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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 {3.physics, institute of high energy Physics, chinese academy of sciences, beijing 100049 2 Graduate School of chinese academy of sciences, beijing 100049 key laboratory for particle {3.physics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 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 3. 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

A 12-bit multichannel ADC for pixel detectors in particle physics and nuclear imaging

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Science china(Technological sciences) 2010年第5期53卷 1208-1214页

作者： WEI Wei1,2,3.WANG Zheng1,3.& ZHAO JingWei1,3.1 institute of high energy Physics,{3. academy of sciences,beijing 100049,china 2 Graduate University of chinese academy of sciences,beijing 100049,china 3.{13. Lab of Nuclear Detection Technology and Nuclear Electronics of chinese academy of sciences,beijing 100049,china institute of high energy Physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China key Lab of Nuclear Detection Technology and Nuclear Electronics of chinese academy of sciences Beijing China

Modern pixel detectors in nuclear and particle physics experiments and also in nuclear imaging,starve for highly integrated application specified integrated circuit(ASIC),whereas in china the study of ASIC still stays far away from practical *** lack of ASIC strictly limits the research and development of domestic high energy physics field.A 12-bit multichannel ADC designed for high density readout is introduced as a major candidate for solution.A precise model is discussed and the simulation fully agrees with the model,which indicates a key principle of *** is performed according to the given rule,and novel layout techniques are carried *** results in all aspects are also obtained,showing an excellent real performance,which satisfies the practical requirement.

关键词： application specified integrated circuit high density readout Wilkinson ADC multi-channel ADC

Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science china(Physics,Mechanics & astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2,3., HU Chen 2 , WANG JianMin 2 , BIAN WeiHao 4 , ZHANG Shu 2 & ZHAO Gang 1 1 key laboratory of Optical astronomy, National astronomical Observatories, chinese academy of sciences, beijing 100012, china 2 key laboratory for particle astrophysics, institute of high {13. Physics, chinese academy of sciences, beijing 100049, china 3.Graduate University of the chinese academy of sciences, beijing 100049, china 4 Department of Physics, Nanjing Normal University, Nanjing 210011, china key laboratory of Optical astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing China key laboratory for particle {3.physics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate University of the chinese academy of sciences Beijing China Department of Physics Nanjing Normal University Nanjing China

A sample consisting of 211 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(22.5) bulk metallic glass up to 24 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, {3. of Physics, chinese academy of sciences, beijing 100080, china 3. BSRF, {3. of high energy Physics, chinese academy of sciences, beijing 10003., china key laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao China Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China BSRF Institute of High Energy Physics Chinese Academy of Sciences Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass (BMG) is investigated at room temperature up to 24 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.

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 {3. energy 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 China Graduate University of chinese academy of sciences Beijing 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

Relative importance of water, energy, and heterogeneity in determining regional pteridophyte and seed plant richness in china

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Journal of Systematics and Evolution 2011年第2期49卷 95-107页

作者： 1,2,3.Sheng-Bin CHEN § 1 Gao-Ming JIANG 3.Zhi-Yun OUYANG 3.Wei-Hua XU 3.Yi XIAO 1 (State key laboratory of Vegetation and Environmental Change, institute of Botany,{3., beijing 100093. china) 2 (Graduate University of the{3., beijing 100049, china) 3.(State key laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental sciences,{3., beijing 100085, china) (State key laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) (State key laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China)

