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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Fusion Science and Technology
October 2025
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.
Stephan Letts, Evelyn Fearon, Mitchell Anthamatten, Steven Buckley, Charlotte King, Robert Cook
Fusion Science and Technology | Volume 49 | Number 4 | May 2006 | Pages 714-720
Technical Paper | Target Fabrication | doi.org/10.13182/FST06-A1191
Articles are hosted by Taylor and Francis Online.
We completed the development of a method for preparing smooth vapor-deposited polyimide ablators up to 160 m thick for NIF target capsules. The process consists of two steps. The first step is vacuum chemical vapor deposition of monomer species, pyromellitic dianhydride and 4,4'-oxidianiline, onto the surface of a spherical shell mandrel where they may react to form polyamic acid. In the second step dimethyl sulfoxide (DMSO) vapor exposure in a gas-levitation smoothing apparatus swells and fluidizes the outer surface. Roughness in the outer fluid layer is reduced by surface-tension-driven flow. The shells are cured in the final smoothing step by heating to 300°C, converting the polyamic acid to polyimide. Recent experiments using X-ray radiography have allowed us to determine the depth of solvent penetration and the solvent concentration over a range of solvent exposure conditions. We found that the rate of penetration is a function of the solvent partial pressure in the flowing vapor stream. The concentration of solvent in the swollen layer is ~0.43 g/cm3 and is independent of exposure conditions. Using the penetration information we were able to improve the smoothing process by increasing the solvent partial pressure. The optimized vapor smoothing process allowed us to consistently meet the surface smoothness specifications of NIF capsules.
