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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, 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 Astrophysics 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

Assessment of Dust Aerosol Optical Depth and Shortwave Radiative Forcing over the Northwest Pacific Ocean in Spring Based on Satellite Observations

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Atmospheric and Oceanic Science Letters 2009年第4期 223-228页

作者： CHEN Lin 1,2,SHI Guang-Yu 1,ZHONG Ling-Zhi 3.and TAN Sai-Chun 1 1 state key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics,Chinese Academy of Sciences,{3. 100029,china 2 key laboratory of Radiometric Calibration and Validation for Environmental Satellites (KLRCV),National Satellite Meteorology Center,china Meteorological Administration (NSMC/CMA),{3.,100081,china 3.state key laboratory of Severe {13.,Chinese Academy of Meteorological Sciences,{3. 100081,china state key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical FluidDynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beo＇ing 100029 China key laboratory of Radiometric Calibration and Validation for Environmental Satellites （KLRCV） National Satellite Meteorology Center China Meteorological Administration （SMC/CMA） Beijing 100081 China state key laboratory of Severe {3. Chinese Academy of Meteorological Sciences Beijing 100081 China

Dust aerosol optical depth (AOD) and its ac-companying shortwave radiative forcing (RF) are usually simulated by numerical ***,by using 9 months of Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol product data in combination with Clouds and the Earth’s Radiant Energy System Single Scanner Footprint (CERES/SSF) data,dust AOD and its shortwave RF were estimated over the cloud-free north-west (NW) Pacific Ocean in the springs of 2004,2005,and *** results showed that in this region,the mean dust AOD and its shortwave RF were 0.10 and 5.51 W m 2,*** order to validate the dust AOD de-rived by MODIS,results from the Goddard Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) model were also used *** correlation coefficient between the monthly averaged dust AOD derived by MODIS measurements and the model simulation results was approximately *** the estimates of the dust AOD and its shortwave RF obtained in this study are based mainly on satellite data,they offer a good reference for numerical models.

关键词： dust aerosols optical depth shortwave radiative forcing northwest Pacific satellite measurements

Statistical analysis of solar EUV and X-ray flux enhancements induced by solar flares and its implication to upper atmosphere

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Statistical analysis of solar EUV and X-ray flux enhancement...

Synthesis and Crystal Structure of [Cis-1,10phenanthroline-palladium（Ⅱ）(THF)2]dinitrate （THF = Tetrahydrofuran）

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Huijun Le,~(1,2) Libo Liu,~1 Han He,~3.and Weixing Wan~1 1 beijing National Observatory of space Environment,Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing,{3.. 2Also at state key laboratory of space weather,Center for space Science and Applied Research,Chinese Academy of Sciences,beijing, china. 3.key laboratory of Solar Activity,National Astronomical Observatories, Chinese Academy of Sciences,beijing,{3..

[1]The 0.1-0.8 nm X-ray flux data and 26-3. nm EUV flux data are used to statistically analyze the relationship between enhancement in X-ray flux and that in EUV flux during solar flares in *** EUV enhancement does not linearly increase with X-ray flux from C-class to X-class *** uprising amplitude decreases with X-ray *** correlation coefficients between enhancements in EUV and X-ray flux for X,M and C-class flares are only 0.66,0.58 and 0.54,respectively,which suggests that X-ray flux is not a good index for EUV flux during solar ***,for studying more accurately solar flare effect on the ionosphere/thermosphere system,one needs to use directly EUV flux *** of important reasons for depressing relationship between X-ray and EUV is that the central meridian distance(CMD) of flare location can significantly affect EUV flux variation particularly for X-class flares:the larger value of CMD results in the smaller EUV ***,there are much smaller CMD effects on EUV enhancement for M and C-class *** solar disc images from SOHO/EIT are utilized to estimate the percentage contribution to total EUV enhancement from the flare region and from other *** results show the larger percentage contribution from other region for the weaker flares,which would reduce the loss of EUV radiation due to limb location of flare and then weaken the CMD effect for weaker flares like M and C-class.

关键词：

来源： cnki会议评论

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Chinese Journal of Structural Chemistry 2003年第5期 548-550页

作者： HUANG Hui YU Shu-Yan② (state key laboratory of Polymer Physics and Chemistry, Joint laboratory of Polymer Science and Materials, Institute of Chemistry, The Chinese Academy of Sciences, {3. 100080, china)

A mononuclear complex, cis-1,10-phenanthroline-palladium(Ⅱ)(THF)2]dinitrate (THF = tetrahydrofuran) [Pd(C10H8N2)(C4H8O)2](NO3.2 1, has been prepared and structurally characterized by single-crystal X-ray diffraction. The crystal belongs to monoclinic system, space group P21/c with a = 7.881(1), b = 27.3.1(3., c = 10.178(1) ? ?= 103.3.3.3.? V = 213..5(4) 3. Mr = 554.83. Dc = 1.725 g/cm3. Z = 4, F(000) = 1128 and (MoK) = 0.926 mm-1. The structure was refined to R = 0.0678 and wR = 0.1651 for 1687 observed reflections with I > 2(I). It is revealed that the central Pd(Ⅱ) ion in the title complex is bonded to two THF and two phenanthroline molecules in a cis-configuration to form the coordination geometry, deviating slightly from the square plane.

