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Geometry of Broad Line Regions of Active Galactic Nuclei

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chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 50-62页

作者： Xiao-Rong Lü1 Key laboratory for Particle Astrophysics, {2. of High energy physics, chinese academy of sciences, beijing 100049 2.Graduate School of chinese academy of sciences, beijing 100049 Key laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 and Graduate School of chinese academy of sciences Beijing 100049

It has long remained an open question as to the geometry of the broad line region （BLR） in active galactic nuclei （AGNs）. The reverberation mapping technique which measures the response of the broad emission lines to the ionizing continuum, when combined with multiwavelength continuum fitted by sophisticated accretion disks, provides a way of probing the BLR geometry. We analyze a sample of 35 AGNs, which have been monitored by the reverberation mapping campaign. In view of energy budget, the reverberation-based BH masses are found to be in agreement with those obtained by accretion disk models in two thirds of the present sample while the reverberation mapping methods underestimate the BH masses in about one third of objects, as also suggested by CoUin et al. in a recent work. We point out that there are obviously two kinds of BLR geometry, which are strongly dependent on the Eddington ratio, and separated by the value LBol/LEdd - 0.1. These results prefer a scenario of the disk and wind configuration of the BLR and identify the Eddington ratio as the physical driver regulating the wind in the BLR.

关键词： accretion, accretion disks - galaxies active - galaxies Seyfert - quasars general

Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(2..5) bulk metallic glass up to 2. GPa

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Science China(physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2., ZHAN Zaiji 2., LIU Jing 3 , YUN Jinku 1 , SUN Liling 2., LIU Riping 1 , ZHANG Jun 2.& WANG Wenkui 1, 2.1. Key laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China 2. Center for Condensed Matter physics,{2., chinese academy of sciences, beijing 100080, China 3. BSRF, institute of High energy physics, chinese academy of sciences, beijing 100039, China 1. Key laboratory of Metastable Materials Science and Technology Yanshan University 066004 Qinhuangdao China 2. Center for Condensed Matter physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be2..5 bulk metallic glass (BMG) is investigated at room temperature up to 2. GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.

Exploration of combined adjustment laws about IGV,stator and rotational speed in off-design conditions in an axial compressor

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中国科学：技术科学英文版 2010年第4期53卷 969-975页

作者： HU YanMing1,2.& NIE ChaoQun1 1 Key laboratory of Advanced energy and Power Technology,{2. of Engineeting Thermophysics,chinese academy of Science,beijing 100190,China 2.Graduate School of chinese academy of sciences,beijing 100190,China 1. Key laboratory of Advanced energy and Power Technology Institute of Engineeting Thermophysics Chinese Academy of Science Beijing 100190 China2. Graduate School of Chinese Academy of Sciences Beijing 100190 China

Experimental investigations are performed in a three-stage low-speed axial compressor with variable inlet guide vanes(IGV) and adjustable *** characteristics of the compressor,especially the efficiency and stall margin,are analyzed in design and off-design operation conditions by adjusting stagger angles of IGV and stators as well as changing the rotational *** experimental results show that the off-design performance of the multistage axial compressor is improved by restaggering of IGV and stators related to rotational *** the background of engineering applications,digital signal processing(DSP) technique is used to realize online adjustment of stagger angles according to the corresponding relations between incidence angles of rotor and rotational speed.

关键词： axial compressor IGV surge DSP techniques off-design

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 energy Engineering, Beihang University,{2., China 2.renewable energy laboratory, institute of physics, chinese academy of sciences,{2., China 3 School of Information and Communication, Tianjin Polytechnic University, Tianjin 300160, China 1. School of physics and Nuclear energy Engineering Beihang University Beijing 100190 China2. Renewable Energy Laboratory Institute of Physics Chinese Academy of Sciences Beijing 100190 China3. School of Information and Communication Tianjin Polytechnic University Tianjin 300160 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

Research of the Gas-solid Flow Character Based on the DEM Method

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Journal of Thermal Science 2011年第6期20卷 521-526页

作者： Xueyao Wang and Yunhan Xiao Research Center for Clean energy and Power,chinese {2. of sciences Key laboratory of Advanced energy and Power,chinese {2. of sciences (institute of Engineering Thermophysics),beijing,{12.,China Research Center for Clean energy and Power Chinese Academy of Sciences Beijing China Key laboratory of Advanced energy and Power Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing China

