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The status of Organochlorine Pesticides Pollution in Hubei section of the Yangtze River

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地学前缘 2009年第S1期16卷 81-82页

作者： Chen Liu,Liyuan Guo school of the earth sciences and resources,{3. university of geosciences(beijing),beijing 100083.{3..

The Organochlorine Pesticides(OCPs),such as hexachlorocyclohexane(HCH)and dichlorodiphenyltrichloro ethane(DDT),are well known as typical persistent organic pollutions(POPs).They were worldwide used several decades ago,even today in some *** the water resource is very important in natural environments and essential to agriculture,the pollution of OCPs in water has emerged as worldwide environmental problem. Wuhan section of the Yangtze River is the drinking water source of Wuhan area in Hubei *** addition,Hubei province is an important production base of grain,cotton,oil and *** the rapid development of industry and mass-use of OCPs

关键词： organochlorine pesticides Yangtze River water residues

Propagation characteristics of converted refracted wave and its application in static correction of converted wave

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science china earth sciences 2008年第S2期51卷 226-232页

作者： LIU Yang1,2 & WEI XiuCheng3.1 state Key Laboratory of Petroleum Resource and Prospecting,china university of Petroleum,beijing 102249,china 2 CNPC geophysical Exploration Key Laboratory,china university of Petroleum,beijing 102249,china 3.Exploration and Production Research Institute,sINOPEC,beijing 100083.china china Univ Petr State Key Lab Petr Resource & Prospecting Beijing 102249 Peoples R China china Univ Petr CNPC Geophys Explorat Key Lab Beijing 102249 Peoples R China sINOPEC Explorat & Prod Res Inst Beijing 100083 Peoples R China

Three-component seismic exploration through P-wave source and three-component geophone is an effective technique used in complicated reservoir exploration. In three-component seismic exploration data processing,one of the difficulties is static correction of converted wave. This paper analyzes propagation characteristics of non-converted and converted refracted waves,and discovers a favor-able condition for the formation of converted refracted wave,i.e. the velocity of overlaying medium s wave is much lower than that of underlying medium s wave. In addition,the paper proposes the static correction method of converted wave based on PPs converted refracted wave,and processes the real three-component seismic data with better results of static correction of converted wave.

关键词： PPs converted refracted wave converted wave static correction

Identifying rock blocks based on hierarchical rock-mass structure model

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science china earth sciences 2009年第10期52卷 1612-1623页

作者： XU NengXiong school of Engineering and Technology, china university of {3.sciences, beijing 100083. china school of Engineering and Technology China University of Geosciences Beijing 100083 China

Rock-masses are divided into many closed blocks by deterministic and stochastic discontinuities and engineering interfaces in complex rock-mass engineering. Determining the sizes, shapes, and adjacent relations of blocks is important for stability analysis of fractured rock masses. Here we propose an algorithm for identifying spatial blocks based on a hierarchical 3. Rock-mass structure Model (RsM). First, a model is built composed of deterministic discontinuities, engineering interfaces, and the earth's surface, and the deterministic blocks surrounded by these interfaces are traced. Then, in each deter-ministic block, a network model of stochastic discontinuities is built and the stochastic blocks are traced. Building a unitary wire frame that connects all interfaces seamlessly is the key for our algorithm to identify the above two kinds of blocks. Using this algorithm, geometric models can be built for block theory, discrete element method, and discontinuous deformation analysis.

关键词： rock-mass engineering discontinuity block identification 3. Rock-mass structure Model network model of stochastic discontinuities

Numerical study of the auroral particle transport in the polar upper atmosphere

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science china(Technological sciences) 2008年第10期51卷 1759-1771页

作者： CAI HongTao1,2, MA shuYing1,2 & PU ZuYin3.1 school of Electronic Information, Wuhan university, Wuhan 43.079, china 2 Key Laboratory of {3.space Environment and {3.desy, Ministry of Education of PRC, Wuhan 43.079, china 3.school of earth and space sciences, Peking university, beijing 100871, china 1. school of Electronic Information Wuhan University Wuhan 430079 China 2. Key Laboratory of geospace Environment and geodesy Ministry of Education of PRC Wuhan 430079 China 3. school of earth and space sciences Peking University Beijing 100871 China

starting from the Boltzmann equation and with some reasonable assumptions, a one-dimensional transport equation of charged energetic particles is derived by taking account of major interactions with neutral species in the upper atmosphere, including the processes of elastic scattering, the excitation, the ionization and the secondary electron production. The transport equation is numerically solved, for a simplified atmosphere consisting only of nitrogen molecules (N2), to obtain the variations of incident electron fluxes as a function of altitude, energy and pitch angle. The model results can describe fairly the transport characteristics of pre-cipitating auroral electron spectra in the polar upper atmosphere; meanwhile the N2 ionization rates calculated from the modeled differential flux spectra also exhibit good agreements with existing empirical models in terms of several key parameters. Taking the energy flux spectra of precipitating electrons observed by FAsT satellite flying over EIsCAT site on May 15, 1997 as model inputs, the model-calculated ionization rate profile of neutral atmosphere consists reasonably with that recon-structed from electron density measurements by the radar.

关键词： aurora particle precipitation polar upper atmosphere electron transport equation numerical simulation

TECC Applied in geopark for a Case study of Qixia Planning National geopark

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地学前缘 2009年第S1期16卷 295-296页

作者： Feifei Hu,Mingzhong Tian school of the earth sciences and resources,{3. university of geosciences(beijing),beijing 100083.{3..