关键词： crystal structure Pd(Ⅱ) complex 1 10-phenanthroline

Changes in the spatial scale of beijing UHI and urban development

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Science china Earth Sciences 2005年第Z2期48卷 116-127页

作者： YU Shuqiu, BIAN Lingen & LIN Xuechun state key laboratory on Severe {3., Chinese Academy of Meteorological Sciences, {3. 100081, china National Climate Center, china Meteorological Administration, {3. 100081, china state key laboratory on Severe {3. Chinese Academy of Meteorological Sciences Beijing 100081 China National Climate Center China Meteorological Administration Beijing 100081 China

The seasonal and interannual variations of beijing urban heat island (UHI) are investigated in this paper using the temperature data from 1960 to 2000 at 20 meteorological stations in the beijing region, and then the relationship between the intensity and spatial scale of UHI and beijing urbanization indices is analyzed and discussed. Main conclusions are the followings. First, beijing UHI shows obvious seasonal variations, and it is strongest in winter, next in spring and autumn, and least in summer. The seasonal variation of the UHI mainly occurs in the urban area. The UHI intensity at the center of beijing is more than 0.8℃ in winter, and only 0.5℃ in summer. Second, the intensity of beijing HUI exhibits a clear interannual warming trend with its mean growth rate (MGR) being 0.3.88℃/10 a. The MGR of HUI is largest in winter, next in spring and autumn, and least in summer, and the urban temperature increase makes a major contribution to the growth of HUI intensity. Third, since the Reform and Opening, the urbanization indices have grown several ten times or even one hundred times, the intensity of HUI has increased dramatically, and its spatial scale also expanded distinctively along with the expansion of urban architectural complexes. Fourth, the interannual variation of urbanization indices is very similar with that of HUI intensity, and their linear correlation coefficients are significant at a more than 0.001 confidence level.

关键词： beijing region, temperature change, heat island effect, HUI spatial scale, human activities.

Synthesis,Crystal Structure, Thermal Decomposition and Sensitivity Properties of (AIM)(HTNR) and (AIM)(PA)

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Chemical Research in Chinese Universities 2012年第1期28卷 4-8页

作者： TANG Zhan, YANG Li, QIAO Xiao-jing, WU Bi-dong, ZHANG Tong-lai, ZHOU Zun-ning and YU Kai-bei state key laboratory of Explosion Science and Technology, {3. Institute of Technology, {3. 100081, P. R. china beijing Institute of Technology State Key Laboratory of Explosion Science and Technology Beijing 100081

Two new energetic compounds （AIM）（HTNR） and （AIM）（PA）（AIM=2-azidoimidazole, TNR=2,4,6-trini troresorcinol, PA=picric acid） have been prepared by AIM（2-azidoimidazolium） and TNR（2,4,6-trinitroresorcinol） or PA（picric acid） and characterized by elemental analysis and FTIR spectrum. Their crystal structures were determined by X-ray single-crystal diffraction analysis. The obtained results show that （AIM）（HTNR） crystal belongs to monoc linic, P21/c space group, a=1.13.6（2） nm, b=0.703.5（14） nm, c=1.73.8（4） nm, β=106.91°, V=1.3.3.（5） nm3. Dc=1.778 g/cm3. Z=4, R1=0.0524, wR2[I 〉2σ（I）]=0.1067 and S=1.092 and （AIM）（PA） crystal belongs to monoclinic P21/c space group, a=0.803.3.16） nm, b=0.813.5（16） nm, c=2.0471（4） nm, β=93.93.3.°, V=1.3.49（5） nm3. Dc=1.683.g/cm3. Z=4, R1=0.0784, wR2[I〉2σ（I）]=0.1814 and S=1.098. Both the compounds have electrostatic attraction and hy drogen bonds, which contribute to making the constructions more stable. The decomposition of the two compounds was studied via differential scanning calorimetry（DSC） and thermogravimetry-derivative thermogravimetry（TG-DTG） techniques at a heating rate of 10 oC/min, and the results show that both the compounds underwent one intensive exothermic decomposition stage. Sensitivity tests reveal that the title compounds were insensitive to friction and im pact and sensitive to flame and could be applied in potential pyrotechnics.

