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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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A webinar, and a new opportunity to take ANS’s CNP Exam
Applications are now open for the fall 2025 testing period for the American Nuclear Society’s Certified Nuclear Professional (CNP) exam. Applications are being accepted through October 14, and only three testing sessions are offered per year, so it is important to apply soon. The test will be administered from November 12 through December 16. To check eligibility and schedule your exam, click here.
In addition, taking place tomorrow (September 19) from 12:00 noon to 1:00 p.m. (CDT), ANS will host a new webinar, “How to Become a Certified Nuclear Professional.” More information is available below in this article.
T. Fei, M. J. Driscoll, E. Shwageraus
Nuclear Technology | Volume 186 | Number 3 | June 2014 | Pages 378-389
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT13-21
Articles are hosted by Taylor and Francis Online.
The purpose of this study was to demonstrate the neutronic feasibility and competitive fuel cycle economics of sodium fast reactors operating with uranium metal (UZr) fuel on a once-through fuel cycle. Uranium startup fast reactors (USFRs) decouple their deployment from that of expensive reprocessing and recycle facilities. This could facilitate and speed up the deployment of conventional fast reactors, which, in their traditional designs, heavily depend on the availability of reprocessing facilities for transuranic fuel production. The uranium requirement and fuel cycle cost of studied USFR core designs are calculated to be comparable to those of typical light water reactors. The main design constraint is the fast neutron fluence imposed on the cladding material, which is required to be below 5.0×1023 n/cm2 even for advanced oxide dispersion strengthened steels. Therefore, moderators need to be inserted in the fuel assemblies to lower the fast neutron flux so that the fuel residence time limited by neutron fluence can be extended to match the reactivity limited fuel residence time. In this study, magnesium oxide is used for reflectors as well as for the moderator.