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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.”
Benjamin M. Chase, Anthony W. LaPorta, James R. Parry
Nuclear Technology | Volume 205 | Number 10 | October 2019 | Pages 1312-1324
Technical Paper | doi.org/10.1080/00295450.2019.1585162
Articles are hosted by Taylor and Francis Online.
A core characterization process was completed as part of the Transient Reactor Test Facility (TREAT) restart project. The core characterization process is normally performed following a reconfiguration of the TREAT core. This characterization process includes performance of three temperature-limited transients. Prior to performing the transients, analysis is performed using KENO-VI to determine the high-temperature locations and the initiating reactivities for each transient. The point-kinetics code Simulating TREAT Reactor Kinetics (STREK) is used to estimate the peak power, peak temperature, and total energy deposition in the core. STREK also provides plots of pertinent parameters as functions of time to observe time-dependent behavior of the transient. After the transients are complete, the resulting data from these transients are used to develop operating limits for continued operation with the core configuration being characterized. The three transients for the characterization are performed in a progression of increasing initiating reactivity. The first transient has an initiating reactivity of 1.8%Δk/k. The second transient has an initiating reactivity of 3.0%Δk/k. The third transient has an initiating reactivity of 3.85%Δk/k. After the first two transients are performed, a two-point extrapolation of the data is used to determine a temporary estimate of the core operating limits. Once the third transient is complete, the resulting data are fit to an equation, and a three-point extrapolation of the operating limits for the core configuration is generated. This completes the characterization process and provides conservative limits for transient operation of TREAT.