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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has since been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that Unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. local time on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
A. Poulesquen, C. Jégou
Nuclear Technology | Volume 160 | Number 3 | December 2007 | Pages 337-345
Technical Paper | Materials for Nuclear Systems | doi.org/10.13182/NT07-A3904
Articles are hosted by Taylor and Francis Online.
A combined transport and radiolysis model is proposed in this paper to predict the oxidation/dissolution of UO2 under alpha radiolysis of water. The UO2-water interface is divided into an arbitrary number of layers. The Chemsimul kinetic code is used for radiolysis calculations in each layer, and the modeling of transport between the layers is based on Fick's law. The calculation proceeds in an iterative way, and an alpha dose rate profile is taken into account as input data. To limit the calculation time, which depends on the computer capacity and the duration of the leaching experiment described, a compromise between the thickness and the number of cells has to be found. At present, simulations of leaching experiments lasting several days cannot be carried out because of the very long calculation time. However, the calculation has been compared with experimental results obtained under irradiation at high flux levels of a UO2-water interface subjected to a beam of He2+ particles generated by a cyclotron. Owing to computer time limitation, calculations are carried out by considering 200 layers, each 10 m thick, to simulate 1-h experiments. In the experimental geometry (monoenergetic linear alpha beam), the alpha dose rate profile is well described by a summation of Bragg curves. The comparison relates to experiments performed in aerated and deaerated media at a high flux of 3.3 × 1010 cm-2s-1 and 3.3 × 1011 cm-2s-1. The calculated uranium content in solution is three times lower than the experimental value, and the hydrogen peroxide concentration is ten times lower in aerated media. In deaerated media, however, the comparison is quite good. Finally, a calculation was carried out with a large imposed dissolved hydrogen concentration in solution to check the inhibition of matrix dissolution. The release of uranium in solution is relatively high despite the hydrogen concentration in solution because of the primary formation of hydrogen peroxide. This is probably because of a lack of knowledge concerning the inhibitor mechanism under alpha radiolysis (influence of the surface under alpha irradiation, hydrogen activation, validity of primary radiolytic yield in presence of H2, etc.), which is not taken into account in our calculations.