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31.
无机离子交换剂以其选择性、耐热及抗辐照性很高一直受到重视.但由于它的交换过程缓慢,使其应用受到了限制,为了克服这一障碍,本文把十分之几微米的无机离子交换剂[Ti(HPO_4)_2·1/2H_2O]微晶粘结成球,以减低对流体阻力,同时大大增加交换表面.用这种交换剂研究了H~+-Li~+和Li~+-H~+互交换的动力学;同时,根据交换剂的几何模型,解出了相应界面条件的扩散方程.实验显示了在这种无机离子交换剂中的交换速度比在001×20的聚苯乙烯凝胶磺酸型阳离子交换树脂中的快3.5倍,它可能为提高无机离子交换剂的传质功能提供了新途径. 相似文献
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在60℃和恒定离子强度下,用平衡pH法研究顺丁烯二酸存在下Cr^3^+的水解和聚合作用.Cr^3^+和顺丁烯二酸同时以三种不同的浓度0.006,0.008和0.01mol.dm^-^3存在,Cr^3^+在水溶液中的状态用作图法和pqr分析法测定,发现有如下粒子存在:[CrA]^+,[Cr(OH)A],[Cr~2(OH)~2A~3].作图法的结果用计算机进行修正,计算了约50个数据点.所有粒子的水解常数均得到了良好的拟合.结果表明,使用LEMIT程序计算能比作图法所得的结果更为精确,此外还讨论了在顺丁烯二酸存在下Cr^3^+的聚合机理. 相似文献
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The interference of lanthanum in the spectrophotometric determination of yttrium in the form of β-type complex with chlorophosphonazo III (CPA III) is proved to be a cocoloration effect. It is due to the formation of a mixed polynuclear complex between CPA III and lanthahum-yttrium with a cyclic structure. The composition of the complex has been established to be La:CPA III:Y = 1:2:1 by the method of molar ratio. The optimal conditions for the formation of polynuclear complex and influence factors have also been studied. A "replacement type" reaction is proposed to account for the cocoloration effect. 相似文献
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The stability constants of complexes of N-phenylthiourea with bismuth (III) in 1M perchloric acid have been studied spectrophotemetrically by the method of corresponding solutions. The enthalpy change ΔH5^0 is obtained from the temperature coefficient data. The Gibbs free energy changes ΔG5^0 and the entropy changes ΔS5^0 are calculated from known formulas respectively. The experimental results are discussed. The successive accumulative stability constants and thermodynamic parameters ΔH5^0, ΔG5^0, ΔS5^0 are listed in Table 6 of the Chinese Text. 相似文献
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With mercury (II)-methyl thymol blue-X (SCN, Br, I) as example, two methods are investigated in this paper. The first one bases on the variation experimental design, so that classical method of degree of dissociation can be used to calculate the stability constant from the molar ratio curve obtained. This method is simple, adaptable to cases where the decomposition is relatively weak. The second method requires the preliminary acquisition of the equilibrium constant of the decomposition reaction, with the calculation of the stability constant of the preceding formation reaction thereon. The evaluation procedure is more strict. Thhis method is applicable whether the decomposition reaction is strong or weak. Thus, we obtain stability constants of ternary complexes with rather strong subsequent decomposition reaction, such as Hg.MTB.I. Results obtained are rather satisfactory. 相似文献
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