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Journal of Computational Mathematics 2002年第1期20卷 35-56页

作者： Lan Chieh Huang (ICMSEC, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, China) ICMSEC Academy of Mathematics and System Sciences Chinese Academy of Sciences 北京 100080

Focuses on a study on the fully implicit Crank Nicholson (CN) schemes and three projection methods for approximate preservation of component-consistency under projection. Transformation from incompressible Navier-Stokes equations to differential algebraic equations CN schemes; Local errors of CN projection methods; Numerical boundary conditions.

关键词： differential algebraic equations discrete projection numerical boundary conditions

Rocky Land Desertification and its Driving Forces in the Karst Areas of Rural Guangxi,Southwest China

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Journal of Mountain Science 2008年第4期5卷 350-357页

作者： LIU Yansui WANG Jieyong DENG Xiangzheng Institute of Geographic sciences and Natural Resources Research Chinese Academy of Science Beijing 100101 China Institute of Geographic sciences and Natural Resources Research Chinese Academy of Science Beijing loolo~ ChinaGraduate University of Chinese Academy of Sciences Beijing 100039 China

With a subtropical climate,Guangxi Zhuang Autonomous Region has a typical karst *** desertification has become a serious environmental issue due to its high vulnerability caused by the joint effect of natural settings and human activities,because of which its eco-environment has been deteriorated in recent years,and farmland has been disappearing sharply at the same ***,in turn,has exacerbated the poverty level in the rural areas of the *** this study,we monitored the spatial distribution of rocky land desertification and its temporal evolution using Landsat TM/ETM images of 1985,1995,2000 and *** also analyzed the driving forces of the desertification and its *** constructing regression models by using all the relevant variables and considering the lagged effects as well as fixed effects,we quantified the exact role of different factors causing rocky land desertification in the study area with some new *** new findings in this study are greatly helpful for preserving,restoring and reconstructing the degraded mountain environment in Guangxi and other karst areas in Southwest China,and also for alleviating poverty in the rural areas in the future.

关键词： Rocky land desertification karstmountain area rural poverty driving force Guangxi Southwest China

Floating Population Increase and Its Influence on the Urban Population Situation:A Case Study in beijing

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chinese Journal of Population,Resources and Environment 2005年第1期3卷 27-35页

作者： Wu Peilin 1,2 & Lu Qi 2 1. Shandong University of Technology, Zibo Shandong 255049, China 2. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, China Shandong University of Technology Zibo Shandong 255049 China Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Floating population is a special population group in China resulting from the implementation of household registration system. This paper uses a set of floating population survey data, population censuses data and statistical data to analyze the increase and influence of floating population on the urban population situations in beijing. It is found that beijing has experienced a rapid increase of floating population since the 1990s and that the increase of this group has become the key factor of the current population expansion in the city. Its distribution in the urban regions intensified and extended the suburbanization process of the capital. In addition, the population structures of sex, age, education and employment in beijing have changed to some extent due to the influx of floating population.

关键词： Floating population Household registration system (Hukou) Population expansion Suburbanization Population structure beijing

SYNTHESIS　AND　STRUCTURAL　CHARACTERIZATION　OF　TRIPYRRANE-CONAINING　BISMACROCYCLE

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chinese Chemical Letters 1996年第5期7卷 397-398页

作者： Shi Ming DONG Duo Yuan WANG (Institute of Photographic Chemistry, chinese academy of sciences. beijing 100101) Institute of Photographic Chemistry Chinese Academy of Sciences Beijing 100101

Abstract: A novel tripyrrane-containing bismacrocycle ligand was acquired by the improved procedure of the metal template 1:1 Schiffbase condensation. The condensation of diformyltripyrrane With 3.4,3'.4'-tetraamino-... 详细信息

关键词： TEXAPHYRIN PORPHYRIN

Background contents of heavy metals in sediments of the Yangtze River system and their calculation methods

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Journal of Environmental sciences 1995年第4期7卷 422-429页