This paper applied the theory of TECC(Tourism Environmental Carrying Capacity) into the case of Qixia Planning National *** adopt new planning framework to do the planning of TECC。

关键词： TECC geoheritages basic environment Qixia Planning National geopark

geothermal and fluid flowing simulation of ore-forming antimony deposits in Xikuangshan

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science china earth sciences 2006年第8期49卷 862-871页

作者： YANG Ruiyan1,2, MA Dongsheng2, BAO Zhengyu3. PAN Jiayong2, CAO shuanglin2 & XIA Fei2 1. school of Mathematics and Physics, china university of {3.sciences, Wuhan 43.074, china 2. state Key Laboratory for Research of Mineral Deposits, Nanjing university, Nanjing 210093. china 3. Faculty of earth sciences, china university of {3.sciences, Wuhan 43.074, china 1. school of Mathematics and Physics China University of Geosciences Wuhan 430074 China 2. state Key Laboratory for Research of Mineral Deposits Nanjing University Nanjing 210093 China 3. Faculty of earth sciences China University of Geosciences Wuhan 430074 China

The Xikuangshan Antimony Deposit located in the Mid-Hunan Basin, china, is the larg- est antimony deposit in the world. Based on the hydrogeological and geochemical data collected from four sections, Xikuangshan-Dajienao (AO), Xikuangshan-Dashengshan (BO), Xikuang- shan-Longshan (CO) and Dafengshan (DO) in the Basin, an advanced metallogenic model related to deep-cyclic meteoric water of Xikuangshan Antimony Deposit is put forward in this paper using a model of heat-gravity-driving fluid flow transportation. The simulation results show that the ore-forming fluid of the deposit mainly comes from the Dashengshan and Longshan areas where BO and CO sections are located if the overall basin keeps a constant atmospheric precipitation and infiltration rate during mineralization, and that the average transportation speed of the ore-forming fluids is about 0.2―0.4 m/a.

关键词： ore-forming fluid, numerical simulation, geothermal field, geofluid transport, Xikuangshan, antimony deposits.

Fluid Inclusions and Daughter Minerals of Taibai Gold Deposit, shaanXi Province, china

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Journal of university of science and Technology beijing 2001年第1期8卷 6-9页

作者： YulingXie, Jiuhua Xu, Dayi Qian, Jianping Li resources Engeneering school, university of science and Technology {3., beijing 100083. china Univ sci & Technol beijing Resources Engn Sch Beijing 100083 Peoples R China

A discovery of daughter minerals in fluid inclusions of Taibai gold deposit, shaanxi province has been focused on, which is a unique breccia-cemented gold-bearing system. The breccia zone strikes NWW-sEE, occurring in Devonian strata of southern Qinling Mountains. The cement is mainly composed of ankerite, pyrite, calcite and quartz, which may be divided into four main tectonic-mineralizing stages. Gold mainly occurs in pyrite and ankerite of stage II and IV. It is found that three types of fluid inclusions can be distinguished: (1) aqueous inclusions (type B); (2) CO2-rich inclusions (type C); (3. daughter minerals-containing inclusions (type A). LRM. (Laser Raman Micro-probe) analyses shows that the content of CO2 occupies 54.4%-70.7% (mole fraction, so as the follows) in vapor phases of different type fluid inclusions. CH4 (5.2%-7.3.) and H2s (6.0%-12.7%) exist in both vapor and liquid phases. Many daughter minerals in fluid inclusions of ankerite and quartz have been found. several kinds of daughter minerals, including ankerite, pyrite, arsenopyrite and halite, were determined by using sEM (scanning electron microscope)/EDs (energy dispersive spectrometer) technique. EPMA (electron probe micro-analysis) technique was also applied to study the daughter minerals exposed to the surface of polished thin sections.

关键词： daughter minerals fluid inclusions gold deposit breccia

Interactive graphics mechanical optimum design

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International Journal of Minerals,Metallurgy and Materials 1997年第3期11卷 54-56页

作者： WANG Guobiao (resources Engineering school, university of science and Technology {3., beijing 100083. china)

Virtually all conventional optimizations are Performed in a batch computer environment. No graphic information during the optimization process is provided. The research tactics and implementation procedure of interactivegraphics in mechanical optimum design are presented. An interactive Graphics Mechanical Optimum Design Program(IGMODP) for microcomputers is developed. The example of wheeled loader' s working device optimum design usingIGMODP is carried out.

关键词： interactive graphics mechanical optimum design computer program

Affinities and functional morphology of the Middle Cambrian ornamented tubules from West Hunan,china

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Progress in Natural science:Materials International 2004年第10期14卷 67-71页

作者： ZHU Caifa 1,2 and DONG Xiping 1 (1.school of earth and space sciences,Peking university,{3.100871,china 2.university of Petroleum,{3.102249,china) Peking Univ Sch Earth & Space Sci Beijing 100871 Peoples R China Univ Petr Beijing 102249 Peoples R China

Problematic phosphatic tubular microfossils with ornamented sculptures are documented to exist in limestones of the up-per Middle Cambrian Huaqiao Formation at the Paibi section and the Wangcun section in West Hunan,*** morphological pat-terns,including Ornamented Tube Form I and Ornamented Tube Form II are *** on the analysis of the preservation,wall structure and composition of the fossils,it is deduced that these ornamented tubes may represent carapace spines of some Cambrian arthro-pods with phosphatic carapaces,such as bradoriid *** of functional morphology indicates that the sclerites may rather be considered of a defensive than grasping function on the original organism body.

关键词： Middle Cambrian ornamented tubes affinities functional morphology West Hunan