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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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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.
R. P. Gardner, C. L. Barrett, W. Haq, D. E. Peplow
Nuclear Science and Engineering | Volume 122 | Number 3 | March 1996 | Pages 326-343
Technical Paper | doi.org/10.13182/NSE96-A24168
Articles are hosted by Taylor and Francis Online.
A Monte Carlo code named Mcnaff has been developed and tested for flow rate measurement and general composition determination of a flowing fluid by neutron activation analysis. Specifically, oxygen determination in a flowing fluid is treated, including simulating the emission and transport of neutrons in the fluid, the activation of l6O to 16N, the subsequent flow and dispersion of the 16N in the flow channel, the downstream decay of 16N, and the subsequent detection of the emitted decay gamma rays. This code is very efficient, partly because (a) the continuous single history approach has been taken, which follows a single history from emission of a neutron, through the production and decay of the 16N and the emission of a characteristic gamma ray, and finally to the full energy detection of the gamma ray and (b) the principle of forcing can be and is used throughout so that almost every history results in a partial success. The present Mcnaff code is capable of calculating gamma-ray detection yields per neutron emitted to the same accuracy as an approach by Perez-Griffo, Block, and La hey, which numerically solves the partial differential equations for modeling particle dispersion and diffusion and calculates separately by Monte Carlo both the neutron absorption and gamma-ray detection process. The Mcnaff code is estimated to be about two orders of magnitude faster and should be more convenient to use because all calculations are accomplished in a single step.
