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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
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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August 2024
Latest News
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.
W. M. Lopez, J. R. Beyster
Nuclear Science and Engineering | Volume 12 | Number 2 | February 1962 | Pages 190-202
Technical Paper | doi.org/10.13182/NSE62-A26058
Articles are hosted by Taylor and Francis Online.
Neutron diffusion parameters in water have been measured at 26.7°C with the pulsed neutron technique. The results are 210 ± 1 µsec for the neutron mean lifetime, 37,503 ± 366 cm2 sec−1 for the average diffusion coefficient, and 5116 ± 776 cm4 sec−1 for the diffusion cooling constant. From these values the thermal absorption cross section of hydrogen and the thermal diffusion length in water can be inferred to be 325 ± 2 mb and 2.83 ± 0.02 cm, respectively. With a pulsed high-intensity neutron source provided by an electron linear accelerator, neutron lifetime measurements were performed on small and large water samples with values of the geometrical buckling from 0.014 cm−2 to 0.59 cm−2. Effects of harmonic modes in the large water geometries, which were determined by measurements of the time-dependent spatial flux distributions resulting from an external pulsed source of fast neutrons, were found to be adequately predictable with simple diffusion theory.