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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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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.
G. S. Brunson, E. N. Pettitt, and R. D. McCurdy
Nuclear Science and Engineering | Volume 1 | Number 2 | May 1956 | Pages 174-184
Technical Paper | doi.org/10.13182/NSE56-A17521
Articles are hosted by Taylor and Francis Online.
Delayed neutron studies have been made in the Experimental Breeder Reactor (EBR), using a conventional sample transfer system and a neutron counter comprised of BF3 tubes in a graphite geometry. Samples of Th, U233, U235, U238, and Pu were irradiated in a fast flux; samples of U233, U235, and Pu in a thermal flux. The ratio of the delayed neutron yield per fission (based on the longest four periods) to the delayed neutron yield per fast fission of U235 was determined as: for fast fission of U233, 0.414 ± 7.5%; for fast fission of Pu, 0.405± 7.5%; for fast fission of Th, 3.09 ± 17%; for fast fission of U238, 2.23 ± 7.5%. The ratio of fast fission to thermal fission delayed neutron yields was not significantly different from unity for all samples except Pu, where the ratio of thermal to fast fission yields was 0.888 ± 6%. This latter is believed to be primarily attributable to the 5% fraction of Pu240 in the sample.
