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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,chinese academy of sciences.guangzhou 510640,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

^(40)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 academy of sciences. guangzhou 510640, china institute of Geology and Geophysics, chinese academy 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 40Ar/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, 40Ar/39Ar chronology, Mangkang basin, Tibet.

Magmatic-hydrothermal Evolution and Mineralization Mechanisms of the Wangjiazhuang Cu(-Mo)Deposit in the Zouping Volcanic Basin,Shandong Province,china:Constraints from Fluid Inclusions

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 679-700页

作者： SHU Lei YANG Renchao SHEN Kun YANG Deping MAO guangzhou LI Min LIU Pengrui MA Xiaodong Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdaoShandong 266590China Key Laboratory of Gold Mineralization Processes and Resource Utilization MNR/Key Laboratory of Metallogenic Geological Processes and Resource UtilizationShandong Province/Shandong Institute of Geological SciencesJinan 250013China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdaoShandong 266237China

The Wangjiazhuang Cu(-Mo)deposit,located within the Zouping volcanic basin in western Shandong Province,china,is unique in this area for having an economic *** order to expound the metallogenetic characteristics of this porphyry-like hydrothermal deposit,a detailed fluid inclusion study has been conducted,employing the techniques of representative sampling,fluid inclusion petrography,microthermometry,Raman spectroscopy,LA-ICP-MS analysis of single fluid inclusions,as well as cathode fluorescence spectrometer analysis of host mineral *** deposit contains mainly two types of orebodies,***-dissemination-stockwork orebodies in the K-Si alteration zone and pegmatiticquartz sulfide veins above *** addition,minor breccia ore occurs *** types of fluid inclusions in the deposit and altered quartz monzonite are identified:L-type one-or two-phase aqueous inclusions,V-type vapor-rich inclusions with V/L ratios greater than 50%-90%,D-type multiphase fluid inclusions containing daughter minerals or solids and S-type silicate-bearing fluid inclusions containing mainly muscovite and *** petrography and fluid inclusion study has revealed a three-stage mineralization process,driven by magmatic-hydrothermal fluid activity,as ***,a hydrothermal fluid,separated from the parent magma,infiltrated into the quartz monzonite,resulting in its extensive K-Si alteration,as indicated by silicate-bearing fluid inclusions trapped in altered quartz *** is followed by the early mineralization,the formation of quartz veinlets and dissemination-stockwork *** the main mineralization stage,due to the participation and mixing of meteoric groundwater with magmatic-sourced hydrothermal fluid,the cooling and phase separation caused deposition of metals from the hydrothermal *** a result,the pegmatitic-quartz sulfide-vein ores *** the late mineralization stage,decreasing fluid salinity led to the formation of L-type aqueous

关键词： fluid inclusions fluid immiscibility mineralization mechanisms Wangjiazhuang Cu(-Mo)deposit

The biomarkers of 2,6,10,15, 19-pentamethylicosenes and their carbon isotopic composition in the sediments from the Gulf of Mexico

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chinese Science Bulletin 2006年第14期51卷 1736-1740页

作者： SONG Zhiguang1,2 & WANG Cuiping1,31. State Key Laboratory of Organic geochemistry, guangzhou institute of geochemistry, chinese academy of sciences. guangzhou 510640, china 2. guangzhou Research Center of Gas Hydrate, chinese academy of sciences. guangzhou 510640, china 3. Graduate School of chinese academy of sciences. Beijing 100039, china State Key Laboratory of Organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China guangzhou Research Center of Gas Hydrate Chinese Academy of Sciences Guangzhou China Graduate School of chinese academy of sciences Beijing China

A group of 2,6,10,15,19-pentamethyli- cosenes (PMIΔ) containing 1―5 unsaturated double bonds has been identified in the sea floor sediments from the Gulf of Mexico at the Green Canyon 238 *** PMIΔ compounds are distributed between nC22 and nC24 on the mass chromatogram of aliphatic fraction. Their δ 13C values are very much depleted in 13C and in the range of ?86.7‰ to ?115.5‰, whereas the δ 13C values of companion n-alkanes range from ?28.4‰ to ?34.6‰. These unsaturated PMIΔ com-pounds are typical biomarkers derived from the an-aerobic oxidation of methane mediated by meth-ane-oxidizing archaeal bacteria and indicative of the gas seeps or even the occurrence of gas hydrates in the deep sea sediments.

