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Conference Spotlight
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.
M. M. R. Williams
Nuclear Science and Engineering | Volume 18 | Number 2 | February 1964 | Pages 260-270
Technical Paper | doi.org/10.13182/NSE64-A18326
Articles are hosted by Taylor and Francis Online.
An exact solution to the energy-dependent Milne problem for isotropic scattering has been obtained using a simple separable scattering kernel. The extrapolation distance and angular distribution at the surface of the half-space have been calculated using the free-gas scattering cross sections. A further calculation for a very narrow kernel shows that the extrapolation distance is insensitive to the inelastic part of the scattering kernel, but depends mainly on the energy dependence of the mean free path. The results have been compared with numerical work obtained from the THERMOS code and thus provide a measure of the accuracy of THERMOS for this type of problem. The results also give physically reasonable bounds on the extrapolation distance and angular distributions.
