Table of contents

This paper is a preface to the proceedings of the XXXIV International Conference on Interaction of Intense Energy Fluxes with Matter, which was held at the Cheget pension in the village of Terskol, in the settlement of Elbrus, in the Kabardino-Balkar Republic of the Russian Federation, from March 1 to 6, 2019.

All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Information about x-ray terms is necessary to calculate an ionization cross section of atoms or ions by intense energy beam of other particles, also for spectroscopic research method, astrophysical applications. In the paper the simple method is offered to estimate x-ray terms of many-electron atoms and ions. It is based on the atomic number and ionization degree scaling of electron orbital energies. The Dirac–Fock data of some ions of three elements (V, Pd, U) are used to construct the required dependence. One can calculate K and L x-ray terms of ions of the same and other elements using the appropriate polynomial approximations. The inaccuracy does not exceed 8%.

Laser ablation in a liquid (LAL) is an important and perspective way to create nanoparticles (NPs) necessary for modern technologies. LAL is not fully understood. Deep understanding is necessary to optimize processes and decrease high price of the LAL NPs. Today there are two groups of studies: in one of them scientists go from analyzing of bubble dynamics (thus they proceed from the late stages), while in another one, scientists investigate early stages of ablation. In the present paper we consider the process as whole: from ablation and up to formation of a bubble and its inflation. Thus we cover extremely wide range of spatiotemporal scales. We consider a role of absorbed energy and duration of pulse (femtosecond, multi-picosecond, nanosecond). Importance of supercritical states is emphasized. Diffusive atomic and hydrodynamic mixing due to Rayleigh–Taylor instability and their mutual interdependence are described. Liquid near contact with metal is heated by dissipation in strong shock and due to small but finite heat conduction in liquid; metal absorbing laser energy is hot and thus it serves as a heater for liquid. Spatial expansion and cooling of atomically mixed liquid and metal causes condensation of metal into NPs when pressure drops below critical pressure for metal. Development of bubble takes place during the next stages of decrease of pressure below critical parameters for liquid and below ambient pressure in liquid. Thin hot layer of liquid near contact expands in volume to many orders of magnitude filling the inflating bubble.

Laser ablation in liquid (LAL) is important technique, which is used for formation of nanoparticles (NP). The LAL processes cover logarithmically wide range of spatiotemporal scales and are not fully understood. The NP produced by LAL are rather expensive, thus optimization of involved processes is valuable. As the first step to such optimizations more deep understanding is necessary. We employ physical models and computer simulations by thermodynamic, hydrodynamic, and molecular dynamics codes in this direction. Absorbing light metal expanding into transparent solid or liquid dielectrics is considered. We analyze interplay between diffusion, hydrodynamic instability, and decrease of surface tension down to zero value caused by strong heating and compression transferring matter into state of overcritical fluids. The primary NPs appear through condensation during expansion and cooling of diffusion zone or pure gold vapor zone when pressure in these zones drops below critical pressure for a metal.

The most important modern laser technologies include (i) the generation of colloid nanoparticles (NPs), laser ablation into a liquid (LAL—laser ablation in liquid) and (ii) surface hardening of products by laser pinning (LSP—laser shock peening). Significantly, with laser pinning, the surface to be treated is washed with water. Therefore, the physics of processes during ablation into a liquid and during pinning is common. True, the accents are different. If the ablation in the liquid actually forget about the shock wave (SW) generated by the impact, and leaving the thickness of the target, in the problem with pinning, on the contrary, the main question is about the impact. In addition, the role of water in LAL and LSP is different. In LAL, fluid contributes to the formation of NPs and adopts NPs, gently slowing them, whereas in LSP, water is needed to enhance the recoil and increase the amplitude of the hydrocarbon in the product. The complete picture, developed in the work, of course, should include both edges: the formation of ejection into the liquid as a result of ablation, i.e., LAL, and observation of the SW from the nucleation stage to its attenuation in the product volume, i.e., LSP.

The coefficient of the electron–ion energy exchange in liquid aluminum is calculated within the framework of Ziman approach for electron kinetic coefficients. Calculations are made to study dependence of the electron–ion heat transfer coefficient on the electron and ion temperatures.

In this work, the possibility of the implementation of impurities in the compositions of solid thick targets irradiated by intense lasers is discussed in order to solve problems of optically-thick plasma diagnostics. Calculations were conducted for relative intensities of oxygen resonance lines (H-like—3p–1s, 4p–1s, 5p–1s, 6p–1s, 7p–1s transitions) in a recombination quasi-stationary model to obtain plasma parameters. In the experiment with 0.6 ns, 40 J laser pulses focused to 600 μm focal spot at solid polyvinylidene chloride target the parameters of plasma jet stopped by solid oxidized Teflon obstacle were studied by means of spatially-resolved x-ray spectroscopy.

The diffraction method is used to study the properties of laser radiation interacting with a gas-cluster plasma. Based on the simulation of propagation a laser beam with a wavelength 800 nm through a hexagon Cu-mesh and subsequently compared with the obtained experimental diffraction pattern, the contribution of the second harmonic to the laser radiation was considered. The capability of this method to reveal the spectral composition of laser radiation is discussed. Also, the dependence of the visibility of the diffraction pattern on the intensity of the laser beam is considered. Besides, the contribution of x-ray radiation generated from the laser-cluster interaction into the observed diffraction pattern signal was estimated.

Intense electromagnetic fields can be obtained now in THz frequency range. THz pulses with electric field intensity above 1 MV/cm are now requested for strong-field applications like particle acceleration, short electron bunches measurements, controlling the state of the matter. The advantage of a THz pulse in comparison with the visible frequency range is the almost non-oscillating field that interacts with charged particles more efficiently. The advantage over a direct field is the ability to remotely focus this radiation in space and in time. Except for the huge free-electron lasers facilities, the only way to get THz pulses of MV/cm intensity is the conversion of high-power femtosecond laser pulses. We compare two ways of generating intense THz pulses using the radiation of TW and GW laser systems operating at 800 nm. They are two-color filamentation in gas and optical rectification in nonlinear crystals. The prospects for scaling of THz generation methods for a petawatt laser are discussed.

The propagation of short optical and terahertz pulses through a noncentrosymmetric (ferroelectric) film on a centrosymmetric substrate is considered. The effect of terahertz electro-induced second harmonic generation is observed in the film. It is shown that the difference in the group velocities of THz and optical pulses leads to a non-mirror-like dependence of the transient nonlinear-optical response upon a mirror image of the film–substrate structure relative to its surface.

