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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.Chinese academy of Meteorological sciences,{2. 100081,china 2.Nanjing institute of Meteorology,Nanjing 2.0044,china 3.institute of Atmospheric physics,Chinese academy of sciences,{2. 10002.,china Chinese academy of Meteorological sciences Beijing China Nanjing institute of Meteorology Nanjing China Chinese academy of sciences 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.

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 physics, institute of physics, Chinese academy of sciences, beijing 100080, china 2. Laboratory of Electron Microscopy, institute of physics, Chinese academy of sciences, beijing 100080, china 3. College of physics and Engineering, Qufu Normal University, Qufu 2.3165, 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 30 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 complexes of Rubisco-Rubisco activase from La^3+, Ce^3+ treatment spinach

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Science china Chemistry 2005年第1期48卷 67-74页

作者： HONG Fashui1, LIU Chao1, ZHENG Lei1, WANG Xuefeng1, WU Kang1, SONG Weiping1, Lü Shipeng1, TAO Ye2.& ZHAO Guiwen3 1. College of Life sciences, Suzhou Universty, Suzhou 2.5006, china 2. Synchrotron Radiation Laboratory, {2. of high energy physics, The Chinese academy of Science, beijing 100039, china 3. Chemical Department, University of Science and Technology of china, Hefei 2.002., china College of Life sciences Suzhou Universty Suzhou China Synchrotron Radiation Laboratory Institute of High Energy Physics The Chinese Academy of Science Beijing China Chemical Department University of Science and Technology of China Hefei China

The complex of Rubisco and Rubisco activase from LaCl3-, CeCl3- treated spinach in vivo is induced. SDS-PAGE result shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only large and small subunits (55 kD, 14.4 kD) of Rubisco, but also two large subunits of 45 kD and 41 kD near the large subunits of Rubisco. Native-PAGE shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only a band of Rubisco (560 kD), but also a band of about 1100 kD, about twice distant from Rubisco, which might be a complex of Rubisco and Rubisco activase. The purified enzyme activities from LaCl3-, CeCl3-treated spinach are 1.8 and 2.8 times that of the control,the intensities of absorption and fluorescence are sig- nificantly higher than that of the purified Rubisco from the control, and the total sulfhydryl groups and available sulfhydryl groups are 36—39 –SH per mol enzyme, 14—2. –SH per mol enzyme more than those of the purified Rubisco from the control, respectively. The CD spectra show that the secondary structure of the purified enzyme from LaCl3-, CeCl3 -treated spinach is very dif- ferent from the control. The enzyme activities from LaCl3-, CeCl3- treated spinach in vivo are 1.5 and 1.9 times those of the control.

关键词： La3+, Ce3+, spinach, Rubisco, complex of Rubisco and Rubisco acitivase, spectral characteristics.

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 {2. energy physics,Chinese academy of sciences,beijing 100049,china 2.Graduate University of Chinese academy of sciences,beijing 100049,china 3 Urumqi Observatory,NAOC Urumqi 830011,china Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate University of Chinese academy of sciences Beijing China Urumqi Observatory NAOC Urumqi 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

X（3872. and Bound State Problem of D0*0（0 D*0）

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原子核物理评论 2009年第S1期 16-21页

作者： LIU Yan-rui1,LIU Xiang2.3,DENG Wei-zhen2.(1 institute of {2. energy physics,Chinese academy of sciences,beijing 100049,china 2.Department of physics,Peking University,beijing 100871,china 3 Centro de Física Terica,Departamento de Física,Universidade de Coimbra,P-3004-516,Coimbra,Portugal)

We have performed a dynamical calculation of the bound state problem of D0D*0 by considering the pion and sigma meson exchange potential. Our preliminary analysis disfavors the molecular interpretation of X(3872. if we use the experimental D*Dπ coupling constant g=0.59 and a reasonable cutoff around 1 GeV,which is the typical hadronic scale. In contrast,there probably exists a loosely bound S-wave BB* molecular state. Such a molecular state would be rather stable since its dominant decay mode is the radiative decay through B*→Bγ.

关键词： X(3872. bound state molecule

In situ study on dendrite growth of metallic alloy by a synchrotron radiation imaging technology

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Science china(Technological sciences) 2010年第5期53卷 1278-1284页

作者： WANG TongMin1,XU JingJing1,LI Jun1,HUANG WanXia2.LIU ShengChu1 & LI TingJu1 1 School of Materials Science and Engineering,Dalian University of Technology,Dalian 11602.,china 2.institute of {2. energy physics,Chinese academy of sciences,beijing 100039,china School of Materials Science and Engineering Dalian University of Technology Dalian China institute of high {2. physics Chinese Academy of Sciences Beijing China

This study was trying to observe the real-time dendrite growth of Sn-Bi and Sn-Pb binary alloys by a synchrotron radiation imaging *** imaging system includes an intense and high brightness synchrotron radiation source,a high-resolution and fast-readout charge coupled device camera,an alloy sample and a Bridgman solidification *** imaging experiments were done at {2. Synchrotron Radiation Facility with an updated synchrotron radiation imaging technique,diffraction-enhanced imaging,which was firstly used to study the dendrite growth of metallic alloy.A series of growth behavior and morphology evolution of dendrite have been in situ observed,such as columnar-to-equiaxed transition,dendrite competition,dendrite fragmentation and floating,etc.,which can offer the direct proofs to verify or improve the solidification theories of metallic *** research opens a novel window for the study of alloy solidification and enables the unambiguous understanding of solidification processes in optically opaque,metallic alloys.

