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Magnetic mineralogy of the Hongqiling Cu-Ni sulphide deposit: Implications for ore genesis

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Progress in Natural Science:Materials International 2007年第10期17卷 1192-1198页

作者： Xi Aihua1,2. Ge Yuhui1, Cai Yuanfeng2.and Zhang Xuefeng3(1. Faculty of Resources & Environment, Southwest Petroleum university, Chengdu 610500, china {2., nanjing university, nanjing 2.0093. china 3. Department of Natural Resources & Technology Information, china university of Petroleum, Beijing 102.49, china) Faculty of Resources and Environment Southwest Petroleum University Chengdu 610500 China state key {2. for endogenic metal deposit research Nanjing University Nanjing 210093 China Department of Natural Resources and Technology Information China University of Petroleum Beijing 102249 China

Pyrrhotite is one of the common ore minerals in Cu-Ni sulphide deposits, but only monoclinic pyrrhotite is ferromagnetic at room temperature. X-ray and EPA analyses reveal that most pyrrhotite forming sideronitic texture in the Hongqiling Cu-Ni sulphide deposit is monoclinic, but that in the massive ore is a mixture of monoclinic and hexagonal pyrrhotites. Differential thermal and magnetic- thermogravimetric analyses of massive ore indicate a magnetic transition and heat absorption at 32.℃, suggesting that this temperature is the thermomagnetic and phase transition point of pyrrhotite. For massive pyrrhotite ores heated at 400oC for 30 h and then quenched by cool water, the monoclinic pyrrhotite (mpo) transforms completely into the hexagonal pyrrhotite (hpo). However, all the pyrrhotites resulting from slow cooling of the sample in air are mpo. These results indicate that transformation between hpo and mpo depends upon the cooling rate. Therefore, massive ores in this deposit might have been formed via rapid cooling of ore melts. On the other hand, it is significant to study the effect of the ratio of the magnetite in total ores on the genesis of magmatic Cu-Ni suphide deposits.

关键词： pyrrhotite magnetite genesis of Cu-Ni sulphide deposit Hongqiling.

Sensitive biosensing strategy based on functional nanomaterials

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Science china Chemistry 2011年第8期54卷 1202-1217页

作者： JU HuangXian state key {2. of Analytical Chemistry for Life Science Department of Chemistry, nanjing university, nanjing 2.0093. china state key {2. of Analytical Chemistry for Life Science Department of Chemistry Nanjing University Nanjing China

The first decade of the 2.st century has been labeled as "the sensing decade". The functional nanomaterials offer excellent platforms for fabrication of sensitive biosensing devices, including optical and electronic biosensors. A lot of works have fo- cused on the biofunctionalization of different nanomaterials, such as metal nanoparticles, semiconductor nanoparticles and carbon nanostructures, by physical adsorption, electrostatic binding, specific recognition or covalent coupling. These biofunc- tionalized nanomaterials can be used as catalysts, electronic conductors, optical emitters, carriers or tracers to obtain the ampli- fied detection signal and the stabilized recognition probes or biosensing interface. The designed signal amplification strategies have greatly promoted the development of stable, specific, selective and sensitive biosensors in different fields. This review in- troduces some novel principles and detection strategies in the area of biosensing, based on functional nanomaterials. The gen- eral methods for biofunctionalization of nanomaterials with biomolecules and their biosensing application in immunoassay of protein, DNA detection, carbohydrate analysis and cytosensing are also described.

关键词： nanobiosensing biosensors nanomaterials biofunctionalization signal amplification bioanalysis biological recognition

Syntheses,crystal structures and properties of three novel coordination polymers with tripodal imidazole-containing ligands and benzenetetracarboxylate

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Science china Chemistry 2010年第10期53卷 2164-2169页

作者： SU Zhi, FAN Jian & SUN WeiYin state key {2. of Coordination Chemistry nanjing National {2. of Microstructures Coordination Chemistry Institute, School of Chemistry and Chemical Engineering, nanjing university, nanjing 2.0093. china state key {2. of Coordination Chemistry nanjing National laboratory of Microstructures Coordination Chemistry Institute School of Chemistry and Chemical Engineering Nanjing University Nanjing China

Three novel coordination polymers, [Ni2.tib)2.btec)]·2.2. (1), [Co2.tib)2.btec)]·2.2. (2. and [Zn4(tib)2.btec)Cl4]·2.2. (3), have been synthesized by using mixed ligands of 1,3,5-tris(1-imidazolyl)benzene (tib) and 1,2.4,5-benzenetetracarboxylic acid (H4btec) under hydrothermal conditions. Complexes 1 and 2.have the same structure and are rare three-dimensional (3D) self-penetrating (3,4,5)-connected nets, while complex 3 is an unprecedented (3,4)-connected 3D net. The different structures of 1 (2. and 3 are ascribed to the distinct coordination geometry of the metal centers. The thermal stability and photoluminescence property of the complexes were investigated.

