关于Mo-Fe-S原子簇化合物中硫的测定已经有些报道。为了同其中的钼铁含量的测定相配合,这里报道一种通过铬含量的原子吸收测定,而间接测定硫的方法。准确称取待测样品5—7mg,置于小烧杯中,加入1ml浓硝酸,盖上表面皿,氧化一会,再放到电炉上加热,使样品充分消解氧化,待溶液呈淡黄透明状取下(不能蒸干)。冷后加入少许水,滴入一滴0.2％的溴甲酚紫指示剂,再 The determination of sulfur in Mo-Fe-S cluster compounds has been reported. In order to be compatible with the determination of the molybdenum content therein, an indirect method for the determination of sulfur is reported here by atomic absorption spectrometry of the chromium content. Accurately weighed sample 5-7mg, placed in a small beaker, add 1ml of concentrated nitric acid, cover the surface of the dish, oxidation for a while, and then heated to the electric furnace, the sample was fully digested oxidation until the solution was pale yellow transparent Remove (can not be evaporated to dryness). Add a little water after cold, drop a drop of 0.2% bromocresol purple indicator, and then