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chinese Science Bulletin 2000年第S1期45卷 26-34页

作者： WANG Yunpengguangzhou institute of geochemistry, chinese {4. of sciences, guangzhou 51064., china guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou China

This paper presents the contents of 17 kinds of trace elements in plant leaf samples collected from 4.sections in the North Jiangsu oil field, and the dada on their visible-near infrared spectra. By comparing the results of the inner and outer oil-gas remote-sensing anomaly areas, the plant trace element composition, and the enrichment characteristics and their influence on the plant spectral properties are described. The results indicated that the plant leaves had very strong enrichment ability toward some elements such as Mg, Ca, K, Na, Fe, Al, Mn, V, Zn and Cr. The plant leaves from the oil-gas abnormal areas were enriched in trace elements of the Fe-series, but depleted in alkali and alkali-earth metal elements. The plant trace elements had a strong influence on the 'blue-shift' strength and the reflectance of visible bands. And the ratios between Fe, Co and K, Na, Cd, Cu, Ba are the effective remote-sensing oil-indicating factors of plant trace elements. plant trace element, geochemistry, remote

关键词： plant trace element geochemistry remote sensing spectra North Jiangsu oil fleld.

Trace element characteristics and origin of intergranular components in mantle peridotites

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chinese Science Bulletin 2000年第7期45卷 643-649页

作者： XU Yigangguangzhou institute of geochemistry, chinese {4. of sciences, guangzhou 51064., china guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou China

Leaching experiment has been carried out on mantle xenoliths with different petrographic features in order to directly characterize the nature of intergranular components. ICP-MS analyses of leachates show that they are characterized by high LREE concentrations with strong depletion of Ta. The total REE contents and whether the negative Rb, Ba and Nb anomalies are present or not in intergranular components are largely dependent upon the nature of mantle metasomatism experienced by its host rock. It is proposed that intergranular components may represent residues of small volume metasomatic melts.

关键词： peridotite xenoliths intergranular components trace elements upper mantle.

Relation between texture and chemical composition of peridotite xenoliths and its implications: An example from Wangqing, Jilin Province

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chinese Science Bulletin 1998年第10期43卷 837-840页

作者： XU Yigang guangzhou institute of geochemistry, chinese {4. of sciences, guangzhou 51064., china guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou China

Spinel peridotite xenoliths from Wangqing, NE china exhibit correlative variations in texture, temperature, geochemistry and radiogenic isotopes. This suggests that the Wangqing xenoliths may come from a mantle diapir. It is possible that the fertile and undeformed lherzolites were situated in the interior of the diapir, whereas the refractory and deformed harzburgites and clinopyroxene_poor lherzolites were within the diapiric flanks.

关键词： peridotite xenoliths texture geochemistry Wangqing.

Superlarge ore deposits and development of china's mineral resources

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chinese Science Bulletin 1999年第15期44卷 1436-1440页

作者： ZHAO Zhenhuaguangzhou institute of geochemistry , chinese academy of sciences , guangzhou 51064., china Guangzhau institute of geochemistry Chinese Academy of Sciences Guangzhou China

The ever increasing demand of mineral resources in china was assessed and it is suggested that the development of superlarge ore deposits was the best way to meet such demand. Research and exploitation of superlarge ore deposits can bring great economic and social benefits to the society. It is also the best way to a better integration of resource industry development and environmental protection and therefore provides a basis of sustainable development of china. china has made important advancements in the research of superlarge ore deposits and especially in classification, selectivity and confinement of deposit types and temporal and spatial distributions. It is suggested that the metallodynamics and the interaction between the crust and the mantle and the core should be studied. At the same time, a new concept of resources should be established in order to build a new integrated system for research, and resource development and environmental proiection.

关键词： superlarge ore deposit metallodynamics resource-environmental integration.

