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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, wuhan 4.0074. china 4. faculty of material sciences and chemical Engineering, china university of geosciences, wuhan 4.0074. 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 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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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 1faculty of Earth science,china university of geosciences,{4. 4.0074.china 2state Key Laboratory of geological Processes and Mineral Resources,china university of geosciences,{4. 4.0074.china 3 Graduate school,china university of geosciences,{4. 4.0074.china 4.Biogeological and Environmental geology Laboratory of Ministry of Education(china university of geosciences) ,{4. 4.0074.china 5 sino-Hungary Joint Laboratory of Environmental sciences and Health,china university of geosciences,{4. 4.0074.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 showδ53Cr 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'sδ53Cr 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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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 Engineering, china {4. of geosciences, wuhan 4.0074. china 2 faculty of materials science and Engineering, Hubei {4., wuhan 4.0062, china 1. faculty of material science and chemical Engineering 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 200-300 nm in length and 30-50 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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Effect of Cooling Rate on Morphology and Oxygen Permeability of Polypropylene

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International Journal of Minerals,Metallurgy and materials 1999年第3期13卷 219-223页

作者： Wei Tian Raymond T. Whodhams(material science and Engineering school, university of science and Technology Beijing, Beijing 100083, china)(Department of chemical Engineering and Applied Chemistry university of Toronto, Toronto M5s IA4. Canada) material science and Engineering school University of Science and Technology Beijing Beijing 100083 China Department of chemical Engineering and Applied Chemistry University of Toronto Toronto Ont. M5S IA4 Canada

The influence of different cooling rates on the morphology and oxygen permeabilityr of polypropylene containing ferrocene has been investigated. The spherulitic crystalline size and structure, which can affect the oxygen permeability are dependent upon the heating temperature, annealing time and cooling rate. The modulus of the composite was measured b}' dynamic mechanical analysis.

关键词： polypropylene oxygen permeability cooling rate

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Oxygen Permeability of Polypropylene Containing Polyisobutene with Magnesium Acetate

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International Journal of Minerals,Metallurgy and materials 2000年第2期14卷 118-121页

作者： Wei Tian Raymond T. Woodhams(material science and Engineering school, university of science and Technology Beijing, Beijing 100083, china)(Dept. of chemical Engineering and Applied Chemistry, university of Toronto, Torono M5s IA4. Canada) Univ sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Univ Toronto Dept Chem Engn & Appl Chem Toronto ON M5S 1A4 Canada

The oxygen permeabilities of polypropylene films are reduced by adding a minor percentage of a polyisobutene ionomer. The polyisobutene ionomers were prepared by in situ salt exchange of magnesium acetate with maleated polyisobutenes of commercially available low relative molecular mass. The more polar magnesiurn salts aided phase separaion during crystallization from the molten polypropylene mixtusre. scanning electron microscope photographs revealed that the polyisobotene ionomer is largely concentratd in the amorphous regions between the polypropylene spherulites, where the ionomer tends to concentrate during crystallization. The influence of the polyisobutene ionomer on the oxygen permeability of polypropylene was found to be slightly dependent upon the relative molecular mass of the polyisobutene precursor. Under optimum conditions, the oxygen permeability of polypropylene is reduced by 20%with only 1% additive.

关键词： oxygen permeability polypropylene polyisobutene

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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 100037, china 2. Development and Research Center, china geological survey, Beijing 100037, china 3. china university of geosciences, Beijing 100083, china 4. china university of geosciences, wuhan 4.0074. 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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IRC analysis of methanol carbonylation reaction catalyzed by rhodium complex

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science china Chemistry 2004年第1期47卷 41-49页

作者： HAO Maorong, FENG Wenlin, Jl Yongqiang & LEI Mingfaculty of science, Beijing university of chemical Engineering, Beijing 100029, china faculty of chemical Engineering, Ningxia university, Yinchuan 750021, china 1. faculty of science Beijing University of Chemical Engineering 00029 Beijing China 2. faculty of chemical Engineering Ningxia University 750021 Yinchuan China

