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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.
L. Green, J. J. Ullo
Nuclear Science and Engineering | Volume 67 | Number 2 | August 1978 | Pages 172-183
Technical Paper | doi.org/10.13182/NSE78-A15434
Articles are hosted by Taylor and Francis Online.
The spatial distribution of the total neutron density from a 252Cf source in pure water was measured to high statistical precision at distances ranging from 11 to 80 cm from the source. Assuming the adequacy of the ENDF/B-IV hydrogen cross sections and reasonable constraints on the fission spectrum mean energy, good agreement between experiment and a one-dimensional transport calculation was obtained for both ENDF/B-III and -IV oxygen cross sections, with Version III being slightly better. However, small residual differences remained that could not be removed by adjustment of the spectrum mean energy alone.