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Relationships between tree-ring width index and NDVI of grassland in Delingha

chinese Science Bulletin 2006年第9期51卷 1106-1114页

作者： HE Jicheng1,3.& SHAO Xuemei1,21. institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, {3. 100101, china 2. institute of Tibetan Plateau Research, chinese academy of sciences, {3. 100085, china 3. Graduate School of chinese academy of sciences, {3. 10003., china institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Graduate School of chinese academy of sciences Beijing China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China

Using five well-replicated Qilian juniper (Sabina przewalskii Kom.) tree-ring width index se- ries, monthly normalized difference vegetation index (NDVI) of grassland, and climatic data from 1982 to 2001, the relationships between tree-ring width index, NDVI of grassland, and climatic data were analyzed firstly. Then, the relationship between tree-ring width index and NDVI of grassland was explored. The re- sults showed that: (1) Temperature and precipitation in June influenced tree-ring width index and NDVI of grassland deeply in Delingha. (2) There were sig- nificant relationships between five tree-ring width index series (DLH1-DLH5) and monthly NDVI of grassland from June to September, with the most significant relationship being between tree-ring width index series and NDVI of grassland in August. (3. The PC1 (the first principal component derived from DLH1-DLH5 series) exhibited good agreement with monthly NDVI of grassland in the grass growth sea- son (from June to September) and the averaged NDVI in the growth season, which was attributed to their common responses to water-supply limit in Delingha. This study may allow an increase in studying the past dynamics of grassland in Delingha in that the variation of grassland NDVI during the last millennium has been reconstructed from PC1.

关键词：圆柏祁连山 NDVI 草原年轮宽度指数

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ENHANCING GOLD EXTRACTION FROM COPPER BEARING ORES

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中国有色金属学会会刊：英文版 1995年第3期5卷 25-28页

作者： Deng, Tong Ma, Yun(institute of Chemical Metallurgy,chinese academy of {3., beijing 100080) chinese Acad of sciences Beijing China

ＥＮＨＡＮＣＩＮＧＧＯＬＤＥＸＴＲＡＣＴＩＯＮＦＲＯＭＣＯＰＰＥＲＢＥＡＲＩＮＧＯＲＥＳ￥Ｄｅｎｇ，Ｔｏｎｇ；Ｍａ，Ｙｕｎ（ＩｎｓｔｉｔｕｔｅｏｆＣｈｅｍｉｃａｌＭｅｔａｌｌｕｒｇｙ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆ... 详细信息

ＥＮＨＡＮＣＩＮＧＧＯＬＤＥＸＴＲＡＣＴＩＯＮＦＲＯＭＣＯＰＰＥＲＢＥＡＲＩＮＧＯＲＥＳ￥Ｄｅｎｇ，Ｔｏｎｇ；Ｍａ，Ｙｕｎ（ＩｎｓｔｉｔｕｔｅｏｆＣｈｅｍｉｃａｌＭｅｔａｌｌｕｒｇｙ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎｃｅｓ，Ｂｅｉｊｉｎｇ１...

关键词： Copper Gold Ammoniacal cyanidation

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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, institute of Physics, chinese academy of sciences,{3., china 3. BSRF, institute of High Energy Physics, chinese academy of sciences, beijing 10003., china 1. Key Laboratory of Metastable Materials Science and Technology Yanshan University 066004 Qinhuangdao China 2. Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 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.

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Accuracy of Multivariable Refinable Functions and Two-Scale Similarity Transform

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Acta Mathematica Sinica,English Series 2000年第2期16卷 271-276页

作者： Qiuhui Sheng Silong Peng institute of Mathematics,academy of Mathematics and Systems sciences,{3. academy of sciences,beijing 100080,P.R.china institute of Mathematics Academy of Mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100080 P. R. China

In this paper,we prove that if two multiresolutions satisfy a relation,then they have the same accuracy in the multivariate FSI case.

关键词： Accuracy Symbol function Two-scale similarity transform

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COPOLYMERIZATION OF ETHYLENE AND PROPYLENE WITH (CpCH_2CH_2CH=CH_2)_2MCl_2(M=Zr,Hf)AND Cp_2ZrCl_2 CATALYSTS

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chinese Journal of Polymer Science 2000年第2期18卷 169-175页

作者： Hui Yao Shi-jing Xiao institute of Chemistry, chinese academy of sciences, beijing 100080,{3. chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

