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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.
Hideki Takano, Kunio Kaneko
Nuclear Science and Engineering | Volume 77 | Number 2 | February 1981 | Pages 250-256
Technical Note | doi.org/10.13182/NSE81-A21358
Articles are hosted by Taylor and Francis Online.
Self-shielding factors for inelastic scattering cross sections of iron are calculated from the evaluated nuclear data flies ENDF/B-IV and JENDL-2. The effect of self-shielding by inelastic scattering on the neutron spectra is studied for fast reactor assemblies ZPR-3-54 and MZB, the fast critical assembly of the Japanese fast reactor program. The effect is very pronounced, especially in the steel reflector, where the spectrum is shifted to higher energy. The radial distribution of fission reaction rates calculated by considering that the self-shielding effect becomes smaller for 235U and 239Pu, but larger for 238U in the blanket and reflector regions.
