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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.
P. A. Ombrellaro
Nuclear Science and Engineering | Volume 44 | Number 2 | May 1971 | Pages 204-220
Technical Paper | doi.org/10.13182/NSE71-A19669
Articles are hosted by Taylor and Francis Online.
Spectral synthesis methods, in which the space-energy flux is synthesized from known flux spectra, are applied to one-dimensional, fast reactor static problems. The methods include few-group synthesis models that employ either the same trial spectra in all regions of the reactor model or different trial spectra in different spatial regions. Numerical results demonstrate that the space-energy flux can be adequately represented by these few-group synthesis models; moreover, the spatially dependent spectra agree very well with similar, “exact” flux spectra calculated by direct multigroup methods. Region-integrated reaction rates calculated with the synthesized flux spectra are in good agreement with those calculated with the flux spectra derived from direct methods.