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The authors consider the calculation of movement modes for unstructured suspensions in horizontal pipes. The movement mode in these cases is conventionally defined by the proportion of the concentration at the top of the pipe and in its middle. According to multiple authors, the flow carrying capacity is determined by its average velocity. This provides an opportunity to define the solid phase concentration profile along the vertical separately from solving the movement equations. This article presents an equation to determine the vertical distribution of the concentration obtained as a balance between turbulent pulses and the gravitation settling of solid particles. The analysis of solutions showed that there is a strong dependency between solid phase distribution and its average concentration in the flow. The comparison of movement mode calculation results obtained using the developed mathematical model and popular empirical dependencies showed good correlations. The obtained concentration profile can be used for the simplification of the general mathematical model of hydrotransport by predicting the motion mode and setting the concentration profile. This shall reduce the number of equations solved in the hydraulic fluid movement model and simplify the subsequent modeling of unstructured suspension movement in pipes.

Factors and tendencies regarding demography dynamics of Tambov oblast’ within the last seventy years, based on the Russian Statistics Office, are analyzed. The considered time period may be roughly divided into three ones, including the Soviet time period (1959–1991), the 1990s reforms (1991–2000), and the current time period (2001–2022). Each of them has some unique features that define the population of Tambov oblast’. The correlation of the overall birth rate and overall death rate, as well as the intensity and direction of migration flow influenced by socio-economic conditions within the region, are found. Recent changes in the social sector and in the regional economy are found to be insufficient to overturn the population decline, which serves as partial evidence of a discrepancy to the criteria of development sustainability.

Specific features of neuromorphic systems construction and aspects of basic elements functions realisation are discussed. Hardware implementations of basic elements of pulsed neuromorphic optical system - synapses and neurones - based on the phase state change of thin-film structures made of chalcogenide materials under the influence of laser pulses are described. Calculations of optical characteristics of GeSbTe thin films in multilayer structures have been carried out. The hardware implementation of the main functions of optical neurons was analysed on the model with multilayer coatings based on phase-changeable materials.

Analysis of the optical properties: refractive index n(λ) and extinction coefficient k(λ), of thin films of phase-change materials obtained by photometric and ellipsometric methods allows to optimize optical characteristics reflection R, transmission T and absorption A. The interference of an electromagnetic wave in an absorbing thin film on a dielectric substrate significantly affects the values of the optical characteristics. Optimization of the optical characteristics is possible through the use of additional layers of dielectric materials, which are used to compensate for the difference in the refractive indices of the film with the substrate and air and minimize the reflection. This approach will increase the contrast of the transmission levels for the modulated optical signal in near infrared range. Calculations of the optical characteristics of thin films of germanium telluride in multi-layer structures are performed. Experimental samples of structures with antireflection layers of zinc sulfide have been prepared and their optical transmission characteristics have been investigated. The combination of multilayer structures for the implementation of contrast levels of transmission have been determined.

One of the important parameters that determine technical solutions in the design of roads in the permafrost zone is the depth of thawing of the road foundation soils. The aim of the work was to quantify the degree of influence of the ice content in the soil foundations of roads in the permafrost zone on the depth of their seasonal thawing. For the analysis, we used the classical formula for calculating the thawing depth for bodies of plane symmetry, obtained by solving the single-phase Stefan problem. The results of numerical calculations are presented in the form of 2D and 3D graphs, which make it possible to visually assess the effect of ground ice content and the degree of its change during the road operation period on the depth of thawing of the road foundation. It has been established, in particular, that the degree of change in the depth of thawing at the same value of the increase in ice content in different ranges (for example, from 10 to 20% and from 30 to 40%) for the considered typical case of the ground base of the permafrost zone, decreases by almost 1.3 times. It is shown that the greater the initial ice content of the soil, the lower the degree of decrease in the thawing depth when the ice content changes by a constant value.

The expected thaw depth of the foundation soil is one of the parameters influencing the selection of technical solutions of road design in the permafrost area. The purpose of this research is a quantitative assessment of the degree of influence of air temperature on thaw depth of the road foundation soil in the permafrost area. A standard formula to calculate thaw depth of melting bodies of flat symmetry obtained through a solution of the one phase Stefan problem at boundary conditions of the first kind was used for the analysis. An algorithm using an analytical formula to assess the influence of the main initial parameters and accuracy of their determination on the resulting value, the thaw depth of the soil, is proposed. The results of the calculations are presented in a graphical form displaying the influence of average air temperature and the accuracy of its setting on the thaw depth of the road foundation soil. It was determined that the degree of change in thaw depth is non-linear and depends on both the average air temperature and on the accuracy with which it is set. For every average air temperature value there is a specific measure of required accuracy for thermal calculations so that the error of thaw depth determination does not exceed the permitted error. A 3D chart showing the expected percentage error in thaw depth forecasting depending on the average air temperature and the accuracy of its setting for an array of initial values was created.

