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A new highly enriched 233U reference material for improved simultaneous determination of uranium amount and isotope amount ratios in trace level samples
Published
Author(s)
Richard Essex, Ross W. Williams, Kayron T. Rogers, Cole R. Hexel, Tashi Parsons-Davis, Kerri C. Treinen
Abstract
A highly-enriched 233U reference material (>0.99987 n(233U)/n(U)) has been prepared and characterized for use as an isotope dilution mass spectrometry spike. An ion exchange separation was performed on 1 gram of high purity 233U to further reduce trace amounts contaminant Pu in the material. The purified 233U was then prepared as a master solution which was analyzed for molality of uranium by modified Davies and Gray titration. A portion of the master solution was quantitatively diluted and dispensed for reference material units. Selected units were analyzed to characterize uranium isotope amount ratios by multi-collector inductively couple plasma mass spectrometry and for verification of uranium content. Modelling of spike-corrected isotopic data show that the new spike will enable simultaneous measurements of uranium amount and isotope amount ratios with resulting uncertainties that are substantially less sensitive to over spiking than widely used 233U certified reference materials.
Essex, R.
, Williams, R.
, Rogers, K.
, Hexel, C.
, Parsons-Davis, T.
and Treinen, K.
(2021),
A new highly enriched 233U reference material for improved simultaneous determination of uranium amount and isotope amount ratios in trace level samples, Talanta, [online], https://doi.org/10.1016/j.talanta.2020.121638, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=930532
(Accessed October 10, 2025)