ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
Standards Program
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!
Latest Magazine Issues
Sep 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
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.
W. R. Marcum, T. S. Palmer, B. G. Woods, S. T. Keller, S. R. Reese, M. R. Hartman
Nuclear Science and Engineering | Volume 171 | Number 2 | June 2012 | Pages 150-164
Technical Paper | doi.org/10.13182/NSE11-25
Articles are hosted by Taylor and Francis Online.
The Oregon State TRIGA Reactor (OSTR) was converted from highly enriched uranium (HEU) Fuel Life Improvement Program (FLIP) fuel to low-enriched uranium (LEU) fuel in October 2008. This effort was driven by the U.S. Department of Energy's Reduced Enrichment for Research and Test Reactor program. The new LEU fuel is 30/20 U-Zr1.6H (30% uranium in the fuel matrix, 19.75 wt% enriched) in contrast to the FLIP fuel having U-Zr1.6H (8.5% uranium in the fuel matrix, 70 wt% enriched). This new fuel composition provides the best match in performance of the available mixture ratios when compared to the previous FLIP fuel. To support conversion, a complete assessment and reevaluation of the OSTR Safety Analysis Report was performed. This evaluation included steady-state thermal-hydraulic and neutronics characterizations of the HEU and LEU cores as well as a transient behavior (pulse) analysis of both core types.This paper presents a summary of the methods used and results produced during the pulse analysis identifying power, temperature, and reactivity during pulsed operation for the FLIP and new LEU fuel. This analysis was performed using RELAP5-3D version 2.4.2 and point reactor kinetics simulation software; these two methods are found to agree very well. We discuss the differences between the two fuels and the impact of pulse behavior on the safety limits for the converted reactor.
