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Sr-Nd isotopic compositions of the Changjiang sediments: Implications for tracing sediment sources

Science china Earth Sciences 2007年第10期50卷 1556-1565页

作者： YANG ShouYe1?, JIANG ShaoYong2, LING HongFei2, XIA XiaoPing3, SUN Min3 & WANG DeJie4 1 state key laboratory of Marine Geology, Tongji university, Shanghai 200092, china 2 state key laboratory for mineral deposit research, nanjing university, nanjing 210093, china 3 Departmen of Earth Sciences, The university of Hong Kong, Hong Kong SAR, china 4 Development research Center, china Geological Survey, Beijing 100083, china 1. state key laboratory of Marine Geology Tongji University Shanghai 200092 China 2. state key laboratory for mineral deposit research Nanjing University Nanjing 210093 China 3. Department of Earth Sciences The University of Hong Kong Hong Kong SAR China 4. Development research Center China Geological Survey Beijing 100083 China

The suspended particulate and fine-grained floodplain sediments were collected from the main stream and tributaries of the Changjiang River for Sr-Nd isotopic measurements. The εNd(0) values gradually decrease downstream from -10.8 on average in the upper reaches to -12.3 in the lower reaches, whereas the 87Sr/86Sr ratios increase correspondingly, averaging 0.721899 and 0.725826 respectively in the upper and middle-lower reaches. The compositional variations primarily reflect the complex con- trols of provenance rocks, chemical weathering, and sediment characters between different catchments, among which the abnormal Sr-Nd isotopic compositions of the Yalong, Fujiang, Tuojiang and Yuanjiang rivers indicate the sediment provenance contributions from the Emeishan Basalt in the upper reaches and the old metamorphic and siliceous rocks in the middle-lower reaches. The Sr-Nd isotopic ratios of the Changjiang sediments can better reflect the average composition of weathered continental crust compared to other major rivers in the world because of the unique source rock types in the Changjiang drainage basin. The recognition of the Sr-Nd isotopic systematics of the Changjiang sediments will contribute to our understanding of the Changjiang evolution history and continental weathering processes during the Cenozoic, and also to reconstructing the paleoenvironmental changes in East china and the marginal seas.

关键词： Sr-Nd isotopes, sediment, Changjiang River, source rock, provenance

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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 research, nanjing university, nanjing 210093, china state key laboratory of mineral deposit research 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 research, Department of Earth Sciences, nanjing university, nanjing 210093, china state key laboratory for mineral deposit research 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 34S-enriched pyrites (d34Spyrite=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 d34Ssulphate 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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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 research, 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 research 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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Potash-rich volcanic rocks and lamprophyres in western Shandong Province:^(40)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 research 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 research of nanjing university Nanjing China Department of Earth Sciences Nanjing University Nanjing China Department of Geology Taiwan University Taibei China

Highly precise 40Ar-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 ( 0.708715-0.711418) and distinctly negative εNd values ( -11.47--17.54), and are enriched in radiogenic lead (206Pb/204Pb=17.341-17.622, 207Pb/204Pb=15.525-15.538, 208Pb/204Pb=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 40Ar-39Ar dating Sr-Nd-Pb isotope tracing western Shandong Province.

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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 deposits, nanjing university nanjing 210093, china state key laboratory for research of mineral deposits 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 deposits 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 research, nanjing university, nanjing 210093, china state key laboratory of mineral deposit research 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 δ34S 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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Sensitive biosensing strategy based on functional nanomaterials

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Science china Chemistry 2011年第8期54卷 1202-1217页

作者： JU HuangXian state key laboratory of Analytical Chemistry for Life Science Department of Chemistry, nanjing university, nanjing 210093, china 1. state key laboratory of Analytical Chemistry for Life Science Department of Chemistry Nanjing University Nanjing 210093 China

The first decade of the 21st century has been labeled as "the sensing decade". The functional nanomaterials offer excellent platforms for fabrication of sensitive biosensing devices, including optical and electronic biosensors. A lot of works have fo- cused on the biofunctionalization of different nanomaterials, such as metal nanoparticles, semiconductor nanoparticles and carbon nanostructures, by physical adsorption, electrostatic binding, specific recognition or covalent coupling. These biofunc- tionalized nanomaterials can be used as catalysts, electronic conductors, optical emitters, carriers or tracers to obtain the ampli- fied detection signal and the stabilized recognition probes or biosensing interface. The designed signal amplification strategies have greatly promoted the development of stable, specific, selective and sensitive biosensors in different fields. This review in- troduces some novel principles and detection strategies in the area of biosensing, based on functional nanomaterials. The gen- eral methods for biofunctionalization of nanomaterials with biomolecules and their biosensing application in immunoassay of protein, DNA detection, carbohydrate analysis and cytosensing are also described.

关键词： nanobiosensing biosensors nanomaterials biofunctionalization signal amplification bioanalysis biological recognition

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Expression of Recombinant Chinese Bovine Enterokinase Catalytic Subunit in P. pastoris and Its Purification and Characterization

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Acta Biochimica et Biophysica Sinica 2004年第7期36卷 513-517页

作者： Lei FANG, Qi-Ming SUN, and Zi-Chun HUA*The state key laboratory of Pharmaceutical Biotechnology, nanjing university, nanjing 210093, china The state key laboratory of Pharmaceutical Biotechnology Nanjing University Nanjing 210093 China

Enterokinase is a tool protease widely utilized in the cleavage of recombinant fusion proteins. cDNA encoding the catalytic subunit of Chinese bovine enterokinase (EKL) was amplified by PCR and then fused to the 3′ end of prepro secretion signal peptide gene of α-mating factor from Saccharomyces cerevisiae to get the α-MF signal-EKL-His6 encoding gene by PCR. Then the whole coding sequence was cloned into the integrative plasmid pAO815 under the control of a methanol-inducible promoter and transformed GS115 methylotrophic strain of Pichia pastoris. Secreted expression of recombinant EKL-His6 was attained by methanol induction and its molecular weight is 43 kD. Because of the existence of His6-tag, EKL-His6 was easily purified from P. pastoris fermentation supernatant by using Ni2+ affinity chromatography and the yield is 5.4 mg per liter of fermentation culture. This purified EKL-His6 demonstrates excellent cleavage activity towards fusion protein containing EK cleavage site.

关键词： recombinant enterokinase secreted expression Ni2+ affinity chromatography fusion protein cleavage

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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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