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B_c Meson Studies

高能物理与核物理 2002年第Z1期26卷 1-10页

作者： CHANG Chao-Hsi (institute of Theoretical physics,{2., {3. 100080, China) Inst. of Theor. Phys. Chinese Acad. of Sci. Beijing 100080 China

Our studies on the meson Bc arc briefly *** decays of the meson Bc to a P-wave charmonium Xc or hc are reported comparatively precisely because they are fresh

关键词：高能物理核物理增刊张肇西 B_c Meson Studies Rev

Heavy ion reactions around the Coulomb barrier

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中国科学：物理学、力学、天文学英文版 2011年第S1期54卷 6-13页

作者： ZHANG HuanQiao1, LIN ChengJian1, JIA HuiMing1, ZHANG ChunLei1,2. ZHANG GaoLong1,3. YANG Feng1, LIU ZuHua1, AN GuangPeng1, WU ZhenDong1, XU XinXing1 & JIA Fei1 1 China institute of Atomic {2., P. O. Box 2.5(10), {2. 102.13. China 2.Particle Astro{3. Center, institute of high energy physics, chinese academy of sciences, beijing 100039, China 3.School of {3. and Nuclear {2. Engineering, Beihang University, {2. 100191, China China institute of Atomic energy Beijing China Particle Astrophysics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing China School of physics and Nuclear energy Engineering Beihang University Beijing China

The angular distributions of fission fragments for the 3.S+184W reaction near Coulomb barrier energies are measured. The ex perimental fission excitation function is obtained. The measured fission cross sections are decomposed into fusion-fission, quasi-fission and fast fission contributions by the dinuclear system (DNS) model. The hindrance to completing fusion both at small and large collision energies is explained. The fusion excitation functions of 3.S+90,96Zr in an {2. range from above to below the Coulomb barrier are measured and analyzed within a semi-classical model. The obvious effect of positive Q-value multi-neutron transfers on the sub-barrier fusion enhancement is observed in the 3.S+96Zr system. In addition, the excitation functions of quasi-elastic scattering at a backward angle have been measured with high precision for the systems of 16O+2.8Pb, 196Pt, 184W, and 154,152.m at energies well below the Coulomb barrier. Considering the deformed coupling effects, the extracted diffuseness parameters are close to the values extracted from the systematic analysis of elastic and inelastic scattering data. The elastic scattering angular distribution of 17F+12. at 60 MeV is measured and calculated by using the continuum-discretized coupled-channels (CDCC) approach. It is found that the diffuseness parameter of the real part of core-target potential has to be increased by 2.% to reproduce the experimental result, which corresponds to an increment of potential depth at the surface re gion. The breakup cross section and the coupling between breakup and elastic scattering are small.

关键词： fusion-fission quasi-fission fusion hindrance fusion enhancement surface diffuseness parameter exotic nuclei

Transport　of　atmospheric　trace　elements　and　dust－soil　to　the　Western　Pacific　Ocean

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Journal of Environmental sciences 1996年第4期8卷 460-465页

作者： Yang Shaojin Chen Bingru Yang Yinan(institute of high {2. {3.,chinese academy of sciences,beijing 100080,China) institute of high {2. {3. Chinese Academy of Sciences Beijing 100080 China

Atmospheric aerosol and rainwater samples collected in the different Western Pacific area were analyzed by instrumental neutron activation and proton induced X-ray emission to (1) determine the atmospheric concentrations of trace elements over the Western Pacific and (2. to esti mate the atmospheric deposition of trace elements and dust-soil material to this region. high abundance of pollutant and crustal elements relative to oceanic sources was observed. Some characteristics of marine atmosphere relating to long-range transport of crustal and anthropogenic elements from continent to the remote ocean are discussed. The total dust-soil particle mass is estimated to be 0. 066-1.2.μg/m￣3.over the Western Pacific Ocean areas. Atmospheric inputs of dust-soil particles control the marine particle concentrations of crustal elements. In addition, the characteristics of marine rain water are discussed.

关键词： dust-soil marine rain-water atmospheric trace elements.

A Study of Electromagnetic Transition of Δ(12.0})Resonance

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Communications in Theoretical physics 2004年第7期 87-89页

作者： DONG Yu-Bing LIU Jian institute of high energy physics, the chinese academy of sciences,{2., China

Point form relativistic dynamics of relativistic quantum mechanics is employed to estimate the photonand electroproduction amplitudes of Δ(12.0}) *** are compared with the non-relativistic work,and thedifferences betw... 详细信息

关键词： relativistic quantum mechanism point form dynamics

Dynamical Evolution of Gamma-Ray Burst Remnants with Evolving Radiative Efficiency

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chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 525-532页

作者： Jin-Bo Feng, Yong-Feng Huang, Zi-Gao Dai and Tan Lu1 Department of Astronomy, Nanjing University, Nanjing 2.0093. LCRHEA, institute for {2.-{2. {3., chinese academy of sciences, beijing 100039 Department of Astronomy Nanjing University Nanjing 210093 LCRHEA Institute for High-Energy Physics Chinese Academy of Sciences Beijing 100039

In previous works, a generic dynamical model has been suggested by Huang. et al., which is shown to be correct for both adiabatic and radiative blast-waves, in both ultra-relativistic and non-relativistic phases. In deriving their equations, Huang et al. have assumed that the radiative efficiency of the fireball is constant. They then applied their model directly to realistic cases where the radiative efficiency evolves with time. In this paper, we abandon the above assumption and re-derive a more accurate dynamical equation for gamma-ray burst remnants. Numerical results show that the model presented by Huang et al. is accurate enough in general cases.

