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Precise isotopic measurements of sub-nanogram Nd of standard reference material by thermal ionization mass spectrometry using the NdO+ technique

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Precise isotopic measurements of sub-nanogram Nd of standard...

中国科学院地质与地球物理研究所2.07学术年会

作者： Chao-Feng Li~(a,b,c),Fukun Chen~(a,c,*),Xiang-Hui Li~(a,b) a State Key laboratory of Lithospheric Evolution,Institute of Geology and Geophysics,Chinese Academy of sciences,Beijing 10002.,China b {2. of {3. sciences,Graduate university of Chinese Academy of sciences,Beijing 10003.,China c laboratory for Radiogenic Isotope Geochemistry,Institute of Geology and Geophysics,Chinese Academy of sciences,Beijing 10002.,China

The Sm-Nd isotopic system,one of the important techniques for dating and geochemical tracing,has been widely used in *** and accurate measurements of Nd isotopic ratios are more difficult to achieve for microsamples that contain less than 50ng Nd,when routine Nd technique is applied on thermal ionization mass spectrometer(TIMS).Compared to Nd technique,the NdO technique,owing to more efficient ionization,is a better choice for high precision measurements of Nd isotopic ratios of micro- or low-content *** study presents measurement results of sub-nanogram size samples of standard reference solution and rock-powder using NdO technique on the latest TIMS (GV product IsoProbe-T).Sixteen rock-powder references and four reference solutions were measured both by NdO and Nd techniques for an evaluation of accuracy and precision of measurements obtained by the NdO *** show that analytical precision and reproducibility of NdO measurements of sub-nanogram Nd is comparable with those obtained by the Nd measurements of samples containing 2.0 ng *** precision of the Nd/Nd ratios achieved with both techniques is better than 0.003..Our results show that the microsample NdO technique is a very promising method for high resolution Sm-Nd geochronology and isotopic tracing.

关键词： NdO+ technique Chromatography Sub-nanogram sample Isobaric interference

Organic geochemical record of paleocivilization at the Yuchisi Site, Mengcheng, Anhui, China

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Acta Geochimica 2006年第S1期 16-16页

作者： Jianjun WANG1,2. Liguang SUN1, Libin XU1 1 Institute of Polar Environment, school of earth and space sciences, university of {2. and {3. of China, hefei 2.002., China 2.Key laboratory of Global Change and Marine-Atmospheric Chemistry,SOA, Xiamen 3.1005, China

New ternary compound La_8Al_(13.Sn_3

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Rare Metals 2009年第5期28卷 491-493页

作者： HE Wei XIA Xiuwen ZHANG Jiliang HUANG Jinli LIU Yixin Key laboratory of Nonferrous Metal materials and New Processing {2. （Ministry of Education） College of Materials Science and Engineering Guangxi University Nanning 530004 China Department of Physics and Electronic Information science Guangxi Teachers Education University Nanning 530023 China

A new ternary compound La8Al13.n3.was synthesized and studied by means of X-ray powder diffraction technique. The compound La8Al13.n3.crystallizes in a hexagonal AlB2.type structure with space group P6/mmm （No. 191） and the lattice parameters a = 0.44919（1） nm and c = 0.43.3.（1） nm. The Smith and Snyder figure of merit for index, FN, is F3. = 197.3.3.）. The Rietveld refinement for the crystal structure of the compound was carried out successfully. The liability R-factors of Rietveld refinement are Rp = 0.114 and Rwp = 0.148. The compound La8Al13.n3.decomposes into LaAl2.with cubic structure and space group Fd 3. （2.7）, LaAl3.with hexagonal structure and space group P63.mmc （194）, and Sn at 72.°C.

关键词： crystallography X-ray diffraction Reitveld method rare earth compounds

A Resource Recovery Melting Disposal Method for Waste Incineration Residues

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A Resource Recovery Melting Disposal Method for Waste Incine...

