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Study on Sulfide-melt Inclusions in Mantle Xenoliths of Xinchang, Zhejiang

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 5-9页

作者： Jiuhua Xu Xuelei Chu YulingXie Fenglei Bie Dayi Qian university of Science and Technology beijing, beijing {3. China China university of geosciences, beijing {3. China The Research Center of Mineral Resources Exploration, Chinese Academy university of Science and Technology beijing Beijing 100083 China Research Center of Mineral Resources Exploration Chinese Academy of Sciences Beijing 100101 China Institute of Geology Chinese Academy of Sciences Beijing 100029 China China university of geosciences Beijing 100083 China

In minerals of mantle xenoliths captured within Tertiary alkali-basalt from Xinchang, Zhejiang province, China, many sulfidemelt inclusions were found by the observation of polished thin section. Electron microprobe analysis has been applied to detect the components of sulfide-melt inclusions. The result shows that the sulfide phases of inclusions are mainly pentlandite, and secondarily pyrrho- tite, The molar ratio of Ni to Fe, r_Ni,/r_Fe, of mineral phases in sulfide inclusions is related to olivine contents in host mantle xenoliths. The r_Ni/r_Ni, of sulfides from Xinchang samples has a possitive correlation to r_(Fe+Ni),/r_S. The r_(Fe+Ni),/r_S, becomes higher with the increasing of r_Ni/r_Fe In single sulfide-melt inclusions, r_Ni,/r_Fe, r_(Fe+Ni),/r, and Ni contents increase from the center to edge, reflecting a result of different cooling speed in an inclusion. A comparison between the data from Hannuoba, West Eifel of Germany and Nograd-Gomor of east Europe suggests that the composition of the inclusions is different for each area, which indicated that a regional differentiation of sulfide in mantle fluids.

关键词： mantle xenolith sulfide-melt inclusion electron microprobe analysis, Xinchang

Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science China Earth Sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2,3. ZHANG Yili1, BAI Wanqi1, LIU Yanhua4. BAO Weikai5, LIU Linshan1, 2 & ZHENG Du1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, China 2. Graduate School of the Chinese Academy of Sciences, beijing 10003., China 3. College of Resources and Environment, Southwest Agricultural university, Chongqing 4.0716, China 4. The Ministry of Science and Technology, P. C. China, beijing 100862, China 5. Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 61004., China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of Sciences Beijing China College of Resources and Environment Southwest Agricultural University Chongqing China The Ministry of Science and Technology P. C. China Beijing China Chengdu Institute of Biology Chinese Academy of Sciences Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2000 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2000, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.4.0}. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2000, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science China Earth Sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3.1. Faculty of Earth Sciences and Natural Resources, China university of geosciences, beijing {3. China 2. Faculty of Earth Sciences, China university of geosciences, Wuhan 4.0}074. China 3. beijing SHRIMP Center, Institute of Geology, Chinese Academy of Geological Sciences, beijing 10003., China Faculty of Earth Sciences and Natural Resources China University of Geosciences Beijing China Faculty of Earth Sciences China University of Geosciences Wuhan China beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 721 and 773.Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 24.8 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

Discovery of potassic spilite (or poenite) in Langshan Group of Tanyaokou District,Inner Mongolia,China

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Chinese Science Bulletin 1999年第6期44卷 563-567页

作者： PENG RunminDepartment of Geology and Mineral Resources , China university of geosciences, beijing {3. China Department of Geology and Mineral Resources China University of Geosciences Beijing China

It is believed that the albite-potash-feldspar-greenschists in the middle Proterozoic Langshan Group in Tanyaokou District are synsedimentary potassic spilite （or poenite） based on the following facts and features: （ ⅰ ） they occur in beds and look blackish （or apple） green and compact; （ ⅱ ） they bear blasto-glomeroporphyritic and blastocrystalloclastic crystals which consist of （altered） albite laths with hollow skeleton crystal texture in which there are slender dark strips and minor pyroxene, and blasto-amygdaloid filled with pyrite, chlorite, magnetite, etc.; （ ⅲ ） the results of the petrochemical diagrams show that they are orthometamorphites; （ Ⅳ ） Sm-Nd isotopic age of them is 1 824.Ma (model age (tDM) is 2 006—2 13. Ma).

关键词： potassic spilite (or poenite) middle Proterozoic Tanyaokou Deposit Inner Mongolia.

Preparation of Barite/TiO_2 Composite Particle and Interaction Mechanism between TiO_2 and Barite Particles

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稀有金属材料与工程 2011年第S3期40卷 193-197页

作者： Wang Baikun, Ding Hao, Wang Yongkui, Liang Ning China university of geosciences (beijing), beijing {4. China China Univ Geosci beijing Sch Mat Sci & Technol Beijing 100083 Peoples R China

Barite/TiO2 composite particle (B/TCP) was prepared by coating TiO2 on the surfaces of barite particles through mechano-chemical method. The preparation parameters and pigment properties of B/TCP as well as the interaction mechanism between barite and TiO2 were studied. The results indicated that the mechanical co-grinding process and the proportion of TiO2 affected the properties of B/TCP significantly. B/TCP prepared under optimal conditions was similar to TiO2 in pigment properties. It was mainly the strong electrostatic attraction between barite and TiO2 in water that combined them firmly and then formed B/TCP.

