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Aoyitake plagiogranite in western Tarim Block, NW china: Age, geochemistry, petrogenesis and its tectonic implications

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Science china Earth sciences 2006年第11期49卷 1121-1134页

作者： ZHANG Chuanlin1,2. YU Haifeng3, YE Haimin2. ZHAO Yu2.& ZHANG Dongsheng4 1. Key Laboratory of Isotope Geochronology and geochemistry, guangzhou {2. of geochemistry, chinese academy of sciences, guangzhou 510640, china 2. Nanjing {2. of Geology and Mineral Resources, Nanjing 2.0016, china 3. Tianjin {2. of Geology and Mineral Resources, Tianjin 300170, china 4. The 2.d Regional Geological Investigation Party, Xinjiang Bureau of Geology and Mineral Resources, Changji 831100, china Key Laboratory of Isotope Geochronology and geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Nanjing institute of Geology and Mineral Resources Nanjing China Tianjin institute of Geology and Mineral Resources Tianjin China The 2.d Regional Geological Investigation Party Xinjiang Bureau of Geology and Mineral Resources Changji China

SHRIMPP U-Pb zircon age and geochemical and Nd isotopic data are reported for the Aoyitake plagiogranite in western Tarim Block, NW china. The plagiogranite intruded the Middle Pro- terozoic and Lower Carboniferous with an exposure area of ca. 60 km2.and crystallized at 330.7±4.8 Ma. Rock types mainly include tonalite, trondhjemite and minor amounts of diorite and quartz-diorite. Feldspars in the rocks are dominated by oligoclase-andesine, and minor perthite observed locally. The granites are sodic with Na/K ratios (molar) between 4 and 87. Total REE (50-2.0 ppm) show a clear positive correlation with SiO2. There is no LRRE/HREE fractionation (LaN/YbN=0.5-1.5), me- dium negative Eu anomalies (δ Eu=0.3-0.6), high Y content and low Sr/Y ratio (~1.0). These granites exhibit relatively juvenile Nd T2.M model ages of 470 to 580 Ma and positive εNd(331 Ma) values of 6.2. to 7.65. The aforementioned characteristics are similar to those of ocean island or ocean ridge plagiogranites. However, the regional geology, especially its scale, precludes that the plagiogranite pluton was derived directly from fractionational crystallization of mantle-derived basaltic magma. We interpreted that the primary magma of the pluton might be tonalitic in composition generated by ca. 50% partial melting of the juvenile basaltic crust. The primary magma experienced intensive frac- tionational crystallization, and intruded into the middle to upper crusts to form the granite pluton. In combination with the previous regional geological data, it is concluded that the plagiogranite pluton was emplaced within the Tarim Block in respond to the Carboniferous continental rifting along the Tianshan orogenic belt.

关键词： western Tarim, Aoyitake plagiogranite, age, geochemistry, tectonic implications.

The pathway of the interdecadal variability in the Pacific Ocean

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chinese Science Bulletin 2000年第17期45卷 1555-1561页

作者： WANG Dongxiao & LIU Zhengyu1. South china Sea institute of Oceanology,{2., guangzhou 510301, china 2. Department of Atmospheric & Oceanic sciences, University of Wisconsin-Madison, Madison, WI 53706, USA Correspondence should be addressed to Wang Dongxiao South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China Department of Atmospheric & Oceanic sciences University of Wisconsin-Madison Madison USA

Cases of the interdecadal variability in the Pacific Ocean and their evolution were examined in the paper with the statistic methods (CEOF and composite analysis) over the period of 1950-1993. Observations of oceanic temperatures in the upper 400 m revealed an obvious region of the interdecadal signals in the central North Pacific. Such signals propagated south westward, then subducted to the subtropics. The hypothesized link for interdecadal oceanic variability between the subtropics and the tropics, especially with the western tropical Pacific was unraveled in order to detect the cause of decadal signals in the tropics. The thermal anomalies subducted in the central North Pacific east to the dateline only reach 18°N. There has been no further southward propagation since then due to a certain barrier. The origin of the interdecadal signals in the western tropical Pacific was traced to the southern tropical Pacific. There is a meridional pathway around the dateline where the signals were loaded.

