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21.
ICP-AES测定铜合金中的铜及10种杂质元素   总被引:1,自引:0,他引:1  
李莉 《光谱实验室》2013,30(5):2700-2703
建立了ICP-AES同时测定铜合金中铜及杂质元素磷、硅、锰、铁、镍、钴、锌、铅、铝、锡11种元素的分析方法,通过对样品溶解方法、元素分析谱线的选择和仪器分析参数进行试验比较,确定了实验条件,并对铜合金标准样品进行了精密度和回收率实验.结果表明,相对标准偏差小于3.0%,回收率在90%-110%之间.该方法快速简便,准确度高,可以满足日常检验的分析要求.  相似文献   
22.
S. Chalker  T.S. Nunney 《Surface science》2006,600(11):2364-2371
The adsorption of dimethylamine on Cu(1 1 0) and Ni(1 1 1) has been studied by reflection absorption infrared spectroscopy. For Cu(1 1 0), adsorption was molecular at 80 and 300 K and for submonolayer dimethylamine the appearance of A′ and not A″ modes indicated Cs symmetry. Similar bonding was found for Ni(1 1 1) at 170 K. Annealing the adlayer to 350 K resulted in the formation of a new species on Ni(1 1 1), similar to that which has been identified as methylaminocarbyne on Pt(1 1 1). In contrast only molecular dimethylamine was identified on Cu(1 1 0), with H-bonded interactions at high coverage and a potential surface dimer.  相似文献   
23.
M.C.G. Lim  Z.W. Zhong 《Physica A》2011,390(5):963-971
The effects of electromigration on copper in carbon nanotube (CNT) channels are investigated using molecular dynamics simulations. The study shows that the potential energy of copper and the resistive forces on copper are dependent on the shape of the CNT junction, and the increase in bias voltages magnifies these effects. Bias voltages affect the density of copper in the downstream CNT. The velocity of copper in the downstream CNT is relatively lower than that in the upstream CNT when the biased voltage is high.  相似文献   
24.
To improve adhesion between copper and epoxy resin in printed circuit board, a roughness treatment of copper has been widely used. Nevertheless, new adhesion promoters have to be developed to face the miniaturization and sophistication of the electronic device. Self-assembled monolayers have met increasing interest in this field by using them as coupling agent between copper and the epoxy resin.This paper presents the deposition of an epoxy resin on copper modified by amine alkylthiol and dithiol monolayers and highlights the benefit brought by the monolayer in terms of adhesion.The chemical linkage between the amine SAMs and the epoxy function has been proved by the deposition on a short epoxy fragment, the 2-(4-fluorophenoxy-methyl)oxirane. The deposition of an epoxy resin mixed with amine curing agent has then been successfully achieved on amine terminated SAMs. The resulting polymer is homogeneous and well adherent on their surface, while the adhesion is lower on bare copper and not existing on methyl terminated SAMs. The formation of chemical bond Cu-S and N-epoxy is thus essential to increase the adhesion strength between copper and the polymer.  相似文献   
25.
Water-soluble CdSe quantum dots (QDs) were synthesized using mercaptosuccinic acid (MSA) as a stabilizer. The growth process and characterization of CdSe quantum dots were determined by transmission electron microscopy (TEM), X-ray diffraction (XRD), photoluminescence (PL) spectroscopy, Ultraviolet-visible (UV-vis) spectroscopy, and Fourier transform infrared (FT-IR) spectroscopy. Results demonstrated the MSA-capped CdSe QDs were highly crystalline and possessed good optical properties. Further, the resulting products could be used as fluorescent probes to detect Cu2+ ions in physiological buffer solution. The response was linearly proportional to the concentration of Cu2+ ion in the range 2×10−8- 3.5×10−7 mol L−1 with a detection limit of 3.4 nmol L−1.  相似文献   
26.
The formation of Co films on polycrystalline copper in diluted sulphuric acid was investigated by employing cyclic voltammetry (CV), atomic force microscopy, and in-situ magneto-optic Kerr effect (MOKE) techniques. By comparing CV measurements in the pure supporting electrolyte (11 mM K2SO4/1 mM H2SO4) and the cobalt sulphate solution (10 mM K2SO4/1 mM H2SO4/1 mM CoSO4), peaks from voltammetric cycling for copper dissolution, readsorption of dissolved copper ions, cobalt bulk dissolution and oxidation of hydrogen could be resolved. As the electroplating time increases, the size of the Co clusters increases and the deposition of Co corresponds to island growth. The first hysteresis loop occurs at a Co thickness of 0.33 nm in the longitudinal configuration. For films thinner than 7 nm, the Kerr intensity increases linearly because the Curie temperature of the film is well above 300 K.  相似文献   
27.
本文研究了新试剂 2 -羧基 - 5 -硝基苯基重氮氨基 - 4 -苯基 - 2 -噻唑 ( CNPDAPT)在 Triton X- 1 0 0的存在下 ,与铜显色反应的适宜条件。结果表明在 p H1 0 .0的 Na2 B4O7- Na OH缓冲介质中 ,铜与试剂形成 1∶ 1红色配合物 ,其最大吸收波长位于 5 1 5 nm,表观摩尔吸光系数 ε=4.5 9× 1 0 4 L· mol- 1· cm- 1 ,铜量在0 - 2 0 μg/ 2 5 m L范围内遵守比耳定律。方法用于水样中微量铜的测定 ,结果满意。  相似文献   
28.
    
Abstract

Two new complexes, [Cu(SPPh3)3]2(PF6)2 (1) and [Ag2(SPPh3)2](PF6)2 (2), were prepared from [M(CH3CN)4](PF6)] (M = Cu and Ag) and triphenylphosphine sulfide ligand (SPPh3). The complexes have been characterized by elemental analysis, and UV-Vis and IR spectroscopies. Single-crystal X-ray structure analyses reveals that complexes 1 and 2 can both be described as a planar triangular configuration. Complex 1 is mononuclear and shows two crystallographically independent and chemically identical [Cu(SPPh3)3]+ cations. In binuclear complex 2, the sulfur atoms in SPPh3 adopt two different coordination modes, namely monodentate and monoatomic bridging. Luminescence properties investigation in solid state show that complex 1 revealed only one emission band at 471 nm (λex = 310 nm), which may be attributed to metal-to-ligand charge-transfer [MLCT]. However, complex 2 had two emission peaks which attributed to π–π* and n–π* transitions. Electrochemical experiment illustrated the complexes 1 and 2 represent irreversible Cu+/Cu2+ or Ag+/Ag pairs, respectively. In vitro antioxidant tests showed that the complex 2 had significant antioxidant activity against hydroxyl radicals.  相似文献   
29.
火焰原子吸收法测定氧化钼中铜、铅   总被引:2,自引:0,他引:2  
本文介绍了用火焰原子吸收法测定氧化钼中铜、铅的方法,确定了两种元素最佳仪器工作条件,该方法快速、简便、准确,对试样的回收为98.8-102%,样品测定的相对偏差小于1%,对实际样品了测定获得满意结果。  相似文献   
30.
本文利用吸附有双硫腙的微晶萘作富集柱富集天然水中痕量铜,甲酰二甲胺洗脱,火焰原子吸收光谱法测定。对最佳吸附酸度,过柱流速,洗脱剂,共存离子干扰等进行了探讨。该方法的相对标准偏差为2.3%,加标回收率为96%~103%。通过对国家标准水样及实际天然水样的分析测定,结果令人满意。  相似文献   
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