关键词： coordination polymer self-penetration crystal structure thermal stability photoluminescence property

One-dimensional metal phosphonates based on 6-phosphononicotinic acid:A structural and magnetic study

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Science china Chemistry 2010年第10期53卷 2112-2117页

作者： WANG PengFei, DUAN Yan & ZHENG LiMin state key {2. of Coordination Chemistry Coordination Chemistry Institute, School of Chemistry and Chemical Engineering, nanjing university, nanjing 2.0093. china state key {2. of Coordination Chemistry Coordination Chemistry Institute School of Chemistry and Chemical Engineering Nanjing University Nanjing China

The reactions of 6-phosphononicotinic acid (pnaH3) and metal salts result in three new compounds, namely, M(pnaH)-(H2.)3·H2. [M = Co(Ⅱ) (1), Ni(Ⅱ) (2., Zn(Ⅱ) (3)]. These compounds are isostructural and contain 2. helical chains made up of corner-sharing {MO5N} octahedra and {PO3C} tetrahedra. The chains are further connected by extensive hydrogen bonds to form a three-dimensional supramolecular structure. Magnetic studies reveal that dominant antiferromagnetic interactions are mediated in both 1 and 2. Interestingly the dehydrated compound 1 shows metamagnetic behavior at low temperature.

关键词： carboxylate-phosphonate coordination polymer magnetic property metamagnetism

Syntheses, properties and structures of copper and nickel complexes of 6,7-dihydro-5H-1,4-dithiepin-2.3-dithiolate

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Chinese Journal of Chemistry 1994年第3期12卷 248-257页

作者： YAO, Tian-Ming YOU, Xiao-ZengCoordination Chemistry Institute, state key {2. of Coordination Chemistry, nanjing university,nanjing 2.0008, chinaYANG, Qing-ChuanChemistry Department, Beijing university, Beijing 100871, china Coordination Chemistry Institute State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210008 China Chemistry Department Beijing University Beijing 100871 China

The reaction of CuCl2.2.2. or NiCl2.6H2. with K2.C5H6S4) [potassium salt of 6,7-dihydro-5H-1,4-dithiepin-2.3-dithiolate] under nitrogen atmosphere resulted in the isolation of [Cu(C5H6S4)2.- or [Ni(C5H6S4)2.- as the tetrabutylammonium salt. Both complexes show characteristic IR and UV-Vis absorptions of transition metal dithiolenes. Cyclic voltammograms contain two waves indicating a two step electrochemical procedure [M(C5H6S4)2.0 = [M(C5H6S4)2.1-= [M(C5H6S4)2.2.. Single crystal structure study has been carried out on the nickel complex. Crystal of [Bu4N][Ni(C5H6S4)2. belongs to monoclinic space group P2./c with a=17.576(5), 6=10.883(2., c=17.773(4) A,B=91.07(2.0, Z=4, and o(calcd.)=1.348 g/cm3. Final result is R=0.059 for 2.59 reflections. The NiS4 core exhibits square planar coordination with average Ni-S bond length of 2.134(5) A. There are not anion pairs in crystal. The anions stack along a and c axes while the cations intercalate in them. The nearest S-S contact is 4.42. A. The solid powder ESR spectrum of the nickel complex shows three broadening signals at g1=2.097, g2.2.042. g3=2.02.. Magnetic susceptibility data for [Bu4N][Ni(CgH6S4)2. reveal enhanced anti-ferromagnetic interaction.

关键词： Dithiolene complex copper nickel single crystal.

Influences of low-Ti substitution for La and Mg on the electrochemical and kinetic characteristics of AB_3-type hydrogen storage alloy electrodes

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Science china(Technological Sciences) 2010年第1期53卷 242-247页

作者： DONG ZhenWei1,2.WU YaoMing1,MA LiQun2.SHEN XiaoDong2.& WANG LiMin1 1 state key {2. of Rare Earth Resource Utilization,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,C hangchun 13002.,china 2.College of Material Science and Engineering,nanjing university of Technology,nanjing 2.0009,china state key {2. of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China College of Material Science and Engineering Nanjing University of Technology Nanjing China

The(La0.67Mg0.33)1-xTixNi2.75Co0.2.(x = 0,0.05,0.10,0.15 and 0.2.,at%) alloys were synthesized by arc melting and subsequent heat solid-liquid diffusing *** structure,electrochemical properties and kinetic characteristics of the alloys were investigated *** results showed that all the alloys mainly consisted of the(La,Mg)Ni3,LaNi5 phases,and the lattice parameters and the cell volumes of the(La,Mg)Ni3 and LaNi5 phases decreased with increasing Ti *** alloy electrodes could be activated to reach their maximum discharge capacity within five *** cycle life after 100 charge/discharge cycles(C100/Cmax) and the high-rate dischargeability at a discharge current density of 12.0 mA/g first increased and then *** the results showed that low-Ti content in AB3-type hydrogen storage alloys was beneficial to improvements of the overall electrochemical properties,and the optimum overall electrochemical performance of the alloy electrodes was obtained when x = 0.05.

