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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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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.
J. T. Mihalczo, W. T. King, E. D. Blakeman
Nuclear Science and Engineering | Volume 95 | Number 1 | January 1987 | Pages 1-13
Technical Paper | doi.org/10.13182/NSE87-A20428
Articles are hosted by Taylor and Francis Online.
Experiments performed with two coupled uranium (93.16 wt% 235U) metal cylinders (17.77-cm o.d., 5.08 cm thick) are the first application to coupled systems of the 252Cf-source-driven neutron noise analysis method for obtaining the subcritical neutron multiplication factor. These coaxial cylinders were separated axially by various thicknesses of either air or borated plaster between the flat surfaces. In all measurements, the 252Cf neutron source was located at the center of the outer flat surface of one cylinder, and the two detectors were located in three configurations: (a) both adjacent to the radial surface of the cylinder with the source, (b) both detectors adjacent to the radial surface of the cylinder without the source, and (c) one detector adjacent to the radial surface of each cylinder. A ratio of spectral densities obtained with the source and detectors adjacent to the cylinder with the source can be interpreted using point kinetics to obtain the subcritical neutron multiplication factor. However, when the source and detectors are placed on different cylinders, a coupled kinetics model is required to interpret the ratio of spectral densities. The cross-power spectral densities between detector and source positioned on different cylinders depend on the neutronic coupling and approach zero as the coupling does. By comparing the subcriticality from the measurements performed with borated plaster separating the uranium cylinders to those separated by air, it was found that the neutron multiplication factor was always increased by the insertion of borated plaster between the cylinders, regardless of their separation.
