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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.
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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. C. Hanna
Nuclear Science and Engineering | Volume 15 | Number 3 | March 1963 | Pages 325-337
Technical Paper | doi.org/10.13182/NSE63-A26444
Articles are hosted by Taylor and Francis Online.
Skyrme has given a theoretical treatment of the perturbation of the neutron flux in a diffusing medium by an absorbing foil. His theory is re-examined, with particular reference to the modification proposed by Ritchie and Eldridge, and the “edge correction” is evaluated. The accuracy of this modified Skyrme theory is tested by comparison with Dalton and Osborn’s computer calculations for monokinetic neutrons; the agreement is generally better than 1%. This theory is then extended to a Maxwellian neutron spectrum, for which computer calculations are not available, with the result
A is the activity per unit mass of a foil of thickness τ (in units of the absorption mean free path), Ao that of a zero thickness foil, , where t and R are the thickness and radius of the foil. The bars denote averages over the Maxwellian spectrum. The flux-depression parameter g is of the order of R/λtr, but its exact value depends on the velocity dependence of the transport mean free path, and on the thermalization properties of the medium. This formula is used to obtain, from the available measurements of the dependence of A on foil thickness, “experimental” values of g. For both graphite and hydrogenous media they are smaller than expected.