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We considered capabilities of electrochemical analysis for the determination of organic compounds in aqueous-organic and dispersed media. The main factors affecting the electrochemical characteristics of analytes and the contribution of the solvent nature to the operational and analytical characteristics of the corresponding sensors are determined. Several examples are given of the implementation of the advantages of electrochemical analysis using homogeneous aqueous-organic solutions, emulsions of organic solvents, and individual drops at an electrode–solution interface. Biosensors operating in the presence of organic solvents are also discussed.

Computer prediction of the migration of radioactive contaminants in soil is a promising scientific direction due to the fact that prediction of the radiation situation on the basis of experimental measurements of radionuclides activity requires the use of mathematical and computer methods of data processing. At the same time, most of the specialized software packages for predicting the spread of radioactive contaminants in soil are based on one- and two-dimensional idealizations of this process, while solving the problem of comprehensive assessment of the biosphere’s state requires the data of the contaminant’s spatial distribution. To obtain such data, the author has developed a software module as a part of SPS (Simulation of Processes in Soil) v2.0 software package, which allows predicting the parameters of the spatial migration of radionuclides in natural dispersed media. To assess the possibility of using the developed software in practice, the prediction results were verified by the experimental data. For this purpose, the spatial distribution of the Cs-137 concentration in the experimental area in the Luninets district of the Brest region was predicted using the measurement data of the Cs-137 activities and the soil characteristics. The comparison of the results obtained on the basis of experimental measurements and the predicted values of the spatial distribution of the Cs-137 concentration showed that the predicted values are within the confidence intervals of the measured values. Consequently, the developed software can be used to solve practical problems in the field of forecasting the migration of radionuclides with obtaining a reliable picture of their distribution over the volume of the modeling area and to comprehensively assess their impact on the environment.

A mathematical model has been developed for changing the dynamics of the movement of a dispersed medium in vibro-impact technological processes of shaping of powder metallurgy blanks. On the basis of the problem of two-dimensional dynamic interaction of dispersed particles of powder metal of a spacer dispersed medium, the obtained differential equation in partial derivatives under various boundary conditions. This equation describes the state of the local area of the dispersed medium. In it, the powder material of the workpiece passes from the concentrated dynamic force to the excitation phase. A partial differential equation is obtained. It describes the change in normal stress during vibrations of a dispersed medium during vibration compaction of a workpiece in powder metallurgy.

In the cationic polymerization of vinyl monomers water is generally avoided due to the reactivity of carbocations towards water as well as the high water sensitivity of the most commonly used Lewis acid catalysts. However, the development of various water tolerant Lewis acid catalysts has led to a number of reports of polymers synthesized by cationic polymerization directly in aqueous dispersed media. In this work we evaluate the fundamental limitations of cationic polymerizations conducted in water, highlighting the effects of inherent chain transfer reactions, whose importance is heightened at elevated temperatures, as well as the extent of chain transfer to water. The results suggest that cationic polymerizations conducted in dispersed media proceed under pseudo-bulk conditions and thus the molar mass of the polymer is dependent on the saturated water content of the organic phase, as well as the rate coefficient of chain transfer to water. For some monomers, such as styrene, it is shown that the effect of transfer to water is negligible and molar mass is largely determined by transfer to monomer reactions. However, for other monomers, such as β-pinene, attempts to polymerize in aqueous dispersed media result in almost exclusive formation of oligomers. While this work highlights that cationic polymerizations conducted in water are necessarily limited to fairly low molecular weights, the results show that in many cases polymers produced by cationic polymerization in dispersed media are within the range required in commercial applications.

