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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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OECD NEA meeting focuses on irradiation experiments
Members of the OECD Nuclear Energy Agency’s Second Framework for Irradiation Experiments (FIDES-II) joint undertaking gathered from September 29 to October 3 in Ketchum, Idaho, for the technical advisory group and governing board meetings hosted by Idaho National Laboratory. The FIDES-II Framework aims to ensure and foster competences in experimental nuclear fuel and structural materials in-reactor experiments through a diverse set of Joint Experimental Programs (JEEPs).
John C. Lee, Sin Tao Hsue
Nuclear Technology | Volume 76 | Number 2 | February 1987 | Pages 203-208
Technical Paper | Fuel Cycle | doi.org/10.13182/NT87-A33874
Articles are hosted by Taylor and Francis Online.
Based on a simplified solution of the balance equations for concentration of uranium and plutonium isotopes and a set of two-group microscopic cross sections, isotopic ratios, 235U/U, Pu/U, and 239Pu/235U, are calculated as a function of fuel burnup for pressurized water reactor spent fuel. The two-group cross sections for 235U, 238U, 239Pu, and water are collapsed into equivalent thermal-group constants, with the fast-to-thermal flux ratio obtained through a two-group criticality consideration. For this purpose, parasitic neutron captures are represented through a simple semiempirical relationship. The calculational model, incorporated as the BURN code, yields isotopic ratios that compare favorably with three major data sets from the ISTLIB data bank.
