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Continental hydrothermal sedimentary siliceous rock andgenesis of superlarge germanium(Ge)deposit hosted incoal:A study from the Lincang Ge deposit,Yunnan,china

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science china Earth sciences 2004年第11期47卷 973-984页

作者： QI Huawen1,2.HU Ruizhong1,SU Wenchao1,QI Liang1 & FENG jiayi1 1.Key Laboratory of Ore Deposit Geochemistry,Chinese Academy of sciences,Guiyang 550002.china 2.{2. of Earth sciences,nanjing university,nanjing 2.0093,china correspondence should be addressed to Qi Huawen(email: qihuawen@***) Key Laboratory of Ore Deposit Geochemistry Chinese Academy of Sciences Guiyang China department of Earth sciences Nanjing University Nanjing China

There are abundant hydrothermal sedimentary structures and plant fragment fossils in the siliceous rocks from the Lincang Ge deposit. The major element compositions of these siliceous rocks are characterized by high content SiO2. low TiO2.and Al2.3concentrations, and low Al/(Al+Fe+Mn) ratios (0.010 on average). The siliceous rocks are distinctly enriched in Ge, Sb, As, W, and secondly enriched in Cs, U, Mo and Tl. Their total REE content are generally less than 1μg/g, LREE relatively concentrated, and the values of Eu anomaly and Ce anomaly vary from 0.452.to 5.141 and 0.997 to 1.174, respectively. Their NAS-normalized REE patterns are plain or left-inclined. The Oxygen isotope compositions of these siliceous rocks are similar to those of the hydrothermal siliceous sinter. The above characteristics, as well as the geological setting of the deposit, indicate these siliceous rocks formed in continental hydrothermal envi- ronment. As the interlayer or cliff of the Ge-rich coal seams, siliceous rocks tightly contacted with ore-body, and the contents of Ge in siliceous rocks vary from 5.6 to 360 μg/g (78 μg/g on aver- age). The Ge content increased in coal which close to the siliceous rocks. With the increase of Ge content, the typical trace element ratios (i.e., Ge/Ga, Nb/Ta and U/Th) and REE patterns of Ge-rich coal are more close to those of the siliceous rocks. The Ge concentrated in coal seams of the Lincang Ge deposit might be transported by the hydrothermal water, which demonstrated by the siliceous rocks, during the coal-forming processes.

关键词： siliceous rock, continental hydrothermal sedimentation, superlarge Ge deposit, Lincang.

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Piezoresistive effect in carbonnanotube films

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Chinese science Bulletin 2003年第2期48卷 125-127页

作者： LI Yong, WANG Wanlu, LIAO Kejun, HU Chenguo, HUANG Zhi & FENG Qing department of Applied Physics, Chongqing university, Chongqing 400044, {2. correspondence should be addressed to Wang Wanlu (e-mail: wanluw@ ***) department of Applied Physics Chongqing University Chongqing China

The piezoresistive effect of the pristine carbon nanotube (CNT) films has been studied. Carbon nanotubes were synthesized by hot filament chemical vapor deposition. The piezoresistive effect in the pristine CNT films was stud-ied by a three-point bending test. The gauge factor for the pristine CNT films under 500 microstrains was found to be at least 65 at room temperature, and increased with tem-perature, exceeding that of polycrystalline silicon (30) at 35℃. The origin of the piezoresistivity in CNT films may be ascribed to a pressure-induced change in the band gap and the defects.

关键词：碳纲米管薄膜压阻效应应变系数传感器

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Synthesis and reaction of 16-electron Cp^tRh halfsandwich complexes containing 1,2. dichalcogenolate carborane ligands

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Chinese science Bulletin 2003年第16期48卷 1733-1736页

作者： KONG Qingan, jiN Guoxin, CAI Shuyi & WENG Linhong Laboratory of Molecular Catalysis and Innovative Material, Chemistry department, Fudan university, Shanghai 2.0433, {2. correspondence should be addressed to jin Guoxin (e-mail: gxjin@ ***) Laboratory of Molecular Catalysis and Innovative Material Chemistry Department Fudan University Shanghai 200433 China

The reactions of [CptRhCl(m-Cl)]2.(1) (Cpt = tBu2.5H3) with Li2.2.2.10H10 (E = S, Se) lead to the green 16-electron dichalcogenolate complexes CptRh(E2.2.10H10) [E = S(2.), Se(2.)]. The 16-electron complexes 2. and 2. can take up two-electron donor ligands such as tert-butyl isoni-trile and carbon monoxide to give the 18-electron dichalco-genolate derivatives Cpt(L)(E2.2.10H10) [L = tBuNC, E = S(3a), Se(3b); L = CO, E = S(4a), Se(4b)]. The molecular structures of complexes 2. and 3a were determined by X-ray crystal structure analysis. The molecular structure of 16- electron complex 2. shows the pseudoaromatic system in IrSe2.2.five numbered ring.

