【摘要】 <正> 表面活性剂有阳离子型、阴离子型、非离子型和两性型等。已知的品种虽为数不少,但在分析化学中作为显色反应增敏剂研究较多的还是阳离子表面活性剂。而对阳离子表面活性剂的碳链长短和增敏效应的关系的研究仍未见报导。目前研究和应用最多的是溴(或氯)化十六烷基三甲铵、溴(或氯)化十六烷基吡啶、氯化十四烷基二甲基苄基铵等为数不多的几个品种。由于这些阳离子表面活性剂在水中的溶解度不大,故给工作带来不便,特别是在冬季。因此,我们结合稀土-铬天青S(CAS)-2,2′-联吡啶(dipy)-阳离子表面活性剂四元体系研究了卤代烷基吡啶系列中主碳链长短的影响,发更多还原

【Abstract】 A very sensitive colour reaction of rare earth elements with chromazurol S（CAS）, 2,2-dipyridine（dipy）, and dodecylpyridinium chloride（DPC） has been investigated. At pH 9.5～11.5 rare earth elements formed green quaternary complexes with the titled reagents exhibiting maxima absorption at wavelength 636～640nm. The apparent molar absorption coefficients were （1.08～2.23）·10⁵ 1· mol^-1·cm^-1. Beer’s law was obeyed for lanthanum in the range of 2.5～25μg/25ml, and for gadolinium 2.5～20μg/25ml. The effects of many foreign ions have been studied. A spectrophotometric method has been developed for the determination of lanthanum and gadolinium simultaneously in the presence of each other. The composition of the quaternary complex of lutetium was found as Lu:CAS:dipy:DPC=1:2:1:4.更多还原