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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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Latest News
EPA administrator Lee Zeldin talks the future of nuclear
In a recent interview on New York radio station 77 WABC, administrator of the Environmental Protection Agency Lee Zeldin talked with host John Catsimatidis about the near-term future of the domestic nuclear industry and the role the EPA will play in the sector.
Catsimatidis kicked off the interview by asking if the U.S. will be able to reach total energy independence. Zeldin responded by saying that decreasing energy dependence on other countries, especially adversaries, was a top priority for him and the Trump administration.
Yigal Ronen
Nuclear Science and Engineering | Volume 52 | Number 1 | September 1973 | Pages 147-150
Technical Note | doi.org/10.13182/NSE73-A23300
Articles are hosted by Taylor and Francis Online.
The functional analysis technique is applied for estimating upper bounds of changes in eigenvalues of integral equations. In particular, the method is used to determine the value of the time decay constant resulting from perturbations in a steady-state system. The method has no restrictive limitations as to the type of operator. The applications of this method are illustrated by examples from reactor theory. The effect of changes in cross sections of a fast system on the decay constant is studied.
