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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.
George W. Eccleston, Gene L. Woodruff
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 636-651
Technical Paper | doi.org/10.13182/NSE77-A15207
Articles are hosted by Taylor and Francis Online.
Measurements of the near-equilibrium energy spectra of the delayed neutrons associated with fast-neutron-induced fissions of 232Th, 233U, 235U, 238U, and 239Pu are reported over the energy range from 35 to 1500 keV. The fission source spectrum, produced from the 9Be(p, n)9B reaction using 10-MeV protons, approximated a prompt fission spectrum. Over 20% of the delayed neutrons in the measured spectra for each sample appeared below 100 keV. Two large peaks at 41 and 74 keV were observed in the spectra from each nuclide. The measured spectra compare favorably with the data reported by others at energies above 200 keV. However, at energies below this value, our results show a significant increase in the number of delayed neutrons when compared with previously published results.
