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The shear flow instabilities under the presence of magnetic fields in the primordial disk can greatly facilitate the formation of density structures that serve as seeds prior to the onset of the gravitational Jeans instability. We evaluate the effects of the Parker, magnetorotational and kinematic dynamo instabilities by comparing the properties of these instabilities. We calculate the mass spectra of coagulated density structures by the above mechanism in the radial direction for an axisymmetric magnetohydrodynamic (MHD) torus equilibrium and power density profile models. Our local three-dimensional MHD simulation indicates that the coupling of the Parker and magnetorotational instability creates spiral arms and gas blobs in an accretion disk, reinforcing the theory and model. Such a mechanism for the early structure formation may be tested in a laboratory. The recent progress in experiments involving shear flows in rotating tokamak, field reversed configuration (FRC) and laser plasmas may become a key element to advance in nonlinear studies. [ABSTRACT FROM AUTHOR]

We highlight camphene–camphor–polypropylene plastic as a useful material for self-propelled objects that show aggregation while floating on a water surface. We consider self-propelled rods as an example of aggregation of objects characterized by non-trivial individual shapes with low-symmetry interactions between them. The motion of rods made of the camphene–camphor–polypropylene plastic is supported by dissipation of the surface-active molecules. The physical processes leading to aggregation and the mathematical model of the process are discussed. We analyze experimental data of aggregate formation dynamics and relate them to the system's properties. We speculate that the aggregate structure can be represented as a string of symbols, which opens the potential applicability of the phenomenon for information processing if objects floating on a water surface are regarded as reservoir computers. [ABSTRACT FROM AUTHOR]

Introduction. Clay soil is a multiphase, multicomponent aluminosilicate dispersed system with specific properties determined not only by its composition but also by the formation of coagulative and transition contacts (binds) between the soil particles. One of the methods of changing soil properties is the introduction of active mineral additives that promote the formation of phase contacts (binds) between soil particles as a result of the pozzolanic reaction. The effectiveness of using carbide sludge, which is a multi-tonnage lime-containing waste (the content of active calcium oxide reaches 56%) as an additive, has been proved. However, to date, the proposed mechanism of interaction in the «clay soil – carbide sludge» system is based only on the literature data and has not been experimentally verified. The purpose of this research is to study the mechanism of structure formation in the «clay soil – carbide sludge» dispersed system. Methods and materials. A soil model has been created by mixing saponite-containing material with sand, which corresponds to the composition and properties of sandy loam. The carbide sludge in the form of a suspension was selected from the sludge collector, dried to a constant mass and sieved. Microstructural analysis, differential thermal analysis (DTA), and X-ray phase analysis were used to study the mechanism of structure formation. Results and discussions. Based the results of the differential thermal analysis, there is a decrease in the intensity of the endothermic effect in the range of 460 to 470°C associated with the decomposition of calcium hydroxide in the treated sample. Additionally, an endothermic effect is observed at 750°C, which indicating the decomposition of calcium silicate hydrate. The results of differential thermal analysis are confirmed by X-ray phase analysis, which shows the presence of tobermorite group hydrosilicates in the reaction medium. The study of the microstructure of the analyzed mixtures revealed a decrease in the specific volume of pores with a diameter of 4–5 nm in the modified clay soil. This is associated with gelling from particles of new hydrate formations. Besides that, the volume of pores with a diameter of more than 6 nm increased, which indicates the process of

The progress in polymer science and nanotechnology yields new colloidal and macromolecular objects and their combinations, which can be defined as complex polymer materials. The complexity may include a complicated composition and architecture of macromolecular chains, specific intermolecular interactions, an unusual phase behavior, and a structure of a multi-component polymer-containing material. Determination of a relation between the structure of a complex material, the structure and properties of its constituent elements, and the rheological properties of the material as a whole is the subject of structural rheology—a valuable tool for the development and study of novel materials. This work summarizes the author's structural–rheological studies of complex polymer materials for determining the conditions and rheo-manifestations of their micro- and nanostructuring. The complicated chemical composition of macromolecular chains and its role in polymer structuring via block segregation and cooperative hydrogen bonds in melt and solutions is considered using tri- and multiblock styrene/isoprene and vinyl acetate/vinyl alcohol copolymers. Specific molecular interactions are analyzed in solutions of cellulose; its acetate butyrate; a gelatin/carrageenan combination; and different acrylonitrile, oxadiazole, and benzimidazole copolymers. A homogeneous structuring may result from a conformational transition, a mesophase formation, or a macromolecular association caused by a complex chain composition or specific inter- and supramolecular interactions, which, however, may be masked by macromolecular entanglements when determining a rheological behavior. A heterogeneous structure formation implies a microscopic phase separation upon non-solvent addition, temperature change, or intense shear up to a macroscopic decomposition. Specific polymer/particle interactions have been examined using polyethylene oxide solutions, polyisobutylene melts, and cellulose gels containing solid particles of different nature, demonstrating the competition of macromolecular entanglements, interparticle interactions, and adsorption polymer/particle bonds in governing the rheological properties. Complex chain architecture has been considered using long-chain branched polybutylene-adipate-terephthalate and polyethylene melts, cross-linked sodium hyaluronate hydrogels, asphaltene solutions, and linear/highly-branched polydimethylsiloxane blends, showing that branching raises the viscosity and elasticity and can result in limited miscibility with linear isomonomer chains. Finally, some examples of composite adhesives, membranes, and greases as structured polymeric functional materials have been presented with the demonstration of the relation between their rheological and performance properties. [ABSTRACT FROM AUTHOR]

Composite materials obtained by sintering glass microspheres are considered the promising ones for the underwater technology. The high indicators of the hydrostatic strength combined with the heat and sound insulation properties are due to the microspheres maintaining their shapes as close to the spherical as possible. The computer model of the temperature distribution is developed based on the physical and chemical conceptions of the glass composites structure formation by sintering the glass microspheres of sodium borosilicate composition and processing the experimental results of the temperature measurements. The modeling methodology is based on the principles of decomposition of the task by the researcher and ranking the temperature and time parameters. The ratio of the hydrostatic strength to the density of the samples is taken as a functional criterion and the software application is written in the Python language. The experimental setup that is used for sintering the glass microspheres enables to study the temperature fields and thermal deformation processes in real-time conditions. The coefficients of thermal conductivity of sintering are determined by the regular mode method. The results obtained are aimed at solving one of the most important scientific and practical issues of developing technologies for manufacturing glass composites for strategic purpose. [ABSTRACT FROM AUTHOR]

