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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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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Latest News
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.
C. R. Adkins, T. E. Murley, M. W. Dyos
Nuclear Science and Engineering | Volume 36 | Number 3 | June 1969 | Pages 336-350
Technical Paper | doi.org/10.13182/NSE69-A18732
Articles are hosted by Taylor and Francis Online.
The well-known approximations used for finding multigroup cross sections and the Doppler coefficient are examined to determine their validity. The method involves comparing the approximate methods of one fast-reactor cross-section code (MC2) with a more rigorous treatment which removes most of the approximations. The unresolved resonance region makes a considerable contribution to the Doppler coefficient in fast reactors, and this region is treated more precisely by generating pseudo resonances using random sampling techniques within the Breit-Wigner single level formalism. A procedure is developed which ensures that the generated pseudo resonances are consistent with measured pointwise data. The resonance data is used in an ultra-fine energy group integral transporttheory code which treats the space-dependent slowing down problem in a very precise manner. A numerical comparison between the approximate methods used in MC2 and those used in the more rigorous calculations is made for a mixed carbide, sodium-cooled fast breeder reactor. Aside from some very significant detailed differences, it is shown that the approximations used in MC2 are not too severe, and that the code is adequate for determining the multigroup cross sections and the Doppler coefficient. The more rigorous method is a very time consuming and detailed procedure not well suited for design calculations. It is intended to serve as a standard, to which more approximate methods can be compared.