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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.
Masatoshi Kawashima, Tadashi Yoshida, Tsugio Yokoyama, Toshihisa Yamamoto
Nuclear Science and Engineering | Volume 103 | Number 2 | October 1989 | Pages 210-218
Technical Note | doi.org/10.13182/NSE89-A28508
Articles are hosted by Taylor and Francis Online.
Gamma-dose analysis was performed on an absolute-value basis at the zero-power plutonium reactor (ZPPR)-13B/4 critical assembly, which was one of the benchmark radially heterogeneous 650-MW(electric) liquid-metal reactor cores, to validate the current data and methods applicable to power reactor design calculations. Discussions of particular aspects inherent to the critical measurements, such as heterogeneity in the ZPPR plate cells and delayed fission product gamma effect, are included. The results showed that the gamma-energy deposition distribution was reproduced within an accuracy of ∼10% in cores that had complicated fuel and internal blanket layouts.