Charged Gas Research Articles

Effects of externally applied electric and magnetic fields on boseeinstein condensation of charged bose gas

Effects of externally applied electric and magnetic fields on boseeinstein condensation of charged bose gas

ЧИСЛЕННОЕ МОДЕЛИРОВАНИЕ РАСПРОСТРАНЕНИЯ УДАРНОЙ ВОЛНЫ ИЗ ГАЗА В ЭЛЕКТРИЧЕСКИ ЗАРЯЖЕННУЮ И НЕЙТРАЛЬНУЮ ГАЗОВЗВЕСИ В ПЛОСКОМ КАНАЛЕ

In this paper, we consider the propagation of a shock wave from a pure gas into a heterogeneous mixture consisting of solid particles suspended in a gas and having an electric charge. The applied mathematical model takes into account the speed and thermal interaction of the carrier and dispersed components of the mixture. The force interaction of particles and gas was described by the Stokes force. The carrier medium was described as a viscous compressible heat–conducting gas. The equations of the mathematical model were solved by the explicit finite–difference method of the second order of accuracy, using the non–linear correction of the grid function. The system of equations of the mathematical model was supplemented by boundary and initial conditions for the desired functions. As a result of numerical simulation, it was found that in an electrically charged gas suspension there is a difference in gas pressure and velocity, “average density” and velocity of the dispersed component, compared with similar values in a gas suspension with an electrically neutral dispersed component. The revealed differences in the dynamics of neutral and electrically charged dusty media can be explained by the fact that the dispersed component of an electrically charged gas suspension is affected by both aerodynamic drag forces and Coulomb forces. Due to interfacial interaction, the dynamics of the carrier medium changes.

Численное исследование скоростного скольжения несущей и дисперсной фазы при взаимодействии ударной волны с электрически заряженной газовзвесью

In this paper, we consider the propagation of a shock wave from a pure gas into a heterogeneous mixture con-sisting of solid particles suspended in a gas and having an electric charge. The applied mathematical model takes into account the speed and thermal interaction of the carrier and dispersed components of the mixture. The mathematical model assumed a monodisperse composition of the solid component of the mixture, that is, it was assumed that all particles have the same linear size, shape and consist of one material. The force interaction of particles and gas included the Stokes force, the strength of the attached masses, as well as the dynamic force of Archimedes. The carrier medium was described as a viscous compressible heat-conducting gas. The equations of the mathematical model were solved by the explicit finite-difference method of the second order of accuracy, using the non-linear correction of the grid function. The system of equations of the mathematical model was supplemented by boundary and initial conditions for the desired functions: at the boundaries of the computational domain, the Dirichlet boundary conditions were set for the velocity components of the carrier and dispersed phase for the remaining dynamic functions Neumann conditions were set. For the Poisson equation describing the distribution of the internal electric field of a charged gas suspension, homogeneous Dirichlet boundary conditions were specified. As a result of numerical calculations, differences were revealed in the velocity slip of the carrier and dispersed phases, in cases where the shock wave propagates into a neutral and electrically charged dusty medium. It was also revealed the effect of particle size on the speed of sliding of the carrier and dispersed components of a heterogeneous mixture during the propagation of a shock wave into a neutral and electrically charged gas suspension.

Electronic Decay of Singly Charged Ground-State Ions by Charge Transfer via van der Waals Bonds.

We report the observation of the radiative decay of singly charged noble gas ground-state ions embedded in heterogeneous van der Waals clusters. Electron-photon coincidence spectroscopy and dispersed photon spectroscopy are applied to identify the radiative charge transfer from Kr atoms to a Ne_{2}^{+} dimer, which forms after single valence photoionization of Ne atoms at the surface of a NeKr cluster. This mechanism might be a fundamental decay process of ionized systems in an environment.

Weak Shock Waves in Charged Gas

The problem of plane discontinuities of relatively small amplitude propagating in a layer of nonuniformly charged gas in the variable electric and constant gravity fields is considered within the framework of ideal electrohydrodynamics model. The transport equations of variational nature are derived for their amplitudes and an exact solution of the problem of weak discontinuity is given. Then, the problem of weak shock wave is solved in the approximation to the solution obtained. Examples of propagation of a wave through an arbitrary equilibrium initial state and along a gas layer moving as a solid body in a variable electric field are considered.

Study on application of colloidal particles of metal oxides to increase the oil recovery factor

The extraction of heavy oil, including bitumen, is complicated by the extremely high viscosity of the fluid in the reservoir. The adsorption of heavy oil fractions on the surface of minerals leads to the hydrophobization of the pore space. The magnetic colloidal particles of iron oxides present in the composition of the water remove adsorbed oil from the surface of pores, which manifests itself as an increase in the oil recovery factor and the injectivity of injection wells. Iron particles of submicron size, located on the surface of an electrically charged gas bubble, are concentrated at the water-oil interface. Due to the high adsorption energy on the surface of the iron particle, oil is deposited on the iron oxide particles. The drop-in bottom pressure of injection and production wells contributes to the movement of the gas bubble with oil and iron oxides to the bottom of production wells. The study of the mechanism of exposure to electromagnetic radiation showed that the electromagnetic field selectively heats the particles of iron oxide, causing catalytic cracking of oil, and contributes to an increase in the oil recovery factor and well productivity index.

