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Nitrogen isotopic geochemical characteristics of crude oils in several basins of china

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science china earth sciences 2005年第8期48卷 1211-1219页

作者： CHEN Chuanping1,2, MEI Bowen1 & CAO Yacheng3.1. Jianghan Petroleum university, Jingzhou 43.100, china 2. Huazhong university of {3. and Technology, Wuhan 43.047, china 3. nanjing Institute of Soil {3., Chinese Academy of {3.s, nanjing 210008, china 1. Jianghan Petroleum university 434100 Jingzhou China 2. Huazhong university of science and Technology 430047 Wuhan China 3. nanjing Institute of Soil science Chinese Academy of Sciences 210008 Nanjing China

Nitrogen isotopic ratios of crude oils with different physical and chemical properties in several basins of china have been measured and their geochemistry has been studied ele-mentally combined with molecular organic geochemistry methods. The data indicate that δ 15N is in the range of ?6‰-20‰. They vary with the oils in different sedimentary types of basins. The oils forming in the limnic environment have lower δ 15N with the value of about 1‰-5‰ whereas the oils in saline or semi-saline environment have higher δ 15N, with most samples being above 10‰ and some exceeding 17‰. The average nitrogen isotopic ratio of oils from the Ordovician formation in the Tarim Basin is the lowest, with most samples having δ 15N below zero, which reflects possibly the characteristic of the oils originating mainly from the organic matter formed in marine carbonate sedimentary environment. The δ 15N distribution can be altered by fractionation. It increases obviously because of biodegradation and decreases during hydrocarbon migration. However, the effect of nitrogen isotopic fractionation in the short distance migration is uncon-spicuous.

关键词： nitrogen isotope, crude oil, sedimentary environment, isotopic fractionation, china.

Statistic Characteristics of Logistic Iteration and its Application inGenerating Even Distributed Random Numbers

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Communications in Nonlinear science and Numerical Simulation 1998年第2期3卷 3-5页

作者： Nailong GUO (department of Aerodynamics, nanjing university of Aeronautics and Astronautics, nanjing 210016,{3.) department of Aerodynamics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

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关键词： Logistic iteration even distributed random numbers statistic characteristics

Bathynotus:A key trilobite taxon for global stratigraphic boundary correlation between Cambrian Series 2 and Cambrian Series 3

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Progress in Natural science:Materials International 2009年第1期19卷 99-105页

作者： Jin Peng a,b,Yuanlong Zhao b,Jinliang Yuan c,Lu Yao b,Hong Yang b a department of earth sciences,{3. university,{3. 210093,china b College of Resource and Environmental Engineering,Guizhou university(Caijiaguan Campus),Guiyang 550003.china c {3. Institute of Geology and Palaeontology,Chinese Academy of sciences,{3. 210008,china [a]department of earth sciences Nanjing University Nanjing 210093 China [b]College of Resource and Environmental Engineering Guizhou University (Caijiaguan Campus) Guiyang 550003 China [c]Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Cambrian trilobite Bathynotus is a special morphology of Redlichiid,which is characterized by a wider thorax axis and an 11th macropleural segment bearing a long,backwardly directed ***,its 12th and 13.h pleural segments are narrow and they terminate at a fulcrum where they fuse together and to the posterior edge of the long macropleural *** genus is widely distributed,occurring in North America,Siberia,the Altay-Sayan fold belt of Russia,South china,the Tarim Basin of china,and *** occurs primarily in deposits of the upper part of the continental slope,at the transition between stable platform settings and subsiding margins of the late Early ***,we recognize three species of Bathynotus from china,including *** which is widespread around the *** six species of Bathynotus have been reported from Siberia and the Altay-Sayan fold belt area of Russia,data presented here suggest that only three of these species are *** exhibits a short geological range,with its first occurrence late in the unnamed Cambrian Series 2 and the last appearance datum of Bathynotus at the boundary of Cambrian Series 2 and Cambrian Series *** late appearance datum(LAD) of Bathynotus provides an important global stratigraphic marker of the boundary between Cambrian Series 2 and Cambrian Series 3.

