Measurement of ⁶³Ni in Concrete Samples in Reactor

In order to develop a new method of measuring ⁶³Ni in concrete samples of reactor, these study were done, including the ways of dissolving the samples, drawing the elution curve, the measurement efficiency, recovery tests, decontamination experiments and blank tests. Samples were ground to 0.074 mm and were pretreated before liquid scintillation counting(LSC) by leaching with mixed acid （V(HNO₃)∶V(HClO₄)∶V(HF)=3∶2∶1）, anion exchange, hydroxide precipitation, and solvent extraction. The chemical yield of this method is 73.05%, and the radiochemical yield of this method is 71.99%. The standard deviation is 0.200/s and the relatively standard deviation is 12.8%(n=12). The detection limit of the method is 3.596 Bq/g. This method can be applied to the routine and emergency monitoring for ⁶³Ni of the concrete materials in or not in the reactor.