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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
Mihály Makai
Nuclear Science and Engineering | Volume 86 | Number 3 | March 1984 | Pages 319-326
Technical Note | doi.org/10.13182/NSE84-A17561
Articles are hosted by Taylor and Francis Online.
In order to shorten the time of reactor core calculations, the actual core structure is often replaced by a simpler structure, such as a periodic lattice whose neutron flux is determined through some periodic microfluxes and through an overall macroflux. In the framework of the well-known perturbation formalism, it is shown that the macroflux is obtained from a two-group diffusion equation in which the coefficients are determined from transport cross sections and microfluxes. The relationships between microfluxes are given. It is shown that in a finite core the flux is described by an asymptotic and a transient term. A simple problem is solved by means of the presented theory, showing that it is capable of providing a truncated series expansion of the exact results. The theory presented is applied to the evaluation of measurements.