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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.
W. Breitung, K. O. Reil
Nuclear Science and Engineering | Volume 101 | Number 1 | January 1989 | Pages 26-40
Technical Paper | doi.org/10.13182/NSE89-A23592
Articles are hosted by Taylor and Francis Online.
Newly developed in-pile techniques were used to measure the saturation vapor pressure of pure UO2.01, reactor grade UO2.08, and reactor grade (U0.77Pu0.23)O2.09 between 2000 and 3700 kJ/kg. The results for all three fuel types can be described by log Psat (z) = -9.7652 + 8.0934 × 10-3z - 2.0515 × 10-6z2 + 1.9013 × 10-10z3 with z = h-h298 in kilojoules per kilogram and psat in megapascals. The data were converted to the pressure-temperature format and compared to earlier out-of-pile vapor pressure measurements. All out-of-pile measurements that were performed close to a vapor-liquid equilibrium state agree very well with the in-pile results. The following relation is proposed for the p-T saturation line of liquid UO2: log psat (T) = 15.961 - 26974/T - 2.7600 log T, with psat in megapascals and T in degrees kelvin. Because no significant differences were found for all three fuel types investigated, the same saturation vapor pressure is recommended for liquid-metal fast breeder reactor (LMFBR) typical (U,Pu) mixed oxides under LMFBR core disassembly conditions.
