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The Design and Implementation of Qinghai Province geological Hazards Management Information System

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地学前缘 2009年第S1期16卷 42-43页

作者： Quan Xu~1,Qun Wang~1,Jun Chen~2.Wenqian Jiang~1 1.School of Information Technology,china university of {2.(beijing),beijing 100083,china. 2.Department of Information,china Institute of Geo-Environment Monitoring,beijing 100081,china

The formation and development of geological hazards are extremely complex,depending on factors such as the topography,geology,meteorology, project,human activity,and so on;the geological hazards data include remarkable spatial characteristics and complex attribute *** the amount of geological hazards data is rapidly growing,it has become an urgent demand for geologists to

关键词： geological hazards mapGIS web services ajax

Synthesis of 6-(Bromomethyl)-4-methoxy-5,6,7,8-tetrahydropyrido-[3,2.d]pyrimidin-2.ol from 6-Methylpyrimidine-2.4-diol

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Chemical Research in Chinese Universities 2012年第1期28卷 57-60页

作者： LIU Wei-dong2. DENG Xi-ling2. ZHANG Zhi-li2. WANG Xiao-wei2.and LIU Jun-yi1,2.1. State Key laboratory of Natural and Biomimetic Drug, 2. Department of Chemical Biology, School of Pharmaceutical Sciences, Peking university, {2. 100191, P. R. {2. Peking Univ Sch Pharmaceut Sci State Key Lab Nat & Biomimet Drug Beijing 100191 Peoples R China Peking Univ Sch Pharmaceut Sci Dept Biol Chem Beijing 100191 Peoples R China

6-（Bromomethyl）-4-methoxy-5,6,7,8-tetrahydropyrido[3,2.d]pyrimidin-2.ol（compound 9） was synthe sized from 6-methylpyrimidine-2.4-diol（compound 1） through the crucial steps of 6-methyl alkylating and intramo lecular cyclization. The assignment of the structure of compound 9 was performed by its spectral data, 1H NMR, 13C NMR, HMBC, and HRMS spectra.

关键词： Heterocycle Carbanion Alkylation Reduction Cyclization

Acid/alkali gated photochromism of two diarylperfluorocyclopentenes

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Science china Chemistry 2007年第5期50卷 581-586页

作者： CHEN ZiHui1, ZHAO ShengMin2. LI ZhongYu1, ZHANG Zhi1 & ZHANG FuShi1 1 The Key lab of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua university, {2. 100084, {2. 2.lab of Printing & Packing Materials and Technology-{2. Area Major laboratory, {2. Institute of Graphic Communication, {2. 100084, {2. 1. The Key lab of Organic Optoelectronics & Molecular Engineering of Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 China 2. lab of Printing & Packing Materials and Technology-beijing Area Major laboratory Beijing Institute of Graphic Communication Beijing 100084 China

Two novel diarylfuorocyclopentenes, which underwent gated photochromism, were synthesized. It was found that the photochromic property of these diarylethenes could be switched by alternative addition of acids/alkalis,... 详细信息

关键词： photochromism, diarylethene, gated reactivity, pyridinium betaine

"Three-Component" Digital Prospecting Method: A New Approach for Mineral Resources Quantitative Prediction and Assessment

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Journal of Earth Science 2004年第3期 6-13页

作者： Zhao Pengda Chioa university of geosciences, Wuhan 430074, {2. Chen Jianping School of the Earth Sciences and Resources, {2. university of geosciences, beijing 100083, {2. Chen Jianguo Institute of Mathematical Geology, {2. university of geosciences, Wuhan 430074, {2. Zhang Shouting School of the Earth Sciences and Resources, {2. university of geosciences, beijing 100083, {2. Chen Yongqing {2. geological Survey, beijing 100073, {2.

Three-component" method consists of three close-connected aspects: geological anomaly, diversity of mineralization and mineral deposit spectrum. All these three concepts are not new separately, but it is a new approach to combine these three aspects in one single concept for quantitative mineral resources prediction and assessment and it is also the first time to conduct a more detailed study in each aspect. Investigation and clarification of geological anomalies, diversity of mineralization and spectrum of mineral deposits are realized by digitization and quantification of ore forming controlling factors, ore-existing symbols or marks, characteristics of mineralization and regulation of ore-genesis and laws of distribution. These procedures lead to construction of a "digital model" for mineral resources prediction and assessment.

