Magnetically separable FeO-SiO/Pt catalysts with ~ 2% Pt loading have been developed for the generation of U(IV) in HNO-NH medium, used in the nuclear spent fuel reprocessing. Pt was impregnated in the catalysts via reductive heat treatment. The catalysts were characterized by x-ray diffraction, magnetization measurement, field emission scanning electron microscope and high-resolution transmission electron microscope studies.
View Article and Find Full Text PDFA REDOX-based analytical method was developed for determining the plutonium concentration. In this method, plutonium was oxidized to the +6-oxidation state using of ceric ammonium nitrate solution. The interference from ceric(IV) nitrate was suppressed by reducing its oxidation state from +4 to +3 with sodium nitrite.
View Article and Find Full Text PDFExperimental determination of solidus and liquidus in reactive systems at very high-temperatures requires special equipment and is rather complex. In the present study, we describe setting up an experimental facility based on the "spot-technique." It was demonstrated that this setup could be used to measure phase transformation temperatures involving liquids in refractory systems that comprise reactive and radioactive components, in the range of 1273 K-2273 K, by using a thermo-optometric technique, namely, the "spot-technique.
View Article and Find Full Text PDFRev Sci Instrum
December 2014
A semi-adiabatic isoperibol solution calorimeter has been indigenously developed. The measurement system comprises modules for sensitive temperature measurement probe, signal processing, data collection, and joule calibration. The sensitivity of the temperature measurement module was enhanced by using a sensitive thermistor coupled with a lock-in amplifier based signal processor.
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