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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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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.
R. M. Pearce, D. H. Walker
Nuclear Science and Engineering | Volume 2 | Number 1 | February 1957 | Pages 24-32
doi.org/10.13182/NSE57-A15569
Articles are hosted by Taylor and Francis Online.
The uranium metal temperature coefficient of reactivity has been measured in ZEEP. A uranium sample was oscillated in the reactor and the resulting modulation of reactor power was measured as a function of the sample temperature. The temperature coefficient of uniformly heated uranium rods, 3.25 cm. in diameter, immersed in a constant temperature moderator (moderator-to-uranium volume ratio 22) is deduced from this experiment. Over the range +30°C to +230°C the coefficient is dk/dT = − (1.25 ± O.09) × 10−5 per °C. Over the range +10°C to −140°C the coefficient is dk/df = −(1.58 ± 0.18) × 10−5 per °C.