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β2-Keggin结构稀土元素钨砷杂多配合物的合成与表征 总被引:1,自引:0,他引:1
采用直接法合成了8种稀土元素取代的钨砷杂多配合物,通过ICP和TG曲线确定了其化学式为K11[Ln(AsW11O39)2].xH2O,采用IR、UV、XRD1、83WNMR等方法对配合物结构进行了表征,结果表明合成配合物为β2-Keggin结构。TG-DTA分析对合成配合物的热稳定性考察表明,配合物在515~545℃分解。 相似文献
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R. Puthiyottil S. Varghese J. T. Guthrie 《Polymer-Plastics Technology and Engineering》2013,52(11):1111-1118
Europium-β-diketone chelate doped poly(methyl methacrylate) and poly(methyl methacrylate)/poly(ethylene co-vinyl acetate) blends have been successfully prepared and characterized. The mechanical properties of the PMMA-EVA systems have been assessed in terms of tensile strength and impact strength. The thermal characteristics and the energy involved in thermal decomposition have been studied. The structural properties of the complex doped polymeric systems reveal that the complex exists in the same crystalline state in the doped systems as it does in the pure state. The orientations of the groups in the host matrix have been found to be affected by the complex loading. The optical properties of the system have been studied by photo luminescence spectroscopy. The fluorescence lifetime have been observed to decrease at greater loadings of the complex; an effect that has been attributed to concentration quenching. The complex doped PMMA/EVA polymer network developed is considered to be a potential candidate for the development of optoelectronic devices those possess superior mechanical properties. 相似文献
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壳聚糖-分子筛复合物选择性吸附卷烟烟气中挥发性羰基化合物的应用研究 总被引:3,自引:0,他引:3
制备了壳聚糖-分子筛复合物,并使用扫描电镜观测了复合物的微观形态.研究了分别添加壳聚糖-分子筛复合物、4A分子筛及壳聚糖等材料的卷烟复合滤咀对主流烟气中低分子醛酮类化合物的吸附效果.研究结果表明,添加了壳聚糖-分子筛复合物、4A分子筛及壳聚糖的卷烟滤咀对主流烟气中低分子醛酮类化合物均有较好的吸附作用.且对焦油、烟碱量无明显影响;壳聚糖-分子筛复合物(添加量为2.4 mg·mm-1)对主流烟气中醛酮类化合物的吸附能力优于其它2种材料,该复合物对一氧化碳有一定的吸附,且对抽吸品质有改善,口感柔和,烟气刺激性降低. 相似文献
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To create a chemical-technological complex for the joint processing of cracked gases and pyrolysis gases, the technique of its design was developed. Based on the design capacity of the pyrolysis and cracking units, mass flows of cracked gases and pyrogas entering the chemical-technological complex have been calculated. A scheme has been developed for the proposed complex. To reduce the dimension of the design task, the whole complex was divided into a separate region. Based on the stoichiometric and kinetic models, the calculation of material balances for all processes included in the largest ethylene region has been carried out. The technological parameters were taken from the operated industrial units and processes on the stage of design. The industrial productivity of reactor elements by the targeted products has been determined. 相似文献
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《Carbon》1987,25(1):129-133
The adsorption of silver diammine complex on graphitized carbon black has been studied in aqueous ammonia solution. The carbon black has been gasified to various levels of burnoff in order to increase its active surface area (ASA). The effect of different parameters, ASA, concentrations of silver diammine and of ammonium cations on the silver adsorption has been investigated. The metal complex interacts specifically with the active sites located in the ASA where it undergoes a reduction to metallic silver. A phenomenological model of the adsorption and decomposition reactions of the silver complex is proposed. 相似文献
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The use of calcium hydroxide for decomposing chromium complex dyes in alkaline solution has been examined. Kinetic investigations have been carried out using chromium complex dyes of both 1:2 and 1:1 types, prepared by coupling 4-chlor-2-aminophenol-5-sulphonamide with 4-acetylamino-1-naphthol.The influence of the pH of the reaction solution, the temperature and the concentration of substrates on the course of the reaction and its yields has been observed.Kinetic investigations of the decomposition reactions of the dyes show their dependence on temperature; a rise of 10°C results in a fourfold increase in the rate constant.It has been found that the decomposition reaction of 1:1 chromium complex dyes is second order with respect to the dye, whereas decomposition of the 1:2 complex dyes occurs according to half-order reaction kinetics. 相似文献
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Cyclic voltammograms of hexaamminecobalt complex have been measured in high pH solutions. The spectroscopic result suggested that hydroamminecobalt complex adsorbed on the electrode surface during cathodic polarization, and this species grew to form cobalt hydroxide after a long time of electrolysis. In the anodic process, the reaction orders for pH and NH3 were both |1|. Based on these results, the reaction mechanism has been discussed.The effect of light on the electrode process has been studied by irradiating with ultraviolet light of the 254 nm mercury resonance line. It has been indicated that the hydroxoammine complex is decomposed to cobalt hydroxide and free ligand under light. 相似文献
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Successive differential sorptions have been measured for the system polyelectrolyte complex of poly(acrylic acid)/poly(4-vinylpyridine) + water vapor. The sorption data revealed that the sorption process of water vapor in the complex is controlled not only by diffusion mechanism but also by relaxation mechanism of polymer chains. It has been considered that the complex is composed of a loosely crosslinked, slightly ionized, and relatively homogeneous network structure. The sorption–desorption kinetics have also been investigated for the region of intermediate and high vapor pressures. The interval sorption–desorption curves demonstrated that the complex has the nature of the hysteresis effect in sorptions. It has been concluded that the appearance of sorption hysteresis is due to the depression of mobility of polymer chains resulting from crosslinks between carboxyl groups and pyridine rings. 相似文献