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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. E. Rivarola, P. C. Florido, D. O. Brasnarof, K. H. Kyung, L. Juanicó, J. Bergallo, J. Gonzalez, H. Daverio
Nuclear Technology | Volume 154 | Number 3 | June 2006 | Pages 361-373
Technical Paper | Enrichment | doi.org/10.13182/NT06-A3740
Articles are hosted by Taylor and Francis Online.
The SIGMA technology, a patented new concept for uranium enrichment based on the well-known gaseous diffusion (GD) method, has been developed by the Comisión Nacional de Energia Atómica in Argentina to be an alternative to compete in the uranium enrichment market. The SIGMA engineering approach stands on the integration of several GD stages in one module, with all the stages sharing one single multiflux compressor, one vessel, and a gas turbine. This arrangement, together with the use of the double-diffuser cascade configuration to increase the separative gain, leads to a breakthrough in the capital cost structure of the GD technology and a significant reduction in the energetic and operation costs. With the SIGMA concept, a leveled separative work unit cost that could be almost half the price of the present enrichment market level can be achieved. The SIGMA technology has also been conceived to incorporate proliferation-resistant features, and it has a very small overall proliferation risk. In this work we present the main features of the SIGMA technology, and we formulate a calculation scheme for the overall design analysis. We present some of the results of this investigation, including the SIGMA scale economy, and its comparison with others enrichment technologies.