关键词： interdecadal oceanic variability southern tropical Pacific signal pathway.

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,{2. 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(P2.00μmol photon·m -2.s -1,the fraction of energy consumed by photochemistry(φ PSII )was 18.2.in LNHL plants of *** which was higher than that in HNHL plants(P>0.05)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

Impacts of Typhoons Tianying and Dawei on seagrass distribution in Xincun Bay,Hainan Province,china

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Acta Oceanologica Sinica 2011年第1期30卷 32-39页

作者： YANG Dingtian HUANG Daojian CAS key Laboratory of Tropical Marine Environmental Dynamics South China Sea Instituteof Oceanology Chinese Academy of Sciences Guangzhou 510301 China South china institute of Environmental {2. Ministry of Environmental Protection of thePeople＇s Republic of China Guangzhou 510655 China

More than 50% of the typhoons landing in china have landed on the southeast coast, where they have caused great pressure on the coastal environment. Seagrass, one of the most important con- stituents of coastal ecosystems, is also greatly affected by typhoons. In order to clarify how seagrass distribution variation is affected by typhoons in coastal areas in southeast china, data of Typhoons Dawei and Tianying （category 4 and category 2.respectively, which just ran through the southern part of Hainan province） have been studied. In situ observation and satellite remote sensing data （CBERS-{2. Brazil Earth Resources Satellite） in 2.04 and 2.06 were used to retrieve seagrass distribution in Xincun Bay, Hainan province. In situ observations showed that leaf length, stem biomass and above ground biomass on average showed evidence of reduction after Typhoons Tiany- ing and Dawei. However, seagrass density showed no evidence of reduction after typhoon Tianying and Dawei passed by and increased rapidly in January 2.06. From results of satellite remote sensing data, seagrass distribution can be detected with high accuracy, and the area of seagrass distribution on the south coast of Xincun Bay in 2.06 after the typhoon passed by was smaller than that in 2.04 in region A and B. However, in region C, area of seagrass coverage under 2.% increased. These results demonstrated that typhoons Tianying and Dawei damaged seagrass bed and helped seagrass to get rid of aged and dead leaves, and this correspondingly facilitated seagrass growth.

关键词： seagrass Typhoon Tianying and Dawei Xincun Bay

On designated-weight Boolean functions with highest algebraic immunity

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Science china Mathematics 2010年第11期53卷 2847-2854页

作者： LIU MeiCheng1,3, DU YuSong2. PEI DingYi2.& LIN DongDai1 1The State Key Laboratory of Information Security, institute of Software of chinese academy of sciences, Beijing 100190,{2. 2.ollege of Mathematics and Information sciences, guangzhou University, guangzhou 510006,{2. 3Graduate University of chinese academy of sciences, Beijing 100049,{2. The State Key Laboratory of Information Security Institute of Software of Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China College of Mathematics and Information sciences Guangzhou University Guangzhou China

Algebraic immunity has been considered as one of cryptographically significant properties for Boolean functions. In this paper, we study ∑d-1 i=0 (ni)-weight Boolean functions with algebraic immunity achiev-ing the minimum of d and n - d + 1, which is highest for the functions. We present a simpler sufficient and necessary condition for these functions to achieve highest algebraic immunity. In addition, we prove that their algebraic degrees are not less than the maximum of d and n - d + 1, and for d = n1 +2.their nonlinearities equalthe minimum of ∑d-1 i=0 (ni) and ∑ d-1 i=0 (ni). Lastly, we identify two classes of such functions, one having algebraic degree of n or n-1.

关键词： cryptography Boolean function algebraic immunity algebraic degree nonlinearity

Track Fading and Its Applications in Archaeology, Tectonics and Geothermal Chronology in china

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Journal of Earth Science 2013年第4期24卷 645-651页

作者：郭士伦袁万明陈宝流黄慰文刘顺生 Department of Nuclear Physics China Institute of Atomic Energy School of Earth sciences and Resourses China University of Geosciences Department of Radioisotopes China Institute of Atomic Energy institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences guangzhou institute of {2. Chinese Academy of Sciences

Track fading is a basic phenomenon in track science and has been the source of informa- tion in geosciences. This article summarizes the knowledge of track fading and gives some examples of successful applications of track fading in archaeology, tectonics and geothermal chronology in china. The applications of track fading are classified into 5 modes：（1） mode of complete fading （annealing）; （2. mode of partial fading; （3） use of the dependence of track fading on time and temperature; （4） use of the differences of track fading between coexisting minerals; and （5） use of fading-reduced track length. Track fading mechanisms hints that scientists in geothermal chronology should adopt microprobes for quantitative elemental analysis to determine the detailed chemical compositions of each mineral grain or at least of the grains from each position of geological structures in order that one becomes well aware of the relation between the track fading behavior and chemical compositions of the mineral used.

