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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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DOE issues new NEPA rule and procedures—and accelerates DOME reactor testing
Meeting a deadline set in President Trump’s May 23 executive order “Reforming Nuclear Reactor Testing at the Department of Energy,” the DOE on June 30 updated information on its National Environmental Policy Act (NEPA) rulemaking and implementation procedures and published on its website an interim final rule that rescinds existing regulations alongside new implementing procedures.
W. Häfele, L. Dresner
Nuclear Science and Engineering | Volume 7 | Number 4 | April 1960 | Pages 304-312
Technical Paper | doi.org/10.13182/NSE60-A25721
Articles are hosted by Taylor and Francis Online.
The flux distribution of a pulsed neutron experiment is expanded in terms of eigenfunctions with respect to both energy and space. The diffusion cooling constant is given exactly in terms of matrix elements with respect to these eigenfunctions. These matrix elements are evaluated for the special case of a heavy gas moderator. It is also possible to develop the theory for heterogeneous assemblies. The interaction of the cell and the assembly buckling in these structures is described and the diffusion cooling effect is considered. In addition to the normal diffusion cooling effect, a second cooling effect appears which is due to the neutrons which diffuse into the lumped absorbers.
