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Isotopic compositions of small shelly fossil Anabarites from Lower Cambrian in Yangtze Platform of South china: Implications for palaeocean temperature

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Progress in Natural Science:Materials International 2007年第10期17卷 1185-1191页

作者： Chen Yongquan1,2, Jiang Shaoyong1, Ling Hongfei1, Yang Jinghong1 and Wan Defan3.1. State Key Laboatory for Mineral Deposits Research and Center for Marine geochemistry Research, Department of Earth sciences, Nanjing University, Nanjing 210093. china 2. Tarim Oilfield Company Exploration & Development Research {3., Ku’erle 841000, china 3. {3. of Mineral Resources, chinese Academy of Geological sciences, Beijing 10003., china) State Key Laboatory for Mineral Deposits Research and Center for Marine geochemistry Research Department of Earth Sciences Nanjing University Nanjing 210093 China arim Oilfield Company Exploration & Development Research institute Ku’erle 841000 China institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

Anabarites belong to small shelly fossils (SSF), which occur widely in the Lower Cambrian strata of Yangtze Platform in South china. They are phosphate shell in composition and represent the earliest stage of the Cambrian bioradiation of Bilateria, the so-called "Cambrian Explosion". In this study, we attempted to separate Anabarites fossils from Lower Cambrian dolostones, and we obtained samples of both the fossils (SSF) and the granular phosphates (GP). Isotopic analyses were performed on samples of SSF, GP, and matrix dolostone (DH-23.. The results showed that the δ3.Si values of the quartz filling in fossils celoms, and the siliceous materials in granular phosphates are -0.6‰ and -0.7‰, which is different from normal sedimentary siliceous rocks from the Lower Cambrian strata (0—0.7‰) as reported by Li et al., but is consistent with the data for siliceous rocks and cherts of submarine hydrothermal origin. It is likely that a later hydrothermal replacement could have taken place in the SSF-bearing sedimentary rocks. The oxygen isotope values of the phosphate of SSF and GP are 16.8‰ and 17.0‰, respectively. These are significantly higher than the Neoproterozoic phosphate ores (10.9‰—13.9‰) as reported by Ling et al., hence, late diagenesis and hydrothermal replacement may not have caused a significant change in the oxygen isotope compositions of the small shelly fossils, and the calculated temperatures (25.4—26.3.) for palaeo-seawater using a SSF phosphate oxygen isotope thermometer are therefore considered here as the upper limit of seawater temperature in the Early Cambrian ocean of the Yangtze Platform.

关键词： Anabarites oxygen isotope silicon isotope paleo-temperature.

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Sequence analysis of mRNA polyadenylation signals of rice genes

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chinese Science Bulletin 2006年第9期51卷 1069-1077页

作者： LU Ying1, 2, GAO Chenxi1,2,3.& HAN Bin1,3.41. National Center for Gene Research, Shanghai institutes for Biological sciences, chinese Academy of sciences, Shanghai 20023., china 2. Graduate School of the chinese Academy of sciences, Beijing 10003., china 3. institute of Plant Physiology and Ecology, Shanghai institutes for Biological sciences, chinese Academy of sciences, Shanghai 20003., china National Center for Gene Research Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200233 China Graduate School of the chinese Academy of sciences Beijing 100039 China institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

The formation of eukaryotic mRNAs involves the cleavage and polyadenylation of pre- mRNAs. To investigate the sequence requirement of putative polyadenylation signals (PASs), poly(A) sites and downstream elements (DUEs) in 3.-end-pro- cessing in rice, we compared expressed sequences tags (ESTs) with poly(A) extremity to full-length cDNA sequences and constructed a database of 12969 pre- mRNA sequences in ?40―+40 nt surrounding the poly(A) sites, which were from 9953.genes. The al- ternative poly(A) sites were revealed in approxi- mately 25% of mRNAs. Nearly 80% of pre-mRNAs showed stringent requirement of the YA (CA or UA) at poly (A) sites for polyadenylation. About 7.9% had the AAUAAA signals on ?40―?1 nt upstream of the poly(A) sites. Over 60% of mRNAs probably used the one- or two-base variants of AAUAAA hexamers as their PASs in 3. fragments. The single-base variants of AAUGAA revealed the high frequency in 11.5% of 3. fragments. The DUEs were detected in 90% of pre- mRNAs, especially more than half of the pre-mRNAs with multi-base variants of AAUAAA had the DUEs surrounding the poly(A) site. The location of DUE is also important for defining the cleavage site. Al- though most of the rice pre-mRNAs did not contain AAUAAA signal, the existence of downstream ele- ments ensured the efficiency of cleavage-polyade-

