作者发现在酸性条件下微量Os(Ⅳ )对溴酸钾氧化对碘偶氮氯膦而使其退色的反应有显著的催化作用 ,据此提出一种在水相中直接测定微量Os的催化动力学分光光度新方法。方法检出限可达 0 0 0 1μg/ml,Os含量在 0 0 0 1～ 0 0 0 9μg/ml符合朗伯—比尔定律。方法简单、快速、灵敏度高 ,已用于贵金属合成样中痕量Os的测定 The authors found that the catalytic effect of trace amounts of Os (IV) on the oxidation of iodohydrochlorophosphonazo to fade of trace potassium (II) under acidic conditions has a significant catalytic effect. According to this, a catalytic kinetic spectrophotometry for the direct determination of trace Os in aqueous phase New method of luminosity. The detection limit of the method was 0 0 0 1 μg / ml, and the Os content was in the range of 0 0 0 1 0 0 0 9 μg / ml according to Lambert-Beer’s law. The method is simple, rapid and sensitive. It has been applied to the determination of trace Os in precious metal samples