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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
Ely M. Gelbard, Raymond P. Hughes
Nuclear Science and Engineering | Volume 70 | Number 3 | June 1979 | Pages 262-273
Technical Paper | doi.org/10.13182/NSE79-A20147
Articles are hosted by Taylor and Francis Online.
In earlier work by Gelbard and Lell, arguments based on perturbation theory were used to obtain relations between mean-square chord lengths and lattice eigenvalues for given bucklings. We show here that first-order perturbation theory does not give the lattice eigenvalue correctly to order B2. When all missing terms in B2 are inserted, the eigenvalue buckling relations remain formally unchanged, but the mean-square chord lengths must be redefined. The original and redefined mean-square chord lengths differ only insofar as events in successive fission generations are correlated. A reexamination of work based on the original relations indicates that earlier numerical results were substantially correct.