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The electrocatalytically active films based on nanodispersed titanium dioxide modified by Y3+ ions and synthesized by the sol-gel method were characterized by the X-ray diffraction (XRD) and ultraviolet-visible photocurrent spectra. Electrocatalytic properties of the TiO2 and Y–TiO2 electrodes were investigated during the process of oxygen electroreduction.The XRD results indicated that the TiO2 and Y–TiO2 powders with the yttrium content of 0.5–5 mol % calcined at 500°C had an anatase crystal structure, with the crystallite size of 10–12 nm. The electrodes based on the Y–TiO2 films were photosensitive in a wavelength range of 250–400 nm. For all investigated samples with the Y(III) content of ≤ 5 mol %, both an increase in the photocurrent quantum yield and a shift of spectra towards longer wavelengths vs. those of the undoped TiO2 were observed. The photocurrent quantum yield for the Y–TiO2 samples first increased and then decreased with increasing the Y(III) content, and reached its maximum with 2% Y–TiO2 films. It was found that doping of the TiO2 films by Y(III) improves the catalytic activity of the Y–TiO2 electrodes in the reaction of oxygen electroreduction. A correlation between photo- and electrocatalytic properties and structural changes occurring in the TiO2 films upon yttrium doping has been revealed.

The aim of this study was to elucidate conditions that determine properties of B X N Y C Z nanostructure powder coating. Produced in a xenon high-flux optical furnace in a flow of nitrogen coating is nonuniform, does not cover all surface and consists from equiaxed particles of sizes 10–500 nm. High-temperature gradients promote the formation of a continuously varying phase composition of coating depending on the particle size. The largest particles of coating display two types of the powder precipitates: based on carbon and based on boron nitride. Phase composition of the largest particles includes different graphite phases with a prevalence of amorphous carbon, hexagonal BN and (BN) 0,26 C 0,74 , rhombohedral B 4 C and B 10 C. Raman spectroscopy has confirmed incorporation of carbon to h-BN powder and formation structures with boron in carbon layers and carbon in BN layers, respectively. Obtained powder coating was used in an electroreduction process for measuring oxygen dissolved in a liquid.

The paper analyzes data of the long-term monitoring of Hepaticola hepatica (Bancroft, 1893) Hall, 1916 prevalence in rodents in subtaiga small-leaf forests of the Northern Baraba lowland (the Severnyi raion of Novosibirsk oblast). The study found that the prevalence was (10.4 ± 1.02)% in Arvicola terrestris L., 1758; 4.5% in Microtus agrestis L., 1761; 3.4% in M. oeconomus Pall.,1776; 1.4% in Clethrionomys glareolus Schreb., 1780; 1.0% in C. rutilus Pall., 1779; and 0.2% in Apodemus agrarius Pall., 1771. A. terrestris was shown to become dominant in rodent communities during its outbreaks and play the main role in completing the life cycle of the parasite. During low density of A. terrestris, the H. hepatica reservoir in the biocenosis is maintained by other rodent species.

Natural foci of opistorchiasis were studied in southern West Siberia. It has been shown that the foci are of two biocenotic groups: floodplain-river and lake-interfluve. The main difference between them is that in the former intermediate hosts of opistorchides are commercial Cyprinidae fish and final hosts are humans and domestic carnivores, whereas in the latter, intermediate hosts are noncommercial Cyprinidae fish, wild carnivores, and muskrat. Floodplain-river foci are associated with river basins in the north of Baraba, big and small tributaries of the Ob and Irtysh rivers, as well as euthrophic lakes within floodplains of the rivers. Lake-interfluve foci are associated with euthrophic and dystrophic lakes in the river floodplains which do not communicate with the Ob-Irtysh water system. They are located in North Kulunda and in the south of Baraba lowland.

Third-stage larvae (L3) of Soboliphyme baturini were discovered for the first time in shrews, Sorex cinereus and Sorex tundrensis from Alaska and the Nearctic. Shrews were found to be infected with L3 at Suloia Lake, south- eastern Alaska, Togiak National Wildlife Refuge, southwestern Alaska, and at the Yukon-Charley Rivers National Preserve near the Yukon-Alaska border. Larvae in shrews from Alaska were morphologically indistinguishable from those known in both insectivores and arvicoline rodents from Russia. The occurrence of S. baturini in Alaskan insectivores further establishes shrews as important hosts in the transmission of S. baturini among mustelids and other carnivores and indi- cates for the first time the basis for a paratenic cycle in the Nearctic.

Structural phase transitions of the B1–B2 type in alkali halide crystals are investigated at a temperature other than 0 K. The pressure of B1–B2 phase transition is calculated as a function of temperature. The calculated pressure of B1–B2 transition in these crystals is weakly and almost linearly dependent on temperature. For a number of ionic crystals, the p 0(T) curve has a maximum at some value of temperature.

The features of structural phase transitions that occur under high pressure are studied. The density functional theory is used to calculate the B1–B2 phase transition pressure as a function of the crystal size for small-sized alkali halide crystals. A size effect (an increase in the phase transition pressure as the crystal grain radius decreases) is revealed for the B1–B2 transitions in all halogen compounds except for lithium fluoride, for which the dependence is inverse.

The dielectric—metal structural phase transition in alkali halide metals under conditions of extremely high pressures is studied using the method of electron density functional (MDF). The values of metallization pressure are calculated for both infinite crystals and nano-size samples. The dimensional dependence of metallization pressure is revealed, namely, the dependence of the value of phase transition pressure on the initial size of crystal.

