摘要
在0.2mol·L-1H2SO4介质中,偶氮氯膦 DBC(CPA DBC)与铬(Ⅵ)发生氧化褪色反应,该褪色反应的表观摩尔吸光系数ε550=2.35×104L·mol-1·cm-1,铬(Ⅵ)在0.040～0.60μg·ml-1范围内与吸光度差值呈良好线性关系。方法用于芹菜、大米、面粉中铬分析,结果满意。
In a dilute acidic medium of c(H2SO4) 0.10～0.72mol·L^(-1), CPA-DBC is oxidized by (Cr(Ⅵ)), leading to a fading of the color reagent. The decrease of color intensity (ΔA) of CPA-DBC was found to have a linear relationship with the concentration of Cr(Ⅵ) in the range from 0.040 to 0.60μg·ml^(-1) and the apparent molar absorptivity (ε) was found to be 2.35×10~4L·mol^(-1)·cm^(-1) at 550nm which is the absorption maximum of CPA-DBC. This method has been applied to the determination of microamounts of Cr(Ⅵ) in celery, rice, and wheat flour with satisfactory results.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2004年第11期638-639,共2页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
关键词
褪色光度法
铬(Ⅵ)
偶氮氯膦—DBC
芹菜
大米
面粉
Photometry
Chromium(Ⅵ)
CPA-DBC
Oxidation-color-fading reaction
Celery
Rice
Wheat flour