Environmental variables, such as ambient energy, water availability, and environmental heterogeneity have been frequently proposed to account for species diversity gradients. How taxon-specific functional traits define large-scale richness gradients is a fundamental issue in understanding spatial patterns of species diversity, but has not been well documented. Using a large dataset on the regional flora from china, we examine the contrast spatial patterns and environmental determinants between pteridophytes and seed plants which differ in dispersal capacity and environmental requirements. Pteridophyte richness shows more pronounced spatial variation and stronger environmental associations than seed plant richness. Water availability generally accounts for more spatial variance in species richness of pteridophytes and seed plants than energy and heterogeneity do, especially for pteridophytes which have {3. dependence on moist and shady environments. Thus, pteridophyte richness is disproportionally affected by water-related variables; this in turn results in a {3.er proportion of pteridophytes in regional vascular plant floras (pteridophyte proportion) in wet regions. Most of the variance in seed plant richness, pteridophyte richness, and pteridophyte proportion explained by energy is included in variation that water and heterogeneity account for, indicating the redundancy of energy in the study extent. However, heterogeneity is more important for determining seed plant distributions. Pteridophyte and seed plant richness is strongly correlated, even after the environmental effects have been removed, implying functional linkages between them. Our study {3.lights the importance of incorporating biological traits of different taxonomic groups into the studies of macroecology and global change biology.

关键词： habitat heterogeneity pteridophytes seed plants species richness water-energy hypothesis.

New evidence for lack of CMB power on large scales

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Science china(Physics,Mechanics & astronomy) 2010年第3期53卷 567-570页

作者： LIU Hao1 & LI TiPei1,2,3.1 key laboratory of particle {3.physics, institute of high energy Physics, chinese academy of sciences, beijing 100049, china 2 Department of Physics & Center for {3.physics, Tsinghua University, beijing 100084, china 3.Department of Engineering Physics & Center for {3.physics, Tsinghua University, beijing 100084, china key laboratory of particle {3.physics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Department of Physics & Center for astrophysics Tsinghua University Beijing China Department of Engineering Physics & Center for astrophysics Tsinghua University Beijing China

A digitalized temperature map is recovered from the first light sky survey image published by the Planck team, from which an angular power spectrum of the cosmic microwave background (CMB) is derived. The amplitudes of the low multipoles (low-l) measured from the preliminary Planck power spectrum are significantly lower than those reported by the WMAP team. Possible systematical effects are far from enough to explain the observed low-l differences.

关键词： cosmology cosmic microwave background data analysis

Simulation of aerodynamic performance affected by vortex generators on blunt trailing-edge airfoils

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Science china(Technological sciences) 2010年第1期53卷 1-7页

作者： YANG Ke1,2,ZHANG Lei1,3.& XU JianZhong1,2 1 institute of Engineering Thermophysics,chinese academy of {3.,beijing 100190,china 2 key laboratory of Wind energy Utilization,chinese academy of {3.,beijing 100190,china 3.Graduate School of chinese academy of sciences,beijing 100190,china institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China key laboratory of Wind energy Utilization Chinese Academy of Sciences Beijing China Graduate School of chinese academy of sciences Beijing China

An investigation was carried out by numerical simulation on a wind turbine airfoil and a blunt trailing-edge airfoil with and without vortex generators (VGs), and the performance of the airfoils was analyzed. By the simulation of airfoil DU 91-W2-250 it was verified that the numerical method and model were credible. Based on this airfoil, a new one with a blunt trailing edge of 6% chord was blended by symmetrically adding thickness, and its characteristics curves were obtained through computing at key angles of attack. Additionally, the pressure distribution on blended airfoil was analyzed by comparing to the airfoil without blend. The interaction of streamwise vortices induced by VGs with trailing vortex or separation vortex was considered, followed by the uncovery of how VGs can suppress the boundary layer separation.

关键词： vortex generators airfoil blunt trailing-edge

Deprojection technique for galaxy cluster considering the point spread function

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Science china(Physics,Mechanics & astronomy) 2010年第S1期53卷 183-186页

作者： WANG YuSa,JIA ShuMei & CHEN Yong key laboratory for particle {3.physics,institute of high energy Physics,chinese academy of sciences,beijing 100049,china key laboratory for particle {3.physics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

We present a new method for the analysis of Abell 183. observed by *** method is a combination of the Direct Demodulation technique and *** eliminate the effects of the point spread function(PSF) with the Direct Demodulation *** then use a traditional deprojection technique to study the properties of Abell *** to only using a deprojection method,the central electron density derived from this method increases by 3.%,while the temperature profile is similar.

关键词： PSF Direct Demodulation deprojection Abell 183. galaxy cluster XMM-Newton