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The thermal decomposition of acetylene to hydrogen and acetylene soot was studied, and the results of this study are presented. The experiments on acetylene decomposition were performed in a modified internal combustion engine (ICE) and in a flow-type reactor with external heat supply at a constant temperature (1000 ± 10°C). The experiments were performed without any oxidant additions. In the experiments with ICE, the engine work on acetylene was shown to be possible, and the composition of the gaseous reaction products was determined. In the experiments with a flow-type reactor, the effects of pressure in the reactor, acetylene flow rate, and the presence of a tungsten gauze in the working zone of the reactor on the degree of acetylene decomposition and the composition of gaseous reaction products was determined. Some properties of soot were analyzed: specific surface area, average particle size, bulk density, and combustion heat.

A differential two-photon method of measuring the temperature of 40Ca atoms in a continuously operating magneto-optical trap is demonstrated. Coherent two-photon resonances at the 4s2 1S0-50 1S0 Rydberg transition have been investigated experimentally using resonance laser beams propagating at different angles. The tempera­ture of the cloud of 40Ca atoms was measured depending on the frequency detuning of the cooling laser radiation.

The control spectral shifts of resonant radiation frequency due to spatially non-uniform and non-stationary centrifugal acceleration, stipulated by the travel of radiation source along the centrifugal radius or modulation of the rotation frequency, are examined. These spectral variations pave the way to modeling of effects of non-uniform and non-stationary gravity field. The perspectives of flexible control of spectral lines shifts for the analysis of fine structure of radiation and absorption spectra are considered.

Opening speech of the chairman of the priority council of RAS academician V.E. Fortov

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.

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.

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The physical properties of hot dense matter over a broad domain of the phase diagram are of interest in astrophysics, planetary physics, power engineering, controlled thermonuclear fusion, impulse technologies, enginery, and other applications. The present report reviews the contribution of modern experimental methods and theories to the problem of the equation of state (EOS) at extreme conditions. Experimental techniques for high pressures and high energy density cumulation, the drivers of intense shock waves, and methods for the fast diagnostics of high-energy matter are considered. It is pointed out that the available high pressure and temperature information covers a broad range of the phase diagram, but only irregularly and, as a rule, is not thermodynamically complete; its generalization can be done only in the form of a thermodynamically complete EOS. As a practical example, construction of multi-phase EOS for tungsten is presented. The model's results are shown for numerous shock-wave data, the high-pressure melting and evaporation regions and the critical point of tungsten.

The structure and properties of the shock wave front propagating in binary gas was investigated by multi-channel emission spectroscopy and electrostatic probe located in a flow core. The experimental conditions allowed to consider the energy exchange processes in the front like interaction of isolated cold heavy molecules Mo (CO)6 with shock wave front of light noble gas (He, Ar). Measurements were carried out in a weak incident shock waves (Mach number M = (2.5 ÷ 3.6) in the high vacuum shock tube at equilibrium temperature of 850–1400 K and pressure of 0.1–1.1 bar, Mo(CO)6 concentration 5.0 × 1013−3.0 × 1014 cm−3. An influence of heavy molecules on thermodynamics was negligible and free paths of “heavy” molecules between collisions “heavy-heavy” were longer then 1 mm. Nearby shock wave front the conductivity and the electron precursor zones caused by ionization and charge separation were detected and measured. The dependence of probe current on the energy of pair collisions was found. The length of charge separation in SW front was measured and free electrons concentration was estimated.

In present work the formation of dusty plasma structures in cryogenic glow dc discharge was investigated. The ordered structures from large number (∼104) of charged diamagnetic dust particles in a cusp magnetic trap have been also studied in microgravity conditions. The super high charging (up to 5·107e) of dust macroparticles under direct stimulation by an electron beam is experimentally performed and investigated. The results of the investigation of Brownian motion for strongly coupled dust particles in plasma are presented. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The main technological causes of the accident at the Sayano-Shushenskaya hydropower plant are considered, and directions of the scientific support of the plant’s restoration are determined in this article. In the opinion of the authors, a safety system similar to those at other large power-generating and industrial facilities should be quickly developed and introduced in the plant’s operation.

We report on high-field terahertz transients with 0.9-mJ pulse energy produced in a 400 mm² partitioned organic crystal by optical rectification of a 30-mJ laser pulse centered at 1.25 μm wavelength. The phase-locked single-cycle terahertz pulses cover the hard-to-access low-frequency range between 0.1 and 5 THz and carry peak fields of more than 42 MV/cm and 14 Tesla with the potential to reach over 80 MV/cm by choosing appropriate focusing optics. The scheme based on a Cr:Mg₂SiO₄ laser offers a high conversion efficiency of 3% using uncooled organic crystal. The collimated pump laser configuration provides excellent terahertz focusing conditions.

