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A four-channel scheme of an experiment aimed at obtaining optical and X-ray spectra and images of radiation generated in optical breakdown plasma channels in Bessel beams formed by focusing electromagnetic radiation by means of axicon-type conoid focusing systems is developed.

Studies of the lifting force of an electrohydrodynamic thruster based on a corona discharge in wire-to-cylinder geometry in a rarefied atmosphere have been carried out. Electrohydrodynamic cell parameters at three interelectrode gaps of 50, 100, and 150 mm and at pressures from 1 to 0.05 atm with positive corona discharge were investigated. The experimental system included a vacuum chamber, an EHD thruster, a high voltage power source (HVDC), and a thrust, voltage, and current acquisition system was created. The effectiveness of the thruster reached 26 mN/W at atmospheric pressure at a 150 mm gap. At a pressure of 0.05 atm (corresponds to an altitude of 20 km) the maximum thrust per unit length was 1.8 mN/m and the thrust-to-power ratio was 0.5 mN/W. Theoretical and experimental data on the normalized effectiveness on the altitude of the thruster were obtained.

In this work, systems with serial and alternating electrical connection of three electrohydrodynamic cells based on corona discharge in atmospheric pressure air were studied. Numerical simulations of the systems was conducted. The volume force acting in the drift regions of the multi-cascade system was calculated and a good agreement was obtained between experimental and theoretical data.

This paper presents methods of detection and spectrometry of high-energy electrons and positrons produced in the interaction of laser radiation with matter and vacuum. The methods are based on charged particle transport in the magnetic field of a hollow coaxial line through which a direct current flows. The methods make it possible to detect particles at a distance of several dozen meters from the source with retention of close to 100% collection efficiency and provide efficient detector protection from background radiation.

A powerful pulsed dc converter has been developed for charging battery assemblies on board of hybrid and electric aircraft, which enables full battery capacity charging in cruise mode of the aircraft. This 10-kW modular design converter can operate in a buck–boost mode in a voltage range of 130–300 V with a current limit of 70 A at an output voltage of 150 V. The efficiency of the created converter is ~96–99%, depending on the power consumed in the load. The proposed modular design and multiphase control circuit can be used to create converters with different capacities and high efficiency.

We simulated and experimentally studied the process of the interaction of a barrier discharge with natural gas in a plasma-chemical reactor with a coaxial electrode configuration. The obtained dependences of the hydrocarbon concentration on the average specific energy supplied to the discharge are linear. An explanation of the observed results is proposed.

A multidischarge actuator system (MAS) based on an improved three-electrode scheme with a screening electrode has been studied. The geometrical and physical parameters of the MAS are optimized to increase the velocity and energy efficiency of the generated airflow. The dependences of the airflow velocity at the output of the MAS on the frequency, voltage amplitude, and average supply power are experimentally determined. The maximum velocity is measured as a function of the total thickness of the dielectric substrate.

The efficiency of power transistors in composite high-voltage switches is analyzed. A high-voltage pulse generator capable of generating a periodic voltage signal with a rectangular shape, an amplitude as high as 16 kV, a current greater than 40 A, and a repetition rate of up to 100 kHz has been developed.

The conversion of hydrocarbons during the treatment of a methane–ethane mixture with a barrier discharge in an electrophysical setup was experimentally studied. The theoretical estimation of plasmakinetic processes occurring in a discharge was performed for the developed plasmachemical reactor using the ZDPlasKin algorithm. Experimental results were in agreement with theoretical estimates.

The effect of energy deposition on the composition of the outlet mixture was studied in a plasmachemical reactor with barrier discharge. The composition of the conversion products was analyzed using a gas chromatograph and a quadrupole mass spectrometer. The process mainly occurred by the thermal mechanism of chain initiation and propagation. At an energy input of 3.25 eV/molecule, the selectivity for the main reaction products was 11.56% for acetylene, 14.76% for ethylene, 30.51% for ethane, 16.84% for propylene, 15.01% for propane, and 7.02% for hydrogen.

The parameters of a number of high-voltage solid-state switches are studied. Based on the analysis of their work, a high-voltage pulse source with a size of 105 × 260 × 180 mm is assembled to supply cold plasma jets operating at the ac voltage of 220 V, 50 Hz.

