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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.
Ken Nakajima, Masanori Akai, Takenori Suzaki
Nuclear Science and Engineering | Volume 119 | Number 3 | March 1995 | Pages 175-181
Technical Paper | doi.org/10.13182/NSE95-A24083
Articles are hosted by Taylor and Francis Online.
The modified conversion ratio (MCR) (the ratio of the 238U capture rate to the total fission rate) in a light-water-moderated uranium-plutonium mixed-oxide- (MOX-) fuel lattice was measured for four types of lattices with different plutonium enrichment. In the current method, the relative reaction rates of 238U capture and total fission were obtained from nondestructive gamma-ray spectrometry of 239Np and fission products, respectively, which accumulated in the fuel rod irradiated at the Tank-Type Critical Assembly. The measured results of the fission rates derived from two different fission products agreed well with each other, and the measured MCRs showed good agreement with the results of the Monte Carlo calculation with the whole-core model. Therefore, the current nondestructive method is applicable to the MCR measurement of MOX fuel.