关键词： three-component" method geological anomaly diversity of mineralization spectrum of mineral deposits.

Positioning localities from spatial assertions based on Voronoi neighboring

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Science china(Technological Sciences) 2010年第S1期53卷 143-149页

作者： GONG YongXi 1,2.3,LI GuiCai 1,LIU Yu 2.& YANG Jian 1 1 Shenzhen Key lab of Recycling Economy,Peking university Shenzhen Graduate School,Shenzhen 518055,{2. 2.nstitute of Remote Sensing and Geographical Information Systems,Peking university,beijing 100871,{2. 3College of Urban and Environmental Science,Peking university,beijing 100871,{2. Peking Univ Shenzhen Grad Sch Shenzhen Key Lab Recycling Econ Shenzhen 518055 Peoples R China Peking Univ Inst Remote Sensing & Geog Informat Syst Beijing 100871 Peoples R China Peking Univ Coll Urban & Environm Sci Beijing 100871 Peoples R China

With the rapid development of Internet,much spatial information contained in non-structured or semi-structured documents is available on the World Wide *** such documents,localities are always textually described using spatial relationships and named places,instead of numerical ***,extracting positional information from locality descriptions is an important *** this paper,we bridge two aspects of locality descriptions,namely generating locality descriptions and positioning localities,and provide a method to compute probability density according to the selection probability of a reference object to describe the position of the target *** operation on uncertainty field is used to deal with locality description involving multiple reference *** metrics are introduced to measure the results of positioning *** choose the mixed selection probability function based on Euclidean distance and Voronoi stolen-area to compute probability density ***,we use three cases to demonstrate the proposed methods.

关键词： geographic information science positioning locality Voronoi neighboring probability density function

Zircon LA-ICPMS study and petrogenesis simulation of Dahuabei pluton in the Wulashan area,Inner Mongolia

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Progress in Natural Science:Materials International 2009年第12期19卷 1727-1737页

作者： Dapeng Li~(a,b),Yuelong Chen~(a,*),Liemeng Chen~c,Zhong Wang~d,Jinbao Liu~d a School of Earth Sciences and Resources,china university of {2.(beijing),beijing 100083,china b State Key laboratory of geological Process and Mineral Resources,china university of {2.,Wuhan 430074,china c State Key laboratory of Ore Deposit Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550002.china d geological Survey Institute of Inner Mongolia,Hohhot 010010,china [a]School of Earth Sciences and Resources China University of Geosciences (Beijing) Beijing 100083 China [b]State Key laboratory of geological Process and Mineral Resources China University of Geosciences Wuhan 430074 China [c]State Key laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China [d]geological Survey Institute of Inner Mongolia Hohhot 010010 China

Dahuabei pluton in the Wulashan area,Inner Mongolia,is an alkaline and peraluminous granitic ***-ICPMS U-Pb dating of zircons indicates that this pluton crystallized at 330±10 *** pluton did not experience apparent zircon *** consistent temperatures between Zr saturation(765℃) and the average zircon-rutile Ti equilibrium(780℃),together with zircon ages and their CL images,indicated that there were no inherited zircons in this *** the simulation of the dry-system crystallization process of magma cooling at 2.0 MPa and 1100-709℃,the phase diagram and composition evolution tendency of different phases were *** magma reached its liquidus at 1069℃.Sanidine was the first crystallized phase;at 709℃the residual magma was less than 4%,and the range of 1069-719℃should be the most suitable approach to the real *** is shown that at least some part of the pluton underwent such isobaric equilibrium crystallization processes during its crystallization.