Interpretation of Measurement Results of the Potential Difference in Lake Baikal

A model is proposed in which the electrical voltage measured between the electrodes in Lake Baikal is a consequence of two effects: electrochemical processes near the electrodes and a positive charge current flowing through the lake. The electrochemical component of the voltage in the case of lead electrodes arises due to the difference in concentrations of carbonate anion— $${\text{CO}}_{3}^{{2 - }}$$ at different depths. In the case of the use of chlorine-silver electrodes, only the effect of the positive charge current flowing through the lake is measured. We proposed an interpretation of an increase of electrical voltage registered in Lake Baikal during an earthquake in August 2008. The reason for the increase in voltage is the release of positively charged hydrogen-containing gases from the Earth’s interior.

Configurational electronic states in layered transition metal dichalcogenides

Mesoscopic irregularly ordered and even amorphous self-assembled electronic structures were recently reported in two-dimensional metallic dichalcogenides (TMDs), created and manipulated with short light pulses or by charge injection. Apart from promising new all-electronic memory devices, such states are of great fundamental importance, since such aperiodic states cannot be described in terms of conventional charge-density-wave (CDW) physics. In this paper, we address the problem of metastable mesoscopic configurational charge ordering in TMDs with a sparsely filled charged lattice gas model in which electrons are subject only to screened Coulomb repulsion. The model correctly predicts commensurate CDW states corresponding to different TMDs at magic filling fractions Doping away from results either in multiple near-degenerate configurational states, or an amorphous state at the correct density observed by scanning tunnelling microscopy. Quantum fluctuations between degenerate states predict a quantum charge liquid at low temperatures, revealing a new generalized viewpoint on both regular, irregular and amorphous charge ordering in transition metal dichalcogenides.

Dynamic performance analysis and optimization of dish solar Stirling engine based on a modified theoretical model

A modified theoretical model of dish solar Stirling engine was developed based on a Stirling cycle operating with finite shaft rotating speed and the energy balance equations at hot and cold ends. The convergence of solar receiver temperature and charged gas heat releasing temperature represent the stabilization of solar receiver and Stirling engine respectively, thus, to guarantee a steady operation of the overall system. Impacts of meteorological condition, operational parameter of Stirling engine on system performance were investigated and analyzed systematically. Results indicate that higher solar flux intensity improves system performance while wind deteriorates the system performance. With the input solar energy specified, optimal charged gas mass in Stirling engine exists corresponding to the maximal power output. More effective heater, regenerator and cooler contribute to better optimal system performance. Meanwhile, the charged gas mass optimized under the daily average solar flux intensity achieves the maximal mechanical work in a day with less computation. The maximal theoretical peak power output of 25 kW and overall efficiency of 44% are obtained as high performance heat exchangers are adopted and charged gas mass is optimized.

Generation of Acoustic Disturbances by a Moving Charged Gas Suspension

Consideration is given to the dynamics of a charged gas suspension in an external electric field. The process of generation of acoustic waves in the carrier medium on instantaneous switch-on of the external electric field setting the dispersed phase in motion is described. The influence of the size of particles and of the volume content of the dispersed phase on the intensity of acoustic disturbance is considered.

The process of deposition of a charged polydisperse gas suspension on the surface of the plate in an electric field

The process of deposition of a charged polydisperse gas suspension on the surface of the plate in an electric field

Process of the Deposition of Charged Polydisperse Gas Suspension on the Plate Surface in an Electrical Field

The process of powder sputtering onto a flat surface in an electric field is described on the basis of the numerical solution of a system of equations of the dynamics of a polydisperse gas suspension. The model includes equations for the motion of the carrier and disperse phases under the action of the aerodynamic friction force and the Coulomb force, taking into account the interphase exchange of momentum and energy. The system is solved by the explicit predictor–corrector method with splitting over the spatial directions and the nonlinear correction scheme. The numerical model is used to obtain the velocity and density fields of the gas suspension in the interelectrode space and on the surface of the target electrode.

