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In this paper, the dust acoustic wave is studied in conditions where the dust temperature is not constant. This model includes negatively charged dust particles and thermal ions. The reductive perturbation technique is used and the new point in this study is the nonuniformity of the plasma temperature. The nonconstancy of the temperature is entered as a first-order perturbation in the calculations, and finally the modified Korteweg–de Vries (mKdV) equation is derived. The solution of the modified KdV equation clarifies the change in soliton shape of the wave when it moves in the perturbation plasma. We show how the soliton wave undergoes deformation and amplitude reduction during propagation when it encounters a region with a different temperature. The output of this research can be effective to better understand the wave behavior in a real plasma with nonuniform temperature. [ABSTRACT FROM AUTHOR]

In this paper, the role of dust grain's gravitational force on the nonlinear dust‐acoustic oscillations in non‐Maxwellian dusty plasma is analyzed. It is shown that increasing the number of non‐thermal ions causes the diminution of the electrostatic potential's amplitude and a reduction in the number of oscillations introduced by the gravitational force. We have also found that reducing the size of the dust grain induces qualitatively the same effects as an increase in the number of non‐thermal ions and when the gravitational force is considered, the electric charge exhibits oscillatory profile and becomes less negative far away from the origin. This result may be interesting in the study of astrophysical plasmas where the electromagnetic force is smaller than the gravitational one such as in the Halley Comet. [ABSTRACT FROM AUTHOR]

In this paper, the Crank-Nicholson method is applied to solve the one-dimensional nonlinear Burgers' equation in warm, dusty plasmas with dust charge variation. After obtaining numerical results, a thorough analysis is conducted and compared against analytical solutions. On the basis of the comparison, it is evident that the numerical results obtained from the analysis are in good agreement with the analytical solution. The error between the analytical and numerical solutions of the Burgers' equation is calculated by two error norms, namely L2 and L∞. A Von-Neumann stability analysis is performed on the present method, and it is found to be unconditionally stable according to the Von-Neumann analysis. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of compressibility on the internal wave modes and the density gradient-driven Rayleigh–Taylor (R–T) instability in magnetized strongly coupled dusty plasmas. The dusty magnetohydrodynamic model is formulated for compressible fluids, accounting for the effects of weakly coupled electrons/ions and strongly coupled dust particles under the influence of the gravitational field. The effect of the magnetic field on the dust dynamics has been incorporated through the magnetic force on the electrons and ions in quasineutral dusty plasmas. A dispersion relation of the R–T instability has been derived which has been modified because of the compressibility effect, dust acoustic wave speed and viscoelastic coefficients. The shear Alfvén and compressional viscoelastic wave modes become coupled in the dispersion characteristics. The modified R–T instability criterion is derived in terms of the Alfvén speed, viscoelastic effects and dust grain parameters. The graphical illustrations show that the growth rate of R–T instability has been suppressed due to compressibility, viscoelastic coefficients and dust acoustic speed. The results are useful to discuss the development of R–T instability in magnetized astrophysical dusty plasmas. [ABSTRACT FROM AUTHOR]

The center of this paper is to establish the generalized variational structure (GVS) of the (3 + 1) -dimensional Zakharov–Kuznetsov–Burgers equation (ZKBe) by taking advantage of the Semi-inverse method (SIM). Two different GVSs are extracted and the derivation process is presented in detail. The extracted GVSs reveal the energy conservation law and can offer some new insights on the study of the variational method. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive exploration of shock waves in a dusty plasma, incorporating the dynamics of inertial dust and ions with Maxwellian distributed electrons. By deriving the Korteweg-de Vries-Burgers (KdV-B) equation and by using its standard solution we analyze the characteristics of the shock front under varying parameters. Furthermore, we conduct a phase plane analysis to elucidate the system's behavior and dynamics by tuning in the parameters that provide various types of perturbation in the system. The investigation sheds light on the intricate behavior of shock waves in dusty plasmas and contributes valuable insights to the understanding of plasma dynamics. [ABSTRACT FROM AUTHOR]