Magnetic properties of Jiaxian red clay sequences from northern chinese Loess Plateau and its paleoclimatic significance

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Science china Earth sciences 2005年第8期48卷 1234-1245页

作者： QIANG Xiaoke, AN Zhisheng, LI Huamei, CHANG Hong & SONG Yougui 1. SKLLQG, institute of Earth Environment, chinese academy of sciences, Xi’an 710075,{4. 2. guangzhou institute of geochemistry, chinese academy of sciences, guangzhou 51064.,{4. chinese academy of sciences SKLLQG Institute of Earth Environment Xi’an China chinese academy of sciences Guangzhou Institute of Geochemistry Guangzhou China

Detailed rock magnetism investigation of the Jiaxian red clay sequences indicated that there are common magnetic mineralogy properties in red clay and loess-paleosol sequences from the chinese Loess Plateau as well as the marked properties of themselves, magnetic min-erals mainly with magnetite, maghemite, hematite, and possibly limonite/goethite contributing to the magnetic behavior. Meanwhile, it is found that the strong paleosol in red clay sequences has a lower coercivity and higher content of ultra-fine ferrimagnetic grains than that of the weak pa-leosol, which is similar to loess and paleosol in upper Wucheng Loess sequences, and indicates that humid conditions and relatively strong pedogenesis play a significant role in the increase of ultra-fine magnetic minerals and transformation of the magnetic minerals. This suggests that, like Quaternary loess-paleosols, the change of characteristics of paleoclimatic conditions of the late Tertiary red clay deposits is fluctuant. In addition, the results of magnetic hysteresis properties show that the applied saturated field for samples from the Jiaxian red clay sequences is higher than that of the samples from eastern and southern chinese Loess Plateau. It is obviously shown that there exist more hard magnetic minerals and relatively weak biochemical processes in the Jiaxian red clay sequences on northern chinese Loess Plateau. We conclude that the paleocli-matic environment is different between northern and eastern/southern chinese Loess Plateau, and it should be more arid in northern chinese Loess Plateau.

关键词： northern chinese Loess Plateau, red clay, magnetic property, paleoclimatic significance.

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2, WANG Yuejun1, FAN Weiming1, LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4.1. Key Laboratory of Isotope Geochronology and geochemistry, guangzhou institute of geochemistry, {4. academy of sciences, guangzhou 51064., china 2. Graduate University of {4. academy of sciences, Beijing 100039, china 3. SHRIMP isotope Laboratory, {4. academy of Geological sciences, Beijing 100037, china 4. institute of Geology and Geophysics, {4. academy of sciences, Beijing 100029, china Key Laboratory of Isotope Geochronology and geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of chinese academy of sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-137) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4.± 3.0 Ma and 230.4.± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U apparent age of 1977±4. Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

Nitric Oxide Emission Following Wetting of Dry Soils in Subtropical Humid Forests

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Pedosphere 2009年第6期19卷 692-699页

作者： LI De-Jun and WANG Xin-Ming 2 State Key Laboratory of Organic geochemistry, guangzhou institute of geochemistry, {4. academy of sciences, guangzhou 51064. (china) State Key Laboratory of Organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 (China)

Information about soil nitric oxide （NO） emissions from subtropical forests is quite limited, and even less is known about the pulse emission of NO when wetting soils after a long period of dryness. In this study, we measured NO fluxes following wetting of dry soft in a broadleaf forest and a pine forest in subtropical china. Large pulses of NO fluxes were observed after soil wetting in both forests. NO fluxes increased significantly within 0.5 h following wetting in both forests and reached peak 1 and 4.h after soil wetting in the pine forest and the broadleaf forest, respectively. In the broadleaf forest, averaged peak flux of NO pulses was 157 ng N m^-2 s^-1, which was 8 times the flux value before wetting, and in the pine forest, the averaged peak flux was 135 ng N m-2 s 1, which was 15.5 times the flux value before wetting. The total pulses-induced NO emissions during the dry season were roughly estimated to be 29.4.mg N m^-2 in the broadleaf forest and 22.2 mg N m^-2 in the pine forest or made up a proportion of 4.6% of the annual NO emission in the broadleaf forest and 5.3% in the pine forest.