The origin of organic matter, its spread, scattering, and functioning are influenced by the physical structure of liquid or dispersed media of organic matter. Refractive indices of fodder yeast grown on paraffin oil (paprin) and natural gas (gaprin) as well as Lycoperdon spore and organelles were measured by laser phase microscopy. The scattering matrices of aqueous suspensions of paprin, gaprin, and Lycoperdon spores were measured using a laser polarimeter with the scattering angle ranging from 20 to 150°. The experimentally measured scattering matrices have been approximated by the weighted sum of theoretically calculated scattering matrices using the T-matrix code developed by Mishchenko. Most of the particle radii in the filtered fraction of paprin and gaprin were within the range of about 0.05-0.12 μm. Particle radii of the Lycoperdon spore suspension were within the range of 0.4-2.4 μm, which corresponded to both whole spores and their separate organelles. A possibility of identifying a suspension by its scattering matrices was shown for a small difference in the real parts of the refractive index in the example of paprin and gaprin. The measurements of the light scattering matrix showed that for a small size parameter of about 1, the identification of paprin and gaprin can be based only on a difference in the particle shape. Refractive index difference is manifested for the size parameter values higher than 3. An example of a suspension consisting of micron-sized spores and their submicron organelles shows high sensitivity of the scattering matrix to the composition of the dispersed material. The presented data and models help to extrapolate the results of the light scattering matrix study to a vast spectrum of media of organic matter origin and functioning. This study focused on the Biogeosystem Technique (BGT*) transcendental methodology to manage soil as an arena of biodegradation and organic synthesis. A BGT*-based robotic system for intra-soil pulse continuous-discrete water and matter supply directly into the dispersed-aggregated physical structure of the soil media was developed. The system enables transformation of soil into a stable highly productive organic chemical bioreactor for better controlled nanoparticle biomolecular interactions and adsorption by biological and mineral media. The scattering matrix measurement unit is supposed to be used in the robotic system as a diagnostic tool for the dispersion composition of soil organic components.

The scientfc and technical problems of the power plants improvement have been systematzed. The urgency of the problem of the power plants purifcaton in the multphase dispersed media is proved. The main purifcaton methods are analyzed, and previously unstudied pieces of problem of these processes intensifcaton are identfed. The task for the calculatons of the scheme of complex intensifcaton of the ultraturbophoretc transferal within the combined (internal and external) problem is set. The unstructured grid technology for the theoretcal calculatons of the pulsaton ultrasonic partcles depositon in the multpurpose grid coagulator is suggested and implemented. The aim of work is to develop the directons of the purifcaton intensifcaton of the dispersed multphase fows on the basis of the study results analysis. These directons are to be developed to design the technical equipment which ensures the intensifcaton of energy conservaton and environmental cleanliness of the power plants. The processes of the transferal of the fnely-dispersed phase by means of the ultrasonic and turbophoretc powers in the two-phase gas media of the power plants are the subject of the study. The scheme of complex intensifcaton of the ultraturbophoretc transferal of the micropartcles of partcles is developed within the «the inital fow secton – ultraturbophoretc grid coagulator» purifcaton system on the basis of the performed analysis of physical and mathematcal model of the process. The principles of intensifcaton of the ultraturbophoretc transferal and fnely-dispersed partcles depositon are developed. These principles are reduced to the usage of the energy potental of the dispersed two-phase media to depose the partcles; to the creaton of the acoustc vibratons gradients in the wall-adjacent areas at the surface of the channels and in the fow volume; to the generaton of turbulent pulsatons by the bodies of depositon of the multfunctonal purpose.

The process of mixing of bulk materials in a newly developed continuous drum-blade mixer is investigated. The presence in cross-sections of the material of two zones of characteristic behavior of the material, an active mixing zone and a transporting zone, is established. (It is assumed that the parameters of these zones do not vary along the length of the mixer, but that the homogeneity of the mixture varies.) The mixing process is described by means of an isotropic approximation of the Fokker–Planck kinetic equation. The structure of the macrodiffusion coefficient is determined on the basis of well-known representations of the statistical theory of interaction of dispersed media. In accordance with a model, the results of the calculation exhibit satisfactory convergence with the results of an experiment.

This article will focus on water quality and quantity issues in foodproduction and in the factory. For food production, it is important to understandhow water demand, sources of pollution, water reuse and contamination offood through water affect food safety. The issues of the influence of the type andconcentration of the dense part of the suspension and the liquid phase used (water,milk, water-milk mixture 1:1), the formation of colloids is considered.

