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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.
Theodore R. Schmidt, David L. Hetrick
Nuclear Science and Engineering | Volume 42 | Number 1 | October 1970 | Pages 1-9
Technical Paper | doi.org/10.13182/NSE70-A19320
Articles are hosted by Taylor and Francis Online.
The space-independent reactor kinetics equations with two reactivity feedbacks are analyzed for stability and nonlinear oscillations. Expressions are derived using Fourier series methods for determining the frequency and fundamental amplitudes of the oscillations in reactivity and power. These results are compared with exact solutions of the system equations and agree in all cases for equilibrium power levels near the critical power level. The system of equations is examined for the effect of delayed neutrons on oscillatory solutions. When delayed neutrons are included, unstable limit cycles are found as well as stable limit cycles.