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The rms-flux relation of Cyg X-2.in the horizontal branch

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中国科学：物理学、力学、天文学英文版 2010年第S1期53卷 86-90页

作者： LI ZhiBing,LEI YaJuan,QU JinLu,ZHANG Shu & SONG LiMing Key Laboratory for Particle Astrophysics,institute of {2. {3. 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

We have investigated the relation between the root mean square(rms) variability and the X-ray flux(rms-flux relation) of the Z source Cyg X-2.and as well the energy dependence based on the Rossi X-ray Timing Explorer(RXTE) *** currently focus on the horizontal branch(HB),due to the negative correlation in flux of the soft and the hard *** rms-flux correlation has energy dependence as follows:positive at hard X-rays(above 10 keV) but negative at soft X-rays(below 10 keV).This provides a feature different from the previous one,and may be suggestive of different origins of X-rays below and above 10 ***,the overall spectrum can be well fitted with a model consisting of a blackbody and Comptonization components,but the fitting results do not reveal any features around 10 keV that could account for such a change in the rms-flux relation.

关键词： accretion accretion disk—binaries:close-stars:individual(Cygnus X-2.-X-rays:binaries

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, {2. of Armored Forces Engineering of PLA, {2. 100072. China2.{3. of high energy physics, chinese {2. of Sciences, beijing 100049, China3.{3. 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

A study on the sharp knee and fine structures of cosmic ray spectra

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Science China(physics,Mechanics & Astronomy) 2010年第5期53卷 842-847页

作者： WANG Bo1,YUAN Qiang1,FAN Chao1,2.ZHANG JianLi1,HU HongBo1 & BI XiaoJun1 1 Key Laboratory of Particle Astrophysics,institute of {2. {3. physics,chinese academy of Sciences,beijing 100049,China 2.Department of physics,Shandong University,Jinan 2.0100,China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Department of physics Shandong University Jinan China

The paper investigates the overall and detailed features of cosmic ray(CR) spectra in the knee region using the scenario of nuclei-photon interactions around the acceleration *** supernova remnants can be the physical realities of such kind of CR acceleration *** results show that the model can well explain the following problems simultaneously with one set of source parameters:the knee of CR spectra and the sharpness of the knee,the detailed irregular structures of CR spectra,the so-called"component B"of Galactic CRs,and the electron/positron excesses reported by recent *** coherent explanation serves as evidence that at least a portion of CRs might be accelerated at the sources similar to young supernova remnants,and one set of source parameters indicates that this portion mainly comes from standard sources or from a single source.

关键词： cosmic ray knee fine structures e+e-excesses "component B" single source

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. {2. {3., 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.

Threading dislocation density comparison between GaN grown on the patterned and conventional sapphire substrate by high resolution X-ray diffraction

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Science China(physics,Mechanics & Astronomy) 2010年第3期53卷 465-468页

作者： ZHANG YuChao1, XING ZhiGang2. MA ZiGuang2. CHEN Yao2. DING GuoJian2. XU PeiQiang2. DONG ChenMing3. CHEN Hong2.& LE XiaoYun1 1 School of physics and Nuclear {2. Engineering, Beihang University, {2. 100190, China 2.Renewable {2. Laboratory, institute of physics, chinese academy of Sciences, {2. 100190, China 3.School of Information and Communication, Tianjin Polytechnic University, Tianjin 3.0160, China School of physics and Nuclear energy Engineering Beihang University Beijing China Renewable energy Laboratory Institute of Physics Chinese Academy of Sciences Beijing China School of Information and Communication Tianjin Polytechnic University Tianjin China

GaN epifilms are grown on the patterned sapphire substrates (PSS) (0001) and the conventional sapphire substrates (CSS) (0001) by metal-organic chemical vapor deposition (MOCVD) using a novel two-step growth. high resolution X-ray diffraction (HR-XRD) is used to investigate the threading dislocation (TD) density of the GaN epifilms. The TD density is calculated from the ω-scans full width at half maximum (FWHM) results of HR-XRD. The edge dislocation destiny of GaN grown on the PSS is 2.7×108 cm-2. which is less than on the CSS. This is confirmed by the results of atomic force microscopy (AFM) measurement. The lower TD destiny indicates that the crystalline quality of the GaN epifilms grown on the PSS is improved compared to GaN epifilms grown on the CSS. The residual strains of GaN grown on the PSS and CSS are compared by Raman Scattering spectra. It is clearly seen that the residual strain in the GaN grown on PSS is lower than on the CSS.

