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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Michael R. Prisco, Robert E. Henry, Michael N. Hutcherson, John L. Linehan
Nuclear Science and Engineering | Volume 63 | Number 4 | August 1977 | Pages 365-375
Technical Paper | doi.org/10.13182/NSE77-A27054
Articles are hosted by Taylor and Francis Online.
Two-phase, critical flow data are reported for initially saturated and subcooled liquid Freon-11 flowing through sharp-edged entrance tubes for length-to-diameter (L/D) ratios from 2.82 to 100. Comparisons among various analytical models and these data show that nonequilibrium models describe the critical flow phenomenon more accurately than equilibrium models. It is shown that to obtain reliable exit plane pressure measurements, it is necessary to have a gradual divergence at the exit of the constant-area tube. This minimizes the expansion of the exiting fluid, which would otherwise result in an exit pressure measurement much lower than the one-dimensional value governing the flow. Utilizing data from this study, quantitative estimates of the individual phase velocities at the condition of critical flow indicate that “vapor choking” is not the mechanism by which two-phase critical flow occurs in this investigation. The flow pattern in a transparent test section, with an L/D ratio of 2.82, has been observed and photographed, and this shows that the separated flow condition (liquid jet surrounded by vapor) begins to break up into a dispersed two-phase mixture approximately one equivalent diameter downstream of the entrance.