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November 9–12, 2025
Washington, DC|Washington Hilton
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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 Technology | Volume 159 | Number 2 | August 2007 | Pages 119-133
Technical Paper | Fission Reactors | doi.org/10.13182/NT07-A3859
Articles are hosted by Taylor and Francis Online.
In this paper passive reactivity control devices for a Generation IV gas-cooled fast reactor (GCFR) are discussed. The proposed devices use liquid 6Li as absorber. The device is triggered by a freeze seal, and upon activation the 6Li is irreversibly introduced into the core region by pressure differences. The device is dubbed the lithium injection module (LIM). Transient thermohydraulic calculations were done using the CATHARE2 code on a simplified thermohydraulic model of GFR600, a 600-MW(thermal) GCFR investigated in the scope of the European GCFR-STREP. The thermohydraulic model uses an accurate model of the ceramic fuel plates and includes natural convection decay heat removal circuits. To properly account for power production during the transient, a synthetic decay power curve was made based on the ANSI/ANS-5.1-1994 law. Loss-of-flow and control rod withdrawal/ejection transients are presented. Neutronic calculations show that the LIMs have a low reactivity worth between -2.1 and -1.5 $. In spite of their low worth, the LIMs are capable of keeping the reactor power bounded during all calculated transients. Shutdown is not always achieved, depending on the kind of transient under consideration. For pressurized loss of flow, recriticality due to Doppler feedback may become problematic in the natural-circulation phase. For rapid control rod ejections, the resulting very fast power transients cause concern for material degradation. One LIM would be enough to control reactor power, but redundancy may call for more than one LIM in the core.