作者： Zhang Chaosheng, Zhang Shen, Zhang Licheng, Wang Lijun(Institute of Geography , chinese academy of sciences , beijing 100101 , China) Inst of Geography Chinese Academy of Sci Beijing China China

ＢａｃｋｇｒｏｕｎｄｃｏｎｔｅｎｔｓｏｆｈｅａｖｙｍｅｔａｌｓｉｎｓｅｄｉｍｅｎｔｓｏｆｔｈｅＹａｎｇｔｚｅＲｉｖｅｒｓｙｓｔｅｍａｎｄｔｈｅｉｒｃａｌｃｕｌａｔｉｏｎｍｅｔｈｏｄｓＺｈａｎｇＣｈａｏｓｈｅｎｇ，Ｚｈ... 详细信息

ＢａｃｋｇｒｏｕｎｄｃｏｎｔｅｎｔｓｏｆｈｅａｖｙｍｅｔａｌｓｉｎｓｅｄｉｍｅｎｔｓｏｆｔｈｅＹａｎｇｔｚｅＲｉｖｅｒｓｙｓｔｅｍａｎｄｔｈｅｉｒｃａｌｃｕｌａｔｉｏｎｍｅｔｈｏｄｓＺｈａｎｇＣｈａｏｓｈｅｎｇ，ＺｈａｎｇＳｈｅｎ，ＺｈａｎｇＬｉｃｈ...

关键词： Yangtze River sediments heavy metalsi robust statistics data transformation.

Detection of the urban heat island in beijing using HJ-1B satellite imagery

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Science China Earth sciences 2010年第S1期53卷 67-73页

作者： YANG Jun1,GONG Peng2,ZHOU JinXing3,HUANG HuaBing2 & WANG Lei2 1 Key Laboratory of Silviculture and Conservation,Ministry of Education,beijing Forestry University,beijing 100083,China 2 State Key Laboratory of Remote Sensing Science,jointly sponsored by the Institute of Remote Sensing Applications,chinese academy of sciences and beijing Normal University,beijing 100101,China 3 Institute of Desertification Studies,chinese academy of Forestry,beijing 100091 China Key Laboratory of Silviculture and Conservation Ministry of Education Beijing Forestry University Beijing China State Key Laboratory of Remote Sensing Science jointly sponsored by the Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Beijing China Institute of Desertification Studies Chinese Academy of Forestry Beijing China

Satellite images are used extensively in studying the urban heat island(UHI) *** evaluated the suitability of thermal infrared(TIR) data from the HJ-1B satellite for detecting UHI using a case study in *** modified algorithms for retrieving the land surface temperature(LST) from HJ-1B data were *** results were compared with LST images derived from a Landsat TM thermal band and the MODIS LST *** spatial pattern of UHI generated using HJ-1B data matched well with that produced using TM and MODIS *** the two algorithms,the mono-window algorithm performed better but further tests are *** more frequent coverage than TM and higher spatial resolution than MODIS,the HJ-1B TIR data present a unique opportunity to study thermal environments in cities in China and neighboring countries.

关键词： surface temperature NDVI mono-window algorithm single-channel algorithm

Trophic transfer of mercury and methylmercury in an aquatic ecosystem impacted by municipal sewage effluents in beijing, China

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Journal of Environmental sciences 2010年第8期22卷 1189-1194页

作者： Jianjie Fu, Yawei Wang, Qunfang Zhou, Guibin Jiang State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, China. State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Gaobeidian Lake, located in beijing, China, serves as a recipient lake for efluents from a large municipal sewage treatment plant （MSTP）. In order to evaluate the effects of discharging MSTP efluent on the mercury contamination of the local aquatic ecosystem, sediment cores, water, plankton, fish, and turtle samples were collected from Gaobeidian Lake for mercury speciation analysis. High concentrations of total mercury （T-Hg） were detected in sediment cores （5.24–17.0 μg/g dry weight （dw）, average： 10.1 μg/g）. The ratio of methylmercury （MeHg） to T-Hg was less than 0.3% in sediments and ranged from 35% to 76% in biota samples. The highest level of T-Hg and MeHg were found in aquatic bryophyte and crucian carp （3673 and 437 ng/g dw, respectively）. The relative contents of MeHg were significantly correlated with trophic levels （R2 = 0.5506, p 0.001）, which confirmed that MeHg can be bio-transferred and biomagnified via food chain in this aquatic ecosystem.

