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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.
Wayne K. Lehto
Nuclear Science and Engineering | Volume 39 | Number 3 | March 1970 | Pages 361-367
Technical Paper | doi.org/10.13182/NSE70-A19996
Articles are hosted by Taylor and Francis Online.
The fission cross-section ratios of 239Pu to 235U and 233U to 235U have been measured from 0.24 to 24 keV using parallel-plate, back-to-back fission detectors and a slowing down lead spectrometer as a neutron source. Relative fission rates obtained from the experiments were converted to true fission cross-section ratios by detector intercalibration in a thermal-neutron flux. In the case of the Pu/U ratio, these results extend the data to below several keV where measurements have not previously been made and the 233U/235U results verify previous measurements made in this energy region.
