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Ronald Colle (Fed)

Dr. R. Collé is an internationally-recognized specialist with nearly forty years of experience in nuclear and radiochemistry, radionuclidic metrology, and the development of standards. He has published approximately 120 research papers. He has been at the National Institute of Standards and Technology (NIST) since 1974 and currently serves as a Research Chemist in the Radioactivity Group of the NIST Physical Measurement Laboratory (Radiation Physics Division) and Radioactivity Standard Reference Material Coordinator. Previously, he held research positions at Brookhaven National Laboratory, the State University of New York at Albany, and at the University of Maryland. During a two-year "sabbatical" in Paris (2003-2005), he taught advanced mathematics at the international Victor Hugo School and at American University of Paris. He received a B.Sc. Chemistry from the Georgia Institute of Technology in 1969, a Ph.D. in Physical Chemistry (Nuclear and Radiochemistry) from Rensselaer Polytechnic Institute in 1972, and a M.S. Adm. (Administration of Science and Technology) from George Washington University in 1979. Dr. Collé has been recognized through many awards, including from the American Chemical Society, the Sigma Xi scientific research society, the New York and Pennsylvania Academies of Science, Phi Lambda Upsilon honor society, and two Bronze Medals. In 2011, Elsevier and the journal Applied Radiation and Isotopes awarded him the highly prestigious JARI Medal, only the 10th time in 31 years, for his outstanding contributions in the field of radiation physics. The Washington Academy of Sciences 2015 presented him with its 2015 Award for Distinguished Career in Science in recognition of his lifetime work and major contributions in radionuclide metrology.


Preparation and Standardization of 229Th SRM 4328d

Ronald Colle, Lizbeth Laureano-Perez, Morgan DiGiorgio
The certified massic activity for 229Th in SRM 4328d was obtained by 4παβ liquid scintillation (LS) counting by comparative measurements in 2022 against SRM

Primary standardization of Ra-224 activity by liquid scintillation counting

Denis E. Bergeron, Jeffrey T. Cessna, Ryan P. Fitzgerald, Brian E. Zimmerman, Lizbeth Laureano-Perez, Ronald Colle, Leticia S. Pibida, Elisa Napoli
A standard for 224Ra activity has been developed, based on triple-to-double coincidence ratio (TDCR) liquid scintillation (LS) counting. The standard was

Preparation and calibration of a Protactinium-231 reference material

Richard Essex, Ross W. Williams, Kerri C. Treinen, Ronald Colle, Ryan P. Fitzgerald, Raphael Galea, John Keightley, Jerome LaRosa, Lizbeth Laureano-Perez, Svetlana Nour, Leticia 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

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
Created October 3, 2019, Updated December 8, 2022