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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
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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.
Mark Nelkin
Nuclear Science and Engineering | Volume 7 | Number 3 | March 1960 | Pages 210-216
Technical Paper | doi.org/10.13182/NSE60-A25704
Articles are hosted by Taylor and Francis Online.
An improved theoretical basis is presented for the interpretation of the pulsed-neutron technique for measuring thermal-neutron absorption cross sections and transport parameters. A procedure is given for the exact solution of the Fourier-transformed, multivelocity transport equation in an infinite medium. The objective is the calculation of the decay constant of the thermalized neutron flux following an initial pulse of fast neutrons. The method used is an expansion of the decay constant and neutron spectrum in a power series in the Fourier-transform variable. The procedure is first illustrated for the case of isotropic scattering and then generalized to anistropic scattering by using the spherical harmonics expansion. The results are given in terms of integral equations whose solution involves a knowledge of the energy-transfer cross sections between thermal neutrons and the moderating material. The approach employed is to extract the maximum amount of information which is independent of these cross sections and to derive explicitly the equations involving them. It is necessary to solve these equations in order to obtain more accurate information. Finally, the relation of the infinite medium Fourier transform variable to the geometric buckling of a finite sample is discussed. It is noted that the conventional interpretation of the experiments in terms of the diffusion coefficient and diffusion cooling coefficient requires the assignment of an equivalent infinite medium buckling to each finite sample measured. The discussion in the present paper makes plausible the validity of this procedure.