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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. Spiegel
Nuclear Science and Engineering | Volume 53 | Number 3 | March 1974 | Pages 326-327
Technical Note | doi.org/10.13182/NSE74-A23358
Articles are hosted by Taylor and Francis Online.
The effective half-life of 252Cf has been determined as 2.638 ± 0.007 yr. The method utilized the ratio of the manganese activity induced in a manganous-sulfate bath by a 252Cf spontaneous-fission neutron source and the National Bureau of Standards photo-neutron source to measure the change in emission rate of the 252Cf source over a period of 1.77 half-lives. The data were corrected for the activity of radium (1622-yr half-life) in the photoneutron source (-0.2%) and for the competing neutron production from 250Cf.
