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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 51064., 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.

Alkalic-type epithermal gold mineralization associated with Tongshi complex in Pinyi County, Shandong Province

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chinese Science Bulletin 1999年第S2期44卷 236-238页

作者： XIONG Xiaolin, zhao Zhenhua and WANG Qiang guangzhou institute of geochemistry, chinese academy of sciences, guangzhou 51064., china guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou 510640 China

THE alkali-rich subvolcanic complex of Tongshi and the associated gold mineralization are located at thesouth boundary of Pinyi Mesozoic volcanic depression in western Shandong Province. There are morethan 30 gold deposits and mineralization locations around the complex, in which Guilaizhuang gold deposit and Zhuojiazhuang bonanza gold deposit with important economic value are included. This area isbecoming a perspective target of superlarge gold deposit. In the mine area, there crop out Archeangranitic gneisses, Paleozoic carbonates and Jurassic clastic rocks, which was intruded by Tongshi complexwith 30 km. The complex consists of K-high igneous rocks formed by two stages of magmatism. In thefirst stage, the monzonitic dioritic porphyrys, which belong to K-high calc-alkalic rocks, were formed andin the second stage, monzonitic-syenitic porphyrys, which belong to K-high alkalic rocks, were *** Ar-Ar ages are 189 Ma and 188 Ma, respectively. At the end of the second stage, a lot of theexplosive breccias were formed. The gold mineralization in this area is closely associated in time andspace with the second stage monzonitic-syenitic porphyrys. Based on the characteristics of

关键词： epithermal gold mineralization Tongshi complex Pinyi County Shandong Province.

Evaluation criteria for gas source rocks of marine carbonate in china

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Progress in Natural Science:Materials International 2005年第9期15卷 810-817页

作者： WANG zhaoyun1**, zhao Wenzhi1 and WANG Yunpeng2(1. Research institute of Petroleum Exploration & Development,Petrochina, Beijing 100083, china 2. guangzhou institute of geochemistry, chinese academy of sciences, guangzhou 51064., china) Research institute of Petroleum Exploration and Development PetroChina Beijing 100083 China guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Hydrocarbon generating and expulsion simulation experiments are carried out using samples artifically matched between the acid-dissolved residue of relatively low-maturity limestone and the original sample. This work makes up for the insufficiency of source rock samples with high abundance of organic matters and low maturity in china. The organic carbon content of the 10 prepared samples varies between 0.15% and 0.74%. Pyrolysis data and simulation experiment results of hydrocarbon generating and expulsion, which were obtained by a high-temperature and high-pressure open system, indicate that the lower limit of organic carbon content for marine carbonate rock to generate and expel hydrocarbons is 0.23%—0.31%. In combination with the numerical analysis of organic carbon in marine carbonate rocks from Tarim Basin, Sichuan Basin, Ordos Basin and North china, as well as the contribution of these gas source rocks to the discovered gas pools, we think that the organic carbon criterion for carbonate gas source rocks should be 0.3%.

关键词： carbonate gas source rock gas-generating efficiency evaluation criteria simulation experiment.

High-nitrogen and low-irradiance can restrict energy utilization in photosynthesis of successional tree species in low subtropical forest

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Science china(Life sciences) 2008年第7期51卷 592-603页

作者： CAI Xi’An,SUN GuChou,zhao Ping &LIU XiaoJing South china institute of Botany,chinese academy of sciences,guangzhou 510650,china South china institute of Botany Chinese Academy of Sciences Guangzhou China

Responses of photosynthesis and the partition of energy utilization to high-nitrogen importation and high-light intensity in leaves of three dominant tree species of subtropical forest,including sun plant or early-successional species Schima superba,mesophyte or intermediate-successional species Canstanopsis hystrix,and shading-tolerant plant or late-successional species Cryptocarya concinna were studied by using the CO2 exchange system and chlorophyll fluorescence *** results showed that,regardless of plant species,net photosynthetic rate(Pn)was higher in high-nitrogen supply and high irradiance(HNHL)plants than in low-nitrogen supply and high irradiance(LNHL)plants,implying that low-nitrogen importation would limit Pn of plants grown under high ***, high-nitrogen supply and low irradiance(HNLL)plants had a lower *** change of quantum yield(Fv′/Fm′)in opened PS II was found in leaves of HNHL,LNHL or HNLL plants of *** and C. hystrix,while a higher Fv′/Fm′occurred in HNHL plants of *** in comparison with LNHL or HNLL *** HNHL plants of *** also had a higher photochemical quantum yield(△F/Fm′) than LNHL or HNLL plants,however no similar responses were found in plants of *** and C. hystrix(P0.05)and it was significantly higher than in HNLL plants(P<0.05).*** also had a similar response inφ PSII to nitrogen supply and *** of species HNLL plants had a significantφ PSII and higher heat dissipation in light,and this effect was more severe in *** than in *** or *** results may mean that high-nitrogen importation by nitrogen deposit and low irradiance caused by changing climate or air pollution would more severely restrict photosynthetic processes in the late-succ

