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2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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NextEra and Google ink a deal to restart Duane Arnold
A day anticipated by many across the nuclear community has finally arrived: NextEra Energy has officially announced its plans to restart Iowa’s only nuclear power plant, the Duane Arnold Energy Center.
Elias P. Gyftopoulos, Luis de Sobrino
Nuclear Science and Engineering | Volume 6 | Number 2 | August 1959 | Pages 135-139
Technical Paper | doi.org/10.13182/NSE59-A25643
Articles are hosted by Taylor and Francis Online.
The reactivity worth of cylindrical control rods of small cross section inserted in a cylindrical reactor is evaluated by means of a variational method. Both one-group and two-group diffusion theory are used and simple formulae are developed for a single eccentric and a concentric array of control rods. The results obtained are illustrated by means of a numerical example and compared to the results derived from other methods available in the literature.
