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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.
James W. Meadows
Nuclear Science and Engineering | Volume 79 | Number 2 | October 1981 | Pages 233-237
Technical Note | doi.org/10.13182/NSE81-A27412
Articles are hosted by Taylor and Francis Online.
The 240Pu-to-235U fission cross-section ratio has been measured at 55 discrete energies between thresh-old and ∼10 MeV using the 7Li(p,n)7Be and D(d,n)3He reactions as neutron sources. The sample masses were measured by (a) calculated specific activities and low geometry alpha counting, (b) by mass spectrographic isotopic dilution analyses, and (c) by comparing the relative thermal fission rates of one of the 235U samples with 240Pu samples containing ∼9% 239Pu.
