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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. F. Hansen, J. D. Anderson, R. J. Doyas, R. J. Howerton, T. Komoto, C. M. Logan, C. Wong, J. L. Kammerdiener
Nuclear Science and Engineering | Volume 55 | Number 3 | November 1974 | Pages 345-348
Technical Note | doi.org/10.13182/NSE74-A23461
Articles are hosted by Taylor and Francis Online.
The neutron spectra emitted from 2 and 4 mean-free-paths of concrete irradiated by 14-MeV neutrons have been measured between 14 and 2 MeV using the sphere transmission and time-of-flight techniques. The spectra have been calculated with the Monte Carlo neutron transport code TART using the ENDL Livermore neutron library and the ENDF/B-III neutron library. From the comparison between measurements and calculations, it was inferred that the nonelastic cross section for oxygen in the ENDL library was too large. A revision of the cross sections for 14- and 14.6-MeV neutrons was carried out and resulted in very good agreement between measurements and calculations.
