On the outskirts of cities landfill bodies are formed, the territories of which are later used in urban planning. Over the buried landfill soils which represent construction and household garbage, methane flows are formed, which worsen the environmental conditions of the territories and negatively affect the psychosomatic health of residents. The goal was to study methane emissions from various buried landfills in Moscow. Our study on urbanized ecosystems in Moscow revealed different methane emissions in the soils. Thus, over young landfill bodies, the concentration of methane in the soils was 8 -16 ppm. This led to the release of methane into the atmosphere of the capital city. In the old landfill bodies, the concentration of methane in the soil was 1-2 ppm and did not cause methane emissions into the urban atmosphere. The analysis of the obtained data revealed the absorption of methane by soils on old landfill bodies at high and very high methane oxidation (Lobochevsky, Zyuzinskaya, Brateevskaya, Kashirskoe Highway and Ochakovka Streets). For organomineral horizons of replantozems with an increased content of organic matter and a loamy granulometric composition, increased methane formation and oxidation of autochthonous gas with undetected emission were detected.In technogenic and gray-humus horizons of urbanozems, methane formation and methane oxidation were reduced.

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The current practice of hydraulic engineering construction applies four methods for damping extra energy of excess water discharge: throwing out the stream into the tailwater; using twisting of the stream in the water passageway, in a water-well, and on a multistage drop; and energy damping in a vertical shaft. The cheapest method is energy damping by throwing the jet into the downstream reservoir. The main disadvantages limiting the use of this method include the need for appropriate topographic conditions in the tailrace basin, strong rocks in the river channel, and the possibility of water throwing at a large distance from the hydropower project, which restricts the use of this method. Extra energy damping with the use of twisting flow in the water passageway requires complex structures, providing for a rotational movement of water and forming a deep vacuum in the outlet conduit. The breaking of vacuum requires a large amount of air, which causes dynamic modes, and its removal complicates the design of energy damping structures. The most reliable way of energy damping is damping in a stilling well. But the disadvantages of water-sucking wells are low efficiency accompanied by an uneven distribution of specific discharges in the inlet section and a sharp increase in the cost at high-pressure hydroelectric installations. The use of multistage cross-fall drastically facilitates the operation of a stilling well and serves as its supplement. Energy damping in a vertical shaft is easy to use. Still, it results in trapping a large amount of air at all operating modes, which has limited its practical use in hydraulic engineering construction. However, the damping of flow energy in a vertical shaft except for possible air supply has shown high efficiency of operation in combination with a diversion water pipe with a reverse slope. A variant of such design of flow energy damping in a vacuum vertical shaft has been developed and studied as applied to conditions of the Rogun hydropower project. Model studies of the design on the scale of 1:100 showed high efficiency and reliability in all possible ranges of discharged flow rates.

Within the framework of microscopic fluctuation-dissipation theory, we obtain the stochastic equation describing the Brownian motion of an electron in the phonon field of the crystal lattice. An expression for the Green's function of the phonon field is found in general form and for the case of linear phonon-variable interaction of an electron with the phonon field with allowance for the potential screening of crystal-lattice nuclei. An expression for the phonon drag acting on a conduction electron in the lattice field is found and analyzed with allowance for the interaction. Frequency dependence of the coefficient of the phonon drag acting on a conduction electron is studied and the contribution of the electron-phonon interaction to the effective mass of a charge carrier is determined.