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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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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.
James W. Wade
Nuclear Science and Engineering | Volume 4 | Number 1 | July 1958 | Pages 12-24
Technical Paper | doi.org/10.13182/NSE58-A25516
Articles are hosted by Taylor and Francis Online.
The neutron age for fission neutrons and Po-Be neutrons was measured in mixtures of D2O and H2O. The age was evaluated from the second moment of the slowing-down distribution at the 1.4-ev resonance of indium. The ages of fission neutrons at concentrations of 99.8, 99.0, 98.4, 95.3, 94.0, 91.8, 48.6% D2O, and in pure H2O were 109, 107, 106, 93, 86, 78, 38.6, and 31 cm2, respectively. In the range from 100 to 90% D2O, the rate of decrease of the age was approximately 4 cm2 for each additional per cent of H2O. The ages of Po-Be neutrons in 99.4, 48.6% D2O, and in H2O were 148, 72.5, and 55.7 cm2, respectively.
