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Observations of the change of the species composition and distribution of lichens in fellings, burns and in derivative forests in the East Sayan piedmonts have been made. Morphological changes of lichens under the influence of environmental changes are described.

The resistance of terrestrial ecosystems of the Baikal Region to acid precipitations has been studied, maps of distribution of the current acidity load and of critical loads of acidity on ecosystems of West Buruyatia (the Tunkin Hollow and its mountainous surroundings) and of the South-West Baikal (the Primorsky Range) have been drawn up.  It is established that the values of the current load of acidity are maximal in upper altitude zones of mountainous systems remote from industrial and agricultural centers. On the whole, the picture of spatial distribution of the critical load values follows the general laws of formation of the soil cover under the conditions of vertical zonality, becoming complicated due to spatial variability of intra-soil weathering values and of the biological circulation capacity.

The problem of estimating the level of technogenous load in industrial centers  on adjacent landscapes across snow cover contamination aureoles deciphered by spacecraft photographs is analyzed. For the industrial zone of Krasnoyarsk City, a correlation between the snoe cover contamination zones distinguished by means of NOAA/AVHRR photographs on the one hand, and the terrestrial data on the heavy meetal content of the snow cover and technogenous dust, on the other hand, has been found. The distinguished contamination zones correlate with the level of cancer diseases.

Results of analysis of snow samples collected in various districts of Barnaul City immediately after snowfall are presented.  In the samples collected, the solid phase content, and after thawing, concentration of sulphates and nitrates, as well as pH, in the liquid phase, were measured.

In monitoring studies (1992-1997), an estimation of CO₂ emission from arable soils in fallows an winter wheat sowings has been carried out. Its dependence on hydrothermal conditions, and a correlation with humus content and the magnitude of gaseous carbon losses have been demonstrated. The causes of the increase of CO₂ emission from the soils under the conditions of technogenous pollution are discussed. It is found that the cointribution of direct local technogenous CO₂ discharges into the atmosphere is not considerable as compared to the indirect influence of pollution on the increase of CO₂ from soils in agroecosystems

The dynamics of pine (Pinus sylvestris L.) stands polluted by fluorine-containing emissions was being studied for some decades - from the moment when emissions appeared till at present. Condition of the pine stands was estimated by contents of the pollutants in the needle, and a number of physiological and morphometrical parameters of the trees. Some stages in the forest decline under fluorine-containing emissions were revealed. On the base of the data obtained and the regressive analysis, situations were forecasted according to the following scenarios: a) emission load will not be changed, b) emission load will be increased, c) emission load will be decreased, d) emission load will be eliminated.

A structural analysis of energy consumption over the branches of industry and separate types of consumers is presented. It is demonstrated, on the basis of the development of the power-manufacturing capacities of Russia and global trends in the development of power electronics, that the introduction of energy-saving technologies involving the means of power electronics allows achieving substantial saving of electric power and reducing its deficit. Taking account of the structure of consumers over the branches of industry and specific features of the necessary means of power electronics, the limiting volume of the Russian market is estimated from the financial viewpoint, both with respect to the power electronic units and systems, and with respect to semiconductor devices used in them.

In the present communication we consider the major requirements to the properties of low-doped working layers of multiplayer structures used in manufacturing power high-voltage transistors, thyristors and IGBT devices, which are the most widespread types of high-power high-voltage discrete devices. It is demonstrated experimentally how the non-uniformity of thickness and resistivity of the low-doped working layer can affect the parameters of high-power MDS transistors. We analyse the reasonability of using two- and three-layered structures formed by direct bonding, involving neutron-doped silicon grown by floating zone melting (FZ-Si) for the working low-doped layer, in manufacturing power electronic devices with U_break > 800 V. It is demonstrated that an alternative for FZ-Si can be silicon, grown according to Czochralski technique under an applied magnetic field (CZM), with oxygen content < (4-5)*10¹⁷ cm^-3.

The hardness of bulk single crystal 6H-SiC, GaN and AlN was measured by the Vickers indentation method under an applied load of 0.5-5 N in the temperature range 20-1400

Silicon carbonitride films were synthesized by means of the chemical vapour deposition (CVD) process in the scheme with remote plasma. Initial compounds were the silyl derivatives of 1,1-dimethyl hydrazine: dimethyl(2,2-dimethylhydrazino)-silane and dimethyl-bis-(2,2-dimethylhydrazino)silane. The molecules of the monomers contain the bonds Si-N, Si-C and C-N which are necessary for the formation of silicon carbonitride.