The technological features of the production and transportation of some solid finely dispersed products of the chemical industry require the use of an additional deaeration operation (compaction). This processing of powders affects the quality of the product, delivery conditions. The production of deaerated granules-spheres from mineral components and bitumen for the preparation of asphalt concrete mixture or from powders for the production of dry dyes is relevant. The aim of this work is the mathematical modeling of the deaeration (compaction) process of solid finely dispersed media in a gap with perforated hemispherical shapes on the surfaces of the shaft and conveyor belt within the framework of the mechanics of heterogeneous systems. The distinctive features of the proposed method for modeling mechanical deaeration, as a technological process, from the known classical models are as follows. First, the plane-deformation model is described neglecting the forces of interphase interaction. The model assumes consideration of the movement of: a) the components of the solid skeleton of the dispersed medium together with the carrying phase as a whole; b) gas in an isothermal state through the pores of a finely dispersed material. This work is devoted to the study of part (a), i.e. behavior of the solid particle-gas system as a whole. Second, the compressibility of the solid particle-gas mixture is taken into account in the absence of elastoplastic deformations of the particles themselves. The efficiency of the seal-deaerator for solid finely dispersed media is estimated using the obtained analytical dependencies for the main strength and speed indicators of the process under study. Using the example of the deaeration of kaolin, the change in the degree of compaction of the resulting sample of a spherical granule with specified strength characteristics is investigated. It is shown that for the initial time interval up to 3.7⨯10-2 s, the growth of the porosity value relative to the horizontal coordinate along the conveyor belt is exponential and increases by a factor of 1.1. After eight such time intervals, the porosity values stabilize along the indicated coordinate with an increase of more than 1.4 times from the initial value.

The performance of waterborne (meth)acrylic coatings is critically affected by the film formation process, in which the individual polymer particles must join to form a continuous film. Consequently, the waterborne polymers present lower performance than their solvent-borne counter-polymers. To decrease this effect, in this work, ionic complexation between oppositely charged polymer particles was introduced and its effect on the performance of waterborne polymer films was studied. The (meth)acrylic particles were charged by the addition of a small amount of ionic monomers, such as sodium styrene sulfonate and 2-(dimethylamino)ethyl methacrylate. Density functional theory calculations showed that the interaction between the selected main charges of the respective functional monomers (sulfonate–amine) is favored against the interactions with their counter ions (sulfonate–Na and amine–H). To induce ionic complexation, the oppositely charged latexes were blended, either based on the same number of charges or the same number of particles. The performance of the ionic complexed coatings was determined by means of tensile tests and water uptake measurements. The ionic complexed films were compared with reference films obtained at pH at which the cationic charges were in neutral form. The mechanical resistance was raised slightly by ionic bonding between particles, producing much more flexible films, whereas the water penetration within the polymeric films was considerably hindered. By exploring the process of polymer chains interdiffusion using Fluorescence Resonance Energy Transfer (FRET) analysis, it was found that the ionic complexation was established between the particles, which reduced significantly the interdiffusion process of polymer chains. The presented ionic complexes of sulfonate–amine functionalized particles open a promising approach for reinforcing waterborne coatings. This research was funded by the Industrial Liaison Program in Polymerization in Dispersed Media (3M, Akzo Nobel, Allnex, Arkema, Asian Paints, BASF, DSM, Inovyn, Stahl, Synthomer, Vinavil, and Wacker).

The paper presents the available experimental data on ice 0 and the assumed objects of the cryosphere in which it can exist. This ice is formed from supercooled volumetric water, and it precedes the formation of ices Ih or Ic, at temperatures below −23 °C. This crystalline modification has been recently predicted by computer simulations using methods of molecular dynamics. Ice 0 was then experimentally found by electromagnetic investigation of wetted nanoporous media. Interest in this modification of ice was aroused due to its special physical and chemical characteristics. A singularity of ice 0 is that it is a ferroelectric that has a high static dielectric constant. When ferroelectric ice 0 contacts other dielectrics at their boundaries a thin layer is formed due to the diffusion of electric charges, and its electrical conductivity is higher than that of the contacting media. High electrical conductivity in thin films allows investigating frozen dispersed media containing ice 0 using non-contact electromagnetic measurement methods. As this takes place, it becomes possible to register water freezing processes in objects existing at temperatures of −23 ÷ −100 C using microwave spectroscopy and remote sensing methods. It is assumed that ice 0 is involved in chemical transformations in different objects of the cryosphere – in the atmosphere, and vegetation and soil covers. Its formation in the pores of materials of man-made structures may exert influence on the life-time of mechanisms and structures at low temperatures due to increased electrocorrosion. Ice 0 is assumed to exist on cold planets and their moons. That is why studying the possibility of ice 0 appearing in different objects of the natural environment at negative temperatures is so important for understanding their properties and developing remote sensing methods.

