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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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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.
M. M. R. Williams
Nuclear Science and Engineering | Volume 136 | Number 1 | September 2000 | Pages 34-58
Technical Paper | doi.org/10.13182/NSE00-A2146
Articles are hosted by Taylor and Francis Online.
A general formulation is developed for calculating the mean neutron flux in spatially random media. It is based upon Keller's first order smoothing approximation and starts from the integral form of the transport equation in which the number densities of the various nuclear species are considered as stationary random variables. The mean flux is shown to be described by a linear integral equation. In some special cases this has been solved. In particular, for a purely absorbing medium we calculate the flux in the neighborhood of point, line and plane sources and demonstrate the importance of the degree of anisotropy in the correlation function. We also obtain an analytical expression for the collision probability in a spatially random medium and compare this with its deterministic analog.An explicit solution for the mean flux in an infinite medium is obtained in terms of a general source distribution using Fourier transforms. Using image pile theory we are able to calculate the effect of randomness on the critical size of a body. We can show that, for a fissile material, spatial randomness always increases the reactivity of the mixture.