Table of contents

This paper is a preface to the proceedings of the XXXV International Conference on Equations of State for 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, 2020.

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

• Type of peer review: Single-blind

• Conference submission management system: ELBRUS 2020 conference submission management system, http://www.ihed.ras.ru/elbrus20/contribution/

• Number of submissions received: 84

• Number of submissions sent for review: 84

• Number of submissions accepted: 65

• Acceptance Rate (Number of Submissions Accepted / Number of Submissions Received X 100): 77.38

• Average number of reviews per paper: 3.60

• Total number of reviewers involved: 44

• Any additional info on review process: Each submitted manuscript was first reviewed by the editor and in case of a gross violation of the guidelines, it was returned to the author for revision. After initial approval by the editor, the article was sent to the reviewer. The reviewer evaluated the article, provided comments. The author made corrections, or argued against criticism. Some articles were transferred for consideration to another reviewer (as a rule, if the first reviewer refused to give a final positive or negative assessment of the article). If approved by the reviewer, each article was evaluated and accepted by the editor.

• Contact person for queries: Konstantin V. Khishchenko, Joint Institute for High Temperatures of the Russian Academy of Sciences, konst@ihed.ras.ru

An equation of state for vanadium is proposed over a wide range of densities and pressures in the form of an analytic function of pressure on the specific volume and internal energy. The calculated cold curve and shock adiabat are compared with the available data from static and dynamic compression experiments. The developed equation of state can be used to simulate physical processes in vanadium under conditions of high energy density.

Experimental data on electronic binding energies in a ground state of lanthanides are analyzed. Internal individual shells K, L, M, N are studied in detail. The data scatter is discussed. Atomic number similarity law of orbital binding energies is shown and deviations from it in some experimental results are treated as measurement errors. Polynomial interpolation of patterns makes it possible to restore missing and correct erroneous data. Comparison is made with experimental data from other sources and theoretical results.

Computing-experimental method of verification of operability of composite porous package for protection of thin-walled constructions from non-stationary one-sided loadings is proposed. A set of explosive devices for generate loads of the required space-time distributions is described. Two new explosive devices for generation of low-pulse loads of microsecond duration with low difference in loading time at the surface of the tested composite constructions are considered. Time deformation profiles of glass-plastic cylindrical shell under low-impulse load of microsecond duration are given. It is received that use of wire or foil sensors for measurement of deformations give close results when the shell stage of deformation of glass-plastic thin-walled constructions is investigated.

We examine the dependence of the Gibbs free energy and entropy on pressure and density along MgO isotherm 300 K. Some theoretical works have previously predicted a drastic drop of entropy along MgO isotherms by analyzing existing experimental data and extrapolating them to high pressures. We present first-principle calculations of thermodynamic properties of MgO under pressure using density functional theory and quasi-harmonic approximation. The robustness of our calculations is verified by comparing the calculated and experimental phonon dispersion curves. The comparison with available diamond anvil cell experimental data is also provided. Our estimate for the B1–B2 phase transition is in good agreement with other experimental and theoretical studies. However, our results for entropy along isotherm 300 K do not agree with previous theoretical estimates based upon the integration of thermal expansion coefficient and isothermal bulk modulus by volume.

Equations of state for the CaSiO₃ phases are constructed using a thermodynamic model based on the Helmholtz free energy. The proposed thermodynamic formalism is allowed us to calculate the full set of thermodynamic properties of minerals in a wide range of temperatures and pressures. The proposed equations of state are constructed with a small number of fitting parameters and reliably represent the properties of studied minerals under T–P or T–V parameters.

Under atmospheric pressure conditions, direct polymorphic transitions α to β, β to γ and reverse γ to α were studied, as well as certain phase equilibrium points for 1,1-diamino-2,2-dinitroethylene (DADNE) were determined in the temperature range from 145 to 475 K. The anisotropic characteristics of the thermal deformation of DADNE crystals are determined by powder thermal x-ray diffraction of an internal standard. The points of structural changes were recorded in increments of 20, 10, and 2 K. The calculations of x-ray powder diffraction data were carried out using full-profile analysis methods with the integrated cycle of molecular modeling of the structure of molecules integrated into the algorithm.

Experimental study of thermal expansion of chromium by millisecond pulse heating technique was performed. The results obtained allow calculating the density of Cr in the wide range of high temperatures up to the melting point.

Zirconium carbide ZrC produced from nano-sized powders is a new material; its properties have not, in fact, been studied. We present the experimental results on the electrical resistivity of the zirconium carbide within the temperature range of 1200–2500 K. The ZrC specimens were prepared by spark plasma sintering from nano-size particles at a temperature of 2100 K. The goal of the present work is to compare the obtained results of the electrical resistivity with data for ZrC produced by traditional methods.

A method for calculation of the thermodynamic properties of diatomic ideal gases using interatomic interaction potentials is discussed. For instance the computation of thermodynamic functions such as heat capacity, entropy and reduced Gibbs energy in the temperature range 298.15–10 000 K is shown for diatomic argon compounds.

Crown ethers are unique compounds with exceptional ion binding properties. We investigate the 18-crown-6 ether molecule binding selectivity for a set of alkali ions (K⁺, Rb⁺, Cs⁺). We employ combination of umbrella sampling technique with the weighted histogram analysis method to derive free energies of ion–ether association. The obtained results are in a good agreement with experimental values available and represent the ion selectivity feature of the 18-crown-6 ether.

