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In this article, results are presented of experiments on depositing charged particles, which imitate the levitating dust on the Moon, on stainless steel. Ensembles of particles are created above the surface of laboratory regolith whose composition and particle size distribution imitate the dust that covers the Moon’s surface. Under the action of the gyrotron radiation on regolith, non-linear physical-chemical processes develop (breakdown, chain plasmachemical reactions, and particle scattering by the Coulomb mechanism), which lead to the appearance of a levitating cloud of particles. The simulation experiment is based on the similarity between the processes that develop in the laboratory experiments with regolith and the processes that occur on the Moon during its bombardment by micrometeorites. The effect of the levitating cloud on stainless steel plates is studied and it is shown that regolith particles in the shape of spheroids of different sizes are deposited on the surface of the plates. The dimensions of the deposited particles and the density of their placement depend on the quality of treatment of the plate surface. It is shown that the laboratory-produced dusty plasma can be used in simulation experiments to study the modification of surfaces of different materials for space technology.

A number of different geological and production parameters affecting successful acid fracturing are considered in the conditions of carbonate reservoirs of oil fields in Bashkortostan. The study results are of use for assessing the effectiveness of geological and technical measures and for a more reasonable choice of candidate wells for acid fracturing.

To date, an increase in the oil recovery factor by commissioning horizontal wells is of relevance for oil fields at the late exploitation stage. In most cases, horizontal wells are developed using multistage fracturing; therefore, it is crucial to determine the criteria affecting its successful implementation. The study results are of use for a more reasonable approach to the choice of the location of horizontal wellbores and increase in the efficiency of geological exploration and multistage hydraulic fracturing.

The energy of directed plasma flows accelerated in a current sheet is studied experimentally as a function of the current flowing through the sheet. It is found that the plasma flow energy rapidly increases with increasing current amplitude, nearly according to a power law with an exponent of 1.8–1.9. Using relations for the neutral current sheet and the concept of plasma acceleration under action of the Ampere forces, the energy of directed plasma flows is estimated as a function of the total current flowing through the sheet. It is shown that, as the current rises, the ion energy grows due to an increase in both the Ampere forces and the width of the current sheet within which plasma is accelerated.

The distributions of the ion temperature, ion pressure, and electron density over the width (the major transverse dimension) of the current sheet have been studied for the first time. The current sheets were formed in discharges in argon and helium in 2D and 3D magnetic configurations. It is found that the temperature of argon ions in both 2D and 3D magnetic configurations is almost uniform over the sheet width and that argon ions are accelerated by the Ampere force. In contrast, the distributions of the electron density and the temperature of helium ions are found to be substantially nonuniform. As a result, in the 2D magnetic configuration, the ion pressure gradient across the sheet width makes a significant contribution (comparable with the Ampere force) to the acceleration of helium ions, whereas in the 3D magnetic configuration, the Ampere force is counterbalanced by the pressure gradient.

Recently for the study of conflict increasingly used method of mathematical optical modeling. Its importance stems from the fact that experimental research such conflicts rather time-consuming and complex. However, existing approaches to the study of conflict do not take into account the stochastic nature of the systems, suffers from conceptual incompleteness. There is a need to develop models, algorithms and principles, in order to assess the conflict, to choose conflict resolution to ensure that not the worst of conditions. For stochastic technological systems as a utility function, we consider the probability of achieving a given objective. We assume that some system S1 is in conflict with the system S2, (SR2R К SR1R), if q(SR1R,SR2R)

The medico-ecological state of Russian regions has been analyzed on the basis of statistical data. It is found that the incidence of different groups of diseases varies significantly in different regions. The regions of Russia are classified according to their medico-ecological parameters; the zones of maximal health risk caused by environmental pollutions, including air, water and soil pollution, are determined. The proposed methods for zoning by health level and the estimate of medico-ecological conditions in different administrative units provide the basis for the development of measures for the adaptation of population. These data can be used for the control of sanitary measures planned by regional organizations for the social–ecological protection of the population.

Results are presented from L-2M stellarator experiments on testing a possible method for detection of water microleakages in the cooling system of the first wall and vacuum chamber of ITER. The method consists in the spectroscopic detection of spectral lines of the OH hydroxyl, which forms via the dissociation of water molecules in plasma. Emission in the spectral band of 305–310 nm can be detected even at water leakage rates less than 10−4 Pa m3/s. Chemical reactions between water and boron compounds on the vacuum chamber wall delay the detection of leakages up to ∼2000 s. A similar phenomenon can be expected when a leakage will occur in ITER, where the materials suggested for the first wall (Be, Li) can also chemically react with water.

The question of creating a computer model designed for the investigation of unsteady mass transfer processes in the dripping of the phospholipid emulsion of sunflower oil in a vacuum cylindrical rotary-film apparatus. The implementation of the mathematical model performance using the finite element method in the Maple.

