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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.
T. A. Gabriel, B. L. Bishop
Nuclear Science and Engineering | Volume 68 | Number 1 | October 1978 | Pages 94-99
Technical Note | doi.org/10.13182/NSE78-A27274
Articles are hosted by Taylor and Francis Online.
The sensitivity of primary knock-on atom (PKA) spectra and displacement per atom (dpa) cross sections to different secondary neutron energy and angular distributions and “in-group” weighting schemes is investigated. It is shown that the sensitivity of the PKA spectra and dpa cross sections for the (n, n′ unresolved) and (n, 2n) reactions in iron to different angular distributions and the same secondary neutron spectrum is reasonably large (∼15%). For grossly different secondary neutron spectra and the same angular distribution, the change in the dpa cross section is smaller than one would initially expect. It is also shown that for aluminum, the sensitivity of dpa cross sections to different in-group weighting schemes is, for the most part, small.
