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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
Noel Corngold
Nuclear Science and Engineering | Volume 102 | Number 1 | May 1989 | Pages 114-118
Technical Note | doi.org/10.13182/NSE89-A23635
Articles are hosted by Taylor and Francis Online.
The time-dependent slowing down of neutrons in noncapturing media depends in an important way on how the energy-dependent mean-free-time between scatterings behaves as E → 0. For example, if the mean-free-time decreases, i.e., ν∑s increases, as any positive power of E, the integrated density of neutrons does not remain constant in time. This anomalous behavior is discussed, noting both analogies in other physical processes and early references to the phenomenon of “nonconservation.” The analysis uses some unfamiliar solutions for slowing down in hydrogen, when the cross section has power-law variation; however, the general discussion is not limited to the equal mass case.