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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.
W. Robert Sloan, Gene L. Woodruff
Nuclear Science and Engineering | Volume 55 | Number 1 | September 1974 | Pages 28-40
Technical Paper | doi.org/10.13182/NSE74-A23963
Articles are hosted by Taylor and Francis Online.
Measurements of the spectra of delayed neutrons from the thermal fission of 235U are reported over the energy range 30 to 1500 keV. The resolution is sufficient to identify locations of peaks in the spectra. Spectra for three different count-irradiation cycles are reported with the shortest representing a near equilibrium spectrum for delayed neutrons from 235U. Comparisons with existing data show relatively good agreement to the spectral peaks. A correction for the shield of the detector is introduced and applied to the current and previous work with reasonable results. In general, the new spectra are softer than previously reported and show more detailed structure.