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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.
J. T. Mihalczo
Nuclear Science and Engineering | Volume 49 | Number 4 | December 1972 | Pages 489-504
Technical Paper | doi.org/10.13182/NSE72-A22568
Articles are hosted by Taylor and Francis Online.
Cylinders and cylindrical annuli of uranium metal (93.15 wt% 235U), with diameters varying from 7 to 15 in., were assembled to delayed criticality with graphite reflectors varying in thickness up to 18 in. or with an effectively infinite thickness polyethylene on all outer surfaces. In one series of measurements a polyethylene reflector was also placed adjacent to only one flat surface of the cylinders. The multiplication factor calculated by both Sn transport and Monte Carlo methods, with various sets of cross sections agreed very well with the experimental values. As a result of the high order of Sn and the large number of spatial intervals required, the computing time for the transport theory calculations was a factor of 10 larger than that required for the Monte Carlo calculations with standard deviations of 1%.
