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Richard Essex

Publications

Preparation and calibration of a Protactinium-231 reference material

Author(s)
Richard M. Essex, Ross W. Williams, Kerri C. Treinen, Ronald Colle, Ryan P. Fitzgerald, Raphael Galea, John Keightley, Jerome J. LaRosa, Lizbeth Laureano-Perez, Svetlana Nour, Leticia S. Pibida
A 231Pa reference material has been characterized for amount of Pa. This reference material is primarily intended for calibration of 233Pa tracers produced for

New determination of the 229Th half-life

Author(s)
Richard M. Essex, Jacqueline L. Mann, Ronald Colle, Lizbeth Laureano-Perez, Megan E. Bennett, Heather Dion, Ryan P. Fitzgerald, Amy M. Gaffney, Amelie Hubert, Rob Steiner, Ross W. Williams, Alkiviadis Gourgiotis, William S. Kinman
A new determination of the 229Th half-life was made based on measurements of the 229Th massic activity of a high-purity solution for which the 229Th molality

New thorium-229 standard reference material

Author(s)
Richard M. Essex, Jacqueline L. Mann, Ross W. Williams, William S. Kinman, Amelie Hubert, Megan E. Bennett
A new reference material, preliminarily designated as SRM 3059, was characterized for 229Th molality (mol•g-1) and thorium isotope amount ratios. This SRM is
Created May 21, 2019