The early microstructural evolution process of alkali-activated materials (AAMs) paste plays a crucial role in determining its workability and mechanical properties, which are reflected in the paste’s rheological behavior. However, the rapid development of early rheological properties of AAMs seriously affected its application. The paper investigates the early time-dependent rheology of alkali-activated slag (AAS) by sodium silicate. The relationship between the distribution space of free water and the rheological properties of AAS is established, which is of great significance for adjusting the rheological properties of AAMs. The reaction process and macroscopic structural evolution of AAS were observed through hydration heat tests and rheological performance tests, respectively. Additionally, the ion content and free water in the AAS solution were measured using inductively coupled plasma-optical emission spectroscopy (ICP-OES) and low-field nuclear magnetic resonance (LF NMR) techniques. The findings indicate that the early structural development of AAS comprises two stages: the “suspension stage” and the “rapid hardening stage.” During the suspension stage (less than 15 min), an initial dissolution heat release peak appears in the hydration heat curve. At this stage, the gel products are in the preliminary stage of aggregation reaction, characterized by a loose structure and low free water content (less than 1 %) in the gel pores. However, during the rapid hardening stage (more than 15 min), the aggregation reaction gradually promotes the growth and interconnection of gels. The free water content in the gel pores increases rapidly, leading to the encapsulation of slag particles by the gels, thus forming a rigid structure.

Introduction. The research is aimed at obtaining a lime composition and coating based on it for the restoration of cultural heritage sites. Materials and methods. We used for study slaked lime (fluff) with an activity of 83%. Sunbo PC 1021 (a superplasticizer based on polycarboxylate ether), MasterGlenium 115 and Sika ViscoCrete-226 P were used as plasticizing additives. The cohesive strength of the coatings was determined by the axial tensile strength. Rheological properties were assessed by plastic strength, which was determined using a KP-3 conical plastometer. Results and discussions. It was revealed that the introduction of polysaccharide additives contributes to a sharp increase in plastic strength compared to the control composition. The additive Sika ViscoCrete-226 P has the greatest plasticizing effect. It was revealed that the qualitative mineralogical composition of lime composites is the same. However, analysis of X-ray diffraction patterns indicates an increase in the intensity of CaCO3 reflections, which indicates an increase in the carbonization front. Control samples contain higher amounts of portlandite. A slight increase in the width of the CaCO3 peaks is observed, which indicates the possible introduction of organic molecules into the calcite composition. A change in the parameters of the crystal lattice was established in samples prepared with slaked lime in the presence of polysaccharides. Conclusion. The absence of chemical interaction between lime and polysaccharides has been established. It has been shown that coatings based on lime compositions with the addition of polysaccharides are characterized by higher cohesive strength. A change in the parameters of the crystal lattice was established in samples prepared with slaked lime in the presence of polysaccharides.

The goal of the research is to evaluate the flavor and rheological compositions formed in the process of structuring gel-like solutions of various concentrations into individual processes of the technological scheme for the production of semi-finished products and complex interaction in the structure of the finished product, taking into account the use of gelling agents and dietary supplements. The article presents some features of the flow of physicochemical reactions that make it possible to describe the dynamics of the interaction of nutrients in the formed binary compositions of carbohydrate-fat structures of plant systems in the technological process.Methods. To carry out the tests, the potentiometric method was used and the pH of each sample was determined using the Expert-001-3pH device. Determinations of sugars were carried out according to GOST 8756.13-87 using the permanganate method; dry substances according to GOST 31640-2012; organoleptic assessment according to GOST ISO 6658–2015. Samples of semi-finished products containing 25–30% fruit and citrus juices, 0.1–0.5% freeze-dried aromatic plants, 0.3–0.5% berry or vegetable powders, 0.3–0.6% spices were the objects of the research.The results. It has been established that the use of cellulose and glycerin in the formulation of carbohydrate-fat binary compositions based on fruit, citrus juices, berry or vegetable powders and spicy-aromatic raw materials contributes to the formation of an elastic, delicate film structure and a complex of flavoring and aromatic substances, depending on the type of raw materials and VAD used. With an increase in the concentration of cellulose, the films become denser, and in combination with the main raw materials (juice, powders, spices), the amount of dry substances and extract content increase, the films become opaque and less elastic. It has been found that in all samples, with an increase in spicy-aromatic raw materials, the number of inclusions increases and the films acquire a mosaic appearance. For clarity of experiments, graphs of the dependence of the type of main raw material and VAD on the concentration of the recipe composition and the formation of the flavor and aromatic range have been presented.Conclusion. The experimental data and dependencies obtained will be useful when considering more complex processes of mass transfer, sucrose inversion, and destruction of protein-carotenoid complexes. The perception of flavor and density of edible films is complex: the balance between sweetness, extractivity and threshold values of sensory characteristics are the main criteria for the organoleptic quality of the films being developed. It increases with the concentration of VAD and the type of juices or powders used. A richer and more pronounced taste appears.

Homeostasis, a self-regulating process that aims for stability, is presented to be the most fundamental regulatory principle of the psyche. Stability, or avoiding the extremes, is crucial for survival. The mind operates on different layers of homeostasis. Freud's three phylogenetic layers and regulating principles, namely nirvana, constancy, and psychic structure, are reviewed here. The self-image and its identity of perception form the core of the structure. In a clinical context, a cure that deviates too much from the self-image is perceived as threatening stability. The therapeutic relationship is an ideal setting for fostering the ego's mentalization capacity and the development of psychic structure. This paper demonstrates how mentalization and autonomous self-regulation challenge pathologic homeostatic regulation through clinical examples. The defensive resistance to cure, with its intriguing deep unconscious phylogenetic roots in homeostatic regulation, underscores the practical implications of these theoretical viewpoints in a clinical setting. [ABSTRACT FROM AUTHOR]

