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Search Publications by: Ronald Colle (Fed)

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Displaying 1 - 15 of 15

Preparation and Standardization of 229Th SRM 4328d

February 24, 2023
Author(s)
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 4328c. Both SRMs were prepared from the identical 2007 229Th stock solution. SRM 4328c was

Primary standardization of Ra-224 activity by liquid scintillation counting

October 11, 2019
Author(s)
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 confirmed by efficiency tracing and 4παβ(LS)-γ(NaI(Tl)) anticoincidence counting, as well as by 4πγ

Preparation and calibration of a Protactinium-231 reference material

August 22, 2019
Author(s)
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 231Pa - 235U model age measurements associated with nuclear forensics and nuclear safeguards

Ampoules for Radioactivity Standard Reference Materials

August 6, 2019
Author(s)
Ronald Colle
Standard-sized ampoules for radioactive solution standards have been employed by the National Institute of Standards and Technology (NIST) for nearly the past 70 years. This note briefly summarizes the origins and history of the five different batches of

New determination of the 229Th half-life

July 23, 2018
Author(s)
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 had previously been measured. The 229Th massic activity was measured by direct comparison with SRM

Natural Uranium Radioactivity Solution Standard: SRM 4321d

December 27, 2017
Author(s)
Ronald Colle, Lizbeth Laureano-Perez, Svetlana Nour, Jerome J. LaRosa, Brian E. Zimmerman, Leticia S. Pibida, Denis E. Bergeron
A new natural uranium solution standard has been produced and will be disseminated by the National Institute of Standards and Technology (NIST) as Standard Reference Material 4321d. The standard is certified for the massic activities of 234U, 235U, and

Development of an Ultra-Pure, Carrier-Free 209Po Solution Standard

July 23, 2015
Author(s)
Ronald Colle, Ryan P. Fitzgerald, Lizbeth Laureano-Perez
Ultra-pure, carrier-free 209Po solution standards have been prepared and standardized for their massic alpha-particle emission rate. The standards, which will be disseminated by the National Institute of Standards and Technology (NIST) as Standard

On the 209Po Half-Life Error and Its Confirmation: A Critique

June 11, 2015
Author(s)
Ronald Colle, Arthur M. Colle
Collé, et al [(2007) Appl. Radiat Isot. 65, 728; (2014) J. Phys. G: Nucl. Part. Phys. 41, 105103], over the course of nearly a decade and with decay data from a period of 20.7 years, initially uncovered and then substantiated a 25 % error in the 209Po half

The Half-Life of 209Po : Revisited

August 13, 2014
Author(s)
Ronald Colle, Ryan P. Fitzgerald, Lizbeth Laureano-Perez
A substantial 25 % error in the then known and accepted (102  5) year half-life of 209Po was reported on in 2007. This error was detected from decay data from two separate primary standardizations of a 209Po solution standard, which were performed

Standardization of 237Np

December 4, 2013
Author(s)
Lizbeth Laureano-Perez, Ryan P. Fitzgerald, Ronald Colle
The standardization of 237Np was investigated. The certified massic activity for 237Np was obtained by 4 liquid scintillation (LS) counting with correction for the 233Pa daughter using the CIEMAT/NIST efficiency tracing method using a 3H standard

Effect of Neutron Irradiation on Dosimetric Properties of the TLD-600H (Lif6:Mg,Cu,P)

November 1, 2011
Author(s)
Alexander A. Romanyukha, Ronaldo Minniti, M. Moscovitch, Alan Keith Thompson, F. Trompier, Ronald Colle, A Sucheta, S. P. Voss, L. A. Benevides
Ideally, dosimeters should measure the dose without their dosimetric properties being affected by the radiation type being measured. Industry-wide occupational radiation workers that can be potentially exposed to neutron radiation fields are routinely

Investigation into the Standardization of Tc-99

July 30, 2010
Author(s)
Lizbeth Laureano-Perez, Ronald Colle, Ryan P. Fitzgerald, Brian E. Zimmerman, Lonnie T. Cumberland
The standardization of 99Tc by several primary methods was investigated. This was performed to support a new 99Tc transfer standard that has been developed and will be disseminated by the National Institute of Standards and Technology (NIST) as Standard

Radionuclide Standardization by Primary Methods: An Overview

February 17, 2009
Author(s)
Ronald Colle
Primary methods of radionuclidic standardization serve as the underlying basis of the physical measurement standards of activity that are needed in virtually every sub-discipline of radioanalytical and nuclear chemistry. Primary methods refer to the direct

Classical Radionuclidic Calorimetry

August 2, 2007
Author(s)
Ronald Colle
This brief survey summarizes the principles and practice of classical isothermal microcalorimetry for the primary standardization of the activity of radionuclides. Its advantages and some potential problems are highlighted through the discussion of several