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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.
János Gadó, István Vidovszky
Nuclear Science and Engineering | Volume 104 | Number 3 | March 1990 | Pages 217-221
Technical Paper | doi.org/10.13182/NSE90-A23721
Articles are hosted by Taylor and Francis Online.
Changes in the sign of the reactivity coefficient due to changes in the water density are very important in all water-moderated lattices. This sign is determined by the lattice parameters, such as the fuel enrichment and the lattice pitch. It is, of course, negative in undermoderated lattices. However, in special lattices, for example, in spent-fuel storage pools, this reactivity coefficient could be positive, even though one would predict a negative value from the lattice parameters. An example of this effect is presented, and the unexpected sign is explained.