The concentrations of chromic anhydride, nitric acid and potassium permanganate in chromating bath were determined by ridge regression spectrophotometry.

• 采用岭回归法同时测定镀锌钝化液中铬酐、硝酸、高锰酸钾等3组分的浓度,样品不经分离,不需加任何试剂。