关键词： low subtropical forest successional plant high nitrogen concentration partition of photosynthetic energy

Differential expression analysis of Liprin-α2 in hibernating bat (Rhinolophus ferrumequinum)

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Progress in Natural Science:Materials International 2008年第1期18卷 27-32页

作者： Lihong Yuan a,b,c, Xueguo Zuo a, Jinping Chen d, Benfu Lin e, Junpeng Zhang b, Min Sun e, Shuyi Zhang a,* a School of Life Science, East china Normal University, Shanghai 200062, china b institute of Zoology, chinese academy of sciences, Beijing 100080, china c Graduate University of chinese academy of sciences, Beijing 100080, china d Guangdong Entomological institute, guangzhou 510260, china e guangzhou institute of Biomedicine and Health, chinese academy of sciences, guangzhou 510663, china School of Life Science East China Normal University Shanghai 200062 China institute of Zoology Chinese Academy of Sciences Beijing 100080 China Graduate University of chinese academy of sciences Beijing 100080 China Guangdong Entomological institute Guangzhou 510260 China guangzhou institute of Biomedicine and Health Chinese Academy of Sciences Guangzhou 510663 China

A PCR-based subtractive hybridization technique was used to identify genes up-regulated in the hibernating bat brain to explore the molecular mechanism of hibernation. Three genes, Liprin-a2, PTP4A2 and CAMKKb were difierentially expressed in hibernating bat brain tissue compared to active bat brain tissue. One of them, Liprin-a2, which has recently been shown to have the key function in the organization of presynaptic and postsynaptic multiprotein complexes was studied in detail. We demonstrated that the expression level of Liprin-a2 was up-regulated almost 4-fold in hibernating bat brains by RT-PCR compared to levels in active bats. The difierential expression pattern of Liprin-a2 was also detected in muscle, fat, brain and heart tissue of hibernating bats by real-time quantitative PCR. The result indicated that Liprin-a2 was over-expressed in brain and heart tissue and down-regulated in muscle and fat. In brain tissue of hibernating bats, Liprin-a2 expression was statistically significantly higher than in brain tissue of active controls (P = 0.029). The precise control of transcriptional level and the distinctively difierential expression pattern of Liprin-a2 in difierent organs during circ- annual hibernation may have important physiological significance, not only in maintaining normal function of many key organs but also in effectively conserving limited energy resources without physiological damage.

关键词： Bat Differential expression Hibernation Liprin-a2

Discovery of Permian island-arc basalts in the Cenxi area and the tectonic significance──A piece of evidence for the paleo-Tethyan tectonic belt in western Guangdong and eastern Guangxi

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chinese Science Bulletin 1998年第21期43卷 1838-1842页

作者： ZHANG Boyou 1, zhao Zhenhua 1, SHI Manquan 1, YANG Shufeng 2 and CHEN Hanlin 2 1. guangzhou institute of geochemistry, chinese academy of sciences, guangzhou 51064., china 2. Department of Earth sciences, Zhejiang University, Hangzhou 310027, china guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou China Department of Earth sciences Zhejiang University Hangzhou China

Cenxi Permian basalts are the late Palaeozoic island-arc type basalts first found in South china. REE and trace element characteristics and distribution patterns show that this volcanic formation, which has been isotopically dated at 261 MaB.P. by the 39Ar/ 40Ar method, is of an active continental marginal island arc type, and that the tectonic environment at that time was an island-arc marginal sea or minor ocean basin related with the paleo-Tethyan tectonic belt in western Guangdong-eastern Guangxi.

关键词： spilite-keratophyre pillow lava Permian continental margin paleo-Tethyan evolution.

