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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Hash Hashemian: Visionary leadership
As Dr. Hashem M. “Hash” Hashemian prepares to step into his term as President of the American Nuclear Society, he is clear that he wants to make the most of this unique moment.
A groundswell in public approval of nuclear is finding a home in growing governmental support that is backed by a tailwind of technological innovation. “Now is a good time to be in nuclear,” Hashemian said, as he explained the criticality of this moment and what he hoped to accomplish as president.
F. Malvagi, G. C. Pomraning, M. Sammartino
Nuclear Science and Engineering | Volume 112 | Number 3 | November 1992 | Pages 199-214
Technical Paper | doi.org/10.13182/NSE92-A29069
Articles are hosted by Taylor and Francis Online.
We consider the problem of neutral particle transport in a stochastic Markovian mixture consisting of an arbitrary number M of immiscible fluids. The Liouville master equation is used to obtain a model for the ensemble-averaged angular flux. This model consists of M coupled transport equations. If the absorption, internal source, and temporal and spatial gradients are assumed small, this transport description can be reduced to a diffusive description. Depending upon the scaling of the Markovian transition lengths, this diffusive limit consists of either a single diffusion equation or a set of M coupled diffusion equations. The asymptotic analysis is also used to derive appropriate initial and boundary conditions for each diffusion equation.