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研究了新显色剂二溴羟基苯基荧光酮（ＤＢＨＰＦ）在阳离子表面活性剂溴化十六烷基三甲基铵（ＣＴＭＡＢ）存在下与铋的显色反应。在ｐＨ６．４～６．７的六次甲基四胺─盐酸缓冲介质中，Ｂｉ（Ⅲ）与ＤＢＨＰＦ反应生成组成比为１：２的水溶性和稳定性皆佳的紫蓝色络合物，其吸收峰波长λｍａｘ＝６０２ｎｍ，对比度（△λ＝８２ｎｍ表现摩尔吸光系数ε６０２＝５．３６×１０４Ｌ·ｍｏｌ－１·ｃｍ－１。Ｓａｎｄｅｌｌ灵敏度是３．９０×１０－３μｇ·ｃｍ－２，Ｂｉ（Ⅲ）浓度为０～１５．０μｇ／１０ｍｌ时服从比尔定律，其检测下限是０．２１μｇ／１０ｍｌ。采用巯基棉分离，能够消除许多金属离子的干扰。本方法用于焊锡和铸造锡合金中微量铋的测定，结果较满意。
The color reaction of dibromohydroxyphenylfluorone (DBHPF) with bismuth in the presence of cationic surfactant cetyltrimethylammonium bromide (CTMAB) was studied. Bi (Ⅲ) reacts with DBHPF in a pH 6.8 ~ 6.7 hexamethylenetetramine-HCl buffer medium to form a violet-blue complex with a water-soluble and stable composition ratio of 1: 2 , The absorption peak wavelength λmax = 602nm, the contrast (Δλ = 82nm, the molar absorption coefficient ε602 = 5.36 × 104L · mol-1 · cm-1.Sandell sensitivity was 3.90 × 10-3μg · cm-2, Beer’s law is obeyed when the concentration of Bi (Ⅲ) is 0-15.0μg / 10ml, and the detection limit is 0.21μg / 10ml. The separation of thiol cotton can eliminate the interference of many metal ions. This method is used for the solder and cast tin alloys Determination of trace bismuth, the results are more satisfactory.