Determination of specific activity of 230Th in uranium ore samples

A new method suitable for determining specific activity of230Th in uranium ore samples is built. The method is characterized by adding the230Th/232Th standard dilution agent with lower activity ratio (Its230Th/232Th activity ratio and230Th have been known) to the samples and using isotopic dilution analysis. The method can be applied to analyses of230Th specific activity in various230Th/232Th activity ratio samples. The precision can also be improved.