Experimental results on the radial distribution of the nanosecond dielectric barrier discharge (DBD) current in flat millimeter air gaps under atmospheric pressure and natural humidity of 40–60% at a voltage rise rate at the electrodes of 250 V/ns are presented. The time delay of the appearance of discharge currents was observed to increase from the center to the periphery of the air gap at discharge gap heights above 3 mm, which correlated with the appearance of constricted channels against the background of the volume DBD plasma. Based on the criterion of the avalanche-streamer transition, it is found out that the development of a nanosecond DBD in air gaps of 1–3 mm occurs by the streamer mechanism.

The spatiotemporal dynamics of a nanosecond atmospheric-pressure dielectric barrier discharge in 1- to 3-mm-long air gaps was studied experimentally. By using a segmented electrode, data on the time evolution of the discharge in different regions of the discharge gap were obtained. The uniformity of the discharge over the cross section is estimated by analyzing the spatial distribution of its glow.

A mechanism of laser radiation absorption by a metal surface during the formation of surface nanostructures is proposed. The mechanism is based on the heterogeneous character of such absorption due to the formation of absorption zones in the old excited structure. It has been shown that the process of laser radiation absorption by metals can be of a nonlinear character.

Rocket and balloon measurement data on atomic-oxygen (λ 63 µm) emission in the upper atmosphere are presented. The data from the longest (1989–2003) period of measurements of the atomic-oxygen (λ 63 µm) emission intensity obtained by spectral instruments on sounding balloons at an altitude of 38 km at midlatitudes have been systematized and analyzed. Regularities in diurnal and seasonal variations in the intensity of this emission, as well as in its relation with solar activity, have been revealed.

A high-power electrodynamic flow in atmospheric air is numerically simulated and experimentally studied. An electrode system consisting of a cylindrical plasma emitter and a plane metal grid collector of ions is used to generate a flow with a speed of 2 m/s and a volume rate of 15 L/s.

A dielectric barrier discharge plasma reactor has been designed and constructed. The space discharge regime has been implemented. The reactor operating conditions for the desired reaction have been calculated using the dissociation of water molecules as a model reaction. The operating conditions have been selected for the dissociation of water vapor via excitation of vibrational levels of the molecule by a single electron impact.

A semiconductor rectangular-pulse generator with smoothly controlled output parameters for powering a barrier discharge was developed and investigated. The generator allows the formation of voltage pulses with the smoothly regulated amplitude (0–16 kV) and duration (600 ns–1 ms) across the discharge gap. The pulse rise and fall times can be varied from 40 ns to 1 μs. The generator pulse repetition rate can be smoothly varied from 0 to 50 kHz. The generator can operate in the manual-triggering mode and in the mode of pulse trains with an effective frequency of up to 500 kHz. The generator is intended for initiating and investigating a barrier discharge in millimeter-wide air gaps at the atmospheric pressure.

The results of experimental studies of the process of switching a composite semiconductor switch, which consists of series-connected insulated-gate bipolar transistors with artificially nonuniformly distributed operating parameters are presented.

The current distribution in a dielectric barrier discharge in atmospheric-pressure air at a natural humidity of 40–60% was studied experimentally with a time resolution of 200 ps. The experimental results are interpreted by means of numerically simulating the discharge electric circuit. The obtained results indicate that the discharge operating in the volumetric mode develops simultaneously over the entire transverse cross section of the discharge gap.

A compact source of low-temperature plasma for biological and medical applications is proposed, which operates at kilohertz frequencies in the regime of flash-corona discharge with an energy of 0.1 mJ/pulse. The plasma source was tested in application to plasma pretreatment of green salad seeds. Plasma-treated seeds exhibited increased (by about 25%) germination speed as compared to that in the untreated control.

Barrier-discharge stimulation of chemical reactions has been studied in the case of methane oxidation by atmospheric oxygen with the formation of carbon monoxide and hydrogen. Experiments in a plasmachemical reactor demonstrated the possibility of increasing the yield of synthesis gas (syngas) by means of plasma pretreatment of the initial mixture of air and methane in a 7: 1 ratio at atmospheric pressure. The output-gas composition was determined by gas chromatography. It is established that the plasma-discharge treatment of the initial gas mixture leads to a 15% increase in the amount of syngas at the reactor output and increases the reaction selectivity with respect to hydrogen and carbon monoxide by 3.2 and 6.5%, respectively.

