摘要
试验了Cr(Ⅵ)与对氨基二甲基苯胺氧化显色反应的条件。试验结果表明,Cr(Ⅵ)与对氨基二甲基苯胺反应形成的红色产物在554nm处有最大吸收,表观摩尔吸收系数为3.4×10~4L·mol^(-1)·cm^(-1),线性范围为0～1.6μg·ml^(-1)。采用全差示光度法测定脱脂奶粉中的总铬,用于某脱脂奶粉中0.23mg·kg^(-1)的铬测定时,相对标准偏差为3.7％(n=6)。测定结果与AAS法相比令人满意。
The oxidation color reaction of Cr(VI) with p-amino-N, N-dimethylaniline was studied and reported in this paper. It is found that Cr( VI ) reacts with the above mentioned reagent to form a red oxidized product in the presence of alcohol. Its apparent molar absorptivity is 3. 4×10~4L ·mol^(-1) ·cm^(-1) at 554nm. Beer's law is obeyed in the range of Cr( VI ) 0~1. 6μg ·ml^(-1). The proposed method has been used for the determination of Cr in defatted milk powder by completely differential spectrophotometric method. The analytical results indicate a precision of 3. 7% (n = 6) for the determination of 0. 23mg ·kg^(-1) Cr. The results obtained are in good agreement with those of AAS method.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
1999年第4期170-171,共2页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
关键词
铬
对氨基二甲基
苯胺
全差示光度法
显色反应
Chromium, p-Amino-N, N-dimethylaniline, Completely differential spectrophotometric method, Defatted milk powder
