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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.
Luis de Sobrino, Melville Clark, Jr.
Nuclear Science and Engineering | Volume 10 | Number 4 | August 1961 | Pages 384-387
doi.org/10.13182/NSE61-A15383
Articles are hosted by Taylor and Francis Online.
Approximations to the Boltzmann equation including the first two terms in the inverse mass expansion are developed for anisotropic moderators. An asymptotic solution is obtained. The results for beryllium and graphite are compared with the results of the Wilkins approximation. It is seen that this approximation constitutes an improvement over the Wigner and Wilkins gaseous model because the error produced by neglecting higher orders in the inverse mass expansion is in the right direction to account for crystalline binding.