The objective of this study is to investigate the formation of the structure and stress–strain state in the joints of AISI 304 stainless steel with a thickness of 2 mm and produced by welding with laser and plasma energy sources. It is established that the microhardness and parameters of the grain and subgrain structures of the welded joint material differ with respect to the dimensions of crystallites, grains, and subgrains according to the welding process. It is shown that, in terms of structure formation, including substructural features, the most favorable structures of 2 mm AISI 304 welded joints are formed by laser–plasma welding. It is predicted that the residual stressed state is less localized with the application of laser–plasma welding than laser welding, and it is characterized by a lower level of residual stresses compared to plasma welding. In all the cases, the maximal stress values are concentrated in the HAZ, and the value obtained using laser–plasma welding is in an intermediate position (431.7 MPa) between those of the laser (443 MPa) and plasma (413.7 MPa) processes. With laser–plasma and laser welding, displacements (deformations) are minimal and close to 0.2 mm. The method of electron speckle interferometry was used, and the results reveal that the error between the calculated and experimental values of equivalent stresses is no more than 6%, which is acceptable. The results of mechanical testing show that, under uniaxial tension, the strength of the welded joints made of AISI 304 steel using laser–plasma and laser welding is the highest and equal to 97% of that of the base metal. [ABSTRACT FROM AUTHOR]

Drying is a critical process step during battery electrode production due to its microstructure defining nature. Distribution and interconnectivity of active material particles, pores, and the overall porosity significantly influence the later cell performance. Knowledge about structure formation as well as electrode property prediction are crucial for optimization and targeted electrode design. However, the exact microprocesses during electrode drying are not yet understood well and very difficult to access experimentally. Therefore, in this study, a combination of computational fluid dynamics (CFD) and discrete element method (DEM) simulation models for investigating structure formation considering particle–particle as well as fluid‐particle interactions and vice versa is presented. , The volume of fluid method is used for taking into account the fluid‐fluid interface, evaporation and capillary interactions. The simulations reveal the formation of a top–down consolidation front which interacts with the fluid leading to a backflow of liquid. The results show good agreement with experimental measurements for NMC622 cathodes. Furthermore, the influence of production parameters such as mass loading and solids content is examined. The findings demonstrate the modeling tool's suitability for process engineers to anticipate and enhance electrode characteristics and facilitate scientists to understand complex structure formation relationships. [ABSTRACT FROM AUTHOR]

Abstract Thermoactive binders are the most widely used form of polymer matrix materials in modern composites. In the production of composites, thermoactive binders are the basis of the matrix structure formation process with different properties. Various thermoactive binders based on epoxy, polyester and other resins compatible with corresponding polymer matrices were examined in the article. The influence of binders on the pre-molding process, various properties of the products, including density, stability and water permeability, as well as the main characteristics of composite materials obtained by various methods, was considered. The most optimal thermoactive binder (epoxy resin) were determined. The influence of thermoactive binders was shown and the advantage of using thermoactive binders in the production of composites was proved on the example of bitumen asphalt.

The article substantiates the possibility of obtaining composite materials with improved functional properties to strengthen the subgrade, containing technogenic soil stabilized by an additive based on a gelling polymer. The introduction of technogenic soils into composites will not only reduce the consumption of expensive materials, but also solve a complex of acute environmental problems. Composite materials can be used in the construction of structural layers of road pavements, foundations of buildings and structures, sites for various purposes, for the prevention and elimination of defects in the foundations of engineering structures during their construction, reconstruction and repair, including in permafrost areas. Stabilized technogenic soils are more durable, frost-resistant and waterproof, which makes them applicable for creating impervious curtains in hydraulic structures and sealing storage facilities for hazardous substances. The cryogenic effect on a composite material allows one to vary its properties within a wide range and modify its macroporous structure. Studying the process of structure formation of the resulting organic-inorganic materials, consisting of macromolecules of high-molecular substances and inorganic inclusions that have undergone cryogenic treatment, will make it possible to specifically regulate their performance characteristics. The best values of strength characteristics were obtained for samples with a stabilizing additive concentration of 100 g/l. The resulting composite materials are hydrophobic, frost-resistant, characterized by a compressive strength of 2.3–6.5 MPa and a thermal conductivity of 0.19–0.20 W/(m·K). Data from differential scanning calorimetry and thermogravimetry and IR spectroscopy revealed that the binding of mineral particles by a stabilizing additive occurs due to the formation of organomineral complexes with the participation of clay minerals and the restructuring of hydration shells. SEM data indicate that crystallinity zones formed due to hydrogen bonds of hydroxyl groups of neighboring polymer chains can participate in the formation of the composite structure. An increase in the number of cryogenic treatment cycles promotes additional structuring and strengthening of the polymer phase due to the formation of additional nodes of the supramolecular network, ordering of crystallinity zones and the appearance of compacted areas in the structure. Computed X-ray tomography revealed an increase in the density of the composite upon drying, which helps to increase its strength characteristics. The structure of the sample is characterized by heterogeneity of the pore space, which is characterized by the presence of both fine-porous and large-porous regions, which determines its thermophysical properties.

This paper explores the fundamental cosmological principle, with a specific focus on the homogeneity and isotropy assumptions inherent in the Friedmann model that underpins the standard model. We propose a modified redshift model that is based on the spatial distribution of luminous matter, examining three key astronomical quantities: light intensity, number density, and the redshift of galaxies. Our analysis suggests that the model can account for cosmic accelerated expansion without the need for dark energy in the equations. Both simulations and analytical solutions reveal a unique pattern in the formation and evolution of cosmic structures, particularly in galaxy formation. This pattern shows a significant burst of activity between redshifts 0 < z < 0.4, which then progresses rapidly until approximately z ≈ 0.9, indicating that the majority of cosmic structures were formed during this period. Subsequently, the process slows down considerably, reaching a nearly constant rate until around z ≈ 1.6, after which a gradual decline begins. We also observe a distinctive redshift transition around z ≈ 0.9 before the onset of dark-matter-induced accelerated expansion. This transition is directly related to the matter density and is dependent on the geometry of the universe. The model’s ability to explain cosmic acceleration without requiring fine tuning of the cosmological constant highlights its novelty, providing a fresh perspective on the dynamic evolution of the universe.

