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Study on lithogeochemistry of Middle Jurassic basalts from southern china represented by the Fankeng basalts from Yongding of Fujian Province

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Science china Earth Sciences 2006年第10期49卷 1020-1031页

作者： ZHOU Jincheng1,2, JIANG Shaoyong1,2, WANG Xiaolei1,2, YANG Jinghong 1,2 & ZHANG Mengqun 3 1. state key Laboratory of mineral deposit {4., nanjing university, nanjing 210093. china 2. Department of Earth Sciences, nanjing university, nanjing 210093. china 3. Modern Analysis Center, nanjing university, nanjing 210093. china 1. state key Laboratory of mineral deposit {4. Nanjing University Nanjing 210093 China 2. Department of Earth Sciences Nanjing University Nanjing 210093 China 3. Modern Analysis Center Nanjing University Nanjing 210093 China

There exists an E-W trending Middle Jurassic volcanic zone in southern china. The Fankeng basalts in the Yongding basin of Fujian Province are considered to be a typical example. The Fankeng basalts have TiO2 contents in the range of 1.92%-3.21%. They are classified as high-Ti basalts. They also have higher total Fe (averaging FeO* = 11.09%). The Middle Jurassic Fankeng basalts from southwestern Fujian have obvious distinctive lithogeochemical features from early Cre- taceous basalts from southeastern coast of china. They have higher HFSE, such as Th, Nb, Ta, Zr and Ti. Their element ratios related with HFSE, such as Zr/Ba, La/Nb, La/Ta ,Zr/Y, Ti/Y, Ba/Nb, K/Ti and Rb/Zr are similar to those of OIB. The most samples have ε Nd(T) of-0.70-0.24. which are near chondrite. Some samples have higher ε Nd(T) of ***, these basaltic magmas might be derived from depleted asthenospheric mantle. The lithogeochemical characteristics of the Fankeng basalts may be caused by interaction between asthenosphere and lithosphere at the time. The (Early-) Middle Jurassic basalts and gabbros from southeastern Hunan, southern Jiangxi and northern Guangdong provinces show similar geochemical features to those of the Fankeng basalts from the Yongding of Fujian. Occurrence of these OIB-type basalts in the area may be regarded as the petrological mark of upwelling of asthenosphere at the time. Upwelling of asthenosphere has led to tectonic extension and the formation of rifted basin in the area.

关键词： interaction between asthenosphere and lithosphere, lithogeochemistry, basalts, Middle Jurassic, southern china.

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The relationship between epithermal and low temperature mineralizations

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Chinese Science Bulletin 1999年第S2期44卷 226-227页

作者： HUA Renmin state key Laboratory of mineral deposit {4., nanjing university, nanjing 210093. china state key Laboratory of mineral deposit {4. Nanjing University Nanjing 210093 China

THE term epithermal as a kind of hydrothermal mineralization was first used by Lindgren in 1933. It describes those ore-forming systems occurring at depths mainly less than 1 km, and at temperatures less than300℃. Epithermal deposits of Cenozoic ages are widely distributed in the Circum-Pacific belt, especiallyin the Southwest Pacific area. From the 1980s on, the study of epithermal ore deposits became an important field of mineral deposit research. Hayba et *** Hedenquist classified the epithermal systemas adularia-sericite or acid-sulphate types, and low sulphidation or high sulphidation types, *** low temperature mineralization, which was exemplified by the deposits in southwest china, refers tothe system at temperature mainly less than 200℃. Besides the distinction in temperature, however, thereexist many differences between epithermal and low temperature mineralizations.

关键词： epithermal mineralization low temperature.

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Carbon and sulfur isotopic compositions of basal Datangpo Formation, northeastern Guizhou, South china:Implications for depositional environment

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Progress in Natural Science:Materials International 2008年第4期18卷 421-429页

作者： Xi Chen, Da Li, Hong-Fei Ling , Shao-Yong Jiang state key Laboratory for mineral deposit {4., Department of Earth Sciences, nanjing university, nanjing 210093. china state key Laboratory for mineral deposit {4. Department of Earth Sciences Nanjing University Nanjing 210093 China

Isotopic compositions of Mn-carbonate and organic carbon from the same individual samples and sulfur isotopic compositions of pyrites in the basal Datangpo Formation were analyzed. Highly 34.-enriched pyrites (d34.pyrite=31.7-59.4.) were precipitated in rel- atively occlusive pore water under anoxic condition in sediments, which is consistent with the observation of large and scattered pyrite framboids. The sulfidic deep ocean was not "oxidized" in the early Datangpo interglacial interval, thus the level of seawater sulfate remained low and marine d34.sulphate remained high. Low d13Ccar (average 7.4.) and abnormal relationship between d13Ccar and frac-tionation (Dcar-org) imply that the negative d13Ccar excursion may have resulted from oxidation of part of a large organic carbon reser-voir. High Dcar-org (average 25.1‰) implicates high CO2 level in the atmosphere. Small standard deviation (1.0‰) of d13Ccar values indicates the Mn-carbonate was precipitated near the water-sediment interface under dysoxic conditions rather than in occlusive pore water in sediments.