关键词：多聚腺苷酸序列分析 mRNA 水稻基因工程

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Modeling and verifying Web services driven by requirements:An ontology-based approach

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Science in china(Series F) 2006年第6期49卷 792-820页

作者： HOU Lishan1,3.JIN ZHi1,2 & WU Budan1,4 1. Academy of Mathematics and Systems Science, chinese Academy of sciences, Beijing 100080, china 2. {3. of Computing Technology, chinese Academy of sciences, Beijing 100080, china 3. {3. of Software, chinese Academy of sciences, Beijing 100080, china 4. Graduate University of chinese Academy of sciences, Beijing 100049, china 1. Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China 3. institute of Software Chinese Academy of Sciences Beijing 100080 China 2. institute of Computing Technology Chinese Academy of Sciences Bejing 100080 China 4. Graduate University of chinese Academy of sciences Beijing 100049 China

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.

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Preliminary investigations of platinum-group elements in the Carlin-type gold deposits, southwestern china

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chinese Science Bulletin 1999年第S2期44卷 152-153页

作者： SU Wenchao, QI Liang and HU Ruizhong Open Laboratory of Ore Deposit geochemistry, institute of geochemistry, {3. Academy of sciences, guiyang 550002. china Open Laboratory of Ore Deposit geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

As is well known, platinum-group elements (PGEs) has long been mainly obtained as a byproduct fromsome magmatic deposits of Cu-Ni. The common notion that the platinum-group elements are chemically inert and immobile under most geological conditions. However, a hydrothermal origin at low temperature was recognized for some unusual platinum-group elements occurrences in the unconformity-related uranium deposits in Australia. The possibility of hydrothermal transport of platinum-group elements hasrecently received considerable attention This note introduces the preliminary investigations of platinum-group elements in some Carlin-typegold deposits, southwestern china. 1 Geological

关键词： platinum-group elements Carlin-type gold deposits southwestern china.

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Geological Characteristics of Epithermal Ore Concentrated Areas and Epithermal Ore Deposits in china

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Journal of Earth Science 1999年第1期18卷 47-50页

作者： Li Chaoyang Pan Jiayong institute of geochemistry, chinese Academy of {3., guiyang 550002

The epithermal ore concentrated area is located in Southwestern china. We systematically study the regional geological characteristics such as the basement of Proterozoic, the capping bed, Moho, geothermal feature and tectonics, and discuss the relationship between distributed characteristics of the epithermal ore deposits and ore control factors in this paper. It is concluded that the conditions, under which the epithermal ore deposits form, are huge thick basement of Proterozoic, long time and wide scope developed capping bed and weak magmatic activity. The basement of Proterozoic that enriches volcanic matters and carbon and the carbonaceous bearing and paleo pool bearing capping bed provides main ore source. The large and deep faults and paleopool accordance with gravity anomaly gradient control the distribution of epithermal ore deposits. The lithologic assembles of microclastic rocks and carbonate rocks in the capping bed provide spaces of ore precipitation and create conditions of ore precipitation. The coincidence of many geological factors above forms the epithermal ore concentrated area.

关键词： epithermal ore deposits epithermal ore concentrated areas geological setting Southwestern china.

