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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 4.0007, china 3. State Key Laboratory of Geological Processes and Mineral Resources at china university of geosciences,{4., china 4. faculty of material sciences and chemical engineering, china university of geosciences,{4., china 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

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 13. background values are intensively controlled by palaeogeographic environment. In general, δ 13. 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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On-line parallel reversed phase two-dimensional liquid chromatography for high-throughput analysis of complex proteomic samples

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Science china Chemistry 2006年第6期49卷 527-533页

作者： WANG Zhicong1,3. ZHANG Qinghe2, LI Tong2, ZHAO Zhongyi3.& ZHANG Weibing1 1. Dalian Institute of chemical Physics, Chinese Academy of sciences, Dalian 116011, china 2. Dalian Elite Analytical Instrument Co., Ltd., Dalian 116011, china 3. {4. of material Science and chemical engineering, china university of geosciences, wuhan 43.074, china 1. Dalian Institute of chemical Physics Chinese Academy of Sciences Dalian 116011 China 3. faculty of material Science and chemical{3. China University of Geosciences Wuhan 430074 China 2. Dalian Elite Analytical Instrument Co. Ltd. Dalian 116011 China

A comprehensive two-dimensional liquid chromatographic system (2D SCX/RP) is con- structed with a 10-port-2-way valve using strong cation exchange chromatography (Hypersil SCX, 100 mm×4.6 mm I.D.) followed by reversed phase chromatography (Hypersil BDS C18, 15 mm×4.6 mm I.D.) to separate the complex peptides from globin peptic hydrolysate. After the sample was loaded on the SCX column, the phosphate buffer (pH 4.0) was used to elute the peptides. Then, elutes flowed through the interface and the peptides focused on the head of the trapping columns (Hypersil BDS C18, 15 mm×4.6 mm I.D.) but salt passed into the waste. After the valve was switched, the samples were flushed with a backward flow into the RP analytical column. The peptides on the SCX were eluted with 12 discontinuous steps linearly increasing salt concentrations. The peptides enriched on the trapping column were desalted and separated by the RP columns. The resolution and the resolved peaks of the 2D SCX/RP system were greatly increased and the total peak capacity reached as high as 2280.

关键词： two-dimensional liquid chromatography, interface, trapping column, proteomics, globin.

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Synthesis and photochromic properties of WO_3.powder induced by oxalic acid

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Science china Chemistry 2009年第5期52卷 609-614页

作者： SHEN Yi1, ZHU Hua1, HUANG Rong1, ZHAO Li2 & YAN ShaNing1 1 faculty of material Science and chemical{3.,{4., wuhan 43.074, china 2 faculty of materials Science and{3., Hubei university, wuhan 4.0062, china 1. faculty of material Science and chemical{3. China University of Geosciences Wuhan 430074 China 2. faculty of materials Science and engineering Hubei University Wuhan 430062 China

Tungsten trioxide powder with the novel morphology was prepared via the hydrothermal method with oxalic acid as the organic inducer, the structure and shape of which were detected by X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET. Furthermore, photochromic properties of the as-prepared powder samples were tested by an ultraviolet-visible spectrophotometer combined with a color difference meter. The corresponding results indicated that the induced product was still hexagonal WO3. made up of regularly spindle particles with 200-3.0 nm in length and 3.-50 nm in width. The ratio of the length and width was from 4.to 10. Moreover, the special morphology improved its absorptive capacity to the excitation light source, resulting in its high photochromic properties.

关键词： WO3 powder photochromism oxalic acid organic inducer

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Analytical method of Cr stable isotope and its application to water pollution survey

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Chinese Science Bulletin 2010年第7期55卷 664-669页

作者： GAO YongJuan 1,2,3.MA Teng 4.5,LING WenLi 1,2,LIU CunFu 4.5 & LI Li 4.5 1{3. of Earth Science,china university of {3.,{4. 43.074,china 2State Key Laboratory of Geological Processes and Mineral Resources,china university of {3.,{4. 43.074,china 3.Graduate School,china university of {3.,{4. 43.074,china 4.Biogeological and Environmental Geology Laboratory of Ministry of Education(china university of {3.) ,{4. 43.074,china 5 Sino-Hungary Joint Laboratory of Environmental sciences and Health,china university of {3.,{4. 43.074,china faculty of Earth Science China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China Graduate School China University of Geosciences Wuhan 430074 China Biogeological and Environmental Geology Laboratory of Ministry of Education (china university of geosciences) Wuhan 430074 China Sino-Hungary Joint Laboratory of Environmental sciences and Health China University of Geosciences Wuhan 430074 China

