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Study on Microbes and Their Effects on Rare earth Extraction in Weathering Crust of Granite

Journal of Rare earths 2001年第3期19卷 161-167页

作者：陈炳辉毋福海刘琥琥 dept. of earth sci. Zhongshan Univ. Guangzhou 510275 China

Microbes were cultured from the samples at various dept.s in a weathering profile of RE-bearing granite in Gonghe RE mine, Guangdong Province. The cultured microbes, existing at a dept. of 0.2 similar to 12 in and being more plentiful within 3 in in the profile, include bacteria ( Bacillus, Enterobacter, Escherichia, Alkaligenes, Neisseria, Staphylococcus and anaerobic bacteria such as Clostridium), fungi ( Aspergillus niger, Aspergillus flavus, Penicillium, Mucor and Saccharomycete) and actinomyces. Experiments were made under room temperature by using solutions of the cultured microbes and their metabolites, compared with distilled water and the culture solution without microbes, to leach RE from the sample of the weathering crust. The results are shown by the experiments: (1) The mixed microbes cultured from the profile and their metabolites increase the quantity of RE leached from the sample and reduce the pH of the solutions. (2) The ability to leach RE from the sample varies with various microbes, decreasing in a sequence of fungi ( Mucor, saccharomycete, Aspegillus and Penicillium), zymotic bacilli (Enterobacter, Escherichia etc.), Staphylococcus, zymotic Bacillus, actinomyces and Alkaligenes. (3) The RE leached with bacteria is mainly related to the pH value of the solutions influenced by the metabolites of the bacteria; whereas that leached with fungi is mainly related to the adsorption and imbibition of RE by the fungi and the complexing of RE with their metabolites. (4) Compared with that leached with ammonium sulfate, the fractionation of the RE leached with microbes is characterized by higher delta (Ce), lower delta (Eu) and lower ratios of N-La/Sm and N-Gd/Yb . The result of the fractionation of RE accords with the distribution of RE in the various layers of a profile of weathering crust of granite in South China. The experimental results indicate that microbes and their metabolites should play a positive role in the mobilization, migration and fractio

关键词： rare earths microbes weathering crust granite

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A new Early Cretaceous lizard with well-preserved scale impressions from western Liaoning, China

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Progress in Natural sci.nce:Materials International 2005年第2期15卷 67-73页

作者： JI Shu’an*(School of earth and space sci.nces, Peking University, Beijing 100871, China) Sch. of earth and space sci. Peking Univ. Beijing 100871 China

A new small lizard, Liaoningolacerta brevirostra gen. et sp. nov., from the Early Cretaceous Yixian Formation of western Liaoning is described in detail. The new specimen was preserved not only by the skeleton, but also by the exceptionally clear scale impressions. This lizard can be included within the taxon Scleroglossa based on its 26 or more presacrals, cruciform interclavicle with a large anterior process, moderately elongated pubis, and slightly notched distal end of tibia. The scales vary evidently in size and shape at different parts of body: small and rhomboid ventral scales, tiny and round limb scales, and large and longitudinally rectangular caudal scales that constitute the caudal whorls. This new finding provides us with more information on the lepidosis of the Mesozoic lizards.

关键词： new genus Squamata skeleton lepidosis Early Cretaceous western Liaoning

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A new method for preparing ultrafine powders-- Precipitation transformation method

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Chinese sci.nce Bulletin 1996年第9期41卷 736-739页

作者：周根陶刘双怀郑永飞 dept. of earth and space sci.nces Univ. of Sci. and Technol. of China Hefei 230026 China Department of Applied Chemistry Univ. of Sci. Technology of China Hefei 230026 China

The particle sizes of ultrafine powders are between cluster and fine powders, with theparticle diameters generally in the range of 1--100nm. When compared with commonmaterials consisting of bigger particles, materials consisting of nanometer-size particleshave many special properties. These include small-sized effect, surface and interface

关键词： precipitation transformation method ultrafine powders copper (Ⅱ) oxide nickel hydroxide nickel oxide.