A theoretical investigation is presented to explain the formation and characteristics of relaxed equilibrium structures in a three-component dusty plasma within Saturn's atmosphere, composed of negatively charged dust particles, electrons, and ions. The Quadruple Beltrami equation is derived by utilizing the vortex dynamic equations along with the current density. Solutions for the higher Beltrami states are obtained in two different modes, a simple rectangular geometry and a coplanar rectangular geometry, to explore the characteristics of relaxed structures within the Saturn magnetosphere and its rings. The solutions are depicted through some plots by varying the Beltrami parameters and the densities of the plasma species. It is observed that only paramagnetic structures are formed in the coplanar geometry, while variations in the Beltrami parameters and plasma species densities significantly affect the magnetic characteristics of the relaxed structures in a simple rectangular geometry. This paper will provide an important contribution to understand the atmospheric vortical structures developed in different astronomical bodies that have double or more than double configurations, such as Saturn's rings, Jupiter magnetosphere, Uranus, Neptune, etc. [ABSTRACT FROM AUTHOR]

Since the first automatic missions to the Moon, the activity of dust particles from atmosphereless bodies has been recorded. Since then, a lot of theoretical and experimental studies of this effect have been carried out, but at present there is no clear understanding of the influence of external actions on the dynamics of this phenomenon. This paper presents the results of experiments to determine the effect of hard UV radiation on the activity of dust particles, which makes a significant contribution to particle dynamics. The result of determining the conditions for particle removal from the surface is in accordance with theoretical calculations. [ABSTRACT FROM AUTHOR]

Cellulose is an abundant natural polymer and is thus promising for enforcing biobased plastics. A broader application of cellulose fibers as a filler in polymer composites is limited because of their hydrophilicity and hygroscopicity. The recent scientific literature on plasma methods for the hydrophobization of cellulose materials is reviewed and critically evaluated. All authors focused on the application of plasmas sustained in fluorine or silicon-containing gases, particularly tetrafluoromethane, and hexamethyldisiloxane. The cellulose materials should be pre-treated with another plasma (typically oxygen) for better adhesion of the silicon-containing hydrophobic coating. In contrast, deposition of fluorine-containing coatings does not require pre-treatment, which is explained by mild etching of the cellulose upon treatment with F atoms and ions. The discrepancy between the results reported by different authors is explained by details in the gas phase and surface kinetics, including the heating of samples due to exothermic surface reactions, desorption of water vapor, competition between etching and deposition, the influence of plasma radiation, and formation of dusty plasma. Scientific and technological challenges are highlighted, and the directions for further research are provided. [ABSTRACT FROM AUTHOR]

A first theoretical attempt is made to understand the characteristics of dust acoustic shock waves (DASWs) in a polarized electron-depleted plasma with a mixed nonextensive high energy–tail ion distribution and to examine the impact of the generalized nonthermal polarization force on DASWs in an electron-depleted dusty plasma. First, a short numerical investigation illustrating the behavior of the mixed nonextensive high energy–tail (or Cairns–Tsallis) ion distribution and the domain of validity of its two parameters (q and α) is carried out. Next, the generalized nonthermal polarization acting on dust grain in electron-depleted dusty plasma is determined within the context of Tsallis' statistical mechanics. The behavior of this generalized polarization force is significantly affected by the nonextensive character of the nonthermal ions. Specifically, we have shown that, for both space and experimental dusty plasmas, the magnitude of the polarization force (in the case where − 1 < q < 1) decreases as the nonextensivity of the nonthermal ions becomes significant. As an application, we have analyzed the changes caused by the nonthermal nonextensive polarization force on the main characteristics of DASW (viz. phase velocity, polarity, amplitude, width, etc.). Numerical results showed that our plasma model supports rarefactive and compressive DASWs that are significantly affected by the effects of nonthermal ion nonextensivity and polarization force. In particular, we have shown that for large values of the nonthermal parameter α , the increase in q allows the transition from rarefactive to compressive DASW structures. The present theoretical investigation is helpful to fully understand electrostatic disturbances in space and experimental dusty plasmas. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effect of different amounts of filler on concrete properties. An experimental approach has made it possible to develop a construction product made from limestone dust, which is considered waste. This paper presents an experimental study on the prospects of using a mixture of waste limestone powder for the manufacture of an economical and lightweight composite as a building material. This paper also presents the results of research on the possibility of using limestone dust as an aggregate in the production of concrete with lightweight aggregates. In this way, different amounts of limestone dust were used. Tests were conducted on concrete to replace 30, 50, and 70% by weight of coarse aggregate. The mechanical properties of concrete mixtures with high proportions of limestone dust were examined. The achieved compressive strength, flexural strength, and unit weight correspond to current international standards. [ABSTRACT FROM AUTHOR]

