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The article investigates the modes of gas flow through the flue of a steam direct-flow generator unit using a laboratory stand formed from a cylindrical coil. The criterion for determining the gas flow regime is a dimensionless quantity called the Reynolds number. The speeds and temperatures of the airflow were determined experimentally. Based on these results, the Reynolds number was calculated and the flow modes at each measurement point were determined, as well as the dependence of the Reynolds number on temperature and velocity was obtained, the experiment was analyzed. The reason for further study of aerodynamic processes in a ramjet steam generator is substantiated.

This article provides information on the results of scientific research aimed at maintaining and increasing soil fertility in the country and in the world today, as well as ways to increase it, as well as the impact of organic fertilizers on soil fertility. The article presents evidence-based data on the study of the effect of soybean, mung bean and oat sowing in different ways with deep, medium and shallow tillage after harvesting winter wheat in conditions prone to wind erosion with low fertility, on the mechanical composition of light irrigated meadow saz, slightly saline soils for the number of bacteria accumulating nitrogen in the roots of legumes and root crop residues macroaggregates in the soil between the options increased by 0.1-10%, soil porosity by 0.6-1.5, humus content by 0.001-0.004%, total nitrogen by 0.005%, the content of nitrate nitrogen by 0.1-3.6 mg/kg. In the variants with row crops of soybean and mung bean after tillage to a depth of 30 cm after winter wheat, the yield of mung bean grain was 16.5 c/ha, and soybean 18.8 c/ha, where the mung bean yield was higher by 2.1 c/ha, and soybeans by 2.5 c/ha compared with chisel treatment to an average depth of 22-24 cm. tillage to a depth of 14-16 cm using a cultivator. With ordinary sowing, mung bean achieved a profitability of 48.1%, and soybeans 52.7%. When growing cotton next year against the background of row sowing of repeated crops of mung bean and soybeans with a plow to a depth of 30 cm after harvesting winter wheat, the yield from cotton sown after mung bean was 33.4 centners / ha, and after soybeans 34.2 centners / ha and the level of profitability increased by 39.5%.

Cotton fabric coated with polyacrylic rubber can be used as a replacement for polyethylene bags to avoid plastic pollution. In this research, we have investigated the use of polyacrylic rubber with 100% cotton fabric as a finishing agent where 2% of ammonium chloride was used as a catalyst. A pad-dry-cure technique was applied for the preparation of cotton fabric samples varying 6%, 8%, 10%, 12%, and 14% polyacrylic rubber. Tensile strength, tear strength, and bursting strength produced a balanced improvement in properties. After appealing gyro wash on each sample, it is established that the strength of the fabric has decreased slightly. Assessment of these properties has had a good impact on the strength of the fabric making which is a viable substitute for polyethylene bags.

It is known that the soils of the Bukhara oasis were formed in a dry and sharply continental climate. Therefore, the relationship between soil-forming parent rocks and groundwater is important. This article describes the natural processes that take place in this relationship, the negative effects that affect soil fertility. The article examines the mechanical composition, salinity, nutrient content, and fertility of these soils by the example of a single type of soil in Vabkent district, and describes their importance for irrigated lands. In particular, the origin, distribution, chemical properties, productivity, as well as quality of irrigated meadow-swamp soils were determined by morphological, profile and other methods compared with the results of previous years.

In the world, much attention is paid to the development and application of machine straw choppers. The aim of the study is to justify the parameters of a straw chopper in the form of a hyperboloid of polycaninic form. The basic principles and methods of classical mechanics, mathematical analysis and statistics were used in this study. The authors proposed and developed a straw chopper of polycanonical form. On the basis of theoretical studies analytical dependences for definition of the frontal area of a polycanonical straw shredder depending on its parameters are determined. Multifactorial experiments were carried out, on the basis of which the optimal parameters and mode of operation of the shredder were established: length of the working part 861 mm, angle of the tray installation 38° and rotor rotation frequency 727 rpm.

State program of developing agriculture of Uzbekistan is directed to the developmend of important field - animal husbandry and its suppiy with roug-hage, in the framework of creating small cattle-breeding, farming and peasantry, that demand a special attention at prearing high guality roughage at small material expenses. The practice showed that unsatisfactory processing of rousgh fodder stalka by fodder preparation machinery bring to quality dectine of got fodder and accordingly to the inerease of its loss (to 30 %). The authors proposed and developed a rotary straw chopper with cone-shaped working bodies. The diameter of a working body and an angle of a blade of a knife are theoretically investigated. To substantiate the type and parameters of the chopper blade, a stand for laboratory research was developed and manufactured. Change of cutting force and cutting power consumption depending on circumferential cutting speed, straw diameter, knife length and blade inclination angle were studied by experimental researches. On the basis of experimental studies the type and optimum parameters of rotor and knife were established: knife type - disc; rotor diameter 172 mm; number of knives 4; knife inclination angle 20°.