2.11 IEEE International Conference on Waste Recycling,Ecology and Environment(ICWREE 2.11)

作者： Zhihong HOU1 * Shiyong LUO2.1 Key laboratory of Testing technology for Manufacturing Process Ministry of Education Mianyang China 2.The laboratory of Printing & Packaging {3. and technology Beijing Institute of Graphic Communication Beijing 102.00 P. R. China

The waste incineration residues included fly ashes and slags, which did not meet the requirements of direct landfill. The waste incineration residues and the mixing powder of carbon-iron-alkali reductant were mixed and then processed as pellets with a diameter of 2.10 mm. The pellets were melted in a electrical furnace at 12.0- 1400℃ and most of pellets had become melt. The cadmium, mercury, and arsenicum in the flue gas would be settled at the bottom of the two water flumes. The lead in the pellets would be reduced as the metal melt, and the chromium solid would settle in the bottom of the electrical furnace. The melt and slag exhausted from the bottom of the electrical furnace were water quenched as raw materials of metallurgy. The melt exhausted from the upper of the electrical furnace were water quenched as the raw materials for building *** such a method, harmful components such as cadmium, arsenicum, lead, mercury, and chromium were removed, and the waste incineration residues were recycled as resources.

关键词： waste incineration residues melting disposal heavy metals

Isolation of cellulase producing microbes from the intestine of Ctenopharyngodon idellus （ Grass Carp） and their cellulase enzymatic activity analysis

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Isolation of cellulase producing microbes from the intestine...

2.05水产科技论坛

作者： WANG Chao-yuan, HAO Bo , HE Li ( College of Life sciences, South Central university for Nationalities, Wuhan, 43.074, China Key {2. of Freshwater Fish Germplasm Resource and Bio{3., CAFS, Jingzhou, Hubei 43.000, China . school of Life science and {3., Huazhong Agriculture university, Wuhan, Hubei 43.074, China)

＜正＞Cellulose is the most abundant and broad organic material on the earth. Because of the lacking of {2., not only the kind of precious resource is not made full use but also most of them are .abandoned and then became one of the pollution of the environment. In order to make full use of cellulose, experiments were carried out to sieve the strain of cellulolytic microbes. 50 bacterial strains were isolated from the enteron of Ctenopharyngodon idellus by an elective medium including sodium carboxymethyl cellulose and 3. strains with some distinct zone of clearing in cellulose medium from the group of strains were obtained. On this basis, with filter paper and absorbent cotton as substrate and the concentration of glucose measured by the colorimetry of DNS, we measured FPase, CMCase and absorbent cotton enzyme activity of liquid culture filtrates. After calculation, we selected 6 strains with high cellu-lase activity. Among them, X2. X4 and X5 showed high FPase producing ability and X3. X5 and X6 showed strong CMCase producing ability. All the 6 strains of microbes were obtained from the middle part and the rear part of the intestine of grass carp. These strains should be stable habitants in the grass carp intestine. Different strains showed different ability to produce cellulase, which may suggest that they collaborate with each other in the grass carp intestine to digest cellulase. Aerobic microbes are the main source of cellulase producing microbes.

关键词： cellulase producing microbes grass carp isolation cellulase activity

Isothermal Crystallization Kinetics of Poly（Ethylene Terephthalate） Modified by Calcium Lignosulfonate

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Isothermal Crystallization Kinetics of Poly（Ethylene Tereph...

2.11 IEEE International Conference on Waste Recycling,Ecology and Environment(ICWREE 2.11)

作者： Hanbing MA1 2. Xiuyun LI 1 2.Li YANG 1 2.Detian LIAO 1 Shaoliang XIE 1 1 State Key {3. Cultivation Base for Nonmetal Composites and Functional materials Mianyang 62.010 China 2.National Insulating material Engineering Research Sub-Center Southwest {3. of science and technology Mianyang 62.010 China

In this study, the effect of Lignosulfonate（LS） skeleton presence on the isothermal crystallization speed of the Poly（ethylene terephthalate）（PET） molecular chains were investigated by using differential scanning calorimetry （DSC）. The isothermal crystallization kinetics of PET and modified PET were analyzed by the Avrami equation. The results indicated that the crystallization rate increased with the addition of LS but decreased with overmuch LS. The Arvami exponent decreasing along with the adding of LS suggested that the crystallization changed from two-dimensional disk-shaped growth to three-dimensional spherulite growth. In addition, the introduction of LS made it less sensitive to the crystallization temperature of the blends.