The problem of the high-velocity interaction of various technogenic bodies with targets and constructions usually consisting of a set of simple targets (layered, screened, and spaced) made of various materials is of special importance in the general problem of highvelocity impact phenomena. It is a scientific basis for solving practical problems concerning the development of double-purpose technologies and permanent advancements in the protection of civil, marine, aviation, and space equipment against penetrating impacts of various technogenic bodies. Complex experimental and numerical investigations into the damages caused to finite-thickness targets by projectiles show that mechanisms of the destruction of targets change significantly with variation in the initial conditions of interaction (increase in the collision velocity of bodies, change in the materials of targets and projectiles, their shape, etc.) [1]. Since a high-velocity impact proceeds very quickly (over a time period of about 10 —4 —10 —7 s) and results in destructive action, experimental information on the dynamics of the entire impact process is primarily obtained by high-speed optical shooting (ordinary and laser), pulsed multiple radiography [2], and recording of pressures and velocities by differential laser interferometry, manganin, capacity, and piezoelectric and electret sensors [3]. In addition, mathematical simulation by modern numerical methods is an important source of information immediately from any zone of active deformation, prefracture and fracture of materials of interacting bodies [4]. Computer simulation of the interaction of projectiles with targets and simple constructions was performed by the numerical finite-element method, which was efficiently applied to various impact problems [5]. The physical‐mathematical model of colliding solids that is used in this work is generally represented by a compressible strong medium whose behavior under extreme impact loads is described by a broadband semiempirical equation of state [6], elastoplastic model, dynamic yield stress, shear modulus, and constants of the kinetic fracture model [7]. The last model describes the local formation, development, and target evolution of microdamages, which continuously change the properties of the materials in contact and induce a relaxation of stresses. The spall‐shear fracture process was simulated based on the concept of a continuous accumulation of damages characterized by the specific volume of cracks [7]. The rate of increase in the specific volume of cracks or pores was specified as a function of acting pressure and the volume of damages attained according to relations obtained in [7, 8]. These relations take into account the possibility of partial or complete closure of microdamages upon change in the sign of tensile stresses and the appearance of compressive stresses [9], which is very important for analysis of the perforation of spaced constructions. Step-by-step analysis of contours of the specific volume of cracks (at different times) at the stage of prefracture of materials makes it possible to locally determine the general developmental tendencies of fracture both qualitatively and quantitatively, as well as its mechanism, the local damage degree of a material, and the behavior of the main spall crack and adiabatic shift due to decrease in the strength of the material that is caused by its adiabatic heating [10]. In addition, the formation and evolution of different fracture mechanisms and their interference are revealed. In particular, analysis of a mechanism of the perforation of plates by deformable projectiles revealed that the formation of a separated disc in the upper and lower halves of a plate occurred through different mechanisms [11].

MHD-effects associated with the movement of a weakly conducting cylindrical body in a planetary atmosphere are analyzed numerically. The longitudinal axis of the body is perpendicular to the direction of motion and the field lines of the planetary magnetic field. In the calculations we used data similar to those for the collision of the Shoemaker-Levy 9 comet with Jupiter. The simulation is developed for two atmospheric levels: H∼100 km (magnetic pressure number RH≤1) and H∼280 km (RH∼1). It is shown that the maximum strength of the induced magnetic field is 2–3 orders of magnitude greater than the planetary magnetic field. For small RH, analytical expressions giving a fairly reliable estimate for the field strength in the shock-compressed space ahead of the body are obtained.

When high-power ion beams (HPIB) collides with matter, it generates plasma with parameters of a wide range, staring with those well mastered in physics and gas discharge technologies and ending with those appropriate to such natural systems as star nucleus and thermonuclear systems in feasible power projects based on the controlled inertial thermonuclear synthesis. We are interested in a fairly wide range of beam power densities (from 1 GW/cm 2 to 10 TW/cm 2 ). This paper describes one mathematical model in one dimension (a plane geometry is assumed) and one model in two dimensions (r- and z-coordinates). The models are completed by wide- range equations of state for real matter (construction materials) and supplemented with additional equations describing rheological, thermophysical, and optical properties of solid media under consideration (in various phase states from solid to plasma, including states of a strongly nonideal plasma). On the base of the continual approach, mechanical destruction of materials clue to tensile strain generated by rarefaction waves is taken into account. In modeling the action of ion beams of moderate intensity (I 10 GW/cm 2 (in the two- dimensional model based on the large-particle technique) heat transfer, including radiational processes, is considered. Opportunities offered by contemporary computer simulation techniques in the field of interaction between HPIB and matter are demonstrated, in particular, a possibility of simulating hypervelocity impact with the help of HPIB has been shown and the necessary conditions have been determined. The results of our computer simulation may be interesting from the viewpoint of some technological applications of HPIB, for example, pulsed destruction and strengthening of construction materials, pulsed ion implantation and etc. [1].

