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Disk Wave and Gas Dynamics around Galactic Black Holes

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Disk Wave and Gas Dynamics around Galactic Black Holes

黑洞物理研讨会

作者： Yu-Qing Lou Physics Department, The Tsinghua Center for Astrophysics, Tsinghua university, beijing 100084, china National Astronomical Observatory, chinese academy of sciences, Road Datun, 20A, beijing, 100012, china Department of Astronomy and Astrophysics, The university of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA.

We present physical ideas on two astrophysical problems, both are suggested to involve gravitationally induced disk wave and gas dynamics around supermassive black holes (SMBHs) at galactic centers. The first problem concerns the mechanism for circumnuclear starburst rings on kiloparsec (kpc) scales in Seyfert galaxies. Large-scale spiral or barred galactic structures can gravitationally excite fast magnetohydrodynamic (MHD) density waves at the modified inner Lindblad resonance (mILR) of a central magnetized gas disk. An effective damping of such sustained waves will persistently reduce the disk angular momentum and lead to a ringlike accumulation of materials and magnetic fluxes within the mILR which, at a critical phase, becomes vulnerable to massive star formation on smaller scales. There may be several outcomes for central activities of Seyfert galaxies: (1) a very luminous starburst ring with a less active nucleus for a very strong wave damping;(2) a moderate starburst ring with a moderately active nucleus for an intermediate wave damping;and (3) a prominent active galactic nucleus with a weaker starburst ring for an extremely weak circumnuclear wave damping on kpc scales. The second problem is on the origin of double periodicities at the center of our Galaxy - the Milky Way. We develop a scenario that involves an effective mass point (EMP;hypothesized to be a black hole) with a mass of - 4000M⊙and a radial location of - 2000R S (R S is the Schwarzschild radius of the SMBH) orbiting around the central SMBH at Sagittarius A* and the density wave dynamics of a thin accretion disk. The shorter periodicity corresponds to that of two-armed spiral density waves that are sustained at a relevant ILR and travel sufficiently inward (-100R S) towards the center;and the longer periodicity corresponds to that of the SMBH orbiting about the center of mass of the SMBH and EMP system. In this scenario, variations of the two periodicities are related to the outward migration o

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Syntheses,Crystal Structure,and Characterizations of Polysulfide Compound:Ba4Sb4S11

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Syntheses,Crystal Structure,and Characterizations of Polysul...

中国化学会第六届全国结构化学学术会议

作者： Zhong-Zhen Luo,Chen-Sheng Lin,Hao Zhang,Wei-Long Zhang, Wen-Dan Cheng~* State Key Laboratory of Structural Chemistry,Fujian Institute of Research on the Structure of Mater,the chinese academy of sciences,Fuzhou,Fujian 350002. graduate School of the chinese academy of sciences,beijing,100039.

Ternary Ba-Sb-S systems have been well studied and many compounds,including BaSbS,BaSbS, etc.,have been synthesized over the past 30 *** these compounds,as there are no S-S bonds in the structures,the oxidation state of all S atoms is 2-.The ternary polysulfide compound,BaSbS,was synthesized by using a conventional high-temperature solid-state reaction method in evacuated quartz tubes.

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A new synonym of Pedicularis cyathophylla(Orobanchaceae)

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Journal of Systematics and Evolution 2011年第5期49卷 507-507页

作者： 1,2~Wen-Bin YU 1,2~Pan-Hui HUANG 1~Hong WANG 1(Key Laboratory of Biodiversity and Biogeography,and Plant Germplasm and Genomics Center,Kunming Institute of Botany,chinese academy of sciences,Kunming 650204,china) 2(graduate university of chinese academy of sciences,beijing 100049,china) (Key Laboratory of Biodiversity and Biogeography and Plant Germplasm and Genomics Center Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China) (graduate university of chinese academy of sciences Beijing 100049 China) *Correspondence: Hong WANG *Correspondence: E-mail: wanghong@*** Tel.: 86-871-5223534 Fax: 86-871-5217791.

