美国陆军法兰克福兵工厂采用碘化钾和次磷酸钠混合试剂分光光度法测铜中的铋,精确度好,回收率高。商业铜中的铋最多不应超过0.001％或0.003％,药筒用黄铜中的铋不应超过0.006％,否则就会影响材料的物理性能。因此该厂改进了测定铜和黄铜中痕量铋的方法,即先用氢氧化铵共沉淀铋,然后用混合试剂测 US Army Frankfurt Arsenal using potassium iodide and sodium hypophosphite mixed reagent spectrophotometry of copper in the bismuth, good accuracy, high recovery. Bismuth in commercial copper should not exceed 0.001% or 0.003% at most, and bismuth in the brass for the cartridge should not exceed 0.006%, otherwise the physical properties of the material will be affected. Therefore, the factory has improved the method for the determination of trace amounts of bismuth in copper and brass by first coprecipitating bismuth with ammonium hydroxide and then measuring