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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.
Hiroshi Takada, Shin-ichro Meigo, Toshinobu Sasa, Kazufumi Tsujimoto, Hideshi Yasuda
Nuclear Science and Engineering | Volume 135 | Number 1 | May 2000 | Pages 23-32
Technical Paper | doi.org/10.13182/NSE00-A2121
Articles are hosted by Taylor and Francis Online.
Reaction rate distributions of various activation detectors such as the natNi(n,x)58Co, 197Au(n,2n)196Au, and 197Au(n,4n)194Au reactions were measured to study the production and the transport of spallation neutrons in a lead assembly bombarded with protons of 500 MeV. The measured data were analyzed with the nucleon-meson transport code NMTC/JAERI combined with the MCNP4A code using the nuclide production cross sections based on the JENDL Dosimetry File and those calculated with the ALICE-F code. It was found that the NMTC/JAERI-MCNP4A calculations agreed well with the experiments for the low-energy-threshold reaction of natNi(n,x)58Co. With the increase of threshold energy, however, the calculation underestimated the experiments, especially above 20 MeV. The reason for the disagreement can be attributed to the underestimation of the neutron yield in the tens of mega-electron-volt regions by the NMTC/JAERI code.
