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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Perpetual Atomics, QSA Global produce Am fuel for nuclear space power
U.K.-based Perpetual Atomics and U.S.-based QSA Global claim to have achieved a major step forward in processing americium dioxide to fuel radioisotope power systems used in space missions. Using an industrially scalable process, the companies said they have turned americium into stable, large-scale ceramic pellets that can be directly integrated into sealed sources for radioisotope power systems, including radioisotope heater units (RHUs) and radioisotope thermoelectric generators (RTGs).
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.