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Richard Essex, Jacqueline L. Mann, Ross W. Williams, William S. Kinman, Amelie Hubert, Megan E. Bennett
Abstract
A new reference material, preliminarily designated as SRM 3059, was characterized for 229Th molality (molg-1) and thorium isotope amount ratios. This SRM is intended for use in nuclear forensic analyses as an isotope dilution mass spectrometry spike. The value and expanded uncertainty (k = 2) for the 229Th molality is (1.1498 ± 0.0016) 10-10 mol g-1 solution. The values and expanded uncertainty (k = 2) for the n(230Th)/n(229Th) ratio is (5.18 ± 0.26) 10-5 and the n(232Th)/n(229Th) ratio is (3.815 ± 0.092) 10-4.
Essex, R.
, Mann, J.
, Williams, R.
, Kinman, W.
, Hubert, A.
and Bennett, M.
(2017),
New thorium-229 standard reference material, Applied Radiation and Isotopes, [online], https://doi.org/10.1016/j.apradiso.2017.07.050
(Accessed October 9, 2025)