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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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Latest News
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.
D. R. Haffner, R. W. Hardie
Nuclear Technology | Volume 42 | Number 2 | February 1979 | Pages 123-132
Technical Paper | Thorium Fuel Cycle in a Breeder Economy / Fuel Cycle | doi.org/10.13182/NT79-A32142
Articles are hosted by Taylor and Francis Online.
Nuclear nonproliferation considerations have resulted in renewed interest in the thorium fuel cycle. Reactor physics parameters of a typical 1200-MW(electric) fast breeder reactor design were compared for the cases when 233U is substituted for plutonium as a fissile fuel and when 232Th is substituted for 238U as a fertile fuel When the 238U in the blanket is replaced with 232Th, the reactor physics parameters are relatively unchanged. However, replacing 238U in the core with 232Th increases the critical mass by 11 to 15% and decreases the breeding ratio by 0.13 to 0.16. In addition, replacing the plutonium in the core with 233U decreases the critical mass by 4 to 6% and decreases the breeding ratio by 0.13 to 0.16. Both of the changes in the core make the sodium void coefficient more negative.
