【摘要】 分析了丁二酮肟光度法测定镍含量的机理和最佳条件,通过不同加入顺序的吸收曲线对比,探讨了试剂加入顺序对测定的影响。镍的测定是Ni2+在碱性条件下先与丁二酮肟显色形成络合物,然后再被氧化,补充碱可以使显色更完全。试剂加入顺序为镍溶液、丁二酮肟、过硫酸铵、氢氧化钠。在pH>12介质中,显色25 min,在470 nm波长处测定吸光度,其标准曲线在0-4μg.mL-1符合Beer定律,相关系数0.999 9。更多还原

【Abstract】 Content of nickel was measured by dimethyl glyoxime-spectrophotometry,and effect of reagents sequence was discussed via comparing absorption spectra.Principle and best conditions of this method were studied.Mensuration was carried out by this means: Ni2+ cations formed complex compound with dimethyl glyoxime and then oxiadted.Addition of alkali could make color fuller.Addition sequence was nickel solution,dimethyl glyoxime,ammonium persulfate,NaOH.Following such a sequence,standard curve agreed with Beer rule in the range of 0-4μg·mL-1 which was colored for 25min in the pH>12 solution and correlation factor of 0.999 9.更多还原