We highlight camphene–camphor–polypropylene plastic as a useful material for self-propelled objects that show aggregation while floating on a water surface. We consider self-propelled rods as an example of aggregation of objects characterized by non-trivial individual shapes with low-symmetry interactions between them. The motion of rods made of the camphene–camphor–polypropylene plastic is supported by dissipation of the surface-active molecules. The physical processes leading to aggregation and the mathematical model of the process are discussed. We analyze experimental data of aggregate formation dynamics and relate them to the system’s properties. We speculate that the aggregate structure can be represented as a string of symbols, which opens the potential applicability of the phenomenon for information processing if objects floating on a water surface are regarded as reservoir computers.

The shear flow instabilities under the presence of magnetic fields in the primordial disk can greatly facilitate the formation of density structures that serve as seeds prior to the onset of the gravitational Jeans instability. We evaluate the effects of the Parker, magnetorotational and kinematic dynamo instabilities by comparing the properties of these instabilities. We calculate the mass spectra of coagulated density structures by the above mechanism in the radial direction for an axisymmetric magnetohydrodynamic (MHD) torus equilibrium and power density profile models. Our local three-dimensional MHD simulation indicates that the coupling of the Parker and magnetorotational instability creates spiral arms and gas blobs in an accretion disk, reinforcing the theory and model. Such a mechanism for the early structure formation may be tested in a laboratory. The recent progress in experiments involving shear flows in rotating tokamak, field reversed configuration (FRC) and laser plasmas may become a key element to advance in nonlinear studies.

In this paper we review the possible mechanisms for the production of primordial black holes (PBHs) during a slow-reheating period in which the energy transfer of the inflaton field to standard model particles becomes effective at slow temperatures, offering a comprehensive examination of the theoretical foundations and conditions required for each of formation channel. In particular, we focus on post-inflationary scenarios where there are no self-resonances and the reheating epoch can be described by the inflaton evolving in a quadratic-like potential. In the hydrodynamical interpretation of this field during the slow-reheating epoch, the gravitational collapse of primordial fluctuations is subject to conditions on their sphericity, limits on their spin, as well as a maximum velocity dispersion. We show how to account for all conditions and show that PBHs form with different masses depending on the collapse mechanism. Finally we show, through an example, how PBH production serves to probe both the physics after primordial inflation, as well as the primordial powerspectrum at the smallest scales. [ABSTRACT FROM AUTHOR]

The article studies the influence of the temperature field on the formation of foamed silicate materials based on different wastes, such as glass cullet and ash-slag waste. Calculations of the batch composition for the production of foamed materials were carried out. The samples were synthesized, and their physical properties were studied. It was discovered that the processes during heat treatment of porous silicate materials can be divided into two qualitatively different stages: a low-temperature heating until sintering and a high-temperature heating from sintering to melting. The effect of temperature field distribution on the dynamics of porous structure formation was described. The dependence of viscosity on temperature for different types of waste was studied. The temperatures at which the porous structure is formed were determined. The influence of foaming agent on foaming intensity was discussed. Practical conclusions on adjusting a temperature and raw materials' composition to obtain a uniform porous structure were made. [ABSTRACT FROM AUTHOR]

Calcium monoaluminate was synthesized by the sol–gel method and the effect of europium and neodymium oxides on the synthesis and structuring kinetics was studied in the temperature range 500 – 1000°C. It was determined that the formation of the structure of calcium monoaluminate occurs at 1000°C and with exposure for 4 h of a xerogel obtained based on a mixture of Al(NO3)3 + Ca(NO3)2 at a compound ratio of 2 : 1, respectively. In the sample obtained, the intermediate mineral is mayenite Ca12Al14O33. With the introduction of the mineralizing europium oxide Eu2O3 in an amount of 1.5 wt.% greater than 100 wt.% in Al(NO3)3 + Ca(NO3)2 composition, at a synthesis temperature of 1000°C, the exposure time for maximum formation of calcium monoaluminate is reduced to 1 h. In samples containing Nd2O3, for the maximum formation of calcium monoaluminate at the same exposure time, it is necessary to introduce it in an amount of 5 wt.%. [ABSTRACT FROM AUTHOR]

This paper explores the fundamental cosmological principle, with a specific focus on the homogeneity and isotropy assumptions inherent in the Friedmann model that underpins the standard model. We propose a modified redshift model that is based on the spatial distribution of luminous matter, examining three key astronomical quantities: light intensity, number density, and the redshift of galaxies. Our analysis suggests that the model can account for cosmic accelerated expansion without the need for dark energy in the equations. Both simulations and analytical solutions reveal a unique pattern in the formation and evolution of cosmic structures, particularly in galaxy formation. This pattern shows a significant burst of activity between redshifts 0 < z < 0.4, which then progresses rapidly until approximately z ≈ 0.9, indicating that the majority of cosmic structures were formed during this period. Subsequently, the process slows down considerably, reaching a nearly constant rate until around z ≈ 1.6, after which a gradual decline begins. We also observe a distinctive redshift transition around z ≈ 0.9 before the onset of dark-matter-induced accelerated expansion. This transition is directly related to the matter density and is dependent on the geometry of the universe. The model's ability to explain cosmic acceleration without requiring fine tuning of the cosmological constant highlights its novelty, providing a fresh perspective on the dynamic evolution of the universe. [ABSTRACT FROM AUTHOR]