A parallel program has been developed for numerically simulating the interaction of intense laser pulses with many-electron atoms based on non-stationary Kohn–Sham equations. With the use of this program, we calculate the nonlinear electron currents excited during ionization of argon atoms by intense two-color laser pulses. Based on the comparison with the solution of the time-dependent Schrödinger calculations for hydrogen atoms, the importance of taking into account many-electron effects in simulating the generation of secondary radiation in atomic gases under the action of ultrashort laser pulses is shown.

A study of equilibrium radiation in plasma media shows that the spectral energy distribution of such radiation is different from the distribution of Planck equilibrium radiation. Using the quantum electrodynamic approach, a general relation was found for the spectral energy density of equilibrium radiation in a system of charged particles for opaque and transparent media.

One of the strong advantages stated for laser spark plugs is the ability to ignite fuel lean mixtures resulting in improved fuel economy and reduced NO_x emission. However, lean mixtures demand high laser pulse energies for ignition. That could be overcome by using laser ablation rather than optical breakdown plasma to establish the combustion core. For fuel equivalence ratios ϕ ≈ 0.4–1.3, we have experimentally compared ignition thresholds for these two cases at pressures of p ≈ 1–3 bar of a butane-based combustible mixture. Our results show that laser pulse energy for fuel lean mixtures ignition can be significantly (by more than an order of magnitude) reduced using the ablator (stainless steel SS304) as compared to optical breakdown.

The article describes possible experiments with explosively driven non-ideal plasma at the proton microscope at the Facility for Antiprotons and Ion Research. It is proposed to employ linear explosive tubes for plasma generation and to measure an areal density in shock-compressed plasma of argon and xenon. The proposed experiments will provide valuable information on influence of strong interparticle interactions on thermodynamic properties of strongly coupled plasma. The density measurement will help the researchers to understand the nature of wall and wire precursors arising in the shock tubes.

In this work, a perfectly conducting liquid with a free surface, placed in an external uniform electric field, is considered. For a symmetric spatially localized perturbation of the surface, which is directed upwards, it is proved that the part of the potential energy functional which is responsible for nonlinear wave interactions is negatively defined. It is important that this result is obtained without any restrictions on the amplitude of the boundary perturbations, i.e., it takes into account high-order nonlinearities. A general conclusion is that the nonlinearity plays a destabilizing role accelerating the linear instability development of the boundary and defining its explosive character.

The behavior of the free surface of a perfectly conducting liquid in an external uniform electric field is considered in the framework of the Hamiltonian formalism for the case of bounded axisymmetric geometry of the system (the fluid is bounded by a cylindrical rigid wall). Taking into account the influence of quadratic nonlinearities, we derive an amplitude equation which describes the evolution of the boundary. Using this equation, we find the condition for the hard excitation of boundary instability that leads to an explosive growth of surface perturbations. The differences in the description of the dynamics of axisymmetric perturbations of the boundary from the cases of plane, square, and hexagonal symmetries of the problem are discussed.

An experimental method has been developed for optimizing the composition of multilayer radiotransparent structures operating under extreme thermal loads. To optimize the composition of the layers of the radiotransparent radome researchers for the following materials with structures of the glass filler are carried out: glass-fiber laminate (GFR-CM), reinforced quartz material of SiO₂–SiO₂ class (HTRC-CM), organosilicon rubber with a ground mica filler (TCT). The parameters of the heat loads that cause physicochemical transformations in radiotransparent materials and significantly affect the transmission and reflection coefficients of materials, as well as their complex permittivity, are determined. It is shown that the decrease in the transmission coefficient for the construction made of HTRC-CM material is up to 3–4 dB in the frequency range from 2 to 40 GHz, and for constructions made of GFR-CM+TCT is up to 25 dB, respectively. As a result, the radome made of ceramic matrix composite HTRC-CM has the best radiotransparency characteristics.

One of the sewage sludge characteristics is the presence of various pollutant types. This is both pathogenic microflora and chemical pollutants. For example, it is heavy metals. When using the pyrolysis process up to 800 °C with thermal cracking of volatile products, as a method of sewage sludge treatment, in addition to synthesis gas a solid residue is formed. It is about 40% by weight of the initial sewage sludge and has an ash content of 58.2% (on dry state). With this amount of ash, the use of solid residue for energy purposes is not appropriate. Such material is subject to disposal. In this connection, the question arises, what proportion of heavy metals remains in the solid residue and goes into syngas. This paper presents the study results of the effects of pyrolytic processing conditions on the behavior of heavy metals in the composition of sewage sludge. The gross content and solubility in neutral and acidic media of heavy metals in the sewage sludge and the solid residue after pyrolysis are determined. The hazard class according to the content of heavy metals of the sewage sludge and the solid residue is calculated.

Sugarcane bagasse is an abundant waste formed after extraction of sugarcane juice in the sugar-manufacturing process. This large-tonnage waste creates an ecological problem in countries—sugar producers. The study considers bagasse gasification, which is a two-stage pyrolytic conversion into synthesis gas. Raw bagasse and bagasse biocoal obtained by torrefaction and hydrothermal carbonization were used as initial materials. Experimental data are discussed including composition and quantity of gaseous products formed in the process. The results indicated that the process allows obtaining 1.26 m³ of synthesis gas from 1 kg of raw material. Its higher calorific value is 11 MJ/m³.

Development of methods of energy self-sufficiency is a priority for present power generation sector advancing. For our country, it is of particular importance. Approximately 70% of the territory of the Russian Federation (with a population of about 20 million people) are located outside centralized energy supply systems. Capacity of existing centralized energy systems is not enough for many regions of the country. At the same time, in the existing economic conditions, distributed power generation turns out to be more advantageous from an economic point of view in relation to centralized power generation. The production of energy without imported organic fuels implies local fuel and energy resources using, such as peat, wood, agricultural, household and other types of waste. Energy utilization of various types of waste, which are also local fuel and energy resources, will reduce the negative impact on the natural balance of accumulated environmental damage.

In connection with the situation with the environment and energy in the world, it is necessary to study the possibility of using biological waste as an energy resource. The method of thermochemical treatment of organic waste is investigated in this paper. The chicken litter in the form of pellets is used as a raw material. The experimental studies of the torrefaction temperature influence on the thermotechnical characteristics of chicken litter and the yield of products were conducted in lab-scale system. The five temperature regimes of torrefaction (220, 240, 260, 280, and 300 °C) with holding time determined with thermogravimetric analysis are studied. The thermotechnical characteristics of the initial and torrefied material as elemental composition, the lower calorific value, hygroscopicity limit, and bulk density are determined. The properties of non-condensable gases (specific volume yield, chemical composition, and calorific value) are investigated. The material balance for each of the temperature regimes is calculated. The conclusion about the optimum temperature regime for torrefaction of chicken litter based on the results of experimental studies is made.

