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Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
G. J. Fischer, D. A. Meneley, R. N. Hwang, E. F. Groh, C. E. Till
Nuclear Science and Engineering | Volume 25 | Number 1 | May 1966 | Pages 37-46
Technical Paper | doi.org/10.13182/NSE66-A17499
Articles are hosted by Taylor and Francis Online.
Doppler effect measurements have been made in two plutonium-fueled fast reactor assemblies at the ZPR-3 reactor. One assembly, Assembly 45A, mocked up a large plutonium-uranium monocarbide fast power breeder reactor having a 239Pu-to-238U ratio of 1:7. The second assembly, Assembly 45, had a considerably softer spectrum, produced by replacing 40% of the canned sodium of the previous assembly by graphite. Zone-loading techniques were used to achieve these mockups. Doppler measurements were made with samples containing highly enriched 239Pu, 239Pu, and 238U mixed in a ratio of 1:7, as in a large breeder reactor, and 238U in two rod diameters. Various check experiments were performed to test the validity of the measurements. The experimental results showed a strong negative Doppler response for 238U, in good agreement with theoretical estimates. The 239Pu in the mixed isotope fuel composition gave only a small positive Doppler contribution. A separate measurement for 235U in the power breeder spectrum was positive and in reasonable agreement with theory. The 239Pu results were the most interesting. Three degrees of increasing “hardness” of neutron energy spectrum incident upon the 239Pu Doppler element were generated by Assembly 45, Assembly 45A, and Assembly 45A with natural B4C surrounding the Doppler element, respectively. The experimental positive 239Pu Doppler effect reactivity change was much smaller than calculated for the softest spectrum. The agreement between theory and experiment improved significantly, however, as the neutron energy spectrum hardened.