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The action of the light pressure force on a bounded region of a 2D system of dust macroparticles is simulated using the molecular dynamics method. The dynamics of dust macroparticles in the quasi-2D structure (trajectories of particles, their mean square displacement, and kinetic energy) is analyzed for various values of the nonideality parameter and laser radiation power. It is shown that by varying the radiation power, it is possible to influence the self-diffusion processes and the value of chaotic velocity of particles. Analysis is performed for different initial values of the nonideality parameter of the unperturbed dust subsystem. It is found that the interparticle interaction results in an increase in the kinetic energy of particles in the region of action, as well as beyond it.

We have studied experimentally the oscillatory process in the dusty plasma in the glow discharge stratum. It is shown that the oscillations are induced by the dust–acoustic instability, as a result of which dust–acoustic solitons are excited. The motion of dust particles in the electric field of solitons has been analyzed. It has been established that a soliton leads to a large-scale unidirectional transport of charged particles in the direction of its motion. The experimental results have been interpreted theoretically using the MHD model of the plasma.

We report on the results of analysis of the mean kinetic energy and the pair correlation function of polymer particles in a plasma–dust structure under the action of laser radiation. We have observed experimentally the crystal–liquid phase transition in the monolayer of particles levitating in the near-electrode layer of a capacitive high-frequency discharge. The coupling parameter of the dust system has been estimated. The results of analysis of the modification of the polymer dust particle surface after holding in the plasma are considered. We propose an explanation of the phase transition taking into account the role of the photophoretic force in the motion of macroparticles. The effect of the photophoretic force is associated with the modification of the dust particle surface in the plasma, as a result of which the particles can effectively absorb laser radiation.

The dusty plasma structures in a glow discharge of helium in a tube cooled by superfluid helium at a temperature of 1.6 K and higher have been studied experimentally. The bimodal dust plasma formed by clouds of polydisperse cerium dioxide particles and polymer nanoparticles has been analyzed. We have observed wave oscillations in the cloud of polymer nanoparticles (with a size up to 100 nm), which existed in a narrow temperature range from 1.6 to 2.17 K. Vortices have been observed in the dusty plasma structures at helium temperatures.

The effect of a dc electric field on strongly nonideal Coulomb systems consisting of a large number (~104) of charged diamagnetic dust particles in a cusp magnetic trap are carried out aboard the Russian segment of the International Space Station (ISS) within the Coulomb Crystal experiment. Graphite particles of 100–400 μm in size are used in the experiments. Coulomb scatter of a dust cluster and the formation of threadlike chains of dust particles are observed experimentally. The processes observed are simulated by the molecular dynamics (MD) method.

Properties of weakly dissipative dust-acoustic solitons are analyzed on the basis of the hydrodynamic and single-particle approximation (Lagrangian–Euler approach). Significant differences between dissipative and conservative solitons are found. Particle-wave microdynamic parameters such as trajectories, phase trajectories, and drift velocity of dust particles under the action of a cascade of solitons are calculated. It is shown that dissipation is responsible for the interconnection of solitons in the ensemble. In addition, dissipative solitons significantly affect the environment comparing with conservative ones. The heat release processes that determine the production of entropy are analyzed. The role of dissipation in the ordering of charged particles trajectories is revealed. The theoretical results are in a reasonable agreement with known experimental data.

The results of experimental and numerical analysis are presented for phase transitions in strongly nonequilibrium small systems of strongly interacting Brownian particles. The dynamic entropy method is applied to analysis of the state of these systems. Experiments are carried out with kinetic heating of the structures of micron-size particles in a laboratory rf discharge plasma. Three phase states of these small systems are observed: crystalline, liquid, and transient. The mechanism of phase transitions in cluster structures of strongly interacting particles is described.

We consider the results of experimental observation of melting of a plasma-dust monolayer (2D phase transition) in a low-pressure gas discharge. Pair and bond-angular correlation functions as well as the number of topological defects in the monolayer are measured and analyzed. The change of profile of the bond-angular correlation functions confirms the existence of the solid-hexatic phase-liquid phase transition, which completely correlates with the Berezinskii-Kosterlitz-Thouless theory.

Nonthermal plasmas (NTPs) represent a perspective class of antibacterial agents that might be an alternative to chemical disinfectants because they possess an unspecific antimicrobial activity and can be applied to decontamination of heatand chemical-sensitive surfaces as well as to the infected skin and wounds. The resistance to NTP depends on properties of both a microorganism and a certain plasma source. Two bacterial species, Pseudomonas aeruginosa and Staphylococcus aureus, which are among the most important causative agents of nosocomial infections, were tested with three different plasma sources. The ferroelectric air plasma generator, the microwave argon plasma source, and the generator of a positive and negative corona discharge in air demonstrated increasing activity toward tested bacteria. The relative resistance of the tested strains to NTPs produced by distinct plasma sources differed. P. aeruginosa was more resistance to the corona discharge and less resistant to the plasma generated by the ferroelectric generator than S. aureus while both strains demonstrated comparable resistance to microwave argon plasma. Obtained results demonstrated a role of charged particles as a primary factor in the high effectiveness of the positive and negative coronas and an importance of the NO• radical among neutral active species.

Formation of large-scale dust vortices in the striation of dc glow discharges was experimentally investigated. Dust clouds were formed by monodisperse MF particles with diameters ≈2 µm in the regions of stable striation. Vortices obtained were about 1 cm in size and contained ~104 particles. Structural (vortex configuration, dust particle flow filaments) and dynamic (rotation frequencies and velocity spectrum) characteristics of large-scale dust vortices were measured.

A series of experiments on the modernized "Coulomb crystals" setup on board of the International Space Station (ISS) was performed. Formation of a cluster of charged and uncharged particles was observed. Excitation and damping of cluster oscillations, as well as its destruction in the high electric field were investigated. Charges of the particles were evaluated on the basis of their rate of expansion from the cluster. Some conclusions about the cluster structure have been presented.

Two-stage melting is observed experimentally in a confined monolayer of dust particles in plasma. The pair correlation and bond-angular correlation functions, the number of topological defects, and the pair potentials are measured and analyzed. The bond-orientational correlation functions show a clear solid-to-hexatic-to-fluid transition, in perfect agreement with the Berezinskii-Kosterlitz-Thouless transition theory.

Results of experiments on the formation of dusty plasma structures in a stratified dc discharge in axial magnetic fields up to 2500 G are presented. The rotation of the rather small and planar dusty plasma structures has been observed. As the field increases, the inversion of the structure rotation occurs, and when it reaches 700 G, the displacement of dust particles from the axial region of the discharge to the periphery, along with the rotation continuation, is observed. The explanation of the features in the dynamical behavior of the dust particles in the discharge, in particular the rotation inversion, is proposed.

For confinement and investigation of strongly coupled systems of charged macroparticles, we propose to use a trap based on the known possibility of the levitation of diamagnetic bodies in a nonuniform steady-state magnetic field. An experimental setup is described, which is capable of forming and confining clusters of charge graphite particles sized 100 to 300 μm in magnetic field B~1 T and |∇B| ~ 10 T/cm. It is inferred that it will be possible to form stable 3D structures containing several thousands macroparticles under terrestrial conditions by using fields B>10 T, and under microgravity conditions by using fields B~0.1 T.