We study single crystal zirconia using molecular dynamics method. We calculate the diffusion coefficient of oxygen ions in the temperature range from the occurrence of diffusion at our calculation parameters to the loss of stability of the crystal. In the potential of interatomic interactions, in addition to conventional terms, we introduce into our model the interaction due to the polarization of atoms. These interactions turned out to be crucial for the correspondence between the calculations and available experimental data.

When processing experimental data with systems such as velocity interferometer system for any reflector (VISAR), periodic measurement uncertainty arises. The appearance of its uncertainty is investigated and computer modeling of signal processing with random noise is carried out. Analytical dependences of the error value on the signal-to-noise ratio and signal phase are obtained. Methods of reducing this error are considered.

The behavior of perturbed shocks belonging to Hugoniot segments with ambiguous representation of the shock-wave discontinuity is considered. The segments are adjacent to the region of the shock wave instability L > 1 + 2M from the side of greater and lower pressure. Here, L is the D'yakov parameter and M is the post-shock Mach number. The model equation of state is used. For the constructed Hugoniot curve, the ambiguity sections are overlapped by the shock wave neutral stability regions. The three-dimensional simulations with varying post-shock parameters and perturbation intensity are performed. It is shown that shock waves considered are metastable: for any intensity of the shock wave, there are intervals of the perturbation threshold values inside of which the shock is neutrally stable or unstable. Neutral stability is characterized by the weak damping of secondary waves occurring as result of the perturbation.

This article suggests profiling the surface of one of the welded plates in a special way during explosion welding. The principle and method of calculating the profile of the plate based on the materials and welding speeds of the plates are given. It is assumed that such profiling of the surface of the plate will allow to obtain more durable welded joints and even perform welding at a speed below the minimum collision speed for welding plates with smooth surfaces. As an example, a full calculation of plate profiling for specific collision parameters of welded plates is given.

The paper discuss the electrical conductivity in detonating benzotrifuroxan. The obtained data demonstrate that the primary carbon condensation takes less than several nanoseconds time.

This paper presents the results of experiments carried out to reveal the influence of the initial parameters of the thermite mixture Al–CuO on the signs of a chemical reaction between its components. Initial parameters were the characteristics of the starting components, preparation conditions and characteristics of the mixture and samples, experimental schemes, methods of initiation. The most important parameter was the preliminary mechanical activation of mixture. The prepared mixture with controlled porosity was placed in experimental assemblies and a chemical reaction was initiated. Values and tendencies of the brightness temperature and the propagation rate of reaction area were determined for different initial parameters of mixture and initiation conditions. The reaction in the volume of the experimental assembly goes into flare combustion in open space. Values of brightness temperature at the stage of flare formation have a stochastic character, determined by the random distribution of reaction sites in the initial volume of the components. A high-speed camera, a pyrometer, photoelectronic and electrocontact sensors were used as diagnostic tools. The final goal of the study is to optimize parameters of mechanical activation of mixture for its effective applying in various conditions.

The combustion wave propagation in Al–CuO and Al–Bi₂O₃ termite mixtures was experimentally investigated. Waveforms of electric current through the reaction area between electrodes with a given potential difference, chronograms of piezo- and photodiode response, the data of pyrometric measurements, as well as photos of the glowing area were obtained and analyzed. There were revealed the advance filtration of the gas component through pores of mixture, the generation of charges providing considerable electrical conductivity of chemical reaction products, the connection of electrical conductivity dynamics with the optical radiation of the chemical conversion region.

The paper presents the results of large-scale experimental and simulation study of the propagation of premixed near the lower flammability limit hydrogen–air spherical flame. Experiments were carried out in a cylindrical volume of 4.5 m³ covered with thin polyethylene film. The effect of buoyancy and stability of the flame ball in the unconfined volume are studied experimentally and numerically. Numerical analysis of the problem shows that the flame ball becomes unstable after some period of stable propagation that qualitatively corresponds with experimental results. The effect of chemistry in a flame ball propagation process is studied numerically. A comparison of experimental results and numerical simulations are presented. A comparison of numerical simulations with and without chemistry is shown. The subject and results of the study are of critical importance for the industrial explosion safety and hydrogen safety of nuclear power plants.

In this paper, the results of investigation on detonation properties of heterogeneous mixtures of ceramic proppants with slurry liquid explosives (LE) such as nitromethane (NM) plus ammonium perchlorate compositions are presented. The mixtures discussed are promised to be used for far field fracture stimulation of oil bearing formation subjected to hydraulic fracturing. Experimental results on detonation velocities of LE-proppant mixtures in long tubes up to 25 diameters versus internal diameters are presented. Results of experimental comparison of detonability of LE studied with pure NM in proppant matrix are also represented. The objective of the study was to assess detonability and detonation parameters of these mixtures at various initial conditions.

The two-step chain reaction of methane combustion in air is integrated into the FlowVision software package. The conical flame numerical simulation under normal conditions using the built-in single-step chemical reaction was performed. A comparative analysis of the numerical results for one- and two-step schemes, as well as experimental results was made.

