ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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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
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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July 2025
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Latest News
NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
Melvin M. Levine
Nuclear Science and Engineering | Volume 7 | Number 6 | June 1960 | Pages 545-551
Technical Paper | doi.org/10.13182/NSE60-A25764
Articles are hosted by Taylor and Francis Online.
Breeding ratios for clean near-thermal systems containing only U233 and moderator have been presented by Chernick and Moore (1). The present work treats Pu239 systems also and extends the results in both systems to take account of the effects of the higher isotopes and fission products. The extra absorption by these higher isotopes tends to depress the breeding ratio, but fission in U235 or Pu241 compensate for this, and the net effect, as will be seen, is an increase in breeding ratio for plutonium-fuelled systems.