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A method against dust pollution of dielectric surfaces has been proposed. The dust removal is achieved applying alternating electric fields of special geometry created by the linear electrodynamic Paul traps, which polarize dust particles on the surface of the dielectric and draw them into the interelectrode space of the trap. The captured dust can be moved without contact with the solar panel surface toward the electrodes ends in a special container by an additional constant electric field. The feasibility of the approach was demonstrated by a series of experiments on the removal of aluminium oxide and sand particles of various sizes from a glass surface and solar panels. The cleaning rate for 70 90 μm particles uniformly scattered on the glass substrate inclined at 20∘ was 92%. The capture of a single particle was analyzed using numerical simulations and the conditions necessary for its capturing and levitating were determined.

The possibility of charged particles trapped by the linear quadrupole Paul trap to form an ensemble with strong Coulomb interaction at atmospheric pressure has been experimentally shown. The ordered structure could confine particles of different sizes and charges. Stable clouds of thousands of oxide aluminum particles with sizes of 0.5÷65 microns were observed in the linear trap with electrodes placed 30 mm apart. (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We are going to study the kinetic properties of dense hydrogen plasma by a new quantum dynamics method in the Wigner representation of quantum mechanics. This method combines the Feynman and Wigner formulation of quantum mechanics and uses for calculation the direct path integral Monte Carlo (PIMC) and molecular dynamics methods. We are going to solve the Wigner–Liouville equation for dense degenerate hydrogen with the initial condition sampled by the PIMC method from equilibrium plasma state. We hope to do calculations of the hydrogen plasma properties under extreme conditions.

Noble metals that are deposited on a polymer surface exhibit surface diffusion and diffusion into the bulk. At the same time the metal atoms tend to form clusters because their cohesive energy is about two orders of magnitude higher than the cohesive energy of polymers. To selfconsistently simulate these coupled processes, we present in this paper a Kinetic Monte Carlo approach. Using a simple model with diffusion coefficients taken as input parameters allows us to perform a systematic study of the behavior of a large ensemble of metal atoms on a polymer surface eventually leading to polymer nanocomposites. Special emphasis is placed on the cluster growth, cluster size distribution and the penetration of clusters into the substrate. We also study the influence of surface defects and analyze how the properties of the resulting material can be controlled by variation of the deposition rate (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The results of investigations of dust grain behavior in plasma formed by a proton beam in inert gases (He, Ar, Kr) are demonstrated. Stable ordered dust structures, namely “a plasma-dust crystal” formed of dust grains 1.0, 3.0, and 4.8 μm in diameter are obtained in the proton beam range for the first time. The mathematical model which allows for numerical simulation of crystal formation from dust grains formed by proton beam plasma is developed.

The internal energy and equation of state of dense hydrogen are investigated by direct path integral Monte Carlo method simulations which are further improved in comparison to our previous results. Data for four isotherms – T = 10, 000K, 30, 000K, 50, 000K, and 100, 000K – are presented. For T = 10, 000K it is shown that the internal energy is lowered due to droplet formation for densities of the order 1023cm–3 giving direct support for the existence of a plasma phase transition in megabar hydrogen. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Plasma phase transitions in dense hydrogen and electron–hole plasmas are investigated by direct path integral Monte Carlo methods. The phase boundary of the electron–hole liquid in germanium is calculated and is found to agree reasonably well with the known experimental results. Analogous behaviour is found for high-density hydrogen. For a temperature of T = 10 000 K it is shown that the internal energy is lowered due to droplet formation for densities between 1023 cm−3 and 1024 cm−3.

Direct fermionic path-integral Monte-Carlo simulations of strongly coupled hydrogen are presented. Our results show evidence for the hypothetical plasma phase transition. Its most remarkable manifestation is the appearance of metallic droplets which are predicted to be crucial for the electrical conductivity allowing to explain the rapid increase observed in recent shock compression measurments., Comment: 1 LaTeX file using jetpl.cls (included), 5 ps figures. Manuscript submitted to JETP Letters

Ordered dusty structures formed of spherical monodisperse and polydisperse grains are obtained for the first time in a nuclear-track plasma produced by α-particles and fission fragments of 252Cf nuclei passing through neon or argon. A theoretical model of such a plasma is proposed. Monte Carlo computer simulations based on this model are carried out to explain the formation of such structures.

Using a novel path integral representation of the many-particle density operator, we calculate the pair distribution function of Fermi systems which are both strongly coupled and strongly degenerate . Numerical results are presented for a dense two-component electron–proton plasma at temperatures k B T >0.1 Ry.

Results are presented from the experimental studies and numerical simulations of the behavior of dust grains in the plasma of an inductive RF discharge. The experiments were carried out with neon at a pressure of 25–500 Pa and with 1.87-µm melamine formaldehyde grains. The discharge was excited by a ring inductor supplied from a generator operating at a 100-MHz frequency. The effective dust-grain interaction potential used in numerical simulations involved the spatial dependence of the grain charge on the plasma floating potential, grain-interaction anisotropy resulting from the focusing of the drift ion current by the negatively charged grains, and specific features of the shielding of the dust grains by the plasma electrons and ions recombining both in the plasma bulk and on the grain surface. The results of Monte Carlo simulations show that the dust grains form specific filament structures observed experimentally in the plasma of an inductive electrodeless discharge.

