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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.
P. H. Kier, M. Salvatores
Nuclear Science and Engineering | Volume 53 | Number 4 | April 1974 | Pages 479-482
Technical Note | doi.org/10.13182/NSE74-A23379
Articles are hosted by Taylor and Francis Online.
Samples used in Doppler-effect measurements in fast critical assemblies distort the flux in their vicinity. For fissile samples whose Doppler effect depends strongly on spectrum, this distortion may strongly affect the measured results. An integral transport method for computing distorted real and adjoint fluxes is developed and the fissile-sample Doppler measurements in a fast critical assembly, ZPR-6 Assembly 7, are analyzed. It was found that the local flux distortions strongly affect the results and for a PuO2 sample even change the algebraic sign of the Doppler effect.