Numerical simulation of gas-solid flow behaviors in a rectangular fluidized bed is carried out three dimensionally by the discrete element method (DEM).Euler method and Lagrange method are employed to deal with the gas phase and solid phase *** collided force among particles,striking force between particle and wall,drag force,gravity,Magnus lift force and Saffman lift force are considered when establishing the mathematic ***-sphere model is used to describe the collision of *** addition,the Euler method is also used for modeling the solid phase to compare with the results of *** flow patterns,particle mean velocities,particles' diffusion and pressure drop of the bed under typical operating conditions are *** results show that the DEM method can describe the detailed information among particles,while the Euler-Euler method cannot capture the micro-scale *** matter which method is used,the diffusion of particles increases with the increase of gas *** the gathering and crushing of particles cannot be simulated,so the energy loss of particles' collision cannot be calculated and the diffusion by using the Euler-Euler method is *** addition,it is shown by DEM method,with strengthening of the carrying capacity,more and more particles can be schlepped upward and the dense suspension upflow pattern can be ***,the results given by the Euler-Euler method are not consistent with the real situation.

关键词： DEM gas-solid flow numerical simulation

Strong decays of N~*(1535) in an extended chiral quark model

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Science China(physics,Mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN ChunSheng1,2.3 & ZOU BingSong1,2.3 1 institute of High energy {2.,chinese academy of sciences,beijing 100049,China 2.Theoretical {2. Center for Science Facilities,chinese academy of sciences,beijing 100049,China 3 Graduate University of{12.,beijing 100049,China institute of High energy {2. Chinese Academy of Sciences Beijing 100049 China Theoretical physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China Graduate University of chinese academy of sciences Beijing 100049 China

The strong decays of the N*(1535) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(1535) contribute significantly to the N*(1535) → Nπ and N*(1535) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(1535) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(1535) strong decays five-quark components

The establishment of crystal position look-up table for positron emission tomography with block detectors

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Science China(Technological sciences) 2009年第8期52卷 2418-2423页

作者： CHAI Pei1,2.& SHAN BaoCi1 1 Key laboratory of Nuclear Analytical Techniques, institute of High {2. physics, chinese academy of sciences, beijing 100049, China 2.Graduate University of chinese academy of sciences, beijing 100049, China Key laboratory of Nuclear Analytical Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Graduate University of chinese academy of sciences Beijing 100049 China

A method has been developed to establish the crystal position look-up table for positron emission tomography with block detectors. It is based on the principle that the counts in crystal position histogram obey the Gaussian mixture model (GMM). This method has taken full consideration of the characteristics of the GMM and the detector itself. The experimental results have proved that it is simple, reliable, and universal.

关键词： positron emission tomography position look-up table 2.D position histogram

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,{2. academy of sciences,beijing 100190,China 2.The State Key laboratory of Nonlinear Mechanics,institute of Mechanics,{2. academy of sciences,beijing 100190,China 1. Key laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China2. The State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100190 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

Studies on BEPC upgrade from pretzel to double-ring

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Science China(physics,Mechanics & Astronomy) 2010年第11期53卷 2084-2089页

作者： ZHANG Chuang institute of High energy {2.,chinese academy of sciences,beijing 100049,China 1. institute of High energy {2. Chinese Academy of Sciences Beijing 100049 China

physics opportunity in the charm and τ energy region calls for higher luminosity of the {2. Electron-Positron Collider (BEPC).The BEPC has experienced continuous improvement since its completion in ***,as a major upgrading project of the BEPC,aims at enhancing its luminosity of factor 30–100,following the principle of "one machine,two purposes" as adopted in BEPC,so that both high energy physics and synchrotron radiation experiments can be carried out with *** the BEPC to BEPCII,the double-ring scheme with multi-bunch e +-e-collision in the large crossing angle was studied in comparison with the single-ring pretzel *** the dedicated synchrotron radiation operation,artful "bridges" are designed to connect two halves of the outer ring in both the southern and the northern crossing *** paper reviews the studies on the BEPC upgrade from pretzel to double-ring structure of BEPCII.

关键词： collider storage ring high energy physics synchrotron radiation