关键词：碳硼烷配合体化合物异腈一氧化物晶体结构分析分子结构有限环

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The i-E Equations of Steady-state Voltammograms at Microdisk Electrodes

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Chemical Research in Chinese Universities 1993年第2期9卷 110-115页

作者： ZHUANG Qian-kun CHEN Hong-yuan (department of Chemistry, nanjing {2., nanjing, 2.0008) To whom correspondence should be addressed.

Based on the theories of conventional electrodes, as well as the properties of microdisk electrode, the i-E equations for chronoamperometry at disk microelectrode for reversible, quasi-reversible and irreversible systems are derived. Steady-state voltammograms for the oxidation of [Fe(CN)6]4- , Fe2. and ascorbic acid were measured at a series of microdisk electrodes with different radii. The conventional log-plot shows that oxidations of [Fe(CN)6]4- and ascorbic acid are reversible and totally irreversible, respectively, but the oxidation of Fe2. is reversible at larger radius microdisk electrodes and quasi-reversible at smaller radius microdisk electrodes. The application of the log-plot to the voltammograms yielded a straight line, its slope allows us to evaluate the charge transfer coefficient and the intercept gives values of the electron transfer rate constant.

关键词： i-E equation Microdisk electrode Steady-state votammograms

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Synthesis,crystal structure of a novel yttrium (Ⅲ) coordination compound supported by typical plenary Dawson cluster

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Chinese science Bulletin 2003年第23期48卷 2585-2588页

作者： WANG jingping, WEI Meilin & NIU jingyang School of Chemistry and Chemical Engineering, Henan university, Kaifeng 475001, {2. correspondence should be addressed to Niu jingyang (e-mail: jyniu@ ***) School of Chemistry and Chemical Engineering Henan University Kaifeng China

A novel yttrium (III) coordination compound supported by plenary Dawson cluster, [Y(NMP)5(H2.)2. [Y(NMP)4(H2.)2.P2.o18O62.] · NMP · 5.5 H2., (NMP = N-methyl-2.pyrrolidone) has been synthesized by reaction of α-H6P2.o18O62.· nH2., Y2.3 and NMP in water. The results of the single crystal X-ray diffraction analyses show the title compound forms a neutral and discrete cluster through [P2.o18O62.6−] being coordinated to [Y(NMP)4(H2.)2.3+ through its terminal oxygen atom.

关键词：晶体结构钇 X射线衍射分析氧原子

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Molecular self-assembly behavior of mono[6-O-6-(4-carboxyl-phenyl)]-β-CD in solution and solid state

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Chinese science Bulletin 2003年第15期48卷 1535-1538页

作者： FAN Zhi, ZHAO Yanli & LIU Yu department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, nankai {2., Tianjin 300071, china correspondence should be addressed to Liu Yu (e-mail: yuliu@public. ***) department of Chemistry State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China

A novel modified cyclodextrin, mono[6-O-6-(4- carboxyl-phenyl)]-b-CD (1), has been synthesized by the reaction of mono[6-(p-toluenesulfonyl)]- b-CD with 4-hydro- xybenzoate, and its molecular self-assembly behavior in both solution and solid state was studied by means of crystallography, NMR spectroscopy and microcalorimetry. The results indicate that the bezoic acid groups are successively penetrated intermolecularly into the adjacent b-CD cavities to form helical columnar supramolecules in the solid state. As compared with crystal, the similar self-assembly behavior of 1 in aqueous solution has also been confirmed by the 1H ROESY spectroscopy. Thermodynamically, the formation of polymeric supramolecules by modified CD in aqueous solution is mainly driven by entropy changes.

关键词：分子自组装环糊精结晶学微量热法光谱学

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Cryptomelane(KxMn(8-x)O(16)) Natural active octahedral molecular sieve(OMS-2.

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Chinese science Bulletin 2003年第9期48卷 920-923页

作者： LU Anhuai, GAO Xiang, QIN Shan & WANG Changqiudepartment of Geology, Peking university, Beijing 100871. {2. correspondence should be addressed to Lu Anhuai (e-mail: ahlu@ ***) department of Geology Peking University Beijing 100871 China

The Xiangtan manganese deposit (XTM) used to be considered a supergene oxide manganese ore in South china. We reported a new identification of the naturally outcropping cryptomelane by examining the physical, chemical and structural features of the XTM supergene oxide manganese ore. The MnO2.content was over 90%, K2. more than 3%, and water from 2.2.-3.1% which is similar to one in zeolite. The cell parameters of the cryptomelane were given as a0 = 0.9974 nm, b0 = 0.2.63 nm, c0 = 0.9693 nm and β91.47(. There was a larger pseduotetragonal tunnel in the natural cryptomelane that was formed by [MnO6] octahedral double chains with aperture of 0.462.0.466 nm2. filled with K cations resulting in some Mn3+ substituting for Mn4+ to balance the negative charges of structure. The finding is important not only for prospecting manganese resources in South china, but also in application of octahedral molecular sieve of natural cryptomelane as that developed in the tetragonal molecular sieve of natural zeolite over the past century. The XTM cryptomelane (OMS-2. may be the real mineral of the active octahedral molecular sieve in nature.

