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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.
C. L. Williams, A. C. Peterson, Jr.
Nuclear Science and Engineering | Volume 68 | Number 2 | November 1978 | Pages 155-169
Technical Paper | doi.org/10.13182/NSE78-A27286
Articles are hosted by Taylor and Francis Online.
Flow patterns that occur in a rod bundle with forced upward flow of boiling water have been photographed. The experimental rod bundle consisted of four vertical 0.25-in.-diam × 24.0-in. long rods arranged in a single row with spring collar supports. The tested conditions were: pressure—400 to 2000 psia, mass velocity—250 000 to 3 000 000 lb/h-ft2, and heat flux (uniform)—up to 1 600 000 Btu/h·ft2. The observed two-phase flow patterns were bubble flow, froth flow, slug flow, and annular flow. These flow patterns were mapped at constant pressure on plots of mass velocity versus flowing quality.