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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.
Toru Obara, Hiroshi Sekimoto
Nuclear Science and Engineering | Volume 130 | Number 3 | November 1998 | Pages 386-390
Technical Note | doi.org/10.13182/NSE98-A2014
Articles are hosted by Taylor and Francis Online.
The positive neutron temperature coefficient of reactivity of a dilute plutonium-water solution is discussed analytically and numerically. It is explained by the competition of the temperature sensitivity coefficients of microscopic thermal cross sections of fissile materials and absorbers. The use of 176Lu, 180Ta, or 167Er, which have absorption resonances at low energy, in the solution makes it possible for the neutron temperature coefficient of reactivity of a dilute plutonium-water solution to be negative.
