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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.
Erkang Li
Nuclear Science and Engineering | Volume 85 | Number 1 | September 1983 | Pages 61-70
Technical Note | doi.org/10.13182/NSE83-A17153
Articles are hosted by Taylor and Francis Online.
A method for calculating the first-flight collision probabilities in an annular region containing identical cylindrical fuel rods is described. Based on the assumptions of flat isotropic neutron sources and isotropic incidence fluxes on boundary surfaces, 5 of the 15 probabilities in the annular region are calculated. By neutron conservation and the reciprocity theorem, the other 10 probabilities are obtained in terms of the first 5. The results are satisfactory in comparison to other existing theories. The method can be used in the treatment of a cluster-type fuel assembly.