Pedicularis cyathophylla Franchet in Bull. Soc. Bot. France 47: ***: china. Sichuan: Kangding, Zheduoshan Mountains(Ta-tsien-kou & Tche-to-chan), J. A. Soulie′ 218 (holotype,P00160827, P!).Pedicularis xiangchengensis... 详细信息

关键词： PE A new synonym of Pedicularis cyathophylla Orobanchaceae

RESEARCH ON BIOLOGICAL INVASIONS IN china

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RESEARCH ON BIOLOGICAL INVASIONS IN CHINA

International Congress on Biological Invasions

作者： Fang-Hao WAN~1,Jian-Ying GUO~1,and Feng ZHANG~2 1 State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,chinese academy of Agricultural sciences,beijing 100094,china, 2 MoA-CABI Joint Laboratory for Bio-safety Institute of Plant Protection,chinese academy of Agricultural sciences,beijing 100094,china

With booming economy and international trade,china faces growing threats from biological *** are some 520 invasive alien species recorded to cause damages to different ecosystems in china,including 268 alien plants,193 alien animals and 61 alien *** dispersal of some invasive alien species has not only jeopardized local ecosystems,biodiversity and human health,but also high economic *** agriculture and forestry sectors,13 invasive alien insect pests and weeds have caused RMB 57.43 billion annual economic *** invasive alien species came to china during the period from 19 to 20 *** 54%of invasive alien species in china originated from North and South America,20% coming from other Asian countries and 17%coming from *** Component Analysis showed that successful invasions are mainly attributed to human activities,with the following factors of propagule pressure and climatic or habitat conditions. To meet the challenges from biological invasions,china has invested millions of dollars on basic and applied research in recent years to investigate invasion mechanisms,develop prevention and control technologies of invasive alien species, and establish Invasion Biology *** most comprehensive research and discipline framework has been set up by chinese scientists to guide the national research efforts in synergy,as well as a sound management strategy and core research *** date,basic research on invasive alien species in china has been focusing on their population establishment and expansion,ecological adaptation and evolution,and impacts on structures and functions of *** research has been focusing on technological innovation for prevention and management of invasive alien species,including database,detection and monitoring,early warning system,spread blocking and biological control *** findings and results of basic and applied research are summarized through case ***

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多词素词的通达表征:分解还是整体

心理科学 2000年第4期23卷 395-398页

作者：王春茂彭聃龄中国科学院心理研究所!100101 北京师范大学心理系!100875

有关通达表征的结构主要有三种观点 :词素、整词和混合的观点。分解存储的通达表征认为 ,在通达表征层次中只有不可再分的词素 ,而没有彼此独立的词条。也就是说 ,词语是以词素分解形式存储在通达表征中的。整词存储的通达表征认为 ,在... 详细信息

有关通达表征的结构主要有三种观点 :词素、整词和混合的观点。分解存储的通达表征认为 ,在通达表征层次中只有不可再分的词素 ,而没有彼此独立的词条。也就是说 ,词语是以词素分解形式存储在通达表征中的。整词存储的通达表征认为 ,在通达表征中存储的都是整词 ,每一个词都有其独立的词条。混合的通达表征认为词素和整词都有可能是通达表征中的单元。它具有更大的灵活性。综合考虑已有的文献和进一步的理解思考 ,作者提出影响词语通达表征的两个因素 :语义透明度和词频。

关键词：多词素词通达表征心理词典

Extrapolate well logs based on the constrained interpolation algorithm

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Extrapolate well logs based on the constrained interpolation...

中国科学院地质与地球物理研究所2008学术年会

作者： Liu Hongwei,Liu Hong,Qin Yueshuang,and Shou Hao 1.Institute of Geology and Geophysics,chinese academy of sciences,beijing 100029,china. 2.State Key Laboratory of Geological Processes and Mineral Resources,china university of Geosciences,beijing,100083 3.The Exploratory development Institute of Daqing Oilfield Limited Liability Company,Daqing 163712,china. 4.Research Institute of Exploration and Development of chinese Petroleum,beijing 100083,china.

