液闪法测定大体积样品水中氚

Determination of Tritium in Large Volume Sample by the Liquid Scintillation Method

介绍了液闪法测定水中氚过程,增加待测样品体积有效降低探测下限的方法。通过比对实验确定了100mL计数瓶测量方法的可行性,进一步对该方法的能量区间、样品与闪烁液配比、静置避光时间进行优化,对该方法的探测下限、准确度、精密度进行测试。结果表明,该测量方法的探测下限可低于0.4Bq/L,多组样品测试结果准确度范围为-6.58%〜5.01%,精密度范围为1.56%〜3.94%。该方法无需对水样做浓集前处理,即可实现对环境低水平氚的快速有效测量。

The method of increasing the volume of sample to be measured and decreasing the detection limit of tritium in water by liquid scintillation is introduced.The feasibility of the 100ml counting bottle measurement method was determined through comparison experiments,and the energy interval of liquid scintillation spectrometer,the ratio between sample and LSC cocktail,and the time to avoid light were optimized.The detection limit,accuracy and precision of the method were tested.The results show that the detection limit of the method can be lower than 0.4Bq/L,the accuracy range of the test results from multiple groups of samples is-6.58%~5.01%,and the precision range is 1.56%~3.94%.The method can measure the low level of tritium quickly and effectively without the need of concentration pretreatment.