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41.
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Veysel T. Yilmaz Evrim Senel Canan Kazak 《Journal of Inorganic and Organometallic Polymers and Materials》2008,18(3):407-413
The reaction of [Cu(sac)2(H2O)4] · 2H2O with 2-methylpyrazine (mpyz) leads two complexes, concomitant crystallization of a mononuclear complex [Cu(sac)2(mpyz)(H2O)2] (1) and a polymeric complex [Cu(sac)2(μ-mpyz)]n (2). Both complexes have been characterized by elemental analyses, magnetic measurements, FT-IR and ESR, TG-DTA and single-crystal
X-ray diffraction analyses. Single-crystal X-ray analyses show that complex 1 consists of discrete molecules in which the copper(II) ions exhibits a square-pyramidal coordination geometry. The individual
molecules of 1 are connected into a hydrogen-bonded chain structure, which is further assembled to form a three-dimensional network by π–π stacking interactions.
Complex 2 is an 1D coordination polymer in which copper(II) centers are bridged by the mpyz ligand. The chains are further assembled
to form two-dimensional frameworks by π–π and C–H···π stacking interactions. 相似文献
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44.
利用AES、WDS和x-射线衍射等方法,研究了杜美丝表面层、铁镍芯与覆铜层界面的微观结构与特性。结果表明:良好的表面层应由Cu2O和非晶态的硼砂构成;玻璃与杜美丝的润湿性决定于表面层的净化程度和构成及加热条件。 相似文献
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46.
F.A Harraz 《Electrochimica acta》2002,47(8):1249-1257
The effect of chloride ions (Cl−) during the immersion plating of copper onto porous silicon (PS) from a methanol (MeOH) solution has been studied. The presence of Cl− in the Cu2+ solution was found to slow down the rate of copper deposition, as confirmed by inductively coupled argon plasma emission spectroscopy and X-ray photoelectron spectroscopy measurements. The threshold concentration of Cl− at which the deposition of copper is very severely diminished was found to be 0.1 M. The inhibition effect is discussed on the basis of the rest potential values of PS and polarization curve measurements. They revealed that the rest potential of PS upon dipping in these solutions appears to direct the metal deposition. Current density-potential curves show that at Cl− concentrations higher than 0.1 M, the reduction of Cu ions proceeds in two steps; the reduction of Cu(II) to Cu(I) followed by the reduction of Cu(I) to Cu(0). This suggests that Cu(I) species in MeOH solution can be stable over a certain potential range and this stability of Cu(I) is responsible for the inhibition of metal deposition. Fourier transform infrared spectroscopy and scanning electron microscopy (SEM) were also performed to investigate the structural changes and characterizations of PS samples after the plating process. 相似文献
47.
铜电解精炼过程中砷、锑、铋的危害及脱除方式的进展 总被引:6,自引:1,他引:5
在铜电解精炼过程中 ,砷、锑、铋等杂质 ,尤其是锑、铋 ,一直来被人们认为是对阴极铜生产、影响阴极铜质量的最为有害的元素。本文结合贵冶历年的生产实践来讨论砷、锑、铋等杂质在阴极铜生产过程中的危害以及脱除方式的进展。 相似文献
48.
大红山铜矿岩体结构调查分析 总被引:2,自引:1,他引:1
大量工程实践已证明岩体结构是控制岩体稳定性的重要影响因素。为此,以大红山铜矿为研究背景,在选定有代表性调查地段的基础上,引入详细观测线法对其岩体结构进行了详细调查与统计。分析结果表明:调查区域内巷道岩体节理裂隙比较密集和发育,主要发育有倾向N53E、走向N37W、倾角53°,倾向W26S、走向N36W、倾角68°;倾向E1S、走向NIE、倾角89°的三组优势结构面,其中优势结构面第二组和第三组构成不稳定块体,并且断层及软弱夹层比较发育,加剧了巷道的破碎程度,对巷道围岩的稳定性有控制作用。最后提出了在巷道施工中密切注意围岩稳定性变化,避免工程事故的发生的建议。 相似文献
49.
We have made a study of the chemical composition, the electrical, the optical and the structural properties of polycrystalline CuInS2 thin films prepared by spray pyrolysis to be used for thin film solar cells. These films were deposited starting from aqueous solutions with different chemical compositions ([Cu]/[In] and [S]/[Cu] ratios) and at different substrate temperatures. In all cases, the material is p-type with grains preferentially oriented in the (112) direction of the sphalerite structure. The electro-optical properties show a very strong dependence on the [Cu]/[In] ratio in the solution. Films with copper excess have smaller resistivity and better crystallinity than those which are stoichiometric or have indium excess. The results obtained in this work show the possibility of having CuInS2 thin films with a wide range of resistivity, a fact that could be important for making solar cells based on this material. 相似文献
50.
富Ag的Ag—Cu合金再结晶 总被引:1,自引:0,他引:1
用度测量、示差扫描量热(DSC)、金相显微镜、透射电镜等技术研究了富Ag的Ag-Cu合金的再结晶。对合金再结晶温室随Cu含量的变化规律以及在相同变形量下,Cu含量对合金再结晶过程中冷加工储存能的释放的影响进行探索,并讨论了结果。 相似文献