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Division Spotlight
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.
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.
G. P. Calame, F. D. Federighi
Nuclear Science and Engineering | Volume 10 | Number 2 | June 1961 | Pages 190-201
Technical Paper | doi.org/10.13182/NSE61-A25958
Articles are hosted by Taylor and Francis Online.
Knowledge of the spatially dependent thermal spectrum near an interface between different media is important for many reactor calculations. The Kantorovich variational method is utilized to solve the equation where the subscript n denotes the nth spatial region. A functional, J, of Φ(E, ) and of Φ+(E, ), is found such that the solutions to the equation and its adjoint make J stationary. Trial functions for Φ and Φ+ are employed which are linear combinations of the infinite medium spectra and adjoints, respectively, of a hard and a soft region. The constants of combination are undetermined functions of . These trial functions are inserted into J and the energy integrations performed. When the resulting expression is made stationary with respect to arbitrary variations of the adjoint constants of combination, there results in the nth region a set of two coupled differential equations for the flux constants of combination. The equations are solved simultaneously, yielding the energy spectrum as a function of position. The spectrum is used to obtain activation rates, and the rates are compared to experiments. The agreement is excellent. The method, that of overlapping groups, appears to be a promising one for the solution of the thermal space energy problem in more complex reactor calculations.