Electrochemical properties of modified copper-thallium hexacyanoferrate electrode in the presence of different univalent cations

The preparation of copper(II) hexacyanoferrate (CuHCF) films on the surface of gold electrodes as well as their characterization in solutions of various alkali metal and NH₄⁺ cations and in the presence of thallium(I) are described. The electrochemical quartz crystal microbalance and cyclic voltammetric techniques were used. In 0.50 M lithium nitrate, even at submillimolar concentration of Tl(I), the formal potential of CuHCF was shifted to more positive values. At higher Tl(I) concentrations, the formal potential of the CuHCF redox reaction changed linearly with the logarithm of Tl(I) concentration (in the 0.50 M solution of lithium or another alkali metal nitrate). From such dependencies, selectivity coefficients K_Tl/M were calculated, and they show that the CuHCF film on the gold electrode interacts preferentially with Tl(I). High affinity of Tl(I) to copper hexacyanoferrate, that was observed in the presence of alkali metal cations, was explained by relatively strong donor-acceptor interactions of Tl(I) ions with nitrogen in CN groups of the CuHCF film.It was also shown for simple M₄[Fe(CN)₆] metal ferrocyanate salts (where M = Li⁺, Na⁺, K⁺, Rb⁺, Cs⁺ and Tl⁺) that there is a preferential interaction of Tl⁺ with CN group consistent with formation of a Tl-NC-Fe bridge.     

含镉铊物料中组元镉和铊活度系数的测定研究

在400～700℃范围和10～60Pa条件下进行真空蒸馏含镉和铊等元素物料的实验,通过测定镉和铊的化学成分,计算组元的活度系数,并用最小二乘法拟合实验数据,得到镉与铊活度系数与温度、成分关系以及活度系数与温度及成分之间的关系,为真空冶金蒸馏法获取镉和铊材料提供理论依据．     

Obtaining of high surface roughness copper deposits by electroless plating technique

The use of pyridine-2,6-dicarboxylic and 4-hydroxypyridine-2,6-dicarboxylic acids as copper(II) ligands in formaldehyde-containing alkaline electroless copper plating solutions allowed to obtain copper layers with extremely high surface roughness factor reaching approximately 120. The Cu deposits of higher surface area were formed at highly negative open-circuit (mixed) potentials; the correlation between copper electrode overpotential and roughness of the deposit was found and discussed. The copper films obtained demonstrate a high electrocatalytic activity in anodic formaldehyde oxidation process, the oxidation rate reaches 40 mA cm⁻² and exceeds considerably that for other copper surfaces.     

Growth of Tl-2201 Superconducting Thin Films on Single Crystal LaAlO3

The growth of Tl-2201 films on LaAlO₃ single crystal substrates has been investigated. The synthesis involved precursor films made by laser ablation that were treated with Tl₂O(g) in near-equilibrium conditions. By optimising the method of preparation, we obtained films that were highly smooth, c-axis oriented and epitaxial. The rocking curve of the (0010) reflection had a FWHM of 0.27°. A T_c of 92K was achieved without post-annealing.     

Synthesis and Properties of Molybdotungstogallic Heteropoly Complexes

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山东乳山金矿区及外围铊地球化学找矿矿究

在探讨铊地球化学异常原理的基础上,分析了利用铊地球化学异常方法找矿的研究现状,对乳山金矿已知矿体及其外围进行了铊土壤分析,根据铊异常提出了新的成矿预测靶区。     

碘化物-乙基紫-阿拉伯胶体系高灵敏分光光度法测定铊

基于Ｔｌ（Ⅲ）与碘化物和乙基紫在阿拉伯树胶存在下形成离子缔合物的显色反应，建立了高灵敏分光光度测定铊的分析方法。     

铊污染的危害特性及防治

文章介绍了铊的来源、危害及迁移方式,对目前铊污染的防治技术的研究现状进行了介绍,分析了化学法、物理法、生物法的原理和技术要点,提高群众对铊污染的认识和对其治理技术的了解.     

石墨炉原子吸收光谱法测定水中的铍

采用石墨管涂层处理技术,在对几种基体改进剂的改进作用进行试验比较的基础上,选择Pd-Mg(NO3)2(3% Pd ～2% Mg)为基体改进剂,对水中的铍进行了测定,并应用此方法对葫芦岛造船厂和平山水源的水样进行了加标回收实验,取得了较为满意的结果.