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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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The journey of the U.S. fuel cycle
Craig Piercycpiercy@ans.org
While most big journeys begin with a clear objective, they rarely start with an exact knowledge of the route. When commissioning the Lewis and Clark expedition in 1803, President Thomas Jefferson didn’t provide specific “turn right at the big mountain” directions to the Corps of Discovery. He gave goal-oriented instructions: explore the Missouri River, find its source, search for a transcontinental water route to the Pacific, and build scientific and cultural knowledge along the way.
Jefferson left it up to Lewis and Clark to turn his broad, geopolitically motivated guidance into gritty reality.
Similarly, U.S. nuclear policy has begun a journey toward closing the U.S. nuclear fuel cycle. There is a clear signal of support for recycling from the Trump administration, along with growing bipartisan excitement in Congress. Yet the precise path remains unclear.
Richard E. Faw, J. Kenneth Shultis
Nuclear Science and Engineering | Volume 114 | Number 1 | May 1993 | Pages 76-80
Technical Notes | doi.org/10.13182/NSE93-A24016
Articles are hosted by Taylor and Francis Online.
Buildup factors are reported for the absorbed dose in air resulting from point isotropic sources of monoenergetic photons with energies from 10 to 100 MeV. Factors were calculated from photon fluences computed by the EGS4 code for coupled photon and electron transport. Comparisons are made with results of moments method calculations and with buildup factors computed directly from localized energy absorption.
