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The age of the plant fossil assemblage in the Liuqu Conglomerate of southern Tibet and its tectonic significance

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Progress in Natural Science:Materials International 2006年第1期16卷 55-64页

作者： FANG Aimin1, YAN Zhen1, LIU Xiaohan2, PAN Yusheng1, LI Jiliang1, YU Liangjun1, HUANG Feixing2 and TAO Junrong3.(1.Laboratory of Lithosphere Tectonic Evolution, institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, China 2. institute of Tibet Plateau Research, chinese academy of sciences, beijing 100085, China 3. institute of Botany, chinese A cademy of sciences, beijing 100093. China) Laboratory of Lithosphere Tectonic Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China institute of Tibet Plateau Research Chinese Academy of Sciences Beijing 100085 China institute of Botany Chinese A-cademy of Sciences Beijing 100093 China

The Liuqu Conglomerate, situated to the south of Yarlung Tsangbo Suture Zone (YTSZ), is a suit of molasse formed in a foreland basin of the Himalayan orogenic belt after the collision between the two plates of the Indian and Eurasion, It is of great significance in constraining the younger limit time of the collision of the two plates and providing stratigraphic evidence to reveal the post-colli sional tectonic evolution and uplifting history of the Tibet plateau. However, the age of this molasse suit and its correlation to other synchronous strata distributed in southern Tibet have been in great disputes for a long time. Especially in recent years, argues on its ages are growing violently with the recognition of the great sedimentary tectonic significances of this molasse. During the field work carried out recently on this molasse suit, a lot of plant fossils were found preserved in fairly good conditions in the upper part of this strata, which is of great help in determining its age. By identification, the assemblage of the plant fossils belongs to a tropic to subtropic flora developed in the southern margin of the Northern Hemisphere supercontinent during the Middle to Later Eocene, which can provide good constraint on its formation age. This paper is to give a brief introduction of the plant assemblage and its age, and to discuss their tectonic significances.

关键词： Liuqu conglomerate plant fossils age Eocene Tectonic implications.

Synthesis of a New Polysiloxane Containing Octaphenylcyclodisilazane

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chinese Chemical Letters 2000年第6期11卷 511-512页

作者： Ning ZHOU Zhi Jie ZHANG Cai Hong XU Ze Min XIE(center for Molecular Science, institute of chemistry, chinese academy of sciences.{3. 100080) chinese Acad Sci Ctr Mol Sci Inst Chem Beijing 100080 Peoples R China

A new polysiloxane containing octaphenylctclodisilazane was synthesized from the anionic polymerization of octamethylcyclotetrasiloxane (D-4) and 'seed solution' as initiator. which was prepared by hexamethylcyclotris... 详细信息

关键词： polysiloxane octaphenylcyclodisilazane synthesis

THE L^2-NORM ERROR ESTIMATE OF NONCONFORMING FINITE ELEMENT METHOD FOR THE 2ND ORDER ELLIPTIC PROBLEM WITH THE LOWEST REGULARITY

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Journal of Computational Mathematics 2000年第3期18卷 277-282页

作者： Lie-heng Wang (LSEC, institute of Computational Mathematics and Scientific/Engineering Computing, academy of Mathematics and System sciences,{3., beijing, 100080, China) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京 100080

Presents the abstract L...-norm error estimate of nonconforming finite element method. Use of the Aubin Nitsche Lemma in estimating nonconforming finite element methods; Details on the equations.

关键词： L-2-norm error estimate nonconforming f.e.m. lowest regularity

Formal Verification under Unknown Constraints

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Wuhan University Journal of Natural sciences 2005年第1期10卷 43-46页

作者： LI Guang-hui 1,2,3., LI Xiao-wei 2,3.. School of Information Engineering, Zhejiang Forestry College, Hangzhou 3.13.0, Zhejiang, China 2. institute of Computing Technology, chinese academy of sciences, beijing 100080, China 3. Graduate School of the chinese academy of sciences, beijing 10003., China School of Information Engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

Effective solutions to a global 3. visual system in networking environments

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Science China Earth sciences 2005年第11期48卷 2032-2039页

作者： ZHANG Liqiang1,2, ZHANG Yan3. YANG Chongjun2, LIU Suhong1, REN Yingchao2, RUI Xiaoping2 & LIU Donglin2 1. State Key Laboratory of Remote Sensing sciences, School of Geography and Remote Sensing, beijing Normal University, beijing 100875, China 2. State Key Laboratory of Remote Sensing sciences, institute of Remote Sensing Applications, chinese academy of sciences, beijing 101001, China 3. institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, beijing 101001, China 1. State Key Laboratory of Remote Sensing sciences School of Geography and Remote Sensing Beijing Normal University 100875 Beijing China 2. chinese academy of sciences State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications 101001 Beijing China 3. institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences 101001 Beijing China

The development of Web-based global 3. visual system has made progresses. However, there exist few mature and effective ways for managing, transmitting and visualizing massive spatial data. Based on the related work, the paper illustrates the ellipsoidal quadtree technique for rapid access multi-scale and multiple level geographical data, integrates the streaming with level-of-detail rendering method for transmitting the data on the network, and im-plements large-scale terrain surface simplification using M-band wavelet transforms and mul-tiresolution triangulations. We fulfil a web-based global terrain visual system using COM com-ponents on the basis of the above techniques. The system has a good prospect in the military simulation and city plans.