Hydrothermal carbonization (HTC) and torrefaction are modern low-temperature methods of converting different types of biomass into biocoil. In both processes temperature significantly affects the product distribution and character of solid product. The heating values of HTC biocoil was much higher than torrefacted biochar and 40% higher compared to the initial raw materials (15.68 MJ/kg for raw materials, 22.3 MJ/kg for HTC 210 °C). Biomass has increased carbon content. The maximun one has biochar obtained at 210 °C (55% higher compared to the initial raw materials). The energy densification ratio and energy yield was also higher in HTC process compared to torrefaction process. Hydrochar has less ash that biochar obtained by torrefaction due to washing part of inorganic into the liquid phase.

The shock wave metastable behavior in equilibrium media is detected in numerical experiments. This phenomenon is directly related to the ambiguous representation of a shock wave discontinuity when the shock belongs to the S-shaped fragment of the pressure-velocity Hugoniot. After interaction with weak perturbations the metastable shock wave recovers its original form and parameters (like stable shock). If the amplitude of the perturbations exceeds some critical value, the shock wave instability is developed. The instability is accompanied by formation of the transverse secondary waves switching local post-shock parameters between two Hugoniot segments separated from each other by the absolute instability region. The problem of the metastable shock wave interaction with local entropy perturbation passing through the shock front is studied in the framework of three-dimensional problem formulation. The shock wave transition to the limiting self-oscillating mode is described. Some features of this mode are completely determined by the shape of the Hugoniot and isentropes and does not depend on the shock wave structure. Namely, the shape of the shock front corrugations and flow structure evolution are analyzed. These features may be served as marker of the corresponding thermodynamic anomalies.

Experimental estimates of the process of the ejection of particles and the formation of plasma during the shock wave exits on the free surface of the cooper sample studied were carried out. The radiation intensity was recorded by a three-channel pulsed pyrometer in an experimental assembly with lateral observation. When the impactor speed was about 5 km/s, a stream of particles and plasma flew from the target surface, the front speed of which reached 12.5 km/s.

The paper proposes a method for combining photon Doppler velocimetry and a system of speed interferometers for any reflective systems, which allows one to study the behavior of transparent media under the action of powerful shock waves without the use of additional reflective surfaces. The paper presents the results of an experiment on the propagation of a shock wave in water. In this experiment, water was an absorber; however, the proposed method would also work provided that the test material is transparent and provides reflection.

The report presents a laser diagnostic system designed to analyze the behavior of a matter in extreme states and the propagation of shock waves. The research system consists of a pair of velocity interferometer systems for any reflector (VISAR), push pull and conventional VISARs, forming a vernier scheme. This configuration was designed for Angara-5-1 facility. Test experiments of metal plate acceleration using magnetic field were carried out. The velocities up to 6 km/s were obtained.

In this work, porous media are studied using silicone rubber with glass microspheres as an example. There were investigated three types of silicon rubber samples featuring different concentrations and sizes of microspheres: non-porous silicon rubber, porous silicon rubber with calibrated glass microspheres and porous silicon rubber with glass microspheres having a wide range of sizes. The density of the samples was 0.99, 0.55 and 0.48 g/cm³, accordingly. Investigating spall strength under pulse tension shows that the destruction beginning threshold of the samples in question is quite low. For the non-porous sample, it is around 30 MPa, for the porous ones it is an order of magnitude lower. The spall plate does not come off the sample after the beginning of destruction. The ability of the free surface velocity to change in such a way is typical for materials with a low destruction threshold.

Some results of studies of the processes of elastoplastic deformation in a material with a cubic symmetry of elastic and plastic properties are presented. Cases of shock loading of a cylinder from a single crystal alloy on a rigid target (Taylor test) along three different directions ([111], [001] and [011]) are considered. These directions are characterized by the fact that along them propagation of longitudinal and transverse waves with different speeds is possible. Using the example of solving the Taylor test problem, it is shown that the differences in elastic properties along the [011] directions in cubic crystals determine elastoplastic deformations.

The study of deformation processes in a cylinder made of monocrystalline heat-resistant nickel alloy VZHM8. Different variants of the orientation of the crystallographic axes of a single crystal of a VZhM8 nickel alloy relative to the axis of symmetry of the cylinder when it is shocks an rigid wall (Taylor test) are considered. It is shown that if the [011] direction coincides with the direction of shock loading of the cylinder, the initially circular sections of the cylinder turn into ellipses until the moment of rebound, which is explained by the influence of the negative Poisson's coefficient.

The article analyzes the extent to which the previously detected effect of increase in spall threshold due to nanorelief on the surface can be scaled to large dimensions of the target, the impactor and the relief elements. Earlier, it was shown on the basis of molecular dynamics simulation that the presence of a relief can significantly increase the spall threshold due to plastic deformation in the surface layer of metal and energy dissipation of the reflected shock wave. To study the scalability of this effect on the case of macroscopic targets, and not only on nanoscale systems, an analytical estimation is constructed for decrease in the shock amplitude wave due to plastic dissipation during flattening of cylindrical protrusions on the surface. On the basis of this estimation, it is shown that an increase in the splitting threshold of the rear surface of metals with relief is scalable.

The previously developed mathematical model for macrobody ballistics inside an electrothermal accelerator was modified. The model can be used to predict the projectile velocity for given values of the mass and size of the projectile, the electrodynamic parameters of the capacitive energy storage, and accelerator parameters. The problem of determining the projectile velocity was solved in a hydrodynamic formulation by numerical integration of the equations of motion, the energy conservation equation, and the caloric equation of state. In the case of neglecting the dynamically changing friction coefficient, the calculation results differ considerably from the experimental data, but the model qualitatively describes the physical processes of interior ballistics of the electrothermal accelerator. Electrodes erosion influence was shown.

The main models of the fragmentation of liquid metal droplets in a steam explosion based on thermal stress, shock-acoustic effects and explosive boiling water inside the melt were analyzed. Experimental installations are described and research results are presented. The experiments were carried out with samples of various metals (tin, nickel, zinc, stainless steel), which were heated in levitation mode using an inductor. The maximum temperature for heating a sample of ball-bearing steel did not exceeded 1600 °C. Then, in the molten state, the samples (droplets) fell into a cell filled with distilled water at room temperature. In the experiments, the temperature of the melting sample was monitored and the crushing process was recorded. An experimental material indicating the diversity of the forms of the fragments being formed was obtained. The latter circumstance confirms the assumption of the existence of various fragmentation mechanisms, including the method of breaking drops under the action of intense sound waves caused by the collapse of vapor formations. The results of numerical estimates are given, which indicate that the rate of cooling of particles formed in the process of fragmentation can reach values from 10⁹ to 10¹⁰ K/s. These values are quite sufficient for obtaining various alloys with an amorphous structure. The possibility of destruction of vapor shells around hot drops under the action of pressure pulses caused by the collapse of adjacent vapor-gas formations has been experimentally confirmed.

