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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.
J. Ligou
Nuclear Science and Engineering | Volume 63 | Number 1 | May 1977 | Pages 31-40
Technical Paper | doi.org/10.13182/NSE77-A27001
Articles are hosted by Taylor and Francis Online.
On the basis of a point kinetic model (adiabatic approximation), the explosion of fissionable pellets is analyzed. The needed kinetic parameters are derived from steady-state multigroup transport calculations. The effect of the reflectors is included not only in the critical mass determination but also in the kinetic behavior of the pellets through the effective lifetime. Although the hydrodynamic expansion is not considered, fuel burnup is taken into account to ascertain the time needed for maximum efficiency. This time is then compared to the disassembly time. A simple formalism is included that directly gives the microexplosion efficiency. Most of the numerical results are related to Li-D-reflected plutonium pellets. The ignition of the fission chain reactions is provided by fusion neutrons produced in the reflector, but the bootstrap mechanism between fission and fusion is not included.