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Distribution, Transportation and Cytolocalization of Neodymium in Oilseed Rape (Brassica napus L.)

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Journal of Rare earths 2001年第2期19卷 157-160页

作者：魏幼璋 dept. of Soil sci. and Agrochemistry Zhejiang Univ. Hangzhou 310029 China

Observation xith the transmission electronic microscopy shows that Nd can not enter into the cytoplasm of oilseed rape (brassica napus L.) in solution culture. It combines with the cell wall or amasses in the intercellular space. Nd accumulates in root tip after it enters into the plants, while only a small amount of Nd is transferred to the stem and leaf via apoplasm, and the leaf contains the least of Nd. Such observations are consistent with the analytical results of Nd distribution in rape tissues in soil culture experiment. It suggests that the physiological effects of Nd in plants might mainly function on plasmalemma of root system.

关键词： Biology Transmission electron microscopy Transportation

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Studies on Intermolecular Energy Transfer and Relaxation Processes in Solid Rare earth Complexes by Photoacoustic Spectroscopy

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Journal of Rare earths 2001年第3期19卷 181-186页

作者：伍荣护赵化章于锡娟宋慧宇苏庆德 dept. of Chem. Univ. of Sci. and Technol. of China Hefei 230026 China

The photoacoustic spectra of Eu ( benz)(3) (.) ( phen)(2) ( benz: benzoate, phen: phenanthroline) and Eu-0.(8)Ln(0.2)(benz)(3)(.)(phen)(2)(Ln(3+) : La3+ or Nd3+) were reported. The intermolecular energy transfer processes were studied from the point of the nonradiative transitions. Combined with the fluorescence spectroscopy, photoacoustic spectroscopy reflects the variation of the luminescence efficiencies of solid samples. The luminescence efficiency increases when La3+ is introduced, but it decreases greatly when Nd3+ is added, which is due to the difference of intermolecular energy transfer processes. The models of intramolecular and intermolecular energy transfer and relaxation processes were established.

关键词： rare earths photoacoustic spectroscopy solid complexes variation of luminescence efficiencies intermolecular energy transfer

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Study on Anticoagulation Factor I from Agkistrodon Acutus Venom by Rare earth Ion Probes

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Journal of Rare earths 2002年第4期20卷 302-307页

作者：徐小龙刘清亮解永树 dept. of Chem. Univ. of Sci. and Technol. of China Hefei 230026 China

It was observed that rare earth ions (Nd 3+, Sm 3+, Eu 3+, Gd 3+, Tb 3+) have significant quenching effects on the fluorescence of anticoagulation factor I (ACF I). The results of the fluorescence titration of ACF I with rare earth ions demonstrate that ACF I has two RE 3+-binding sites, and the rare earth ions and Ca 2+ bind to ACF I competitively in the two similar sites. The association constants K 1 and K 2 of ACF I with each rare earth ions (Nd 3+, Sm 3+, Eu 3+, Gd 3+, Tb 3+) are close to each other, which indicates the structural similarity of the two binding sites in ACF I. Although the ionic radii of Nd 3+, Sm 3+, Eu 3+, Gd 3+ and Tb 3+ are different, both their K 1 and K 2 are similar, respectively. This reveals the conformational flexibility of the two binding sites in ACF I, which offers a possibility for Ca 2+ to take play in the inducing conformational changes of ACF I and the promoting the binding of ACF I with activated coagulation factor X.

关键词： rare earths anticoagulation factor I fluorescence probe metal ion binding-site

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Carbon isotope anomaly in marbles associated with eclogites from the Dabie Mountains

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Chinese sci.nce Bulletin 1998年第2期43卷 155-160页

作者： Yongfei Zheng Bin Fu Bing Gong Yilin Xiao Yiliang Li Univ sci.& Technol China Dept Earth & Space Sci Hefei 230026 Peoples R China

This is a report of carbon isotope anomaly in marbles associated with the UHP eclogites from the Dabie Mountains. The results place constraints on the degree of crust_mantle interaction during the UHP metamorphism.

