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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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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.
R. L. French
Nuclear Science and Engineering | Volume 19 | Number 2 | June 1964 | Pages 151-157
Technical Paper | doi.org/10.13182/NSE64-A28903
Articles are hosted by Taylor and Francis Online.
A method has been developed for predicting the effect of an air/ground interface on the fast-neutron flux or dose at large distances from a point isotropic source of neutrons in air. The method yields numerical values for functions f(HS) and f(HD) that may be used to express the fast-neutron intensity as a function of source height HS, receiver height HD, and source-receiver separation distance R, in terms of the corresponding infinite air intensity I(R). Thus I(HS,HD,R) = f(HS)f(HD)I(R). The method is called the “First-Last Collision Model” because it is based on the influence of the ground upon the distribution of “first” collisions of neutrons about the source and of “last” collisions about the receiver. Generalized numerical results have been computed, and means have been developed for applying these results to specific cases* Comparisons of these results with those derived from Monte Carlo calculations, and from experiments performed at the ORNL Tower Shielding Facility and the Nevada Test Site indicate that the first-last collision model predicts the fraction of the infinite air intensity within 5 per cent in almost all cases.