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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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Empowering the next generation: ANS’s newest book focuses on careers in nuclear energy
A new career guide for the nuclear energy industry is now available: The Nuclear Empowered Workforce by Earnestine Johnson. Drawing on more than 30 years of experience across 16 nuclear facilities, Johnson offers a practical, insightful look into some of the many career paths available in commercial nuclear power. To mark the release, Johnson sat down with Nuclear News for a wide-ranging conversation about her career, her motivation for writing the book, and her advice for the next generation of nuclear professionals.
When Johnson began her career at engineering services company Stone & Webster, she entered a field still reeling from the effects of the Three Mile Island incident in 1979, nearly 15 years earlier. Her hiring cohort was the first group of new engineering graduates the company had brought on since TMI, a reflection of the industry-wide pause in nuclear construction. Her first long-term assignment—at the Millstone site in Waterford, Conn., helping resolve design issues stemming from TMI—marked the beginning of a long and varied career that spanned positions across the country.
W. F. G. van Rooijen, J. L. Kloosterman, T. H. J. J. van der Hagen, H. van Dam
Nuclear Science and Engineering | Volume 157 | Number 2 | October 2007 | Pages 185-199
Technical Paper | doi.org/10.13182/NSE07-A2721
Articles are hosted by Taylor and Francis Online.
The Generation IV gas-cooled fast reactor (GCFR) is intended to have a closed fuel cycle: During irradiation enough fissile material is produced to allow refueling of the same reactor, adding only fertile material. This is the well-known "zero breeding gain" objective. In this paper a theoretical framework is derived to track compositional changes of the fuel during irradiation, cooldown, and reprocessing, in order to calculate the reactivity of the new fuel compared to the original fuel material. Using first-order perturbation theory, the effect of variations of the initial fuel composition on the reprocessed material and breeding gain can be calculated. The theory is applied to the fuel cycle of a 600 MW(thermal) GCFR. The result is that the change of material composition during cooldown has a nonnegligible effect on the breeding gain. A truly closed fuel cycle can be obtained if the reprocessing efficiency is high enough (<1% loss). If this high efficiency cannot be obtained, adding a small amount of minor actinides (Np, Am, Cm) to the new fuel results in a zero breeding gain. Perturbation theory provides a powerful tool to estimate the effects of changing fuel cycle parameters.