The material model of iron and steel is developed for fluid dynamics simulations of samples under extreme loading induced by an impact or explosion. The model is validated on a set of plate impact tests using the contact smoothed particles hydrodynamics method. The model takes into account the polymorphic α–ε phase transition in iron which is shown to be correctly reproduced, including the hysteresis effect at unloading. The equation of state for steel is shown to be very close to that of iron on a set of tests with spherical shells under explosive compression; however the yield strength of steel is greater.

The results of experimental investigations of the formation of detonation waves with multipoint initiation for the case of a planar and converging cylindrical wave are presented. A special initiation system was used, where the main element was modeled for manufacturing on a three dimensional printer. A solution was found to form a smooth detonation wave for the planar case. Studies of a converging cylindrical detonation wave have shown the need to solve some fundamental issues related to the nonstationarity of such a wave.

To study the role of individual mechanisms of the flame-front instability, a series of experiments was carried out on the propagation of a spherical flame. Transparent latex shells were filled with pre-prepared hydrogen–air mixture. In various series of experiments, the percentage of hydrogen was varied. The ignition of the flame was produced by a spark discharge with an energy of 1 mJ, a discharger located in the center of the shell. Experimentally, the scattering parameters of the spherical hydrogen–air flame acceleration was found with a constant mixture composition and combustion initiation energy. It was found that at the initial stage of propagation, both acceleration and deceleration of flame front occurs. The parameters of the flame front propagation experimentally obtained are supplemented by calculations carried out using analytical models.

The article presents numerical simulation of the propagation of hydrogen–air flame in adiabatic conditions and with the heat absorbtion on the wall. The results of experiments in a cylindrical shell of 4.5 m³ are compared with the results of numerical simulation. The quantitative agreement between the experimental and numerical results is achieved. It is shown that the numerical model of the combustion with the heat losses under the conditions of the experiment may account the heat losses as an integral effect of the heat absorbtion.

An experimental study of the reaction zone structure and stability of detonation waves was performed for tetranitromethane–methanol (TNM–M) mixture using a velocity interferometer system for any reflector (VISAR). At the near stoichiometric concentration of methanol, it was observed that the amplitude of Von Neumann spike decreases significantly, whereas the detonation parameters increase. The instability of detonation waves in TNM–M mixture was shown, both with respect to one-dimensional longitudinal perturbations and to the curvature of the front leading to the formation of the cellular structure. The dependence of detonation velocity of TNM–M on the diluent concentration and limits of detonation propagation were found.

For the first time, the rate constant of the thermal monomolecular decomposition of n-C₃F₇I in Ar was measured directly using the technique of atomic resonance absorption spectroscopy on a resonant line of iodine atom. Experiments were conducted behind the incident and reflected shock waves in a broad range of thermodynamic parameters (T = 800–1200 K and P = 0.6–8.3 bar). Experimental data were found to conform reasonably to the results of the Rice–Ramsperger–Kassel–Marcus theory master equation modeling based on the results of quantum chemical calculations. The obtained low- and high-pressure limiting rate constants for n-C₃F₇I and CF₃I dissociation in Ar were reported. Third body efficiencies for Kr were also evaluated.

The paper addresses to the experimental investigations of the combustion of test samples of solid fuels based on paraffin and boron-containing compounds and combustion catalysts in the gaseous oxygen subsonic flow. Tests were carried out at the atmospheric pressure and oxygen flow velocity from 27 to 31 m/s. The mass combustion rate of the samples increased by 28% when ammonia borane was added to paraffin, and by 16% when sodium borohydride with a bit of solid oxidizer was added. The biggest amplification of the mass combustion rate using the catalyst reached 5%.

To investigate the features of the processes inside the ramjet subsonic combustion chamber, a numerical model is used. The model is based on Reynolds-averaged Navier–Stokes equations along with turbulence, radiation and combustion models and considers solid fuel pyrolysis. Available in literature experimental data was used to validate the model. The dependences of the heat flow structure on the air flow are obtained. The effect of radiation heat transfer on the regression rate is shown.

In recent years, gas–liquid media are of interest due to their damping properties, which may be sufficient to prevent the mechanical destruction of the oil-filled equipment in consequence of electrical breakdown. For this purpose, an experimental installation was created, where the classical method of electric explosion of a wire is used to study the damping properties of a gas–liquid mixture. Microbubbles with a diameter of 1 mm and 0.5 mm were generated with a tangential air supply in a narrowing part of the Venturi tube or using a Laskin nozzle, respectively. Studies have shown that when the oil is aerated with 1 mm bubbles, final waves amplitude, decreases almost by 5 times, and when gassing with 0.5 mm bubbles the amplitude, decreases by more than 10 times. The attenuation of the amplitude of the pressure wave by a factor of the Euler number e in pure oil occurs in ≈ 7 ms, the bubbles with a diameter of ≈ 1 mm lead to an attenuation in ≈ 5 ms, and the bubbles with diameter of ≈ 0.5 mm in ≈ 2 ms.

In this work, the equation of state for rhenium is proposed as a relationship between pressure, internal energy and density. The consistency of calculation results with experimental data at high energy densities is demonstrated. The equation of state can be used in numerical simulations of dynamic processes in this metal.

From a new point of view, the recombination of two-dimensional electrons enclosed in a MgZnO/ZnO heterojunction with localized holes in the valence band is considered. It is suggested to consider quasi-holes in the two-dimensional electron system as quasiparticles in the Wigner crystal. The quasiparticles corresponding to electrons removed from the Wigner crystal are vacancions. Because of quantum tunneling effect, they are not localized. The vacancion energies E(k) form a band of width D which is proportional to the vacancy tunneling probability. The width D corresponds to the photoluminescence band of the two-dimensional electron system. The shape of the photoluminescence band of the Wigner crystal is considered within the tight-binding approximation for dispersion E(k) and compared with the experimental results.

In this work, results of quantum molecular dynamics calculations of thermodynamical properties of uranium are presented. The experiments on shock compression and subsequent isentropic expansion of porous samples of uranium are well described. Our first-principle calculations of the shock Hugoniot and release isentropes of uranium demonstrate good agreement with experimental measurements. In addition, unique information of temperature along experimental curves was obtained including supposed entries of isentropes into the two-phase liquid–gas region according to the hypothetical kinks on the experimental isentropes.

