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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Reflections on NOW
Hash Hasemianpresident@ans.org
Last month, I talked about my goal of strengthening ANS’s voice, in part by attending three conferences. I have now checked the first event off that list: the Nuclear Opportunities Workshop.
This year, NOW took another step in outgrowing its “workshop” moniker and transitioning to a full-fledged regional conference and expo. What started only a few years ago as a small gathering in Oak Ridge, Tenn., with roughly 50 attendees has skyrocketed to an event with 1,100 people in attendance in Knoxville.
NOW’s popularity reflected how busy the roughly 350 nuclear companies in Tennessee have been in recent years. There is significant work going on surrounding Gen IV reactor development and deployment, advancements in new nuclear fuels, and defense-related builds like the Uranium Processing Facility.
J. S. Eakins
Nuclear Technology | Volume 168 | Number 3 | December 2009 | Pages 894-898
Shielding | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Protection | doi.org/10.13182/NT09-A9324
Articles are hosted by Taylor and Francis Online.
The transmission of 0.511-MeV photons through concrete, lead, or iron is determined using MCNP4c2, by exposing 50-cm-radius cylinders of the materials to plane parallel sources. Cylinders are modeled with thicknesses up to 50 cm in 5-cm increments for concrete, 10 cm in 1-cm increments for lead, and 20 cm in 2-cm increments for iron. The resulting transmission factors span from 1 to <10-3 for concrete, to almost 10-7 for lead, and to roughly 10-5 for iron. The reliability of the method is checked by performing the calculations for selected thicknesses of material with a 0.662-MeV source and comparing the results against published data. Acceptable agreement is reported in almost all cases.
