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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.
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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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.
C. Sari
Nuclear Technology | Volume 35 | Number 1 | August 1977 | Pages 145-153
Technical Paper | Fuel | doi.org/10.13182/NT77-A31857
Articles are hosted by Taylor and Francis Online.
Temperature gradients similar to those existing in high-rated MX-type fuel [UC, (U,Pu)C and (U, Pu)C0.9 N0.1] have been obtained by heating cylindrical pellets with an alternating electrical current flowing in the axial direction. The power used and the heat impedance existing between the surface of the pellets and the cladding material is sufficient to produce average temperature gradients on the order of 150 kK/m in temperature regions between 1273 and 2273 K. Preliminary experiments show that under these temperature conditions, important restructuring of the MX-type fuel occurs after a comparatively short time (<40 h). Generally, four structural zones, characterized by a temperature and a temperature gradient, have been observed in cross sections of the heated specimens. In the direction of increasing pellet radius (decreasing temperature), one finds a zone with large rounded pores and large equiaxed grains, a zone where pores and grains are elongated in the direction of the temperature gradient, and next to this, a zone with intergranular pores and equiaxed grains, and, finally, an unrestructured zone at the edge of the pellet. Lenticular pores are not responsible for the fuel restructuring. They appear at temperatures around 1773 K, and their apparent migration rate is lower than that observed in uranium-plutonium oxides. The fuel heated in a thermal gradient also shows a general tendency to sinter at temperatures as low as 1523 K and a tendency to crack. The free volume created by the formation of cracks is independent of the initial density of the fuel. Plutonium enrichment at the open and healed cracks and at the surface of the pellets has been observed.