High Cr(VI) concentration is a potential serious risk to environment and ecologic ***,it is essential to effectively monitor Cr contamination in water systems and scientifically evaluate its evolution trend.A new method of in-situ tracer technique by Cr isotopic analysis for quantitatively estimating Cr-contamination and its regional evolution in natural waters as well as a case application are reported in this *** on documented literatures,an experimental procedure for chemical separation and purification of Cr in water samples and its analytical method for Cr isotopic measurement by thermal ionization mass spectrometry(TIMS) are *** samples collected around a chemical factory in Hubei Province were analyzed by this *** samples showδ53.r values ranging from-1.7‰to 7.3.and an elevating trend with an increasing in distance from the sampling site to pollution source.A functional correlation following Rayleigh fractionation law was established between sample'sδ53.r value and its extent of Cr *** study suggests that Cr isotopic analysis is an effective method to reveal the spatial distribution and its evolution trend of Cr contamination in the regional water *** is thus helpful to assessing the self-purifying ability of local water system according to Cr isotopic fractionation.

关键词：铬(VI) 水污染调查稳定同位素应用同位素分析供水系统演变趋势示踪技术

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Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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Science china Earth sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2, XU Ran1, TANG Zhongdao1, SI Yuanlan3.& LI Baohua4.1. faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources, china university of geosciences,{3., {3. 2. Institute of Resources & Environments, Henan Polytechnic {4., Jiaozuo 4.4.03. {3. 3. Department of Computer Science, South-Central {4. for Nationalities,{3., {3. 4. Laboratory of Marine Geology, Tongji {4., Shanghai 200092, {3. faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources china university of geosciences wuhan{3. Institute of Resources & Environments Henan Polytechnic university Jiaozuo china Department of Computer Science South-Central university for Nationalities wuhan china Laboratory of Marine Geology Tongji university Shanghai china

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13.carb and δ 13.kerogen) from +0.4. (‰ V-PDB) to +3.54.(‰ V-PDB) and from ?29.3. (‰ V-PDB) to ?24.14.(‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3.X 15%)) values from 0.015 to 0.14., TOC values from 0.02% to 0.21%, V/Cr values from 0.3.to 2.0, Sr/Ba values from 3.20 to 4..50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South china, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2, climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South china.

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Synthesis and photoluminescence property of red phosphors LiEu_(1-x)Y_x(WO_4._(0.5)(MoO_4._(1.5) for white LED

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Science china(Technological sciences) 2009年第7期52卷 1913-1918页

作者： XIE An, YUAN XiMing, WANG JuanJuan & WANG Feng engineering Research Center of Nano-Mineral materials and Application, Ministry of Education, faculty of materials Science and {4. engineering, china university of geosciences, wuhan 43.074, china 1. engineering Research Center of Nano-Mineral materials and Application Ministry of Education Faculty of Materials Science and Chemical Engineering China University of Geosciences Wuhan 430074 China

A series of novel red phosphors LiEu1-xYx(WO4.0.5(MoO4.1.5 (x=0, 0.1, 0.2, 0.3. 0.4. 0.5, 0.6, 0.8) were synthesized by conventional solid state reaction method with the starting {3.s: WO3. MoO3. Eu2O3. Li2CO3.and Y2O3. The spectrum and the crystal structure of the phosphors were characterized by F-4.00 and XRD respectively. Meanwhile the effects of flux and Y3. concentration on the crystal structure and luminescent properties of the phosphors were investigated. The results showed that the optimal content of flux (WAlF3.WH3.O3.1/1) was 1 wt% and the optimal doping concentration of Y3. was 0.5 mol. The emission spectrum showed the most intense peak was located at 615 nm, which corresponds to the 5D0→7F2 transition of Eu3. and that Eu3. occupied the lattice site of noncentrosymmetric environment in the scheelite phases. The excitation spectrum displayed that these phosphors could be effectively excited by ultraviolet (UV) (3.6 nm) and blue (4.6 nm) light, nicely in correspondence with the widely ap- plied output wavelengths of ultraviolet or blue LED chips. The influence of flux on the luminescent properties of LiEu0.5Y0.5(WO4.0.5(MoO4.1.5 phosphor was analyzed. The XRD spectra indicated that the flux could help to crystallize the phosphor, and no other phases were formed except the tetragonal. When adding flux, the relative intensity of LiEu0.5Y0.5(WO4.0.5(MoO4.1.5 became much stronger and the average particle size of the phosphor decreased.

关键词： red emitting phosphor LiEu1-xYx(WO4.0.5(MoO4.1.5 flux white LED

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Complexity and Self-Organized Criticality of Solid Earth System(Ⅰ)

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Journal of Earth Science 1998年第1期17卷 30-47页

作者： Yu Chongwen faculty of Earth sciences, china university of geosciences,{3.