关键词： 2-Azidoimidazolium 2,4,6-Trinitroresorcinol Picric acid Crystal structure Thermal decomposition

Monitoring Glacier and Supra-glacier Lakes from space in Mt. Qomolangma Region of the Himalayas on the Tibetan Plateau in china

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Journal of Mountain Science 2009年第3期6卷 211-220页

作者： YE Qinghua ZHONG Zhenwei KANG Shichang Alfred Stein WEI Qiufang LIU Jingshi key laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences (CAS) Beijing 100085 China state key laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China International Institutefor Geo-Information Science and Earth Observation (ITC) PO Box 67500 AA Enschede The Netherlands

Because of the large number and remoteness, satellite data, including microwave data and optical imagery, have commonly been used in alpine glaciers surveys. Using remote sensing and Geographical Information System （GIS） techniques, the paper presents the results of a multitemporal satellite glacier extent mapping and glacier changes by glacier sizes in the Mt. Qomolangma region at the northern slopes of the middle Himalayas over the Tibetan Plateau. Glaciers in this region have both retreated and advanced in the past 3. years, with retreat dominating. The glacier retreat area was 3.23.km2 （or o.75 km^2 yr^-1 during 1974 and 1976, 8.68 km^2 （or 0.3. km^2 yr^-1 during 1976 and 1992, 1.44 km^2 （or 0.12 km^2 yr^-1） during 1992-2ooo. 1.14 km^2 （or 0.22 km^2 yr^-1 during 2000-2003. and 0.52 km^2 （or 0.07 km^2 yr^-1 during 2003.2008, respectively. While supra-glacier lakes on the debris-terminus of the Rongbuk Glacier were enlarged dramatically at the same time, from 0.05 km^2 in 1974 increased to 0.71 km^2 in 2008, which was more than 13.times larger in the last 3. years. In addition, glacier changes also showed spatial differences, for example, glacier retreat rate was the fastest at glacier termini between 5400 and 5700 m a.s.l than at other elevations. The result also shows that glaciers in the middle Himalayas retreat almost at a same pace with those in the western Himalayas.

关键词： Glacier lake Remote Sensing Mr. Qomolangma region Himalayas Tibetan Plateau

Global view of Hopf bifurcations of a van der Pol oscillator with delayed state feedback

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Science china(Technological Sciences) 2010年第3期53卷 595-607页

作者： ZHANG Li1,WANG HuaiLei1 & HU HaiYan1,2 1 MOE key Lab of Mechanics and Control of Aerospace Structures,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,china 2 School of Aerospace Engineering,beijing Institute of Technology,beijing 100081,china MOE key Lab of Mechanics and Control of Aerospace Structures Nanjing University of Aeronautics and Astronautics Nanjing China School of Aerospace Engineering Beijing Institute of Technology Beijing China

This paper presents both analytical and numerical studies on the global view of Hopf bifurcations of a van der Pol oscillator with delayed state *** on a detailed analysis of the stability switches of the trivial equilibrium of the system,the stability charts are given in a parameter space consisting of the time delay and the feedback *** center manifold reduc-tion and the normal form method are used to study Hopf bifurcations with respect to the time *** gain an insight into the persistence of a Hopf bifurcation as the time delay varies farther away from its critical value,the method of multiple scales is used to obtain the global view of Hopf bifurcations with respect to the time *** the analytical results of Hopf bifurca-tions and global view of those bifurcations are validated via a collocation scheme implemented on *** most important discovery in this paper is the well-structured global view of Hopf bifurcations for the system of concern,showing the generality of the persistence of Hopf bifurcations.

关键词： Hopf bifurcation global view center manifold reduction method of multiple scales collocation scheme

The structural analysis of fuzzy measures

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Science china(Information Sciences) 2011年第1期54卷 38-50页

作者： ZHANG Ling1,ZHANG Bo2 & ZHANG YanPing1 1 Computer Science College,Anhui University,Hefei 23.03.,china 2state key Lab of Intelligent Technology & Systems Tsinghua National Lab for Information Science & Technology Information Science & Technology College,Computer Science & Technology,Tsinghua University,{3. 100084,china Computer Science College Anhui University Hefei China state key Lab of Intelligent Technology & Systems Tsinghua National Lab for Information Science & Technology Information Science & Technology College Computer Science & Technology Tsinghua University Beijing China

From quotient space based granular computing theory we explore the fuzzy measures of fuzzy sets. Based on the structural analysis of fuzzy sets,we present an"isotropism"*** this assumption we achieved the following insights:(1)the uniqueness of a fuzzy measure being isotropic on a finite complete semi-ordered set;(2)the necessary and suffcient condition of the isomorphism for fuzzy measure functions in fuzzy mathematics;(3.the necessary and suffcient condition that fuzzy measures have fuzzy and granular monotonicity;(4)under a certain assumption,the analytic expression for fuzzy *** results clarify the relationship between fuzzy measures and granular computing,reveal the essence of fuzzy measures,and provide a simple way of constructing fuzzy measures.

关键词： quotient space fuzzy set fuzzy measure rough set structural analysis