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NRC proposes changes to its rules on nuclear materials
In response to Executive Order 14300, “Ordering the Reform of the Nuclear Regulatory Commission,” the NRC is proposing sweeping changes to its rules governing the use of nuclear materials that are widely used in industry, medicine, and research. The changes would amend NRC regulations for the licensing of nuclear byproduct material, some source material, and some special nuclear material.
As published in the May 18 Federal Register, the NRC is seeking public comment on this proposed rule and draft interim guidance until July 2.
M. Salvatores
Nuclear Science and Engineering | Volume 50 | Number 4 | April 1973 | Pages 345-353
Technical Paper | doi.org/10.13182/NSE73-A26569
Articles are hosted by Taylor and Francis Online.
The benchmark experiments, performed in a plutonium-fueled critical assembly (ZPR-6 Assembly 7) in support of the fast reactor demonstration plant program, were used, in conjunction with a statistical method of correlation, as a source of suggestions for possible modifications to multigroup neutron cross-section sets based on ENDF/B files. Version 1 of these files was a starting point in the correlation procedure. The general trends of the results (lower 238U capture cross section and 235U fission cross section, higher 239Pu capture to fission ratio, with respect to ENDF/B Version 1 data) are discussed, and the suggested multigroup cross-section adjustments are compared with recent evaluations. Calculations of keff, and of the ratios of 238U and 235U fission rate and of 238U capture rate to 239Pu. fission rate, using the proposed adjusted set, give results in good agreement with the experiments.
