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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.
K. Ueki, A. Ohashi, N. Nariyama, S. Nagayama, T. Fujita, K. Hattori, Y. Anayama
Nuclear Science and Engineering | Volume 124 | Number 3 | November 1996 | Pages 455-464
Technical Paper | doi.org/10.13182/NSE124-455
Articles are hosted by Taylor and Francis Online.
Three types of experiments with a 252Cf neutron source are proposed to evaluate systematically the neutron shielding effects of a material. The type 1 experiment deals with each shielding material alone, the type 2 experiment combines a shielding material and a structural material, and the type 3 experiment constructs the optimization with the materials used in the type 2 experiment. In the stainless steel (SS) + polyethylene shielding system, because of the location of the SS slabs at the source side, the tenth layer of the polyethylene becomes approximately one-half the value as when the polyethylene is employed alone. This is the enhancement effect of the SS. In the type 3 experiment, the total thickness of the SS + polyethylene shielding system is 40 cm, and the total thicknesses of the SS and the polyethylene slabs are fixed at 25 and 15 cm thick, respectively. The minimum total dose-equivalent rate (neutron + secondary gamma rays) is observed when the polyethylene slabs are located at a 20-cm depth from the source side, with an arrangement of 20-cm-thick SS + 15-cm-thick polyethylene + 5-cm-thick and SS, and with a ratio of the maximum to the minimum dose-equivalent rate of 2.5. The shielding optimization can be constructed by combining the materials having different shielding characteristics. The experimental results of the three types of experiments are reproduced fairly well by using the continuous-energy Monte Carlo code MCNP 4A with a next-event surface crossing estimator.