The high-resolution climate recorded in the δ^(18)O of Porites lutea from the Nansha Islands of china

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chinese Science Bulletin 2001年第24期46卷 2097-2102页

作者： YU Kefu, CHEN Tegu, HUANG Dingcheng, zhao Huanting, ZHONG Jinliang & LIU Dongsheng (LIU Tungsheng)South china Sea institute of Oceanoiogy, chinese academy of sciences. guangzhou 510301, china:Geology and Geophysics institute. chinese academy of sciences, Beijing 100029, china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China Geology and Geophysics institute Chinese Academy of Sciences Beijing China

A Porites lutea core from Yongshu Reef of Nansha Islands covering 50 years growth history was ana-ly/ed for oxygen isotopic composition with monthly and seasonally resolution. The calibration of the δ18O with the instrumental temperature indicated that the coral δ18O is a good indicator for sea surface temperature (SST) and air temperature (t). It can be used to reconstruct the SST and air temperature of the Yongshu Reef sea area. In addition, the coral δ18O provides signatures for the intensity of the East Asia monsoon and it is a record for the activities of El Nino events. With the calibrated SST and air temperature formulas, the most recent fifty years SST and air temperature were reconstructed based on the coral δ18O, thus back up the understanding of the climate of Nansha Islands to 1950. far beyond the limit of the instrumental recording since September 1988. It was found that, in general, increasing 1℃ air temperature results in 0.24‰decrease in skeletal δ18O.

关键词： Nansha Islands Porites lutea δ18O sea surface tem-perature East Asia monsoon.

Loss of energetic particles due to feedback control of resistive wall mode in HL-3

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Plasma Science and Technology 2024年第10期26卷 17-28页

作者： Yifei zhao Yueqiang LIU guangzhou HAO Zhengxiong WANG Guanqi DONG Shuo WANG Chunyu LI Guanming YANG Yutian MIAO Yongqin WANG Dalian University of Technology Dalian 116024People’s Republic of China General Atomics San Diego CA 92186-5608United States of America Southwestern institute of Physics Chengdu 610041People’s Republic of China

Effects of three-dimensional(3D)magnetic field perturbations due to feedback control of an unstable n=1(n is toroidal mode number)resistive wall mode(RWM)on the energetic particle(EP)losses are systematically investigated for the HL-3 *** MARS-F(Liu et al 2000 *** 73681)code,facilitated by the test particle guiding center tracing module REORBIT,is utilized for the *** RWM is found to generally produce no EP loss for cocurrent particles in *** the same perturbation level at the sensor location for the close-loop system,feedback produces nearly the same loss of counter-current EPs compared to the open-loop *** however that the sensor signal is ten times smaller in the close-loop system than the open-loop counter part(reflecting the fact that the RWM is more stable with feedback),the counter-current EP loss is found significantly reduced in the *** of EP losses occur only for particles launched close to the plasma edge,while particles launched further away from the plasma boundary experience much less *** strike points of lost EPs on the HL-3 limiting surface become more scattered for particles launched closer to the plasma *** into account the full gyro-orbit of particles while approaching the limiting surface,REORBIT finds slightly enhanced loss fraction.

关键词： energetic particles resistive wall mode HL-3

Identification and analysis of shear waves recorded by three-component OBSs in northeastern South china Sea

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Progress in Natural Science:Materials International 2008年第2期18卷 181-188页

作者： Minghui zhao ,Xuelin Qiu,Shaohong Xia,Ping Wang,Kanyuan Xia,Huilong Xu Key Laboratory of Marginal Sea Geology,South china Sea institute of Oceanology,chinese academy of sciences,guangzhou 510301,china Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

Structure models associated with P-and S-wave velocities contain considerable amount of information on lithology and geophysical properties,which can be used to better understand the complexity of the deep crustal structure. However,records of converted shear waves are less due to the speciality of seismic survey at sea and the rigorous generated conditions. The study on shear waves has always been a weakness for studying the deep crustal structures of South china Sea (SCS). In this paper,eleven three-component OBSs were deployed along the Profile OBS-2001 in northeastern SCS. After the data processing of polarization and band-pass filter,converted S-wave phases were identified in the radical component records of nine OBSs. Taking the OBS7 as an example,identification and analysis of converted shear waves were presented and discussed in detail. A few phase groups,such as PwSc,PgSs,PnSc,PmS,and PwSn,were found coming from the deep crust or Moho interface by simple theoretical model calculation and ray-tracing simulation. The results not only provide the underlying basis for studies of S-wave velocity structure and Poisson’s ratio structure,but also reveal the relationship between crustal petrology and seismology,which will be of importance for making full use of S-wave information in the future.

关键词： Converted shear wave Deep crustal structure Three-component ocean bottom seismometer Northeastern South china Sea