关键词： dry season flux. NO. pulse subtropical china

^(4.)Ar/^(39)Ar chronology and geochemistry of high-K volcanic rocks in the Mangkang basin, Tibet

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Science china Earth sciences 2005年第1期48卷 1-12页

作者： ZHANG Huihua, HE Huaiyu, WANG Jianghai & XIE Guanghong guangzhou institute of geochemistry, chinese {4. of sciences, guangzhou 51064., china institute of Geology and Geophysics, chinese {4. of sciences, Beijing 100029, china College of Life sciences, Sun Yat-Sen University, guangzhou 510275, china chinese academy of sciences Guangzhou Institute of Geochemistry Guangzhou China chinese academy of sciences Institute of Geology and Geophysics Beijing China College of Life sciences Sun Yat-Sen University Guangzhou China

Our two newly obtained high-quality 4.Ar/39Ar ages suggest that the high-K volcanic rocks of the Lawuxiang Formation in the Mangkang basin, Tibet were formed at 33.5 ( 0.2 Ma. The tracing of elemental and Pb-Sr-Nd isotopic geochemistry indicates that they were derived from an EM2 enriched mantle in continental subduction caused by transpression. Their evidently negative anomalies in HFSEs such as Nb and Ta make clear that there is an input of continental material into the mantle source. The high-K rocks at 33.5 ( 0.2 Ma in the Mangkang basin may temporally, spatially and compositionally compare with the early one of two-pulse high-K rocks in eastern Tibet distinguished by Wang J. H. Et al., implying that they were formed in the same tectonic setting.

关键词： Cenozoic high-K volcanic rocks, 4.Ar/39Ar chronology, Mangkang basin, Tibet.

PREPARATION AND PROPERTIES OF ETHYL-CYANOETHYL CELLULOSE/POLYACRYLIC ACID COMPOSITE FILMS WITH REFLECTION COLORS

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chinese Journal of Polymer Science 2001年第3期19卷 277-282页

作者： Yong Huang institute of Chemistry, chinese academy of sciences, Beijing 100080{4. Laboratory of Cellulose and Lignocellulosics Chemistry guangzhou institute of Chemistry chinese academy of sciences, guangzhou 510650,{4. 中科院化学所北京

Ethyl-cyanoethyl cellulose [(E-CE)C]/acrylic acid (AA) becomes a cholesteric liquid crystalline solution withvivid colors when the (E-CE)C concentration is 4. wt%～52 wt%. (E-CE)C/polyacrylic acid (PAA) composites withcholesteric structure were prepared by polymerzing AA in (E-CE)C/AA liquid crystalline solutions. The layers of orderedpolymer chains in the cholesteric phase were inclined during polymerization and the degree of the inclination depended onthe polymerization temperature and the concentration of the solution before polymerization. The cholesteric structure in thecomposites could not be changed when temperature was lower than 100℃. Cross-linking of the PAA in compositesimproved their water-resistance. The cholesteric order of the composites without cross-linking was destroyed when theywhere immersed in water. The color derived from the selective reflection of the cholesteric phase of the cross-linkedcomposites turned from blue to red after the composites absorbed water. The color of the composites could be returned to theoriginal one when the absorbed water was removed from the swollen composites.

关键词： Cholesteric structure Composites Selective reflection Liquid crystalline solutions

Advances in the study of current-use non-PBDE brominated flame retardants and dechlorane plus in the environment and humans

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Science china Chemistry 2010年第5期53卷 961-973页

作者： LUO XiaoJun,CHEN SheJun,MAI BiXian & FU JiaMo State Key Laboratory of Organic geochemistry guangzhou institute of geochemistry,{4. academy of sciences,guangzhou 51064.,china State Key Laboratory of Organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

The fate of the high production volume,currently in use,and not regulated non-polybrominated diphenyl ether(PBDE) flame retardants,such as tetrabromobisphenol A(TBBPA) ,hexabromocyclododecane(HBCD) and dechlorane plus(DP),and the alternative flame retardants of PBDE,such as BTBPE and DBDPE,in the environment has attracted increasing attention and aroused concern due to the increasing regulation and phasing-out of *** paper reviews the distribution,bioaccumulation,human exposure and environmental behavior of those non-PBDE flame retardants in various environmental *** data gaps and needs for future research are discussed.

关键词： TBBPA HBCD BTBPE DBDPE DP