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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.
J. B. Yasinsky
Nuclear Science and Engineering | Volume 39 | Number 2 | February 1970 | Pages 241-256
Technical Paper | doi.org/10.13182/NSE70-A21204
Articles are hosted by Taylor and Francis Online.
The results of a numerical study as to the adequacy of the point kinetics method for analyzing rod-ejection accidents are presented. Two-group slab representations of three different seed-blanket reactors are considered. Five different point kinetics formulations are considered for each fictitious rod-ejection accident considered; each formulation being characterized by the shape functions used to calculate the instantaneous reactivity. From these numerical studies we conclude that the accuracy of a point model, for rapid, nonseparable transients of the type considered, is extremely dependent upon the specifics of the particular model (i.e., on the shape function used), and in general one cannot assume a priori that a specific point model is conservative or nonconservative.