Conditions of the charged particles confinement in a vertically oriented microparticle electrodynamic ion trap have been determined experimentally. The experiment included two stages. At the first stage, charge-to-mass ratio of the trapped particle was measured by its position in a non-uniform electric field while at the second stage the ac voltage frequency was varied until the particle fell out of the trap. This frequency was taken as the boundary of particle confinement.

In this article, the possibility of nanoparticle confinement by electrodynamic Paul trap is shown. The areas of nanoparticle confinement as the dependencies of particle charge density on voltage frequency and geometry of the trap are found. The nanoparticle charge density for its confinement should be of order (1013-1014)e/m2.

We considered the possibility of using a corona discharge in a nuclear excited dusty plasma to provide the stability of well ordered dusty plasma structures from a fissionable material and to accomplish a more efficient conversion of nuclear energy into radiation.

In this paper, we present the experimental results demonstrating the charged microparticles confinement in an electrodynamic trap in a gas flow and prove the selective possibility of these traps to capture charged microparticles in gas flows in a wide range of microparticle and trap parameters.

In this work we calculate the thermodynamic properties of hydrogen-helium plasmas with different mass fractions of helium by the direct path integral Monte Carlo method. To avoid unphysical approximations we use the path integral representation of the density matrix. We pay special attention to the region of weak coupling and degeneracy and compare the results of simulation with a model based on the chemical picture. Further with the help of calculated deuterium isochors we compute the shock Hugoniot of deuterium. We analyze our results in comparison with recent experimental and calculated data on the deuterium Hugoniot., Comment: 7 pages, 5 Postscript figures, accepted for publication in J. Phys. A: Math. Gen

Summary form only given. The internal energy and equation of state of dense hydrogen and hydrogen-helium mixture are investigated by direct path integral Monte Carlo method which are further improved in comparison to our previous results. Data for four isotherms T=10,000 K, 30,000 K, 50,000 K and 100,000 K are presented. For T=10,000 K it is shown that the internal energy is lowered due to droplet formation for densities of the order 10/sup -23/ cm giving direct support for the existence of a plasma phase transition in megabar hydrogen. The thermodynamic properties of warm dense matter, such a hydrogen and hydrogen mixture at megabar pressure, are essential for the description of plasmas generated by strong lasers, ion beams or free electron lasers. Among the phenomena of particular current interest are the high-pressure compressibility of deuterium, metalization of hydrogen, Wigner crystallization plasma phase transition etc., which occur in situations where both interaction and quantum effects are relevant and a crossover from a neutral system to full ionization takes place. We use the direct fermionic path integral Monte Carlo simulations to investigate the dense plasmas in a wide range of densities and temperatures.

We study thermodynamic properties and the electrical conductivity of dense hydrogen and deuterium using three methods: classical reactive Monte Carlo (REMC), direct path integral Monte Carlo (PIMC) and a quantum dynamics method in the Wigner representation of quantum mechanics. We report the calculation of the deuterium compression quasi-isentrope in good agreement with experiments. We also solve the Wigner-Liouville equation of dense degenerate hydrogen calculating the initial equilibrium state by the PIMC method. The obtained particle trajectories determine the momentum-momentum correlation functions and the electrical conductivity and are compared with available theories and simulations.

This paper is devoted to first-principles calculations of hydrogen and helium thermodynamics. We use the direct path integral Monte Carlo method to compute isochors and isotherms in a wide range of parameters in comparison with available theoretical and experimental results. New results for hydrogen and hydrogen-helium plasmas with the mass concentration of helium Y=0.988 are analysed with the help of a model based on the chemical picture.

Results are presented from Monte Carlo calculations of the electric charge on dust grains in a plasma produced during the slowing down of radioactive decay products of californium nuclei in neon. The dust grain charging is explained as being due to the drift of electrons and ions in an external electric field. It is shown that the charges of the grains depend on their coordinates and strongly fluctuate with time. The time-averaged grain charges agree with the experimental data obtained on ordered liquid-like dust structures in a nuclear-track plasma. The time-averaged dust grain charges are used to carry out computer modelling of the formation of dynamic vortex structures observed in experiments. Evidence is obtained for the fact that the electrostatic forces experienced by the dust grains are potential in character. The paper is supplemented by a video clip showing the typical dynamics of the simulated vortex dust structure.

This work is devoted to an analysis of the thermodynamic and transport properties of high-density low-temperature gases and plasmas. The results of two independent theoretical methods are discussed and compared: path integral Monte Carlo data and results from a new chemical model which takes into account free charged particles, atoms, molecules and molecular ions. The two approaches show good agreement for the equation of state of hydrogen up to the multimegabar range. At low temperature, both show indications of a first-order phase transition. Furthermore, based on the chemical model the electrical conductivity of dense hydrogen and deuterium and the deuterium shock hugoniot are computed.

Results are presented from numerical simulations of the thermodynamic properties of superdense hydrogen and deuterium plasmas by the Monte Carlo method and from calculations by a multicomponent chemical model. The results obtained reveal the anomalous behavior of the thermodynamic functions and composition of molecular gas plasmas in the submegabar and megabar pressure ranges. Such behavior is interpreted as a dissociative phase transition. The results of calculations by the chemical model are compared with the experimental data on the equation of state and conductivity of hydrogen and deuterium plasmas.