The state-of-the-art density functional theory (DFT) methods provide high quality data about materials properties at extremes. The cost for this is the days of modern supercomputers operation to obtain a set of particular points on a phase diagram. Moreover, the low density region is usually unreachable for these methods due to convergence issues. We demonstrate that an adequate wide-range model of electron subsystem may be constructed using the simple Thomas–Fermi approach corrected by introducing semiclassical bound states instead of continuous ones. The obtained thermodynamic properties are compared to Saha and Kohn–Sham DFT data with good agreement thus covering the region between low and normal densities of hot plasma.

A direct transformation of the sintered BC₃ phase to a novel diamond-like d-BC₃ phase was observed in a diamond anvil cell (DAC) at high temperature, 2500 K and high pressure, 22 GPa. For heating a specimen in a DAC a laser heating (LH) system combined with an acousto-optical filter and synchronized with a video camera was used. Combining the LH system with the acousto-optical filter allows measurement of the temperature distribution under infrared (1064 nm) LH of a specimen under high pressure in a DAC. The starting material with a composition BC₃ was obtained by sintering a powder of nanodiamonds with a powder of boron microparticles at 6.0 GPa during 150 s heating at 1200 °C. The quenched BC₃ specimen was studied by the Raman spectroscopy.

On the basis of the additive approximation model, a formula for determining the van der Waals constant was obtained and the possibility of correctly describing the long-range part of the interaction potential of solidified inert gases crystals was indicated. Using the modified Lennard-Jones potential and experimental data on the dissociation energy and the equilibrium radius, the dispersion constants of systems of inert gas pairs and an alkali metal–inert gas are determined. The results of the calculations are in general agreement with the experiment.

The warm dense hydrogen is studied by the ab initio molecular dynamics in the region of the fluid–fluid phase transition. A method for calculating the properties such as concentration and lifetime of H₂ molecules is developed. As warm dense hydrogen passes the transition, the concentration of H₂ molecules decreases smoothly, while the lifetime changes abruptly by several orders.

The molecular dynamics methods for calculation of shear viscosity based on liquid diffusivity are tested against the classical Green–Kubo relation for n-pentane at 330 K and 0.601 g/cm³. The D-based method is shown to be as accurate as calculation of viscosity from the Green–Kubo formalism for pentane liquid. Stokes–Einstein relation is also in agreement with simulation results. However, it has much bigger uncertainty. The results of the simulation are in agreement with experimental data.

The role of segregation of chemical elements upon free surfaces in the peculiarities of the plastic deformation mechanisms of thin films of the high-entropy CoCrFeMnNi alloy was clarified using a combined simulation of the Metropolis Monte Carlo and molecular dynamics. Irrespectively of surface orientation and stoichiometric composition of alloy Mn escapes to free surface and Fe goes to the bulk of the films. Ni also enriches the (111) surface while Co content is reduced. It is shown that for different compositions segregation reduces or decreases the elastic limit of the samples. In Co₁₀Cr₁₀Fe₃₀Mn₃₀Ni₂₀ for all considered free surfaces, segregation equally influences the type and volume fraction of the formed defects. In Co₃₀Cr₃₀Fe₁₀Mn₁₀Ni₂₀, they may remain the same or the mechanism of plastic deformation may change drastically in samples with segregation depending on the orientation of the free surface. Despite the redistribution of the volume fractions of various type defects, in general, the main mechanism for the development of plasticity in samples both before and after segregation is the growth of the hcp-bands. Change of defect structure in samples with surface segregation compared to samples with random distribution of elements is not necessary related to change of elastic limit.

In this work, the interaction of the moving edge dislocation with obstacles in form of copper atoms is studied using the molecular dynamics simulations. The samples are aluminum monocrystals of 52 × 60 × 15 nm³ with axes oriented along directions [110], [111], [112]. The structure of copper solid solution is reproduced with following procedure: aluminum atoms are randomly selected and replaced by copper atoms. The concentration of copper atoms varies from 0.25% to 1%. The dislocation movement occurs under action of shear deformation. It is found that zones with a low concentration of copper atoms only slow down dislocation in an aluminum matrix, and the zones with a high local concentration of copper atoms not only produces stronger resistance to dislocation movement, but also they cause the change in the slip plane of the dislocation segment. When a significant part of a dislocation line moves to a neighboring slip plane, the complete transition of the dislocation to this slip plane can occur. It is also noted that such transitions of dislocation segments from one slip plane to another are accompanied by the formation of vacancies. Also the maximum value of the shear stress σ_xy is estimated-its value is approximately 250 MPa.

The effect of high pressure on the Seebeck coefficient and temperature dependences of the electrical resistance of single-wall and double-walled carbon nanotubes was studied in order to detect phase transformations occurring in carbon nanotubes in the pressure range 4–46 GPa. Diamond anvil cells with conductive synthetic diamonds were used to create high pressures. We observed a number of features associated with the structure changes of nanotubes. Temperature dependences of the electrical resistance of single and double-walled carbon nanotubes have the form characteristic of nondegenerate semiconductors. Analysis of results indicates the destruction of the structure of carbon nanotubes at high pressure.

Adhesion energy is an important characteristic of interfacial interactions. Usually one apply notion of adhesion energy to solid–solid interfaces, but it also could be extended to gas–solid and liquid–solid interfaces. In later case phenomenon of adsorption is closely related to the adhesion energy. In this work we apply molecular dynamics method to calculate the specific adhesion energy for gas and liquid ethane on a graphite substrate. Influence of temperature and density on the value of the specific adhesion energy is investigated. Langmuir adsorption model is applied to interpret results and establish connection between notions of adsorption heat and specific adhesion energy. Appearance of multilayer adsorption is detected for higher densities. Developed model and numerical approach to calculate adhesion energy and surface coverage can be applied for different types of the adsorbate and the substrate.

Molecular dynamic (MD) modeling revealed that takes place swing up of transverse vibrations of graphene atoms with their transition to bending vibrations of membrane type. The amplitudes of such oscillations can reach large values, which considerably exceed the interatomic distances already for samples of micron sizes and amount to 10⁻² from the length of the sample. The results of MD simulation were compared with the characteristic vibrational frequencies of graphene in the approximation of the tensioned membrane. The behavior of the graphene membrane during it loading with a liquid metal microdroplet has been considered also. Contact angles and relative stretching of the membrane outside and under the drop allow us to calculate the surface tension of the drop.

We present the first experimental demonstration of a new imaging system for in-situ measurement the two-dimensional distribution of the effective emissivity and temperature of a heated specimen. In this work, we use the model of a gray body, assuming that the emissivity is constant over the entire wavelength range from 600 to 800 nm. Data acquisition was done using the laser heating (LH) system developed at the STC UI RAS. The LH system allows us to reach extremely high temperatures up to 6000 K at high pressures. The main component of the system is an imaging tandem acousto-optical tunable filter synchronized with a video camera. The maximal error of the emissivity measurement of the tungsten sample was found to be 13%, whereas the maximal error of the temperature measurements did not exceed 2%. An influence of different factors on the error of the emissivity determination is also discussed.

