The parameters of the porous structure and the outer surface of cobalt catalysts for the synthesis of Fischer-Tropsch, promoted by magnesium, prepared by the impregnation method according to moisture capacity, were studied. The effect of polymorphic modification (γ, θ, α) of the carrier on the physicochemical properties of the catalyst Co-Mg / Al2O3 was studied.

Keywords: Fischer-Tropsch synthesis, polymorphic modifications of Al2O3, synthetic motor fuel, catalyst, carrier, elemental analysis, BET method, specific surface, porous structure

This paper contains an analysis of the modeling results of the electrophysical parameters of light-emitting GaInAsSb / GaSb solid solutions. The model takes into account three types of current - drift, thermionic emission and tunneling through potential barriers. In the work, graphs of radiation power versus current strength and current-voltage characteristic (IVC) of the LED device are plotted. Modeling indicators based on the features of the band structure of semiconductor systems have been built. Experimental results were discussed, which showed satisfactory agreement with the data obtained on the basis of calculations.

Keywords: solid solutions, Sim Windows 1,5, radiating structures, currents limited by space charge, electrophysical parameters

Developed approaches to measure the structural organization of systems. The concept of entropy expands and acts as an asymmetric criterion for the systems complexity. The necessity of a nonequilibrium approach to describing the interaction of physical structures and the possibility of interpreting entropy as a measure of the structural diversity of systems is shown. The validity of this approach is confirmed by a number of examples of the evolution of different systems, the structural distributions of the elements of which play an important role in modeling physical and physicochemical processes. Theoretical aspects are based on the fundamental work of D. Gibbs and L. Boltzman. The information content of the entropy concept correlates with the well-known “complementary” factor - coentropy. In this work, the evolution curves of complex systems are constructed as dependencies on statistical diversity. The symmetry of the functions of the density of entropy and coentropy with respect to the bifurcation points is discussed. It is shown that two-phase systems “liquid – vapor”, “crystal – melt” are characterized by inversion of evolutionary trajectories.

Keywords: entropy, negentropy, koentropy, orderliness measure, structural variety, normal distribution, dissipative systems, asymmetric structure, orthogonal distributions, dependence inversion

The paper presents a systematic review of recent advances in the development of polymer-matrix nanocomposites containing fibrous (sepiolite-palygorskite group) and non-swelling (kaolinite-serpentine group) clay minerals, as well as their modified forms obtained using surface reactions with organic and inorganic substances. An analysis of scientific trends and the current status of research in this area has been carried out, with particular emphasis on the influence of the types and forms of the considered mineral fillers on the properties of nanocomposites for various applications.

Keywords: polymer nanocomposites, clay minerals, kaolinite, halloysite, sepiolite, palygorskite

The article is devoted to the problem of theoretical research and development of perovskite-based solar cells to optimize their design and increase efficiency. The paper presents a numerical simulation of the transfer and accumulation of charge carriers in the planar p – i – n heterostructure of a solar cell. The simulation is based on a stationary physico-topological model based on the diffusion-drift system of semiconductor equations. The efficiency of solar cells for different perovskite film thickness was obtained. It has been established that the maximum efficiency of the optimized design of a solar cell is about 27% with a perovskite film thickness of 500-700 nm and a defect concentration in it of the order of 1012 cm-3.

Keywords: Numerical simulation, solar cell, perovskite, film thickness, defect concentration, current-voltage characteristic

It has been established that the concentration of cholesterol mesogenic esters in lubricants ambiguously affects the microrelief parameters and the tribotechnical characteristics of a steel 45 – steel 45 friction pair. %, the best indicators of friction and wear of metals, on the contrary, are realized with an increase in the concentration of cholesterol esters in lubricating compositions.

Keywords: lubricant, cholesteric liquid crystal, microrelief on friction surface, coefficient of friction

The aim of the article is to analyze the existing methods for constructing a model of random errors in micromechanical sensors. A comparison of different methods for determining the parameters of a random process model is presented: autocorrelation, power spectral density analysis, time domain analysis, and Allan variation analysis. This direction is also supplemented by considering the effect of sensor errors on the error of inertial navigation systems. In conclusion, the synthesis of forming filters for various random errors in micromechanical sensors and the results of simulation are given.

Keywords: mems gyroscope; noise analysis; stochastic drift; error modelling

When developing any technology of repair it is necessary to conduct research mikrolitrazhnyh worn parts of assemblies using metrological equipment. At the moment to improve the accuracy of research the repair company should use the latest measuring system, allowing to carry out a full complex of works on profileration surfaces of worn parts. Such devices include for example profilograph profilometer English company "Taylor Hobson", which allowed to determine the amount of allowance for machining the body of the power steering distributor. As a result, using the data obtained, the technology of repairing the power steering of KAMAZ vehicles was developed.