The phenomenon of dilatancy is a unique property of dispersed media, and in the case of soils can have a significant impact on the shear resistance and the stress-strain state change during loading. In the conditions of free boundaries dilatancy leads to volume increase, and in the presence of volume expansion restrictions to the growth of average stresses. Thus, dilatancy leads to an increase in shear resistance, which makes it possible to increase the degree of use of the bearing capacity of the base. Many modern mechanical models of soil allow dilatancy calculation, most often on the basis of the Rowe’s theory, according to which the angle of internal friction changes during loading, and to calculate the base taking into account its hardening. In addition, the introduction of the plastic potential into the strength conditions allows the calculation of the final plastic strains. This is very important in case of complex loading trajectories, often implemented in soil foundations. The article provides an overview of dilatancy phenomenon studies in our country and abroad with main analytical dependencies given. Four main methods for determining the dilatancy angle are considered: the method of direct simple shear (DSS) and multiplane direct shear (MDS), triaxial compression and torsion shear, their main advantages and disadvantages are highlighted in a form of a table. It is shown that determination of the dilatancy angle does not present significant difficulties and does not require specialized equipment, at the same time, the effective use of this parameter in the design leads to economic effect, primarily in the case of sandy and coarse soils.

In mathematical modeling of the grain separation process during its cleaning the following approaches are used: deterministic, statistical and combined. Deterministic models demonstrate the influence of individual factors on the process. Assumptions made in these models can significantly distort the physical picture of the process. In the middle of last century there appeared the probabilistic approach which takes into account the diversity of random factors influence on the kinetics of vibroseparation. In this paper, a stochastical approach to modeling the process of grain separation on vibrating screens is developed and mathematical apparatus of Markov chain theory that effectively describes the evolution of dispersed media with random properties is proposed. Determination of the stochastic model parameters based on the experimental data of test experiments on the periodic classification of bulk materials allows adequately modeling and calculating continuous processes of industrial vibration separation of grain.

In this work, we demonstrate that machine learning methods can be reliably used to predict radiative properties of dispersed media, i.e. packed beds, as a function of packed bed geometry and material properties. The computationally expensive Monte Carlo ray tracing (MCRT) method, which is widely used in this context, is replaced by Neural Networks (NN). We demonstrate that the data-driven surrogate prediction works accurately and generally. The results of both MCRT and NN models agree well with each other and with previously measured literature results. We also measure the uncertainty of the NN results using statistical methods. It is recommended that the developed model be used for efficient inverse problems and optimizations in relevant future work.

This paper presents the study of optical properties of absorbing and scattering media. In order to determine changes in the optical properties of the studied media using the photothermal interference method, the digital interferometer scheme and related software were developed. It is shown that the developed photothermal interference method is characterized by high sensitivity and can be successfully used for rapid, non-contact, non-destructive determination of the parameters of absorbing and scattering media.

Recent developments in modelling of two-phase flows in vortex rings and vortex ring-like structures in gasoline engines are summarised. For the two-phase flows, the carrier phase parameters are assumed to be the ones predicted by the viscous vortex ring model presented in Chap. 3. The mixing of inertial droplets can be accompanied by crossing of droplet trajectories. Their number densities are calculated based on the Fully Lagrangian Approach. Two flow regimes corresponding to two initial conditions are investigated. These are injection of a two-phase jet and propagation of a vortex ring through a cloud of droplets. The ranges of governing parameters leading to the formation of mushroom-like clouds of droplets are identified. The caps of the mushrooms contain caustics or edges of folds of the dispersed media, which correspond to particle accumulation zones. The values of velocities in the regions of maximal vorticity, predicted by the generalised vortex ring model, are compared with the results of experimental studies of vortex ring-like structures in gasoline engine conditions. It is shown that most of the observed values of these velocities are compatible with the predictions of the model.

Studies of the process of electret charge generation in LiF crystals subjected to mechanical activation and evaluation of the role of color centers in this process were carried out. Accumulation of currents in the studied material in absence of external voltage is connected with electrical activity of the system and the generation of a stable internal electric field in this system. The electric field generated in a heterogeneous medium formed by fine-dispersed lithium fluoride and a water film, causes ionization of polar water molecules that produce conductivity channels. This leads to active electrical interaction of the surfaces of solid and liquid dielectrics included in structure of the system under study. The presence of radiation induced defects in the dispersed phase based on LiF influences the processes of interphase interactions. This contributes to formation of deep electron traps and increases the lifetime of the charge of electrets.