关键词： Dahuabei pluton Petrogenesis simulation Geochemistry Zircon LA-ICPMS

Impact of Mining Activities upon Environment in Panzhihua Region, Southwestern china

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地球科学进展 2004年第S1期19卷 449-455页

作者： TENGY~1, NIS~2. WANG J~1, ZHANG C~2.XU Z~2.TUO X~2.(1. Institute of Environmental Sciences, beijing Normal university, Belling 100875, {2. 2. Department of Geochemistry, Chengdu university of Technology, Chengdu 610059, {2.)

Mining activities have left huge uncovered slopes, large areas of gangue ground and extensive railings dams. In this paper, we studied some impacts of mining activities upon environment in Panzhihua region, southwestern china. The environmental impacts include ecological destruction, geological disasters, environmental pollution, land damage, solid waste and occupational health effect in study area. The author suggested that local government should take some measure to reduce environmental impact in Pan...

关键词： Mining activity Environmental impact Pollution Panzhihua region SW china

MAJOR SEDIMENTARY CYCLES AND BASIN EVOLUTION OF MESOZOIC IN NORTHERN HIMALAYAS, SOUTH TIBET

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地学前缘 2000年第S1期7卷 41-42页

作者： Shi Xiaoying[WT5,5”BX](china university of {2., beijing 100083,china)

The northern Himalayas was situated on the north margin of the Indian plate and was part of the Gondwana. During Mesozoic and Cenozoic, the geological development of the region was mainly controlled by the evolution of the Neotethyan ocean as well as the movement of the plates (or blocks) on its two sides, showing as a typical passive continental margin [1] . The Mesozoic and Cenozoic sedimentation forms a giant transgression\|regression cycle in this region [2. . The strata have clearly recorded the processes that the Gondwana continent broke up, the Indian plate drifted northward, and consequently collided with the Eurasia, suggesting a Wilson cycle. They also reveals the evolution of the Neotethyan ocean from breakup to expanding, contracting and finally to closing. 1\ The major sedimentary cycles\;The marine Mesozoic and Cenozoic developed continuously in the northern Himalayas, south Tibet, with a total thickness of about 8000m. From the Triassic to Eocene, 70 third\|order sequences have been recognized [2. . Among them 12.are in the Triassic, 2. in the Jurassic, 2. in the Cretaceous and 9 in the Paleogene, with an average duration of 3m.y for each. These can in turn be grouped as 2. sequence sets and 6 mesosequences (2.d order). All of the mesosequences are bounded by prominent discontinuity at bottom, either with subaerial erosion or submarine truncation [2. , suggesting abrupt falls of sea\|level in long\|term changes. The approximate ages for the basal boundaries of these mesosequences are respectively at ca. 2.7Ma (latest Capitanian), 2.5Ma (latest Norian), 177Ma (early Aalenian), 138Ma (mid Tithonian), 103Ma (mid Albian) and 68Ma (late Maastrichtian). Each of mesosequences forms a major sedimentary cycles in the region and may result from the joint effects of global sea\|level changes and regional tectonic\|basin evolution.

关键词： sedimentary cycles basin evolution Mesozoic northern Himalayas Tibet

Sorption behavior of U(VI), ^(2.4)U(VI) and ^(2.8)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in china

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Science china Earth Sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2. LUO Xingzhang3, WANG Ju4, JIN Yuanxin4 & WANG Rucheng1 1. Department of Earth Sciences, State Key laboratory of Mineral Deposit Research, Nanjing university, Nanjing 2.0093, {2. 2. {2. of Materials Analysis, Nanjing university, Nanjing 2.0093, {2. 3. Department of Environmental Science and Engineering, Nanjing university, Nanjing 2.0093, {2. 4. beijing Geology Institute, Nuclear Industry, beijing 10002., {2. Department of Earth Sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China center of Materials Analysis Nanjing university Nanjing {2. Department of Environmental Science and Engineering Nanjing university Nanjing china beijing Geology Institute Nuclear Industry beijing {2.

The first results of sorption experiments of U(VI), 2.4U(VI) and 2.8U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, china are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in china. The present experimental results show that the maximum U(VI) sorption reached 92. at near-neutral pH and the distribution coefficient (Kd) was 12.6 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep {2. disposal repository. No preferential sorption of 2.4U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.