关键词： methylmercury total mercury trophic levels aquatic ecosystem municipal sewage treatment plants

Investigation of a New Exsolved Cu-Fe-S Phase in“Abnormal Sphalerite”

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Acta Geologica Sinica(English Edition) 1991年第1期65卷 27-36,110-111页

作者： Li Jiuling Wang Su Institute of Mineral Deposits, chinese academy of Geolgical sciences,beijing beijing Laboratory of Electron Microscopy, chinese academy of sciences, beijing Institute of Mineral Deposits Chinese Academy of Geolgical Sciences Beijing China

A new exsolved copper-iron-sulfur phase in sphalerite has been found in the Dajing cassiterite- sulfidecopper-silver-tin deposit, Inner Mongolia, China. After investigating the optical properties, chemical composi-tion, crystal structure and exsolved Characters of the exsolved phase, the authors present important evidencefor its being a new exsolved copper-iron-sulfur phase mineral. Its formation mechenism is discussed in consider-ing heating experiments, phase equilibrium data and the geology of the deposit.

关键词： Ph Fe Abnormal Sphalerite Cu

The further crystallographic refinement of trichosanthin at 2.7A resolution and the comparison among the three molecular structures in two crystal forms

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chinese Journal of Chemistry 1994年第3期12卷 223-230页

作者： ZHANG, Lei XIA, Zong-Xiang Shanghai Institute of Organic Chemistry, chinese academy of sciences, Shanghai 200032, ChinaWU, Shen DONG, Yi-ChengInstitute of biophysics, chinese academy of sciences, beijing 100101, China Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China Institute of biophysics Chinese Academy of Sciences Beijing 100101 China

The three-dimensional structure of trichosanthin at 2.7A resolution has been improved further, by refitting one of the C-terminal tails, adjusting 16 residues in the molecular surface regions, discarding some water molecules with high B values, and adjusting weights during the further refinement. The R-factor has been reduced to 18.5% and the r.m.s deviations from ideal geometry are also improved. The structures of the two molecules in the monoclinic asymmetric unit and the only molecule in the orthorhombic asymmetric unit are compared with one another. The main-chain structures for most of the residues in the three molecules are substantially the same. However, the courses of the three C-terminal tails are completely different, and the intermolecular interactions resulting from the particular packing of the molecules in the crystals account for the differences. The strand Be-2 and the preceding B-turn in small domain show large r.m.s. deviations among the three molecules and they are also involved in intermolecular interactions.

关键词： Trichosanthin ribosome-inactivating protein C-terminal tail crystallographic refinement structural comparison.

THE DUAL MIXED METHOD FOR AN UNILATERAL PROBLEM

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Journal of Computational Mathematics 2003年第6期21卷 733-746页

作者： Lie-heng Wang(LSEC, ICMSEC, academy of Mathematics and System sciences, chinese academy of sciences,beijing 100080, China) 中科院数学与系统科学院 LSEC ICMSEC CAS 北京 100080

In this paper, the dual mixed method for an unilateral problem, which is the simplified modelling of scalar function for the friction-free contact problem, is considered. The dual mixed problem is introduced, the existence and uniqeness of the solution of the problem are presented, and error bounds O(h3/4) and O(h3/2) are obtained for the dual mixed finite element approximations of Raviart-Thomas elements for k = 0 and k = 1 respectively.

关键词： Dual Mixed Method Unilateral Problem.