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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.
Hans Ludewig
Nuclear Science and Engineering | Volume 44 | Number 1 | April 1971 | Pages 18-26
Technical Paper | doi.org/10.13182/NSE71-A18901
Articles are hosted by Taylor and Francis Online.
An analysis of five metal critical assemblies constructed at the Los Alamos Scientific Laboratory is described in this paper. Nuclear data based on ENDF/B Versions 1 and 2 and the DSN method are used in the analysis. Special attention is focused on the variation of α (the ratio of capture-to-fission cross sections) for 239Pu. A study of the sensitivity of keff to the number of angular quadratures and the scattering model used in the calculation is also investigated. Finally, in addition to determining the reactivity of each core, the spatial variation of a spectral index for two cores is investigated.