关键词： dendritic growth synchrotron radiation solidification diffraction-enhanced imaging metal and alloys

Status of study on biological and toxicological effects of nanoscale materials

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Science china Chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2.& JIA Guang3 1. Laboratory for Bio-Environmental Health sciences of Nanoscale Materials (Nanosafety Lab), institute of {2. energy physics, Chi-nese academy of sciences, beijing 100049, china 2. College of Chemistry and Molecular Engineering, Peking University, beijing 100871, china 3. Department of Occupational and Environmental Health sciences, School of Public Health, Peking University, beijing 100083, china Laboratory for Bio-Environmental Health sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences Beijing China College of Chemistry and Molecular Engineering Peking University Beijing China Department of Occupational and Environmental Health sciences School of Public Health Peking University Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

Direct numerical simulation of shock/turbulent boundary layer interaction in a supersonic compression ramp

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 1651-1658页

作者： LI XinLiang1,FU DeXun2.MA YanWen2.& LIANG Xian1 1 Key Laboratory of high Temperature Gas Dynamics,institute of Mechanics,Chinese {2. of sciences,beijing 100190,china 2.The State Key Laboratory of Nonlinear Mechanics,institute of Mechanics,Chinese {2. of sciences,beijing 100190,china Key Laboratory of high Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences Beijing China The State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing China

A direct numerical simulation of the shock/turbulent boundary layer interaction flow in a supersonic 2.-degree compression ramp is conducted with the free stream Mach number *** blow-and-suction disturbance in the upstream wall boundary is used to trigger the *** the mean wall pressure and the velocity profiles agree with those of the experimental data,which validates the *** turbulent kinetic energy budget in the separation region is *** show that the turbulent production term increases fast in the separation region,while the turbulent dissipation term reaches its peak in the near-wall *** turbulent transport term contributes to the balance of the turbulent conduction and turbulent *** on the analysis of instantaneous pressure in the downstream region of the mean shock and that in the separation bubble,the authors suggest that the low frequency oscillation of the shock is not caused by the upstream turbulent disturbance,but rather the instability of separation bubble.

关键词： compression ramp shock/turbulent boundary layer interaction direct numerical simulation shock oscillation

Isospin-dependent relativistic microscopic optical potential in the Dirac Brueckner-Hartree-Fock method

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Science china(physics,Mechanics & Astronomy) 2004年第2期47卷 189-198页

作者： RONG Jian1 & MA Zhongyu1,2.3 1. china {2. of Atomic energy, beijing 102.13, china 2. Center of Nuclear Theoretical physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lan-zhou 730000, china 3. {2. of Theoretical physics, Chinese academy of sciences, beijing 100080, china Correspondence should be addressed to Rong Jian (email: jrong@***) china institute of Atomic {2. Beijing China Center of Nuclear Theoretical physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China institute of Theoretical physics Chinese Academy of Sciences Beijing China

The relativistic microscopic optical potential in the asymmetric nuclear matter is studied in the framework of the Dirac Brueckner-Hartree-Fock method. A new decomposition of the Dirac structure of the nuclear self-energy in nuclear matter is adopted. The self-energy of a nucleon with E > 0 in nuclear matter is calculated with the G matrix in the Hartree-Fock approach. The optical potential of a nucleon in the nuclear medium is identified with the nucleon self-energy. The energy and asymmetric parameter dependence of the relativistic optical potentials for proton and neutron are discussed. The resulting Schroedinger equivalent potentials have reasonable behaviors of the energy dependence. The asymmetric parameter dependence of relativistic optical potentials and Schroedinger potentials are emphasized.

关键词： Dirac Brueckner Hartree-Fock, relativistic microscopic optical potential, asymmetric nuclear matter, isospin-dependence.

Simulation of the in-flight calibration of the collimator alignment and PSF for HXMT

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 47-50页

作者： XIONG ShaoLin,LI XinQiao,QU JinLu & LU FangJun Key Laboratory for Particle Astrophysics,institute of {2. energy physics,Chinese academy of sciences(CAS),beijing 100049,china Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences (CAS) Beijing China

The Hard X-ray Modulation Telescope(HXMT) is an X-ray astronomical satellite in 1-2.0 keV,consisting of three collimated *** present the in-flight calibration approach of the collimator alignment and Point Spread Function(PSF) for HXMT,using both the direct fitting method and the imaging *** to observational simulations of the Crab Nebula,we find that these two methods produce almost the same calibration accuracy of the alignment,and with a one-day scanning observation,the alignment can be calibrated to better than 0.45' and 0.1' along the wide and narrow directions of the Field of View(FOV) for a detector module,which corresponds to a localization accuracy of better than 0.1' and meets the scientific requirement.

关键词： HXMT alignment PSF calibration