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Mobility of elements during lamprophyre alteration and altered fluid characteristics in the Zhenyuan gold deposit

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chinese Science Bulletin 1999年第S2期44卷 254-256页

作者： HUANG Zhilong, LlU Congqiang and XlAO Huayun Open Laboratory of Ore Deposit geochemistry, institute of geochemistry, {3. Academy of sciences, guiyang 550002. china Open Laboratory of Ore Deposit geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

LAMPROPHYRES are one of the rock types which are easily subject to alteration. Alteration can not onlychange their texture and mineral assemblage, but also influence their geochemistry properties. The mostavailable data show that alteration will directly influence the content of Au in lamprophyre. For example,in the Superior area of Canada and the Yilgan area of Australia relatively fresh lamprophyres are bothlow in Au contents (3.9×10-9 and 1.7×10-9, respectively), but the contents of Au in altered lamprophyres from both areas are double increased (3.×10-9 and 20×10-9 on average). Lamprophyres arewidely exposed in the Zhenyuan gold deposit, Yunnan Province and they are closely associated with goldmineralization both in space and in time. So the lamprophyres in the Zhenyuan gold deposit can be citedas the most typical example both at home and abroad. Lamprophyres in the mining district have undergonevarying-degree alteration and partly experienced mineralization. On the basis of the mass equilibrium e-

关键词： element mobility altered fluid lamprophyre Zhenyuan gold deposit.

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Holocene grassland vegetation, climate and human impact in central eastern Inner Mongolia

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Science china Earth sciences 2005年第7期48卷 1025-1039页

作者： HUANG Fei1, Kealhofer Lisa2, XIONG Shangfa3.& HUANG Fengbao1 1. Nanjing institute of Geology and Paleontology,chinese Academy of sciences,Nanjing 210008,{3. 2. Anthropology and Sociology Department,Santa Clara University,CA 95053.USA 3. institute of Geology and Geophysics,chinese Academy of sciences,Beijing 100029,{3. Nanjing institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Anthropology and Sociology Department Santa Clara University CA 95053 United States institute of Geology and Geoohysics Chinese Academy of Sciences Beijina 100029 China

Phytolith and pollen preserved in the Taipusi Banner paleosol profile, central eastern Inner Mongolia, provide evidence of Holocene grassland vegetation, climate and human impact. The combined phytolith and pollen records reveal a major change in vegetation composition about 5000 a BP. Before 5000 a BP, the vegetation was dominated by Aneurolepidium chinese-Stipa grandis grassland of C4 grasses. After 5000 a BP, C4 grasses rapidly retreated, indicating a shift to colder and more arid conditions. The gradual invasion of Stipa krylovii, Ag-ropyron desertorum, Ephedra, Chenopodiaceae and Caragana reveal the onset of grassland degeneration. Between 10000 and 8720 a BP, the Aneurolepidium chinese-Stipa grandis grassland included a small proportion of Artemisia shrub and Echionopos type plants, implying a strong winter monsoon and very weak summer monsoon. From 8720 to 7000 a BP, C4 grasses were common, indicating a strengthening of the summer monsoon. Between 7000 and 5000 a BP, the Holocene thermal maximum was evident, with a significant expansion of C4 grasses and the presence of some trees (such as Pinus and Betula, and so on) in or near the study site. From 4200?000 a BP, a sandy grassland of Artemisia and Agropyron desertorum together with Aster-type taxa occurred. Precipitation amelioration took place between 3.00 and 2170 a BP, with a rapid development of Echinops type plants and a small expansion of C4 grasses. From 2170 a BP to present, human activities accelerated the process of grassland degeneration.

关键词： phytolith and pollen records grassland environment change human impact Holocene central eastern Inner Mongolia.

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Atmospheric Deposition-Carried Pb, Zn, and Cd from a Zinc Smelter and Their Effect on Soil Microorganisms

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Pedosphere 2009年第4期19卷 422-433页

作者： YANG Yuan-Gen2, JIN Zhi-Sheng, BI Xiang-Yang, LI Fei-Li, SUN Li, LIU Jie and FU Zhi-You institute of geochemistry, chinese Academy of {3., guiyang 550002.(china) [a]institute of geochemistry Chinese Academy of Sciences Guiyang 550002 (China)

