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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. T. Caldwell, E. J. Dowdy, R. A. Alvarez, B. L. Berman, P. Meyer
Nuclear Science and Engineering | Volume 73 | Number 2 | February 1980 | Pages 153-163
Technical Paper | doi.org/10.13182/NSE80-A18695
Articles are hosted by Taylor and Francis Online.
The prompt neutron multiplicities for photofission of the four isotopes 235U, 236U, 238U, and 232Th have been measured with monoenergetic photons over the energy range from 5.5 to 18 MeV using the annihilation in flight of fast positrons. The delayed neutron yield has been measured for all four isotopes at 10.9- and 16.8-MeV photon energies. The ratio of first- to second-chance fission has been measured as a function of energy up to 17-MeV excitation energy for 236U and 238U photofission.