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Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
John M. Jamieson, Geoffrey G. Eichholz
Nuclear Technology | Volume 39 | Number 1 | June 1978 | Pages 95-100
Nuclear Safety Analysis | Energy Modeling and Forecasting / Analysis | doi.org/10.13182/NT78-A17011
Articles are hosted by Taylor and Francis Online.
A method for analyzing nuclear material for different fissile nuclides by cyclic activation has been developed and tested experimentally with samples of 235U and 239Pu, singly and in combination. The method of analysis is based on the differences in the abundances and half-lives of delayed neutron groups between the various fissile nuclides. The steady-state delayed neutron response to periodic activation is independent of activation cycle period at short periods, decreases exponentially with period at long periods, and has a break point, or knee, where the response changes from constant to exponential, or from one exponential to another, with greater slope for each characteristic emitter present. The activation cycle periods at which these break points occur, the slopes of the exponential fall-off or response with cycle period between break points, and the absolute magnitude of the response at any cycle period are all functions of the effective half-lives and abundances of the delayed neutron precursors activated, so, consequently, the characteristic delayed neutron response as a function of activation cycle period is different for the various fissile species. In the experiment, cyclic activation was accomplished by moving the samples containing fissile material cyclically through a thermal-neutron beam from the Georgia Tech Research Reactor, out of the beam and through a delayed neutron detector, and back through the beam, etc. The delayed neutron response was recorded at activation cycle periods ranging from 0.1 to 100 s for samples containing varying amounts of 235U and 239Pu. Deviations in the responses of the samples containing both 235U and 239Pu from the response of standards containing only 235U or 239Pu were determined to infer the 235U- to-239Pu ratio. After the ratio of the two fissile nuclides present was obtained, the delayed neutron response at short cycle periods was used to estimate the mass of each fissile nuclide present in the sample. For samples containing about a gram of fissile material, accuracies on the order of 2% for 235U and 4% for 239Pu could be obtained for 1.5-h experiment run times when the fissile nuclides were present in about equal portions. Accuracies were dependent on the 235U-to-239Pu ratio and on the total mass of fissile materials present.