In the reaction cycle for methanol carbonylation catalyzed by Rh complex, the structure geometries of the reactant, intermediates, transition states and product of each elemental reaction have been studied by using the energy gradient method at HF/LANL2DZ level, and the changes of their potential profiles have also been calculated. Through IRC analyses of the transition states for each elemental reaction, it is confirmed that the various structure geometries obtained are stationary points on the cycle reaction pathway of methanol carbonylation catalyzed by Rh complex, and the changes are given in energies and structure geometries of the reactant molecules along the reaction pathway of lowest energy. It has been proposed that the geometrical conversions of intermediates play an important role during the cycle reaction. Through analyses of structure geometries, it has been suggested that, in addition to cis- and transstructure exchange linkage of catalysis reactive species, the two pathways, cis- and frans-catalyzed cycle reactions, can also be linked through geometrical conversion of intermediates, of which the activation energy is 4..79 kJ/mol. Moreover, the reductive elimination elemental reaction may be neither c/s-cycle nor trans- one, showing that the cycle reaction can be achieved through various pathways. However different the pathway, the oxidative addition elemental reaction of CH3I is the rate-controlling step.

关键词： rhodium complex catalyst, methanol carbonylation, ab initio method, homogeneous catalysis.

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A NOVEL INTERPRETATION OF CONCENTRATION DEPENDENCE OF VIsCOsITY OF DILUTE POLYMER sOLUTION

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Chinese Journal of Polymer science 2000年第1期18卷 57-67页

作者： Yan Pan Rong-shi Cheng College of material science and Engineering, south china university of Technology, Guangzhou 51064., china College of Chemistry and {4. Engineering, Nanjing university, Nanjing 210093, china s china Univ Technol Coll Mat Sci & Engn Guangzhou 510641 Peoples R China Nanjing Univ Coll Chem & Chem Engn Nanjing 210093 Peoples R China

The concentration dependence of the reduced viscosity of dilute polymer solution is interpreted in the light of a new concept of the self-association of polymer chains in dilute solution. The apparent self-association constant is defined as the molar association constant divided by the molar mass of individual polymer chain and is numerically interconvertible with the Huggins coefficient. The molar association constant is directly proportional to the effective hydrodynamic volume of the polymer chain in solution and is irrespective of the chain architecture. The effective hydrodynamic volume accounts for the non-spherical conformation of a short polymer chain in solution and is a product of a shape factor and hydrodynamic volume. The observed enhancement of Huggins coefficient for short chain and branched polymer is satisfactorily interpreted by the concept of self-association. The concept of self-association allows us to predict the existence of a boundary concentration C-s(dynamic contact concentration) which divides the dilute polymer solution into two regions.

关键词： self-association polymer solution viscosity concentration dependence

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Effect of yttrium on the microstructure of a semi-solid A356 Al alloy

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Rare Metals 2008年第5期27卷 536-540页

作者： LIUZheng HU Yongmei faculty of material and chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 China

The semi-solid slurry of an A356 Al alloy, which was grain-fined by yttrium, was manufactured by low temperature pouring, The effects of grain-refining on the morphology and the grain size of the primary α phase in the semi-solid A356 Al alloy were researched. The results indicate that the semi-solid A356 AI alloy with particle-like and rosette-like primary α-Al can be prepared by low temperature pouring from a liquid grain-refined A356 alloy. The grain size and particle morphology of primary α-Al in the A356 Al alloy are markedly improved by the addition of 0.5 wt,% Y. The fining mechanism of Y on the morphology and grain size of the primary α-Al in the semi-solid A356 Al alloy was delved.

关键词： A356 Al alloy semi-solid yttrium low temperature pouring

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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. faculty of {4. science and chemical Engineering, china university of geosciences, wuhan 4.0074. china 1. Dalian Institute of chemical Physics Chinese Academy of Sciences Dalian 116011 China 3. faculty of material science and chemical Engineering 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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