Based on a detailed analysis of differences between seismic data and well logs, we discuss the problem of matching seismic traces and well logs and present a new matching method based on event search in instantaneous phase which greatly improves seismic *** method is based on flattening events in instantaneous phase to compare the seismic traces to the well log traces with the same *** calculate the coefficients using the singular value decomposition method to extrapolate the well *** a result,the events in the seismic profile are continuous and match well with well *** apply this method to the Mao-2 well in Daqing Oilfield with good results.

关键词： events flattening SVD method instantaneous phase correlation

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我国数字图书馆标准与规范的建设框架

图书情报工作 2003年第4期47卷 7-11,64页

作者：张晓林肖珑孙一刚陈凌刘炜中国科学院文献情报中心北京100080 北京大学图书馆北京100871 国家图书馆北京100081 CALIS管理中心北京100871 上海图书馆上海200031

在简要分析数字图书馆标准规范重要性和发展趋势的基础上,提出我国数字图书馆标准规范的长期目标和近期任务,描述标准规范发展战略、建设机制、核心标准规范体系的建设内容和要求。

关键词：数字图书馆标准规范发展战略建设机制核心标准规范体系

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LAKES IN THE MIDDLE KEKEXILI REGION

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Scientia Geologica Sinica 1994年第4期 479-486页

作者： Han Chunyu(Center for International Scientific Exchanges, chinese academy of sciences, beijing 100864)Murayama Haruta(Department of Chemistry, Faculty of Education, Yokohama National university, 156 Tokiwadai,Kodogaya-ku, Yokohama, Japan 240)

ＬＡＫＥＳＩＮＴＨＥＭＩＤＤＬＥＫＥＫＥＸＩＬＩＲＥＧＩＯＮＨａｎＣｈｕｎｙｕ（ＣｅｎｔｅｒｆｏｒＩｎｔｅｒｎａｔｉｏｎａｌＳｃｉｅｎｔｉｆｉｃＥｘｃｈａｎｇｅｓ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎｃｅｓ，Ｂ...

ＬＡＫＥＳＩＮＴＨＥＭＩＤＤＬＥＫＥＫＥＸＩＬＩＲＥＧＩＯＮＨａｎＣｈｕｎｙｕ（ＣｅｎｔｅｒｆｏｒＩｎｔｅｒｎａｔｉｏｎａｌＳｃｉｅｎｔｉｆｉｃＥｘｃｈａｎｇｅｓ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎｃｅｓ，Ｂｅｉｊｉｎｇ１００８６４）Ｍｕｒａ...

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A CPG-based Sensory Feedback Control Method for Robotic Fish Locomotion

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A CPG-based Sensory Feedback Control Method for Robotic Fish...

第三十届中国控制会议

作者： WANG Ming~1,YU Junzhi~2,TAN Min~2,ZHANG Guiqing~1 1.School of Information and Electrical Engineering,Shandong Jianzhu university,Jinan 250101,P.R.china 2.Laboratory of Complex Systems and Intelligence Science,Institute of Automation, chinese academy of sciences,beijing 100190,P.R.china.

＜正＞This paper deals with a Center Pattern Generator（CPG） centered sensory feedback control method for robotic fish locomotion,which improves the maneuverability and adaptability of robotic fish in water.A two-phase CPG-based control architecture to implement the autonomous locomotion in robotic fish has been *** whole process of the control architecture is divided into two phases:the upper decision-making and the automatic *** to the upper command from the controller and the sensory input,a proposed finite state machine algorithm determines locomotion gaits such as straight forward/backward,turning left/right,floating up/swimming down,and so on,and modify the coupling forms and controlling *** then,the CPG model with sensory feedback takes charge the autonomous locomotion *** sensory feedback control method can improve the adaptation of the system to environmental changes,external requirements, or proprioceptive *** experimental results validate the CPG-based sensory feedback control method, which can be extended to other robotic applications.

关键词： CPG Sensory Feedback Robotic fish Environmental sensing Swimming control