关键词：生物标志墨西哥湾沉积物 PMIA 天然气水化物

Oxygen and hydrogen isotopic compositions of coexistent minerals of the Tasigake alkali granite pluton,northern Xinjiang:constraints upon the cause of ^(18)O-D depletion and the ^(18)O/^(16)O exchange kinetics

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chinese Science Bulletin 1999年第12期44卷 1086-1093页

作者： LIU Wei, ZHAO Zhenhua ZHANG Fuqin Research Center of Mineral Resources Exploration, institute of Geophysics , chinese academy of sciences., Beijing 100101, china guangzhou institute of geochemistry, chinese academy of sciences., guangzhou 510640, china Research Center of Mineral Resource Exploration Institute of Geophysics Chinese Academy of Science Beijing China guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou China

Oxygen and hydrogen isotopic compositions have been determined of three coexistent mineral triplets of alkali feldspar, quartz, arfvedsonite of 11 samples collected from the Tasigake alkali granite pluton, Ulungur River region, northern Xinjiang. Isotopic exchange with meteoric water during subsolidus cooling caused strong 18O-D depletion and the remarkable nonequilibrium 18O/16O relation between coexistent minerals. 18O/16O exchange kinetic effects of the three minerals are simultaneously and consistently modelled. Exsolution and microtextural reorganization of alkali feldspar, and infiltration of water have been mutually facilitated by each other. Shallow intrusion, and circulation of meteoric water throughout the pluton cool it effectively. As a result, the "heat engine" is rapidly extinguished, and the nonequilibrium 18O/16O relation is frosen.

关键词： 18O-D depletion isotopic exchange kinetics alkali granite Ulungur.

Stage characteristics for the development of late Quaternary paleosols in the Yangtze Delta area

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chinese Science Bulletin 1999年第9期44卷 857-860页

作者： CHEN Qingqiang and LI CongxianLaboratory of Marine Geology , Tongji University , Shanghai 200092, china guangzhou institute of geochemistry , chinese academy of sciences., guangzhou 510640, china Laboratory of Marine Geology Tongji University Shanghai China guangzhou Institue of geochemistry Chinese Academy of Sciences Guangzhou China

The late Quaternary paleosols in the Yangtze Delta area developed in the period of 25 000—12 000 aBP. Phytolith ratios (value A) of contents of fan, square and rectangle types indicaring the warm and humid climate to those of bar, hat and point types indicating cold and dry climates decrease upwards overall on profiles of the paleosols, suggesting that the climates turned from warm and humid to cold and dry. So, the paleosols developed mainly during the regression before the last glacial maximum. Changes of value A indicate no trend of warming, suggesting that the transgression was rapid after the last glacial maximum. The development of the paleosols exhibited obvious stages, which were controlled remarkably by transgression and regression: Ⅰ. Period of alternation of deposition and pedogenesis, which was from the occurrence of regresson before the last glacial maximum to the time when sea levels fell close to the lowest;Ⅱ. Exposure period with continual pedogenesis, which was terminated when the

关键词： paleosol phytolith development processes late Quaternary Yangtze Delta.

Eclogites in the interior of the Tibetan Plateau and their geodynamic implications

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chinese Science Bulletin 2009年第15期54卷 2556-2567页

作者： ZHANG KaiJun1,2 & TANG XianChun2,3 1 Department of Earth sciences. Nanjing University, Nanjing 210093, china 2 guangzhou institute of geochemistry, chinese academy of sciences. guangzhou 510640, china 3 Graduate University of chinese academy of sciences. Beijing 100049, china Department of Earth sciences Nanjing University Nanjing China guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of chinese academy of sciences Beijing China

