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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.
M. Segev, S. Taczanowski
Nuclear Science and Engineering | Volume 91 | Number 2 | October 1985 | Pages 153-161
Technical Paper | doi.org/10.13182/NSE85-A27438
Articles are hosted by Taylor and Francis Online.
The energy distribution of neutrons, from the source energy of 14 MeV down to the (n,2n) threshold, can be approximated by effective one-group cross sections for such high and medium mass number elements as lead, copper, zirconium, and iron. The same is true for 238U, when the fast fission factor ϵ is applied in a special manner to account for the added multiplication below the (n,2n) threshold. Two groups are required to obtain a reasonable description of the amplification in beryllium.
