摘要
本文以pH电位法系统地研究了钇与八种不同结构的α-氨基酸的配位作用。这八种氨基酸为DL-α-氨基丙酸,L-丝氨酸,L-苏氨酸、L-半胱氨酸、L-天冬氨酸,L-天冬酰胺、L-谷氨酸及L-组氨酸。在30.0±0.1℃及离子强度μ=0.10M(NaClO_4)的条件下,测定了各氨基酸的质子化常数及这些氨基酸与钇的配合物稳定常数。后者数据多数未见文献报导。同时,着重研究了组氨酸与十四种稀土元素的成配规律,见到有明显的“钆断效应”及不甚显著的“四分组效应”。提供了重稀土元素与组氨酸配合物稳合常数的新数据。文中讨论了不同取代基团对氨基酸配合物稳定性的影响,钇在镧系元素中的位置及稀土氨基酸的成配规律。
In the present work, the complexation of yttrium with eight a-amino acids: DL-alanine, L-serine, L-threonine, L-cysteine, L-asparagine, L-aspartic acid, L-glutaminic acid and histidine were investigated. Protonation constants of these a-amino acids and stability constants of above complexes were determined potentiometrically at 30. 0 ±0.1℃ and ionic strength of 0.1.Most of the stability constants have not yet been reported in the literature. The stability constants of the complexes of 14 rare earth elements with histidine also had been reported. The data of heavy rare earth elements were repored first time.Obvious 'gadolinium break effect' and slight 'tetrad effect' appeared in these systems.All the calculations were performed by computer.
基金
国家自然科学基金
关键词
稀土元素
Α-氨基酸
络合物
Rare earth elements, Lanthanide, Complexes, α-Amino acid.