关键词： GaN patterned sapphire substrate threading dislocation XRD

Conceptual design and simulation analysis of thermal behaviors of TGR blast furnace and oxygen blast furnace

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Science China(Technological Sciences) 2010年第1期53卷 85-92页

作者： ZHANG Hui1,2.LI HuiQuan1,TANG Qing1 & BAO WeiJun1 1 National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology,institute of Process Engineering,chinese {2. of Sciences,{3. 100190,China 2.Graduate University of chinese {2. of Sciences,beijing 100049,China National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process Engineering Chinese Academy of Sciences Beijing China Graduate University of chinese academy of Sciences Beijing China

Extensive use of carbon based fuel is the main inducement for global warming and more extreme *** carbon dioxide emission and enhancing energy use is a common subject in steel *** the integrated steel plant,decreasing carbon dioxide emission must consider energy balance in the whole iron and steel works,and secondary energy must be actively *** promising blast-furnaces,top gas recovery blast furnace(TGR-BF) and oxygen blast furnace have been *** this paper,conceptual TGR blast furnace and oxygen blast furnace are *** on the idea of blast furnace gas de-CO2.circulating as reducing agent and the idea of pure oxygen blast decreasing the thermal reserve zone temperature,process modeling is conducted with ASPEN *** is shown that the developed model reasonably describes the energy balance and mass balance feature of the furnace,and provides basic thermodynamic condition for *** effects of changes in different operation conditions are studied by sensitivity analysis and reference data from simulation.

关键词： TGR blast-furnace thermal behavior simulation analysis CO2 emission decreasing

Phylogeny and species delimitation of the C-genome diploid species in Oryza

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Journal of Systematics and Evolution 2011年第5期49卷 386-395页

作者： 1,2.Li-Li ZANG 1~Xin-Hui zou 1~Fu-Min ZHANG 3.4~Ziheng YANG 1,2.Song GE 1(State Key Laboratory of Systematic and Evolutionary Botany,{2. of Botany,chinese {3. of Sciences,beijing 100093.China) 2.Graduate University of the chinese {3. of Sciences,beijing 100049,China) 3.Department of Biology,University College London,London WC1E 6BT,United Kingdom) 4(Center for Computational and Evolutionary Biology,{2. of Zoology,chinese {3. of Sciences,beijing 100101,China) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the chinese academy of Sciences Beijing 100049 China) (Department of Biology University College London London WC1E 6BT United Kingdom) (Center for Computational and Evolutionary Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China)

The diploid Oryza species with C-genome type possesses abundant genes useful for rice improvement and provides parental donors of many tetraploid species with the C-genome(BBCC,CCDD).Despite extensive studies,the phylogenetic relationship among the C-genome species and the taxonomic status of some taxa remain *** this study,we reconstructed the phylogeny of three diploid species with C-genome(Oryza officinalis,***,and ***) based on sequences of 68 nuclear single-copy *** obtained a fully resolved phylogenetic tree,clearly indicating the sister relationship of *** and ***,with *** being the more divergent *** phylogenies of the C-genome species found in previous studies might result from lineage sorting,introgression/hybridization and limited number of genetic markers *** further applied a recently developed Bayesian species delimitation method to investigate the species status of the Sri Lankan and African *** of two datasets(68 genes with a single sample,and 10 genes with multiple samples) support the distinct species status of the Sri Lankan and African *** addition,we evaluated the impact of the number of sampled individuals and loci on species *** simulation suggests that sampling multiple individuals is critically important for species delimitation,particularly for closely related species.

关键词： Bayesian species delimitation Oryza phylogeny taxonomy.

Prediction method for October 2.03.solar storm

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Science China(Technological Sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2. 3. WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2.1. State Key Laboratory of Space Weather, Center for Space Science and Applied Research, chinese {2. of Sciences, {2. 100080, China 2. Graduate School, chinese {2. of Sciences, {2. 10003., China 3. institute of Meteorology, PLA University of Science and Technology, Nanjing 2.1101, China State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China institute of Meteorology PLA University of Science and Technology Nanjing China

Aiming at two intense shock events on October 2. and 2., 2.03. this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely {2. temperature, the strong magnetic field, and the {2. speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

Cyclic Heating-Annealing and Boltzmann Distribution of Free Energies in a Spin-Glass System

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Communications in Theoretical physics 2007年第7期48卷 179-182页

作者： ZHOU Hai-Jun institute of Theoretical physics,the {2. {3. of Sciences,beijing 100080,China institute of Theoretical physics the Chinese Academy of Sciences Beijing 100080 China

Ergodicity of a spin-glass is broken at low temperatures;the system is trapped in one of many ergodicconfigurational *** between different ergodic domains are achievable through a *** this experiment is repeated infinite times,all ergodic configurational domains will be visited with frequencesthat decreasing exponentially with their free *** mean free energy density of a spin-glass system on a randomgraph is calculated based on this free energy Boltzmann distribution in the present work,by means of the cavity approach.

关键词： spin-glass ergodicity-broken cavity method