关键词： Cisotope S isotope Paleoenvironment Datangpo Mn-carbonate

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Sorption behavior of U(VI), ^(234.U(VI) and ^(238)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 {4., nanjing university, nanjing 210093. china 2. Center of Materials Analysis, nanjing university, nanjing 210093. china 3. Department of Environmental Science and Engineering, nanjing university, nanjing 210093. china 4. Beijing Geology Institute, Nuclear Industry, Beijing 100029, china Department of Earth Sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China Center of Materials Analysis nanjing university nanjing china Department of Environmental Science and Engineering nanjing university nanjing china Beijing Geology Institute Nuclear Industry Beijing china

The first results of sorption experiments of U(VI), 234.(VI) and 238U(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 1226 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 234. 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.

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Potash-rich volcanic rocks and lamprophyres in western Shandong Province:^(4.)Ar-^(39)Ar dating and source tracing

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Chinese Science Bulletin 2002年第2期47卷 91-99页

作者： QIU Jiansheng, XU Xisheng & LO Ching-Huastate key Laboratory of mineral deposit {4. of nanjing university, nanjing 210093. china Department of Earth Sciences, nanjing university, nanjing 210093. china Department of Geology, Taiwan Unive state key Laboratory of mineral deposit {4. of nanjing university Nanjing China Department of Earth Sciences Nanjing University Nanjing China Department of Geology Taiwan University Taibei China

Highly precise 4.Ar-39Ar dating results demon-strate that the ages of potash-rich volcanic rocks in western Shandong Province are 114.7-124.3 Ma, and that of the lamprophyres is 119.6 Ma. The potash-rich volcanic rocks have relatively high (87Sr/86Sr)i ratios ( 0.708715-0.7114.8) and distinctly negative εNd values ( -11.4.--17.54., and are enriched in radiogenic lead (206Pb/204.b=17.34.-17.622, 207Pb/204.b=15.525-15.538, 208Pb/204.b=37.563-37.684.. Similarly, the lamprophyres also have quite low εNd values (-11.57 - -19.64.. Based on the fact that the Sr, Nd and Pb isotopic compositions of potash-rich volcanic rocks are very consistent with that of the clinopyroxene separates, and by integrating comprehensive analyses of their tectonic settings, and extensive comparisons of the Sr, Nd isotopic composi-tions with that of the related simultaneous rocks, it is con-cluded that the potash-rich volcanic rocks and lamprophyres in western Shandong Province were most possibly derived from the partial melting

关键词： potash-rich volcanic rocks lamprophyres 4.Ar-39Ar dating Sr-Nd-Pb isotope tracing western Shandong Province.

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IMPEDANCE CHARACTERISTICS OF POLYFURAN FILMS

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Chinese Journal of Polymer Science 2002年第5期20卷 419-423页

作者： Liang Li Xiao-bo Wan Gi Xue Department of Polymer the state key Laboratory of Coordination Chemistry nanjing university nanjing 210093. china nanjing Univ Dept Polymer State Key Lab Coordinat Chem Nanjing 210093 Peoples R China

Electrochemical impedance spectroscopy (EIS) was first used for the characterization of polyfuran (PFu) films that had been formed electrochemically on an Au electrode. The polyfuran was measured in high oxidation state, intermediate oxidation state and reduction state, respectively. As the oxidation level is increased, the ionic conductivity of PFu/BF4. increases. And impedance studies on PFu show that the anion BF4. appears to be mobile with a high diffusion coefficient of approximately 10(-8) cm(2).s(-1).

关键词： polyfuran electrochemical impedance spectroscopy capacitance

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Mid-low temperature metallogenic province of South china: A continental-scale mineralization and temperature zoning

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Chinese Science Bulletin 1999年第S2期44卷 27-29页

作者： MA Dongsheng state key Laboratory for research of mineral {4.s, nanjing university nanjing 210093. china state key Laboratory for research of mineral {4.s Nanjing University Nanjing 210093 China

CHARACTERIZED by Au,Sb and Hg mineralization, the mid-low temperature metallogenic province in Southchina is composed of the Au-Sb belt in the Proterozoic group on the Jiangnan Old Land, and the Hunan-Guizhou Hg belt in the Cambrian system, the SW china Carlin-type Au belt in the Permian andTriassic, and the Mid-Hunan Sb belt in the Devonian. The latter three are located in the basins respectively on the NW,SW and SE of the Jiangnan Old Land. The province holds nearly 50% Sb ore reserves and supplies about 70% annual antimony mine production in the world, and about 80% both ofexplored reserves and annual output of Hg in china. In the last twenty years, discovery of the micrograined dissemination Au {4.s in the SW china Au belt made an important breakthrough in

关键词： South china continental-scale mineralization ore-forming temperature zoning.

