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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.
V. O. Uotinen, J. H. Lauby, W. P. Stinson, S. R. Dwivedi
Nuclear Science and Engineering | Volume 44 | Number 1 | April 1971 | Pages 66-71
Technical Paper | doi.org/10.13182/NSE71-A18906
Articles are hosted by Taylor and Francis Online.
The ratio βeff/l has been deduced from reactor noise measurements in several uniform light-water lattices in the Plutonium Recycle Critical Facility. These lattices included one in which the fissile material was slightly enriched uranium, one in which the fissile material was plutonium, and five lattices in which the fissile material contained both uranium and plutonium. These measurements supply a set of experimental data over a range of plutonium enrichments that are applicable to plutonium recycle situations in thermal reactors. The measured values of βeff/l range from 33 ± 3 sec−1 for a lattice of Al-Pu rods to 153 ± 8 sec−1 for a lattice of UO2 rods. Calculated values of βeff/l, obtained with a straight-forward reactor design calculational method, are in good agreement with measured values.
