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Science china Earth Sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2. LUO Xingzhang3, WANG Ju4, JIN Yuanxin4 & WANG Rucheng1 1. Department of Earth Sciences, State Key Laboratory of Mineral Deposit Research, nanjing university, nanjing 210093,{2. 2. center of materials analysis, nanjing university, nanjing 210093,{2. 3. Department of Environmental Science and Engineering, nanjing university, nanjing 210093,{2. 4. Beijing Geology Institute, Nuclear Industry, Beijing 10002.,{2. nanjing university Nuclear Industry

The first results of sorption experiments of U(VI), 2.4U(VI) and 2.8U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, china are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in china. The present experimental results show that the maximum U(VI) sorption reached 92. at near-neutral pH and the distribution coefficient (Kd) was 12.6 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 2.4U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

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色谱法分析环境中铝形态的进展

色谱 2003年第1期21卷 38-43页

作者：康玉芬练鸿振艾尔肯.牙森田笠卿南京大学化学系江苏南京210093 南京大学现代分析中心江苏南京210093

综述了色谱法在环境体系铝形态研究中的应用进展,比较了离子交换色谱、体积排阻色谱、反相高效液相色谱、快速蛋白质液相色谱、毛细管电泳以及流路中嵌入色谱小柱的流动注射分析法的优缺点。引用文献55篇。

关键词：铝形态分析色谱法土壤溶液天然水

Study on lithogeochemistry of Middle Jurassic basalts from southern china represented by the Fankeng basalts from Yongding of Fujian Province

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Science china Earth Sciences 2006年第10期49卷 1020-1031页

作者： ZHOU Jincheng1,2. JIANG Shaoyong1,2. WANG Xiaolei1,2. YANG Jinghong 1,2.& ZHANG Mengqun 3 1. State Key Laboratory of Mineral Deposit Research, nanjing university, nanjing 210093,{2. 2. Department of Earth Sciences, nanjing university, nanjing 210093,{2. 3. Modern analysis center, nanjing university, nanjing 210093,{2. State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China Department of Earth Sciences Nanjing University Nanjing China Modern analysis center Nanjing University Nanjing China

There exists an E-W trending Middle Jurassic volcanic zone in southern china. The Fankeng basalts in the Yongding basin of Fujian Province are considered to be a typical example. The Fankeng basalts have TiO2.contents in the range of 1.92.-3.2.%. They are classified as high-Ti basalts. They also have higher total Fe (averaging FeO* = 11.09%). The Middle Jurassic Fankeng basalts from southwestern Fujian have obvious distinctive lithogeochemical features from early Cre- taceous basalts from southeastern coast of china. They have higher HFSE, such as Th, Nb, Ta, Zr and Ti. Their element ratios related with HFSE, such as Zr/Ba, La/Nb, La/Ta ,Zr/Y, Ti/Y, Ba/Nb, K/Ti and Rb/Zr are similar to those of OIB. The most samples have ε Nd(T) of-0.70-0.2., which are near chondrite. Some samples have higher ε Nd(T) of ***, these basaltic magmas might be derived from depleted asthenospheric mantle. The lithogeochemical characteristics of the Fankeng basalts may be caused by interaction between asthenosphere and lithosphere at the time. The (Early-) Middle Jurassic basalts and gabbros from southeastern Hunan, southern Jiangxi and northern Guangdong provinces show similar geochemical features to those of the Fankeng basalts from the Yongding of Fujian. Occurrence of these OIB-type basalts in the area may be regarded as the petrological mark of upwelling of asthenosphere at the time. Upwelling of asthenosphere has led to tectonic extension and the formation of rifted basin in the area.

关键词： interaction between asthenosphere and lithosphere, lithogeochemistry, basalts, Middle Jurassic, southern china.