关键词： Poly(Ethylene Terephthalate) Calcium Lignosulfonate Isothermal Crystallization Crystallization kinetics

PGE patterns of ores of Dajing Cu-polymetallic deposit in Linxi County, Inner Mongolia:Indicator to source of metallogenic elements

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Chinese science Bulletin 2002年第13期47卷 1119-1124页

作者： CHU Xuelei, SUN Min & ZHOU MeifuInstitute of Geology and Geophysics, Chinese Academy of sciences, Beijing 10002., China Key laboratory of Mineral Resources, Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100101, China Department Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Key laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Department of earth sciences The University of Hong Kong Hong Kong China

By comparing PGE patterns of sulfide ores with that of basic-ultrabasic dikes occurring in the Dajing Cu-polymetallic deposit, we discover that there are similar positive slopes between the basic-ultrabasic dikes and the black ores composed mainly of sphalerite and galena, reflecting affinity of their source. The PGE patterns of the yellow ores composed basically of chalcopyrite, arsenopyrite and pyrite are actually different. One is close to the pattern of the mantle 1herzolite, and others resemble the pattern of the basic rocks. However, the concentrations of Ru are higher in the yellow ores, reflecting that sulfur attains or approaches saturation in their parent magma. The PGE characteristics of ores and dikes show that the magmas derived from the deep of crust and the metallogenic elements were supplied mainly by growth material of the crust. In addition, the mantle-derived magma also offered some elements.

关键词： Da Hinggan area polymetallic deposit PGE pattern hypomagma.

MULTISCALE MECHANICAL BEHAVIORS IN DISCRETE materialS: A REVIEW

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Acta Mechanica Solida Sinica 2010年第6期23卷 579-591页

作者： Xiaojing Zheng Dengming Wang (Key laboratory of Mechanics on Western Disaster and Environment,the Ministry of Education of China,Lanzhou university,Lanzhou 73.000,China) Key laboratory of Mechanics on Western Disaster and Environment the Ministry of Education of China Lanzhou University Lanzhou China

The discrete material, which belongs to the category of soft materials, is one of the most prevalent forms of matter in nature and engineering fields. These materials often exhibit abundant and complex mechanical properties which are still far from being perfectly understood. From the view of multi-scale framework concentrated on the ＇bridge＇ role in the macro-micro relation, this review mainly introduces some theoretical investigations of mechanical behaviors in discrete materials, including the continuum constitutive model based on the macroscopic phenomenological approach and coupled micro-macro approach, the statistical analysis of some microscopic physical quantities involved contacted forces between particles and its transmission within the whole system, and the statistical analysis for some microscopic processes in aeolian landform systems involving the grain-bed impact, the transportation and sedimentation of wind-blown sand flux, et al. Finally, some further worthwhile challenges in these fields are suggested.

关键词： discrete material multiple space and time scales trans-scales correlation sanddune statistical analysis

基于归一化互相关成像条件的GPR逆时偏移成像

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中南大学学报（自然科学版） 2018年第5期49卷 1221-1227页

作者：陈德鹏戴前伟冯德山王洪华张彬中南大学地球科学与信息物理学院湖南长沙410083 有色金属成矿预测与地质环境监测教育部重点实验室湖南长沙410083 桂林理工大学地球科学学院广西桂林541004

针对基于零时刻成像条件的探地雷达(GPR)逆时偏移精度低、难以对复杂结构进行高精度成像的缺点,将归一化互相关成像条件应用于GPR叠前逆时偏移成像。从二维GPR电磁波方程出发,采用基于完全匹配层(PML)边界条件的时域有限单元法(FETD)模... 详细信息

针对基于零时刻成像条件的探地雷达(GPR)逆时偏移精度低、难以对复杂结构进行高精度成像的缺点,将归一化互相关成像条件应用于GPR叠前逆时偏移成像。从二维GPR电磁波方程出发,采用基于完全匹配层(PML)边界条件的时域有限单元法(FETD)模拟电磁波正向和逆向传播,采用归一化互相关成像条件获取叠前逆时偏移的偏移结果,将空间高通滤波用于压制互相关过程中产生的低频噪声,然后编制相应的GPR叠前逆时偏移程序。在此基础上,建立2.复杂的GPR模型,利用基于归一化互相关成像条件的GPR逆时偏移程序进行计算,并与基于零时刻成像条件的GPR逆时偏移剖面进行对比。研究结果表明:与基于零时刻成像条件的GPR逆时偏移剖面相比,基于归一化互相关成像条件的GPR叠前逆时偏移剖面能更清晰地反映异常体空间形态和内部结构信息,其分辨率和成像精度更高。

关键词：探地雷达逆时偏移归一化互相关成像条件零时刻成像条件