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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.
Dan M. Goebel
Fusion Science and Technology | Volume 10 | Number 3 | November 1986 | Pages 761-769
Impurity Control | Proceedings of the Seveth Topical Meeting on the Technology of Fusion Energy (Reno, Nevada, June 15–19, 1986) | doi.org/10.13182/FST86-A24832
Articles are hosted by Taylor and Francis Online.
Particle removal from tokamak plasmas is essential to achieve density control and some measure of impurity control. This requirement can be satisfied by pump limiters, the present status of which is reviewed here. Modular experiments have recently achieved particle removal rates over 10 torr-1/sec. Studies of impurity removal by pump limiters have demonstrated He and N2 (moderate Z) exhaust. Successful modeling of the pump limiter performance using Monte-Carlo neutral gas codes has expanded the understanding of the physics of pump limiters. The heat flux to the surface of limiters in tokamaks has been studied in detail. The rapid progress in the engineering, theory, and experimental results of pump limiters has led to plans for the application of these devices in new experiments in the next few years.
