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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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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.”
Tsuyoshi Misawa, Seiji Shiroya, Keiji Kanda
Nuclear Technology | Volume 116 | Number 1 | October 1996 | Pages 9-18
Technical Paper | Fission Reactor | doi.org/10.13182/NT96-A35308
Articles are hosted by Taylor and Francis Online.
Experiments on the reactivity worth of beryllium metal were performed using the Kyoto University Critical Assembly, and they were analyzed to examine the validity of the computational method to treat (n,2n) reactions in calculations. The experimental results demonstrated that beryllium metal has positive reactivity worth compared with graphite. In the analysis, (n,2n) reactions were treated as modifying scattering cross sections in a transport calculation, whereas both scattering and absorption cross sections should be modified in a diffusion calculation. The results of calculations for the reactivity worth of beryllium agreed with experimental data within a few percent in the calculated-to-experimental ratio. Calculated results indicated that (n,2n) reactions of beryllium contribute by ∼85% to the positive reactivity worth compared with graphite in these experiments at a thermal reactor. Moreover, through the improved neutron and gamma-ray coupled calculation, the effect of (γ,n) reactions of beryllium on reactivity was estimated. It was found that (γ,n) reactions of beryllium can be negligible so far as this reactivity worth is concerned.