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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.

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.

The purpose of this work was to establish the influence of a regime of cold microwave argon plasma treatments on the physiological characteristics of human fibroblasts and keratinocytes. We used three regimes of plasma application: a single treatment, double treatment with a 48 h interval, and daily treatments for 3 d. Cell proliferation after plasma application was quantified in real time, and immunohistochemistry was used to establish the viability of the cells and determine changes in their physiology. It was established that the frequency of cell treatments is important for the outcome. In the samples treated with single plasma application and double plasma applications with a 48 h interval, a 42.6% and 32.0% increase was observed in the number of cells, respectively. In addition, there were no signs of deoxyribonucleic acid breaks immediately after plasma application. In contrast, plasma application increased the accumulation of cells in the active phases of the cell cycle. The activation of proliferation correlated with a decrease in the level of β-galactosidase, a senescence marker. This could be due to cell renovation after plasma application. Daily treatment decreased cell proliferation up to 29.1% in comparison with the control after 3 d.

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.

In the previous researches of cryogenic complex (dusty) plasma [1] we observed experimentally complex plasma systems formed in cryogenic environments. Particularly it was revealed from the experiments that dust structures with high concentration of macroparticles can be formed. So-called super dense dusty plasma structures in which interparticle distance is comparable with particle size were also observed. Thus concentration of particles was close to concentration of background plasma. Similar formations had unusual properties (sphere-like form, free boundaries, etc.) and represent new object in dusty plasma researches. In the present work new results on experimental investigations of dense dust structures at cryogenic temperatures were presented. The experiments were made by means of recently developed techniques and cryogenic facilities (optical cryostat). Possible nature of the unusual properties of super dense dusty plasma structures was discussed.

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.