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Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
G. C. Pomraning
Nuclear Science and Engineering | Volume 24 | Number 3 | March 1966 | Pages 291-301
Technical Paper | doi.org/10.13182/NSE66-A17641
Articles are hosted by Taylor and Francis Online.
The variational method and region-balance method, both special cases of the more general method of weighted residuals, are each used as the formalism to develop a spatial expansion of the diffusion equation for two problems. These are 1)a spatially dependent spectrum problem for the purpose of computing the self-shielding in the 240Pu resonance and 2) a simple one-dimensional eigenvalue problem. In both instances numerical results indicate that the variational method is more accurate than the region-balance method. Of particular interest is the variational spatial-expansion approach to the eigenvalue problem. This may be a useful method for deriving a set of difference equations for the multigroup diffusion equation in that it should lead to an accurate representation of the flux with a relatively small number of mesh points.