ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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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 Science and Engineering
May 2025
Nuclear Technology
Fusion Science and Technology
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.
Hiroshi Fukui, Kaichiro Mishima, Seiji Shiroya, Masatoshi Hayashi, Keiji Kanda, Yasuhide Senda
Nuclear Technology | Volume 70 | Number 3 | September 1985 | Pages 301-317
Technical Paper | Fission Reactor | doi.org/10.13182/NT85-A15958
Articles are hosted by Taylor and Francis Online.
Reactivity of void in the channels between the fuel plates is measured, and the impact of core conversion from using highly enriched uranium (HEU) to medium-enriched uranium (MEU) in the light-water-moderated cylindrical core with heavy water reflector is investigated on this quantity at the Kyoto University Critical Assembly. The void was generated in the flow channels by producing nitrogen gas bubbles through a small needle-like nozzle and the reactivity effect was measured. The void fraction was measured in an outof-pile experiment. The results indicate that the void effect on reactivity is slightly larger (more negative) in the MEU core than in the HEU core. It is also shown that the interference effect of reactivity by bubbling in two adjacent channels simultaneously is within the experimental error.