关键词： track fading archaeology tectonics geothermal chronology.

Fouling in offshore areas southeast of the Zhujiang(Pearl)River Delta,the northern South china Sea

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Acta Oceanologica Sinica 2003年第2期22卷 201-212页

作者： Yan Tao, Yan Wenxia, Dong Yu, Liang Guanhe, Yan Yan, Wang Huajie South china Sea institute of Oceanology,{2. academy of sciences,guangzhou 510301,china. South china Sea Inst. of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

In order to understand the type and extent of marine fouling in offshore areas southeast ofthe Zhujiang (Pearl) River delta, within the period form May 1986 to June 1987, two biological buoys were deployed at water depths of 95 m and 113 m located in 114 km and 160 km off the coast of Hong Kong, respectively. Moreover, the fouling community of a Marex hydrological buoy located in 115 m depth water 172.km off Hong Kong was also surveyed. The results show that a total of 78 species were collected and identified. The panels exposed for 3 months were mainly dominated by stalked barnacles Conchoderma hunteri and Lepas anatifera and hydroids Orthopyxis sp. As for the buoys, including the subsurface buoy, and their mooring systems exposed for 6 and 12.months, respectively, some hard foulers such as common oysters, pearl oysters, acorn barnacles and bryozoans were also found. The compositions of fouling communities also varied greatly with depth.

关键词： Biofouling offshore structures the South china Sea

THE EVOLUTIONARY HISTORY OF THE WEST KUNLUN MOUNTAINS: A TECTONIC RECONSTRUCTION BASED ON STUDIES OF MAGMATISM

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地学前缘 2000年第S1期7卷 262-263页

作者： Yuan Chao 1,2., Sun Min 2. Li Jiliang 3[WT5,5”BX](1 guangzhou institute of {2., chinese academy of sciences, guangzhou 510640,china 2.Department of Earth sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, china 3.Institut

The Kunlun Mountains is situated in the north margin of the Tibetan plateau and is one of crucial areas for unraveling the tectonic evolutionary history of the plateau and Eurasia. However, there is no widely accepted model for this area. One of the reasons is that some basic issues for the tectonic reconstruction have not been well settled, they are: (1) Is the Kunlun Mountains an ancient accretion prism, or a mini continent with old basement?(2. What is the age of the Kudi ophiolite, early Paleozoic or late Paleozoic?(3) When did the South Kunlun Block accrete to the Tarim Block?(4) Do the fifth and the forth sutures represent different oceans, or they are just the chronologically different relics of the same ocean?(5) Did the Kunlun Mountains experience continuous subduction since Neoproterozoic?(6) When did the Paleo\|Tethys closed in the West Kunlun range?

关键词： West Kunlun Mountains Proto\|Tethys Paleo\|Tethys boninite series rocks accretion prism magmatic gap tectonic reconstruction

Model Test and Design of the Wave Energy System on "Central Fairway No. 1" Light Ship

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china Ocean Engineering 1992年第3期7卷 351-360页

作者： Gao Xiangfan , Liang Xianguang Jiang Niandong Feng Manzhi Wang Wei Senior Engineer, guangzhou institute of Energy Conversion,{2., 510070 guangzhouAssociate Professor, guangzhou institute of Energy Conversion,{2., 510070 guangzhou Engineer, guangzhou institute of Energy Conversion,{2., 510070 guangzhou

This paper presents the test of a ship model for the design of a backward-bent duct oscillating water column type wave energy conversion system, to supply electric power for a light ship. This system suggests a new wa... 详细信息

关键词： model test wave energy oscillating water column (OWC) light ship wave-activated generator