Based on data on shield volcanoes of Venus and the distribution of craters on Mars and sea basins on the Moon, the flux density of galactic comets in the Orion–Cygnus branch was calculated. The comets flux density is 5 × 10⁻¹⁰ year⁻¹ km⁻². This value was used to estimate the number, energy and fallings frequency of galactic comets on terrestrial planets in the period from ≈ 5 to 1 million years ago. The article shows, that the falls of such comets can explain the phenomena of "newest uplifts of Earth's crust" and "young volcanism" on Earth, the appearance of shield volcanoes on Venus, the asymmetric structure of Mars, as well as origin of large craters, seas and mascons on the Moon, Mars and Mercury. A hypothesis of formation on the Moon of the South Pole–Aitken basin by galactic comets is proposed.

Multilayer products made of ultra-thin layers are widely used in modern science and technology. Laser exposure is used as one of the promising methods of processing such products. In this regard, we study the ablation of a layered target. A physical model is constructed, numerical simulation is performed, and experiments are carried out. The experiments were conducted with two different lasers and various diameters of the focal spot. To estimate the absorbed energy the reflection coefficient was measured. The results of calculations and experiments are consistent with an accuracy of about 10%. This allowed us to refine the model of two-temperature states and determine the strength of nickel. It is explained why, with an increase in the absorbed fluence, first the upper layer breaks in the multilayer.

Laser exposure at a sufficient intensity creates a shock wave (SW), propagating in the irradiated target. The process is used in many technological applications. As a result of femtosecond exposure, a warmed up layer with a thickness of d_T ∼ 0.1 μm occurs. The radius of the heating spot R_L varies from values of the order of a micron (focusing on the diffraction limit) up to tens or hundreds of microns depending on the experiment. As you can see, R_L ≫ d_T, therefore one-dimensional motion with a plane surface is generated. The quasi-plane SW stage ends when the SW moves away from the target surface to a depth of about R_L. Then the stage of quasi-hemispherical propagation begins. The paper analyzes the transition from plane to hemispherical SW. The motion of the "wings" of a hemispherical wave on the target surface bordering on a gas or vacuum is investigated. Theoretical estimates and numerical simulation results are presented. Analysis of the movement of the "wings" on the surface is important for experimental diagnostics of phenomena inside the target.

Elastic-plastic transformations together with or separately of polymorphic phase transitions are important for the theory of shock waves. Here we discuss changing a classification consisting from elastic, split elastic-plastic, and pure plastic shocks. The split shocks means that there are two jumps: the elastic precursor and plastic shock, and that the elastic jump is independent relative to plastic one. In the split regime the precursor moves with elastic speed of sound overrunning the plastic jump and going further and further ahead relative to plastic jump as time proceeds and becoming weaker and weaker. We oppose the split shock to the one-wave (1W) two zones (elastic and plastic—2Z) shock (1W2Z shock). The 1W2Z wave propagates as whole (therefore one-wave), the plastic shock dynamically supports the elastic one, and the average distance between the jumps does not change in time. The powerful elastic shocks (their amplitudes are much higher than are usually suggested for elastic shocks) were found in experiments with femtosecond laser pulses and confirmed in large scale molecular dynamics (MD) simulations. The observation of the 1W2Z shocks is another important finding coming from MD. The report is devoted to lasers, shocks, and applications. In the second part of the report the generation and propagation of the shocks created for laser shock peening by lasers with ultrashort or nanosecond pulses are considered.

Analytical expressions for the electron thermal conductivity of nickel and aluminum are presented. The thermal conductivity depends on the electronic and ionic temperatures, density and phase of the substance (solid or liquid). The expressions obtained can be used in hydrodynamic calculations of the ablation of these metals or multilayer targets made from them. We consider the case when ablation is caused by the action of ultrashort laser pulses.

In the present article, using the methods of mathematical modeling, the thermal conductivity of silicon was obtained in a wide temperature range (0.3 ≼ T ≼ 3 kK), including the region of semiconductor-metal phase transformations. As it is known, there are two mechanisms of heat transfer in a solid: elastic lattice vibrations and free electrons, therefore, in the study of the thermal conductivity of silicon, the lattice and electronic components were taken into account. The lattice (phonon) thermal conductivity in this work was determined within the framework of the atomistic approach. The Stillinger–Weber and Kumagai–Izumi–Hara–Sakai interaction potentials were used for modeling. The results of the comparison of the phonon thermal conductivity obtained from the simulation results with the used interaction potentials are presented. The modeling of the thermal conductivity of the electronic subsystem of silicon with intrinsic conductivity in this work is based on the use of the quantum statistics of the electron gas using the Fermi–Dirac integrals. The total thermal conductivity of silicon, obtained as the sum of the electronic and phonon components, is compared with the experimental data.

An x-ray radiography technique based upon phase contrast imaging using a lithium fluoride detector has been demonstrated for goals of high energy density physics experiments. Based on the simulation of propagation an x-ray free-electron laser beam through a test-object, the visibility of phase-contrast image depending on an object-detector distance was investigated. Additionally, the metrological capabilities of a lithium fluoride crystal as a detector were demonstrated.

Study of warm dense matter remains a very important task for understanding of many unique phenomena observing as in astrophysical research as in inertial fusion and fast ignition. In this work, we studied the parameters of plasma created by 1.7 ps laser pulses of relativistic intensity of 7 × 10¹⁸ W/cm² in a specially designed Al–Cu wire-shape target, in comparison with a flat Cu and Al foil targets. We observed the strong emission of neutral or virtually neutral Cu K_α line from both Cu foil and Cu wire part of targets, which indicates the creation of a dense state exposed to the intense flow of hot electrons. Parameters of the plasma were evaluated by comparison of experimental spectra with the results of modeling by collisional-radiative kinetic code PrismSpec under the plasma zone approach. The using of Al foil in front of Cu wire part of target allowed avoiding the direct heating of Cu-wire and acquiring spectra of Cu K-shell emission evidently belonging to emission of warm dense matter (WDM) state. The upper estimate for the electron temperature in WDM region was found to be below 80 eV.