Theoretical and experimental studies of an electrohydrodynamic flow induced by a high-frequency dielectric barrier discharge distributed over a dielectric surface in a gas have been conducted. Dependences of the ion current, the gas flow velocity, and the spatial distributions thereof on the parameters of the power supply of the plasma ion emitter and an external electric field determined by the collector grid voltage have been described.

In the given paper, recent results on the development of physical mechanisms and theoretical models of direct laser surface nanostructuring are reviewed. Attention is paid to nanosecond lasers, as they are cheaper and simpler in use than pico- and femtosecond lasers, which is important for the development of further applications. The formation of so-called 'nonresonant' structures, whose period is not directly related to the laser radiation wavelength, is considered. Nanostructuring mechanisms for a number of surface modification processes with and without melting are studied. Corresponding experimental illustrations of nanostructures are given for various materials – polymers, metals, ceramics, and diamond films.

The results of investigations on the possibility of an electrohydrodynamic force effect on a gas flow implemented with the help of a barrier discharge are presented. A new method of controlling the laminar flow around a base with suppression of instabilities of the incoming flow due to electrohydrodynamic force action on the boundary layer near the forward edge of a swept wing is proposed. An efficient multidischarge actuator system is developed and created for active control of aerodynamic flows with induced-air-flow characteristics exceeding the world analogues.

We analyzed and systemized the published data on satellite and rocket long-term measurements of the oxygen atom O( 3 P) (63 μm) and of the СО 2 molecule (15 μm) infrared (IR) emissions in the upper atmosphere. We revealed and presented empirical ratios describing the diurnal, seasonal, and latitudinal variations in the intensities of these emissions, their height distribution, as well as their dependence on solar activity. We analyzed photochemical atmospheric processes leading to the emergence of O( 3 P) (63 μm) and of СО 2 (15 μm) emissions in the upper atmosphere.

Possibility of forming quasi-periodic structures of micron and submicron dimensions on a surface of zirconium dioxide under the action of eximer ArF laser radiation is shown experimentally and theoretically.

A method that controls solid-state insulated gate bipolar transistor (IGBT) switches, allowing one to increase their ON-state duration time from fractions of microseconds up to milliseconds, is proposed. It is shown that the ON-state duration of the switches is limited only by their overheating. The modular design of the high-voltage solid-state switch with a 16-kV operating voltage and 60-A pulse current is experimentally implemented.

The degree of homogeneity of a diffuse dielectric barrier discharge in millimeter air gaps under atmospheric pressure has been analyzed. This analysis is based on the glow-brightness distribution in the discharge gap cross section with allowance for a cylindrical electrode shape. It is shown that the degree of discharge homogeneity depends on both the repetition frequency of voltage pulses applied to the discharge gap and the barrier material.

An experimental technique of passive optical diagnostics of plasma is proposed. The equipment complex designed for its practical implementation is described. The technique is based on the simultaneous recording of self-radiation spectra and images of plasma with the subsequent analysis of the recorded data. This technique can be applied for diagnosing plasmas generated by various means, such as a gas discharge, laser radiation, a shock wave, an explosion, and so on.

The possibility of submicron structure formation on the surface of ZrO2 under excimer nanosecond ArF laser (λ = 193 nm) irradiation is shown. A model for the surface nanostructure formation in the course of laser infusion of solids is proposed.

The generator of sawtooth wave with voltage of 1 kV and frequency of 300 kHz intended to power the pumping region of the electrohydrodynamic flow systems is presented in the work. By varying the storage inductor the range of the operating frequencies can be expanded from dozens of kilohertz to 1 megahertz. The generator also can operate at the resonance frequency, creating a quasi-sinusoidal signal form. The three-phase scheme are implemented. The phase shift can be regulated by the driving generator.

