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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.
John M. Carpenter, Yasushi F. Taked, David F. R. Mildner
Nuclear Science and Engineering | Volume 98 | Number 4 | April 1988 | Pages 326-340
Technical Paper | doi.org/10.13182/NSE88-A23533
Articles are hosted by Taylor and Francis Online.
Grooved moderators provide greater neutron leakage currents from their channeled surfaces than flat moderators of the same volume. Operated in conjunction with pulsed sources to provide beams of slow neutrons, their pulse widths depend in a complicated way on the groove parameters, as does the leakage current. A one-speed diffusion theory treatment of the asymmetric grooved moderator is described, the eigenfunctions and eigenvalues are presented, and a simple graphical method for eigenvalue calculation is provided. The leakage from the bottoms of the grooves and from the tips of the fins are separately determined and the lowest order functions for a cold polyethylene moderator are calculated. The results for the lowest order time eigenvalue are in good agreement with a measurement obtained at the Intense Pulsed Neutron Source.