Over the past two decades, LIH SB RAS and BINP SB RAS have jointly conducted experiments on time-resolved (TR) small-angle x-ray scattering (SAXS) with detonating high explosives. The purpose of these experiments is to restore the dynamics of carbon species condensation to diamond nanoparticles by analyzing series of SAXS patterns behind the detonation front measured in real time with fast detectors. This knowledge is crucial for the development of reliable detonation models. In this paper, we compare SAXS patterns of identical nanodiamond samples measured at the TR-SAXS extreme state of matter end-station (BINP SB RAS) in the static mode under realistic conditions simulating fast real-time measurements with polychromatic SR beam and traditional SAXS BioMUR beamline at the Kurchatov Synchrotron Radiation Source (NRC "Kurchatov Institute") with monochromatic synchrotron radiation (SR) beam. These experiments confirm that the size of scattering inhomogeneities determined in dynamic experiments with single bunch exposure with polychromatic SR beam is correct.

Terahertz (THz) waves can influence a diverse spectrum of cellular processes. In the present study, we focus on the effect of high-power broadband THz pulses on cell culture. An experimental setup for long-term irradiation of cells with THz pulses with intensities of about 32 GW/cm² has been developed. Human skin fibroblasts were exposed to THz pulses with a field strength of about 3.5 MV/cm for 90 min. Preliminary results on the THz-induced apoptosis process in cells are presented.

Laser ignition has been studied in powerful four-stroke engines, not only because of the fast payback, but also because of the more convenient diagnostics in a large scale setup. High-performance compact engines have not been studied, even though advantages of laser ignition could be much more pronounced for those because of harmful emission reduction and multi-fuel abilities. Compact piston engines are considered as an alternative for fuel elements and batteries for portable, automotive and unmanned aerial vehicles. These are characterized by a small combustion chamber comparable to the spark plug inter-electrode gap in axial direction, and its low ratio to bore size. However, for Wankel engines this problem exists at any scale. Laser ignition of lean fuel mixtures in such engines could significantly improve performance by reduced fuel consumption, thermal loads, and a cleaner exhaust. We have investigated the possibility of laser ignition in rotary-piston (Wankel) sub-kW scale model engine using different kinds of fuel mixtures: hydrogen, methane, propane, butane, gasoline, and ethanol based. A custom built compact diode-pumped solid state laser has been used to substitute the original glow plug, respectively. Laser ignition has been found possible and quite beneficial for both types of engines and different fuel mixtures; in terms of NO_x emission reduction especially.

The heat conduction of an aqueous solution of polypropylene glycol in the region of stable and unstable states was studied by the method of pulse isothermal impact on a substance with a characteristic time of 100 ms. It has been shown that the short-term superheating of a homogeneous solution not only above the liquid-liquid equilibrium temperature (low critical solution temperature), but also above the diffusion spinodal is fundamentally possible. The negative character of the deviation of the heat conduction of a solution from the additive law calculated from the heat conduction of the pure components at a given temperature was revealed. The signs of manifestation of spinodal decomposition accompanied by a significant intensification of heat transfer were found.

This work is devoted to the study of thermalization of plasma created by head-on collisions of high-energy plasma flows in a longitudinal magnetic field of 0.5–2 T. Hydrodynamic flows contained the energy of 200 kJ with velocities from 2 × 10⁷ to 4 × 10⁷ cm/s and ion density from 2 × 10¹⁵ to 4 × 10¹⁵ cm⁻³ were created inside the 2MK-200 facility by two electrodynamic plasma accelerators equipped by a system of pulsed gas injection. Nitrogen, neon and their mixtures with hydrogen and deuterium were implemented as working gases. A process of plasma creating was investigated by near-wall magnetic probes situated in different parts of the interaction chamber. Temporal evolution of the plasma electron temperature had been traced by x-ray photodiodes covered by different filters. It was discovered that the plasma electron temperature changed insignificantly during 6–8 μs after it reached the maximum value, which means that it ionization state can be considered as quasi-stationary.

Using data of the Baksan Underground Scintillation Telescope we have searched for muon neutrinos and antineutrinos with energies above 1 GeV coinciding with the gravitational wave (GW) event GW170817 that was recorded on August 17, 2017, by the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) and Advanced Virgo observatories. This is the first detection of the new type of events occurring as a result of a merger of two neutron stars in a binary system. A short gamma-ray burst (GRB) GRB170817A accompanying this event is evidence of particle acceleration in the source whose precise position was determined by detection of the subsequent optical signal. No neutrino signals were found with the Baksan Underground Scintillation Telescope in the interval ±500 s around the moment of the gravitational wave event GW170817, as well as during the next 14 days. The upper limits on integral fluxes of muon neutrino and antineutrino from the source are derived.

