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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.
W. Seifritz, P. Wydler
Nuclear Science and Engineering | Volume 72 | Number 2 | November 1979 | Pages 272-276
Technical Note | doi.org/10.13182/NSE79-A19473
Articles are hosted by Taylor and Francis Online.
The physics parameters of a bare sphere of metallic 237Np have been investigated. The calculations indicate that a chain reaction can be sustained with fast neutrons. The predicted critical radius is 8.86 cm, and the corresponding critical mass is 59.7 kg. Kinetic parameters such as the prompt neutron lifetime, l, the prompt neutron decay constant at delayed criticality, αc, and the effective delayed neutron fraction, βeff, were also calculated. With respect to the last quantity, the phenomenon of the so-called “vanishing dollar” in systems consisting of even-neutron nuclei is discussed. Some remarks concerning the possible utilization of 237Np, which is produced in nuclear power reactors as a by-product, are appended.