The use of heat transfers in heat exchangers, nuclear cooling, solar collectors, and electrical devices is crucial nowadays. Hybrid nanofluid can be used in these applications to get the best results because it encourages efficient heat transmission compared to conventional fluid. The effect of radiation and an unsteady Carreau hybrid fluid in addition to non-Fourier heat flux over a shrinking sheet is discussed in this paper. Using similarity transformations, the newly developed system of partial differential equations (PDEs) is converted into a set of ordinary differential equations (ODEs), that are next numerically addressed by utilizing shooting approach and the Runge–Kutta (RK) method. Tables and graphs are used to present utilizing the computational findings for nondimensional temperature, velocity, heat transfer rate, and friction between fluid and hybrid nanoparticles. Additionally, for certain physical factors, the physical quantities in numerical values were also presented (such as the friction factor and local Nusselt number). We made a restricted case comparison between the current findings and the body of prior research. Our finding confirms that the temperature profile is strengthened by the heat generation parameter and the effect of radiation. The porosity parameter decelerates the momentum boundary layer thickness near the plate. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the behavior of dust ion acoustic solitary waves (DIASWs) with arbitrary amplitudes in a magnetized anisotropic dusty plasma that includes inertial hot ion fluid, electrons following a Kappa distribution, and negatively charged dust particles in the background. An ambient magnetic field aligns with the x-direction, while the wave propagation occurs obliquely to the ambient magnetic field. In the linear regime, two distinct modes, namely fast and slow modes, are observed. We employ the Sagdeev pseudo-potential method to analyze the fundamental properties of arbitrary amplitude DIASWs. Additionally, we examine how various physical parameters influence the existence and characteristics of symmetric planar dust ion acoustic solitary structures (DIASs). The characteristics of the solitary structures are greatly influenced by the dust concentration, the electrons superthermality (spectral) index, the obliquity parameter, the magnetic field, the parallel ion pressure and the perpendicular ion pressure. The results show that the amplitude and width of both compressive and rarefactive DIASWs are sensitive to the degree of electron superthermality and dust concentration. Additionally, it is shown that the propagation features of DIASWs are highly affected by the parallel component of ion pressure as compared to perpendicular component of ion pressure. [ABSTRACT FROM AUTHOR]

When the hypersonic vehicle is flying, the plasma in the area near the stagnation point of the front end of the vehicle can be approximately seen as the fully ionized dusty plasma. Due to the existence of dust particles, dusty plasma affects the communication quality of the hypersonic vehicle. In this paper, the general Boltzmann equation applicable to dusty plasmas containing electrons and the Fokker–Planck–Landau collision model are combined to derive a general formula for the electron distribution function of fully ionized dusty plasmas. Considering the contribution of the collision effect and charging effect to the dispersion relationship of fully ionized dusty plasma, the dielectric constant of fully ionized dusty plasma under an external magnetic field is solved. The Wentzel–Kramers–Brillouin method is used to calculate the attenuation coefficient (α) of the THz wave in fully ionized dusty plasma, and the influence of the external magnetic field strength and other dusty plasma parameters on the attenuation characteristics of the THz circularly polarized wave is analyzed. The research results show that the α of the THz left-hand circularly polarized wave decreases with the increase in the external magnetic field strength, while the α of the THz right-hand circularly polarized wave increases. In addition, increasing the dust particle radius, dust particle density, and electron density in a certain frequency range can increase the α of the THz circularly polarized waves. These research results provide theoretical guidance for the exploration of the interaction mechanism between the THz waves and fully ionized dusty plasma. [ABSTRACT FROM AUTHOR]

