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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.
Sheng Fan, Xiaochun Shi, Fang Yan, Hongzhou Zhang, Zhixiang Zhao
Nuclear Science and Engineering | Volume 147 | Number 1 | May 2004 | Pages 63-72
Technical Paper | doi.org/10.13182/NSE04-A2419
Articles are hosted by Taylor and Francis Online.
To simplify the calculation, some assumptions are considered in the current work. The preequilibrium emission in the first step in the equilibrium process, which is characterized by exciton n = 3 and "never come back," is considered in the preequilibrium emission process; the alpha emission is only completed with the neutron and proton emission, and the second particle emission is neglected. Under those assumptions, a semiempirical systematics of the cross section for the (n,) reaction is obtained on the basis of the evaporation and exciton models for the energies ranging up to 20 MeV. Within the nuclide mass region of 23 A 209, a strong dependence on (N - Z + 1)/A and the incident neutron has been observed. The predictions of the semiempirical systematics with the global parameter of the excitation functions for the (n,) reaction are in good agreement with the experimental data.