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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.
S. Salah, W. D. Rankin, V. S. Oblock
Nuclear Science and Engineering | Volume 41 | Number 3 | September 1970 | Pages 367-380
Technical Paper | doi.org/10.13182/NSE70-A19095
Articles are hosted by Taylor and Francis Online.
Absolute reaction rates of thermal, resonance, and threshold detectors were calculated and measured within a graphite moderated, graphite reflected critical assembly using NERVA-type fuel elements to provide verification of analytical techniques and basic neutron cross-section data. Detectors used were: Dy, In, Au, W, Mn, Cu, 235U, and 238U foils and S pellets. Comparison of the calculated energy-dependent reaction rates with measured values showed them to be generally within experimental uncertainties. Near the outer edge of the reactor, however, the difference between the calculated and experimental values is greater than the experimental uncertainties. The comparison of these calculations and measurements show that the spatially dependent neutron spectra are adequately predicted with the multigroup, multiregion transport calculations utilized in this analysis.