This article discusses some theoretical issues and structural capabilities of the tray cleaner working body. The process of cutting the deposited layer with an active working body. On the significant influences of the translational working speed on the cutting process of the alluvial soil layer, as well as on the effects of the speed parameter of the working body on its energy intensity.

Research work has been carried out for several years in order to mechanize the technological process of dams' compaction and the development of a dam compactor. As a result of the experiments, the design of the dam compactor and the types of operating bodies were selected, the main optimal dimensions of the dam compactor were determined and mathematically analyzed. It was revealed that the main parameters of the dam compactor affecting the compaction process of temporary irrigating canal dams are cone roller diameter, length and width of the plate compactor, and the angle of dam nip. These parameters have been substantiated by theoretical and experimental studies. The optimal values of these parameters were determined by the mathematical planning of the experiment; below are the limits, as well as the variation levels of these factors. Based on the results obtained, an improved dam compactor was manufactured, and experimental studies were conducted in the field. At the same time, an increase in productivity relative to existing methods has been achieved and the compaction index has been brought to the required value. The mathematical model of the research object is the response function of an equation linking optimization parameters with controlled factors. The hypothesis of variance uniformity in the same non-repeated experiments was tested using the Cochran's test, and the significance of the regression coefficients was determined by the Student's criterion. The adequacy of the process model was checked by the Fisher criterion. After processing the experimental data and evaluating the coefficients' significance, regression equations describing the dam compaction process by the dam height and the compaction degree of the temporary irrigating canal dam were obtained. The main dimensions of compacting operating bodies of the dam compactor were selected.

Wood pulp industry generates tons of lignosulfonate by-product waste every year. Rational utilization of lignosulfonates is limited due to non-uniform structure and complex chemical composition. However, presence of different functional groups allows for a broad range of industrial applications, including catalysis in polymer chemistry. Therefore, the aim of this study was to analyze structural composition of sodium lignosulfonate and its modified forms using Fourier transform infrared spectroscopy (FTIR). Sulfuric acid treatment of sodium lignosulfonate was hypothesized to enhance catalytic capacity of the original lignosulfonate by increasing the amount of sulfonic acid catalytic active sites inside the structure of the macromolecule. FTIR analysis identified structural features of the lignosulfonate-based catalysts and their catalytic potential was assessed via alcohol dehydration reaction. As a result, polymeric forms of lignosulfonate were successfully used as a carbon-based catalyst matrix.

Based on studies on the interaction and heat resistance of some heat-resistant polymer additives at 128 °C, a sulfonated polyacrylamide polymer AN-125 is proposed as an additive for improving the viscosity of a surfactant composition. The results of experimental studies of a new surfactant composite prepared based on a mixture of ethoxylated and propoxylated sulfate, α-olefin sulfonate and alkylphenol ethoxylate with a concentration of 500 ppm and additives to improve the viscosity in the reservoir model from the deposit basement samples showed that the surface tension at the oil-solution boundary before the exposure to temperature is 0.19 mN/m, and after exposure to temperature 91 °C – 0.21 mN/m. The experimental studies of water and surfactant compositions injection on 5 prefabricated models composed of core samples of basement rocks covering a wide range of reservoir properties showed that the injection of the oil rim with compositions based on the mixture of ethoxylated and propoxylated sulfate, α-olefin sulfonate and alkylphenol ethoxylate with a concentration of 800 ppm and an additive of polymerasulfonated polyacylate increases the oil displacement ratio.

Commonly known, diagnostic results show that all pipelines contain a large number of defects that are unacceptable in terms of standards and building codes. An attempt to eliminate all defects can lead to the fact that the costs of further operation will become prohibitively large and not economically justified. In practice, the only way to ensure safety is to exclude only those defects that really pose a danger to the pipeline, taking into account the operating conditions. This is how the problem of assessing the residual resource of objects that have been in operation for a long time appears. Authors do not always use the same meaning in the term “residual resource”. To avoid confusion in terms, the article provides some considerations defining this term and accepts an interpretation in which it is a value derived from the strength and safety of the pipeline. A number of factors are given, which in a key way affect the strength and safety, which should be involved in the assessment of the residual resource. As a result, this approach, in contrast to the previously available ones, allows taking into account all the main factors affecting the strength, durability and safety of the pipeline.

The article is devoted to a current problem of the need to increase the explosive safety of tanks. The paper analyzes the causes of explosions in tanks. Constructive solutions of existing stationary tank roofs are analyzed, including with an easily removable sheathing. The required areas of loss of containment of the tank roof are calculated depending on the type of flammable liquid. The dependence of the level of filling the oil product in the tank on the excess pressure during the explosion has been determined. Criteria and requirements have been developed for fixed roofs with easily removable sheathing.

