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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 digital coincidence method is described in which the amplitude is digitized and the time of each pulse from the ionizing radiation detectors is recorded. The features of the processing of the digital amplitude-time measurement data are described in detail. It is shown that the digital coincidence method has a time resolution defined solely by the resolving power of the detectors.

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.

The Fe-containing products of the reaction in an Fe + C + NaCl + H2O mixture were identified by Mossbauer spectroscopy at different stages of oxidation interrupted by storage in an inert atmosphere. The results indicate that the storage of the mixture away from atmospheric oxygen leads to partial reduction of iron oxides. According to thermal analysis data, the energy stored in the heat-generating mixture studied can be used intermittently: heat release rapidly ceases after the mixture is isolated from air and resumes upon further oxidation. The reduction of iron(III) oxides during storage in an inert atmosphere stabilizes the heat-generation parameters at a nearly constant level during multiple oxidation–storage cycles.

A detailed discussion is presented on the main points of the Convention on the mutual recognition of national standards, calibration certificates, and measurements presented by national metrological institutes, and a survey is given of international collaboration to carry this out. Regional metrological organizations are important, and a survey is presented on work done in COOMET. Brief descriptions are given of ways in which the Convention may develop in the near future. The positive points from the implementation of the Convention are formulated from the author's experience and from research by other experts.

Using thermodynamic analysis of the Fe–C–NaCl–H2O–O2 system and experimental studies (x-ray diffraction and Mossbauer spectroscopy) of exothermic mixtures containing Fe metal, activated carbon, water, and NaCl, we identified the state of Fe and determined the phase composition of the reaction products at different stages of oxidation with atmospheric oxygen. The calculation and experimental results are in reasonable agreement. Under the conditions of restricted access for air, the main oxidation product is magnetite, Fe3O4 . Free access for air leads to the formation of hydrous ferric oxide, Fe2O3 · nH2O. The most stable phase under the conditions of interest is goethite, Fe2O3 · H2O (α-FeOOH). Storage of incompletely oxidized samples away from air for 7–14 days leads to partial reduction of iron(III) oxide phases to Fe3O4 and α-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.

In agreement with a prediction of the theory, we have observed experimentally the intrinsic quadrupole electric field of a centrosymmetric crystal.

In 2003, the transition period came to an end for the mutual recognition of national standards, calibration certificates, and measurements issued by national metrological institutions. The paper considers the results from international collaboration attained in that period, which were discussed at the 11th meeting of the Joint Committee of Regional Metrological Organizations and the International Bureau of Weights and Measures.

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.