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Brinell hardness of steel 20 was measured with a ball of constant diameter according to the standard technique D=10 mm at different test load values from the range F=62.5…3000 kgf. The diameter d of the reconstructed indentation was measured. According to the developed method the deformation resistance of the sample material in the plastic zone bounded by a hemisphere was determined. The highest values of deformation resistance were recorded at indentation up to the ratio of d/D=0.245. Based on the results obtained, it is recommended to measure the Brinell hardness of steel 20 at the degree of loading F/D2=5. During the ball indentation process, the sample material undergoes significant deformation, which must be taken into account when measuring hardness.

Plasma chemical aquatermolysis of heavy oil feedstock allows increasing the depth of oil refining and the yield of light hydrocarbons. In the present work, the process of NTP-pyrolysis of a mixture of fuel oil with water (10 wt%) in the liquid phase at 700V was carried out. The introduction of water (10 wt%) into the fuel oil leads to changes in the conversion rate, product composition and energy consumption. Addition of 10 wt% of water to fuel oil increases the conversion rate from 18.6 to 25.9 wt% and reduces energy consumption. The main products are carbon materials, acetylene, ethylene and C3-C6 hydrocarbons.

NTP-pyrolysis of heavy petroleum products is a difficult task due to high viscosity, low hydrogen-to-carbon ratio and tendency to polycondensation with formation of high-molecular products. The use of oxygen-containing compounds for NTP-pyrolysis can reduce the yield of polycondensation products due to internal oxygen. In the present work, NTP pyrolysis of fuel oil in the presence of oxygen-containing additive (methyl tert-butyl ether) was carried out at a current source voltage of 700V. The influence of the content of the doping component in the range of 5-15 wt% on conversion, energy consumption and product composition was investigated. At increase in the content of methyl-tert-butyl ether up to 15 wt% in fuel oil the energy consumption decreases and the yield of gaseous products increases from 21.7 to 47.9 wt%. Carrying out NTP-pyrolysis process in the presence of oxygen-containing additive leads to an increase in the depth of processing of heavy fractions.

In recent decades, the Indentation Size Effect (ISE), which manifests itself as a change in fixed hardness depending on indentation conditions, has become one of the most urgent problems of modern materials science. Research efforts are aimed at identifying and eliminating the causes of ISE, because the discrepancy between actual and true hardness values greatly complicates the task of finding the optimal material for the manufacture of parts. The proposed paper gives a brief review of the theories explaining ISE and its relationship with hardness of materials. A more detailed analysis of the effect of ISE on hardness is presented using an energy model based on the determination of the specific work of plastic deformation during indenter indentation. In all cases of ISE manifestation, a proportional relationship was established between the fixed hardness and the specific work of plastic deformation. Thus, the main cause of ISE is the hardening of the material in the centre of deformation under the indenter. The degree of influence of ISE on the fixable hardness as a function of material pre-hardening was determined. At a high level of pre-hardening (at ε>0.25) the influence of the ISE becomes insignificant, so it cannot be of practical importance. The proposed method of hardness determination will allow to assign material for manufacturing of parts to a greater extent corresponding to the operating conditions.

Designing and creating a stable functioning ecosystem of the urban environment, endowed with individual features that meet the socio-cultural needs of residents of cities – large industrial centers, is an urgent problem of modern urban planning. The presence of accumulated technogenic impact and the need for rehabilitation measures are the conditions that must be considered when reconstructing and building this type of territory. The design and improvement of the urban landscaping center is a new approach to the use of existing urban areas, based on the principles of environmental friendliness, energy and resource efficiency.

The paper investigates the influence of the coupling coefficient of the double-loop filter forming a biharmonic oscillator on the quality factor and resonant impedance of the input impedance at the resonant frequencies of the double-loop filter. The resonant frequencies of the filter are exactly multiples of 2. In this paper show numerical results that simplify the choice of filter parameters to provide conditions for selfexcitation of two oscillations at exactly multiples of frequencies. Two synchronous modes allow to create a generator with compensation for fluctuations in the reactive component of the output impedance of the active element, which increase the phase noise of the oscillator.

The article presents an analysis of the foreign economic activity of agricultural producers in the Southern Federal District. The general results of foreign trade of the constituent entities of the Russian Federation located in the Southern Federal District are considered. The general characteristic of the foreign trade activity of the Southern Federal District is provided, providing for an assessment of the value volumes and per capita indicators of export and import, foreign trade turnover, and the balance of foreign trade balance.

The article analyzed the impact of foreign economic policy on the development of the Russian federal economy, considered the analysis of the commodity structure of exports and imports of the Russian Federation with the countries of far abroad and CIS countries, presented the analysis of agricultural products by farm figures in the Russian Federation for 2014 and 2018. Several trends have been proposed, which will allow to choose the correct strategy of development of Russia for the future.