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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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A wave of new U.S.-U.K. deals ahead of Trump’s state visit
President Trump will arrive in the United Kingdom this week for a state visit that promises to include the usual pomp and ceremony alongside the signing of a landmark new agreement on U.S.-U.K. nuclear collaboration.
N. Spinks
Nuclear Science and Engineering | Volume 22 | Number 1 | May 1965 | Pages 87-93
Technical Paper | doi.org/10.13182/NSE65-A19765
Articles are hosted by Taylor and Francis Online.
The extrapolation distance ϵ at the surface of a grey cylindrical control rod of given size is found in terms of the blackness β of the rod and in terms of the extrapolation distance ϵb at the surface of a black rod of the same size. The formula is where λe is the transport mean free path in the region external to the rod. Tables are provided for β and an empirical expression for ϵb/λe is given.
