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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.
Hem Prabha Raghav
Nuclear Science and Engineering | Volume 78 | Number 1 | May 1981 | Pages 91-96
Technical Note | doi.org/10.13182/NSE78-91
Articles are hosted by Taylor and Francis Online.
The expression for the neutron escape probability from an absorbing body has been expressed in terms of two polynomials. The main feature of these polynomials is that only the coefficients depend on the shape of the geometry while the expressions remain same. At the same time, the resulting expressions for the escape probability ensure the correct behavior in the white and black limits. As examples, numerical results are presented for five geometries: a sphere, a slab, an infinite solid cylinder, a two-dimensional square geometry having infinite height, and a three-dimensional cuboid. The results obtained by using these polynomials match very well with the exact results obtained by using the program POLM, which solves numerically the exact expressions for the escape probability for the respective geometries.