地质样品经硝酸-氢氟酸-高氯酸密闭分解。适当稀释样品(稀释因子DF=1 000),控制试液中的含盐量,并结合内标(Rh、Ir)校正消除基体效应和物理效应。28Si16O1H、29Si16O干扰45Sc的测定,在样品处理时除硅以消除其干扰。142Ce2+、142Nd2+干扰71Ga的测定,58Ni16O、148Sm2+、148Nd2+干扰74Ge的测定,114Sn、98Mo16O、97Mo16O1H干扰114Cd的测定,115Sn、98Mo16O1H、98Mo17O干扰115In的测定,采用数学校正法消除它们的干扰。高含量的204Pb和206Pb分别干扰203Tl和205Tl的测定,在样品处理时采用沉淀分离铅以消除其干扰。应用此方法测定了国家一级标准物质中的钪、镓、锗、铟、镉和铊的含量,测定值与认定值相符。

Geological sample was decomposed with a mixed acid of nitric acid, hydrofluoric acid and perchloric acid under hermetic condition. The salt content of the sample solution was carefully controlled by appropriate dilution with value of DF of 1 000. Elimination of matrix and physical effects were attained by correction with Rh and Ir as internal standards. Interferences of 28Si16O1H and 29Si16O on the determination of 45Sc were eliminated by removal of Si in sample pre-treatment. Furthermore, some other interferences, such as 142Ce2+ and 142Nd2+ on the determination of 71Ga, 58Ni16O, 148Sm2+ and 148Nd2+ on the determination of 74Ge, 114Sn, 98Mo16O and 97Mo16O1H on the determination of 114Cd, 115Sn, 98Mo16O1H and 98Mo17O on the determination of 115In, were eliminated by mathematical corrections. The interferences of 204Pb and 206Pb (with high concentration) on the determination of 203Tl and 205Tl were eliminated by separation with precipitation of Pb from the sample solution in the pre-treatment. The proposed method was tested by analyzing a CRM for its corrtents of Sc, Ga, Ge, In, Cd and Tl, giving results in consistency with the certified values.