(CpCH_2CH_2CH = CH_2)_2MCl_2(M=Zr, Hf)/MAO and Cp_2ZrCl_2/MAO (Cp=cyclopentadienyl; MAO=methylaluminoxane) catalyst systems have been compared for ethylene copolymerization to investigate the influence of theligand and transition metal on the polymerization activity and copolymer properties. For both CH_2CH_2CH=CH_2 substitutedcatalysts the catalytic activity decreased with increasing propene concentration in the feed. The activity of the hafnocenecatalyst was 6～8 times lower than that of the analogous zirconocene catalyst, ^(13.C NMR analysis showed that the copolymerobtained using the unsubstituted catalyst Cp_2ZrCl_2 has greater incorporatien of propene than those produced byCH_2CH_2CH=CH_2 substituted Zr and Hf catalysts. The melting point, crystallinity and the viscosity-average molecularweight of the copolymer decreased with an increase of propenc concentration in the feed. Both CH_2CH_2CH= CH_2 substitutedZr and Hf catalysts exhibit little or no difference in the melting point and crystallinity of the produced copolymers. However,there are significant differences between the two zirconocene catalysts. The copolymer produced by Cp_2ZrCl_2 catalyst havemuch lower T_m and X_c than those obtained with the (CpCH_2CH_2CH=CH_2)_2ZrCl_2 catalyst. The density and molecular weightof the copolymer decreased in the order: (CpCH_2CH_2CH=CH_2)_2HfCl_2>(CpCH_2CH_2CH=CH_2)_2ZrCl_2>Cp_2ZrCl_2. The kineticbehavior of copolymerizaton with Hf catalyst was found to be different from that with Zr catalyst.

关键词： Metallocene catalyst Ethylene/propylene copolymerization Methylaluminoxane

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SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2, WANG Yuejun1, FAN Weiming1, LIU Dunyi3. SHI Yuruo3.& MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 510640, china 2. Graduate University of chinese academy of sciences, beijing 10003., china 3. SHRIMP isotope Laboratory, chinese academy of Geological sciences, beijing 10003., china 4. institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of chinese academy of sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-13.) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/23.U ages of 229.4 ± 3.0 Ma and 23..4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/23.U age of 23..0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~23. Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/23.U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

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Application of asymptotic waveform approximation technique to hybrid FE/BI method for 3. scattering

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Science in china(Series F) 2007年第1期50卷 124-134页

作者： PENG Zhen1,2,3.& SHENG XinQing2 1 institute of Electronics, chinese academy of sciences, beijing 100080,{3. 2 Department of Electronic Engineering, beijing institute of Technology, beijing 100081,{3. 3.Graduated University of chinese academy of sciences, beijing 10003.,{3. 1. institute of Electronics Chinese Academy of Sciences Beijing 100080 China 2. Department of Electronic Engineering Beijing Institute of Technology Beijing 100081 China 3. Graduated University of chinese academy of sciences Beijing 100039 China

The asymptotic waveform evaluation （AWE） technique is a rational function approximation method in computational mathemetics, which is used in many appllcations in computational electromagnetlca. In this paper, the performance of the AWE technique in conjunction with hybrid finite element/boundary integral （FE/BI） method is firstly Inveetlgeted. The formuletlon of the AWE applied in hybrid FE/BI method is given in detail. The characteristic implementation of the application of the AWE to the hybrid FE/BI method is discussed. Numarlcel results demonstrate that the AWE technique can greatly speed up the hybrid FE/BI method to acquire wide-band and wide-angle backecatter radar-cross-section （RCS） by complex targets.

关键词： hybrid FE/BI AWE electromagnetic scattering RCS

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Wandering domains in the transcendental dynamics

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chinese Science Bulletin 2001年第1期46卷 34-35页

作者： WANG Yuefeiinstitute of Mathematics, chinese academy of sciences, beijing 100080,{3. institute of Mathematics Chinese Academy of Sciences Beijing China

It is shown that new classes of non-critically finite entire functions do not have wandering domains.

关键词： iteration Fatou set Julia set wandering domains.

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Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan University Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2 , ZHANG Youshui 3. 1. institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, Sichuan, china 2. Graduate University of chinese academy of sciences, beijing 100049, china 3. institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of chinese academy of sciences 100049 Beijing China institute of Geographical sciences Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 259 basic data of 3. debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

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CONSTRUCTION OF A PRECONDITIONER FOR DOMAIN DECOMPOSITION METHODS WITH POLYNOMIAL LAGRANGIAN MULTIPLIERS

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Journal of Computational Mathematics 2001年第2期19卷 213-224页

作者： Qi-ya Hu (institute of Computational Mathematics, academy of Mathematics and Systems sciences,{3., beijing 100080, china) Guo-ping Liang Jin-zhao Liu (institute of Mathematics, academy of Mathematics and Systems sciences, chinese 中科院计算数学与工程计算数学所北京 100080 中科院数学所北京 100080

In this paper we consider domain decomposition methods with polynomial Lagrangian multipliers to two-dimentional elliptic problems, and construct a kind of simple preconditioners for the corresponding interface equation. It will be shown that condition number of the resulting preconditioned interface matrix is almost optimal (namelys it has only logarithmic growth with dimension of the local interface space).

关键词： Domain Decomposition Non-matching grids Lagrangian multipliers Preconditioner Condition number.

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