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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.
Jakob Weitman
Nuclear Science and Engineering | Volume 18 | Number 2 | February 1964 | Pages 246-259
Technical Paper | doi.org/10.13182/NSE64-A18325
Articles are hosted by Taylor and Francis Online.
The effective resonance integral of thorium oxide rods has been determined as a function of their surface-to-mass ratio. The range of S/M values covered is 0.15 - 0.65 cm2/g. An experimental technique based on the comparison of activities obtained in thermal and slowing-down neutron fluxes was employed. The shape of the resonance neutron spectrum was determined from measurements with a fast chopper and from calculations, permitting deduction of a correction factor which relates the experimental values to the ideal 1/E case. The results are summarized by the following expression: The main contribution to the margin of error arises from the uncertainties in the 4% spectral correction applied, in the 1.5 b “l/v” part deducted and in the 1510 b infinite-dilution integral of gold, used as a standard. In order to compare the consistency of Dresner's first equivalence theorem and Nordheim's numerical calculations relative to our results, the resonance integral values for thorium metal rods obtained previously by Hellstrand and Weitman have been recalculated, using recent cross section and spectrum data. The new formula is It differs from the old one mainly because of the proved non-l/v behaviour of the thorium cross section below the first resonance.