用液体闪烁计数法测定含铀、钚体系中的^（99）Tc

DETERMINATION OF 99Tc IN UO2(N03)2-Pu(NO3)4-HNO3 BY LIQUID SCINTILLATION COUNTING

建立了一个在含铀、钚的硝酸体系中测定９９Ｔｃ的液体闪烁分析法。研究了取样体积、闪烁液用量、硝酸加入量、铀加入量、钚加入量等因素对９９Ｔｃ测定的影响。此外还对用２，６－二甲基吡啶从碱性介质中分离纯化９９Ｔｃ，以及自ＴＢＰ中用ＣＣｌ４稀释、用水反萃９９Ｔｃ进行了研究。给出了用２，６－二甲基吡啶萃取－液闪测量９９Ｔｃ的操作程序。此方法测定结果的单值相对标准偏差为０．６％。用该程序分析了各种工艺实验样品中９９Ｔｃ含量，获得了满意的结果。

The determination of￣(99)Tc in a system of UO2(NO3)2 -Pu(NO3)4 and HNO3 by a liquid scintillation counting is developed.The effects of sample volume,amount of scintillation cocktail,nitric acid, uranium and plutonium on the determination of 99Tc have been investigated.The isolation and purification of 99Tc using 2,6-dimethyl pyridine extraction from alkaline medium followed the stripping of 99Tc from 30%TBP-kerosene loaded with ￣(99)Tc using CCl4 as diluent have also been studied.A determination procedure of ￣(99)Tc by the liquid scintillation counting with 2,6-dimethyl pyridine extraction is recommended.The relative standard deviation for the determination of ￣99Tc using this procedure is 0.6%. The procedure has been adapted to the samples containing uranium,plutonium and ￣99Tc. The experimental results show that the analytical procedure for determining￣(99)Tc is satisfactory.