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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. d'Oultremont, J. C. Young, J. M. Neill, C. A. Preskitt
Nuclear Science and Engineering | Volume 45 | Number 2 | August 1971 | Pages 141-155
Technical Paper | doi.org/10.13182/NSE71-A20881
Articles are hosted by Taylor and Francis Online.
A subcritical time-of-flight spectrum facility (STSF) has been used to study the neutron spectra and kinetics of two fast assemblies designated STSF-2 and STSF-2A. Neutron spectra have been measured by the time-of-flight method between 5 MeV and 500 eV in the core and the reflector of the STSF-2 which is essentially the same as the ZPR-3 Assembly 17. The STSF-2 core was loaded with plate type elements and the neutron spectrum was determined at the surface of a graphite plate, an enriched uranium plate, and a depleted uranium plate. Detailed transport calculations have been performed with ENDF/B version 1 cross sections and compared to the experimental data which had been reduced by an original method. Finally, kinetic measurements have been performed on assembly STSF-2A which confirm the validity of the time-dependent calculations involved in the time-of-flight data analysis.