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We prove that any linear partial integral operator acting from the space of continuous functions to the Lebesgue class $$ {L}_p\left({D}_{\beta}^{\left({n}_2\right)}\right),1

We consider partial integral in the classes of functions with the mixed Lp– and supnorms or in the anisotropic Lebesgue spaces. For second kind Fredholm integral equations with partial integrals we construct solutions in the form of the operator Neumann series by the method of successive approximations.

The turbidity of the culture fluid (CF) and the volume of clarified CF obtained by using nine different filters with the same area (25 cm2) and their combinations were compared.

The task to provide flight safety is solved both at the stage of design and manufacture of aircraft and during its operation. Flight safety is influenced by three groups of factors: a human factor, a technical factor and marginal ambient conditions. In spite of the fact that only about 3% of aviation accidents are caused by marginal ambient conditions, in many cases there was a combination of the human factor as the main one with the availability of the accompanying unfavorable external conditions, especially marginal weather conditions. The article provides a comparative analysis of a flight safety factor in commercial civil aviation in the Russian Federation and the United States and analyzes accident statistics caused by adverse meteorological conditions. Since the greatest number of accidents related to marginal weather conditions occurred with helicopters, the article has highlighted the possibility of increasing helicopter flight safety by creating a methodology for risk assessment associated with the influence of adverse weather conditions before the flight operation. Risk assessment techniques, such as the ICAO Risk Assessment Matrix, the CFIT checklist, FRAT, have been analyzed and the feasibility of using the FRAT methodology has been demonstrated. On the basis of the FRAT methodology after updating the section "Operating conditions of the aircraft", a risk assessment methodology for the forthcoming flight of helicopters was obtained. A risk level admissibility scale for the forthcoming flight was proposed to interpret the obtained values of the risk level.

The problem of the unfavorable weather conditions impact on aircraft, including electric discharges on aircraft, continues to be relevant. For the successful implementation of flights, aviation as a type of transport should ensure safety, regularity and economy of air transportation. The aerial meteorology always takes an active part in above problems solution, since flight safety depends on timely prediction of unfavorable weather conditions. Modern airfield and aircraft equipment, as well as a new meteorological technique, helped to improve flight safety and reduce the number of accidents associated with adverse weather conditions, but this did not solve all the problems of civil aviation meteorological support. This problem is especially acute in small airports, where there are often no means of meteorological support and warnings about dangerous weather phenomena or they are insufficient. The article analyzes various unfavorable weather conditions, their influence on aircraft, provides statistics related to unfavorable weather conditions of aviation accidents, and shows the proportion of meteorological conditions among the factors affecting safety. Particular attention is paid to the problem of electric discharges to aircraft. The consequences of electric discharges on aircraft, as well as weather conditions contributing to electric discharges, are analyzed. In order to improve flight safety at local airports, it is proposed to create mobile units for collecting, processing and transmitting meteorological information that is territorially spread over the aerodrome zone; it allows to create mobile meteorological radar network. The structural scheme of the deployment of the mobile network for meteorological radars is given.

Over the past decades, the world’s steel industry has implemented two areas of its development: construction and commissioning of modern mini-plants; modernization of enterprises with a full metallurgical cycle. Despite a number of advantages of mini-plants, the global growth of steel production since 2000 has been largely due to the construction and commissioning of Converter production in China. The article presents data on the development and restructuring of metallurgical enterprises with a full cycle, primarily in the conditions of ferrous metallurgy of the CIS and former USSR. The main technological equipment for metallurgical processing, including the production of iron, steel, blanks, finished products, as well as the volume of production per year for the leading enterprises of the CIS and the former USSR was described in the article.It is also noted that in connection with the annual re-equipment of the production capacity of the main workshops in the steel industry of the former USSR, the training of highly qualified engineers and workers was the most important task of the state.

We establish the existence and uniqueness of continuous solutions to systems of linear and nonlinear integral equations with partial integrals, with partial integrals and potential type kernels, and fractional partial integrals. We obtain conditions guaranteeing that the solutions have continuous partial derivatives and are continuously differentiable.

The possibilities of matching low-frequency underwater sound pulses to the parameters of an oceanic waveguide are considered. The objective is to optimize the system of few-mode tomographic observation in a shallow-water sea. Experimental data are analyzed for two methods of selecting the low-frequency fewmode pulses propagating in a shallow-water sea. The first method excites probe pulses by vertically elongated arrays, with spatial filtering after vertical or horizontal arrays receive the pulses. The second method is based on exciting broadband signals with linear frequency modulation by a single transmitter. The selection of the few-mode signal is performed by time strobing the signals at the output of the matched filter after a horizontal array receives the pulses. The distance between the sound sources and receiving systems varied from 10 to 300 km.

Possibilities of high-frequency acoustical underwater observations of small-size objects in marine shelf zones are experimentally investigated using vertical and horizontal arrays radiating and receiving complex structure pulses in the presence of strong reverberation. Reconstruction of parameters of the observed objects yielded 35- to 40-dB weakening of the reverberation interferences due to medium-matched spatial, temporal, and Doppler filtering.