We investigate non-standard interactions of neutrinos with atomic nuclei through excitations of leptoquarks. A leptoquark term in the Lagrangian admits the possibility that neutrinos interact with gluons. The current lower limits on the leptoquark masses are of the order of 1 TeV depending on the leptoquark quantum numbers and couplings. Such heavy states can be produced in ultra-high energy cosmic neutrino scattering processes. The four-momentum transfer squared and the Bjorken variable simultaneously probed in these processes may reach values kinematically inaccessible at present collider experiments. We study the impact of the gluon density in a nucleus on the cross section for the neutrino-induced leptoquark production. We show that taking into account the nuclear parton distributions shifts the production threshold to significantly lower neutrino energies. As a particular case we consider the interaction with oxygen, which is abundant in water targets used in neutrino detection experiments.

Resonance excitation of the ⁸³Kr first nuclear level (E = 9.4 keV) by solar axions formed via the Primakoff mechanism and via an M1-transition in the ⁸³Kr nucleus in the Sun is searched. The γ-and x-ray photons and the conversion and Auger electrons arising from the excited-level relaxation are detected with a proportional counter in the underground low-background facility of Baksan Neutrino Observatory. The following experimental constraint is obtained for the product of the axion-photon coupling constant and the axion mass: |g_Aγm_A| ≼ 6.16 × 10⁻¹⁷. In the framework of the hadronic-axion model, this corresponds to a new axion-mass constraint of m_A ≼ 12.6 eV at 95% coincidence level (C.L.). In case of pure hadronic interaction the upper limit for axion-nucleon coupling is $|{g}_{\rm{AN}}^{3}-{g}_{\rm{AN}}^{0}|$ ≼ 8.3 × 10⁻⁷ at 95% C.L., which corresponds to upper limit for hadrionic axion mass: m_A ≼ 64 eV at 95% C.L. with the generally accepted values S = 0.5 and z = 0.56.

At the Baksan Neutrino Observatory (Institute for Nuclear Research of the Russian Academy of Sciences, Moscow) deployed in the Caucasus mountains, it is proposed to create, at a depth corresponding to about 4700 mwe (meter water equivalent), a large-volume neutrino detector on the basis of a liquid scintillator with a target mass of 10 kt. This article describes the current state of the first stage of the project, namely a prototype detector with a scintillator mass of 0.5 t. The design of the detector, the equipment and methods used are described.

The Carpet-3 air shower array is being built at the Baksan Neutrino Observatory, which is located near Mount Elbrus (North Caucasus) at an altitude of 1700 m above sea level. The main aim of the experiment is gamma-ray astronomy in the energy range above 100 TeV to search for diffuse gamma radiation and sources and to study the generation mechanisms of this radiation. The paper provides an overview of the current state of the experiment, as well as its prospects.

Biomass is known to be an alternative source of energy due to its availability and less environmental impacts in comparison with fossil fuels. Widespread of biomass allows us to solve the problems associated with development of local energy production. The developed at the Joint Institute for High Temperatures of the Russian Academy of Sciences technology for biomass energy utilization let to reduce energy consumption. It is achieved through the use of energy released during exothermic reactions, which is accompanied by heating of various types of biomass, which, as it follows from the literature, is realized for the first time in the processes of gas fuel producing. The second energy-saving factor of the developed technology is that the heat source is the gas piston power unit (GPU) combustion products. In this case, a cogeneration scheme is implemented. The results of experiments on the biomass conversion in GPU combustion products medium and numerical calculations in a one-dimensional non-stationary approximation are presented. The method of biomass thermal conversion under development will make it possible to obtain gas fuel or energy supply systems at local fuel and energy resources.

Black holes (BHs) are three-dimensional (3D) singularity-free macroscopic defects in the superfluid-crystal-like four-dimensional (4D) periodic waveguided multiverse (PWM) concept by the author, like edge-dislocations in 3D smectic-A liquid crystals. The PWM-co-emergent intrinsically identical ordinary matter (OM), antimatter (AM), dark matter (DM), dark antimatter (DAM) arise in the nearest 3D-waveguids–3D-universes with the co-emergent special relativity, weak Newtonian gravity, the expanded equivalence principle–the expanded general relativity (PWM-GR) foundation, predicting gravity mass symmetry–matter-antimatter antigravity. The PWM-BHs have identical Schwarzschild radii, outer gravity potentials as the GR-BHs, but flat-singularity-free gravity potentials inside. Microscopic PWM-fermions—singularity-free defects-holes in the weightless superfluid PWM-vacuum-medium–form singularity-free, intrinsically physically identical macroscopic defects: OM-BHs, DM-BHs, AM-BHs, DAM-BHs in the nearest 3D-waveguides. The smallest free PWM-BHs have 4.3 solar masses (excluding microscopic Hawking's GR-BHs never experimentally detected), they are stable—too heavy for gravitational Schwinger-like virtual electron-positron pairs decoupling—unable emit gravitationally repulsive virtual positrons; they also unable emit repulsive PWM-antiphotons, electrostatically confined in the gravitationally polarized PWM-vacuum, preserving its decay, holding the fundamental baryon number conservation law, prohibiting Hawking's-GR-BHs evaporation. Only plasma-eating, growing PWM-BHs emit thermal positrons, simultaneously absorbing attractive virtual particles. The dominating PWM-DM-pulsars explain relativistic galactic positrons flows excess over electrons.