关键词： Bathynotus Age Cambrian Series 2 Boundary Correlation

Zircon SHRIMP U-Pb geochronology and petrogenesis of the plagiogranites from the Lagkor Lake ophiolite,Gerze,Tibet,china

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Chinese science Bulletin 2007年第5期52卷 651-659页

作者： ZHANG YuXiu1,2, ZHANG KaiJun1,3. LI Bing1,2, WANG Yang1,2, WEI QingGuo1,2 & TANG XianChun1,2 1 Key Laboratory of Marginal Sea Geology, Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 510640, china 2 Graduate university, Chinese Academy of sciences, Beijing 10003., china 3.department of earth sciences, nanjing university, nanjing 210093, china Key Laboratory of Marginal Sea Geology Guangzhou Institute of GeochemistryChinese Academy of Sciences Guangzhou 510640 China

地关系与 petrographical 一起， petrological ，和 geochemicalcharacteristics ，和锆石人口，显示从在 Bangong-Nujiang 缝术地区的 Lagkor Lakeophiolite 的 plagiogranites (～ Gerze 县的 20 km 南方，中央西藏，中国)，由在海洋的外壳的运输期间的可锻的砍源于含水的斑粝岩的 anatexis 。因此，这种 plagiogranite 比传播海洋的外壳晚对或很少同时代。锆石虾 166 ±使 2.5 妈变老因为 plagiogranites 显示海洋的盆在中间的侏罗记在 Bangong-Nujiang 地区的西方的部分存在。

关键词：西藏改则县拉果错湖泊蛇绿岩斜长花岗岩锆SHRIMP U-Pb地质年代岩石成因

LOW POTENTIAL ELECTROPOLYMERIZATION OF ANISOTROPIC CONDUCTIVE POLYTHIOPHENE FILMS AND FABRICATION OF ELECTRICAL DEVICES

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Chinese Journal of Polymer science 1999年第2期17卷 99-111页

作者： Xiao-bo Wan Yun Lu Xiao-rong Liu Liang Zhou Shi Jin Gi Xue department of Polymer science and Engineering, the State Key Laboratory of Coordination Chemistry, nanjing university,{3., china nanjing Univ Dept Polymer Sci & Engn State Key Lab Coordinat Chem Nanjing 210093 Peoples R China

The Complexation of thiophene with a Lewis acid with moderate acidity as a solvent, such as BF3.ethyl ether (BFEE) remarkedly lowered the electrochemical polymerization potential. The positively charged metal surface of electrode in the process of electrochemical deposition enhanced the coordination interaction between pi-electrons of thiophene unit and the metal, which makes thiophene rings lie parallel to the surface of electrode, resulting in a highly ordered polymeric structure. Because of the large intra-chain transfer integrals, the transport of charge is believed to be principally along the conjugated chains, which is much greater than the inter-chain hopping. The specific electrical resistance across the polythiophene film thickness is more than 10(4) times than that along the surface plane of the film. In this paper we review the recent development of polymerization technique by low potential electrochemical method performed in our lab and several electrical devices in which the compact polythiophene films, such as anionic and cationic sieves, and laminate film junction of undoped polythiophene derivatives were used.

关键词： conductive polymer polythiophene anisotropy electric device film junction

SOCIAL POLARIZATION AND SEGREGATION IN BEIJING

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Chinese Geographical science 2001年第1期11卷 17-26页

作者： GU Chao-lin (department of Urban and Resource sciences, nanjing university,{3., P. R. china) department of Urban and Resource sciences Nanjing University Nanjing P. R. China

The biggest change in Beijing during the last decade has been in its social structure. This transition is changing the existing situation of social "equality", and leads to polarization both in individual communities and in society as a whole. As a result, social variations and conflicting interest are growing, and some new social groups are emerging. In this paper we seek to exPlore a new urban Phenomenon in post-1984 Beijing: social polarization and segregation. At first, we will discuss *** explaining social polarization. The elements and the processes can be traced back to two main aspects of the economic reforms, namely the internal reforms unleashing a huge rural exodus and the open door policy. Special attention will be paid to the new lower end of the social ladder, which is made up largely by rural migrantsthat make up the so-called floating population. Finally we will explore how these social changes translate into urban segregation, with some consideration for future developments.