The results of experimental investigations of transient processes and static voltage distribution consideration in composite solid-state switch consisted of series connected insulated gate bipolar transistors (IGBT) under conditions of artificial operational factors distortion are presented. The stability of the series connected transistors assembly with no special balancing circuits or adaptive gate control was shown. In transient, reliable operation of the assembly supported by effect of voltage self-restriction across lagged devices, and due to tolerance of IGBT to short-circuit mode which bounded by the junction power dissipation efficiency. In voltage blocking mode the single transistor overheating does not upsets the balance of the series transistors assembly as a whole, because helps to negative temperature coefficient of IGBT the tendency to self-stabilizing is appear as consequence of dissipation power redistribution. The last require to presence of some operational voltage amplitude margin for a single IGBT in the switch design.

The formation of an electrohydrodynamic flow in atmospheric air by using a high-frequency barrier discharge distributed over the dielectric surface is investigated. The influence of variations in parameters of a fully solid-state pulse generator (with a peak voltage of 0–12 kV, a tunable repetition rate of 10–25 kHz, and a pulse duration of 7 μs) on the current of plasma ion emitter and velocity characteristics of airflow is considered.

Electrohydrodynamic flow in gas for a high-frequency barrier discharge distributed over the surface of a dielectric was investigated. An electric-discharge laser circulation system with a gas flow rate higher than 15 L s-1 was proposed.

The principle types of inhomogeneities formed in a volume self-sustained discharge are analyzed. Possible mechanisms and conditions for suppression of their development are considered. An ultimately homogeneous volume self-sustained discharge in CO2: N2: He mixtures where local plasma inhomogeneities are absent is obtained. At the energy contribution of 170 J/l, the duration of steady discharge burning in the CO2: N2: He = 1: 2: 3 mixtures at atmospheric pressure is 10 μs.

The possibility of forming nanostructures on the surface of solids by the action of nanosecond laser pulses causing the material to melt has been shown both theoretically and experimentally. The dependence that the characteristic sizes of the surface nanostructures have on the energy of the laser beam and duration is established. Experimental results on samples of various materials obtained by direct laser nano-structuring using an ArF laser and images of titanium samples with surface nanostructures are presented.

The review of the methods for obtaining the runaway electron beams in the gas discharge is performed. The new method is offered, using which the beam is first formed in a narrow gap (∼1 mm) between the cathode and the grid and then it is accelerated by the field of the plasma column of the anomalous self-sustained discharge in the main gap (10–20 mm long). The electron beams with an energy of about 10 keV and current density of 103 A/cm2 at a molecular nitrogen pressure of up to 100 Torr have been obtained experimentally. The results of research of the UV nitrogen laser with an excitation via runaway electron beam and radiation of energy of ∼1 mJ are given. The UV nitrogen laser generation with the energy of ∼1 mJ has been obtained by the runaway electron beams.

A mobile spectrophotometric complex, intended for simultaneous laboratory and field measurements of the photometric and spectral parameters of radiation of different sources has been designed and produced. Examples of its use for detecting silvery clouds occurring at altitudes of about 82 km, the Polaris aurora, and nightglow of the upper atmosphere in different spectral ranges are given. Images of a solid-fuel rocket launch at the Plesetsk site, taken with the complex at the Zvenigorod station of Institute of Atmospheric Physics, Russian Academy of Sciences (IAP RAS), are presented.

On the basis of measurements of the intensity of 1.58-μm emissions of the Infrared Atmospheric System of molecular oxygen (IRAO2) conducted at the Zvenigorod scientific station of the Institute of Atmospheric Physics of the Russian Academy of Sciences (φ = 55.7°N, λ = 36.8°E), seasonal variations are estimated for various solar zenith angles. Their amplitude has the maximum value at the solar zenith angles χS ∼ 105–110°. It decreases at χS ∼ 125–130° and tends to zero at χS ∼ 80–85°. The comparison of currently measured values of the 1.58-μm emission intensity of the Infrared Atmospheric System of molecular oxygen with published data on the intensity of this emission obtained in 1961–1966 reveals their decrease over approximately 50 years. This fact is in good agreement with similar behavior of the emission intensity of atomic oxygen (557.7 nm) over the period considered.

The possibility of increasing the pulse duration of an ArF laser (wavelength 193 nm) by using an artificial forming line with nonlinear chokes is studied. An ArF laser (maximum pulse energy 15 mJ, pulse duration 18 ns, pulse repetition rate 1 KHz) with an all-solid-state pump generator is described.