The exosphere of Mercury, which has much in common with the exosphere of the Moon, can also contain suspended dust particles, which, under the action of intense solar radiation, acquire positive charges and form one of the components of the dusty plasma system. In addition to dust particles, there are photoelectrons above the planet surface, formed as a result of interaction of solar radiation with the planet surface, as well as with suspended dust particles. Mercury, unlike the Moon, has its own magnetosphere, which affects the parameters of dusty plasma system. The dusty plasma parameters near the Mercury surface can vary depending on the distance from the planet to the Sun, which considerably changes when the planet moves along the elongated orbit, and also depending on the localization of the region under consideration on the planet surface. Thus, near the magnetic poles, the solar wind can reach the planet surface, which must be taken into account when determining the plasma parameters. Far from the magnetic poles, the effect of the solar wind can be neglected. In the dusty plasma near the surface of Mercury, one can expect the development of linear and nonlinear wave processes. In this paper, nonlinear waves are considered, namely, dust acoustic solitons and nonlinear periodic waves. The profiles of potentials of high-amplitude solitons and nonlinear periodic waves are obtained, as well as the soliton amplitudes as functions of the altitude above the planet surface and soliton velocity. [ABSTRACT FROM AUTHOR]

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Ladle slag is a byproduct formed during the ladle refining stage of steel making. It is a dusty material that has been considered industrial waste. Technical advancements towards a sustainable industry led to the development of different applications for ladle slag. Depending on the processing methods during the steel slag production and the weathering of the slag post‐production, the elemental composition of the steel slag largely varies. Owing to this, its characteristics cannot be generalized and specific applications depending on the sources are developed. It is generally used in construction materials, soil rejuvenation, and CO2 capture. This paper reviews the production process, the mineralogical and morphological properties, stabilization techniques, and the applications of ladle furnace (LF) slag. One of the prime focuses of waste remediation and sustainable industry is to find meaningful ways to turn waste into products. In this respect, a comprehensive review of the properties of LF slag and its current application will help provide a framework for the development of future sustainability goals. With increased slag usage, the ladle refining process of steelmaking can be turned into a more carbon‐neutral process. [ABSTRACT FROM AUTHOR]

This paper presents a new approach to determining the dimensions of particles that can be lifted to a coma by the sublimation flux of water ice. Due to the diverse colour of the cometary surfaces, in the presented calculations we take into account the influence of the reflectance coefficient (hemispherical albedo) on the size of particles lifted from the surface of the nucleus. A Cary 5000 spectrometer was used to measure hemispherical albedo. Spectroscopic measurements used dust particles that consisted of pure silicate or were a mixture of pure silicate and organic compounds such as charcoal, soot, and ash. In addition, these admixtures acted as a means of darkening the tested sample. Depending on the colour of the sample and the wavelength, the measured value of hemispherical albedo oscillated in the range from 4.93 per cent to 48.65 per cent. A thermodynamic model of cometary matter emission was developed based on the results of hemispherical albedo measurements. The performed numerical simulations show that the temperature decreases with the increase of the hemispherical albedo, which translates into the sublimation flux and the dynamics of the dust-ice particles present on the surface of the cometary nucleus. Taking into account the extreme values of the hemispherical albedo, the differences in the size of particles carried away from the surface of the nucleus are in the order of centimeters. [ABSTRACT FROM AUTHOR]

In this paper, we have presented our investigation on the characteristic of nonlinear dust acoustic waves (DAWs) propagating in an inhomogeneous collisionless magnetized dusty plasma (MDP). In this problem, we have considered a collisionless plasma consisting of nonthermal ions, non-extensive electrons and negatively charged dust grains. Using the reductive perturbation theory (RPT) we have derived the modified Zakharov-Kuznetsov (m-ZK) equation. The solution of m-ZK equation indicates the nonlinear characteristics of the DASWs in plasma. Our investigation also predicts how the amplitudes of nonlinear DASWs are significantly modified due to the influence of magnetic field, non-extensive electrons and inhomogeneity parameters in plasma. The results obtained in this investigation may be useful for understanding the propagation characteristics and modification of structures of nonlinear waves in both laboratory and astrophysical plasmas. [ABSTRACT FROM AUTHOR]

