Preparation and Certification of New Thorium Isotopic Reference Materials
Preparation of two Isotopic Reference Materials of thorium has been performed, starting from highly enriched (232)Th (99.99%) and (230)Th (99.8%). After full characterization (chemical and isotopic) of these purified base materials the thorium nitrate was transformed to thorium dioxide. Accurately weighed amounts of the two isotopes in the dioxide form were subsequently dissolved in nitric acid and resulted in solutions with amount ratios n(230TH)/(232Th) close to 10(-5) (IRMM-035) and 3 . 10(-6) (IRMM-036). These gravimetrically prepared ratios were finally verified by means of thermal Ionization Mass Spectrometry (TIMS). the purpose of the Reference Materials is to calibrate thorium isotope amount ratio measurements.
Bibliographic Reference: Article; Frsenius Journal of Analytical Chemistry 361(1998)5, 400-403
Record Number: 199910602 / Last updated on: 1999-04-01
Original language: en
Available languages: en