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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
Standards Program
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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Nuclear Technology
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Latest News
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
G. Giacchetti, C. Sari, C. T. Walker
Nuclear Technology | Volume 28 | Number 2 | February 1976 | Pages 216-225
Technical Paper | Fuel | doi.org/10.13182/NT76-A31562
Articles are hosted by Taylor and Francis Online.
The distribution of the actinides and the composition of metallic fission-product inclusions and oxide inclusions in a mixed-nitride fuel irradiated to 1.29% FIMA in a fast flux has been investigated using an electronprobe microanalyser. Plutonium enrichment was found at open and healed cracks, and a significant decrease in plutonium concentration was measured in the region of the central void. Metallic inclusions were detected in a band at a radial position r/r0 -0.7 to 0.8. The inclusions were of two types: intermetallic compounds of the form UMe3, where Me =ruthenium, rhodium, and palladium, and molybdenum-technetium alloys. Plutonium was absent in all inclusions examined. Oxide inclusions were observed in the outer part of the fuel at r/r0 > 0.5. These were also of two types. The first contained ∼5 wt% plutonium and was situated in the interior of the grains. The second had a plutonium concentration of ∼18 wt% and was found at grain boundaries. The plutonium concentration of both types of inclusions was lower than the nominal concentration of the fuel matrix. During irradiation oxide inclusions were formed in the outer part of the fuel by the oxidation of sesquinitride precipitates. The limit of plutonium solubility in uranium sesquinitride is proposed to be ∼5 wt%.