A mathematical model of data transmission from the site of self-warming in a dispersed system with distributed parameters is suggested which allows one to perform systematic calculations of the parameters of the process of heat propagation in a silo tower. The inverse heat conduction problem is solved allowing one, by using information signals on the current temperature of a granular bed, to promptly guard against the occurrence of local sites of self-warming under conditions of grain storage.

Results are presented from experimental studies of variations in the plasma parameters during the excitation of a multiaxis magnetic configuration by the induction current (up to 17 kA) in the basic magnetic configuration of the L-2M stellarator in the regime of ECR heating at a microwave power of ∼200 kW (∼1 MW m−3) and an average plasma density of (1–2) × 1019 m−3. The current direction was chosen to reduce the net rotational transform (the so-called “negative“ current). The current was high enough for the rotational transform to change its sign inside the plasma column. Computer simulations of the L-2M magnetic structure showed that the surface with a zero rotational transform is topologically unstable and gives rise to magnetic islands, i.e., to a multiaxis magnetic configuration. Magnetic measurements showed that, at negative currents above 10 kA, intense bursts of MHD oscillations with a clearly defined toroidal mode number n = 0 were observed in the frequency range of several kilohertz. Unfortunately, the experimental data are insufficient to draw the final conclusion on the transverse structure of these oscillations. The radial temperature profiles along the stellarator major radius in the equatorial plane were studied. It is found that the electron temperature decreases by a factor of 1.3 in the plasma core (r/a ≤ 0.6) and that the temperature jump is retained near the boundary. A change in turbulent fluctuations of the plasma density during the excitation of a negative current was studied using wave scattering diagnostics. It is found that the probability density function of the increments of fluctuations in the plasma core differs from a Gaussian distribution. The measured distribution is heavy-tailed and broadens in the presence of the current. It is found that the spectrum of turbulent fluctuations and their Doppler shift near the plasma boundary are nonuniform in the radial direction. This may be attributed to the shear of the poloidal velocity. The experimental results indicate that the formation of regions with a zero rotational transform in the plasma core somewhat intensifies plasma transport.

Results are presented from studies of the effect of the discharge parameters (in particular, plasma density and heating power) and the characteristics of the magnetic configuration (e.g., rotational transform) on the confinement of a low-pressure plasma during electron-cyclotron resonance heating in the L-2M stellarator. An analysis shows that the plasma energy in the steady-state phase of a discharge is fairly well described by the product of power functions of the plasma density, heating power, and rotational transform: $$W = W_0 n_e^{\alpha _n } P^{\alpha _p } \iota ^{\alpha _\iota } $$ . The energy scalings constructed in terms of the parameters in the initial stage of free plasma decay and those in the steady-state phase are close to one another. The dynamic analysis of the plasma energy decay is now under way.

Boronization of the vacuum chamber of the L-2M stellarator has resulted in modification of the electron temperature profile. In particular, a well-defined jump in the electron temperature to Te ~ 100 eV in a narrow region Δr/r ~ 0.05 is observed in the temperature profile at the plasma edge. In the present paper, the value and shape of the jump in Te are studied at different values of plasma parameters and ECR heating power. A jump in Te is absent at a power of P ~ 100 kW, whereas at P ~ 200 kW the electron temperature drops from 150 eV to zero within Δr ~ 0.5 cm. The value of threshold power for the formation of a jump in Te at ne ~ 1.7 × 1019 m−3 lies within the range P ~ 100–160 kW. In terms of power per particle this power threshold is P/V/Ne ~ 0.2–0.3 Mw/m3/1019m−3, the value of which coincides with threshold power for ETB formation found recently in the CHS stellarator. When the helical-field strength is 25% or 50% below its standard value, a jump in Te at the plasma edge in L-2M is absent.

A method has been developed for determining the HMF in sulfate cellulose with a photocolorimetric determination of the weight proportion of individual fractions. -- The proposed method can be used for comparative characterization of the amount and degree of polymerization of the HMF in cellulose in plant laboratories.

Ripening of viscose in heating with an industrial-frequency electric current was investigated. It was shown that an effect of homogenization of the viscose is obtained with the electric current. It was found that when viscose was heated with an electric current, in contrast to use of heat exchangers, the minimum viscosity and concentration of gel particles was preserved during the time required for deaeration and filtration. This will allow obtaining a spinning solution with optimum physicochemical properties for spinning.

Under the action of a dc electric current having a voltage of 10–50 V on viscose under steady conditions, heating and electrolysis of the viscose take place; the temperature is increased nonuniformly throughout the volume of the cell: the preheating takes place more intensively in the anode compartment.

The possibility of using an a.c. current of industrial frequency to warm viscose has been investigated. The action of the electrical current on physicochemical indices of the viscose during the process of warming has been studied. The viscosity, ripeness, and degree of esterification of the viscose are practically unchanged during the warming process.

An apparatus has been devised for preheating viscose before deaeration, using an electric current of industrial frequency. The use of this apparatus will make it possible to significantly intensify the viscose heating process, while simultaneously improving viscose quality.