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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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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April 2025
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.
H. L. McMurry, G. A. Cazier, R. W. Goin
Nuclear Science and Engineering | Volume 6 | Number 1 | July 1959 | Pages 44-48
Technical Paper | doi.org/10.13182/NSE59-A25625
Articles are hosted by Taylor and Francis Online.
For economical operation of the MTR, mixtures of new and used fuel must be distributed so that the required cycle time is met. An equation is derived which expresses the megawatt days possible from a new fuel charge in terms of the known life of the preceding charge, and the change in the initial fuel loading. The equation takes account of effects arising from differences in the initial U235 contents of the fuel assemblies, changes in the equilibrium concentrations of Xe135 and Sm149 during the run, and production of low cross section fission poisons. For certain conditions of common occurrence it reduces to a semi-empirical equation which has been used in the past for calculating fuel loadings. The theory can be used to derive equations for the charge life when fuels other than U235 are used.
