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An efficient and adaptive approach for modeling gravity effects in spherical coordinates

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An efficient and adaptive approach for modeling gravity effe...

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： Zhiwei Li~*,Tianyao Hao,Ya Xu,Yi Xu Key Laboratory of Petroleum Resources Research,institute of geology and Geophysics,{2. academy of sciences,beijing,10002.,China

The need to obtain more reliable Earth structures has been the impetus for conducting joint inversions of disparate geophysical *** seismic arrival time tomography,joint inversion of arrival time and gravity data has become an important way to investigate velocity structure of the crust and upper ***, the absence of an efficient approach for modeling gravity effects in spherical coordinates limits the joint tomographic analysis to only local *** order to extend the joint tomographic inversion into spherical coordinates,and enable it to be feasible for regional studies,we develop an efficient and adaptive approach for modeling gravity effects in spherical coordinates based on the longitudinal/latitudinal grid *** complete gravity effects of spherical prisms,including gravitational potential,gravity vector and tensor gradients,are calculated by numerical integration of the Gauss-Legendre quadrature(GLQ).To ensure the efficiency of the gravity modeling,spherical prisms are recursively subdivided into smaller units according to their distances to the observation *** approach is compatible with the parameterization of regional arrival time tomography for large areas,in which both the near- and far-field effects of the Earth’s curvature cannot be ***,this approach can be implemented into the joint tomographic inversion of arrival time and gravity data *** practical applications,the complete gravity effects of a single anomalous density body have been calculated,and the gravity anomalies of two tomographic models in the Taiwan region have also been obtained using empirical relationships between P-wave velocity and density.

关键词： Gravity effects Spherical coordinates Gauss-Legendre quadrature Joint inversion Tomography

A New Kind of Social Network and Its Application in Text Mining

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A New Kind of Social Network and Its Application in Text Min...

第四届全国信息检索与内容安全学术会议

作者： Weijie YANG~+ Ruwei DAI~+ Xia CUI institute of Automation,chinese {2. of sciences,beijing 100190,China

Social networks have recently attracted much attention for their importance to the Semantic *** paper proposed a content analysis based method for automatic obtaining social networks among various entities from chinese news stories.A new social network is defined,which is a kind of directed graph composed by named entities,relationship directions and relationship *** kind of social network can provide new thoughts and methods for other related researches in the field of text *** this paper,the applications of social network in relationship orientation analysis and automatic summarization are introduced.A series of experiments indicate that our method works well.

关键词： Social Network Main Verb Recognition Relationship Orientation Automatic Text Summarization.

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清初程朱理学“复兴”标志论略

史学集刊 2009年第5期 44-51页

作者：朱昌荣中国社会科学院历史研究所北京100732

程朱理学推动了清初伦理道德体系和社会秩序的重建,也在这一过程中于康熙中叶前后实现了自身"复兴"。其标志主要包括:在意识形态领域独尊地位的重新确立,在社会观念上获得广泛接受,以及编纂理学学术史著作热潮的兴起。

关键词：清初康熙中叶程朱理学

Insight into craton evolution:Constraints from shear wave splitting in the North China Craton

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Insight into craton evolution:Constraints from shear wave sp...

中国科学院地质与地球物理研究所2.08学术年会

作者： Liang Zhao~*,Tianyu Zheng,Gang L(u|¨) Seismological Laboratory(SKL-LE),institute of geology and Geophysics,{2. academy of sciences,beijing 10002.,China

The multi-episodic tectonic activities from the Precambrian to Cenozoic,including nucleus formation, cratonic amalgamation,and rejuvenation,make the North China Craton(NCC) an ideal natural laboratory for studying craton *** change in the upper deformation records is an important aspect for understanding cratonic formation and *** this study,we performed seismic shear wave splitting analysis using SKS phases from 50 portable *** different methodologies,shear wave splitting measurement and amplitude analysis of transverse/radial components,produced mutually consistent splitting *** results showed that the seismic anisotropy beneath the Ordos Block can be divided into three subgroups reflecting the tectonic *** these results with those from previous splitting studies in the eastern NCC,we suggest that the Proterozoic amalgamation generated the seismic anisotropy in the boundary zone between the Ordos Block and the Trans-North China Orogen, while the anisotropy in the eastern Trans-North China Orogen and eastern NCC were possibly associated with the lithospheric rejuvenation during the Late Mesozoic to Cenozoic.

关键词： North China Craton Upper mantle Seismic anisotropy Shear wave splitting

Retrospect and prospect: advances and future strategies in climate research

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Progress in Natural Science:Materials International 2003年第4期 3-8页

作者： YE Duzheng and LU Jianhua(institute of Atmospheric Physics, chinese {2. of sciences, beijing 10002., China) A visiting scholar in Department of Meteorology, University of Hawaii institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China A visiting scholar in Department of Meteorology University of Hawaii

A brief review of the progress in climate research and a prospect on its further development in the 2.st century is pre-sentcd. Some key findings including the eoncept of climate system, the discovery of climatic multi-equilibrium and abrupt climate changes, and the recognition of human activities as an important force of climate change made breakthroughs in climatologv possible during last few decades. The adaptation to climatic and global change emerged as a new aspect of climatic research during the 1990s. Climate research will break through in the observation of the global system, in the analysis of mass data, in the deepening of research on the mechamsm of climatic change, and in the improvement of models. In the applied fields of climate research, there will be substantial progress in the research on adaptation to global change and sustainable development, on orderly human activities, and climate modification.

关键词： advances climate system global change abrupt climate change orderly human activity.