Dusty plasmas are electrically quasi-neutral media that, along with electrons, ions, neutral gas, radiation, and electric and/or magnetic fields, also contain solid or liquid particles with sizes ranging from a few nanometers to a few micrometers. These media can be found in many natural environments as well as in various laboratory setups and industrial applications. As a separate branch of plasma physics, the field of dusty plasma physics was born in the beginning of 1990s at the intersection of the interests of the communities investigating astrophysical and technological plasmas. An additional boost to the development of the field was given by the discovery of plasma crystals leading to a series of microgravity experiments of which the purpose was to investigate generic phenomena in condensed matter physics using strongly coupled complex (dusty) plasmas as model systems. Finally, the field has gained an increasing amount of attention due to its inevitable connection to the development of novel applications ranging from the synthesis of functional nanoparticles to nuclear fusion and from particle sensing and diagnostics to nano-contamination control. The purpose of the present perspectives paper is to identify promising new developments and research directions for the field. As such, dusty plasmas are considered in their entire variety: from classical low-pressure noble-gas dusty discharges to atmospheric pressure plasmas with aerosols and from rarefied astrophysical plasmas to dense plasmas in nuclear fusion devices. Both fundamental and application aspects are covered. [ABSTRACT FROM AUTHOR]

The diagnostic of magnetized radio frequency complex plasma via probing techniques and spectroscopy is challenging. However, a self-excited dust ion acoustic waves (DIAWs) have been observed employing laser scattering. Inspired by the current high enthusiasm for the theoretical description of complex plasma, we study the propagation of DIAWs in a three-dimensional collisional and magnetized dusty plasma medium. We consider the fluid model for dust and ion particles, while we neglect the inertia of electrons considering the Boltzmann distribution. A linear dispersion relation is obtained and a nonlinear modified Zakharov–Kuznetsov equation is derived utilizing the reductive perturbation technique. The effects of ion-neutral and dust-neutral collisions on the dynamics of the nonlinear DIAWs are considered. The phase portrait analysis and numerical illustration of a rarefactive DIA cnoidal waves and solitons are also presented. Our findings agree with experimental observations by Choudhary M, Bergert R, Mitic S, and Thomas MH. [Influence of external magnetic field on dust acoustic waves in a capacitive rf discharge. Contrib Plasma Phys. 2020;60:e201900115] as the growth of nonlinear periodic waves is recorded when the magnetic field is roughly 0.05 T and vanishes when the magnetic field is close to 0.1 T. Moreover, the model reveals that the electrostatic cnoidal and soliton waves propagate with low frequencies up to 140 Hz. [ABSTRACT FROM AUTHOR]

The existence and propagation of dust acoustic waves in quantum four-component plasma are investigated by employing Sagdeev pseudo-potential. The plasma under consideration consists of both quantum electrons and ions beside negative and positive dust particulates. The general determining equation of the Sagdeev pseudo-potential is obtained, and it is found that the equation is very difficult to integrate. Due to the complexity involved in the structure of Sagdeev potential, this equation can only be solved in some limiting cases, such as semi-classical limit and small amplitude approximation. Our findings support the existence of compressive, rarefactive solitary waves and double layers in our plasma system. The influence of the relevant plasma parameters on the existence and profile of the obtained quantum nonlinear waves has been studied. The implications of the obtained results have wide relevance in the study of space and laboratory quantum dusty plasmas situations such as Jupiter's magnetosphere, upper and lower mesosphere, and comet tails, as well as in condensed matter systems. [ABSTRACT FROM AUTHOR]

A theoretical investigation has been made to explore the behavior of nonplanar (cylindrical and spherical) electrostatic shock waves in a dusty plasma system that consists of arbitarily charged dust particles, negatively charged heavy ions following Cairn's distribution, positively charged ions with two different temperatures, and nonextensive electrons. The reductive perturbation technique is used to derive a modified Burgers equation analytically. Analytical analysis shows that the characteristics of the nonplanar shock waves, including their polarity, amplitude, width, and phase speed, undergo significant alterations due to factors such as the charges on dust particles, the number density of particles, the temperatures of heavy and light ions, nonextensive electron behavior, and dust kinematic viscosity. Furthermore, this study found shock structures with either a positive or negative potential, depending on the critical value of the proportion of ions to the density of dust particles. The findings maybe useful in understanding the characteristics of shock waves both in space plasma environments and laboratory plasmas. [ABSTRACT FROM AUTHOR]