This paper focuses on polarized radiative transfer in dispersed layers composed of densely packed optically soft particles while considering the effects of dependent scattering and particle agglomeration. The radiative properties of the particles for different agglomeration degrees are calculated using the Lorenz-Mie theory combined with the Percus-Yevick sticky hard sphere model, and the vector radiative transfer equation is solved by using the spectral method. The normalized Stokes reflection matrix elements of the layers for different particle sizes, particle volume fractions and layer thicknesses are discussed. The results show that the effects of multiple scattering, dependent scattering and particle agglomeration have different degrees of influence on the polarized reflection characteristics of the layers. Due to the inhibition effect of far-field interference interaction on particle scattering, the dependent scattering weakens the depolarization caused by multiple scattering. However, as the particles form agglomerations, the scattering coefficients of the particles obviously increase with the agglomeration degree, which will lead to the significant enhancement of the multiple scattering and depolarization.

The review presents results of experimental studies in the range from 2 to 8.6 GHz of the dielectric properties of foam samples in the solid state. The results of experimental studies of variations in the dielectric properties of dispersed media in the form of samples of liquid water foam in wide bands of the microwave range are presented: 1). 2.5–3.5, 2), 5.6–8.3 and 3). 8-12 GHz. The results of multi-frequency measurement methods in the open space of reflection of electromagnetic waves in the range 17.4 - 25.9 GHz from a layer of water foam located on a metal substrate are reflected. The method of synthesizing the envelope of a radio pulse signal was used according to the measurement of the reflection coefficient. Shown are the variations in the relative dielectric pemability of the foam depending on the foaming ratio and time of existence.

Collisionless media devoid of intrinsic stresses, for example, a dispersed phase in a multiphase medium, have a much wider variety of space-time structures and features formed in them than collisional media, for example, a carrier, gas, or liquid phase. This is a consequence of the fact that evolution in such media occurs in phase space, i.e., in a space of greater dimensions than the usual coordinate space. As a consequence, the process of the formation of features in collisionless media (clustering or vice versa, a loss of continuity) can occur primarily in the velocity space, which, in contrast to the features in the coordinate space (folds, caustics, or voids), is poorly observed directly. To identify such features, it is necessary to use visualization methods that allow us to consider, in detail, the evolution of the medium in the velocity space. This article is devoted to the development of techniques that allow visualizing the degree of anisotropy of the velocity fields of collisionless interpenetrating media. Simultaneously tracking the behavior of different fractions in such media is important, as their behavior can be significantly different. We propose three different techniques for visualizing the anisotropy of velocity fields using the example of two- and three-continuum dispersed media models. We proposed the construction of spatial distributions of eccentricity fields (scalar fields), or fields of principal directions of the velocity dispersion tensor (tensor fields). In the first case, we used some simple eccentricity functions for dispersion tensors for two fractions simultaneously, which we call surrogate entropy. In the second case, to visualize the anisotropy of the velocity fields of three fractions simultaneously, we used an ordered array (3-vector) of eccentricities for the color representation through decomposition in three basic colors. In the case of a multi-stream flow, we used cluster analysis methods to identify sections of a multi-stream flow (beams) and used glyphs to visualize the entire set of beams (vector-tensor fields).

We have performed experiments on the influence of corona discharge plasma on samples of dispersed media with organic components (various types of soils). We have revealed the role of air ionization under the action of the corona discharge, which leads to a change in the electrical conductivity of media and to a change in the chemical properties associated with the oxidation of molecular nitrogen to its mineral forms.

The interaction of a cell with light is described by electromagnetic theory through parameters such as absorption cross-section, scattering cross-section and scattering phase function, which are essential radiative properties in radiative transfer theory for analysis of light transport in dispersed media. The radiative properties of microalgae vary with time due to the growth process of cell division and metabolism. In this paper, the growth-dependent radiative properties of Spirulina platensis (a microalgae with filamentous helix structure) was experimentally investigated in batch cultivation. The microalgae was cultivated in a flat-plate photobioreactor under dark and light cycle 12 h and 12 h with irradiance of 2000–2500 lx. The absorption and scattering cross-sections of Spirulina platensis were measured in the spectral region 380–850 nm at different growth time. The experimental results showed temporal scaling behavior of the radiative properties of this filamentous microalgae, which confirms the temporal scaling law of radiative properties of microalgae reported recently, namely, the temporal scaling function (TSF) defined as the ratio of spectral absorption or scattering cross-sections at different growth time to that at stationary phase is nearly wavelength independent. This paper is the first work on the temporal scaling behavior of radiative properties of Spirulina platensis, and also provides additional experimental evidence on the general validity of the temporal scaling law of radiative properties of microalgae cells.

