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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.
R. S. Tanczyn, Q. Sharfuddin, W. A. Schier, D. J. Pullen, M. H. Haghighi, L. Fisteag, and G. P. Couchell
Nuclear Science and Engineering | Volume 94 | Number 4 | December 1986 | Pages 353-364
Technical Paper | doi.org/10.13182/NSE86-A18346
Articles are hosted by Taylor and Francis Online.
Composite delayed neutron energy spectra from the thermal neutron fission of 235U have been measured for eight delay-time intervals between 0.17 and 85.5 s. Our experimental technique combines a helium-jet and tape transfer system with a beta-neutron time-of-flight spectrometer. The neutron energy range of 0.01 to 2.0 MeV is spanned with 6Li-glass, plastic, and liquid scintillators. Spectra are compared to ENDF/B-V as well as to individual precursors' data and average energies are tabulated for the present and previous compilations. An equilibrium spectrum is also calculated and compared to ENDF/B-V and individual precursor measurements.
