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Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
J. M. Fletcher, C. J. Hardy
Nuclear Science and Engineering | Volume 16 | Number 4 | August 1963 | Pages 421-427
Technical Paper | doi.org/10.13182/NSE63-A26554
Articles are hosted by Taylor and Francis Online.
The extraction by TBP of nitrato complexes of metals occurs mainly by the formation of nonconducting complexes in which the oxygen of the PO group is covalently bound to the metal, e.g., P==0 → M. In other TBP complexes, this O atom is bonded to hydrogen, e.g., to a hydrogen atom of water, of an undissociated acid, or of the hydronium ion. Three features in the extraction of metal nitrates at trace concentration from nitric acid concentrations >7M which await interpretation are the second increase in the distribution coefficient, DM; the decrease in the magnitude of this second increase as the fraction of inert diluent increases; and the change in the temperature coefficient of DM from negative to positive. Extraction (i) by bonding of the phosphoryl oxygen to an aquo group (of the aquonitrato metal complex), or (ii) by nitrato acids, do not explain these features. Measurements of the conductivity and viscosity of 100% TBP-HNO3-H2O phases are consistent with the existence of three steps as the ratio HNO3/TBP increases. In the first step, ions, postulated as (TBP·H2O·H)3O+ and (TBP·H)2(H2O·H)O+, are formed. In the second step, the molar conductivity decreases as the predominant species becomes TBP·HNO3. In the third step the molar conductivity and the water content increase by the formation of ions such as (TBP·H)(H2O·H)(HNO3·H)O+, in which a nitric acid molecule is bonded to the hydronium ion: the second increase in DM for certain metals is explained by there being similar bonding, through the oxygen of a nitrato group of the metal complex, in place of the HNO3 in this complex ion when HNO3/TBP is >1. The positive temperature coefficient shown by this form of extraction of metal nitrates is also shown in this region by the extraction of nitric acid, the conductivity, and the water content.
