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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.
A. D’Angelo,A. Filip
Nuclear Science and Engineering | Volume 114 | Number 4 | August 1993 | Pages 332-341
Technical Paper | doi.org/10.13182/NSE93-A24042
Articles are hosted by Taylor and Francis Online.
The uncertainty of the 235U, 239Pu, and 238U absolute delayed neutron yields vd is one of the principal sources of uncertainty in predicting the fission reactor reactivity scale βeff. The current uncertainties in the dependence of vd on incident neutron energy is investigated for significance in the evaluation of βeff. The uncertainty effects on the GODIVA, JEZEBEL, Zero Power Reactor, SNEAK, and Masurca benchmark facility calculations are analyzed using ENDF/B and JEF basic data. Different assumptions about the energy dependence result in variations of up to 5% in the reactor spectrum averaged values of vd, and these would result in variations of up to ∼2% in the value of βeff for a typical liquid-metal fast breeder reactor.