关键词：隐钾锰矿天然活性分子筛 OMS-2 湘潭锰沉积物浅生矿床氧化物

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The input/removal rates of size-fractionated ^2.0Po in the jiulongjiang estuary and its implications

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Chinese science Bulletin 2003年第21期48卷 2362-2365页

作者： YANG Weifeng, CHEN Min, HUANG Yipu, QIU Yusheng, ZHANG Lei, XING Na & LI Yanping department of Oceanography, Xiamen university, Xiamen 361005, {2. correspondence should be addressed to Huang Yipu (e-mail: yphuang@ ***) department of Oceanography Xiamen University Xiamen 361005 China

The geochemical behaviors of dissolved (15). The input/removal rates of three species indicate that 2.0Po was removed rapidly in the jiu-longjiang estuary. The discrepancy of input/removal rates between 2.0Po species ... 详细信息

The geochemical behaviors of dissolved (2.0Po in surface waters from the jiulongjiang estuary were examined and the input/removal rates of different 2.0Po species were estimated. Both dissolved and low molecular weight 2.0Po were considerably removed during estuarine mixing. However, colloidal 2.0Po was removed only at low salinity regions (S 15). The input/removal rates of three species indicate that 2.0Po was removed rapidly in the jiu-longjiang estuary. The discrepancy of input/removal rates between 2.0Po species suggests different geochemical be-havior and a dynamic transformation between 2.0Po species. Low molecular weight 2.0Po may be more appropriate for characterizing the 2.0Po behavior in estuary zone than the traditional dissolved 2.0Po.

关键词：钋 ^2.0Po 地球化学水污染生态系统

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Rearrangement mechanism of the sodium adducts of Fmoc protected amino acids

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Chinese science Bulletin 2003年第21期48卷 2317-2319页

作者： DU jintang, LI Yanmei, ZHU Zhentai, CHEN Yi & ZHAO Yufen Laboratory of Bioorganic Phosphorus Chemistry, department of Chem-istry, Tsinghua university, Beijing 100084, {2. correspondence should be addressed to Li Yanmei (e-mail: liym@mail. ***) Laboratory for Bioorganic Phosphorus Chemistry Department of Chemistry Tsinghua University China

The cationized 9-fluorenylmethoxycarbonyl (Fmoc) protected amino acids were analyzed by the electros-pray ionization tandem mass spectrometry (ESI-MS/MS). A rearrangement reaction leading to the C-terminal hydroxyl group transfer was observed. The sodium adducts of Fmoc-OH was formed. A possible rearrangement mechanism was proposed. The rearrangement reaction depended on the Fmoc group, metal ions and metal ion radius. It was shown that the Fmoc group has a strong affinity to the hydroxyl group in the gas phase.

关键词：氨基酸钠羟基重组机制金属离子

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Thermodynamic characterization of two novel spin-crossover complexes

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Chinese science Bulletin 2003年第22期48卷 2446-2449页

作者： DING Bin, WANG Hongmei, YI Long, CHENG Peng, LI Licun, ZHAI Yuping, LIAO Daizheng, YAN Shiping & jiANG Zonghui department of Chemistry, nankai {2., Tianjin 300071, china correspondence should be addressed to Cheng Peng or Liao Daizheng (e-mail: pcheng@***) department of Chemistry Nankai University Tianjin 300071 China

Two novel FeII spin crossover complexes [Fe(L1)3](BF4)2.H2. (1) and [Fe(L2.3](BF4)2.2.2. (2. with 4-NHR-1,2.4-triazole (R = isopropyl, L1; cyclohexyl, L2. were synthesized. 1 and 2.remain white at room temperature, whereas they turn purple at liquid temperature. Variable temperature optical detection and magnetic susceptibilities measurement show that the spin-crossover phenomenon for 1 was observed between 12. K and 170 K. The hysteresis loop is about 10 K. The Tc temperature of 2.is 190 K, but no thermal hysteresis loop was found. The molar thermodynamic functions and the microscopic parameters were obtained from the theoretical analysis in terms of the domain model, two level Ising model and regular solution model, respectively.

关键词：热力学性质铁磁化系数磁滋环旋转截面化合物记忆功能

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