Eclogites have been recently reported in the interior of the Tibetan Plateau, including in the central Qiangtang metamorphic belt, in the Basu metamorphic massif of the eastern Bangong-Nujiang suture zone, and at Songdo and Pengco in the eastern Lhasa terrane. Some typical ultrahigh-pressure (UHP) metamorphic phenomena, e.g., garnet exsolution from clinopyroxene, were documented in the Basu and Pengco eclogites. The UHP metamorphism in the interior of the Tibetan Plateau marked by these eclogites generally took place in the Early Mesozoic. Along with exhumation of these eclogites, (post-) collision-related magmatism extensively occurred around the central Qiangtang belt, the eastern Ban-gong-Nujiang suture zone, and the eastern Lhasa terrane. The occurrence of these Early Mesozoic ec-logites manifests an out-of-sequence evolution of the Tethys, and they could be a product of diachro-nous collision between the eastern Qiangtang terrane and the irregular continental margin of the united western Qiangtang-Lhasa plate, along the linked eastern Bangong-Nujiang-central Qiangtang zone. The collision-related magmatic rocks could have been originated from lithospheric thickening, melting, or detachment due to the collision. The presence of UHP metamorphic rocks in central Qiangtang and Basu implies likely continental deep-subduction, and the denudation of these two metamorphic zones could have served as the source of the Triassic turbidites in the Songpan-Garzê complex and the Ju-rassic turbidites in the western Bangong-Nujiang zone, respectively. However, studies of the eclogites in the interior of the Tibetan Plateau just began, and many principal aspects still remain to be explored, such as their distributions, typical lithologies and minerals, temperature-pressure conditions, timing of formation and exhumation, protoliths and tectonic setting, and relationship with the evolution of the Tethys and large-scale basins in Tibet.

关键词：地球动力学意义青藏高原榴辉岩

Noble gas and cosmic-ray exposure age of Juancheng chondrite

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chinese Science Bulletin 1999年第12期44卷 1142-1143页

作者： WANG Daode and WANG Ruitian guangzhou institute of geochemistry, chinese academy of sciences., guangzhou 510640, china Heze Bureau of Seismology, Shandong Province , Heze 274026, china guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou China Heza Bureau of Seismology Shandong Province Heze China

The analytical results of noble gase in recently fallen Juancheng chondrite indicate that cosmic-ray ages of cosmogenic nuclei of 3He, 21Ne and 38Ar are 5.1, 5.0 and 5.8 Ma, respectively, averaging 5.3 Ma. The gas retention ages radiogenic nuclei of 4He and 40Ar are 3200 and 4 200 Ma, respectively. The average cosmic-ray age shows that it has occurred at breakup of the meteoroid from its parent body by impact before 5.3 Ma.

关键词： noble gas cosmic-ray exposure age chondrite Juancheng Shandong.

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 china Laboratory of Cellulose and Lignocellulosics Chemistry guangzhou institute of Chemistry chinese academy of sciences. guangzhou 510650, china 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 42 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

Saline-alkali soil reclamation and utilization in china:progress and prospects

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 216-228页

作者： guangzhou WANG Gang NI Gu FENG Haley MBURRILL Jianfang LI Junling ZHANG Fusuo ZHANG State Key Laboratory of Nutrient Use and Management(SKLNUM) College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China The institute of Ecology and Evolution University of OregonEugeneOR97403USA

Soil salinity is a global threat to the productivity of arable land. With the impact of population growth and development of social economy in china, the area of arable land has been shrinking in recent decades and is approaching a critical threshold of 120 Mha, the minimum area for maintaining the national food security. Saline-alkaline land, as important backup reserve, has been receiving increased attention as an opportunity to expand land resources. This review first summarizes the general principles and technologies of saline soil reclamation to support plant growth, including leaching salts or blocking the rise of salts, and soil fertility enhancement to improve the buffering *** the progress in this area in china is described including the customization of technologies and practices used in different saline-alkali regions. Following the soil management strategies, the concept of selecting crops for saline soil is proposed. This encompasses halophyte planting, salt-tolerant crop breeding and the application of saline-adapted functional microorganisms to improve the adaptation of crops. Finally, the current problems and challenges are evaluate, and future research directions and prospects proposed for managing this major soil constraint.

关键词： Food security land reserve reclamation saline-alkali soil utilization