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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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.
T. Wakabayashi, Y. Hachiya
Nuclear Science and Engineering | Volume 63 | Number 3 | July 1977 | Pages 292-305
Technical Paper | doi.org/10.13182/NSE77-A27041
Articles are hosted by Taylor and Francis Online.
The thermal-neutron behavior in a highly heterogeneous cluster-type plutonium fuel lattice has been studied through the measurements of the dysprosium reaction-rate distribution in a unit cell covering three plutonium fuel elements, four coolant voids, and two lattice pitches. The study included comparison with the results obtained with UO2 fuel. A new technique for locating the foils has been developed, resulting in an accurate measurement of the thermal-neutron flux distribution. Depression of the thermal-neutron flux in the fuel region is larger in the plutonium fuel lattice than in the uranium lattice because thermal-neutron absorption in the plutonium fuel is enhanced by the resonances of 239Pu and 241Pu at 0.3 eV. In addition, the 1/v cross section of plutonium is larger than that of uranium. This property of the plutonium fuel appears markedly at 100% void fraction, but less at 0% because this property is weakened by the presence of H2O coolant. The results of calculations obtained by means of the LAMP-DCA code showed good agreement with experimentally determined data within 5%.
