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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.
Gregory D. Spriggs
Nuclear Science and Engineering | Volume 115 | Number 1 | September 1993 | Pages 76-80
Technical Notes | doi.org/10.13182/NSE93-A35525
Articles are hosted by Taylor and Francis Online.
The effective delayed neutron fraction of a solution reactor fueled with highly enriched ura-nyl nitrate was measured using two Rossi-a techniques: the “slope” method and the Nelson number method. The average value of the effective delayed neutron fraction was measured to be 0.0147 ± 13%, which is significantly higher than the calculated value of0.009. The discrepancy between the measured and the calculated value is not understood at this time, but it is suspected that the majority of the bias is associated with the measurement of the intrinsic neutron source strength.