The author puts forward the proposition of Complexity and Self Organized Criticality of Solid Earth System in the light of: (1) the science of complexity studies the mechanisms of emergence of complexity and is the science of the 21st century, (2) the study of complexity of the earth system would be one of the growing points occupying a strategic position in the development of geosciences in the 21st century. By the proposition we try to cogitate from a new viewpoint the ancient yet ever new solid earth system. The author abstracts the fundamental problem of the solid earth system from the essence of the generalized geological systems and processes which reads: the complexity and self organized criticality of the global nature, structure and dynamical behavior of the whole solid earth system emerging from the multiple coupling and superposition of non linear interactions among the multicomponents of the earths material and the multiple generalized geological (geological, geophysical, and geochemical) processes . Starting from this cognizance the author proposes eight major themes and the methodology of researches on the complexity and self organized criticality of the solid earth system.

关键词： complexity self organization self organized criticality the solid earth system fractal chaos long range spatio temporal correlation fractal spatio temporal structure.

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Surface roughness and removal rate in magnetorheological finishing of a subsurface damage free surface

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Progress in Natural Science:materials International 2005年第6期15卷 538-544页

作者： CHENG Haobo1*, WANG Yingwei2, FENG Zhijing1 and CHENG Kai3.1. State Key Laboratory of Tribiology, Tsinghua university, Beijing 100084. china 2. Department of {3. {3., Changchun university of Science and Technology, Changchun 13.021, china 3. faculty of Information and engineering Systems, City Campus, Leeds LS1 3.E, UK) State Key Laboratory of Tribiology Tsinghua University Beijing 100084 China Department of material sciences Changchun University of Science and Technology Changchun 130021 China faculty of Information and engineering Systems City Campus Leeds LS1 3HE UK

Based on computer-controlled optical surfacing, a new technique called magnetorheological finishing (MRF), is presented. The new technique combines the features of conventional loose abrasive machining with a wheel shaped polishing tool. The tool incorporates a host of features and has unprecedented fabricating versatility. The pre-polishing and fine polishing processes can be performed only by adjusting different parameters. The material removal function is studied theoretically and the results of simulation present a Gaussian distribution feature. Based on the established theoretical model, material removal rate experiments involving a parabolic mirror are designed and carried out to determine the effect of controllable parameters on size of the gap between the workpiece and the polishing wheel, rotating speed of the polishing wheel, concentration of volume fraction of non-magnetic particles and polishing time. Further experiments are carried out on the surface microstructure of the workpiece, the final surface roughness with an initial value of 10.98 nm reaches 1.22 nm root mean square (RMS) after 20 min of polishing. The subsurface damage experiment and the atomic force microscopy (AFM) measurement on the polished surface can also verify the feasibility of the MRF technique.

关键词： magnetorheological finishing surface roughness computer controlled optical surfacing subsurface damage removal function.

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Lithosphere types in North china:Evidence from geology and geophysics

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Science china Earth sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2, DENG Jinfu3. ZHOU Su3. LI Jinfa4. XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3.1. Institute of Geology, Chinese Academy of Geological sciences, Beijing 10003., china 2. Development and Research Center, china Geological Survey, Beijing 10003., china 3.{4., Beijing 100083. china 4.{4., wuhan 43.074, china 5. Information Center of Ministry of Land and Resources, Beijing 100812, china 6. Institute of Geology, State Seismological Bureau, Beijing 100029, china 1. Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China 2. Development and Research Center China Geological Survey 100037 Beijing China 3. china university of geosciences 100083 Beijing China 4. china university of geosciences 430074 Wuhan China 5. Information Center of Ministry of Land and Resources 100812 Beijing China 6. Institute of Geology State Seismological Bureau 100029 Beijing China

On the basis of the characteristics of geology and geophysics in North china, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North china platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North china Platform is a remnant of cratonic lithosphere after the North china platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North china in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

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Research into Exploitation and Application of Three Sorts of

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Journal of Earth Science 2000年第2期19卷 96-97页

作者： Li Zhen Shen Shangyue Chi bo Zhang De Yang Mei faculty of material sciences and Chemistry{3.,{4., wuhan 43.074

In this paper the authors introduce their past years’study results about the exploitation and application of three sorts of nontraditional nonmetal minerals. In this research, the main aspects and techniques of basic study for the exploitation and application are summarized, and some key science and technological problems are proposed as the objects of their future research.

关键词： nontraditional nonmetal minerals exploitation application medified superfine papermaking plastic rubber.

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