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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.
J. Dorning
Nuclear Science and Engineering | Volume 41 | Number 1 | July 1970 | Pages 22-28
Technical Paper | doi.org/10.13182/NSE70-A20359
Articles are hosted by Taylor and Francis Online.
Size-dependent extrapolation distances for pulsed-neutron experiments in light-water, spherical, non-multiplying systems have been determined by calculating the buckling in the B-1, 30-group approximation corresponding to a given decay constant. The decay constants for spheres of various radii were taken from an earlier work which reported 30-group Sn calculations of decay constants as a function of system radius. The same 30-group, B-1 method was also used to calculate pulsed-neutron-decay constants as a function of buckling over a wide range of buckling. The static or poisoning experiment inverse-relaxation length, as a function of concentration of a one-over-v poison, was also computed in the same approximation. The resulting data were combined and fitted to yield values of the neutron-diffusion parameters