以正交试验设计法研究并得到了二安替比林 - (2 -羟基 ) -苯基甲烷试剂吸光光度法测定微量铬的最佳显色条件 ,其最大吸收波长为 480 nm。 Cr( )在 0 .10～ 10μg· 2 5 m L- 1 范围内呈良好线性关系 ,线性回归方程为A=0 .0 5 83C+0 .0 478,线性相关系数为 0 .9971,摩尔吸光系数ε=1.37× 10 5(L· mo L- 1 · cm- 1 )。灵敏度比文献报道有较大提高。方法应用于水样中铬 ( )的测定 ,结果满意 The optimum conditions for the determination of trace chromium with diantipyryl - (2 - hydroxy) - phenylmethane reagent spectrophotometry were studied by orthogonal experimental design and the maximum absorption wavelength was 480 nm. Cr () showed a good linear relationship in the range of 0 .10 ~ 10μg · 2 5 m L -1. The linear regression equation was A = 0.0583C + 0.047, the linear correlation coefficient was 0.9971, and the molar absorptivity The coefficient ε = 1.37 × 10 5 (L · mo L- 1 · cm -1). Sensitivity than the literature has greatly increased. The method was applied to the determination of chromium in water samples with satisfactory results