The seasonal temperature and humidity regime of the road foundation in the active layer of soil largely determines the reliability and safety of the automobile road use. The aim of this article is a quantitative assessment of the influence of variation in ice content in the active layer of the road foundation soil in the permafrost area on the depth of seasonal soil thawing. Analytical solutions of one-phase flat Stefan problem at varying ice content along the coordinate were obtained. The solution is in the dimensionless form as a Fourier function based on Stefan number and dimensionless simplexes. The dependence of ice content change on the distance was assumed to be linear. Calculations using the obtained formulas were conducted, comparing against formulas assuming that ice content is a constant. It was determined at which ice content gradient averaging the ice content does not lead to an error greater than permitted in engineering practice in determination of the thawing depth. The results of variant calculations are presented as 2D and 3D charts to assess the influence of the initial ice content in the soil and the degree of its variation over the period of road use on the thawing depth of road foundation.

Technical structures with a parallelepiped form are frequently used in various areas of industry. For example, as fluid containers, ice and minerals piles, underground and surface storages and cooling chambers. A task of determining the optimum dimensions of the structure to minimize the energy expenses to support a normative temperature in the structure arises. The minimum surface area of the structure at a given volume is accepted as a criterion of optimality. A problem of unconstrained optimization for a structure with a parallelepiped form was formulated and solved. Equations to determine the optimum dimensions of width, height and length of the structure were obtained. It was determined that a cube is the most optimal form.

One of the most extensively studied silicate systems with complete miscibility in the solid and liquid state – albite (Ab)-anorthite (An) system – has been analyzed in detail. It has been established that the commonly accepted system and interpretation rules for these diagrams do not match their graphic representation. Calculations have proved the colloidal state of the “solid” phase on the solidus. Actual data support the colloidal (liquid) state of the solidus phase below the solidus and eutectic point. Crystallization in multicomponent systems, at least in silicate melts, has been shown to be based on the sol coagulation mechanism. Thus, silicate solid phases, even those of fixed composition, have no particular melting point. They consolidate and melt within a temperature band. The bandwidth is subject to the system composition that predetermines the micelle structure and directly affects coagulation and peptization processes.

Thermal resistance of the structural layers of a road is one of the important parameters that determine the choice of technical solutions of road design in the permafrost area. The purpose of this research is a quantitative assessment of the influence of the extent to which the pores in a gravel bedding are filled with ice or sand on the thermal conductivity of an ice-gravel or sand-gravel mixture. Lichtenecker formula was used to calculate the thermal conductivity coefficient of a three-component mixture. Different levels of ice content and moisture levels ofthe sand in the pores were considered. It was shown that the thermal resistance of the road structure can change significantly depending on the choice of the filler material. This allows to regulate the thermal regime of the road without adding new structural layers. The results of the calculations are presented as 2D and 3D charts to assess the influence of the filler material and the extent to which the pores are filled on the thermal conductivity coefficient of the mixture. The charts allow to see the possible changes in thermal conductivity coefficient of the structure and make a correct decision regarding the technologies to be used in construction. For example, to decide on the necessity to use a special thermal protection layer in the road structure.

A correct consideration of the thermal factors during the design phase of civil engineering structures in the permafrost area determines their reliable and safe exploitation. Among the important indicators in selection of design solutions is the thermal conductivity coefficient of the construction materials used. The thermal conductivity coefficient is usually chosen from reference tables, but when using mixtures, the thermal conductivity coefficient is determined through a calculation. The aim of the present research was to compare the calculated values of thermal conductivity coefficient of binary mixtures (a mixture of a binding material and a filler) obtained using Lichtenecker and Schwerdtfeger formulas. The comparison was conducted in the range of properties of materials used for thermal accumulation and thermal insulation mixtures. It was determined that for thermal accumilation binary mixtures the calculation results are quite similar within a wide range of initial values. For thermal insulation binary mixtures, the calculation results are significantly different. The divergencies are by hundreds of percents. At the current stage of research it is impossible to make a conclusion about suitability of either calculation method to determine the thermal conductivity of a thermal insulation binary mixture.

Парцеллят и сегмент – нетривиальные синтаксические позиции словоформ, участвующие в выражении субъективных смыслов. Обе позиции выделяются по отношению к базовой части: парцеллят обычно следует за ней, а сегмент ей предшествует. Парцелляция и сегментированная синтаксическая конструкция (именительный темы) являются важными грамматическими механизмами, которые позволяют субъекту речи в соответствии с коммуникативной целеустановкой адекватно выразить ту или иную мысль.

By a process of field studies of roads in the cryolithic zone the main types of defects and destructions of asphalt concrete pavements related to mechanical load from vehicle wheels were identified. The dominant types of deformations that form in warm and cold seasons of the year, as well as factors causing them, were determined. It was found that, regardless of the temperature in any arbitrary transverse road profile, the load on the traffic rut from the car wheel has an impulse character. The frequency of the impulse action depends on the speed of the vehicle, the number of axles and the distance between the axles. The amplitude of impulses depends on the weight of the vehicle and the evenness of the pavement.The unsuitability of regulatory documentation on load calculation for practical application was proved.