A system of hydrodynamic equations for the description of adron—adron collisions at the stage characterized by the existence of quark — gluon plasma is described. Unlike the well-known Landau model, the proposed scheme is the first to enable successive incorporation of the charge (electric and color), spin and isospin of the quarks, as well as interaction between quarks and the color and electromagnetic fields.

Non-thermal plasma (NTP) consists of a huge amount of biologically active particles, whereas its temperature is close to ambient. This combination allows one to use NTP as a perspective tool for solving different biomedical tasks, including antitumor therapy. The treatment of tumor cells with NTP caused dose-dependent effects, such as growth arrest and apoptosis. However, while the outcome of NTP treatment has been established, the molecular mechanisms of the interaction between NTP and eukaryotic cells have not been thoroughly studied thus far. In this work, the mechanisms and the type of death of human colon carcinoma HCT 116 cells upon application of non-thermal argon plasma were studied. The effect of NTP on the major stress-activated protein p53 was investigated. The results demonstrate that the viability of HCT116 cells upon plasma treatment is dependent on the functional p53 protein. NTP treatment caused an increase in the intracellular concentration of p53 and the induction of the p53-controlled regulon. The p53-dependent accumulation of active proapoptotic caspase-3 was shown in NTP-treated cells. The study was the first to demonstrate that treatment of human colon carcinoma cells with NTP results in p53-dependent apoptosis. The results obtained contribute to our understanding of the applicability of NTP in antitumor therapy.

Experimental data on the compression of solid deuterium at a pressure of ∼60 GPa are presented. The data were obtained on a generator of powerful converging spherical shock waves. The results are compared with the data of shock experiments obtained on a Nova laser facility and an electrodynamic EPBF-Z plant.

Results of application of LTP at atmospheric pressure as an antibacterial agent during the last decade are considered with reference to physicochemical mechanisms of its bactericidal action. The principles of designing modern LTP sources are described in conjunction with the results of LTP application against pathogenic bacteria in vitro and in biofilms. The possibility to destroy biofilm matrix by LTP is estimated along with the results of its testing for the treatment of acute and chronic wound surfaces. Prospects for the development of "plasma medicine" in this country and abroad are discussed with special emphasis on its advantages, such as the absence of long-acting toxic compounds, small probability of spontaneous mutations accounting for resistance to LTP, relatively low cost of LTP sources, independence of LTP effect of the surface relief, painless application.

Numerical and experimental investigations of the DC discharge in Neon in the tube with radius unevenly changed from 13.8 to 30 mm are presented. A formation of a dusty structure in standing stratum has been observed and simulated.

New results from the recent experiments using the “Plasma Kristall‐4”, “PK‐4”, onboard of the parabolic flight plane A‐300 Zero‐G are presented. These are: a) structural and dynamics properties of dusty plasma clouds containing elongated dust particles—microrods; b) formation of a boundary‐free dust cluster due to attractive forces caused by ion fluxes in a bulk plasma region; c) shock wave in dusty plasma driven by the electrical manipulative electrode in polarity switching direct current discharge. Physical models of the observed phenomena are presented and discussed. Universal possibilities of the “PK‐4” setup are demonstrated.

We used a dusty plasma technique to obtain Al‐Cu‐Fe quasicrystal powder particles coated by nickel. The samples of macro‐composites were obtained from the powders by cold pressing and following annealing in hydrogen. The structure of the samples and tribological properties were investigated.

Results of experimental investigations of instabilities in cryogenic DC discharge were presented. Different types of dusty plasma instabilities (self‐excited oscillations, vortices and complex oscillations) were observed. The dependence between frequencies of oscillations and the gas pressure for structures with self‐excited oscillations at temperatures from 10 to 300 K was obtained. It was revealed that decreasing of gas temperature can lead to damping of self‐excited oscillations. A relative gradient of the particles charge causing the dusty plasma instabilities was estimated.