关键词： barite/TiO2 composite particle mechano-chemical titanium dioxide interaction mechanism between particles

Mechanisms of invasive population establishment and spread of pinewood nematodes in China

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Science China(Life Sciences) 2009年第6期52卷 587-594页

作者： XIE BingYan1,CHENG XinYue2,SHI Juan3.ZHANG QingWen4.DAI ShuMing1,CHENG Fei Xue2 & LUO YouQing3.1 Institute of Vegetables and Flowers,Chinese Academy of Agricultural Sciences,beijing 100081,China 2 beijing Normal {4.,beijing 100875,China 3.beijing Forestry {4.,beijing 100083.China 4.Chinese Agricultural {4.,beijing 100094.China Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Beijing China beijing Normal university Beijing China beijing Forestry university Beijing China Chinese Agricultural university Beijing China

This paper summarizes the results of our study of the pinewood nematode(Bursaphelenchus xylophi-lus).By population genetic analysis,it was determined that there was no genetic bottle caused by the founder effect and genetic drift in the Chinese invasive *** invasions with large amounts of nematodes from different sources led to rich genetic diversity in the invasive *** high genetic diversity in the invasive process may be one of the genetic mechanisms in its successful *** testing interspecies competition,it was shown that,with high fecundity and a strong competitive ability,*** outcompeted the native species *** in the natural ecosystem during the invasion *** displacement may be one of the ecological mechanisms of ***'s *** addition,an unequal interspecific hybridization with intro-gress was in favor of the invasive species which also accelerated the replacement of *** by *** structures,functions and evolutions of a few important genes that are closely related to the ecological adaptation of pinewood nematodes were studied to explore the molecular mechanism of its ecological ***,the resistance and resilience mechanism of the pine ecosystem invaded by pinewood nematodes was also *** results of these studies uncovered a portion of the genetic and ecological mechanisms of PWN's successful invasion and laid a foundation for further study to obtain a comprehensive interpretation of the mechanisms of the nematode *** results also provided a scientific basis for effectively controlling the occurrence and spread of pine wilt disease which is caused by *** aspects requiring further investigation are considered.

关键词： pinewood nematode bioinvasion genetic diversity ecological adaptation resistance resilience

Paleocontinental Reconstruction:Methodology,Computer Software and an Example of Application

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Journal of Earth Science 1993年第1期12卷 12-18页

作者： Li XiangChina university of geosciences , beijing {3.

Paleocontinental reconstruction is of the nature of multidisciplinary analysis . This paper discusses the significance of some more important disciplines , including paleomagnetism , paleoclimatology and paleobiogeography. Top attention should be paid to the synthetic analysis and geological explanation of geophysical data . Reassembling of the paleocontinents by geometric similarities is preliminary, geological considerations should receive more attention . Several rules constraining the reconstruction are proposed and Eider poles used to reassemble some separated Precambrian median massifs to their mother continents are given . A computer software for paleocontinental reconstruction , GUDALU , is introduced . The software is flexible in that it gives the user maximum freedom to demonstrate his or her geological opinions by providing means of organizing geographic data and rotational parameters ,many kinds of map projection of different features and dynamic editing of the reconstruction maps . Finally, an example of Mesoproterozoic reconstruction is demonstrated .

关键词： paleocontinental reconstruction plate fit . synthetic analysis computer software.

Prediction of Rock Burst with Deep Mining Excavation in Linglong Gold Mine

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Journal of university of Science and Technology beijing 2001年第4期8卷 241-243页

作者： Meifeng Cai, Jinan Wang, Shuanghong Wang Civil and Environmental Engineering School, university of Science and Technology beijing, beijing {3. China Civil and Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China

To predict rock burst in deep mining excavation in Linglong gold mine, systematical laboratory tests of mechanical properties of rock, in situ stress measurement and 3.D FEM analysis on energy distribution in rock mass surrounding deep mining rooms were carried out. According to various prediction criteria of rock burst, it is concluded that rock burst is liable to occur during deep mining excavation in the mine.

关键词： rock burst prediction deep mining excavation Linglong gold mine

Friction Properties of OTS SAMs and Silicon Surface under Water Lubrication

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Journal of Wuhan university of Technology(Materials Science) 2009年第2期24卷 273-277页

作者：王馨 State Key Laboratory of Tribology Tsinghua University Institute of Nuclear and New Energy Technology Tsinghua University

The friction and wear properties of silicon surface covered with octadecyltrichlorosilane （OTS） self-assembled monolayers （SAMs） were investigated by a UMT-2 microtribometer with and without water as lubricant, and then compared with that of bare silicon surface. Dry friction measurement results show that OTS SAMs have a very low friction coefficient compared to bare silicon surface under lower sliding velocity and normal contact load. However, heavy wear occurs on OTS SAMs under higher contact stress and sliding velocity. Under water lubrication, OTS SAMs can prevent wear obviously and meanwhile present low coefficient of friction even under high velocities, The improved frictional and anti-wear property on OTS SAMs surface is attributed to the hydrophobic property of OTS and hydrodynamic effect of water. Furthermore, a wear critical phase diagram for OTS SAMs with and without water was proposed, which indicates that OTS SAMs working under water lubrication owns a wider range of available load and velocity to reduce friction and prevent wear.

关键词： silicon surface OTS SAMs water lubrication friction wear