Thermal Ionization Mass Spectrometry Measurements of Ra-226 and U Isotopes in Soils, Surface and Groundwaters: Analytical Aspects and Pore Water-Matrix Interactions Revisited

摘要

Recent developments in thermal ionization mass spectrometry and in the chemical separation of Ra and Ba through cation exchange chromatography now allow the analysis of ~(226)Ra and U isotopes (~(234)U, ~(238)U) in smaller samples than those required using conventional counting techniques. Routine measurements are now obtained with picogramme (U) to subpicogramme (Ra) quantities of these elements (i.e. in water samples of a few millilitres for U isotopes, and of <=200 mL for ~(226)Ra. Details are given on the analytical procedures used for ~(226)Ra measurements in low mineralized waters.