A series of mixed oxides was synthesized by deposition of the guest phase on the highly dispersed oxide matrix. Fumed nanooxides SiO2, Al2O3, SiO2/Al2O3, and SiO2/Al2O3/TiO2 with the specific surface area of 65–91 m2/g were selected as highly dispersed matrices. Co–Fe mixed oxides with the general formula Co4xFexOy (Co: Fe = 4: 1) were deposited as the guest oxides using the two-step method: (i) solvate-stimulated modification of the surface of fumed nanocarriers with the mixture of cobalt nitrate (II) and iron (III) formate and (ii) subsequent heat treatment up to 600 °C to form Co4xFexOy. The aim of this paper was to study the influence of the composition and structure of fumed oxide matrices and deposited guest phase on the morphology of the resulting composites in the gaseous and aqueous media using the XRD, XPS, FTIR, nitrogen adsorption and SEM/EDX, as well as quasi-elastic light scattering (QELS) methods. The low-temperature nitrogen adsorption isotherms have a sigmoidal shape with a narrow hysteresis loop characteristic of mesoporous materials. The specific surface area (SBET) of the composites varies from 48 to 82 m2/g, showing a tendency towards a decrease in the SBET values by 10–26% in comparison with the initial nanocarriers. The SEM data show the denser aggregate structure of nanocomposites compared to the initial carriers. The primary particle size was in the 30–60 nm range and the EDX data confirm the formation of a guest phase on the mixed aluminosilicate carriers, mainly in the surface patches corresponding to the alumina structure. According to the QELS data, there is a tendency to form aggregates of 100–10 μm in size in the aqueous media. The XRD method shows that the deposited metal oxides are in the form of crystalline phases of Co3O4 with the crystallites of 25–26 nm in size for the individual SiO2 and Al2O3 nanocarriers and 34–37 for the mixed ones, but the iron oxide reflections were not identified for the composites. XPS observation demonstrates the signal of Fe 2p electrons as the form of Fe2O3 oxide in the surface layer of nanocomposites as well as Co 2p as the Co3O4 and Co(OH)2. [ABSTRACT FROM AUTHOR]

This paper covers the design of binder formulations and technology for low-energy building materials based on alkaline aluminosilicate binders developed for special uses. The microstructure of the binders was investigated using scanning electron and atomic force microscopy examination techniques. The identification of phase compositions was performed by means of X-ray diffraction. The degree of binding of the alkali metal ions within the binder was determined with the help of chemical analysis of the pore fluid. Structure formation depending upon binder mix design and curing conditions was also studied. Some examples of the manufacture and application of binder-based glues and adhesives, including those developed for heat insulation and fire prevention, are discussed. The advantages of binder-based temperature-insulating composite materials compared with traditionally used materials are highlighted. [ABSTRACT FROM AUTHOR]

Knowledge of drying history and structure formation is essential for the quality of spray dried products. In this study, these factors are investigated using the denaturation of phycocyanin. By studying the denaturation kinetics of this marker, added to the feed solution, it was found that denaturation can neither occur in the constant drying rate regime nor in the final stage of drying, as the temperature (T < 60 °C) and the moisture content (aw < 0.6) is too low, respectively. Thus, it was concluded that phycocyanin denaturation is influenced by the crust formation during spray drying. This was applied to pilot scale spray drying, where the effect of air inlet and outlet temperature, air moisture content, feed solids content and particle residence time was investigated. The qualitative agreement between phycocyanin denaturation and the determined particle structure provides a basis for the validation of models, predicting structure development during drying. [ABSTRACT FROM AUTHOR]

The results of laboratory tests for obtaining high-quality waterproofing ceramic bricks based on low-grade loess loam are presented. Due to the recommendation of a new method of mass preparation, an improvement in the parameters of the brick-forming process has been achieved. [ABSTRACT FROM AUTHOR]

In further elaboration of her revised drive theory (briefly summarised here), the author develops the economical and structural-theoretical conditions of the unconscious. The focus is on the quantitative and qualitative aspects of the two opposing drive energies, the libido of the sexual- and life drive, and the lethe of the preservative- and death drive. The former is understood to have a tendency towards the conscious, the latter a tendency towards the unconscious. Each structure (from the micro to the macro level) is conceived as a combination of the representations of both drives; their interaction, which guarantees the dynamic stability of the psyche (pleasure principle/homeostasis), is organised in the structures. This applies both to the individual representation (e. g. self, object) and to the psychic instances (e. g. id, ego, superego), as well as to the linking of representations in memories, fantasies or dreams. With recourse to Lewin’s concept of the (mostly unconscious) empty, white or black dream screen onto which (consciously available) dreams are projected, the author proposes to assume for each representation a libidinal foreground tending towards consciousness and a lethic backside tending towards the unconscious. According to this conception, the unconscious is a component of all psychic processes. At the same time, the unconscious of the first topology and the id of the second topology would then be predominantly invested with lethic drive energies, while libidinal investments would predominate in the conscious parts of the ego and superego/ego ideal. [ABSTRACT FROM AUTHOR]

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Scenarios of structure formation in four-component nanoparticles are considered. The objects of study were Au-Cu-Pd-Pt nanoparticles containing N = 400, 800, 1200, 1600, 2000, 4000 atoms of the stoichiometric composition Au3CuPd12Pt4. Two alternative modeling methods were used: the molecular dynamics and the Monte Carlo. The interaction between atoms was described by the tight binding potential. The phase transition temperatures for the nanoparticles under study were determined. It has been established that the melting and crystallization temperatures depend both on the size of nanoparticles and on the rate of temperature change (by using the molecular dynamics method). The melting rate of nanoparticles has little effect on the melting temperature, while increasing the cooling rate significantly reduces the crystallization temperature and slows down the segregation processes. The process of coalescence of two four-component nanoparticles was modeled. During the process of coalescence, significant mixing of atoms of different types does not occur when using the Monte Carlo method, which leads to some stopping of the growth of the neck at the point of contact, in contrast to molecular dynamics method, where the growth of the neck occurs gradually.

The final configurations obtained during crystallization in ternary metal nanoalloys Tix-Al96-x-V4 of various compositions were studied. The molecular dynamics method was used as an atomistic simulation method. Interatomic interaction was described by the tight-binding potential. The size dependence of melting temperatures, as well as changes in melting and crystallization temperatures with changes in the composition of ternary nanoparticles, have been determined. Based on the results of a series of computer experiments, differences in the crystallization scenarios of Tix-Al96-x-V4 ternary nanoparticles were established. A classification based on internal structure and degree of crystallinity was proposed and tested. For Tix-Al96-x-V4 ternary nanoparticles, five main classes are identified based on the number of (semi) axes of 5th order symmetry. Despite the fact that studying the segregation of components of Tix-Al96-x-V4 ternary nanoparticles was not the goal of the work, atomic configurations corresponding to different temperatures during the cooling process were constructed and described.