Possibilities of formation of coherent high-frequency signals for underwater acoustic observations in shallow-water shelf zones of the ocean with an irregular bottom are experimentally investigated. The methods of medium-conjugate excitation and receiving of complex modulated pulses with the help of vertical and horizontal arrays are probated. It is shown that medium-conjugate spatial, frequency, and time filtering makes it possible to decrease reverberation interferences by more than 40 dB.

Bearings produced by the Moskovskii Podshipnik Joint Stock Company (formerly the name First State Bearing Plant GPZ-1) are supplied to various enterprises in Russia, the countries of the former USSR, and other countries. GPZ-1 was built very rapidly in the first years of Soviet power and became a pioneer of the powerful domestic bearing industry (the USSR had about 30 bearing plants). Today the Moskovskii Podshipnik JSC can produce more than 2000 standard sizes of bearings of all kinds and accuracy classes with a size (race diameter) from 22 to 2050 mm and a mass from 40 g to 6.5 tons. At the present time the plant produces radial bearings that take on radial loads, radial thrust bearings that operate under the action of radial and axial loads, and thrust bearings operating under axial loads only. The bearings may be of ball or roller type, and the rollers may have various configurations, namely, cylindrical (short, extended, needle), conical, barrel-shaped, twisted. They may be single-row, double-row, or four-row. This paper describes the processing of chromium steel for bearings and the quality of the metal.

Six site-specific restriction endonucleases were isolated from Bacillus thuringiensis strains chosen of 58 strains ought purposefully for production of restriction enzymes. All six strains produce isoschisomers of Sau3A.

The quality of bearings produced by the plant and hence their competitiveness depend in many respects on the quality of the materials used in manufacturing their parts, This implies the importance of the input control of both the base and auxiliary materials.

1. Schedules for preparing ingots of alloy AMg5 affect the distribution of alloying elements in α-solid solution based on aluminum and insoluble phases; with an increase in melt temperature the content of magnesium in solid solution probably becomes greater than in excess phases; after casting at increased rates the basic amount of magnesium remains in excess phases. 2. During annealing of alloy AMg5 castings there is decomposition of solid solution whose character is affected by the original cast structure; a more supersaturated solid solution decomposes more intensely. An increase in annealing duration from 3 to 10 h provides more uniform distribution of alloying elements in the alloy. 3. The nature of solid solution decomposition during annealing has a marked effect on the corrosion resistance of alloy AMg5 ingots; a reduction in the degree of the dispersion of precipitating particles and the uniformity of their distribution leads to a reduction in resistance of this alloy to corrosion. 4. The corrosion resistance of alloy AMg5 is also reduced with an increase in cooling rate after annealing at 320°C.

1. A new reaction was discovered for the nucleophilic substitution of the acetoxy group in acylals by the trichloromethyl group under Makosza cyclopropanation conditions. 2. A general method was developed for the synthesis of 1-trichloromethyl-2-alken(or alkan)-1-ol acetates.

Aldehyde diacetates react with trichloromethane in the standard interphase catalysis conditions to form α-trichloromethylcarbinols or their acetates depending on temperature and time of the reaction.

2-(3-Phenoxyphenyl)isovaleric acid and several of its esters with insecticidal properties were synthesized.

1. A general method was developed for synthesizing substituted α-trichloromethylbenzyl alcohols from acylals of aromatic aldehydes. 2. A series of pyrethroids of a new type with an α-trichloromethyl group in the alcoholic fragment of the molecule was synthesized.

1. Single tempering at 580–600\dg is sufficient for complete decomposition of retained austenite in steel 20Kh2N4A with a carbon concentration in the case of 0.8% or less or with cooling after carburizing at 30\dg or lower. Incomplete cooling from the carburizing temperature and a carbon content of the case larger than 0.8% require double tempering with intermediate cooling to 30°. 2. To ensure the possibility of machining the parts, it is necessary that they be tempered at 650\dg to reduce the hardness before low-temperature quenching. 3. To obtain a case after high-temperature tempering that consists of pearlite with evenly distributed carbides (without cementite platelets), it is necessary that carburizing be conducted at a temperature no higher than 950\dg and that a steel with fine grains be used for this purpose. 4. The workability of carburized parts (especially after deep carburizing) depends to a considerable extent on the conditions of high-temperature tempering. 5. The quality of high-temperature tempering can be determined from the microstructure (sections of retained austenite cannot be permitted). The homogeneity of pearlite should match the special scale developed at the All-Union Scientific Design-Engineering Institute of the Bearing Industry (VNIPP).

1. To eliminate chilling at the unloading end of electric conveyor furnaces for heat treatment, it is recommended to change the design of the heaters in the third zone of the furnace and to arrange for separate voltage supply to the end heaters via a transformer. This increases the productivity of the furnaces by 10% and cuts down on rejects. 2. Using accurate calculation methods in analyzing the operation of complex units of electric furnaces is a reserve for raising their productivity.

1. After electron-beam treatment a uniform finely dispersed structure with cellular distribution of the carbide phase is formed in the fused zone. The sizes of the cells and the carbides depend upon the electron-beam fusion conditions. 2. Electron-beam fusion of the working surface of the experimental lot of R6M5 steel punches made it possible to increase their life by 2.5–3 times.