叙述了准确测定铀矿石中2 3 0 Th比活度的新方法 ,该法提出在样品中加入2 3 0 Th /2 3 2 Th活度比小的标准稀释剂 ( 2 3 2 Th比活度和2 3 0 Th/2 3 2 Th活度比已知 ) ,采用活度比稀释法进行测定 .该方法不仅适用于在各种2 3 0 Th/2 3 2 Th活度比样品中准确测定2 3 0 Th比活度 ,而且明显提高铀矿石中2 3 0 Th比活度的测量精度 . A new method for accurately determining the specific activity of 2 3 0 Th in uranium ores was described. The method proposed adding a standard diluent with a low activity ratio of 230 Th / 2 3 2 Th (2 3 2 Th specific activity And the activity ratio of 2 3 0 Th / 2 3 2 Th is known), and this method is not only suitable for the accurate determination of various activity ratios of 2 30 Th / 2 3 2 Th 2 3 0 Th specific activity, but also significantly improve the measurement accuracy of 2 3 0 Th specific activity in uranium ores.