缝管原子捕集方法研究

An Investigation of Slotted Quartz Tube Atom-Trapping tomic Absorption Spectrometry

试验了各种条件对Ｂｉ、Ｇａ、Ｓｂ灵敏度影响。结果表明，分别用不同的火焰条件进行原子捕杀与放可获得最佳灵敏度。捕集１ｍｉｎ，测得Ｂｉ、Ｇａ、Ｓｂ的特征浓度依次为３．５×１０－３、１．６×１０－３、１．８×１０－３μｇ·ｍｌ－１，它比常规火焰原子吸收光谱法的灵敏度分别提高２５４、１３１、２３９倍。Ｂｉ、Ｇａ、Ｓｂ的变异系数各为２．９、３．５、４．７％。本法测定了纯锡中微量Ｂｉ、Ｓｂ。

The effects of various conditions on the sensitivities of Bi, Ga, Sb were investigated.The results show that the best sensitivity is obtained when different flame conditions are used for collection and release respectively. The characteristic concentration obtained after trapping for 1 min are: Bi 3. 5×10-3, Ga 1. 6× 10-2, Sb 1, 8× 10-3μg·mL-1. Thus slotted quartz tube atom -trapping AAS Yields increases in sensitivity for Bi, Ga, Sb of 254, 131, 239 fold respectively,in comparison to the conventional FAAS. The coefficients of variation are: Bi 2. 9, Ga 3. 5, Sb 4.7%. The Bi and Sb in pure tin have been determined.