The experiments were carried out upon a research facility comprising three current generators. One of them was used to initiate the explosion of a foil and the other two, X-pinch backlighting sources were used for diagnostics. In the experiments, an upper limit has been determined for the decay time of the metastable state of a superheated metal. For aluminum, at a foil thickness of 6 μm and a deposited energy of 5.3 ± 0.5 kJ/g, the metastable state decay time was about 90 ns; for copper, at the same foil thickness and a deposited energy of 2.1 ± 0.3 kJ/g, it was about 250 ns; for nickel at the same foil thickness and a deposited energy of 1.3 ± 0.4 kJ/g, it was about 390 ns.

Experimental devices and techniques for determining surface and interface tensions microdroplets of low-melting metals bordering with vacuum, liquid mediums and solid substrates have been described. Dynamic method is discussed for the gallium microliter sessile droplet immersed in water and a static method is considered for the tin microdroplet pending on a conical tip of a cantilever needle.

Some thermodynamic functions are considered in the work. They have a scaling form and connected with thermodynamic properties at the saturation line (the fluid density (ρ_l), the gas density (ρ_g), the order parameter, the mean diameter of the coexistence curve, etc). We have paid attention to well-known experimental (ρ_l, ρ_g, T) data of C₆F₆, which are got in a wide temperature interval. One more object is investigated in the work. It is a height dependence of the density, ρ(h), in the critical region, here h is the distance of the gamma-ray beam from the bottom of the cell, in which the sample is placed. These (ρ, h, T) data are got at the earth gravity (g = 9.8 m/s²). In our work, it is studied a behavior of the sample at a special condition: the gravitational effect is reduced in the cell with the sample. In the case of the microgravity, we have elaborated an equation, which expresses a meniscus position in two-phase sample in the critical region. Combined models are elaborated to approximate (ρ_l, ρ_g, T) data of C₆F₆ in the wide temperature interval including the critical region. These models meet the scaling theory of critical phenomena.

This paper presents the results of the experimental studies of filtration modes of gas-condensate fluid using a binary mixture of methane–n-butane. It is shown that there is a possibility to obtain both the normal two-phase filtration mode and the self-oscillatory mode depending on the filtration conditions and the composition of the model mixture.

The finite element method is used for simulation of productivity in dynamic Taylor tests. Two different approaches for prediction of plastic deformation of finite element method is employed for numerical simulation of yielding under dynamic impact Taylor tests. Obtained results of modeling are compared with experimental ones. These are Johnson–Cook model and von Mises yielding criterion enhanced by incubation time approach. The simulation results have shown that the simplest method based on von Mises plasticity model provides good coincidence with experimental profiles of specimen shape in the course of deformation. The shortcoming is that the correct value of yield stress is depending on the loading rate and should be known beforehand. Thus, if there was a method to predict the value of dynamic yield stress to be used within von Mises criterion then this simple approach could be the optimal choice for simulation of dynamic plasticity in conditions of Taylor test.

The bifurcation transitions from the symmetric to asymmetric flow regimes in shear thinning fluids in a channel with sudden contraction and expansion were studied by means of numerical simulations. On the example of the Carreau–Yasuda model, the bifurcation diagrams of shear thinning fluids with different viscosity flow curves were revealed along the critical Reynolds numbers of the bifurcation transitions. It was found that increase in variations of viscosity with shear rate leads to a noticeable decrease in critical Reynolds number and increase in dimensions of the angular vortices as compared to Newtonian fluids. The obtained results indicate the enhancement of flow instability of shear thinning fluids in channels with the variable cross-sections.

Numerical modeling was used to study the patterns of droplet deformation in two-phase Newtonian fluids flowing through a three-dimensional rectangular microchannel with a sharp narrowing. The elongation of single droplets of different viscosities was investigated in different channel zones. Calculations were carried out for different confinement parameter—the ratio of droplet diameter to the gap thickness. The increase in this parameter was shown to lead to the substantial increase in the droplet relative elongation. The effect of coalescence to microfiber formation in flowing emulsion was considered.

The dynamic behavior of two-phase Newtonian fluid in co-flow coaxial capillaries was studied numerically. It was found that morphology of the dispersed phase is uniquely described by three non-dimensional parameters as capillary numbers and ratio of Reynolds numbers of the fluid components.

The numerical simulation of the first stage of fiber-spinning process was performed. The single-mode Giesekus model was used for polymer fiber stress calculations. Fiber profiles, longitudinal velocity, tensile stress and apparent elongational viscosity were analyzed depending on the stretch speed and the degree of anisotropy of the polymer.

We present analytical and numerical description of two-phase flows in a porous medium for one-dimensional case. This research is aimed at modeling of natural gas condensate flows at hydrocarbon reservoir conditions. The model is component-scalable, uses generalized cubic equation of state and assumes equal pressures in coexisting phases. It can be used for miscible and immiscible fluid in a unified way. First results for binary mixture flows of alkanes are provided including self-oscillatory regime.

In the paper, we present implementation and benchmarking for gas dynamic solver for hypersonic flow problems with fully implicit scheme. The aim of the paper is to verify and measure efficiency of the implicit method for computational architecture based on multiple graphics processing units. The verification is performed on a flow over the sphere-cone problem. We consider hypersonic flow regimes of Mach number around 20–30. New results are cross-compared with results of the previous version of the code for explicit time marching scheme.

We present the results of calculations of electron and ion diffusion by the method of molecular dynamics in an ultracold multiply charged plasma. The calculations were carried out in a wide range of Coulomb coupling parameter. The problems of similarity for a Coulomb multiply charged plasma are discussed. It is shown that in a multiply charged classical plasma for the diffusion coefficients in a wide range of coupling parameter, the similarity assumption is valid.

Influence of a weak electric field on the coherent Rydberg resonances was studied on two-photon transitions 2S–nD by recording the resonance fluorescence of lithium atoms in a magneto-optical trap. It was observed that an isolated spectral line 2P–nD transferred to the spectral band width growing with a principal number n (or an electric field E). It was shown that the frequency tuning of a resonant radiation on the left (right) edge of the band allows to create a gas of Rydberg atoms with fixed and large dipole moments d ∝ ea₀n² (e is the elementary charge, a₀ is the Bohr radius), oriented against (along) the electric field. The radiation frequency was tuned on the center of the band would produced atomic states with zero dipole moments, but with a big contribution of states with maximum angular momentum quantum number l ~ n.

