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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.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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June 2025
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Latest News
Zaporizhzhia ‘extremely fragile’ relying on single off-site power line, IAEA warns
Europe’s largest nuclear power plant has just one remaining power line for essential nuclear safety and security functions, compared with its original 10 functional lines before the military conflict with Russia, warned Rafael Mariano Grossi, director general of the International Atomic Energy Agency.
C. Coquelet-Pascal, M. Tiphine, G. Krivtchik, D. Freynet, C. Cany, R. Eschbach, C. Chabert
Nuclear Technology | Volume 192 | Number 2 | November 2015 | Pages 91-110
Technical Paper | Fission Reactors | doi.org/10.13182/NT15-20
Articles are hosted by Taylor and Francis Online.
Nuclear systems, composed of reactors with varied fuel and cycle facilities (enrichment plant, fabrication plant, reprocessing plant, etc.), are complex and in constant evolution. Since 1985, the CEA has been developing the simulation software COSI to study different trajectories of nuclear fleet evolution and provide technical elements to decision makers. The principle of COSI, including the typical composition of the data set, is exposed. To evaluate as accurately as possible the isotopic compositions of materials, several physical models are implemented in COSI. The main ones, the evolution calculation and the equivalence models, are described in detail. An exercise of validation of COSI carried out on the French pressurized water reactor (PWR) historical nuclear fleet until 2010 is also presented, as well as a methodology for propagation of input uncertainties on COSI results.
To illustrate the possibilities of COSI, the results of different scenarios studied in the framework of the French Act for Waste Management are discussed. The objective of these scenarios is to evaluate the feasibility of sodium-cooled fast reactor (SFR) deployment to renew the French PWR fleet on different timescales and to analyze the costs and the benefits of different options of minor actinide (MA) partitioning and transmutation. The impacts of SFR deployment on cycle facilities such as the fabrication plant, the spent fuel storage, and the reprocessing plant are minimized. The SFR deployment appears to be feasible with regard to fissile material availability, with an adaptation of fuel cooling time before reprocessing or of SFR breeding gain.
Minor actinide transmutation in homogeneous mode MA diluted in core) and transmutation in heterogeneous mode (in MA-bearing blankets) are compared not only according to their impacts on cycle facilities and on ultimate waste but also according to the reduction of their inventories. The increases in fresh fuel thermal power and spent fuel decay heat due to the addition of MAs in fuels are quantified. The cases of transmutation of all MAs (americium, neptunium, and curium) and of americium only are distinguished. Alternative scenarios are explored to overcome the challenges associated with each option: reduction of the maximal MA content in fresh SFR fuel in the case of homogeneous transmutation and reduction of interim MA storage in the case of heterogeneous transmutation.