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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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Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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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A series of firsts delivers new Plant Vogtle units
Southern Nuclear was first when no one wanted to be.
The nuclear subsidiary of the century-old utility Southern Company, based in Atlanta, Ga., joined a pack of nuclear companies in the early 2000s—during what was then dubbed a “nuclear renaissance”—bullish on plans for new large nuclear facilities and adding thousands of new carbon-free megawatts to the grid.
In 2008, Southern Nuclear applied for a combined construction and operating license (COL), positioning the company to receive the first such license from the U.S. Nuclear Regulatory Commission in 2012. Also in 2008, Southern became the first U.S. company to sign an engineering, procurement, and construction contract for a Generation III+ reactor. Southern chose Westinghouse’s AP1000 pressurized water reactor, which was certified by the NRC in December 2011.
Fast forward a dozen years—which saw dozens of setbacks and hundreds of successes—and Southern Nuclear and its stakeholders celebrated the completion of Vogtle Units 3 and 4: the first new commercial nuclear power construction project completed in the U.S. in more than 30 years.
J. T. Thomas, J. K. Fox, Dixon Callihan
Nuclear Science and Engineering | Volume 1 | Number 1 | March 1956 | Pages 20-32
Technical Paper | doi.org/10.13182/NSE56-A17655
Articles are hosted by Taylor and Francis Online.
Nuclear properties of U233 and U235 are compared using data obtained in a series of critical experiments. Aqueous solutions of uranyl oxyfluoride containing uranium enriched to about 90% in each of the two isotopes have been made critical in water-reflected spherical reactors having diameters of 26.4 and 32.0 cm. Assuming the reported nuclear constants for U235 are reliably known and assuming equality of the neutron leakage spectra of U233 and U235 for the same water-reflected critical sphere, the value of η(U233) at 0.026 ev was determined to be 2.31 ± 0.03. The critical masses for the two isotopes in these systems have been measured over the temperature range from 20°C to 100°C; corresponding values of the reactivity temperature coefficient are reported. Delayed neutron yields for the two isotopes were compared by noting the periods resulting from the withdrawal of a boron poison from the critical spheres. It is shown that the yield from U233 is about one-third that from U235, in agreement with other determinations.