This paper presents results of a comparative analysis of several research methods for oil pipelines waxing process, which are based on the progress made with present-day laboratory equipment and the capabilities of software and hardware computational packages used to simulate properties of multiphase fluids and kinetics of complex multi-factor processes. This paper considers theoretical foundations of proven and substantiated mechanisms of the processes of wax formation and accumulation on the inner surface of oil pipeline walls, including main factors that impact the rate of such processes. The paper also points out disadvantages of the methods of static measurement based only on the diffusion factor of deposition of deposits, predominantly of the paraffin wax type; these static measurement methods preventing from taking into account the impact of other equally significant factors that accelerate and decelerate accumulation of deposits. This work highlights the most accurate methods to determine the chilling point or mass crystallization of paraffin waxes, which are recommended to be used in computerized simulation of the process.

Certain physicochemical properties of the synthesized graft copolymers of raw skin collagen and natural silk fibroin with polyacrylic acid have been determined. The dependence of the solubility, density, and thermal properties of copolymers on the ratio of components and synthesis conditions has been established.

The article discusses the possibility of increasing the efficiency of seed drying using energy storage. The recommended modes of the drying process and the selection of the most effective modes to use in drying units are presented. A method of additional thermal radiation for a vacuum chamber using a phase change of the heat carrier is presented. The diagram of the energy storage process and the diagram of the process of using the stored energy are shown.

In order to take into account the territorial differences of natural and economic conditions, to identify biological and ecological patterns, the agro-landscape and ecological zoning of natural forage lands (NFL) of the North-Western natural and economic region of the Russian Federation has been developed. The Karelian province occupies 23% of the area in the north of the Leningrad region, bordering Karelia and Finland. The Karelian province is located in the western part of the Middle Taiga zone, which is characterized by Eastern European Middle Taiga plains. Most of the area of the province (65%) is covered by forests. Agricultural land occupies only 4% of the total area of the province. Including arable land – 2%, hayfields and pastures – 1% each. The territory of the province is significantly moistened and swampy. Swamps occupy 11% of the area, under water – about 11%. Shrubs occupy 3% of the area of the province, other land – about 6%. The structure of NFL is dominated (53%) by normally moistened dry-grass grasslands on sod-podzolic soils. Fine-grained sweet-scented and finegrained grasslands with a large participation of various grasses are common. The yield of hay is 9–13 c/ha, feed is 70 c/ha. Grass-mixed grass and grass-sedge-mixed grass lowland and swampy meadows on swamp-podzolic soils occupy 44%. Grass stands with the dominance of the sod pike are common. Swampy depressions are occupied by large-seeded grass stands. The yield of hay is 10–15 c/ha, feed is 9–11 c/ha. The ecological state of the province’s landscapes is satisfactory-tense.

Based on the modern method of agro-energetic evaluation of anthropogenic non-renewable energy sources and natural renewable resources, scientific evidence of high economic efficiency of green fodder production on cultivated pastures is presented. Two field experiments on improving the composition of grass herbage with the participation of domestic zoned varieties of ryegrass pasture and Festulolium, as well as similar grass mixtures with the inclusion of legumes: creeping clover and meadow clover were carried out. The total anthropogenic expenses were determined as well as the recoupment of their exchange energy by 3-4 and even 10 times in the produced forage. The role of natural factors in the structure of the received exchange energy was determined. This serves as a theoretical basis for the economic efficiency of indicators of cultivated pastures created by resource-saving technologies: mainly due to the longterm use of cereal grasses (for 14 years) or the receipt of biological nitrogen on legume-grass stands, which replaces the use of mineral nitrogen fertilizers in the dose N126-131 per year (average for 7 years) on dry grasslands of the Nonchernozem zone.

According to the data of the agro-landscape and ecological zoning of Eastern Siberia and the Far East, conducted by the authors, the spatial distribution of biological and ecological patterns in the East Sayan Mountain province was established. The province is located in the Eastern Sayan mountain system within the Southern Taiga zone. Its area is 17022.5 thousand hectares. Mountains occupy 76% of the province’s territory, plains – 24%. In the structure of land forests occupy more than 68% of the area of the province . Other land (mainly rocks and glaciers) occupies 20%. Under water is 3.4% of the area, swamps occupy 2.8%. Shrubs occupy less than 1%, mountain deer pastures – 0.8% of the area of the province. Agricultural land occupies 4.5% of the total area of the province. Including arable land – 0.9%, pastures – 2.6%, hayfields – 1%. The structure of natural forage lands (NFL) is dominated by mountain pastures on mountain soils (76%). The plains and foothills of the province are dominated by dry southern taiga meadows (13%). Floodplain meadows (5%) and swampy meadows (5%) are also represented. The ecological state of the province’s landscapes is good and satisfactory. In particular, NFL – good and satisfactory, forests – good and satisfactory, mountain deer pastures – good. The ecological state of arable land is tense. The established patterns are the necessary information basis for the development and implementation of innovative technologies for sustainable agricultural development, rational nature management and environmental protection in the East Sayan Mountain Province of Eastern Siberia and the Far East.