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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.
D. C. Hunt, Robert E. Rothe
Nuclear Science and Engineering | Volume 46 | Number 1 | October 1971 | Pages 76-87
Technical Paper | doi.org/10.13182/NSE71-A22337
Articles are hosted by Taylor and Francis Online.
The results of criticality measurements on enriched (93.16% 235U) uranium metal spheres symmetrically immersed in enriched (93.18% 235U) uranyl nitrate solution cylinders are reported. The solution cylinders are 26.5, 38.4, and 51.1 cm in diameter with heights ranging from 16 to 70 cm. Solution concentrations, expressed in grams of uranium per liter, are 11.47, 12.55, 13.12, 21.25, 24.20, 24.72, 103.0, and 104.8. Twenty-seven critical systems are identified. The experimental critical parameters of each system are compared with computed values obtained by transport (DTF) and Monte Carlo (KENO) methods. Results from neither, method exhibit a systematic difference from experimental values; the average difference in the critical radius is 2.5% for DTF and 2.0% for KENO. The effects of experimental perturbations are determined experimentally and calculationally.