A theoretical investigation of the phase-mixing phenomenon of Langmuir oscillations (LOs) in a multi-component dusty plasma is presented. The plasma under study is a four-component plasma consisting of electrons, positrons, singly ionised positive ions and positive (or negative) polarity dust grains. The massive dust grains are assumed to form a fixed charge neutralising background, while the electrons, positrons and ions are considered to take part in the wave dynamics. A simple perturbative analysis of the governing fluid-Maxwell's equations leads us to an approximate relation for phase-mixing time of LOs, improving some earlier existing results. It is revealed that even though the dust grains remain motionless in the background, they still have significant impact on the phase-mixing process of LOs in such plasmas. It is found that the nature of the charge on the dust grains and the equilibrium dust density profoundly affect the phase-mixing time. The results of this investigation is expected to have relevance in space-plasma environments. [ABSTRACT FROM AUTHOR]

The effect of dust grain pressure on the head‐on collision of two dust‐acoustic solitary waves in non‐magnetized, collisionless, and strongly coupled dust plasma has been investigated [J. Plasma Phys. (2020), 86, 905,860,111]. In this paper, the model is augmented by incorporating the ion drag force on dust grains. By way of the extended perturbation method of Poincaré‐Lighthill‐Kuo, Korteweg‐de Vries equations are derived. The wave characteristics along with the phase shifts after the head‐on collision are analytically established and numerically assessed. It revealed a non‐negligible decrease in the wave amplitude and the phase shift. [ABSTRACT FROM AUTHOR]

In this paper, we present experimental observation of the transition of a 2D dust crystal to a non-equilibrium solid–liquid phase coexistence state. The experiments have been carried out in an L-shaped dusty plasma experimental device in a DC glow discharge argon plasma environment. Initially, a monolayer crystalline structure is formed, which is later transformed to a two-phase coexistence state using the background neutral pressure as a control parameter. Self-excited horizontal oscillations are found in the center of the monolayer prior to the appearance of the coexistence state. It is observed that a molten center coexists with a solid periphery. Various structural, thermodynamic, and dynamical quantities are used to characterize the phase state. The surface tension at the solid–liquid circular interface is also determined. A detailed parametric study is made to delineate the existence region of such a state. It is found that melting caused at the core is due to the onset of a localized Schweigert instability in the presence of a few stray particles beneath the top layer in that region. [ABSTRACT FROM AUTHOR]

In this paper, non-linear propagation of oscillatory and monotonous DIA shocks in dusty plasma with dust charge fluctuations and small isothermal deviation of electrons is considered. The modified-Korteweg-de Vries–Burger (m-KdVB) equation can be derived by using the reductive perturbation (R-P) method. The variational principle and the conservation laws of the m-KdVB equation are constructed by introducing two special functions. A nonlinear self-adjoint classification of the m-KdVB equation is presented. Based on the Ibragimov's theorem, conservation laws for m-KdVB equation are established. We also study the m-KdVB equations by improved tan ψ (χ) 2 -expansion method. Abundant dark, singular and periodic optical solitons solutions of the model are constructed. Furthermore, additional graphical simulations were performed using mathematica to see the behavior of these solutions. With the help of bifurcation theory of planar dynamical systems, we study bifurcation and phase portrait analysis of traveling wave solution of the m-KdVB equation. [ABSTRACT FROM AUTHOR]

