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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.
J. M. Neill, J. C. Young, C. A. Preskitt, G. D. Trimble, R. C. Lloyd, C. L. Brown
Nuclear Science and Engineering | Volume 46 | Number 2 | November 1971 | Pages 244-254
Technical Paper | doi.org/10.13182/NSE71-A22358
Articles are hosted by Taylor and Francis Online.
Neutron spectrum measurements covering the range thermal to 3 keV have been made by time-of-flight in three solutions of plutonium nitrate. The concentrations and 240 Pu composition of these solutions were 197.9 g/liter at 23 wt%, 193.4 g/liter at 5 wt%, and 355.0 g/liter at 5 wt%, respectively. Flux traverses and time-dependent measurements were also made in each solution. The measured spectra have been compared to theoretical calculations using the Haywood-II scattering kernel for H bound in H2O and the ENDF/B Version I cross sections for 239Pu. A good comparison is obtained for the two lowest concentrations. The disagreements for the highest concentration are ascribed to room return effects.