Energy loss of a proton propagating through a low-temperature gas of magnetized electrons is studied by molecular dynamics method for the case when proton velocity is much more than electrons thermal velocity. Strong uniform magnetic field is considered when electron Larmor radius is much smaller than distance of closest approach (Coulomb radius). High electron density, and hence small values of the Coulomb logarithm, is considered. The dependence of energy loss on angle between the proton velocity and the magnetic field direction is studied. Results of calculations are compared to Derbenev and Skrinskii theoretical approach to average friction force.

An analysis of the response of a dense plasma to electromagnetic waves of moderate intensity can be used as a tool to study the validity of physical models describing the behavior of matter in extreme conditions. Within this work, the new experimental data are presented on oblique incidence of polarized electromagnetic wave. The study of polarized reflectivity properties of nonideal xenon plasma was accomplished using laser light at ν_las = 2.83 × 10¹⁴ s⁻¹. The measurements of polarized reflectivity coefficients of explosively driven dense plasmas have been carried out at incident angles up to θ = 70° for plasma density ρ = 1.8 g/cm³. The simple model of the ionization kinetics of the plasma transition region is considered.

Three-component electroneutral systems of finite-size classical macroions with two different charge numbers Z₁ ≫ 1 and Z₂ ≫ 1 and point-like oppositely charged microions are analyzed. Free energy of a mixture of two sorts of macroions is estimated within the Wigner–Seitz cells approximation. The non-linear screening effect is taken into account via the Poisson–Boltzmann approximation within the both cells. The equality of microions pressures at the boundary between the co-existing cells with the different sorts of macroions is used as an equilibrium condition. The difference between the total Helmholtz free energy in equilibrium is shown in comparison with the situation when the Wigner–Seitz cells with macroions with the different charges have the same volumes.

We study dust vortices called dust devils and dynamics of dust in this structures. Dust devils are well formed relatively short-lived vortices that can appear over well heated surfaces like deserts and are clearly visible due to large amount of dust raised. Dust particles rotating in a flow bump and scrape each other and as a result particles obtain electric charges. Space separation of particles with opposite charges leads to generation of macroscopic electric field. We simulate dust dynamics with taking into account the electric field of the vortex.

A self-consistent model for the formation and evolution of dusty plasmas in the Martian ionosphere is developed. The effects of the initial distributions of dust particles, as well as condensation and absorption of carbon dioxide and water molecules by dust particles, are studied. Theory values of characteristic sizes of dust grains and their charges are obtained. The theoretical values of the sizes are in agreement with the data of observations. The possibility of the formation of dusty plasma structures in the Martian ionosphere which are analogous to noctilucent clouds in the atmosphere of the Earth is discussed.

Based on the analysis of the dusty-acoustic soliton properties, a simple technique for estimating the Debye radius is proposed. It is shown that the Debye radius is approximately equal to 1–1/3 of the width of the soliton density profile, which can be easily determined from the analysis of photographs of a dust cloud.

The results of the analysis of the mean square displacement and the trajectories of moving polymer particles with a modified surface in a dusty plasma monolayer under the influence of laser radiation are presented. It has been revealed that the dynamics of particle motion in a monolayer consists of three modes: finite motion within confinement, Brownian motion, and combined directional chaotic motion. The results of the analysis of linear displacement along and across the direction of motion of dust particles at various values of the laser radiation power are presented too. It has been shown experimentally that polymer particles with a modified surface are active Brownian particles and their activity grows with increasing laser radiation power.

We present the results of the analysis of the trajectories, dynamic entropy, and root-mean-square displacement of moving copper particles in a cluster of chain structures when exposed to laser radiation. We have revealed that the dynamics of the particle motion in the cluster corresponds to three modes: motion in a localized area, Brownian motion, and combined directional chaotic motion. The results of the analysis of linear displacement along and across the direction of motion of dust particles at various values of the laser radiation power are presented. It has been shown experimentally that copper particles are active Brownian particles and their activity grows with increasing laser radiation power, leading to a structural phase transition with the exchange of chain fragments within the cluster.

Recent studies of dusty plasma structures formed by polydispersed CeO₂ particles in a dc glow discharge at a temperature T > 1.6 K were shown to be the first experiments on dusty plasma in an exotic dark glow discharge mode. The properties of cryogenic helium plasmas at T ~ 1 K are summarized and discussed.

A system of like charges interacting with a weak repulsive Yukawa potential and confined in a one-dimensional parabolic electrostatic trap is under consideration. It is shown that inter-particle distance in this system grows from the center of the structure to its periphery. The same effect takes place for the mean square displacement of particles from their equilibrium positions, which corresponds to the amplitude of thermal oscillations, and for the value of Lindemann parameter. This leads to different degrees of order for particles located at different distances from the center of the structure. This result might be important for the study of phase transitions in dusty, colloidal and one-component plasmas.

The effect of cloud density on the grain charging is of great importance in complex plasma physics. The quasi-neutrality condition brings about changing of ratio of a spatially averaged ion density to electron density in the dust cloud. Strong interaction between ions and highly charged grain complicates the analysis of the effect of ion density increasing on ion flux on the grain. The theoretical approach to ion flux correction on the grain space charge by the use of effective ion density instead of spatially averaged density is discussed. The experimental measurements of charges of solitary grains and the grains in the cloud under similar plasma parameters are used to prove the proposed approach.

The nonlinear features of the vibrational motion of a single dust particle trapped in a standing strip are investigated. The excitation of the nonlinear oscillations with the large amplitude of the order of 1.5 mm is due to the periodic movement of the standing striation caused by the square-wave modulation of the discharge current. The frequency responses are investigated depending on value of the modulation depth. The anharmonic effects of the dust particle oscillations such as parametric instabilities and hysteresis are obtained. The theory of the anharmonic oscillator provides a good quantitative description of the experimental data. The values of the thresholds of excitation of parametric instabilities, the anharmonic coefficients and the critical values of the oscillation amplitude for the hysteresis are calculated. The potential energy curve of the single dust particle trapped in the striation is calculated using the values of anharmonic coefficients.

The article presents the previously obtained results of the modification of spherical microparticles of melamine-formaldehyde injected as a dust component of complex plasma formed in stratified glow discharge in neon. Particular attention is paid to changing the particle size depending on the residence time in the plasma. A mechanism is proposed for heating particles by ion flow sustaining a stable charge of their surface. Calculations of the heat balance are presented, confirming the results obtained in the experiment.

The onset of magnetic field on the glow discharge results in the redistribution of plasma flows, which in turn may cause the change of the charge of dust particles levitating in strata. Upon that dusty structure changes its geometric form and inner ordering of particles. In this work, we present the investigation of the influence of magnetic field on dusty structures formed in striation of glow discharge. We detected the variation of geometrical dimensions of structures with magnetic field, and the behavior of interparticle distance was determined. There was obtained the dependence of the concentration of dust particles in normal to vector B cross section of structure on the magnetic induction. Corresponding graph was compared to one of rotation speed, which has three characteristic diapasons. First one is characterized by negative projection of angular velocity Ω on B, two other diapasons are characterized by positive Ω projection and the slope of Ω(B) graph.

