研究了新显色剂DBC—偶氮胂与铋的显色反应。该试剂及其与铋的络合物的最大吸收波长分别为528nm及632nm,络合物的表观摩尔吸光系数为9.0×10~4升·摩尔~(-1)·厘米~(-1)。在1.2N高氯酸介质中,大量的常见离子均不干扰铋的测定。若使用加入过量溴离子的褪色溶液作为参比,可以不经分离直接测定纯铜,铜合金及人发中的痕量铋,方法快速、简便、准确。七次测定的变动系数为2.4%。 The color reaction of DBC-arsenazo with bismuth was studied. The maximum absorption wavelength of this reagent and its complex with bismuth was 528 nm and 632 nm, respectively. The apparent molar absorptivity of the complex was 9.0 × 10-4 mol · cm -1. . In 1.2N perchloric acid medium, a large number of common ions do not interfere with the determination of bismuth. If the use of excess bromide ion fading solution as a reference, can be directly measured without isolation of pure copper, copper alloy and human hair trace of bismuth, the method is fast, simple and accurate. The coefficient of variation for the seven determinations was 2.4%.