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Jacqueline L. Mann (Fed)

Jacqueline's employment at NIST began with the measurement of sulfur concentration by isotope dilution thermal ionization for certification of fossil fuel (coal, diesel fuel, fly ash, gasoline, etc.) and other Standard Reference Materials (SRMs).  This activity evolved into the development of a high-precision technique for the measurement of sulfur isotope composition of these and other environmental materials with sub-micromolar quantities of sulfur. More recently, measurements of moisture and other additional analytes including chlorine and mercury have been a part of her activities. Currently, she is also actively involved with learning new analytical techniques for isotopic measurements associated with the NIST Isotopic Reference Material Program. She has authored or co-authored 13 peer-reviewed publications describing these activities.


  • NSF Office of Polar Programs Postdoctoral Fellowship (2006, declined)
  • Best Talk Award (Ph.D. Category), University of Maryland
  • EPA STAR Fellowship (1998-2001)
  • GSA Grant 2001
  • Sigma Xi Grants 1995 and 2001

Membership and Professional Activities:

  • American Geophysical Union
  • Geological Society of America
  • ASTM


New determination of the 229Th half-life

Richard Essex, Jacqueline L. Mann, Ronald Colle, Lizbeth Laureano-Perez, Megan E. Bennett, Heather Dion, Ryan P. Fitzgerald, Amy M. Gaffney, Amelie Hubert, Robert E. 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

Richard 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 October 9, 2019, Updated December 8, 2022