Keywords: metrological equipment, profilograph-profilometer, micrometer, power steering, repair technology, recovery, wear, distributor, shaft

The paper considers an adaptive on-off regulator. A block diagram of this device is given, and the sequence of operation of the blocks is also described. Simulation modeling of various types of on-off regulators was carried out in order to identify their effectiveness.

Keywords: automation, adaptive regulation, regulators, simulation

Currently, one of the main problems of our time is to improve the ecology of the regions. Green areas can contribute to this, however, the southern region of Russia is caused by a dry summer period. In this regard, there is the task of ensuring high-quality irrigation, which is often carried out by automated systems. However, without feedback, it is extremely difficult to bring the process to the proper level of quality. To do this, use humidity sensors, the price of which inevitably leads to a strong appreciation of the system. This article discusses the possibility and feasibility of developing and implementing its own moisture sensor that would meet such positive criteria as low cost, high accuracy and wide range of measurements, high corrosion resistance, versatility of application.

Keywords: soil moisture sensor, automation, irrigation, capacitive measurement method, microcontroller, Southern Federal District

Economic-probabilistic method assesses the feasibility of tactics for MAINTENANCE and operating time and technical condition for buses equipped with electronic control units. The scheme of determination of limit values of diagnostic parameters is proved. It is shown that the implementation of the STATE is appropriate when the economic costs associated with the cost of diagnosing and forecasting the technical condition of the buses are not decisive.

Keywords: strategy, tactics, method, parameter, maintenance, repair, cost, reliability, operation, technical condition

On the basis of the mathematical apparatus of Queuing, a mathematical model for the diagnosis of the technical condition of vehicles with electronic control units. The developed mathematical model of vehicle diagnostics in the framework of discrete-event paradigm. Numerical experiments to assess the effectiveness of diagnostics are carried out.

Keywords: cars, electronic control unit, diagnostics, Queuing system, efficiency, operating costs

The article is devoted to the actual problem of overcoming the restrictions imposed by the IP Protocol and network technologies used in conjunction with it, in particular, address translation, on the structure of computer networks and the availability of its individual nodes. It proposes a method of building virtual network tunnels based on the principles of steganography using service network protocols, briefly describes the shortcomings of existing technologies of tunneling. The paper describes in detail the proposed method of steganographic encapsulation of network packets, describes the principles of formation of packet headers, provides examples of protocols for encapsulation. The material of the article is presented consistently, competently and meets the generally accepted requirements for scientific works. The presented approach to solving the problem of building virtual tunnels has scientific novelty and has practical value.

Keywords: Encapsulation, Internet protocols, multilevel network models, steganography, steganographic packet encapsulation, tunneling

The method of layer-by-layer build-up of the material allows creating parts of complex configuration.To expand the field of application of such parts in the industry, it is necessary to know the properties of products obtained by this wayvery well. Currently, the literature sources do not provide enough information about the properties of products obtained by 3D printing on FDM-technologies.This is due to the variety of materials used and printing modes.Data on mechanical properties, such as tensile strength, bending, compression, shrinkage, specific weight of the material, will allow designing and creating real structures using 3D printing.The article considers the extrusion method of 3D printing, describes the study of tension, compression, bending, specific weight, shrinkage of samples with different structures obtained from ABS plastic.It is found that the deformation of the material during its tension depends on the number of filaments on the shell of the surface layer and reaches the highest values for samples containing eight and ten filaments. The calculation of the specific weight of the samples shows that the density of the samples with a tetrahedral structure is higher compared to the hexahedral structure at the same printing and filling modes. In determining the ultimate compressive strength of the samples, it is revealed: the higher the percentage of sample filling material, the more the sample withstands compressive stress. Experimental data on material shrinkage show that when filling the model with material from 20 to 80% shrinkage is 1%, and at 100% filling - 0.78%.

Keywords: additive manufacturing, 3D extrusion printing, mechanical property, FDM technologies, ABS plastic

Executed system analysis of the types of damage to logging machines and damage them in the manufacture. It is found that defects in material, shape and size of the part have a significant impact on the reliability of the equipment. The main attention is paid to the effect of crack-like defects. If as a measure of damage to take the length of the crack and apply the methods of fracture mechanics in the calculations, it will be obvious the relationship of operational and industrial damage. It is established that the main cause of failures of logging machine details of domestic production is not enough high quality of their production. It is recommended to use more widely such as characteristic of materials as fracture toughness to assess the reliability of the design.

Keywords: Logging machine, reliability, damage, manufacturing defects, fracture toughness