关键词： social polarization urban segregation Beijing

A Feedback-Based Web Search Engine

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Wuhan university Journal of Natural sciences 2004年第5期9卷 561-568页

作者： ZHANG Wei-feng 1,2,3., XU Bao-wen 2,3.4 , ZHOU Xiao-yu 2,3.4 1. department of Computer science and Engineering, nanjing university of Posts and Telecommunications, {3. 210003. Jiangsu, china 2. department of Computer science and Engineering, Southeast university, {3. 210096, Jiangsu, china 3. Jiangsu Institute of Software Quality, {3. 210096 Jiangsu, china 4. The State Key Laboratory of Software Engineering, Wuhan university, Wuhan 43.072, Hubei, china department of Computer science and Engineering Nanjing University of Posts and Telecommunications . Nanjing 210003 Jiangsu China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. Since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. Key words WWW - search engine - query reconstruction - feedback CLC number TP 3.1. 13..4 Foundation item: Supported by the National Natural science Fundation of china (603.3.66). National Grand Fundamental Research 973.Program of china (2002CB3.200). Opening Foundation of State Key Laboratory of Software Engineering in Wuhan {3., Opening Foundation of Jiangsu Key Laboratory of Computer Information Processing Technology in Soochow {3.Biography: ZHANG Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback

Magnetic mineralogy of the Hongqiling Cu-Ni sulphide deposit: Implications for ore genesis

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Progress in Natural science:Materials International 2007年第10期17卷 1192-1198页

作者： Xi Aihua1,2, Ge Yuhui1, Cai Yuanfeng2 and Zhang Xuefeng3.1. Faculty of Resources & Environment, Southwest Petroleum university, Chengdu 610500, china 2. State Key Laboratory for Endogenic Metal Deposit Research, nanjing university,{3., china 3. department of Natural Resources & Technology Information, china university of Petroleum, Beijing 102249, china) Faculty of Resources & Environment Southwest Petroleum University Chengdu 610500 China State Key Laboratory for Endogenic Metal Deposit Research Nanjing University Nanjing 210093 China department of Natural Resources & Technology Information China University of Petroleum Beijing 102249 China

Pyrrhotite is one of the common ore minerals in Cu-Ni sulphide deposits, but only monoclinic pyrrhotite is ferromagnetic at room temperature. X-ray and EPA analyses reveal that most pyrrhotite forming sideronitic texture in the Hongqiling Cu-Ni sulphide deposit is monoclinic, but that in the massive ore is a mixture of monoclinic and hexagonal pyrrhotites. Differential thermal and magnetic- thermogravimetric analyses of massive ore indicate a magnetic transition and heat absorption at 3.3., suggesting that this temperature is the thermomagnetic and phase transition point of pyrrhotite. For massive pyrrhotite ores heated at 400oC for 3. h and then quenched by cool water, the monoclinic pyrrhotite (mpo) transforms completely into the hexagonal pyrrhotite (hpo). However, all the pyrrhotites resulting from slow cooling of the sample in air are mpo. These results indicate that transformation between hpo and mpo depends upon the cooling rate. Therefore, massive ores in this deposit might have been formed via rapid cooling of ore melts. On the other hand, it is significant to study the effect of the ratio of the magnetite in total ores on the genesis of magmatic Cu-Ni suphide deposits.

关键词： pyrrhotite magnetite genesis of Cu-Ni sulphide deposit Hongqiling.

The Lifespan for 3.D Spherically Symmetric Compressible Euler Equations

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Acta Mathematica Sinica,English Series 1998年第4期14卷 527-534页

作者： Yin Huicheng Qiu Qingjiu, department of Mathematics, nanjing university, nanjing 210093,{3. department of Mathematics Nanjing University

In this paper, we study the lifespan of solutions for three dimensional compressible Euler equations with spherically symmetric initial data that is a small perturbation of amplitude ε from a constant state. From our... 详细信息

关键词： Lifespan Compressible Euler equation