In this work, scenarios of structure formation in ternary nanoparticles based on platinum and palladium of four stoichiometric compositions of different sizes were studied, with nickel acting as a dopant. Two alternative methods were used: the molecular dynamics method (implemented in the open source software LAMMPS) and the Monte Carlo method (implemented in the Metropolis scheme). In addition, to describe the interatomic interaction, two versions of force fields were used: the modified tight-binding potential (when implementing the molecular dynamics and Monte Carlo methods) and the embedded atom potential (when implementing the molecular dynamics method). Based on the results of a series of computer experiments, it was found that palladium atoms have increased segregation to the surface. At a cooling rate of 0,1 K/ps, an ordered crystalline FCC structure with inclusions of the HCP phase is formed. With an increase in the nickel dopant content to 20% in the ternary Pd-Pt-Ni nanoparticle, the identifiable local structure becomes more complex, both in terms of the number of phases and in terms of structural segregation.

The melting and crystallization phase transitions in the five-component metallic Au-Ag-Cu-Pd-Pt equiatomic nanosystem were investigated. The complex approach to atomistic modeling is due to the use of alternative methods of computer simulation – the molecular dynamics and Monte Carlo methods. The interatomic interactions were described by the tight-binding potential. According to the results of a series of computer experiments, it was established that five-component nanoparticles of equiatomic composition can form crystalline phases during cooling. Melting and crystallization temperatures for the investigated five-component nanoparticles were determined. The values obtained by alternative methods are in good agreement. For five-component nanoparticles, the concept of fixing the temperatures corresponding to the beginning and end of the phase transition process is confirmed. The metals that make up five-component nanoparticles, the atoms of which in the process of crystallization form the central part of the nanoparticle (core) and the peripheral regions, including the surface of the nanoparticle, are determined.

This work is devoted to the problem of thermal stability of mono- and binary metal nanocages consisting of gold and silver atoms. The number of atoms in the studied nanocages was 1744, 2150, 2470 and 3370 atoms. The characteristic size (outer diameter) of nanocages is from 4,4 to 5,1 nm. Interatomic interaction was described by the tight-binding potential. Analysis of the caloric dependences of the specific potential part of the internal energy made it possible to identify the temperature regions of «healing» of cavities (pores) on the faces and in the internal regions (cores) of nanocages. An example of the structural collapse of a nanocage is described in detail, as a result of which crystalline and quasicrystalline phases are identified in the nanoparticle core for a temperature corresponding to melting for the chosen size. Segregation in a binary Au-Ag nanocage before and after its collapse was also studied.

ABSTACT: Introduction. Research to improve the quality of foam concrete products through targeted control of technological processes of structure formation of cement-based compositions is relevant. The strength of foam concrete is significantly influenced by the adhesion strength of the hardened cement paste to the aggregate. This article discusses methods of chemical and mechanochemical activation of foam concrete filler with glyoxal-containing additives, interaction with hydration products of binders and increasing the strength of the contact zone. The quality of foam concrete can be improved by controlling the properties of the contact zone. Materials and methods. The study was conducted using standard test procedures specified in national standards. Results. With preliminary chemical and mechano-chemical exposure of the sand surface to glyoxal-containing additives and its subsequent introduction into the foam concrete mixture the grade of strength of foam concrete increases to B1 while maintaining the average density grade D500 in comparison with foam concrete of the control composition, while the shrinkage value decreases by 20–38.5% and thermal conductivity coefficient by 37%. Conclusion. The use of glyoxal-based additives in foam concrete mixtures by pre-activating the sand surface can improve the quality of cement foam concrete.

ABSTRACT: Introduction. This article presents the results of the research works on formation of building gypsum plaster porous structure with the use of recovered anhydrite raw materials and chemical additives, and describes a method for production of wall materials. The relevance of this paper is stipulated by the need to expand the range and increase the manufacture of heat-insulating and structural-heat-insulating products based on gypsum binders and local mineral raw materials, as well as the development of technologies to ensure the production of gypsum materials with improved performance. The authors proposed certain methods for forming the porous structure of building gypsum plaster and improving its performance in terms of porosity and thermal conductivity through the use of modified recovered raw materials and chemical additives of calcium chloride and sodium carbonate. Materials and methods. The study of the effect of modifying additives on the properties of the mixture was carried out using gypsum paste of normal consistency (NC = 55%). The preparation of samples and testing were performed according to the methods specified in the national standards with the use of porous additives of calcium carbonate, fluoroanhydrite and chemical additives for the rheological properties of the mixture, average density and strength of the samples, the patterns and mechanism of the processes of gypsum stone structure formation were established. Results. The application of fluoroanhydrite modified in the disintegrator with an equimolar amount of calcium carbonate leads to a decrease in the average density of the samples to 40% with evenly distributed pores. The analysis of the microstructure of heat-insulating material samples with a density of 550 kg/m3 showed that the average diameter of micropores is 0.45 mm, while the thermal conductivity of samples with complex chemical additives has the thermal conductivity coefficient of 0.25 W/m°C, which is 30% lower than the thermal conductivity of samples without complex additives. Conclusions. The results obtained create the basis for using recovery raw materials and domestic modifying additives as a pore-forming agent, which allow regulating the structure of gypsum stone in order to produce effective wall materials

In this paper we review the possible mechanisms for the production of primordial black holes (PBHs) during a slow-reheating period in which the energy transfer of the inflaton field to standard model particles becomes effective at slow temperatures, offering a comprehensive examination of the theoretical foundations and conditions required for each of formation channel. In particular, we focus on post-inflationary scenarios where there are no self-resonances and the reheating epoch can be described by the inflaton evolving in a quadratic-like potential. In the hydrodynamical interpretation of this field during the slow-reheating epoch, the gravitational collapse of primordial fluctuations is subject to conditions on their sphericity, limits on their spin, as well as a maximum velocity dispersion. We show how to account for all conditions and show that PBHs form with different masses depending on the collapse mechanism. Finally we show, through an example, how PBH production serves to probe both the physics after primordial inflation, as well as the primordial powerspectrum at the smallest scales.

