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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.
Karmeshu, N. K. Bansal
Nuclear Science and Engineering | Volume 58 | Number 3 | November 1975 | Pages 321-327
Technical Paper | doi.org/10.13182/NSE75-A26781
Articles are hosted by Taylor and Francis Online.
The exact expressions for the first- and second-order moments of neutron density and the delayed-neutron precursor density are derived for a neutron multiplying system, with time-dependent stochastic perturbations in the reactivity and white noise source. The effect of finite correlation time of the reactivity on the stability of moments is discussed. For asymptotically long times, the moments are found to be stable. The exact expressions of the moments in the limiting case, when the reactivity correlation time becomes zero, are also derived. It is found that the expressions for this limiting case differ from the corresponding expressions of Williams.