The article presents the materials of microbiological studies of the contents of the uterus of cows with acute catarrhal-purulent form of postpartum endometritis. Studies have shown that the microflora was represented by Proteus vulgaris, Escherichia coli, Staphylococcus aureus, Streptococcus faecium, Citrobacter freundii, Streptococcus pyogenes. The antibacterial activity of microflora to the drugs Enroflor®, Geomicini® F and Mitrec® was studied. The results of use of drugs for the clinical recovery of animals, the restoration of sexual cyclicity in cows were analyzed. The features of fertilization of cows after intrauterine use of various drugs for sexual cycles and for the entire duration of the experiment were studied. It was found that the highest therapeutic efficiency in the treatment of cows with acute catarrhal - purulent form of postpartum endometritis is provided by drug Mitrec®.

The article deals with the correlation of some of the most significant categories of criminal procedure activity: “purpose”, “purpose” and “tasks”. The authors conclude that without goals and objectives, it is impossible to imagine any organized, well-coordinated and planned activities, especially those regulated by law. The goal organizes the participants in the criminal procedure activity, advises them about the result, while the tasks help them to exercise their powers. The unity of purpose and objectives, which forms the goal-setting of criminal proceedings, attaches cohesion and coherence to the actions of numerous subjects, i.e. builds a capable system. Therefore, any process, including law-making and law enforcement, can and should be characterized from the point of view of its purpose and objectives. This indicates the objective need to establish not only the purpose, but also the goal setting in the law. The attempt to concentrate the tasks of the criminal process solely on the protection of the rights and legitimate interests of the individual (Article 6 of the Code of Criminal Procedure) seems unproductive. This provision is true, but it is not sufficient, since it does not take into account the state tasks that are initially present in such branches of public law as criminal procedure law and the criminal proceedings regulated by it. The criminal process cannot fulfil its purpose without taking into account the tasks of criminal law. By implementing them, criminal law and criminal procedure protect, among other objects, the life, health, interests and freedoms of citizens, as well as public order, public security, the constitutional system of the state, peace and security of mankind.

A new method of anchoring underground structures in permafrost areas, utilizing full anchors whose locks are based on the property that dispersed frozen rocks can significantly change their firmness depending on temperature, is considered. A new condition of energy efficiency of the use of this method is formulated. Simple engineering formulas, on whose basis the assessment of the non-productive and productive energy expenses during the formation of the anchor lock, were devised. It was determined that in many cases relevant for practice, the non-productive energy expenses can constitute up to 30% of the productive energy expenses. A conclusion was made that in order to increase the efficiency and to expand the area of application of the new anchoring method in the mine workings of the permafrost areas built in the dispersed frozen rocks, it is necessary to search for technical and technological solutions to decrease the non-productive energy expenses in the front part of the anchor lock.

Local exhaust ventilation allows maximizing the localization of hazards with minimum values of air exchange in the room. For the study, the design of a local exhaust in the form of an air-jet hood at an open doorway of the UKM Classic M 2005 chamber by Mauting was adopted. Geometric models have been developed, including a heat treatment chamber, a room from which the chamber is loaded, a supply and exhaust hood over the door from the chamber to the room, and a supply air duct with air distributing devices. The results of a computational experiment on modeling the operation of the local exhaust ventilation system of the heat treatment chamber are presented. The STAR-CCM+ software package was used as a calculation program. The calculation results were analyzed. The influence of the air exchange scheme (location of the supply devices) in the room on the efficiency of the local exhaust devices (supply and exhaust hood) has been established.

It is known that during the whole life cycle of a building it is necessary to take a responsible approach to the organization and management of construction processes at the present stage of construction. The reasons for the low use of construction waste were analyzed. It is shown that screenings of concrete scrap are the least demanded. The results of researches connected with utilizing concrete scrap to obtain building composites with high functional, economic and environmental efficiency were reflected.

The possibility of recycling large-tonnage waste of heat power engineer-ing and mining industry in road construction is shown. Compositions of road-building materials were researched, containing siftings of rock grinding, fly ash, Portland cement, modified with a stabilizing additive of polymeric nature. X-ray phase analysis showed availability of quartz in fly ash, calcite, feldspars, goethite and X-ray amorphous phase, what is consistent with the data of infrared spectroscopy. By atomic emission spectrometry with inductively coupled plasma it was revealed that fly ash is latent-active and can be disposed in compositions in the presence of a stabilizing additive. The X-ray phase analysis of grinding siftings showed that it contains quartz, feldspars, chlorite, calcite and dolomite. The specific activity of natural radionuclides (226Ra, 232Th, 40К) of fly ash and grinding siftings was 248 and 110 Bq/kg, which allows using such waste in construction without restrictions. It was revealed that the initial mineral raw materials belong to multiphase polymineral systems; therefore, when modifying them with stabilizing additives, binding of finely divided particles should be taken into account. It was revealed that the optimal content of Portland cement and fly ash in samples is 8 and 10 wt.%. It was found that an increase in the mass fraction of fly ash in the composition of soil-concrete up to 30 wt.% leads to softening of the samples and a decrease in their strength characteristics.