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A methodical approach for the identification of a plant and characterization of integrated circuit technology based on an analysis of the features of a radiation response is proposed.

The possibility of obtaining composite materials in which the metal matrix is filled with CrSi2 needle microcrystals is considered. It is shown that it is possible in principle to obtain a regular structure of CrSi2 microcrystals in metal matrices of tin, aluminum, and their alloys. During chemical etching, a part of the matrix volume is dissolved, releasing “rods” of the semiconducting material. The thermoelectric parameters of such a system are estimated on the basis of the measured physical properties.

The structure of bumblebee communities has been studied in some ecosystems of Kunashir Island and Southern Sakhalin. The island taxocenes include five to eight bumblebee species. Bombus hypnorum is dominant in the majority of habitats. In geothermal areas near hot springs on Kunashir, the families of this species develop more rapidly than in areas without geothermal heating.

The bumblebee fauna of the North of European Russia includes 34 species. The trends in bumblebee diversity within the region are characterized. The species richness is the greatest in the middle taiga subzone and decreases from south to north, reaching its minimum in the Arctic tundra. Based on analysis of the zonal differentiation of bumblebee species, only four of them were found to be true arctic forms: Bombus (Alpinobombus) polaris, B. (Al.) balteatus, B. (Al.) hyperboreus, and B. (Pr.) lapponicus glacialis, whereas the rest belong to the temperate, boreal, and subboreal groups.

The notion of a dynamic compensatory system is discussed, characterized by the alternation of species occupying the leading position in bumblebee assemblages, while the total density of these pollinators in island ecosystems remains at similar levels. The functioning of the compensatory system is regulated by both abiotic factors (the weather and climate) and biotic factors (competition for trophic resources). The stability of the system is determined by the presence of reserve compensatory species capable of rapid population growth against the background of depressed abundance of other species under changing environmental conditions.

The concept that the mechanisms limiting immigration of new Lepidoptera species are analogous for islands with different ages and degrees of endemism of their biotas is discussed. Specific features of indi� vidual species play a key role in establishment of the fauna and population on small islands rather than com� petitive interactions between these species. It is most likely that the species stably coexisting on an island will display similar ecological characteristics and life cycles, which complies with the concepts of the neutral the� ory of biodiversity and biogeography. DOI: 10.1134/S1062359012060040

Ways of formation of the topical bumblebee complexes are considered on the basis of long-term research carried out in 2002–2009, in different regions of the Nenets Autonomous Area. The specific features of species distribution are analyzed, and the role of anthropogenic changes in the plant communities for the bumblebees is revealed. The complex of the dominant species in the forest-tundra and tundra zones of Northeast Europe is determined.

The thermoelectric properties of CrSi2 single crystals grown from a tin solution—melt are studied. A correlation is found between the unit cell parameters of the CrSi2 crystals, their thermoelectric properties, and solution—melt cooling conditions.

Using the solution-melt method combined with the Bridgman method, CrSi2 single-crystal needles and single-crystal tubes are grown at a temperature lower than their melting (crystallization) temperature. Microcrystals thus grown feature an anomalously high thermal emf. The growth of CrSi2 single-crystal tubes is an important step forward in the production of various devices based on high-temperature thermoelectric materials.

A new version of controlled synthesis of single-crystal and textured highest manganese silicide (HMS) MnSi1.71–1.75 is considered. This thermoelectric crystallizes on the surface of molten metals (Sn, Pb), which forms a floating lens. Such a configuration produces a narrow oriented zone with a sharp temperature gradient (zone melting). Simultaneously, Sn and Pb serve as solvents, as a result of which HMS partially recrystallizes in the form of microcrystallites in the bulk of HMS-Sn or HMS-Pb solution-melt.

MnSi1.71–1.75 single crystals are grown using the combination of solidification from solution-melt and the Bridgman crystal growth technique. The single crystals represent tetrahedral bipyramids and correspond to the highest manganese silicide (HMS) modification with lattice parameters a = b = 5.52(1) A and c = 65.7(8) A. The thermopower measured between the parallel faces of these single crystals is anomalously high for plain HMS (180–190 μV/K).