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Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze region. South China

Science China Earth Sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2, TONG Jinnan3, QIU Haiou4 & ZHAO Laishi3 1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China 2. Henan Institute of Geological Survey, Zhengzhou 450007, China 3. State Key Laboratory of Geological Processes and Mineral Resources at China University of Geosciences, Wuhan 430074, China 4. Faculty of Material Sciences and Chemical Engineering, China University of Geosciences, Wuhan 430074, China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Henan Institute of Geological Survey Zhengzhou China State Key Laboratory of Geological Processes and Mineral Resources at China University of Geosciences Wuhan China Faculty of Material Sciences and Chemical Engineering China University of Geosciences Wuhan China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze region. South China, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13C background values are intensively controlled by palaeogeographic environment. In general, δ 13C values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze region.are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze region.

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SPATIAL PATTERNING OF SPRUCE BUDWORM IN CIRCULAR region

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Science China Mathematics 1991年第6期34卷 676-688页

作者：郭本瑜 Shanghai University of Science and Technology Shanghai 201800PRC

The spatial patterning of spruce budworm in a circular region.is discussed. In particu-lar, the model with the interaction between the budworm and its predator is studied. Thepossibility of controlling outbreak states... 详细信息

关键词： spatial patterning of budworm predator circular region.

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^(40)Ar-^(39)Ar thermochronology of two ductile shear zones from Yiwulüshan,West Liaoning region. Age constraints on the Mesozoic tectonic events

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Chinese Science Bulletin 2002年第13期47卷 1113-1118页

作者： ZHANG Xiaohui, LI Tiesheng & PU ZhipingResearch Center of Mineral Resources Exploration, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100101, China Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51 Research Center of Mineral Resources Exploration Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Two ductile shear zones trending EW and NNE respectively not only controlled the tectonic framework of the northern North China, but also constrained the geody-namic background for gold mineralization in this region. Field observations and microstructural analyses reveal that the EW trending ductile shear zones are mainly contributed to dextral compressional deformation resulting from top-to-the-southeast oblique thrust shearing, whereas the NNE trending ones are genetically related to sinistral strike-slip and extensional faulting. One sample from the former yielded an 40Ar-39Ar plateau age of (219±4) Ma (Bi) and two samples from the latter gave 40Ar-39Ar plateau ages of (116± 2) Ma (Bi) and (127±3) Ma (Bi). These ages provide constraints on the top-to-the-southeast oblique thrusting event occurring in Late Triassic and the sinistral extensional and strike-slip faulting event which occurred in Early Cretaceous.

关键词： 40Ar-39Ar age biotite ductile shear zone West Liaoning region.

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A trust region.CG algorithm for deblurring problem in atmospheric image reconstruction

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Science China Mathematics 2002年第6期45卷 731-740页

作者：王彦飞袁亚湘张洪超 Stt. Key Lab. of Sci. and Eng. Comp. Inst. Compl. Math. Sci./Eng. Comp. Acad. of Math. and System Sciences Beijing 100080 China

In this paper we solve large scale ill-posed problems, particularly the image restoration problem in atmospheric imaging sciences, by a trust region.CG algorithm. Image restoration involves the removal or minimization of degradation (blur, clutter, noise, etc.) in an image using a priori knowledge about the degradation phenomena. Our basic technique is the so-called trust region.method, while the subproblem is solved by the truncated conjugate gradient method, which has been well developed for well-posed problems.The trust region.method, due to its robustness in global convergence, seems to be a promising way to deal with ill-posed problems.

关键词： image reconstruction, ill-posed problems, truncated CG, trust region.

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Studies of substrate binding region.of mEAAC1 and mASCT1 by constructing chimeras

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Chinese Science Bulletin 1999年第6期44卷 524-528页

作者： Jing Li Jibin Peng Jian Fei Fang Huang Quanbao Gu Lihe Guo Chinese Acad Sci Shanghai Inst Cell Biol Mol Cell Biol Lab Shanghai 200031 Peoples R China

The cDNA chimeras between two subtypes of mouse excitatory amino acid transporter family, mouse excitatory amino acid carrier 1 （mEAAC1） and mouse alanine serine cysteine transporter 1 （mASCT1）, were constructed by recombinant PCR. After transcription in vitro, the cRNA was injected and expressed in Xenopus laevis oocytes. 3H-Glu and 3H-Ser were used as isotopic tracer to measure the flux of amino acids. The results showed that there might not be the key amino acids responsible for substractive specificity in the NH2-terminal and its adjacent region. of these two transporters, which probably supported the formation of the substrata binding sites.

关键词： mEAAC1 mASCT1 chimeras substrate binding region.

