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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. K. Fletcher
Nuclear Science and Engineering | Volume 84 | Number 1 | May 1983 | Pages 33-46
Technical Paper | doi.org/10.13182/NSE83-A17455
Articles are hosted by Taylor and Francis Online.
A solution of the multigroup neutron transport equation in one, two, or three space dimensions is presented. The flux φg(r, Ω) at point r in direction for energy group g takes the form of an expansion in unnormalized spherical harmonics. Thus, where θ and φ are the axial and azimuthal angles of Ω, the associated Legendre polynomials, and N an arbitrary odd number. Using the various recurrence formulas for , a linked set of first-order differential equations in the moments results. Terms with odd 1 are eliminated yielding a second-order system to be solved by two methods. First, a finite difference formulation using an iterative procedure is given, and second, in XYZ and XY geometry, a finite element solution is presented. Results for a test problem using both methods are exhibited and compared.