检索结果-南通市图书馆

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. 4.0074. china 4. faculty of material sciences and chemical engineering, china university of geosciences, {4. 4.0074. 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 {4. 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.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Synthesis and photochromic properties of WO_3 powder induced by oxalic acid

引用

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,{4., wuhan 4.0074. china 2 faculty of materials Science and engineering, Hubei university, wuhan 4.0062, china faculty of material Science and chemical engineering China University of Geosciences Wuhan China faculty of materials Science and engineering 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 200-300 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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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 4.0074. 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-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/WH3BO3=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) (396 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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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, wuhan 4.0074

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.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Research into Exploitation and Application of Three Sorts of

引用

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 engineering,{4., wuhan 4.0074

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.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Weathered Mantle Hosted Gold Deposit atShewushan, Hubei, Central china

引用

Journal of china university of geosciences 2001年第1期12卷 60-67页

作者： Hong Hanlie Wang Qinyan The Center for material Research and Testing, wuhan university of Technology, wuhan 4.0070 Bian Qiujuan {4. of Earth sciences, china university of geosciences, wuhan 4.0074 The Center for material Research and Testing Wuhan University of Technology faculty of Earth sciences China University of Geosciences

A supergene gold deposit is located at Shewushan, south Hubei, Central china. The Au mass fraction of the supergene deposits ranges from 1.0.10-6 to 19.5 10-6, with an average of about 2.2 10-6. Primary gold mineralization is closely associated with the well developed faults and fractures mainly on the crest of the reverse anticline with gold mass fraction exceeding1.0 X 10-6(average 0.6 X 10-6 ), the gold occurs as small Ag-bearing particles in association with illite and kaolinite, and partly incorporated within the lattice of pyrite. Fluid inclusion studies on the gold mineralization yield trapping temperatures and pressures from 110 to 290 and 4.0 105 to 4.0 105 pa, respectively. The salinities of mineralization fluids range from 2. 6 % to 8. 4.% w(NaCl, equivalent). Calculated (18O) values and measured (D) data of the hypogene fluids indicate a meteoric origin. These fluids underwent extreme 18 O enrichment by reacting with country carbonate rock. Supergene gold minerali- zation is confined largely to the lower portion at the weathered mantle; the gold occurs as small native gold particles accompanied by clay minerals, kaolinite and illite and Mn and Fe oxides. Geochemical investigation shows that Au, together with As and Sb, decreases progressively from the top of ore body to some 2 kilometers away and define a lateral dispersion halo. It is proposed that the gold is mobilized by surficial leaching and concentrated at the lower portion of the weathering profile, and thio-sulfate may play an active role in gold dissolution and re-precipitation.

关键词： gold deposit weathering inclusion temperature stable isotopes Shewushan.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

On-line parallel reversed phase two-dimensional liquid chromatography for high-throughput analysis of complex proteomic samples

引用

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 4.0074. china Dalian Institute of chemical Physics Chinese Academy of Sciences Dalian China faculty of material Science and chemical 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.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Mass and Energy Transportation in Ore-Forming Processes of Sulfide Deposits in Tongling District

引用

Journal of Earth Science 1999年第4期18卷 299-304页

作者： Cen Kuang Yu Chongwen(faculty of Earth sciences, china university of geosciences, wuhan 4.0074. faculty of Earth sciences China University of GeosciencesWuhan 430074

Based on dynamics of heat conduction, fluid flow caused by heating and chemical material transport induced by fluid flow, temperature and stream fields of fluid flow in ore-forming processes of Cu-Au sulfide in the Tongling district deposits was modeled and analyzed. It is shown that: (1) Mass and energy flow caused by fluid flow is key problem of kythrothermal ore-forming processes; the heating from magma intruded is basic power for driving fluid flow. (2) occurrence of pluton, different chemical property and porosity of wall rocks and infiltration restrict the specifically field of precipitation for ore-forming ***, the dissolution and precipitation field for ore-forming material in deposit can be forecasted. (3) Iron and sulfur material comes mostly from sandstone formation of Wutong Group, which contains pyrite and high porosity. The cataclastic dolomite interlayered in sandstone and limestone is a favorable place for ore accumulating. The difference of chemical property between sandstone and dolomite forms a favorable interface for ore-forming processes.

关键词： heat conduction mass transportation fluid path-line streamline

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：