关键词： gamma rays : bursts hydrodynamics radiation mechanisms : nonthermal

Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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Science China(physics,Mechanics & Astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3. WANG Yong2. DU Xiaolong1, MEI Zengxia1, KONG Xianghe3. JIA Jinfeng1, XUE Qikun1 & ZHANG Ze2. 4 1. State Key Laboratory for Surface {2., institute of {2.,{3., beijing 100080, China 2. Laboratory of Electron Microscopy, institute of {2.,{3., beijing 100080, China 3. College of {2. and Engineering, Qufu Normal University, Qufu 2.3.65, China 4. beijing University of Technology, beijing 10002., China State Key Laboratory for Surface physics Institute of Physics Chinese Academy of Sciences Beijing China College of physics and Engineering Qufu Normal University Qufu China Laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences Beijing China beijing University of Technology Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 3. rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high {2. electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, TEM, CBED.

Formation of super-concentrated hydrochloric acid in the third phase in tertiary amine N2.0}-PtCl_6^(2.)-HCl system and its influences on the Pt microemulsion extraction

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Science China Chemistry 2009年第11期52卷 1825-1834页

作者： HUANG Kun1,CHEN Jing1,ZHANG ChengFeng1,2.LI ZhiHong3.PAN QingHua1,SUN Yan1,LIU ShaoXuan1,LIU XueXin2.LI WeiHong1,YANG ZhanLan1,WENG ShiFu1,HU TianDou3.XU YiZhuang1 & WU JinGuang1 1 College of Chemistry and Molecular Engineering,Peking University,{2. 100871,China 2.institute of Chemistry,{2. {3. of sciences,{2. 100190,China 3.6},{2. {3. of sciences,{2. 100049,China College of Chemistry and Molecular Engineering Peking University Beijing China institute of Chemistry Chinese Academy of Sciences Beijing China institute of high {2. {3. Chinese Academy of Sciences Beijing China

In this paper,we have investigated the formation of the third-phase in tertiary amine(N2.0})-PtCl62.-HCl system and the microscopic phase structural evolution of platinum-loaded organic phases before and after the occurrence of the *** third-phase is characterized by various spectroscopic techniques,and the small angle X-ray scattering(SAXS) experiments demonstrate the appearance of nano-aggregates,i.e.,water-in-oil reversed micelles,in the third *** experimental results indicate that(1) formation of the third phase is related to the aggregation behaviors of nano-reversed micelles in which a super-concentrated hydrochloric acid formed with the H+ to H2. molar ratio being much higher than that of the conventional 3. wt% saturated hydrochloric acid.(2. The occurrence of the super-concentrated HCl results in a great amount of H+ and Cl-ions enriched and confined within the nano-water pools of W/O reversed micelles in third ***,the coordination behaviors of platinum complex ions in that super-concentrated hydrochloric acid are very different from their corresponding behaviors in bulk aqueous *** is possible that H+ ions participate in the formation of such complexes as HmPtCl6z+ in the super-concentrated hydrochloric acid.(3. The relative contents of various HmPtCl6z+ complexes are different corresponding to the H+ ion concentrations in confined nanowater *** association ability of the acidified tertiary amine N2.0} molecules(R3.H+) with various HmPtCl6z+ complexes plays an important role in affecting the platinum extraction behaviors.

关键词： solvent extraction third phase super-concentrated hydrochloric acid tertiary amine platinum

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 {2. {3., chinese academy of sciences, beijing 100080, China) institute of high {2. {3. 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 {2.er than rural and winter heating period are {2.er 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

Zonal propagation of kinetic energy and convection in the South China Sea and Indian monsoon regions in boreal summer

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Science China Earth sciences 2004年第12期47卷 1076-1084页

作者： CHEN Longxun 1 ,GAO Hui 2.,HE Jinhai 2.,TAO Shiyan 3.& JIN Zuhui 3.1.{2. academy of Meteorological {2.,{3. 100081,China 2.Nanjing institute of Meteorology,Nanjing 2.0044,China 3.institute of Atmospheric physics,{2. academy of {2.,{3. 10002.,China chinese academy of Meteorological {2. Beijing China Nanjing institute of Meteorology Nanjing China chinese academy of {2. Institute of Atmospheric Physics Beijing China

Zonal propagation of kinetic energy (KE) and convection in the South China Sea (SCS) and Indian summer monsoon areas are examined in present study. Results suggest that the SCS and Indian summer monsoon prevailed regions (5 —15°N) are dominated by the southwesterly wind, however, the disturbances of KE at 850 hPa and convection are observed mainly coming from the western Pacific Ocean (140—150°E), after passing through the SCS, and westward propagated into the Bay of Bengal (90—100°E). In the Indian summer monsoon domain, where the disturbances of KE are found mainly coming from the Arabian Sea (AS) and eastward propagated into the Bay of Bengal. Therefore, the SCS and the Indian summer mon- soon are quite different in zonal propagation of KE and convection. The SCS summer monsoon is mainly affected by the KE and convection coming from the tropical western Pacific. The Indian summer monsoon, however, can be partly influenced by the AS and the SCS summer monsoon. The analysis also suggests that the interaction region between the SCS and the Indian summer monsoon is around 90—95°E, rather than 105°E as proposed by earlier studies.

关键词： zonal propagation of KE and convection, East Asian monsoon, Indian monsoon.