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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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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Surplus plutonium for power reactor fuel: What’s on offer
The Department of Energy has a plan for private companies to “dispose of surplus plutonium”—about 19.7 metric tons in both oxide and metal forms—by “making the materials available for advanced nuclear technologies.” A Surplus Plutonium Utilization Program request for applications (RFA) issued October 21 describes the plutonium on offer, and the “thresholds” prospective applicants must meet.
Akio Yamamoto, Tomohiro Endo
Nuclear Science and Engineering | Volume 193 | Number 9 | September 2019 | Pages 991-997
Technical Paper | doi.org/10.1080/00295639.2019.1579514
Articles are hosted by Taylor and Francis Online.
A new interpretation of the discontinuity factor (DF) for scalar flux, partial current, and angular flux is discussed. Conventionally, the DF is considered as the discontinuous condition of scalar flux, partial current, or angular flux at an interface. In the new interpretation, the DF is considered as the refractive index of materials for partial current or angular flux that conserves odd-parity or odd-moment angular flux at an interface of different materials. It is related to the transmission and reflection of partial current or angular flux at an interface where different materials are adjacent. Using the present interpretation, a fundamental issue of neutron balance (i.e., artificial loss or production of neutrons at an interface due to discontinuous condition), which would appear in the conventional interpretation of DF, can be resolved.