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A 1 835 a tree-ring chronology and its preliminary analyses in Dulan region. Qinghai

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Chinese Science Bulletin 1997年第13期42卷 1122-1124页

作者： Kang, XC Graumlich, LJ Sheppard, P Lanzhou Inst. Glaciol. Geocryology Chinese Academy of Sciences Lanzhou 730000 China Laboratory of Tree-Ring Research University of Arizona Tucson AZ 85721 United States

TREE-ring analysis is one of the important ways for paleoclimatic reconstruction because tree-ring series of several hundred or even thousands of years are available, and can be matched orextended and accurately dated, and the tree rings can record changes in climate. In China,several thousand paleoclimatic series of data are obtained from the historical documents,

关键词： tree-ring chronology paleoclimate Dulan region.

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Density inhomogeneity of upper mantle in Central Asian region

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Chinese Science Bulletin 1997年第12期42卷 1000-1005页

作者： Fang, SM Feng, R Li, CF Sun, GX Tian, CZ Wang, ZL Wang, Y Research Center of Exploration Geophysics State Seismological Bureau Zhcngzhou China Institute of Geophysics State Seismological Bureau Beijing China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China

SINCE International Lithosphere Program was implenented in the early 1980s,the studies of geoscience have focused on the field from oceans to continents.From the 1990s and a futurespan of considerable length the research into continental dynamics will be one of the most ac-tive research fields.There are inhomogeneities in the medium of upper mantle laterally andvertically known from various geophysical investigations.Evidently,density being the

关键词： compensating density of upper mantle geodynamics. Central Asian region.

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Hydrothermal sedimentation and lead-zinc deposit in Dengying formation of the Sinian system in Panxi region

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Chinese Science Bulletin 1999年第S2期44卷 67-68页

作者： ZHU Laiming and RONG Tianjun Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

IN addition to vanadium titano-magnetite, lead-zinc ore is also one of the mineral resources with great exploring potentiality in the Panxi region.of Sichuan Province, China. In the carbonate rock strata of theSinian Dengying Formation which account for about 3.5%-11.4% of the total thickness of the strataexposed in the Panxi region.there are quite a number of the Pb-Zn deposits that account for 53.4% of thetotal Pb-Zn ore reserve in the whole region. Furthermore, some large Pb-Zn deposits such as the Tianbaoshan Pb-Zn deposit in Huili, the Daliangzi Pb-Zn deposit in Huidong and the Yinchanggou Pb-Zn deposit in Ningnan are also hosted in the Sinian Dengying Formation. Why? Previous studies indicated that the high background values of Pb and Zn, favorable lithofacies andpaleogeographic conditions and good ore-hosting structures made the Sinian Dengying Formation a pre-

关键词： hydrothermal sedimentation lead-zinc deposit Dengying formation Panxi region.

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Mean pulse analysis and spectral character study of pulsar PSR B2111+46

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Science China(Physics,Mechanics & Astronomy) 2003年第1期46卷 104-112页

作者： Xu Xuanbin(徐轩彬) Wu Xinji(吴鑫基) Department of Astronomy Peking University Beijing 100871 China Urumqi Astronomy Observation Chinese Academy of Sciences Urumqi 830011 China CAS-PKU Joint Beijing Astrophysics Center Beijing 100871 China Department of Astronomy Peking University Beijing 100871 China Urumqi Astronomy Observation Chinese Academy of Sciences Urumqi 830011 China CAS-PKU Joint Beijing Astrophysics Center Beijing 100871 China

PSR B2111+46 is studied and analyzed by the method of Gaussian fit separation of the average profile (GFSAP). It has been observed at six frequencies,408, 610, 925, 1408, 1640, and 4850 MHz, serving as an excellent sample for a multifrequency analysis. Applying the GFSAP method we find that PSR B2111+46 hasfive components in its profile at all six frequencies. The result supports Rankin's 'core-double cone' model in emission region. On the basis of component decomposition, we discuss the geometrical structure of core, inner cone and outer cone, the emission beam radius, the emission region.altitude and the geometry symmetry. We also examine the spectrum characteristics of core, inner cone and outercone. It is found that the spectrum of the core is steeper than the inner and outer cone.

关键词： pulsars, component decomposition, emission region.

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Monsoon region.: the highest rate of precipitation changesobserved from global data

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Chinese Science Bulletin 1998年第8期43卷 662-666页

作者： Congbin Fu Zhaomei Zheng Chinese Acad Sci Ctr Global Change Res Temperate E Asia Beijing 100029 Peoples R China

The global distributions of the rate of precipitation change at seasonal, interannual and interdecadal scales are computed from the observed global data sets. The analysis has revealed that the monsoon region. in Asia and West Africa, and to lesser extent Australia, have the highest rate of precipitation change at all time scales in the world. These changes are manifested as seasonal jump, high interannual and interdecadal variability and abrupt changes between climate regimes.

关键词： rate of climatic change precipitation monsoon region.

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