Currently, additive technologies, in particular, electric arc growth as the most universal and productive, are used to produce individual machine parts. The problem of studying the process of structure formation in alloys during electric arc additive growth to ensure the necessary parameters of the microstructure of a material and its mechanical properties is challenging. 09G2S steel samples for research are fabricated on a developed test bench implementing the technology of 3D printing by electric arc surfacing, microstructural studies on an optical microscope are used, and microhardness measurements are carried out. The features of structure formation in a 09G2S alloy during additive electric arc growth have been determined, and controlled parameters have been identified to ensure the necessary parameters of the structure and, consequently, the mechanical properties of the alloy. The heat input of the surfacing process and the temperature of a thermal cycle are found to play a significant role in the structure formation in the material. The conducted research and established dependences make it possible to control the structural state of 09G2S steel during cladding to ensure the required parameters of its microstructure and mechanical properties. [ABSTRACT FROM AUTHOR]

The possibility is studied for a controlled structure to be created by varying parameters of the laser powder bed fusion (LPBF) process when using austenitic stainless steels as an example. On the basis of the results of studying the structure of experimental samples, the influence of a combination of various technological parameters included in the scanning strategy when preparing a 3D-model for the LPBF process on the structure formation processes is demonstrated. The possibility of formation of fragments with different structures within a single part in the course of its manufacture by the LPBF method via changing the processing parameters included in the scanning strategy is shown. It is noted that the use of 3D-models, identical in shape but different in the strategy used for laser beam scanning straight in the laser melting process, leads to the formation of a sample with a profoundly different structure, since microstructure formation strongly depends on metal crystallization conditions directly linked with the scanning strategy. [ABSTRACT FROM AUTHOR]

The standard model of cosmology,, has been successful in describing many observations. With the improvement of the number and the accuracy of observations, some inconsistencies among key cosmological parameters of the model have emerged. Many alternative models are proposed to alleviate these tensions. On the other hand, some observations of peculiar velocity show higher values than expected in a universe which may contradict the cosmological principle. In this work, we used linear perturbation theory to measure bulk flow and parameter in two alternative cosmological models and XCDM. We compared measured bulk flows with the predictions and some observations. We did a analysis to see which model is preferred by data. We find that model predicts higher bulk flows and is more consistent with observational data but does not reduce tension. Bulk flows measured in the XCDM model are lower compared to . However, this model can reconcile tension.

The objective of this study is to investigate the formation of the structure and stress–strain state in the joints of AISI 304 stainless steel with a thickness of 2 mm and produced by welding with laser and plasma energy sources. It is established that the microhardness and parameters of the grain and subgrain structures of the welded joint material differ with respect to the dimensions of crystallites, grains, and subgrains according to the welding process. It is shown that, in terms of structure formation, including substructural features, the most favorable structures of 2 mm AISI 304 welded joints are formed by laser–plasma welding. It is predicted that the residual stressed state is less localized with the application of laser–plasma welding than laser welding, and it is characterized by a lower level of residual stresses compared to plasma welding. In all the cases, the maximal stress values are concentrated in the HAZ, and the value obtained using laser–plasma welding is in an intermediate position (431.7 MPa) between those of the laser (443 MPa) and plasma (413.7 MPa) processes. With laser–plasma and laser welding, displacements (deformations) are minimal and close to 0.2 mm. The method of electron speckle interferometry was used, and the results reveal that the error between the calculated and experimental values of equivalent stresses is no more than 6%, which is acceptable. The results of mechanical testing show that, under uniaxial tension, the strength of the welded joints made of AISI 304 steel using laser–plasma and laser welding is the highest and equal to 97% of that of the base metal.

In world practice, the need for high-strength concrete with an intensive gain of early strength is due to an increase in requirements for characteristics of concrete and the desire to shorten the construction period. Alkali-activated cement, based on soluble sodium silicates (SSS), can demonstrate high strength and rapid gain due to the nano-modifying effect of amorphous silica present in SSS. However, the problem with the effective use of such cement compositions is unsatisfactory short setting times. This work investigates the effect of modifying admixtures on the structure formation of alkali-activated slag cement (AASC), its physical and mechanical properties depending on characteristics of SSS and the basicity of the aluminosilicate component (precursor), which was changed by the ratio of the ordinary Portland cement (OPC) clinker and granulated blast furnace slag (GBFS). A positive synergistic effect was noticed from glycerol and trisodium phosphate, as the components of a complex admixture, to control the setting of AASC. This resulted in extending the initial setting time from 1 to 5 min to the values of 21–72 min. The compressive strength of 21–26.3 MPa by 3 h, 36.5–43.4 MPa by 1 day, and 84.7–117.1 MPa by 28 days was obtained. Proper shrinkage deformations were equal to 0.47–0.6 mm/m. It was shown that with an increase in the basicity of the aluminosilicate component, the properties of AASC increased both in the early and late stages of hardening. [ABSTRACT FROM AUTHOR]

The characteristic features of structure formation, physical and mechanical properties of composite steel plasma coatings have been studied. Ferritic steel 11Х18МВД was used as the material for coatings. Depending on the modes of gasthermal spraying a special porous coating structure is formed, which is one of their important characteristics. Under the optimal modes of steel 11X18MВД spraying the total porosity of the coating was 20…24 % and the maximum open porosity was 16…18 %. Usually the porosity plays a positive role, increasing the tribomechanical properties of the parts during their operation, especially in the lubrication medium. However, during the operation of tribotechnical coatings under conditions of abrasive wear, porosity can worsen the working characteristics of the parts, therefore under these conditions the additional heat treatment was applied to improve the operational properties of plasma coatings. It promoted a high adhesion and formation of the required composition and heterogeneous structure on the surface, thereby significantly improving the coating properties. The paper shows the expediency of combining the processes of gas-thermal spraying of plasma coatings with their subsequent diffusion saturation by means of chemical-heat treatment with chromium plating. After chromium plating at a temperature of 1100 °C and soaking during 3 h, the coating density increases and the number of micro voids in it decreases significantly, the structure becomes more uniform, the integrity of the coating increases. Chromium coating with the thickness of 10 µm is formed on the surface, the thickness of the diffusely saturated metal layer increases with a more uniform distribution of alloying elements along the depth. The study of the tribomechanical properties of the investigated coatings showed a significant improvement in their operational characteristics under conditions of various types of intensive wear. [ABSTRACT FROM AUTHOR]

