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报道了以５－（５－硝基－２－吡啶偶氮）－２，４－二氨基甲苯（５－ＮＯ２－ＰＡ－ＤＡＴ）为显色剂，应用双峰双波长光度法测定铜（Ⅰ）的新方法。实验结果表明，在ｐＨ４．０～ｐＨ６．０的乙酸－乙酸钠缓冲溶液中和盐酸羟胺和乙醇存在下，铜（Ⅰ）可与试剂形成稳定的１∶２红色配合物。其最大吸收峰为５１９ｎｍ，负峰为４３６ｎｍ。正负峰吸光度绝对值之和与铜（Ⅰ）浓度线性相关，铜的质量浓度在０～０．７μｇ／ｍＬ范围内符合比尔定律，表观摩尔吸光系数ε５１９，４３６高达１．５４×１０５Ｌ·ｍｏｌ－１·ｃｍ－１，ε５１９为６．７１×１０４Ｌ·ｍｏｌ－１·ｃｍ－１。已用于铝合金和纯铝中微量铜的直接测定，相对标准偏差＜０．４４％。
Reported the determination of copper (Ⅰ) with 5- (5-nitro-2-pyridylazo) -2,4-diaminotoluene (5-NO2-PA-DAT) ) Of the new method. The experimental results show that copper (Ⅰ) can form a stable 1: 2 red complex with the reagent in the presence of hydroxylamine hydrochloride and ethanol at pH 4.0 ~ pH 6.0 in acetic acid - sodium acetate buffer solution. The maximum absorption peak is 519nm, the negative peak is 436nm. The sum of the absolute values of positive and negative peak absorbances was linearly correlated with copper (Ⅰ) concentration. Beer ’s law was obeyed in the range of 0 ~ 0.7 μg / mL. The apparent molar absorptivity ε519, 436 was 1.54 × 105 L · mol-1 · cm-1, ε519 was 6.71 × 104L · mol-1 · cm-1. Has been used for direct determination of trace amounts of copper in aluminum and aluminum, the relative standard deviation of <0.44%.