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声空化物理研究和核发射实验的近期进展

物理 2002年第8期31卷 490-495页

作者：应崇福中国科学院声学研究所北京100080

简要概述了 2.0世纪 2.0年代起多泡声空化的发现、研究和应用 .随后重点介绍了 2.0世纪 90年代初实现的稳态单一气泡 ;由于它的实现 ,对声空化的实验研究和理论研究迅速取得进展 ,特别是在对气泡内部的极端条件(高温、高压、高密度 )以... 详细信息

简要概述了 2.0世纪 2.0年代起多泡声空化的发现、研究和应用 .随后重点介绍了 2.0世纪 90年代初实现的稳态单一气泡 ;由于它的实现 ,对声空化的实验研究和理论研究迅速取得进展 ,特别是在对气泡内部的极端条件(高温、高压、高密度 )以及对气泡内声致发光的机理研究方面 .同时还介绍了我国早在 2.0世纪 6 0年代实现的瞬态单一泡以及近期的一些实验结果 .文章最后提到 2.0 0 2. 3月美国报道的声空化核辐射实验。

关键词：核发射实验声空化多泡稳态单泡瞬态单泡尾流

Geochemistry of UHP metamorphic rocks from the CCSD-main hole （0 - 2.50 m）, Sulu orogenic belt, Eastern China

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Geochemistry of UHP metamorphic rocks from the CCSD-main hol...

2.04年全国岩石学与地球动力学研讨会

作者： Zhang Zeming, Xu Zhiqin and Liu Fulai~1, Xiao Yilin~2. Liou J G ( Dept. of geological and Environmental sciences, Stanford University) and Jahn Bor-ming~3 (1. {2. of geology, CAGS, beijing 100037 2. Geoscience Center, Geottingen University 3. Department of Geosciences, National Taiwan University)

＜正＞ The chinese Continental Scientific Drilling （CCSD） located near Maobei village, about 17 km southwest of Donghai, is targeted to drill a 5000-meter-deep main hole penetrating a tectonic slab of UHP metamorphic rocks. This project provides an advantageous and rare chance of collecting UHP rock samples continuously from the subsurface. The 0-2.50 m of the CCSD-main hole consists of eclogite, orthogneiss, paragneiss, ultramafic rock and minor schist and quartzite. Eclogites are the principal lithological type, and mainly occur at

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Synthesis, Growing Processes and Physical Properties of CdS Nanoclusters in Y-Zeolite Studied by Positron Annihilation

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Wuhan University Journal of Natural sciences 2000年第4期5卷 431-435页

作者： Peng Hao,Ma Li, Wang Shao-jie, Liu Shu-man, Lin Zhao- jun Department of Physics, Wuhan University, Wuhan 430072. China institute of Semiconductor, chinese {2. of Science, beijing 100086, China Department of Physics Wuhan University Wuhan China institute of Semiconductor Chinese Academy of Science Beijing China

Direct synthesis of CdS nanoclusters within the pore structure of Y zeolite was made. The location of CdS nanoclusters inside Y zeolite hosts was confirmed by the blue-shifted reflection absorption spectra with respected to that of bulk CdS materials. In this paper, we conducted Positron Annihilation Lifetime Spectrum (PALS) measurements on a series of CdS/Y zeolite samples and concluded that CdS clusters were not located in supercages but in smaller sodalite cages; as the CdS loading concentration increases to 5 wt%, the discrete CdS cubes begin to form bigger superclusters through interaction. The stability of CdS clusters inside the sodalite units is due to the coordination of Cd atoms with the framework oxygen atoms of the double six-ring windows. Moreover, PALS reveals some important information of surface states existing on the interfacial layers between CdS clusters and Y zeolite.

关键词： Y zeolite nanoclusters absorption spectrum positron annihilation surface states interfacial layers

The Intrinsic Factors Causing the Significant Differences in Mesozoic Mineralization Between Jiaodong anf Luxi Areas

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The Intrinsic Factors Causing the Significant Differences in...

中国科学院地质与地球物理研究所2.02.术年会

作者： Xu Guizhong~a Zhou Rui~b Wang Yifen~a She Hongquan~c Libing~d Du Beriming~e Song Minchun~e a.institute of geology and Geoshys cs,{2. academy of Siences,beijing 10002. b.Exploration and Production Research institute,China Petroleum and Chemical Corporation,beijing 100083 c.institute of Mineral Resources,Chiese academy of geological sciences,beijing {12. d.institute of No.3 geological Prospecting,Shandong province,Yantai 2.4000 e.institute of No.4 geological Prospection,shandong Province,Weifanf 2.102.

Jiaodong and Luxi areas are separated by Yishu *** two areas were put together at the end of Middle Jurassic owing to the Large-scale sinistral translative motion of Tan-Lu *** mineralization of gold -polymetallic ore deposits in the above two areas took place in the Early *** there are the significant differences in mitallogenic scale,the ore deposit types and metallogenic mechnisin between Jiaodong and Luxi areas.A comparative study shows that Luxi area is located within the North China Plate and Jiaodong area in the margin of the North China Plate for a long *** should be pointed out that Jiaodong area had undergone following complex tectonic environments and geological prosess:the Precambrian complex geological process,The Early Palaeozoic oceanic-continental crustal subduction anf collision orogeny,the Late Palaeozoic slow uplift,the continental-continental crustal subduction and intensive compression from Late Indosinian to early Yanshan periods,as well as the Late Yanshan lithosphyre thinning and large-scale tectonic magmatic *** is proposed that the subduction of the Kula-Pacific Plate beneath the Euro-Asia Plate and the intensive activities of Tan-Lu fault zone are the important dynamic conditions resulted directly in sudden occurrence of large-scale mineralization in the Early Cretaceous in Jiaodong area besides the above comprehensive geological structural factors.

关键词： Jiaodong and Luxi areas Yishu fault zone Mesozoic Tectonic-magmatic activity Mineralization Dynamic background