The problem of seismic protection from the main types of surface acoustic waves and shear–pressure (SP) evanescent waves emanating from vicinity of an epicenter of an earthquake is discussed. Herein, SP waves represent a kind of the evanescent waves arising at critical angles of incident of bulk shear waves. The proposed seismic protection method utilizes vertical trenches (vertical barriers) filled with the specially constructed granular metamaterials. Some of nonlinear hyperelastic models along with nonlinear and inelastic models are analyzed for applications using granular metamaterials in case of cyclic dynamic loadings that correspond to arrival of the large intensity surface acoustic and evanescent waves. The main attention is paid to arrival of the large intensity Rayleigh, Rayleigh–Lamb and SP waves, as the most frequent waves and the most dangerous waves for engineering structures. Some of the new constitutive equations for metamaterials exhibiting different elastic moduli at tension and compression phases are proposed and discussed.

In this paper, a numerical scheme for solving the equations of the dynamics of a compressible fluid, based on the Runge–Kutta discontinuous Galerkin (RKDG) method and an adaptively refined cubic mesh (AMR), is applied to the problems of shock interaction with solid and liquid obstacles. Features of effective implementation algorithm for the graphic processors (GPU) are described. Several well-known validation test problems are considered. Results of full detailed three-dimensional simulations of the shock with the gas or fluid bubble using the developed GPU–RKDG–AMR solver are presented.

We report on development of the wave packet molecular dynamics (WPMD) with density functional theory (DFT) simulation technique that we proposed earlier for nonideal plasma and warm dense matter simulations. The method is based on the WPMD where the electron exchange-correlation effects are taken into account using the DFT approach. It is aimed at studying simultaneous dynamics of electrons and ions in equilibrium and non-equilibrium conditions for a wide range of temperatures and densities. Compared to classical molecular dynamics and WPMD simulations the method of WPMD-DFT provides more accurate representation of quantum effects such as electron–ion coupling and electron degeneracy. At this stage of the method development we pay a special attention to the performance issues such as acceleration with graphical processing units, the choice of an optimal simulation box size with respect to the boundary conditions, the use of an adaptive mesh for calculation of the exchange-correlation energy, and implementation of our algorithm in the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS). The results for internal energy of equilibrium dense hydrogen plasma are presented for evaluation of the method.

Understanding mechanism of the soot formation process is important for reduction of harmful emissions from combustion and also for synthesis of carbon nanostructures. However, at the moment, both the mechanisms of carbon cluster formation and its morphology are poorly understood. In this paper, we present the results of molecular dynamics simulation of the formation and growth of carbon clusters formed at high temperatures from polyaromatic hydrocarbons.

The results of calculating the distribution function of the ion-microscopic field at the neutral point of ultracold plasma by the method of molecular dynamics are presented. The calculations are carried out for the model of two-component fully ionized ultracold plasma in a wide range of the Coulomb coupling parameter values. To evaluate the accuracy of the calculations, the distribution function of the ion microscopic field of randomly distributed charged particles was calculated and compared with the exact Holtsmark function. Results obtained for our model can be used for any equilibrium or non-equilibrium strongly coupled plasmas, in which quantum effects are negligible. Comparison with results of other authors is made.

We have developed far-off resonance single beam dipole trap for optically cooled lithium-7 atoms. In the present paper we discuss some preliminary results. In order to improve performance of the trap we optimized the trapping time and increased the atoms number. The lifetime was increased by improving the vacuum from ≈ 3 × 10⁻¹⁰ Torr to ≈ 10⁻¹¹ Torr and preparing all the atoms in the selected atomic state (the lower ground state level). After vacuum improvement the single particle losses in the magneto-optical trap was reduced by 100 times and as the result the lifetime in the dipole trap reached 25 s.

Plasma screening can enhance the thermonuclear reaction rates significantly. The most pronounced effect takes place in the white dwarf cores and neutron star envelopes; there the enhancement factor can reach as tenths orders of magnitude. Here thermodynamically consistent description of this effect, which does not violate of the detailed balance principle, is discussed.

New results of measurements of s- and p-polarized reflectivity of nonideal plasma at the frequency of the external electromagnetic field ν_las = 2.83 × 10¹⁴ s⁻¹, free-electron number density n_e = 3.3 × 10²¹ cm⁻³ (Coulomb nonideal plasma parameter Γ = 1.2) and n_e = 5.2 × 10²¹ cm⁻³ (Γ = 1.4) are presented. These data are the result of the next stage of study of optics of a warm dense matter. We present a microscopic approach to describe the entire set of experimental data on the optics of strongly correlated plasma.

We discuss the mechanism of the influence of the multiply-charged colloidal clusters on linear electric transport in diluted polyelectrolytes. The structure of these colloids has well known form. They are effectively neutral and cannot participate in the transfer of charges in the solution. Nevertheless, there is a linear increase in the conductivity of colloidal polyelectrolyte with an increase in the density of colloids. This phenomenon is observed experimentally. It is shown that this happens due to the change of electric field in the polyelectrolyte under the effect of colloidal particle polarization.

The dusty plasmas on the Moon are investigating through the direct detection of the dust particle fluxes on the lunar surface and through the measurements of the parameters of ambient plasma. The PmL instrument is the first device developed both to detect dust particles and to determine the characteristics of the plasma environment. The PmL instrument mounted on future Russian lunar missions Luna-25 and Luna-27 is described in the article. The suggested landing sites of the stations are situated nearby the Boguslavsky crater (nearby 70° south latitude of Moon). The values of the lunar surface potential, Debye length and electric field at a latitude of 70° were obtained in this paper. The distribution of the dust particles near the selected latitudes was also determined. A brief description of the methods for detecting the dusty plasma parameters near the lunar surface was suggested.

