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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.
M. D. Freshley
Nuclear Technology | Volume 15 | Number 2 | August 1972 | Pages 125-176
Technical Paper | Plutonium Utilization in Commercial Power Reactors / Reactor | doi.org/10.13182/NT72-A31143
Articles are hosted by Taylor and Francis Online.
The satisfactory irradiation performance of several types of mixed-oxide fuels suitable for the utilization of plutonium in thermal reactors was demonstrated by a significant number of experiments performed in the Plutonium Recycle Test Reactor (PRTR). Heterogeneously and homogeneously enriched packed-particle and pellet mixed-oxide fuels were irradiated at peak linear heat ratings higher, i.e., >655 W/cm (>20 kW/ft), than those employed in the most advanced commercial reactors to significant burnups, i.e., >18 000 MWd/MTM. Early experience in PRTR provided some of the first data related to the effects of hydrogenous impurities on Zircaloy-clad mixed-oxide fuel performance. The demonstrated solution to the problem was achieved through the development of improved analytical and fuel fabrication techniques. Fuel rod cladding becomes oval shaped during irradiation due to creep collapse with the degree of ovality varying among the different fuel types. The fission gas release fraction for vipac mixed-oxide fuels varies linearly from a value of 0.05 for a volumetric average temperature of 600°C to essentially 1.00 for a volumetric average temperature of 2250°C. Homogenization of the PuO2 particles in mechanically mixed UO2-PuO2 commences at fuel temperatures sufficient to cause sintering and equiaxed grain formation during irradiation. PRTR experience indicates that a fuel-cladding reaction that is stoichiometry dependent occurs in Zircaloy-clad mixed-oxide fuels. The satisfactory defect performance of mixed-oxide fuels was demonstrated by several in-service and intentionally defected experiments although there are indications that defect performance may constitute an operating limit at very high linear heat ratings.
