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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.”
Ronald J. Lipinski, John E. Gronager, Michel Schwarz
Nuclear Technology | Volume 58 | Number 3 | September 1982 | Pages 369-378
Technical Paper | Fission Reactor | doi.org/10.13182/NT82-A32972
Articles are hosted by Taylor and Francis Online.
Received November 3, 1981 Accepted for Publication Feburary 24, 1982 The results of a fission-heated sodium-U02 particle bed heat removal experiment (D-4) are presented and the effects of cooling the overlying sodium below saturation are discussed. Single-phase convection began at a Rayleigh number an order of magnitude smaller than for water. Bed disturbances were observed to occur at the onset of boiling, but only after a previous boiling cycle. The disturbances are believed to be due to the flashing of superheated liquid sodium after noncondensable gases had been removed during a previous boiling cycle. The start of bed dryout was observed with two different overlying sodium temperatures (300 and 600°C). The dryout power was 0.77 kW/kg with 300°C overlying sodium (and 29 kPa pressure) and 3.58 kW/kg with 600°C sodium (and 43 kPa). It is believed that cold overlying sodium reduces the large heat-removal capability of shallow beds by causing vapor condensation within the bed and suppressing channel formation. Steady-state temperatures above the boiling temperature were observed at the bed bottom for several power levels above the incipient dryout power, indicating stable dry zones.