EPR studies of Mn^(2.) in the Loess Plateau of central china: Implication for variation of the East Asia summer monsoon

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Chinese Science Bulletin 1998年第1期43卷 72-75页

作者： CHEN Jun\+1, JI Junfeng\+1, SU Yuanxia\+2.and LU Huayu\+31. Department of Earth Sciences, nanjing university, nanjing 210093,{2. 2. center of Material analysis, nanjing university, nanjing 210093,{2. 3. Xi’an Laboratory of Loess and Qu Department of Earth Sciences Nanjing University Nanjing China center of Material analysis Nanjing University Nanjing China Xi’an Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an China

Mn 2. EPR intensity recorded in the Chinese loess_paleosol sequence shows close correlation with magnetic susceptibility and Sr content as well as the oscillation of paleoclimate. Thus Mn 2. EPR signal can serve as an... 详细信息

关键词： paleomonsoon loess paleosol EPR signal of Mn 2.

Ultra-microbes are the minerogenetic constructors of oceanic polymetallic nodules

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Chinese Science Bulletin 1997年第8期42卷 617-624页

作者： CHEN Jianlin, ZHANG Fusheng and BIAN Lizeng1 Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012. china 2.center for {2. analysis, nanjing university, nanjing 210093, china 3. Department of Earth Sciences, nanjing university, nanjing 210093, china Second Institute of Oceanography State Oceanic Administration Hangzhou China Centu for materials analysis Nanjing University Nanjing China Department of Earth Sciences Nanjing University Nanjing China

Polymetallic nodules (mangnese nodules) are a typical kind of manganese oncolites The distribution of smooth sur-face and knobbly manganese nodules is closely related to the geological background of the mine field. A systematic study on their inner laminae structure and features suggests that they are the products of millions of years reproduction and accumulation of the recently found Miniactinomyces chinensis and Spirisophaerospora pacijica .

关键词： oceanic manganese nodule stromatolite ultra-microbe biolite.

Crystal structure and single crystal EPR of (NH_4)_2.15-crown-5)_3[Cu(mnt)_2. and (NH_4)_2.benzo-15-crown-5)_4[Cu(mnt)_2.·0.5H_2.

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Science china Chemistry 2007年第5期50卷 607-613页

作者： SUI YunXia1, WEN LiLi2. ZHANG Huan3 & MENG QingJin2.1 center of Modern analysis,{2., nanjing 210093, china 2.State Key Laboratory of Coordination Chemistry, Coordination Chemistry Institute,{2., nanjing 210093, china 3 Jiangnan Institute of Computing Technology, Wuxi 2.4083, china center of Modern analysis Nanjing University Nanjing China State Key Laboratory of Coordination Chemistry Coordination Chemistry Institute Nanjing University Nanjing China Jiangnan Institute of Computing Technology Wuxi China

The X-ray crystal structures of (NH4)2.15-crown-5)3[Cu(mnt)2. (1) and(NH4)2.benzo-15-crown-5)4-[Cu(mnt)2. ident to 0.5H2. (2. were *** single crystals arecomposed of distinct structures of ammonium-crown ether supramolecular cation and [Cu(mnt)2.^(2.)*** triple-decker dication in complex 1 and a sandwich dimmer in complex 2.wereobserved.X-Band EPR studies on the single crystals of both complex 1 and complex 2.have been carriedout at room temperature,which revealed that complex 2.showed a perfect hyperfine structure of Cuwhereas that of complex 1 could not be *** principal values and direction cosines of theprincipal axes of the g and A tensors were computed by a least-squares fitting *** spindensity of Cu(ll) was estimated according to the principal values of the A tensors and compared wellwith the results calculated based on DFT method.

关键词： supramolecular cation, H-bonding interaction, EPR, g and A tensors, DFT

Preparation and Characterization of Nanocomposite MgFe_2._4/SiO_2

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Journal of Wuhan university of Technology(materials Science) 2009年第3期24卷 354-358页

作者：徐莉 College of Science Nanjing Forestry University

Nanocomposites MgFe2.4/SiO2.were successfully synthesized by the sol-gel method in the presence of N, N-dimethylformamide （DMF）. The formation of pure MgFe2.4 was confirmed by powder X-ray diffraction （XRD） and electron diffraction. The structural evolution of MgFe2.4 nanocrystals was followed by powder X-ray diffraction and IR absorption spectroscopy. The formation of spinel structure of MgFe2.4 started at 800 ℃, and completed at 900 ℃, The transmission electron microscopy （TEM） measurements suggest that the particle sizes increase with the increasing annealing temperature, and the mean particle sizes of the spherical samples annealed at 800 ℃, 900 ℃ and 1 050 ℃ are ca. 3 nm, 8 nm and 11 nm, respectively. Magnetization measurements at room temperature and 78 K indicate supemaramagnetic nature of these MgFe2.4 nanocrvstals.

