前言有关测定不同价态钒的方法已有报导,如用吡啶硫氰酸盐氯仿萃取V~(2+),或用容量法同时测定V~(3+)和V~(2+)及在不同介质中用分光光度法测定V~(2+)、V~(3+)、V~(4+)等,也有人研究过V~(4+)与亚硝基萘酚二磺酸钠反应生成螯合物的吸收光谱。本文工作主要是研究了用极谱法在三价钒、四价钒和五价钒同时存在下分别测定的方法,并试验选择了四价钒、三价钒 Preface The methods for the determination of vanadium in different valence states have been reported, such as the extraction of V 2+ with pyridine thiocyanate chloroform or the simultaneous determination of V 3+ and V 2+ by the volumetric method, V ~ (2 +), V ~ (3 +) and V ~ (4+) were determined by spectrophotometry in different media. Some studies have also reported that V ~ (4+) and nitroso naphthol disulfonate The absorption spectrum of the chelate produced by the reaction. The main work of this paper is to study the polarographic method in the presence of trivalent vanadium, tetravalent vanadium and pentavalent vanadium were determined separately, and the test selected tetravalent vanadium, trivalent vanadium