Comparison of discharge channel temperature in gaseous hydrogen of high density with current amplitude of ~ 1 MA at initial gas pressure of 5–7 MPa, determined by two methods, was done under stage of its maximal contraction. In the first case determination of the temperature value of 72–73 eV was made by intensity of soft x-ray radiation from the channel for experiments with current amplitude of 1.1–1.5 MA. The estimation of the temperature on the basis of the data received by magnetic probe method and specified electric characteristics of the channel was of ≈ 140 eV for experiment with initial gas pressure of 5 MPa at current amplitude of 0.93 MA. The temperature determination by the last procedure has small accuracy caused by the limitation of the magnetic probe technique in determination of the channel contraction ratio and some assumptions for near-electrode voltage drops calculations by this way. Apparently, the channel temperature in stage of maximal contraction is of ~ 100 eV.

This article presents the study of the influence of the cathode material of a plasma injector on the parameters of the x-ray source of a point Z-pinch (PZ-pinch). The experiments were carried out on the compact pulse power radiograph PR-PZP-M1 (210 kA, 220 ns). The new type of the plasma injector based on a ceramic insulator and a composite cathode is developed and tested in the experiments. PZ-pinches based on tin, silver and gold were studied. It was shown that tin is the most applicable material to the PZ-pinch formation in terms of radiography. The PZ-pinch mass optimization has been carried out to obtain the brightest x-ray source with minimum sizes. The achieved x-ray source diameter is 12 ± 3 μm, height is 18 ± 5 μm in the spectral range hν = 1–3 keV.

The results of modeling in the framework of magnetic hydrodynamics (MHD) for the development of a plasma jet in Z-pinches are presented. It has been shown that plasma jet origin is associated with the development of MHD instability m = 0, but not with the conical current sheath structure. MHD modeling is also carried out for θ-pinch systems where generation of plasma jets is much less effective. The corresponding analysis is presented.

Development of plasma jets (PJ) generated in plasma focus machine is investigated numerically by the snow-plough model. It is shown that axial speed of PJ, V = 5 × 10⁷ cm/s, few times exceeds the speed of thermal plasma expansion. It means that long distance transportation of plasma jets can be achieved. Results of calculations are in good agreement with experimental data obtained by interferometry.

The paper deals with the results of the study of the plasma energy loss in a chamber of the three phase alternating current arc plasma torch at pressures above atmospheric. It is shown that the loss due to radiation takes the main share. A time-averaged estimation of the radiation power per unit length of the arcs and its dependence on pressure was obtained based on the results of calorimetric measurements of the heat flux into the end part of the plasma torch. The dependence of the fraction of energy loss by radiation versus the total loss in the plasma torch chamber depending on the pressure and gas flow rate are presented. The dependence of the efficiency of the plasma torch versus the gas flow rate and pressure is also given. Studies were conducted on a plasma torch over the power range from 50 to 200 kW. The working gas was nitrogen.

The plasma linear multicusp (PLM) device was constructed to test materials by powerful plasma loads. The facility is a linear magnetic trap with an 8-pole multicusp magnetic plasma confinement. In the PLM, the electron temperature of the hot and cold fraction is of 50 and 10 eV, the electron density—2 × 10¹⁸ m⁻³, the stationary plasma confinement is up to 200 min and more, which is an advantage for testing materials of the divertor and first wall of a fusion reactor. Tungsten, molybdenum, graphite, iron were tested in stationary helium discharges in the PLM with the thermal load more than 1 MW/m². The temperature of the tested plates reached 1000 °C and more. A stochastic nanostructured surface and fuzz-like structure with fibers of less than 50 nm in a diameter were observed on the surfaces irradiated by hot plasma.

Explosive-magnetic generators (EMGs) unlike capacitive storages (CSs), as a rule, have growing power. The effective operation of pulsed plasma loads, such as pulsed plasma accelerators (PPAs), plasma foci, plasma breakers, etc, can be provided at realization of the mentioned advantage of EMG as a power source. A technique of laboratory experiments with PPA is presented in this paper. The experiments with PPA powered by CS precede the explosive experiment with EMG. The dependencies of the load operation modes on the start parameters are determined by the analysis of the experimental data. They included the dynamics of the inductance and the position of the current shell inside the PPA. The technique allows reducing the number of expensive explosive experiments and supplements the database of nonlinear dependencies of the load parameters under various amplitudes of the current pulse that is important for mathematical modeling. The technique based on experiments together with the estimations allowed solving the problem of matching of non-linear loads type PPA with EMG. Thus, the productivity of experiments with EMG increases greatly. The developed technique can be adapted to a wide class of nonlinear loads.

In the present work, the experimental results of reaction of morphological indicators (sprout and root length, number of roots, 3-day germination) of seedlings of high quality winter wheat seeds treated by plasma byproducts in the three-electrode system of surface dielectric barrier discharge with dc bias on the third electrode in humid air of atmospheric pressure at different polarity of the bias voltage are shown. The treatment was carried out for 15 min in a strip electrode system (eight 1 mm width strips with 4 mm distance between them, a sinusoidal voltage of 2.7 kV (rms) with a frequency 23 kHz) made on a corundum ceramic barrier (1 mm thickness) with the additional third electrode which is a stainless steel grid distant 10 mm from the surface of the dielectric barrier. Direct-current bias of 8 kV of positive or negative polarity was applied to the third electrode. Seeds were located on the surface of the third electrode. The treatment was also carried out with vibration of the system (the imitation of seeds movement along the third electrode). It is shown that the efficiency of treatment depends on the month of carrying it out. It was succeeded to get a reliable stimulation with weak control. With strong control (potential sowing months) it was not obtained. The imposing of dc bias in any considered case is less efficient than plasma products affection without bias. The vibration of electrode system leads to seeds damage during the treatment and notable germination reduction.

Dynamics of the discharge with a liquid cathode was studied using the method of high-speed visualization. The video data was compared with the emission spectra of the discharge plasma. Electrical parameters of the discharge were measured. The effect of organic impurities in the solution on the discharge parameters was investigated.

A cold atmospheric-pressure plasma jet was studied using the novel microwave plasmatron recently developed. Cold plasma jet was generated in Ar flow by electrode 2.45 GHz discharge of up to 200 W power in the portable plasmatron burner (torch) with 2.5 cm diameter outlet. Oscillograms and floating potential dependences on distance from the torch outlet were measured by planar electric probe. Axial and radial distributions of gas temperature in a cold plasma jet were obtained by means of thermocouple method.