关键词： nanocomposite sol-gel magnesium ferrite magnetic property

On the variational principle for the topological pressure for certain non-compact sets

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Science china Mathematics 2010年第4期53卷 1117-1128页

作者： PEI Yu 1 & CHEN ErCai 1,2.1 Department of Mathematics,nanjing Normal university,nanjing 2.0097,china 2.center for Nonlinear Science,nanjing university,nanjing 210093,china Department of Mathematics Nanjing Normal University Nanjing China center for Nonlinear Science Nanjing University Nanjing China

Let (X,d,T) be a dynamical system,where (X,d) is a compact metric space and T:X → X is a continuous *** assume that the dynamical system satisfies g-almost product property and the uniform separation *** compute the topological pressure of saturated sets under these two *** the uniform separation property does not hold,we compute the topological pressure of the set of generic *** give an application of these results to multifractal analysis and finally get a conditional variational principle.

关键词： uniform separation property g-almost product property topological pressure of non-compact sets variational principle BS-dinmension

IR STUDY ON MONOMOLECULAR PARTICLE AGGLOMERATES OF POLYSTYRENE OBTAINED BY FREEZE-DRYING OF ITS DILUTE SOLUTION

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Chinese Journal of Polymer Science 2002年第4期20卷 381-383页

作者： Song Wang Qing-hua Wang Rong-shi Cheng Research center of materials Beijing Institute of Technology Beijing 100081,{2. Department of Chemistry nanjing university nanjing 210093,{2. Research center of materials Beijing Institute of Technology 北京 100081 Department of Chemistry Nanjing University Nanjing 210093

The monomolecular particle agglomerates of polystyrenes were obtained by freeze-drying of its very dilute solutions of 1.3 x 10(-5)-2.0 x 10(-5) g/mL in benzene:cylcohexane (100:1) solvents, and they were annealed at room temperature for hundred days before use. According to C-13-NMR measurement the polystyrenes should be practically atactic. The number average molecular weights of the samples are 2.80 x 10(3), 2.00 x 10(4), and 1.55 x 10(6), respectively. The freeze-dried aPS with a molecular weight higher than 10(4) show two new IR absorption bands at 1098 and 12.1 cm(-1), which are absent in the normal aPS and freeze-dried styrene oligomer. It was also found that the low molecular weight samples can only form powders, whereas the freeze-dried aPS with higher molecular weight form a mixture of powders and fibrils, of which the longer fibrils show a much stronger 12.1 cm(-1) band than the shorter fibrils and the powder. It seems that the 12.1 cm(-1) band corresponds to the stacking behavior of monomolecular particles.

关键词： monomolecular particles atactic polystyrene FTIR spectroscopy

An SANS Study of Decomposition Kinetics in Amorphous Cu_(12.5)Ni_(10)Zr_(41)Ti_(14)Be_(2..5)

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Journal of materials Science & Technology 1998年第3期14卷 193-199页

作者： Junming LIU(National Laboratory of Solid State Microstructures, nanjing university and center for Advanced Studies in Scienceand Technology of Microstructures,{2., china) National Laboratory of Solid State Microstructures Nanjing University Center for Advanced Studies in Science and Technology of Microstructures Nanjing 210093 China

Phase decomposition in amorphous Cu12.5Ni10Zr411Ti14Be2..5 alloy as annealed in the super-cooled liquid range was studied by applying small angle neutron scattering (SANS). As annealed between 600 K and 700 K, the alloy was observed to decompose into two new amorphous phases,with the second phase precipitates embedded in the matrix of the first. Long time annealing of the alloy results in crystallization in addition to evolution of the decomposed *** kinetic diagram of the decomposition and crystallization for this alloy is given. The second phase precipitates have several nanometers in size and occupy a quite low volume fraction. The decomposition of the supercooled liquid in overall temperature range exhibits the features of spinodal reaction.

关键词： Be Zr SANS Ni Ti