A transient axially symmetric two-phase vortex-ring flow is investigated using the one-way coupled, two-fluid approach. The carrier phase parameters are calculated using the approximate analytical solution suggested by Kaplanski and Rudi (Phys. Fluids vol. 17 (2005) 087101–087107). Due to the vortical nature of the flow, the mixing of inertial admixture can be accompanied by crossing particle trajectories. The admixture parameters are calculated using the Fully Lagrangian Approach (FLA). According to FLA, all of the dispersed phase parameters, including the particle/droplet concentration, are calculated from the solution to the system of ordinary differential equations along chosen particle trajectories; FLA provides high-accuracy particle number calculations even in the case of crossing particle trajectories (multi-valued fields of the dispersed media). Two flow regimes corresponding to two different initial conditions are investigated: (i) injection of a two-phase jet; and (ii) propagation of a vortex ring through a cloud of particles. It was shown that the dispersed media may form folds and caustics in these flows. In both cases, the ranges of governing parameters leading to the formation of mushroom-like clouds of particles are identified. The caps of the mushrooms contain caustics or edges of folds of the dispersed media, which correspond to particle accumulation zones.

Aqueous dispersed media and films based on edible or succinate chitosan with single-walled carbon nanotubes (SWCNTs) were manufactured. Infrared spectroscopy and Raman spectroscopy were used to study the structural changes associated with formation of intermolecular junctions between chitosan and SWCNT. Nonlinear optical characteristics of liquid samples exposed to pulsed laser radiation of nanosecond duration were determined experimentally and calculated theoretically. The composition of the medium based on succinate chitosan and SWCNT providing the largest nonlinear absorption coefficient (902 cm/GW) was determined. The sample with this composition had lower threshold radiation intensity (2.7 MW/cm2), at which nonlinear effects are generated in the medium and liquid-to-solid transition occurs. The results obtained in this work are useful for laser-based production of three-dimensional cellular and tissue-engineered structures used in cardiovascular surgery.

The general issues of the development of an optimal circuit diagram of a vibration system and determination of the parameters of this circuit providing an extreme criterion of optimality are considered. The object of research is technical machines and technological media, which are considered as a system subordinated to a single vibration process. By technical machines, vibration machines adopted in the work for the implementation of compaction processes are adopted. Technological media adopted two-phase dispersed media used for compaction. Concrete mixes and soils are accepted by such media. Reducing energy costs, a high level and speed of energy transfer to the process are the main factors in creating optimal schemes of vibration systems. One of the most problematic places in solving this approach is the lack of a generally accepted model for the interaction of the working bodies of machines with the processing medium. Existing studies are based on the separate determination of the parameters of machines and media. Such methods are characterized by significant energy costs and a long duration of the process. The proposed approach based on the harmonization of the forces of machines and media arising in the vibration process, has significantly reduced energy costs. The work also obtained a new synergistic effect of the system. This is due to the fact that the proposed method for creating the optimal circuit has a number of features. So, in the course of the study, the modes of combining the elastic-inertial forces of the subsystems in a single system are used. Particular implementation of subresonance and superresonance modes are determined. Thanks to this, it is possible to maximize the effectiveness of vibration systems not only in new design solutions, but also in the targeted use of the internal properties of the integrated system. Compared with similar well-known vibrating machines, energy costs are reduced by 50 %. The proposed methodology for developing organizational principles for the formation of the optimal scheme and parameters is used in the design of vibration systems for vibration and vibration-shock modes of compaction of building mixtures.

In this work, we investigate quantitatively the applicability conditions of single scattering approximation (SSA) through direct simulation of electromagnetic scattering by small volume elements filled with randomly distributed spherical particles. The influences of size parameter x, volume fraction fv, complex refractive index m and number N of particles on the nondimensional extinction cross section ηext and absorption cross section ηabs of particle groups are discussed. For non-absorbing particles with small size parameters (x = 0.1 and 0.2 in this study), due to the small phase shift across particles, the particle refractive index has almost no influence on the criteria for SSA. However, when the particle size increases or particle absorption is enhanced, the criteria for SSA will be closely related to the particle complex refractive index. Moreover, when the particle size is small, due to the weak multiple scattering between particles, the criteria for SSA can be regarded as the criteria for independent scattering approximation (ISA). But as the particles increase to relatively large sizes (x = 4.0 in this study), because of the enhancement of multiple scattering, the criteria for SSA and ISA should be treated differently. The widely used criteria obtained for bispheres may not be applicable to particle groups composed of lots of particles, and the optical thickness of dispersed media is not suitable for evaluating the applicability conditions of SSA. For particle groups composed of different particle numbers, due to the differences in dependent scattering and multiple scattering, the criteria for SSA are obviously different and the particle volume fraction should be small enough to make the SSA sufficiently accurate.

