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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.
M. Nakano, H. Tsunoda, J. Hirota
Nuclear Science and Engineering | Volume 87 | Number 3 | July 1984 | Pages 283-294
Technical Paper | doi.org/10.13182/NSE84-A17783
Articles are hosted by Taylor and Francis Online.
An experimental study has been made on FCA Assembly VIII-2 to test the validity of the calculational method for the reactivity effect due to axial displacement of fuel and cladding. The emphasis was placed on the systematic measurement of reactivity change and flux distribution in simple configurations rather than the simulation of a possible accident sequence. The analysis was made using the Japan Atomic Energy Research Institute Fast Set Version II. The transport calculation with an S4P0 approximation predicts both the reactivity change and the fission rates of 235U and 238U fairly well, although there still remains the trend of underestimation of reactivity effect, which increases with expansion of the fuel slumping to the core edge.