Processes associated with the presence of magnetic fields, which can be important in dusty plasmas on the Moon, are considered. Lower-hybrid wave processes under interaction of the magnetotail of the Earth with dusty plasma near the surface of the Moon are described. Lower-hybrid waves are excited due to the relative motion of magnetospheric ions and charged dust grains, which leads to the establishment of a well developed lower hybrid plasma turbulence. The effective collision frequency characterizing the anomalous loss of ion momentum due to ion-wave interaction, as well as the electric fields arising in the system are found. It is shown that the electric fields excited due to the development of lower-hybrid turbulence are somewhat weaker than those arising due to the charging of the lunar surface under the action of solar radiation. Nevertheless, they are quite significant to affect the electric field pattern above the Moon. The obtained effective collision frequencies should be taken into account when deriving hydrodynamic equations for dusty plasma ions with allowance for their turbulent heating. Problems related to the consideration of magnetic fields, which can be important for detailed study of the dusty plasmas at the Moon, are stated. The possibility of generation of wave motions in the near-surface lunar plasma should be taken into consideration when interpreting the observational data.

The article discusses dusty plasmas processes in the Earth's ionosphere associated with the passages of meteoroids and the spread of the meteor tail. Mechanisms explaining the occurrence of electrophonic noises recorded simultaneously with the passage of meteor bodies are suggested for extremely low frequencies range. It is explained by modulational instability of electromagnetic waves from meteor associated with the dust acoustic mode with characteristic frequencies 0.03–60 Hz. As electromagnetic waves propagate in the dusty plasmas of the meteor tail or in the dusty ionospheric plasmas, dust acoustic waves are excited as a result of the development of modulational instability of electromagnetic waves at characteristic frequencies and as a result, the electromagnetic waves become modulated. At the surface, these perturbations can be converted into sound waves by means of receivers. The growth rates of modulational instability at which the modulational excitation of extremely low-frequency dust acoustic disturbances occur are calculated. The conditions of the development of modulational instability are given. The correlation between observations of ionospheric radio noises and passages of meteors is noticed. Observed data of electrophonic noises include discussing range of frequencies 0.03–60 Hz.

A study of a dust trap in a glow discharge in highly non-uniform magnetic field is carried out. The trap is near the end of the solenoid on the side of the anode part of the discharge; it exists only in the magnetic field and it is resistant to its change. In the trap a volume dust structure is formed and comes into rotation with angular velocity of about 10 rad/s depending on the conditions. The interpretation of the reasons of rotation of the dust structure in the detected dust trap is given. Four physical processes known from literature are considered; numerical estimates are made. A feature of the dust trap being studied is a highly non-uniform magnetic field in which the discharge current channel expands and its radial component appears. Ampere force action due to radial component of current and longitudinal component of magnetic field is taken as the reason of dust structure rotation. The numerical estimate for the average section gives the value from 2.5 to 10 rad/s depending on the assumption of the radial component of the current.

When investigating the dusty plasmas in a magnetic field, there are a number of problems in creating stable dust structures. This is particularly evident in stratified discharge at fields above 1000 G. This report discusses the conditions of the experiment under which for the first time it was possible to create the stable dust structure in the glow discharge with fields up to 10 000 G. The areas of stability and instability of the dust trap have been detected depending on discharge parameters such as a gas sort, a pressure, a current and a radius of discharge tube. The conditions of instability are compared with the literary data on the properties of the glow discharge in plasma. The general recommendations for the creation of the stable dust structure are concluded.

In order to understand in detail the physical processes in the dusty plasma in the magnetic field in the stratified discharge, we carried out an experiment to observe the geometry of the glow of standing strata in the neon discharge. Stratified discharge was video recorded in longitudinal magnetic field inside magnetic coil at values of magnetic induction from 0 to 2700 G. As the magnetic field increased, both the configuration of the striation and the intensity of their glow changed. Video recording was carried out by a periscope video camera with the possibility of displaying an image on a computer. The results show a tendency to merge the strata; the head of the striation is lengthened. The suggested interpretation shows the decrease in the longitudinal gradient of the electron temperature, which leads to the decrease in the electron eddy current in the striation and the slight decrease in the rotational velocity of the dust structure.

The present work is devoted to the investigation of the melting line of the body centered cubic Yukawa crystal. Two different methods were applied: numerical integration of the Clapeyron–Clausius equation by Kofke algorithm and study of a equilibrium two-phase system, containing the both liquid and crystal phases. The values of the widely used in practice empirical phase transition criteria were calculated on the melting line. During the melting and crystallization the density of the Yukawa ensemble changes abruptly, which makes it impossible to obtain the self-similar solution of the equations of motion of the particles. As a result, using of a couple of dimensionless parameters lead to errors when calculating the melting line. However results of this paper show that these errors are comparable with the density change, which is less than 3% in the selected range of parameters.

Gas temperature fields in the air corona discharge with a plane comb electrode system have been determined for the negative and positive polarities of the applied voltage. Highly sensitive schlieren technique used in the study allowed detecting a temperature change in tenths of a degree centigrade at room temperature of the gas flow. The obtained results suggest that the gas in the studied electrode system does not undergo heating at the given range of working parameters.

