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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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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.
J. H. Shaffer, W. R. Grimes, G. M. Watson, D. R. Cuneo, J. E. Strain, M. J. Kelly
Nuclear Science and Engineering | Volume 18 | Number 2 | February 1964 | Pages 177-181
Technical Paper | doi.org/10.13182/NSE64-A18316
Articles are hosted by Taylor and Francis Online.
In the conceptual two-region molten-salt breeder reactor, fissionable U233 will be recovered from the blanket as the decay product of Pa233. Since equilibrium concentrations of Pa233 would result in appreciable parasitic neutron absorptions, the advantages of thermal breeding could be realized to a greater extent by removing both Pa233 and U233 from the blanket mixture. Methods for recovering these materials from molten-fluoride mixtures by precipitation as oxides are presented. Small-scale experiments clearly indicated that it is possible to remove protactinium from molten-fluoride solutions by a process that appears to be surface precipitation of protactinium on beryllium oxide or thorium oxide particles. Protactinium was removed from molten mixtures of LiF-BeF2-ThF4 (67-18-15 mole %) by the addition of 1 to 2% by weight of solid beryllium oxide or thorium oxide. The removal efficiency was high when the initial concentration of protactinium was either in the range 1 to 2 ppb or 50 to 75 ppm. Uranium was successfully removed from solution in molten fluorides by use of a similar procedure. Approximately 2000 ppm uranium was precipitated from molten LiF-BeF2-ThF4 (67-18-15 mole %) by the addition of 3% by weight of beryllium oxide. Comparable results were also obtained using thorium oxide as the precipitant.
