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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.
Feroz Ahmed, L. S. Kothari, Ashok Kumar
Nuclear Science and Engineering | Volume 46 | Number 2 | November 1971 | Pages 203-213
Technical Paper | doi.org/10.13182/NSE71-A22354
Articles are hosted by Taylor and Francis Online.
The dependence of neutron diffusion length on the size and shape of the cross-sectional area of infinitely long rectangular blocks of crystalline moderators (graphite and beryllium) has been studied using an energy-dependent transverse buckling. In conformity with the experimental results in graphite, the diffusion length is found to increase with a decrease in the transverse size of the assembly. It is further found that in assemblies with small transverse dimensions, pseudoequilibrium conditions are established fairly rapidly and reasons for this are discussed. On the other hand, in assemblies with intermediate transverse dimensions (cross-sectional area lying between 70 × 70 cm2 and 50 × 50 cm2 for graphite and between 30 × 30 cm2 and 20 × 20 cm2 for beryllium), even pseudo-equilibrium conditions are not established at very large distances from the source. Dependence of the diffusion length on the shape of the cross-sectional area is also investigated.