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Synthesis,structural characterization and properties of a 3D infinitely extended structural rare earth coordination compound of K_3{[Sm(H_2O)_7]_2Na[α-SiW_(11)O_(39)Sm(H_2O)_4]_2}·14 H_2O

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Science China Chemistry 2005年第4期48卷 343-351页

作者： WANG Jingping ZHAO Junwei NIU Jingyang Institute of Molecule and Crystal Engineering School of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475001China Institute of Molecule and Crystal EngineeringSchool of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475001China Institute of Molecule and Crystal EngineeringSchool of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475001China

A 3D infinitely extended structural rare earth coordination compound with a formula of K3{[Sm(H2O)7]2Na[a-SiW11O39Sm(H2O)4]2}·14H2O has been synthesized by reaction of Sm2O3,HClO4,NaOH with a-K8SiW11O39·nH2O,and characterized by IR,UV spectra,ICP,TG-DTA,cyclic voltammetry,variable-temperature magnetic susceptibility and X-ray single-crystal diffrac-tion.X-ray single-crystal diffraction indicates that the title compound crystallizes in a triclinic lat-tice,Pi space group,with a = 1.2462(3) nm,b = 1.2652(3) nm,c = 1.8420(4) nm,α = 87.45(3)°,β = 79.91(3)°,γ = 82.57(3)°,Z = 1,R1 = 0.0778,wR2 = *** analysis reveals that Sm3+(1) coordination cation has incorporated into the vacant site of [α-SiW11O39]8? entity,forming the [α-SiW11O39Sm(H2O)4]5? *** two adjacent [a-SiW11O39Sm(H2O)4]5? subunits are combined with each other through two Sm(1)-O-W bridges accompanying the formation of dim-mer structural unit [α-SiW11O39Sm(H2O)4]210? of the title *** neighboring dimmer structural units [α-SiW11O39Sm(H2O)4]210? are linked to form the 1D chainlike structure by means of two Sm3+(2) and a Na+(1) coordination *** K+(1) cations connect the 1D packing chains constructing the 2D netlike structure,and adjacent netlike layers are also grafted by K+(2) cations to build the novel 3D infinitely extended *** result of TG-DTA curves manifests that the decomposition temperature of the title polyanionic framework is 554℃.The cyclic volt-ammetry measurements show that the title polyanion has the two-step redox processes in aqueous solution with pH = *** temperature magnetic susceptibility indicates the title compound obeys the Cruie-Weiss Law in the higher temperature range from 110 to 300 K,while in the lower temperature range from 2 to 110 K the comparatively strong antiferromagnetism in-teractions can be observed.

关键词： silicotungstic acid, Keggin structure, crystal structure, polyoxometal.tes, rare earth metal.

Defect of nanocrystalline copper and silver

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Science China Chemistry 1998年第1期41卷 30-35页

作者：张志琨崔作林郝春成董立峰孟照国于立言 Research Center of Nanocrystalline Materials Qingdao Institute of Chemical Technology Qingdao China

Nanoscale copper and silver were synthesized by the H 2+Ar arc plasma method. During the synthesis, hydrogen molecules were dissociated into hydrogen atoms and stored in the particles. At the same time, nanometer copper and silver particles were prepared by the inert gas condensation method whose power is about identical with the hydrogen arc plasma method. Various specimens were annealed respectively at low temperature. The particle size was measured by a transmission electron microscopy. A proper temperature was chosen to prepare the standard specimen. The defects of nano copper and nano silver were studied by TEM, HRTEM, XRD profile refinement and Fourier analysis method. The asymmetry of XRD profile of both specimens was discovered and the significance of the asymmetry was studied. The probability of twin existing in the nano materials was calculated using Fourier analysis method, and the effect of hydrogen on the structure was discussed.

关键词： defect nanocrystalline metal.

Optical properties of nano-size ZnS semiconductor microcrystals doped with Mn^(2+) ions

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Chinese Science Bulletin 1995年第21期40卷 1782-1784页

作者：靳春明侯尚公窦恺陈一民黄世华虞家琪 Changchun Institute of Physics Chinese Academy of Sciences Changchun 130021 China

In recent years, me synthesis and optical properties of nano-size semiconductor particles were studied more extensively. Semiconductor (such as ZnS, CdS and GaP) nanometer microcrystallites were prepared in polymers, organic solutions and glasses. The quantum-size effects occurred and the optical properties were changed in those materials as the microcrystal radius decreased. Most of the previous studies were devoted to understanding the intrinsic properties and the interaction with surrounding medium. Bhargava

关键词： Mn2+-doped semiconductor microcrystals optical properties colloidal method transition metal.

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罗源湾海水中重金属的调查研究

厦门大学学报（自然科学版） 1989年第S1期28卷 144-147页

作者：邹栋梁高淑英厦门大学海洋学系

为了开发利用罗源湾,我们于1986年11月至1987年9月调查了海水中重金属,报道了罗源湾海水中Cu,Pb,Zn,Cd,Hg②的含量及其分布特征,并着重研究了表层海水中Cu,Pb,Zn,Cd含量与盐度的关系。

关键词： Heavy metal. Survey. Extraction. GFAAS Salinity