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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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
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.”
R. Kladnik.
Nuclear Science and Engineering | Volume 17 | Number 2 | October 1963 | Pages 185-191
Technical Paper | doi.org/10.13182/NSE63-A28877
Articles are hosted by Taylor and Francis Online.
The stationary velocity-dependent transport equation for an infinite homogeneous source-free medium is solved by expanding the solution into a power series of the eigenvalues κ = 1/L. The integral equations, obtained by equating terms with the same κ0m, have been solved numerically on the IBM 704 computer using the iteration procedure. The monatomic gaseous model for the scattering process has been used assuming scattering cross section to be independent of the relative velocity and the absorption cross section to follow the 1/v law. A general expression for the diffusion coefficient in the absorbing medium has been obtained whereas the diffusion length L is obtained as the only positive real root of an algebraic equation whose order depends on the degree of the approximation. A comparison between the calculated and measured values of the diffusion length in poisoned water shows that water can be described roughly as a monatomic gas with A = 1.9 and ls(∞) = 0.40 cm. An empirical formula for the effective temperature of the neutron velocity distribution is evaluated.