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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.
Hans Ludewig
Nuclear Science and Engineering | Volume 44 | Number 3 | June 1971 | Pages 398-405
Technical Paper | doi.org/10.13182/NSE71-A20170
Articles are hosted by Taylor and Francis Online.
An analysis of the BNL heterogeneity experiment is described in this paper. The nuclear data used are based on ENDF/B Versions I and II and the DSN method is used in the analysis. In addition to determining the intracell fine structure for 235U and 238U fission and Mn capture, the variation of absolute 235U/238U fission ratio as a function of cell size is investigated. From these results it can be concluded that the fission ratio calculations are particularly sensitive to the fission cross section of 235U and 238U, suggesting that measurements of this type could be useful in checking the accuracy of data. The overall agreement between computed and measured quantities was found to be good for all quantities that could be characterized as asymptotic. The non-asymptotic nature of some quantities is investigated using two-dimensional calculations.
