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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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ANS names 2026 Congressional Fellows
Kasper
Hayes
The American Nuclear Society has officially selected two of its members to serve as its 2026 Glenn T. Seaborg Congressional Science and Engineering Fellows. Alyssa Hayes and Benjamin Kasper will help the Society fulfill its strategic goal of enhancing nuclear policy by working in the halls of Congress, either in a congressional member’s personal office or with a committee, starting next January.
“The Congressional Fellowship program has put ANS in a unique position to provide significant technical assistance to Congress on nuclear science, energy, and technology, with great results,” said Congressional Fellowship Special Committee chair Harsh Desai, himself a former Congressional Fellow. “This once-in-a-lifetime professional development opportunity will allow them to learn the art of policymaking and potentially pursue it as part of their careers beyond the fellowship.”
Ramiro Pareja, Nieves De Diego, Rosa Maria De La Cruz, Javier Del Río
Nuclear Technology | Volume 104 | Number 1 | October 1993 | Pages 52-63
Technical Paper | Material | doi.org/10.13182/NT93-A34869
Articles are hosted by Taylor and Francis Online.
Positron lifetime and microhardness measurements have been performed on untreated, thermal-aged, neutron-irradiated, and postirradiation-annealed samples of reactor pressure vessel steels with the purpose of investigating the mechanisms of irradiation-induced hardening and recovery of the mechanical properties in these materials. The positron lifetime experiments have not revealed any evidence of the formation of a significant concentration of voids or vacancy clusters in samples irradiated at ∼290°C with fluences ≤2.71 × 1023 n/m2 (E > 1 MeV), but they suggest a dislocation annealing induced by the irradiation. Isochronal annealing experiments with neutron-irradiated samples show a simultaneous recovery in their positron lifetime and microhardness at ∼340°C. From the microhardness measurements, the yield strength of the irradiated material has been estimated. The results appear to be consistent with a model of hardening due to irradiation-induced dissolution of precipitates with formation of small metastable precipitates after postirradiation aging and recovery induced by the disappearance of these metastable precipitates.