The block diagram and the principle of action of a new measuring complex for determination of temperature and humidity of fibrous materials and dispersed environments based on dependence of dielectric characteristics of materials on their moisture content are described. The experimental results showing electrophysical characteristics of cotton materials are presented.

The new method for hardening ready-made steels, hard alloys and diamond tools is developed: low-temperature process for producing thin-film solid lubricant coatings by hydro chemical treatment in specially prepared aqueous media of nanosized hard refractory compounds and subsequent tempering. The main advantages of the method over known processes are presented. The principles for dispersion of refractory materials are formulated. The structure and properties of the obtained coatings are examined. The fields of high compression strains (180-470 МPа) are created in tool materials subjected to hydro chemical treatment. The new process permits decreasing the friction coefficient of tools surface in 3.8-12.1 and increasing the service life of steel, carbide and diamond tools by the factor of 1.5-8 as compared with untreated materials.

The monograph is devoted to the development of mechanical systems with dynamic effects on processing media. A new approach and methodology is proposed, taking into account the influence of energy fields of physical and me-chanical effects, the transformation and inversion of types of energy exposure. The model of dispersed media under consideration in the range of the process of destruction, grinding and compaction is considered. The revealed changes in the parameters of subsystems: working media, mechanical systems, the process-es of their interaction are studied based on the consideration of their stress-strain state. The analysis of combinations and their influence on the intensity of phy-sical and mechanical processes is carried out. The intensification of physical and mechanical processes, methods and means of their creation are achieved by the formulated idea: systematization and complexity of approaches through a joint consideration of the mutual influence of the internal properties of the subsys-tems made it possible to identify the general laws of their changes and take them into account in the work process. The movement of the working media during high-speed and impact destruction with differentiation of the working area is de-scribed. Structuring of the shock process, the formation of entropy destruction, the use of self-organization and the evolution of geometric shapes are evaluated. The process of grinding materials by a vibratory jaw crusher is investigated and methods for determining the effective parameters and their operation modes are proposed. The process of compaction of the processing medium in the field of vibrations in the device with spatial vibrations is described. The laws of change in the device movement, taking into account interaction with the processing medium are established. As a research result, new properties of the behavior of discrete-continuous systems under power load are disclosed. For the first time, stresses and strains are taken into account as working bodies and media for creating energy-saving vibration systems for compaction of building materials. The conducted scientific study makes it possible to obtain the laws of change in the state of dispersed media under the action of power loads by mechanical sys-tems. Minimization of energy costs and increase the efficiency of work processes is proposed when implementing various technological processes.

While the preceding chapters present the reactivity of metal clusters, elucidating the chemistry of condensed matter, studies of cluster reactivity also serve to reveal the microscopic aspects such as nucleation phenomena, formation of highly dispersed media like ultrafine particles and nanoscale materials/surfaces. It is anticipated that metal clusters especially those of superatoms will be significant building blocks to creat genetic materials.

International audience; Submicronic molecularly imprinted polymer (MIP) colloids were synthesized by polymerization in aqueous dispersed media for selective separation of nonylphenol (NP) organic pollutant. A miniemulsion polymerization process based on ultrasheared monomer droplets has allowed for dispersion of the hydrophobic organic pollutant template to produce water-dispersible colloidal MIP. Structural parameters of the cross-linked polymer particles were tuned during the synthesis to achieve the best compromise between good specificity of imprinted polymer (MIP) sorbent compared to nonimprinted polymer (NIP) (i.e., imprinting factor (α)), sufficient level of adsorption capacity (Q), and selectivity of MIP toward the organic pollutant. For that purpose, the polymerization takes place in the organic monomer droplets containing nonylphenol (NP), N-vinylcaprolactam (VCL), different comonomers (vinyl acetate (VAc), vinyl benzoate (VB), or 2-ethylhexanoic acid vinyl ester (VeoVa-EH)), and various contents of divinyl adipate (DVA) cross-linker. Tuning the level of hydrophobic interactions, either by the hydrophobicity of the comonomer (VeoVa-EH > VB > VAc) or by the polarity of the hydroalcoholic mixture used for interfacial adsorption, achieved imprinting factors above unity. The binding of NP follows a monolayer Langmuir adsorption, and the present MIPs selectively recognize NP compared to phenol. Isothermal titration calorimetry (ITC) measurements corroborated both specificity (ΔHMIP > ΔHNIP) and selectivity with very low values of binding enthalpy for phenol, p-cresol, and 1-octanol compared to that of NP.