Numerical simulation of vortex structures in the spraying of electrically charged gas suspension on a plate

Based on the numerical solution of polydisperse gas suspension dynamics system of equations, the process of powder spraying on a plane surface in an electric field is described. The model includes motion equations of the carrier medium and disperse phase fractions under aerodynamic friction and Coulomb forces action taking into account interfacial exchange of pulse and energy. The system solves by an explicit predictor-corrector method with splitting on the spatial directions and the non-linear correction scheme. The numerical model is applied to gas suspension speed and density fields receiving in interelectrode space and on target electrode surface. The system of equations was written in the generalized curvilinear coordinates: the physical region of a current in variables (x, y) was written in a canonical computational region in variables (ξ,η) and was solved by an explicit second-order Mac-Cormack method. The Poisson equation for the electric field potential was written in the generalized coordinates and was solved by finite difference method with the use of the iterative Seidel scheme on a gas-dynamic computational mesh.

Atmospheric-pressure plasma irradiation can disrupt tobacco mosaic virus particles and RNAs to inactivate their infectivity.

Low-temperature atmospheric-pressure air plasma is a source of charged and neutral gas species. In this study, N-carrying tobacco plants were inoculated with plasma irradiated and non-irradiated tobacco mosaic virus (TMV) solution, resulting in necrotic local lesions on non-irradiated, but not on irradiated, TMV-inoculated leaves. Virus particles were disrupted by plasma irradiation in an exposure-dependent manner, but the viral coat protein subunit was not. TMV RNA was also fragmented in a time-dependent manner. These results indicate that plasma irradiation of TMV can collapse viral particles to the subunit level, degrading TMV RNA and thereby leading to a loss of infectivity.

On the Passage of a Shock Wave through a Layer of Charged Gas

A class of exact solutions of the ideal electrohydrodynamics equations is presented. These solutions describe the propagation of a plane shock wave along a static background with decreasing density in the presence of gravity and longitudinal electric fields. This class of solutions contains an arbitrary function of the Lagrangian variable which makes it possible to consider many physically different cases.

Modeling of networks and globules of charged domain walls observed in pump and pulse induced states

Experiments on optical and STM injection of carriers in layered MX2 materials revealed the formation of nanoscale patterns with networks and globules of domain walls. This is thought to be responsible for the metallization transition of the Mott insulator and for stabilization of a “hidden” state. In response, here we present studies of the classical charged lattice gas model emulating the superlattice of polarons ubiquitous to the material of choice 1T − TaS2. The injection pulse was simulated by introducing a small random concentration of voids which subsequent evolution was followed by means of Monte Carlo cooling. Below the detected phase transition, the voids gradually coalesce into domain walls forming locally connected globules and then the global network leading to a mosaic fragmentation into domains with different degenerate ground states. The obtained patterns closely resemble the experimental STM visualizations. The surprising aggregation of charged voids is understood by fractionalization of their charges across the walls’ lines.

Early-stage aggregation in three-dimensional charged granular gas.

Neutral grains made of the same dielectric material can attain considerable charges due to collisions and generate long-range interactions. We perform molecular dynamic simulations in three dimensions for a dilute, freely cooling granular gas of viscoelastic particles that exchange charges during collisions. As compared to the case of clustering of viscoelastic particles solely due to dissipation, we find that the electrostatic interactions due to collisional charging alter the characteristic size, morphology, and growth rate of the clusters. The average cluster size grows with time as a power law, whose exponent is relatively larger in the charged gas than the neutral case. The growth of the average cluster size is found to be independent of the ratio of characteristic Coulomb to kinetic energy, or equivalently, of the typical Bjerrum length. However, this ratio alters the crossover time of the growth. Both simulations and mean-field calculations based on Smoluchowski's equation suggest that a suppression of particle diffusion due to the electrostatic interactions helps in the aggregation process.

Anisotropic equation of state of charged and neutral vector boson gases in a constant magnetic field: Astrophysical implications

We obtain the pressures and equations of state (EoS) of charged and neutral vector boson gases in a constant magnetic field. The axial symmetry imposed to the system by the field splits the pressures in the parallel and perpendicular directions along the magnetic axis, and this leads to anisotropic equations of state. The values of pressures and energy densities are in the order of those of Fermi gases in compact objects. This opens the possibility to the existence of magnetized boson stars. Under certain conditions, the perpendicular pressure might be negative imposing a bound to the stability of the star. Other implications of negative pressures are also discussed.

Charged fermion gas polarization in strong magnetic fields

We study the polarization of a charged fermion gas in the presence of intense magnetic fields by finding an exact numerical expression for the gas number density. We compute the polarization as a function of the magnetic field, chemical potential, and temperature and compare them with approximate analytical results. We find that the analytical approximations are in agreement with the numerical results only in the asymptotic limit of these parameters.

Finite Size Correction to The Thermo-Magnetic Properties of Charged Bose Gas

We consider the finite size effect on thermo-magnetic properties of charged Bose gases confined in a quasi two-dimentsional potential. A modified semiclassical approach is used, taking into account the finite size correction to guarantee an accurate density of states. The charged spinless Bose gas shows diamagnetic behavior. Temperature dependent magnetization is indicated for the investigated system that condense at a resistive critical temperature in accordance with the applied magnetic field.