the Z-sources Cyg X-2.and GX ***,using the observations from the Rossi X-ray Timing Explorer(RXTE),we study the energy dependence of normal branch QPOs in the peculiar Z-source Cir *** discuss the results in the context of radiation-hydrodynamics and the Comptonization model.

关键词： Cir X-1 temporal variability QPO time lag

Structural stability of infinite-layer CaCuO_2.under high pressure

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Chinese Science Bulletin 2003年第12期48卷 1201-1203页

作者： QIN Xiaomei1,2. HONG Ming1,2. ZHANG Gongmu1,2. MAI Wenjie1,2. LI Fengying1,2. YU Richeng1,2. LIU Jing2.3.& JIN Changqing1,2.1. institute of {2., Chinese academy of sciences, beijing 100080, {13. 2. beijing High Pressure Research Center, beijing 100080, {13. 3. institute of High energy {2., Chinese academy of sciences, beijing 10003., {13. Correspondence should be addressed to Jin Changqing (e-mail: cqjin@ ***) institute of physics Chinese Academy of Sciences Beijing 100080 China beijing High Pressure Research Center Beijing 100080 China institute of High energy {2. Chinese Academy of Sciences Beijing 100039 China

In situ high-pressure energy dispersive X-ray diffraction measurements on polycrystalline powder Ca-CuO2.with an infinite layer structure (IL CaCuO2. have been performed by using diamond anvil cell (DAC) instrument with synchrotron radiation. The results suggest that the crystal structure of IL CaCuO2.is stable under pressure up to 3. GPa at room temperature. According to Birch-Murn- aghan equation of state, assuming pressure derivative 4,=0Bthe bulk modulus B0=181 ?9 GPa is obtained.

关键词： infinite-layer CaCuO2 synchrotron radiation high pressure energy dispersive X-ray diffraction.

Current distribution and stability of LTS/HTS hybrid superconducting conductors

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Science china(Technological sciences) 2010年第7期53卷 2000-2007页

作者： GUAN XiaoJin1,2. WANG YinShun1 & ZHOU WeiWei3.1 Key Laboratory of HV and EMC beijing, North china Electric Power University, beijing 102.06, china 2.Department of physics, Baoding University, Baoding 071000, china 3.institute of Electrical Engineering, Chinese academy of sciences, beijing 100190, china 1. Key Laboratory of HV and EMC beijing North China Electric Power University Beijing 102206 China2. Department of Physics Baoding University Baoding 071000 China3. Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190 China

Current distribution and stability of a hybrid LTS/HTS superconductor, consisting of multifilamentary NbTi/Cu and Bi2.0}/Ag tapes, were numerically analyzed according to power-law models. The results showed that most of current passed through the LTS and the current increased in the HTS with temperature rise when the transport current was below the critical current of the hybrid conductor. The quench propagation velocity of the hybrid conductor was smaller but its minimum quench energy was larger than those of LTS conductors, indicating that the stability of the hybrid superconducting conductor was effectively improved and a high engineering current density was simultaneously achieved. Finally, a hybrid sample, made by soldering Bi2.0}/Ag tape onto NbTi/Cu conductor, was prepared and tested successfully at helium temperature. The experimental results qualitatively agreed with the simulated ones.

关键词： distribution hybrid conductor minimum quench energy quench propagation velocity n value stability

CHEMICAL STRUCTURE DEPENDENCE OF THE INTERNAL energy CONTRIBUTION IN RUBBER ELASTICITY

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Chinese Journal of Polymer Science 2001年第5期19卷 447-449页

作者： Juan Sun Xiao-zhen Yang Polymer physics Laboratory Center for Molecular sciences, {2. of Chemistry Chinese {3. of sciences beijing 100080 china Chinese Acad Sci Polymer Phys Lab Ctr Mol Sci Inst Chem Beijing 100080 Peoples R China

Conformational elasticity theory recently developed has been used to explore the internal energy contribution to the elastic force f(e)/f as a function of strain for poly(cis-1,4-isoprene) and poly(trans-1,4-isoprene). Calculated f(e)/f values are in good agreement with those obtained experimentally. Results show that behavior of f(e)/f is mainly contributed by chemical structure, or intramolecular interaction, supporting the experimental observations, and that the internal energy contribution is strain dependent.

