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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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Nuclear Science and Engineering
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Latest News
Penn State and Westinghouse make eVinci microreactor plan official
Penn State and Westinghouse Electric Company are working together to site a new research reactor on Penn State’s University Park, Pa., campus: Westinghouse’s eVinci, a HALEU TRISO-fueled sodium heat-pipe reactor. Penn State has announced that it submitted a letter of intent to host and operate an eVinci reactor to the Nuclear Regulatory Commission on February 28 and plans to engage with the NRC on specific siting decisions. Penn State already boasts the Breazeale reactor, which began operating in 1955 as the first licensed research reactor at a university in the United States. At 70, the Breazeale reactor is still in operation.
C. W. Maynard
Nuclear Science and Engineering | Volume 6 | Number 3 | September 1959 | Pages 174-186
Technical Paper | doi.org/10.13182/NSE59-A25657
Articles are hosted by Taylor and Francis Online.
“Blackness theory” is described as a class of procedures for matching a high order transport approximation in one region to a low order approximation in a second region. The matching conditions are presented as a generalization of the Marshak boundary conditions. The blackness coefficients necessary in setting up the conditions are defined and tables are given for slab geometry. A method which allows all regions to be treated by means of the blackness coefficients is developed and applied to two region cells. Numerical results are compared with other approximations in situations typical of those encountered in resonance capture and thermal utilization calculations.