A dependence of total near electrode voltage drops for high-current high-pressure discharges versus current rise rate into discharge in a range of 10⁹–10¹² A/s at initial gas pressure up to 200 MPa is presented. A new technique for the near-electrode voltage drops determination is proposed at conditions of the fast energy input. The technique is based on measuring the characteristics of a shock wave detaching from the discharge channel. Total near electrode voltage drops were increased with the current rise rates from around two hundreds to approximately ten thousand volts.

In this work, the behavior of cathodes made from pure tungsten and pure hafnium in the direct current electric arc at 200 A and in atmospheric pressured argon medium was investigated. The research was focused on the processes happening with the cathodes during the arc initiation phase (first 100 ms after the power input). The processes of rapid cathode destruction were registered, and can be characterized as the destruction of the cathode in liquid phase due to electro-magnetic forces. Characteristic times of the whole process were recorded, as well as the changes in temperature fields on the cathodes surfaces and the rate of mass loss for both types of cathodes. It has been shown that the initial destruction of the cathode plays a major role in the cathodes resource life.

A low-temperature plasma generator of a mixture of nitrogen and propane has been developed, with the possibility of supplying propane to the cathode region, to the arc burning zone, and also to the plasma stream below the arc binding zone. The maximum propane flow rate for a given plasmatron design and plasma-forming nitrogen flow rate, at which the arc is stable, was determined. When propane is supplied into the arc binding zone, the decay products are deposited mainly on the electrodes, and when it's supplied to the anode after the arc binding, the decomposition products are deposited mainly at the anode exit. The study of the microstructure and analysis of the phase composition of the decomposition products of propane were performed.

The analysis of the current state of the technological process and equipment for plasma coating of various powder materials has been carried out. To increase the processing efficiency during the deposition of ceramic materials and refractory alloys a novel technological scheme of plasma spraying with a powder feed axially to the cathode was proposed and preliminarily tested. Basing the plasma torch with an expanding channel of the output electrode its plasma-spraying version has been developed in which the sprayed powder was supplied both to the cathode or anode arc striking zone and to the current-free plasma jet. The electrophysical parameters of the argon plasma torch and the speed, size and temperature of particles of sprayed powder were investigated. It was shown that the particle velocity of Al₂O₃ powder depending on the gas flow and arc current reaches up to 100 m/s. The temperature of the powder particles in the vicinity of substrate at a current of 300 A approximately equals to 2400–2500 K.

Based upon the results of a literature review, a set of physical parameters suitable for quantitative comparison in experimental and numerical studies is determined. The review showed the feasibility of modeling the process of the outflow of an immersed jet of inert gas into the surrounding space and the evolution of a free shear layer formed by hot and cold gases to analyze the process of convective and diffusion transport of various types of particles. In the model formulation we consider the problem of solid destruction by a melt of the same substance, as well as by a nitrogen stream at high temperature. The test simulation of the problems of two-phase interaction of a immersed jet of molten liquid and hot gas, on the whole, qualitatively showed the reproduction of the main characteristics of the flow: the generation of large-scale vortices around the jet in the induction zone, the oscillations of the jet when it collides with an obstacle, and the shape of the cavity formed.

With the aim of studying nitrogen plasma flow impacting graphite surfaces, we investigated the evolution of a plasma jet moving from the nozzle of the plasma torch to the target. The motion is accompanied by a decrease in temperature from 10 to 7 kK with a loss of ≈ 60% of the deposited energy and an increase in the density of carbon-containing impurities with partial preservation of the local thermodynamic equilibrium. The main reactions are thermal processes of the formation and decomposition of molecules, dissociative recombination and recharging of nitrogen ions. In the presence of carbon impurities, this set is supplemented with the substitution reaction C + N₂ ↔ CN + N, electron-collision processes of stepwise ionization and recombination, and a whole ion-molecular cascades of reloads and substitutions. It has been established that a small admixture of carbon (∼ 0.1%) manifests itself only in ion-molecular kinetics, increasing the electron concentration, determining the ionic composition of the plasma, and thereby violating the equilibrium between its neutral and charged components. This leads, in particular, to the recombination nonequilibrium distribution of carbon atoms over electronic states. Other carbon-containing impurities (CN and C₂) are not significant.

In this work, the experimental results of surface barrier discharge plasma products affection to winter rye seed germination at the initial stage of growth and seedling tolerance to low temperatures are shown. The treatment was carried out for 10, 60, and 180 s in the plane-parallel electrode system with sinusoidal voltage of 2.7 kV with frequency 4.4 kHz applied to the strip electrodes at a distance of 5 mm from each other. It is shown that the treatment has no effect on seed germinating ability. In 180 s exposure treatment mode the stimulation of 3-day seedling shoot and root system length occurs. The freeze tolerance response of two-stage cold hardened seedlings grown from treated seeds shows that both the exposure of seed and the freezing temperature affect on the formation of positive response.

This research is devoted to the possibilities of using lithium-ion (Li-ion) batteries operation in engine cold start systems. Down-scale test specimen of LiC₆–LiNiMnCo (NMC) and LiC₆–LiFePO₄ batteries coupled with supercapacitor module were tested in cold cranking mode. The charge currents between Li-ion battery and supercapacitor module are experimentally determined. The actual operating temperatures ranges of such batteries are determined in relation to local climate condition and compared with single lead–acid (Pb–acid) battery. The test results showed that significant limitations exist for current value both for Pb–acid and Li-ion battery. Coupling of supercapacitor module with Li-ion battery slightly improves the situation, but does not guarantee reliable three attempts for engine cold cranking.