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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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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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Proposed rule for more flexible licensing under Part 53 is open for comment
The Nuclear Regulatory Commission has published a proposed rule that has been five years in the making: Risk-Informed, Technology-Inclusive Regulatory Framework for Advanced Reactors. The rule, which by law must take its final form before the end of 2027, would let the NRC and license applicants use technology-inclusive approaches and risk-informed, performance-based techniques to effectively license any nuclear technology. This is a departure from two licensing options with light water reactor–specific regulatory requirements that applicants can already choose.
Dieter Pachur
Nuclear Technology | Volume 59 | Number 3 | December 1982 | Pages 463-475
Technical PaperTechnical Paper | The Backfill as an Engineered Barrier for Radioactive Waste Management / Material | doi.org/10.13182/NT82-A33004
Articles are hosted by Taylor and Francis Online.
Heat treatment after irradiation of reactor pressure vessel steels showed annealing of irradiation embrittlement. Depending on the irradiation temperature, the embrittlement started to anneal at ∼220°C and was completely annealed at 500°C with 4 h of annealing time. The annealing behavior was normally measured in terms of the Vickers hardness increase produced by irradiation relative to the initial hardness as a function of the annealing temperature. Annealing results of other mechanical properties correspond to hardness results. During annealing, various recovery mechanisms occur in different temperature ranges. These are characterized by activation energies from 1.5 to 2.1 eV. The individual mechanisms were determined by the different time dependencies at various temperatures. The relative contributions of the mechanisms showed a neutron fluence dependence, with the lower activation energy mechanisms being predominant at low fluence and vice versa. In the temperature range where partial annealing of a mechanism took place during irradiation, an increase in activation energy was observed. Trend curves for the increase in transition temperature with irradiation, for the relative increase of Vickers hardness and yield strength, and for the relative decrease of Charpy-V upper shelf energy are interpreted by the behavior of different mechanisms.