Dust emissions from smelters, as a major contributor to heavy metal contamination in soils, could severely influence soil quality. Downwind surface soils within 1.5 km of a zinc smelter, which was active for 10 years but ceased in 2000, in Magu Town, Cuizhou Province, china were selected to examine Pb, Zn, and Cd concentrations and their fractionation along a distance gradient from a zinc smelter, and to study the possible effects of Pb, Zn, and Cd accumulation on soil microorganisms by comparing with a reference soil located at a downwind distance of 10 km from the zinc smelter. Soils within 1.5 km of the zinc smelter accumulated high levels of heavy metals Zn （508 mg kg^-1）, Pb （95.6 mg kg^-1）, and Cd （5.98 mg kg^-1） with low ratios of Zn/Cd （59.1-115） and Pb/Cd （12.4-23.4）. Composite pollution indices （CPIs） of surface soils （2.52-15.2） were 3.to 13.times higher than the reference soils. In metal accumulated soils, exchangeable plus carbonate-bound fractions accounted for more than 10% of the total Zn, Pb, and Cd. The saturation degree of metals （SDM） in soils within 1.5 km of the smelter （averaging 1.25） was six times higher than that of the reference soils （0.209）. A smaller soil microbial biomass was found more frequently in metal accumulated soils （85.1-43. μg C g^-1） than in reference soils （497 μg C g^-1）, and a negative correlation （P 〈 0.01） of soil microbial biomass carbon to organic carbon ratio （Cmic/Corg） with SDM was observed. Microbial consumption of carbon sources was more rapid in contaminated soils than in reference soils, and a shift in the substrate utilization pattern was apparent and was negatively correlated with SDM （R = -0.773. P 〈 0.01）. Consequently, dust deposited Pb, Zn, and Cd in soils from zinc smelting were readily mobilized, and were detrimental to soil quality mainly in respect of microbial biomass .

关键词： composite pollution index heavy metals microbial biomass saturation degree of metals sequential extrac- tion

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Organic geochemical studies of sinking particulate material in china sea area Ⅱ——Geochemical significance of compositional features of ketone, aldehyde and alcohol compounds

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chinese Science Bulletin 1997年第22期42卷 1894-1898页

作者： DUAN Yi,CUl Mingzhong, MA Lanhua, SONG Jinming, ZHOU Shixin and LUO Binjie1. Lanzhou institute of Geology, chinese Academy of sciences, Lanzhou 73.000, {3. 2. Earthquake Research institute of Lanzhou, SSB, Lanzhou 73.000, {3. 3. institute of Oceanology, chinese Academy of sciences, Qingdao 266071, {3. Lanzhou institute of Geology Chinese Academy of Sciences Lanzhou China Earthquake Research institute of Lanzhou SSB Lanzhou China institute of Oceanology Chinese Academy of Sciences Qingdao China

SINKING particulate organic matter of the sea plays an important role in marine environment. Itnot only provides food for marine organisms and takes part in chemical cycling, but also pro-vides sedimentary organic matter for marine sediments. Therefore, researchers always payclose attention to the source and processes of transport and transformation of marine sinkingparticulate organic matter. Its transport process can be understood by measuring the

关键词： marine sinking paniculate material composition of lipid compounds organic matter source and biochemical pro-cesses.

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Seismic wave propagating in Kelvin-Voigt homogeneous visco-elastic media

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Science china Earth sciences 2006年第2期49卷 147-153页

作者： YUAN Chunfang1, PENG Suping1, ZHANG Zhongjie2 & LIU Zhenkuan3.1. china University of Mining & Technology, Beijing 100083. china 2. institute of Geophysics, {3. Academy of sciences, Beijing 100101, china 3. Exploration and Development Research institute of Daqing Oilfield, Daqing 163.12, china 1. china University of Mining & Technology Beijing 100083 China 2. institute of Geophysics Chinese Academy of Sciences Beijing 100101 China 3. Exploration and Development Research institute of Daqing Oilfield Daqing 163712 China

This paper studies, under a small disturbance, the responses of seismic transient wave in the visco-elastic media and the analytic solution of the corresponding third-order partial differential equation. A plane wave solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differ-ential equation with a pulse source is obtained. By the principle of pulse stacking of particle vibration, the result is extended to the solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differential equation with any source. The velocities of seismic wave propagating and the attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are discussed. The velocities of seismic wave propagating and the coefficient of attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are derived, expressed as functions of density of the media, elastic modulus and visco-elastic coefficient. These results can be applied in inversing lithology parameters in geophysical prospecting.

关键词： Kelvin-Voigt visco-elastic velocity attenuation seismic wave.

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