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The relation between the accuracy of measurements of the radiochemical purity of a radiopharmaceutical sample by scanning the bands of a thin-layer chromatograph and the scanning parameters is demonstrated. The components of the measurement error are determined. The results of work to produce a metrological and apparatus backup for this method, in the form of the Gammaskan-01A scanning instrument, are presented.

A method is devised for the fabrication of composite materials in which heat-generating mixtures (Fe powder, activated carbon, water, and additives) are incorporated into polymer fibers. The air oxidation of Fe in such materials is studied. The results demonstrate that the thermal and mechanical properties of the composite depend on the fabrication conditions, filler composition and content, physicochemical properties of activated carbon, and some other factors. The caloric value of the composite is 2360 J per gram of Fe.

57 Fe γ-resonance (Mossbauer) study of Bi-2212 HTSC was performed in the 30–295 K temperature range in order to investigate vibrations of the Cu-sites in the CuO 2 sub-lattice planes. Anomalous changing of their mean-square displacement has not been observed in the vicinity of temperature of a transition to superconducting state. Great attention was paid to the accuracy of measurements.

Self-calibrated resistance thermometers to be used as standards have been investigated. The heat exchange of the sensor coil with liquid helium per unit coil surface area at 0.3 K is 12 times better than that of a conventional gas-filled thermometer. The exchange is due to Kapitza surface thermal resistance. The λ point in liquid helium filling of the thermometer is reproducible to within 0.1 mK.

We describe standard resistance thermometers made of a rhodium-iron alloy designed for operation in the temperature range 0.02-2 K. The sensitive element of the thermometer is filled with liquid helium-4 or helium3, which improves the heat exchange by several orders of magnitude. This makes it possible to significantly increase the measuring current and to use conventional technology for precise measurement of resistance.