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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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April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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NRC approves subsequent license renewal for Oconee
All three units at the Duke Energy’s Oconee nuclear power plant in South Carolina are now licensed to operate for an additional 20 years.
Gregory K. Miller, Derek C. Wadsworth
Nuclear Technology | Volume 110 | Number 3 | June 1995 | Pages 396-406
Technical Paper | Actinide Burning and Transmutation Special / Nuclear Fuel Cycle | doi.org/10.13182/NT95-A35109
Articles are hosted by Taylor and Francis Online.
The prototypical nuclear fuel of the New Production Modular High-Temperature Gas-Cooled Reactor (NP-MHTGR) consists of spherical TRISO-coated particles suspended in graphite cylinders. The coating layers surrounding the fuel kernels consist of pyrolytic carbon layers and a silicon carbide (SiC) layer. These coating layers act as a pressure vessel that retains fission product gases. The structural integrity of this pressure vessel relies on the strength of the SiC layer. If the SiC fractures because of the internal pressure loading, then the particle fails. Results obtained from a series of crush tests on unirradiated fuel particles were used to estimate the strength of the SiC layer for internal pressure loading. The SiC strength for a particle was defined in terms of the maximum stress level in the SiC layer at which the particle failed. The transformations between the test results, which involve compressive crushing loads, and the internal pressure loadings experienced in NP-MHTGR reactor conditions were made utilizing the Weibull statistical theory. The test results were also used to estimate failure probabilities for fuel particles that are lacking an outer pyrolytic carbon layer (OPyC). The transformation from the crush test failure data to equivalent SiC strengths under an internal pressure load allowed for a direct comparison in strengths between fully coated particles and particles that lack the OPyC layer. In the latter case, the OPyC has typically been removed through a “burn-back”process. Results showed that strengths for fully coated particles are somewhat higher than for burned-back particles. Whether this is attributable to an actual loss of strength because of the burn-back process or is an artifact of the testing process is a subject for further study. Other effects on particle strength measured by making similar comparisons were particle compacting and particle flaws (large “gold spots”). These generally did not have a significant effect on SiC strengths. Another finding from calculations performed was that application of a “spread ring” load rather than a concentrated “point” load in the crush tests was more representative of the internal pressure loading experienced in NP-MHTGR reactor conditions. Results of the failure probability calculations showed that the failure probability for a batch of burned-back fuel particles was governed by a weak “tail” group of particles, which constitute a small percentage of the total particle batch.