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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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Fusion Science and Technology
Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
R.-D. Penzhorn, Y. Torikai, S. Naoe, K. Akaishi, A. Perevezentsev, K. Watanabe, M. Matsuyama
Fusion Science and Technology | Volume 57 | Number 3 | April 2010 | Pages 185-195
Technical Paper | doi.org/10.13182/FST57-3-185
Articles are hosted by Taylor and Francis Online.
Exposure of Type 316 stainless steel to tritium-containing hydrogen at an elevated temperature causes diffusion of the majority into the bulk and trapping of a small fraction in a thin oxide layer on the surface at concentrations far exceeding those in the bulk. The uptake by the bulk and surface layer is temperature and pressure dependent. After chemical erosion of the tritium-rich layer, the concentration of tritium on the topmost surface is slowly and asymptotically restored even at 298 K. Isothermal heating at 373 or 473 K until substantial release of the bulk tritium is associated with a comparatively much smaller liberation from the surface layer suggesting different retention and liberation mechanisms. The tritium inventory and profile evolution of homogeneously loaded Type 316 stainless steel caused by chronic release at the ambient temperature and radioactive decay were followed experimentally over several years and modeled successfully by a diffusion mechanism. The model has been adapted to specimens nonhomogeneously loaded with tritium only up to the subsurface. It simulates profile and inventory changes well even after prolonged aging. Chronic release constitutes an aging loss of tritium comparable to that of radioactive decay that should be taken into account for the assessment of tritium-contaminated stainless steel waste.