关键词： massive spatial data, streaming transmission, system architecture, M-band wavelet

Entropy of three-dimensional BTZ black holes

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中国科学：物理学、力学、天文学英文版 2004年第3期47卷 277-283页

作者： GAO Changjun1,2 & SHEN Yougen1,2,3.4 1.Shanghai Astronomical Observatory,chinese academy of sciences,Shanghai 20003.,China(mailing address) 2.National Astronomical Observatories,chinese academy of sciences,beijing 100012,China 3.institute of Theoretical Physics,chinese academy of sciences,beijing 100080,China 4.Shanghai United {13. for Astrophysics,Shanghai 20023.,China 1. Shanghai Astronomical Observatory Chinese Academy of Sciences 200030 Shanghai China 2. National Astronomical Observatories Chinese Academy of Sciences 100012 Beijing China 3. institute of Theoretical Physics Chinese Academy of Sciences 100080 Beijing China 4. Shanghai United center for Astrophysics 200234 Shanghai China

The entropies of scalar field and neutrino field are calculated in the background of three-dimensional BTZ black hole. Considering statistical physics,we propose not to consider the superraradiant modes for bosons (Fermion fields do not display supperradiance).In fact,the nonsuperradiant modes do contribute exactly the area entropy for both bosons and fermions. The result shows that the neutrino field entropy is 3.2 times the scalar one.

关键词： BTZ black holes, entropy, supperradiant modes.

HYDROPHOBICITY OF CONTAMINATED SILICONE RUBBER SURFACES

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chinese Journal of Polymer Science 2002年第6期20卷 559-564页

作者： Zhi-min Zheng Cai-hong Xu Jian Jiang Chang-yu Ren Wei Gao Ze-min Xie center for Molecular Science, institute of chemistry, chinese academy of sciences,{3., China chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

Silicone rubber (SIR) shows superior performance when used outdoors, but its surface can be transformed from inherently hydrophobic to hydrophilic by the adsorption of contaminants. Al(OH)(3., Al2O3. quartz powder and active carbon were selected as authentic contaminants. Hydrophobicity of the surface was determined using contact angle measurement. The results indicate that the adsorbability of the contaminants can strongly affect the hydrophobicity of contaminated SIR surface. The increasing rate of contact angle of specimens contaminated by Al(OH)(3. was much faster than that by Al2O3.and quartz due to the adsorption of migrated low molecular weight (LMW) polydimethylsiloxanes. Specimens contaminated by active carbon could achieve surface hydrophobicity within 15 min because active carbon has high adsorbability. Surfaces of contaminated ultrapure SIR, polytetrafluoroethylene (PTFE) and glass remain hydrophilic because they contain no mobile LMW components. The addition of oligomeric polydimethylsiloxanes has little effect on the hydrophobicity of contaminants covered on SIR surface.

关键词： hydrophobicity silicone rubber contact angle contamination

Physical mechanisms of plant roots affecting weathering and leaching of loess soil

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Science China Earth sciences 2006年第9期49卷 1002-1008页

作者： LI Yong1,2, ZHANG Qingwen1,2, WAN Guojiang3. HUANG Ronggui3. PIAO Hechun3. BAI Lingyu2 & LI Lu2 1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, institute of Soil and Water Conservation, chinese academy of sciences, Yangling 712100, China 2. institute of Agro-Environment and Sustainable Development,{3. academy of Agricultural sciences, beijing 100081, China 3. institute of Geochemistry, chinese academy of sciences, Guiyang 550002, China 1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling 712100 China 2. institute of Agro-Environment and Sustainable Development Chinese Academy of Agricultural Sciences Beijing 100081 China 3. institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Plant roots have potential impacts on soil mineral weathering and *** objective is to understand the physical mechanisms of plant roots affecting weathering andleaching of loess soil. Root densities were measured through the method of a large-size dug profile,and transport fluxes of soil elements were determined using an undisturbed monolith soilinfiltration device on the hilly and gully regions of the chinese Loess Plateau. The results showthat the improvement effects of soil environment by plant roots are mainly controlled by the densityand weight of the fibrous roots with the diameters less than 1 mm. Plant roots have the strongereffects on soil physical properties than chemical properties. The principal components analysis(PCA) indicates that soil physical properties by plant roots account for 56.7% of variations in soilenvironment whereas soil chemical properties and pH contribute about 24.2% of the soil *** roles of plant roots in controlling soil weathering and leaching increased in the followingorder: infiltration enhancement > increase of bio-active substance > stabilization of soilstructure. The effects of plant roots on soil mineral weathering and leaching can be quantifiedusing the multiple regression models with the high prediction accuracies developed in this study.

关键词： plant roots, soil weathering and leaching rates, soil environment field, principal components analysis (PCA), chinese Loess Plateau.

Synthesis of Methylated β-Cyclodextrins Derived Optically Active Poly(N-diphenylmethyl maleimide)

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chinese Chemical Letters 1997年第3期8卷 215-218页

作者： Wei Hong LIU Yong Ming CHEN Chuan Fu CHEN and Fu XI (institute of chemistry, chinese academy of sciences,{3. ) chinese ACAD SCI INST CHEMBEIJING 100080PEOPLES R CHINA

The methylated β-cyclodextrins derived optically active polymers are firs synthesized through asymmetric polymerization of N-diphenylmethyl maleimide with lithium salt of heptakis(2,6-O-dimethyl) β-cyclodextrin (DM-β-CD) as an initiator. The resulting polymers show negative specific rotation which is opposite in sign to that of DM-β-CD. The asymmetric induction is further confirmed by circular dichroism. The structure is characterized by IR and NMR spectroscopies

关键词： Cyclodextrins Derived Optically Active Poly Li Chen N-diphenylmethyl maleimide Synthesis of Methylated