The polymorphic transformations in alkali halide crystals at temperatures above absolute zero are numerically simulated using the proposed method.

It is shown that the metallization of a dielectric in the region of its interaction with laser radiation is a substantiated mechanism of laser damage of wide-gap dielectrics. Calculations of the radiation pressure produced by high-power laser radiation and the pressure of external bulk compression at which the dielectric energy-gap width becomes zero and which is calculated on the basis of the self-consistent statistical electron theory of ionic crystals have shown that these pressures are of the same order of magnitude.

The conductivity of a macroscopically disordered graphite-paraffin system as a function of the graphite content and temperature is studied. It is shown that the properties of the heterosystem differ essentially from those of its components. Experimental data obtained are explained in terms of the percolation theory and concepts of fractal-structure objects.

High-pressure-induced structural phase transitions in alkali halide crystals have been studied. The pressure of the B1-B2 phase transition in crystals of finite dimensions is studied with the use of pair-interaction potentials within the theory of inhomogeneous electron gas. It is shown that the pressure of polymorphous transformation depends on the initial crystal dimensions. The anomalous dependence of the transition pressure on the dimensions of crystalline grains in lithium fluoride is considered and interpreted. Some structural and surface characteristics of the B1 and B2 modifications of a number of alkali halide crystals are calculated in the approximation of seven coordination spheres.

The present paper analyzes the properties of structural phase transitions under the extremal conditions of high pressures. In the context of the theory of density functional (TDF), the pressures of the B1–B2 transitions are calculated for small alkali-halide crystals as functions of the crystal size. The size effect of the B1–B2 transition – an increase in the transition pressure with the decreasing crystal grain radius – has been established for all investigated halides except lithium fluoride for which the dependence is reverse.

Structural phase transitions induced in alkali-halide crystals by an ultrahigh pressure are investigated. The pressure of the B1–B2 transition in an infinite crystal is calculated with the use of ion pair interaction potentials obtained by the self-consistent method in the context of nonuniform electron gas theory. In the approximation of seven coordination spheres, relative changes in volumes of B1 and B2 modifications of a number of alkali-halide crystals are calculated.

The paper is devoted to the study of the characteristics of structural phase transitions occurring in ionic crystals under an extremely high pressure. The calculations are made for crystals of infinite size at absolute zero temperature. The pressure ofB1-B2 polymorphic transformation is calculated for a number of alkali halide crystals using pair interaction potentials obtained self-consistently within the framework of inhomogeneous electron gas theory. In so doing, the effects of seven coordination spheres are taken into account in the thermodynamic potential. The changes of the cohesion characteristics of crystals (cohesion energy, lattice constant) are calculated for the transition from theB1 structure (NaCl type) to theB2 structure (CsCl type). Based on the obtained results, conclusions are made on the stability of one or another crystal structure in the given range of external pressure. For crystals in the B1 phase, the moduli of elasticity and relative changes of the volume at the phase transition pressure are calculated. It is shown that the inclusion of the effect of higher coordination spheres affects considerably the values of the elastic characteristics of ionic crystals.

The surface contribution to the thermodynamic potential for bulk and nanodimensional particles of ion crystals is estimated with the help of the electron statistical theory of ion crystal lattice. A number of size effects associated with the excess surface energy of ultradisperse particles are considered. In particular, the possibility of stability loss in the crystal lattice upon the transition of the surface energy to the range of negative values under a high pressure is predicted.

The cestode species Mathevolepis larbicus Karpenko, 1982 parasitizing shrews in Russian Far East is restored. As the holotype was lost, the neotype is selected. The redescription and differential diagnosis of the species are given.

The water shrew population was studied in Ust-Urgulca (Novosibirsk Province) in 1978-1990; abundance, sex and age structure, reproduction rate of this animal and its helminth fauna were examined. It was found that the abiotic factors (in particular the water level of habitat areas) influenced on the water shrew populations. The number of water shrews increased when the high water level increased. In these conditions, the population of the water shrew rejuvenated and the numbers of females increased with some increasing their fertility. In the helminthes fauna associated with the water shrew, predominated the parasite species developing in water invertebrates or ones living near water basins. When water habitats dried out, the number of water shrews decreased and individuals retained only in some areas and the population became old.

A new genus Brachylepis gen. n. hymenolepididean cestodes associated with common shrews (Sorex) in Siberia and Russian Far East is created. These genus includes three species removed from the genus Mathevolepis: Brachylepis morosovi (Karpenko, 1994) comb. n. (type species), B. sorextscherskii (Morosov, 1957) comb. n. and B. triovaria Karpenko, 1990) comb. n. The new genus is characterized by the gradual strobila with a little number of segments, unarmed scolex with apical glandular organ, by lack of internal seminal vesicle and differential seminal receptacle, by form of uterus as horse shoe in young worms and buble-like in mature worms. A tendency of inverse proportional dependence between the number of uterus segments in the strobila and the number of hexacanths in the uterus has been noticed. The table of differential characters for the species of the genus Brachylepis is proposed.

Materials reflecting opisthorchiasis infection in fish in the Novosibirsk region were analyzed. On the basis of fish population estimation and studies on its invasion with Opisthorchis felineus (Rivolta, 1884) it was shown that a considerable part in maintaining opisthorchiasis foci is played by Leucaspius delineatus. It is numerous, can easily acclimatize itself in natural water bodies, inaccessible for predatory animals, easily infected with Opisthorchis larvae, and therefore can play an important role in formation of new opisthorchiasis foci during amelioration of Kulunda and Baraba forest-steppe.