关键词： AB3-type alloy metal hydride electrode microstructure electrochemical property kinetic characteristic

metals Supported Water Monomers:the Bonding Nature Revisited

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Journal of Materials Science & Technology 2010年第2期26卷 97-105页

作者： Jibiao Li, Shenglong Zhu and Fuhui Wang state key {2. for Corrosion and Protection, Institute of metal research, Chinese Academy of Sciences, Shenyang 110015, china state key {2. for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

A single water monomer is known as a hard-to-observe molecule even in the presence of metal surfaces as supporting matrix. This review highlights effort in experimental characterizations and theoretical modeling of transition metals supported water monomers with attention given to its structure and bonding, together with the insights that we have provided into the bonding nature of the water-interactions by the newly employed projected PDOS （partial density of {2.s） difference analysis, which is proved to be an effective tool to be elucidate such bonding nature. The general s-d hybridization and d-shell effect are summarized, and how these effects can be tuned by tailoring local surface configurations is discussed.

关键词： Water monomer Adsorption Surface bonding Transition metals

LOW POTENTIAL ELECTROPOLYMERIZATION OF ANISOTROPIC CONDUCTIVE POLYTHIOPHENE FILMS AND FABRICATION OF ELECTRICAL DEVICES

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Chinese Journal of Polymer Science 1999年第2期17卷 99-111页

作者： Xiao-bo Wan Yun Lu Xiao-rong Liu Liang Zhou Shi Jin Gi Xue Department of Polymer Science and Engineering, the state key {2. of Coordination Chemistry, nanjing university, nanjing 2.0093. china 南京大学配位化学国家重点实验室江苏南京 210093 南京大学配位化学国家重点实验室江苏南京

The Complexation of thiophene with a Lewis acid with moderate acidity as a solvent, such as BF3-ethyl ether (BFEE) remarkedly lowered the electrochemical polymerization potential. The positively charged metal surface of electrode in the process of electrochemical deposition enhanced the coordination interaction between pi-electrons of thiophene unit and the metal, which makes thiophene rings lie parallel to the surface of electrode, resulting in a highly ordered polymeric structure. Because of the large intra-chain transfer integrals, the transport of charge is believed to be principally along the conjugated chains, which is much greater than the inter-chain hopping. The specific electrical resistance across the polythiophene film thickness is more than 10(4) times than that along the surface plane of the film. In this paper we review the recent development of polymerization technique by low potential electrochemical method performed in our lab and several electrical devices in which the compact polythiophene films, such as anionic and cationic sieves, and laminate film junction of undoped polythiophene derivatives were used.

关键词： conductive polymer polythiophene anisotropy electric device film junction

Electrochemical Corrosion Behavior of Nanocrystalline Materials-a Review

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Journal of Materials Science & Technology 2010年第1期26卷 1-14页

作者： Li Liu, Ying Li and Fuhui Wang state key {2. for Corrosion and Protection, Institute of metal research, Chinese Academy of Sciences, Shenyang 110016, china state key {2. for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Nanocrystallization significantly influences the electrochemical corrosion behaviors of metals/alloys in liquid system. In active dissolution, nanocrystallization accelerates the corrosion reactions. If the corrosion products are dissoluble, the corrosion rate is increased by nanocrystallization; if the corrosion products are insoluble, the corrosion rate is decreased on the contrary because the corrosion products act as a block layer to delay the dissolution. In passivation, nanocrystallization changes the composition of the passive film, and results into different morphology and growth process of the passive film, both of which improves the formation of compact film and influences the semiconductor property. It influences the passivation depending on fast element diffusion and special adsorbed ability. The small grain size improves the element diffusion, which leads to the different composition of passive film （passive elements enrichment such as Cr, Ti）. The small grain size also changes the surface condition, which influences the ions adsorption. All increase the corrosion resistance of materials. In local corrosion, nanocrystallization increases the unstable points on the surface of the materials, which increases the possibility of local corrosion. However, the excellent ability of element diffusion helps heal the local corrosion points, which inhibits the growth of the local corrosion.

关键词： Nanocrystalline materials Electrochemical corrosion Review