【摘要】 研究５－Ｂｒ－ＰＡＤＮ与铁（Ⅲ）的显色反应，在ｐＨ９．０～９．４范围内，当有１０％ＳＤＳ存在时，铁（Ⅲ）与５－Ｂｒ－ＰＡＤＮ形成１：４的稳定配合物。λ＿（ｍａｘ）为５３４ｎｍ，ε为５．１３×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），铁（Ⅲ）浓度在０～１２．５×１０￣（－４）ｇ／Ｌ范围内符合Ｂｅｅｒ定律，用双峰双波长法测定茶叶中痕量铁（Ⅲ），结果满意。更多还原

【Abstract】 In the range of pH 9.0～9.4 and with 10%of SDS, iron（Ⅲ）reacts with5-Br-PADN to form a stable complex at the proportion of one to four. Its λ_max is 534 nm, and εis 5.13×10￣4L·mol￣（-1）·cm￣（-1）,The Beer’s law is obeyed in the range of 0 to 12.5×10￣（-4）g/L of iron（Ⅲ）density. This method is used to determine trace iron（Ⅲ）in tealeaves and the result is satisfactory.更多还原