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2025 ANS Winter Conference & Expo
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.
Ming Wang, Jinxing Zheng, Yuntao Song, Xianhu Zeng, Ming Li, Wuquan Zhang, Pengyu Wang, Junsong Shen
Nuclear Technology | Volume 206 | Number 5 | May 2020 | Pages 779-790
Technical Paper | doi.org/10.1080/00295450.2019.1670011
Articles are hosted by Taylor and Francis Online.
The superconducting isochronous cyclotron SC200 for proton therapy is under development in Hefei, and the active scanning method has been selected as the beam delivery technology. To reduce energy loss and transverse scattering of the proton beam, a gas chamber in the pencil beam scanning (PBS) nozzle has been designed to shorten the length of the air segment. To determine whether using a helium filling gas or vacuum is the most suitable for the SC200 PBS nozzle, the beam size and the energy loss at the isocenter and the dose distribution in the water phantom are compared using the TOol for PArticle Simulation (TOPAS) code. The results show that using the helium filling gas resulted in scattering and energy loss of the proton beam compared with using vacuum, but these effects were minimal. Considering the disadvantages of the engineering problems of creating a vacuum chamber, helium was selected as the filling gas for the PBS nozzle chamber. Moreover, the following parameters were analyzed and optimized: gas pressure, gas purity, and film thickness of the chamber. When the helium pressure was below 1.1 atm and the air proportion was less than 5%, the beam size at the lowest energy of the proton beam at the isocenter was lower than 8 mm, meeting the clinical requirements.