关键词： carbon isotopes marble and eclogite UHP metamorphism crust_mantle interaction Dabie Mountains.

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Affinities and functional morphology of the Middle Cambrian ornamented tubules from West Hunan,China

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Progress in Natural sci.nce:Materials International 2004年第10期14卷 67-71页

作者： ZHU Caifa 1,2 and DONG Xiping 1 (1.School of earth and space sci.nces,Peking University,Beijing100871,China 2.University of Petroleum,Beijing102249,China) Sch. of earth and space sci. Peking Univ. Beijing 100871 China Univ. of Petroleum Beijing 102249 China

Problematic phosphatic tubular microfossils with ornamented sculptures are documented to exist in limestones of the up-per Middle Cambrian Huaqiao Formation at the Paibi section and the Wangcun section in West Hunan,*** morphological pat-terns,including Ornamented Tube Form I and Ornamented Tube Form II are *** on the analysis of the preservation,wall structure and composition of the fossils,it is deduced that these ornamented tubes may represent carapace spines of some Cambrian arthro-pods with phosphatic carapaces,such as bradoriid *** of functional morphology indicates that the sclerites may rather be considered of a defensive than grasping function on the original organism body.

关键词： Middle Cambrian ornamented tubes affinities functional morphology West Hunan

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Study of Microstructure and Magnetic Properties of Pr-Fe-B-Cu Permanent Magnets by Hot Deformation

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Journal of Rare earths 2002年第3期20卷 188-192页

作者：陈秀云姜忠良高天明吴严杨昌平朱静 dept. of Mater. sci. and Eng. Sch. of Mater. Sci. and Eng. Tsinghua Univ. Beijing 100084 China

The relationship between the microstructures and magnetic properties of rare earth cast permanent Pr Fe B Cu alloys by hot deformation was studied. Fine and well aligned column grains can be obtained by using a proper solidification mould with a high cooling rate. The soft magnetic phase α Fe can be removed during proper annealing treatment. Hot pressing can produce the anisotropy and refine the grain size, so that the magnetic properties are greatly improved. The technique has the advantages of simple processing, low cost and high benefit, compared with the common sintering processing. Under the condition of the deformation temperature of 1073 K, 90% strain and strain rate of 40×10 -3 s -1 , the magnetic properties obtained are: B r=1.05 T, i H c=955 kA·m -1 , ( BH ) max =207 kJ·m -3 .

关键词： rare earths hot deformation anisotropy sintering

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Observation of ultra-microtexture of fault rocks in shearing-sliding zones

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Progress in Natural sci.nce:Materials International 2005年第5期15卷 430-434页

作者： SUN Yan1*, LU Xiancai1, SHU Liangshu1, GU Lianxing1, ZHU Wenbin1, GUO Jichun1 and LIN Aiming2(1. State Key Laboratory of Mineral Deposits Research, Department of earth sci.nces, Nanjing University, Nanjing 210093, China 2. Department of Geosci.nces, Shizuoka University, Shizuoka 836, Japan) State Key Lab. of Mineral Deposits Res. Dept. of Earth Sci. Nanjing Univ. Nanjing 210093 China dept. of Geosci. Shizuoka Univ. Shizuoka 836 Japan

Based on scanning electronic microscopic observation of three fault rocks in ductile-brittle shearing-sliding zones (including one palimpsest mylonite sampled from deep bore cores of Cajon Pass, California, two flowing-structured carbargillites sampled from Shaancan Well 1 located in north Shaanxi, and Well NH located in Huanghai, respectively), micron- and nanometer-scaled ultra-fine grinding grain texture of fault rocks is discovered in this study. And the geological significance of grinding grain texture is discussed in terms of its particulate organization, rheology of particulate slipping, laminar petrography and micro dynamics including dynamothermal metamorphism, fluid transferring, particulate autorotation, and so on. In addition, the remaining problems to be solved and broad prospects in this new study field are also discussed.

关键词： ductile-brittle shearing zone fault rock texture of grinding grain rheology of particulate slipping.

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