关键词： conformational elasticity theory internal energy contribution poly(cis-1,4-isoprene) poly(trans-1,4-isoprene)

Characteristics of air particulate matter and their sources in urban and rural area of beijing, china

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Journal of Environmental sciences 2000年第4期12卷 402-409页

作者： YANG Shao jin, DONG Jin quan, CHENG Bing ru (institute of High energy {2., Chinese {3. of sciences, beijing 100080, china) institute of High energy {2. Chinese Academy of Sciences Beijing 100080 China

During October 1993.and March 1996, the samples of fine and coarse air particulate matter have been collected at representative urban and rural site of beijing with the Gent Stacked Filter Unit Sampler. Instrumental neutron activation analysis (INAA) and proton induced X ray emission (PIXE) method were used to determine the elemental composition of the particulate matter. Average elemental concentrations and enrichment factors were calculated for the fine and coarse size fractions. Based on the particulate matter data obtained at urban and rural site together with the chemical constituents of the aerosol from the different sources are discussed. The results show that the relative particulate mass and elemental concentrations of crustal and pollutant elements in the air particulate matter collected over the urban are higher than rural and winter heating period are higher than in ordinary season. beijing atmosphere is polluted by aerosols from regional and faraway sources. It was noticed that the toxic or harmful elements such as As, Sb, Pb, Cu, Ni, S and Zn were mainly enriched in fine particles with diameter less than 2.μm. A receptor model was used to assess the relative contribution of major air pollution sources at receptor sites in beijing. Trace elements were used as the markers for the above assessment. Factor analysis method was used to identify possible emission sources of air particles. The major sources of dust soil, coal burning, motor vehicle emission, industry emission and refuse incineration were identified.

关键词： atmospheric particulate matter urban rural source aerosol

Systematic study of survival probability of excited superheavy nuclei

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 109-113页

作者： XIA ChengJun1, SUN BaoXi1, ZHAO EnGuang2.3.& ZHOU ShanGui2.3.1College of Applied {2., {3. University of Technology, {3. 10012., china 2.6} of Theoretical physics, Chinese academy of {2., {3. 100190, china 3.enter of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 73.000, china Chinese Acad Sci Inst Theoret Phys Beijing 100190 Peoples R China beijing Univ Technol Coll Appl Sci Beijing 100124 Peoples R China Ctr Theoret Nucl Phys Natl Lab Heavy Ion Accelerator Lanzhou 730000 Peoples R China

The stability of excited superheavy nuclei (SHN) with 100 Z 13. against neutron emission and fission is investigated by using a statistical model. In particular, a systematic study of the survival probability against fission in the 1n-channel of these SHN is made. The present calculations consistently take the neutron separation energies and shell correction energies from the calculated results of the finite range droplet model which predicts an island of stability of SHN around Z = 115 and N = 179. It turns out that this island of stability persists for excited SHN in the sense that the calculated survival probabilities in the 1n-channel of excited SHN at the optimal excitation energy are maximized around Z = 115 and N = 179. This indicates that the survival probability in the 1n-channel is mainly determined by the nuclear shell effects.

关键词： survival probability superheavy elements island of stability neutron emission fission

Fabrication of atomically smooth SrRuO_3.thin films by laser molecular beam epitaxy

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Science china(physics,Mechanics & Astronomy) 2008年第7期51卷 745-749页

作者： LIU GuoZhen1, HE Meng1, JIN KuiJuan1, YANG GuoZhen1, Lü HuiBin1, ZHAO Kun2. ZHENG ShiJian3.& MA XiuLiang3.1 beijing National Laboratory for Condensed Matter physics, {2. of physics, Chinese academy of sciences, beijing 100080, china 2.Department of Mathematics and physics, china University of Petroleum, beijing 102.49, china 3.Shenyang National Laboratory for Materials Science, {2. of Metal Research, Chinese academy of sciences, Shenyang 110016, china 1. beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 2. Department of Mathematics and physics China University of Petroleum Beijing 102249 China 3. Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

