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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.
Bruno Pellaud
Nuclear Science and Engineering | Volume 33 | Number 2 | August 1968 | Pages 169-186
Technical Paper | doi.org/10.13182/NSE68-A20655
Articles are hosted by Taylor and Francis Online.
The linear extrapolation distance, extrapolated endpoint, and effective radius of grey and black cylindrical neutron absorbers imbedded in an infinite moderator have been calculated using Kofink's formulation of the PN method, with N odd up to 13. These parameters were determined as functions of the absorption of the moderator and of the linear anisotropic scattering component of the moderator, for two source distributions: 1) uniform isotropic sources; or 2) no sources with a current from infinity. The results are given both in tabular form and in simple formulas that are sufficiently accurate for most purposes. In addition, various kinds of PN boundary conditions are compared and new calculations are given for the blackness of homogeneous grey rods.