This paper focuses on polarized radiative transfer in a thin layer composed of titanium dioxide particles while considering the effect of host medium absorption on particle scattering. The single-scattering properties of particles in an absorbing medium are calculated using the modified Lorenz-Mie program recently developed based on the first-principles theory of electromagnetic scattering, and the vector radiative transfer equation is solved by using the spectral element method. The relative errors of Stokes parameters caused by using the conventional Lorenz-Mie theory are systemically investigated. The results show that neglecting the effect of host medium absorption on particle scattering has a more significant impact on the radiation intensity than the polarization components in most cases. Meanwhile, the relative errors of Stokes parameters induced by using the conventional Lorenz-Mie theory obviously increase with the increase of the host medium absorption index and particle size parameter. Due to the larger scattering coefficients and scattering albedos (i.e., for the case of particle size parameter x=10.0 in this study), the relative errors of Stokes parameters of monodisperse particles are obviously larger than those of polydisperse particles. Moreover, it is found that the relative errors of the Stokes parameters change nonlinearly with the particle volume fraction, especially for large size particles.

The design was developed and a hardware-software measuring infrared thermography-based complex, which allows semi-automatic experimental research of the sorption dynamics and low-temperature catalytic processes during the interaction of various gases and their mixtures with solid-state highly dispersed materials, was created. The complex contains an optical-mechanical part and an automated gas supply system controlled via WiFi. Using the new-generation infrared thermography methods, the latent kinetics of phase transformations on the surface of highly dispersed samples with catalytic and non-catalytic properties has been experimentally investigated. The quantitative characteristics of fine-grained materials have been experimentally studied. Using the described methodology, a number of interesting phenomena taking place on the surface of highly dispersed media were experimentally revealed.

In this paper the processes of formation and decomposition of natural gas hydrates in wet salted sand samples were studied. Investigations of phase transitions were performed on a specially assembled DTA installation. It is shown that with decrease of the humidity and increase of the salinity of media the degree of supercooling decreases, and the amount of the gas bound to hydrate decreases. It has been found that in comparison with the water-gas system in dispersed rocks there is a shift of thermobaric conditions of hydrate formation to the area of high pressures and low temperatures.

The synthesis of poly(n-butyl methacrylate) by nitroxide mediated miniemulsion polymerization is described using the alkoxyamine 3-(((2-cyanopropan-2-yl)oxy)(cyclohexyl)amino)-2,2-dimethyl-3-phenylpropanenitrile. Polymerizations are successfully conducted to high conversions with high solids content (up to 52%) and molecular weight up to 60 000 g mol−1, whilst maintaining reasonable control of the reaction. It is shown that by performing the polymerization in aqueous media, problems that arise when targeting high molecular weights in bulk/solution due to build-up of nitroxide can be overcome. The ability to chain extend the resulting polymers is demonstrated and opens the possibility for synthesis of a wide range of macromolecular structures in dispersed media.

The evolution of an aggregate of particles embedded in a fluid phase, no matter whether a liquid, a vapor, or a mixture of both, is determined by the dependence of the equilibrium interface area on porosity volume fraction. In system with open porosity, this equilibrium can be analyzed using a model representing the particles as a collection of cones of revolution, the number of which is the average particle coordination number. The accuracy of the model has been assessed using in situ X-ray microtomography. The model makes possible the computation of the driving force for sintering, commonly called sintering stress. It allows the mapping of the domains of relative density, coordination number, and dihedral angle that bring about aggregate densification or expansion. The contribution of liquid/vapor interfaces is enlightened, as well as the dependence of the equilibrium fluid phase distribution on particle size. Applied to foams and emulsions, the model provides insight into the relationship between osmotic pressure and coordination. Interface-governed transport mechanisms are considered dominant in the macroscopic viscosity. Both sintering stress and viscosity parameters strongly depend on particle size. The capacity of modeling the simultaneous particle growth is thus essential. The analysis highlights the microstructural parameters and material properties needed for kinetics simulation.