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Division Spotlight
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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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
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Peter Hofmann, Siegfried J. L. Hagen, Volker Noack, Gerhard Schanz, Leo K. Sepold
Nuclear Technology | Volume 118 | Number 3 | June 1997 | Pages 200-224
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT118-200
Articles are hosted by Taylor and Francis Online.
Integral experiments with 2-m-long pressurized water reactor and boiling water reactor fuel rod bundle simulators containing a maximum of 57 rods (the CORA experimental program) as well as comprehensive single-effects investigations are examined. The physico-chemical material behavior of light water reactor fuel elements up to ∼2700 K under flowing steam is described. Of particular importance is the determination of critical temperatures above which liquid phases form as a result of chemical interactions between the fuel element components and their influence on damage propagation. The results of the experiments show that low-temperature liquid phases form as early as ∼1300 K as a result of chemical interactions of INCONEL grid spacers with the Zircaloy cladding tube, of the absorber materials (Ag-In-Cd) with Zircaloy, and of boron carbide with stainless steel; however, extensive propagation of these interactions over large distances occurs only above 1550 K. Uranium oxide (UO2) fuel can be liquefied (dissolved) by molten metallic Zircaloy, with the formation of a U-Zr-O melt resulting in UO2 relocation. This process can even take place below the melting point of Zircaloy (2040 K) if the melt, generated by chemical reactions with the various core components, contains metallic zirconium. Beyond the melting point of Zircaloy (≥2040 K), the metallic melt dissolves UO2 more strongly; i.e., at a given time, more UO2 is dissolved. In this case, UO2 relocation occurs ∼1000 K below its melting point. The molten materials form coolant channel blockages (crusts) on solidification. In the CORA experimental facility, temperatures necessary to melt the remaining solid ceramic materials, up to ∼3150 K (according to the U-Zr-O phase diagram), were not attained. On the basis of the experimental results and thermodynamic considerations, three distinct temperature regimes can be defined where liquid phases that form in the reactor core give rise to substantial material relocations and different degrees of core damage. Quenching of an overheated fuel element with water from the bottom (simulating flooding of an uncovered reactor core) initially gives rise to further heating of the bundle components as a result of intensive oxidation of metallic constituents, which is associated with the formation of local melts and the additional generation of considerable amounts of hydrogen within a very short period of time.
