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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.
Eiping Quang, Glenn F. Knoll
Nuclear Science and Engineering | Volume 110 | Number 3 | March 1992 | Pages 282-288
Technical Paper | doi.org/10.13182/NSE90-99
Articles are hosted by Taylor and Francis Online.
The cross section of the reaction 238U(n,γ)239U is measured at neutron energies of 23 and 964 keV. Photoneutron sources Sb-Be and Na-Be are calibrated using a manganese bath traceable to the National Bureau of Standards neutron source NBS-I and are provided nearly monoenergetic neutron irradiation. Neptunium-239 from the decay of 239U is chemically separated from the uranium target and is counted to determine the reaction rate. An 242Am foil is used as an absolute gamma-ray calibration standard in the determination of the induced activity. The resulting cross-section values are 491 ± 11 and 138 ± 5 mb at 23 and 967 keV, respectively.