The authors have studied the effect of a thermally modified additive based on peat TMT600 on the properties and structure of foam concrete of non-autoclave hardening and proposed a model of a fragment of the structure of the gas–solid–liquid interface and a model for the formation of a porous structure of foam concrete of non-autoclave hardening. The paper reveals the mechanism of the role of the foaming agent in formation of the porous structure of foam concrete. Tomography methods have shown that the real structure of foam concrete corresponds to the proposed models, as well as the achievement of a uniform distribution of pores by volume. It was established that in hydration after the dissolution of tobermorite and ettringite, the cement particles are recharged, and, consequently, the electrokinetic potential changes from positive to negative values. The mass transfer of particles is carried out not only by diffusion, but also by convection during foam formation. The accelerated movement of particles can also be carried out due to the electrostatic interaction of charges both on the surface of the foam and the peat additive. The geometry of the structural cells of the foam has the form of polygons, consisting mainly of hexagons and pentagons. As a result of the ongoing processes, a complex hierarchical structure is formed, in which the Plateau–Gibbs channels in the foam are calmed (clogged), forming a stronger skeleton, and after cement hydration, due to the recharging of the surface of the latter, an interpore partition of increased strength is eventually formed with a simultaneous uniform distribution of pores in foam concrete structure. The developed wall material has not only high strength, frost resistance, but also increased thermal insulation properties. The foam concrete obtained with the use of the TMT600 additive fully meets the seven fundamental criteria of the modern concept of building materials science, such as: technological availability and efficiency, energy and resource saving, environmental safety and natural compatibility, economic feasibility, ethical acceptability of practical application, aesthetic expressiveness and social orientation.

In this work, bimetallic Cu-Ag nanoparticles of five stoichiometric compositions of various sizes were studied by molecular dynamics method using a many body EAM potential. Regularities of the structure formation are established, their characteristic features are described. In particular, in compositions with 10, 70, and 90 at.% Cu content, after the melt cooling, typical fcc structures with intersecting atomic planes of the hcp phase are formed. In compositions of 30 and 50 at.% Cu, the fraction of identified phases does not exceed 20% of the total number of atoms. A tendency to the formation of a core-shell structure was revealed in the case of a high copper content, while in the case of a high silver content, a so-called onion structure is formed. Using the caloric curves of the potential term of the internal energy, the melting and crystallization temperatures were determined. It has been established that the concentration dependences of the melting temperature of bimetallic Cu-Ag nanoparticles have a minimum corresponding to the equiatomic composition for all sizes. For the crystallization temperature, both the concentration dependences and the size dependences are less pronounced, but the minimum value of the crystallization temperature also corresponds to the equiatomic composition for all sizes; with an increase in the size of bimetallic Cu-Ag nanoparticles, a slight increase in the crystallization temperature is observed.

Various types of configurations of the Au-Cu-Pd-Pt four-component nanosystem, including complex core-shell structures, have been studied. The Monte Carlo method was used as a simulation method, the interatomic interaction was described by the tight-binding potential, i.e. the Gupta potential. According to the results of a series of computer experiments, it was found that four-component nanoparticles of this system do not tend to form a core-shell structure, even though gold atoms have an increased surface segregation. The melting temperatures for the nanosystems under study have been determined. The obtained values are in the range from 1100 K to 1250 K and weakly depend on the composition of nanoparticles (the ratio of the number of atoms). A stoichiometric composition based on these metals was found, for which, during cooling, an FCC crystal structure with inclusions of the HCP phase is formed. However, no distinctive features in the nature of segregation for this stoichiometric composition have been established. All considered stoichiometric compositions in the studied temperature range were stable with respect to decomposition.

This work studied bimetallic nanoparticles Ni@Ag and Ag@Ni with the total number of atoms 4000 by the molecular dynamics method using the tight-binding potential. The pattern of segregation and structural formation is established and its characteristics are described. Based on the analysis of the behavior of the calorie curves of the potential part of the internal energy, the melting and crystallization temperature was determined. The data obtained suggest that the processes of segregation in Ni@Ag and Ag@Ni nanoparticles are associated with the nanoparticle stability. The silver shell loses its stability above 900 K, while the nickel core remains solid and retains its structure. At the same time, in Ni675@Ag3325 nanoparticles the processes of the surface segregation of the nucleus atoms were less pronounced, whereas in Ag675@Ni3325 nanoparticles silver atoms actively segregated onto the surface of the nanoparticle. The features and fundamental differences in the processes of melting and crystallization of these nanosystems, as well as the temperature ranges of their stability, are analyzed. The relationship between the degree of intensity of segregation processes of nanoalloys during modeling and the stability of these systems is shown.

ABSTRACT: Introduction. The article presents the results of studies of the effect of complex additive based on glyoxal on the properties of cement-based foam concrete mix and foam concrete of natural hardening. The relevance of the study is determined by the necessity to provide the required process parameters of mixture for transportation and laying the formwork, as well as providing strength and thermal and physical characteristics of wall structures for the development of the northern regions of Russia, including the Arctic zone. It has been proposed to decrease the shrinkage deformations of the concrete mix and increase compressive strength of hardened foam concrete by affecting the cement matrix with complex modifier based on glyoxal. Materials and methods. The effect of modifying additives on the properties of the foam concrete mixture and foam concrete was studied at a W/S mixture ratio of 0.45. Research has been carried out using test methods set out in national standards. The results of the study of the effect of complex modifying additives (CMA) based on an aqueous solution of glyoxal and organic acids on the rheological and strength properties of foam concrete are presented, the regularities of the processes and the mechanism of structure formation of the modified foam concrete are determined. Results. The use of modifying additives leads to increase result in increasing the aggregative stability and reducing the plastic shrinkage of the foam concrete mix by 22–70%. In foam concrete with the complex additive LA 0.5% + Gl 0.55% the compressive strength rises from 1.96 to 2.43 MPa at the age of 28 days while maintaining the average density of D600. The thermal conductivity coefficient of foam concrete modified with various additives decreased by 5–30% compared to references. Conclusions. The obtained results of the study create in the construction industry the basis for the import substitution of modifying additives on the domestic mineral resource base and the production of effective structural and heatinsulating concretes for the development of the northern regions of Russia.