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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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FPoliSolutions demonstrates RISE, an RIPB systems engineering tool
The American Nuclear Society’s Risk-informed, Performance-based Principles and Policy Committee (RP3C) has held another presentation in its monthly Community of Practice (CoP) series. Former RP3C chair N. Prasad Kadambi opened the October 3 meeting with brief introductory remarks about the RP3C and the need for new approaches to nuclear design that go beyond conventional and deterministic methods. He then welcomed this month’s speakers: Mike Mankosa, a project engineer at FPoliSolutions, and Cesare Frepoli, the company’s president, who together presented “Introduction to RISE: A Digital Framework for Maintaining a Risk-Informed Safety Case for Current and Next Generation Nuclear Power Plants.”
Watch the full webinar here.
Trygve E. Eriksen
Nuclear Technology | Volume 70 | Number 2 | August 1985 | Pages 261-267
Technical Paper | Radioactive Waste Management | doi.org/10.13182/NT85-A33651
Articles are hosted by Taylor and Francis Online.
Migration of I52Eu(III), 235Np(V), 237Pu(IV), 241Am(III), 99Tc(VII), and 99Tc(IV) was studied in natural fissures oriented parallel to the axis of granitic drill cores. A pulse of radionuclide solution was injected at one end of the fissure and the temporal change in radionuclide concentration of the effluent measured. At the end of each experiment the fissure was opened and the radionuclide distribution on the fissure surfaces measured. The radionuclide distribution ratios Ra, calculated from the measured retardation, correlate well to published distribution coefficients Kd. The increase in retardation of 235Np with increasing pH in the pH range 6 to 9 is in accordance with the hydrolytic equilibrium NpO2+ + OH‾ ⇄ NpO2(OH). Reduction of Tc(VII) to Tc(IV) resulted in a marked increase in retardation.