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A sulfur isotope study of fine disseminated gold deposits in the Yunnan-Guizhou-Guangxi triangle area

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Chinese Science Bulletin 1999年第S2期44卷 180-182页

作者： LU jianjun, ZHAI Jianping, CHEN Xiaoming and GAO Jianfeng state key Laboratory of mineral deposit {4., nanjing university, nanjing 210093. china state key Laboratory of mineral deposit {4. Nanjing University Nanjing 210093 China

THE fine disseminated gold deposits in Yunnan-Guizhou-Guangxi triangle area in S. china occur in thesedimentary rocks and are not relative to magmatism in space and genesis. Many authors have studiedthese deposits and obtained different conclusions. This note makes the first systematic study on sulfur isotope compositions to further discuss possible sources of ore-forming materials. 1 Sulfur isotope composition Figure 1 shows variations of sulfur isotope compositions of 232 sulfide separats from various depositsand their host rocks. S S values of pyrite from Mid-Triassic Banna Formation strata in the Jinya ore district can be divided into two groups: -7.4. to -6.4. and 2.7‰ to 14.1‰. Pyrite from the Jinyadeposits has δ34./sup>S values of -7.2‰-1.9‰, stibnite -6.7‰- -4.9‰ and arsenopyrite -4.1‰-

关键词： sulfur isotope fine disseminated gold deposits Yunnan Guizhou Guangxi.

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Regioselective aminohalogenation of β-nitrostyrenes using NCS and NBS as nitrogen/halogen sources

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Science china Chemistry 2010年第1期53卷 140-146页

作者： ZHI SanJun1,2,SUN Hao2,LIN Chen2,ZHANG GuangQian2,LI GuiGen4.& PAN Yi2,3 1 Department of Chemistry,Huaiyin Normal university,Huai’an 221003,china 2 School of Chemistry and Chemical Engineering,nanjing university,nanjing 210093.china 3 state key Lab of Coordination Chemistry,nanjing university,nanjing 210093.china 4.Department of Chemistry and Biochemistry,Texas Tech university,Lubbock,Texas 794.9-1061,USA 1. Department of Chemistry Huaiyin Normal University Huai’an 221003 China2. School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China4. Department of Chemistry and Biochemistry Texas Tech University Lubbock Texas 79409-1061 USA3. State Key Lab of Coordination Chemistry Nanjing University Nanjing 210093 China

Aminohalogenation reaction of β-nitrostyrenes with N-halosuccinimides(N-chloro and N-bromosuccinimides) has been successfully conducted by using nickel acetate as a catalyst in the presence of potassium carbonate and succinimide as *** reaction was easily performed at room temperature under nitrogen gas protection to give dihalorinaed haloamino products in good to excellent yields(60%-98%).The structure has been confirmed by X-ray crystal structure analysis.

关键词： aminohalogenation vicinal haloamines β-nitrostyrenes NBS NCS

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Comparing logic coverage criteria on test case prioritization

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Science china(Information Sciences) 2012年第12期55卷 2826-2840页

作者： FANG ChunRong 1,2,CHEN ZhenYu 1,2 & XU BaoWen 1 1 state key Laboratory for Novel Software Technology,nanjing university,nanjing 210093.china 2 Software Institute,nanjing university,nanjing 210093.china 1. state key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China2. Software Institute Nanjing University Nanjing 210093 China

Logic coverage criteria have been widely used in the testing of safety-critical *** the past few years,fault-based logic coverage criteria have been studied intensively both in theory and in ***,there is a lack of authentic evidence of the comparison of fault-based logic coverage criteria with other logic coverage criteria,such as branch coverage and modified condition/decision coverage(MC/DC).In this paper,we present a comprehensive empirical study that compares these logic coverage criteria on test case prioritization,which is currently a hot topic in software *** useful conclusions are drawn from our research:(1) Fine-grained coverage criteria are always more effective and efficient.(2) The effectiveness of fault-based logic coverage criteria is not significantly different from that of MC/DC in terms of statistics,but the former is more stable.(3) A random strategy is more effective than branch coverage if a certain number of test cases are redundant.

关键词： fault detection capability logic coverage fault-based testing test case prioritization

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