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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.
Wayne J. Mikols, J. Kenneth Shultis
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 738-743
Technical Note | doi.org/10.13182/NSE77-A15215
Articles are hosted by Taylor and Francis Online.
It is shown that for transport problems involving fine-energy-group structure or light element scattering, the elastic scattering transfer cross sections can be approximated by trapezoid-shaped distributions. In particular, for group structures of equal lethargy widths, the trapezoidal distribution reduces to a triangular shape. These approximate transfer cross sections are readily incorporated into a discrete ordinates code and often produce results superior to those obtained with conventional Legendre expansion techniques.