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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 material science and chemical engineering, china university of geosciences, wuhan 430074, china Dalian Institute of chemical Physics Chinese Academy of Sciences Dalian China faculty of material science and {3. engineering China University of Geosciences Wuhan China Dalian Elite Analytical Instrument Co. Ltd. Dalian 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.

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 {3. engineering, china university of geosciences, wuhan 430074, china 2 faculty of materials science and engineering, Hubei university, {13. 43.062, china faculty of material science and {3. engineering China University of Geosciences Wuhan China faculty of materials science and {3. Hubei University Wuhan 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

Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South china

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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{3., wuhan 430074, china 4. faculty of material sciences and chemical engineering,{3., 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 {3. 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 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.

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 chemical engineering, china university of geosciences, wuhan 430074, china engineering Research Center of Nano-Mineral materials and Application Ministry of Education Faculty of Materials Science and Chemical Engineering China University of Geosciences

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 materials: WO3. MoO3. Eu2O3. Li2CO3.and Y2O3. The spectrum and the crystal structure of the phosphors were characterized by F-4500 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 (466 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

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 {3. of geosciences,wuhan 430074,china 2State Key Laboratory of Geological Processes and Mineral Resources,china {3. of geosciences,wuhan 430074,china 3.Graduate School,china {3. of geosciences,wuhan 430074,china 4 Biogeological and Environmental Geology Laboratory of Ministry of Education(china {3. of geosciences) ,wuhan 430074,china 5 Sino-Hungary Joint Laboratory of Environmental sciences and Health,china {3. of geosciences,wuhan 430074,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

Evolution Mechanism of Slip Zone Under Fluctuation of Ground Water Table of Landslide

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地学前缘 2009年第S1期16卷 55-56页

作者： Bo Chai~1,Kunlong Yin~2 1.School of Environmental Studies,china university of geosciences({3.),{3. 430074,china. 2.engineering faculty,china university of geosciences({3.),{3. 430074,china

The fluctuation of ground water table of landslide caused by the changing of rain fall and reservoir water level leads the slip zone to possess the complicated deformation features of stepped and *** role of the groun... 详细信息

关键词： groundwater fluctuation slip zone landslide

Electrocatalytic Activity of Tungsten Trioxide Microspheres, Tungsten Carbide Microspheres and Multi-walled Carbon Nanotube-tungsten Carbide Composites

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Journal of wuhan university of Technology(materials {3.) 2009年第2期24卷 229-234页

作者：陆洪智 faculty of engineering China University of Geosciences

Tungsten trioxide micropheres were prepared by spray pyrolysis, and tungsten carbide microspheres were produced by spray pyrolysis-low temperature reduction and carbonization technology. Multi-walled carbon nanotube-tungsten carbide composites were prepared by the continuous reduction and carbonization process using multi-walled carbon nanotubes （MWCNTs） and WO3.precursor by mo- lecular level mixing and calcination. The morphology and structure of the samples were characterized by scanning electron microscope and transmission electron microscope. Furthermore, the crystal phase was identified by X-ray diffraction. The electrocatalytic activity of the sample was analyzed by means of me- thanol oxidation. Tungsten carbide microspheres were catalytic active for methanol oxidation reaction. Nevertheless tungsten trioxide microspheres and multi-walled carbon nanotube-tungsten carbide composites were not catalytic active for methanol oxidation reaction. These results indicate that tungsten carbide micropheres are promising catalyst for methanol oxidation.

关键词： nanostrucmres chemical synthesis chemical techniques WO3 WC-MWCNT composites

Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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science china(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2, LIU GuoQuan2, LI ZhiLin3. FENG ChengMing1 1 Mechanical and Electronic engineering College, Shandong Agricultural university, Tai’an 271018, china 2 College of {3.s science and engineering, university of science and Technology, Beijing 100083. china 3.College of {3. science and engineering, Beijing university of {13. Technology, Beijing 100029, china Mechanical and Electronic engineering College Shandong Agricultural UniversityTai'an 271018China College of materials science and engineering University of Science and TechnologyBeijing 100083China College of material science and engineering Beij

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements

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., china 2. Institute of Resources & Environments, Henan Polytechnic university, Jiaozuo 454003. china 3. Department of Computer science, South-Central university for Nationalities,{3., china 4. Laboratory of Marine Geology, Tongji university, Shanghai 200092, china china university of geosciences Henan Polytechnic university South-Central university for Nationalities Tongji university

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13.carb and δ 13.kerogen) from +0.43.(‰ 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 0.144, TOC values from 0.02% to 0.21%, V/Cr values from 0.3.to 2.0, Sr/Ba values from 3.20 to 49.50 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.

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 {3. engineering, Beijing 100029, china faculty of {3. engineering, Ningxia university, Yinchuan 750021, china faculty of science Beijing University of Chemical Engineering Beijing China faculty of chemical engineering Ningxia University 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 49.79 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 CH3. is the rate-controlling step.

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