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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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Nuclear News 40 Under 40—2025
Last year, we proudly launched the inaugural Nuclear News 40 Under 40 list to shine a spotlight on the exceptional young professionals driving the nuclear sector forward as the nuclear community faces a dramatic generational shift. We weren’t sure how a second list would go over, but once again, our members resoundingly answered the call, confirming what we already knew: The nuclear community is bursting with vision, talent, and extraordinary dedication.
Bret Patrick van den Akker (ORNL)
Proceedings | 16th International High-Level Radioactive Waste Management Conference (IHLRWM 2017) | Charlotte, NC, April 9-13, 2017 | Pages 615-621
We present the analytical solution to the one-dimensional radionuclide transport equation in Laplace transform space. Our model accommodates an arbitrary-length decay chain, an arbitrary combination of host rocks (i.e., an arbitrary combination of multiply fractured and porous transport segments), and a flexible source term (i.e., an arbitrary time-dependent release mode at the entrance point to the series of transport segments). The Laplace transformed analytical solution can be numerically inverted to obtain the time-dependent concentration of the radionuclides of interest at an arbitrary down gradient location. This represents an extension of the previously1 developed model to include the feature of hydrodynamic longitudinal dispersion. This additional feature is important because hydrodynamic dispersion is known to reduce the time of first arrival in radionuclide transport models. Increased fidelity in transport pathway calculations is important for reliable performance assessment for the geological disposal of spent nuclear fuels.