High-quality SrRuO3.(SRO) thin films and SrTiO3.SRO bilayer were grown epitaxially on SrTiO3.(STO)(001) substrates by laser molecular beam epitaxy. The results of in situ observation of reflection high-energy electron diffraction and ex situ X-ray diffraction θ -2. scan indicate that the SRO thin films have good crystallinity. The measurements of atomic force microscopy and scan tunneling microscopy reveal that the surface of the SRO thin film is atomically smooth. The resistivity of the SRO thin film is 3.0 μΩ·cm at room temperature. Furthermore, the transmission electron microscopy study shows that the interfaces of STO/SRO and SRO/STO are very clear and no interfacial reaction layer was observed. The experimental results show that the SRO thin film is an excellent electrode material for devices based on perovskite oxide materials.

关键词： SrRuO3 thin film laser molecular beam epitaxy surface morphology

xF(or y)-Dependence of Nuclecir Absorption and energy Loss Effects on J/ψ Production

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Communications in Theoretical physics 2009年第12期52卷 1049-1054页

作者： WANG Hong-Min,~(1,*) SUN Xian-Jing,~2.and ZHANG Ben-Ai~3. physics Department, academy of Armored Forces Engineering of PLA, {2. 100072. china2.institute of High energy physics, Chinese academy of sciences, beijing 100049, china3.institute of Applied physics and Computation Mathematics, {2. 100088, china

By means of the nuclear parton distribution studied only with lepton deep-inelastic scattering experimentaldata,the J/φ"normal nuclear absorption"and energy loss effects are studied in a Glauber formalism at HERA andRHIC *** that the absorption cross section σincreases with the charmonium-nucleon center of massenergy,the results reveal a significant dependence of the σon rapidity y at RHIC *** initial-state energyloss effect,which is found important only at HERA energies,is also considered,and its influence should be eliminatedwhen we studied the absorption effect at low collision ***,we also present the theoretical prediction forLHC.

关键词： x_F (or y)-dependence of absorption effect Glauber formalism energy loss

Zircon and apatite fission track analyses on mineralization ages and tectonic activities of Tuwu-Yandong porphyry copper deposit in northern Xinjiang, china

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Science china Earth sciences 2007年第12期50卷 1787-1795页

作者： YUAN WanMing1,BAO ZengKuan2.DONG JinQuan2.GUO ZhaoJie3.& DENG Jun1 1 State Key Laboratory of Geological Processes and Mineral Resources,china University of Geo{3.,{2.100083.china 2.Laboratory of Nuclear Analysis Techniques,institute of High energy physics,Chinese academy of {3.,{2. 10003.,china 3.Department of Geology,Peking University,{2. 100871,china 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China 3. Department of Geology Peking University Beijing 100871 China

The mineralization ages reported in the past in the Tuwu-Yandong copper district not only are different,but also fall into the Hercynian *** study has achieved 9 zircon and 7 apatite fission track analysis *** zircon fission track ages range from 158 Ma to 2.9 Ma and the apatite ages are between 64 Ma and 140 *** mineralization accords with the regional tectonics in the copper *** consider that the zircon fission track age could reveal the mineralization age based on annealing zone temperature of 140―3.0℃ and retention temperature of ～2.0℃ for zircon fission track,and metallogenetic temperature of 12.―3.0℃ in this ore *** three mineralization epochs have been identified,i.e.,2.9―2.6 Ma,2.2.2.0 Ma and 165―158 Ma,and indicate occurrence of the min-eralization in the Indosinian and Yanshan *** to apatite fission track ages,the three tectonic-mineralizing epochs are 140―13.0}Ma,109―97 Ma and 64 Ma,which means age at about 100℃ after the *** three epochs lasted 146 Ma,108 Ma and about 100 Ma from ～2.0℃ to ～100℃ and trend decrease from early to *** is shown by the fission track modeling that this district underwent three stages of geological thermal histories,stable in Cretaceous and cooling both before Cretaceous and after 2. Ma.

关键词： mineralization age, tectonic epoch, fission track, zircon, apatite, Tuwu-Yandong, Xinjiang