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Conference Spotlight
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.
Gilberto Espinosa-Paredes, Marco Antonio Polo-Labarrios
Nuclear Science and Engineering | Volume 171 | Number 3 | July 2012 | Pages 258-264
Technical Note | doi.org/10.13182/NSE11-58
Articles are hosted by Taylor and Francis Online.
In this technical note we develop a new approximation from the solution of the time-dependent Boltzmann equation, which includes a fractional constitutive equation of the neutron current density, for a general medium. The fractional constitutive equation in combination with the conservation law that governs the particle collision and reaction processes (P1) approximation for the transport equation gives a time-fractional telegrapher's equation (TFTE). The wave velocity found with this approximation is 3-/2 for < 1. The numerical results are compared with the exact solution and Heizler's approximation. We found that the TFTE gives the best estimate for a purely absorbing medium, where most approximations fail. The asymptotic diffusion coefficient was applied for a heterogeneous medium, and the results show that the behavior of the TFTE improves.