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Single-phase samples of the Sn 2-2x Sb x Fe x O 4 solid solution were prepared by solid-state reaction in air at 1300 °C for 0.26 e x e 0.66. The crystal structure of the Sn 2-2x Sb x Fe x O 4 phases was studied by electron diffraction and X-ray powder diffraction. The compounds crystallize with the rutile type structure with a disordered arrangement of cations (P4 2 /mnm space group, a ) 4.7127(6) Å, c ) 3.1595(4) Å, R I ) 0.020, R P ) 0.019 for Sn 1.48 Sb 0.26 Fe 0.26 O 4 and a ) 4.6682(8) Å, c ) 3.1147(6) Å, R I ) 0.030, R P ) 0.022 for Sn 0.68 Sb 0.66 Fe 0.66 O 4 ). The valence state of cations in the Sn 1.48 Sb 0.26 Fe 0.26 O 4 and Sn 0.68 Sb 0.66 -Fe 0.66 O 4 samples was determined by means of 119 Sn, 121 Sb, and 57 Fe Mo ¨ssbauer spectroscopy. The presence of Sn(II), Sb(III), or Fe(II) low valent state species was not detected in the samples. Resistivity vs temperature measurements revealed a semiconducting behavior from room temperature up to 900 °C with about four orders in magnitude decrease of the resistivity. Solubility tests in the cryolite-alumina melt showed that the steady-state concentration of dissolved tin for the samples with x ) 0.26, 0.36 is significantly lower than that for SnO 2 . The electrocatalytic activity and solid degradation products of Sn 2-2x Sb x Fe x O 4 are compared with those of another possible anode material (SnO 2 with small amount of the CuO and Sb 2 O 3 additives). These tests allow evaluation of the prospects of the Sn 2-2x Sb x Fe x O 4 solid solutions as inert anode materials and to formulate an approach to further improvement of their degradation stability.

The performance of SnO 2 ceramic anodes doped with copper and antimony oxides was examined in cryolite alumina melts under anodic polarization at different cryolite ratios, temperatures, times, and current densities. The corroded part consists of a narrow strong corrosion zone at the anode surface with damage of the intergrain contacts and a large increase in porosity, a wider moderate corrosion zone with a smaller porosity increase, and a Cu depletion zone, where the ceramic retains its initial microstructure and a slight porosity increase occurs due to the removal of the Cu-rich inclusions. Mechanical destruction of the anode was never observed in the 10-100 h tests. A microstructural model of the ceramic was suggested, consisting of grains with an Sb-doped SnO 2 grain core surrounded by an ϳ200 to 500 nm grain shell where SnO 2 was simultaneously doped with Sb and M n+ ͑M = Cu 2+ ,Fe 3+ ,Al 3+ ͒. The grains were separated by a few nanometers thick Cu-enriched grain boundaries. Different secondary charge carrier ͑holes͒ concentrations and electric conductivities in the grain core and grain shell result in a higher current density at the intergrain regions that leads to their profound degradation, especially in the low temperature acidic melt.

The monitoring of the physiological and functional state of personnel from dangerous industries is very important for the ensuring of ecological security. Usually, this involves testing for the consumption of alcohol and drugs of abuse. During the last several years the use of legal psychotropic drugs has increased and the control over these drugs has became an actual problem. As is well known, the long-term history of drugs present in the body is accessible through hair analysis. This is why the aim of our research is to create a screening procedure based on coupling high-performance thin-layer chromatography with microliquid extraction as a psychotropic drug testing method for hair. Some widely distributed antidepressants, neuroleptics, and sedative drugs are chosen for research. The optimal experimental conditions for all of the consequent steps for the screening detection of the model samples are determined. The visual and densitometric detection limits allow for the employment of the proposed technique for a fast and cost-effective analysis of the drugs of abuse.

Every year, the discovery and elimination of adulterated medicinal preparations becomes a more difficult and important problem. Adulterated preparations are hazardous because their can contain no active (working) components or these components can occur in the amounts insufficient for the therapeutic effect. Because of the growth the amount of adulterated products in the market, the development of rapid methods for the analytical control of pharmaceutical preparations is an important problem.Currently the medicinal remedies Naphazoline, Naproxen, Propranolol, and Terbinafine (scheme) are identified using molecular optical spectroscopy, highperformance liquid chromatography, and test methods (Table 1). Titration (for pure substances) and high-performance liquid chromatography (for combined preparations) are commonly used for the quantitative determination [1]. Similar data have been reported in some pharmacopoeia articles of Russian companies. Titration is a rather time-consuming and laborious technique, and chromatographic methods involve relatively complex preliminary sample preparation.In recent years, luminescence analytical methods found wide application for the determination of active components in medicinal preparations. The determination of the target component in the presence of fluorescing impurities by conventional fluorimetric procedures is commonly complicated by spectral overlaps, the absorption of the fluorescence of one component by the others, etc. In our opinion, a more reasonable technique consists in the determination of naphthalene derivatives and some other phosphorescing compounds on the basis of phosphorescence measurements, because the triplet states of the analyte molecules are more characteristic in comparison with the singlet states. The selectivity of the determination is substantially improved by the time selection of the fluorescence analytical signal.In some works by foreign authors [2-5], active phosphorescing components of different medicinal preparations were determined using the room-temperature phosphorescence (RTP) method. However, the ARTICLES Abstract -The use of room-temperature phosphorescence was proposed for the determination of active components containing naphthalene rings in their structures in medicinal preparations. It was demonstrated that this method can be used for the determination of active components in combined preparations.