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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.
David J. Loaiza, Glenn Brunson, Rene Sanchez, Ken Butterfield
Nuclear Science and Engineering | Volume 128 | Number 3 | March 1998 | Pages 270-277
Technical Paper | doi.org/10.13182/NSE98-A1955
Articles are hosted by Taylor and Francis Online.
The delayed neutron activity resulting from the fast induced fission of 235U and 237Np has been studied. The six-group decay constants, relative abundances, and absolute yield of delayed neutrons from fast fission of 235U and 237Np were measured using the Godiva IV fast assembly at the Los Alamos Critical Experiments Facility. The absolute yield measured for 235U was 0.0163 ± 0.0008 neutron/fission. This value compares very well with the well-established Keepin absolute yield of 0.0165 ± 0.0005. The absolute yield value measured for 237Np was 0.0126 ± 0.0007. The measured delayed neutron parameters for 235U are corroborated with period (e-folding time) versus reactivity calculations.