Intermediate-luminosity red transients (ILRTs) are a class of observed transient posited to arise from the production of an electron-capture supernova from a super-asymptotic giant branch star within a dusty cocoon. In this paper, we present a systematic analysis of narrow Na  i D absorption as a means of probing the circumstellar environment of these events. We find a wide diversity of evolution in ILRTs in terms of line strength, time-scale, and shape. We present a simple toy model designed to predict this evolution as arising from ejecta from a central supernova passing through a circumstellar environment wherein Na  ii is recombining to Na  i over time. We find that while our toy model can qualitatively explain the evolution of a number of ILRTs, the majority of our sample undergoes evolution more complex than predicted. The success of using the Na  i D doublet as a diagnostic tool for studying circumstellar material will rely on the availability of regular high-resolution spectral observations of multiple ILRTs, and more detailed spectral modelling will be required to produce models capable of explaining the diverse range of behaviours exhibited by ILRTs. In addition, the strength of the Na  i D absorption feature has been used as a means of estimating the extinction of sources, and we suggest that the variability visible in ILRTs would prevent such methods from being used for this class of transient, and any others showing evidence of variability. [ABSTRACT FROM AUTHOR]

The International Conference on "Strongly Coupled Coulomb Systems" (SCCS) was held in Görlitz, Germany from July 24-29, 2022. The conference, organized by the Center for Advanced Systems Understanding (CASUS), brought together researchers from various disciplines to discuss research achievements and ideas related to plasma-liquid and condensed-matter systems dominated by strong Coulomb interactions. The conference covered a wide range of topics, including confined and mesoscopic Coulomb systems, astrophysical plasmas, dense hydrogen, dusty plasmas, and more. The conference was held in a hybrid format, allowing both in-person and virtual participation. Over 100 researchers from four continents participated, and the proceedings of the conference have been published in Contributions to Plasma Physics. [Extracted from the article]

The existence and propagating characteristics of small amplitude dust-ion-acoustic (DIA) Korteweg-de Vries (KdV) and modified KdV solitons in a three component magnetized plasma composed of positive inertial ions with pressure variation, noninertial electrons and negative charged immobile dust grains are theoretically and numerically investigated when the electrons obey a q-nonextensive velocity distribution. Utilizing the reductive perturbation method, to derive KdV and modified KdV equations and obtain the DIA soliton solutions along with the corresponding small amplitude potentials. This study shows that there are compressive and/or rarefactive solitons and no soliton at all, due to the parametric dependency on the first-order nonlinear coefficient through the number density of positive ions and negative dust grains and the electron nonextensivity. The coexistence of compressive and rarefactive solitons appears by raising the measure of nonlinearity coefficient to the second-order using the modified KdV equation. The properties such as speed, amplitude, width etc. of the propagating soliton are numerically discussed. [ABSTRACT FROM AUTHOR]

Particle contamination due to plasma processing motivates the design of a method of electrically lifting particles in a time interval after a plasma's power is turned off. Small solid dust particles have electric charges that are not frozen until a late stage of the plasma afterglow. Beyond that time, before they fall to a surface below and cause defects, particles can be lifted in a controlled manner by applying an appropriate direct-current (DC) electric field, as we demonstrate experimentally. A few milliseconds after an argon plasma's capacitively coupled radio-frequency power is switched off, a vertical DC electric field is applied. Thereafter, video imaging shows that the falling of the particles is slowed or stopped altogether, depending on the magnitude of the upward electric force. [ABSTRACT FROM AUTHOR]

The article focuses on the nature of gravity and inertia. Topics discussed include the transmutation effect of low energy nuclear reaction (LENR) discovered by Professor Alberto Carpinteri and his team at the University of Torino, the U.S. Patent 10,144,53 awarded to inventor Salvatore Pais in 2018, under the title "Craft Using an Inertial Mass Reduction Device," and transient electrogravity device for triangular antigravity vehicle, from Pais' St. Clair patent.

The first true common volume observations of the PMSE source region with 4 radars are presented in this paper. Radar frequencies of 8, 56, 224, and 930 MHz are used in this study. Three days of experimental observations at EISCAT are presented. Numerical simulations of mesospheric dusty/ice plasma associated with the observed radar frequencies are presented. The effect of neutral air turbulence on the generation and strength of plasma density perturbations associated with PMSE using four radar frequencies and in the presence of various dust parameters is investigated. Using the model it is shown that the well‐known neutral air turbulence in the presence of heavy dust particles and neutral air turbulence combined with dust density (dusty turbulence) can largely explain the observed radar cross‐section at four radar frequencies. The effect of neutral air turbulence amplitude along with dust charging and diffusion in the presence of various dust parameters is investigated using the computational model. Specifically, the response of diffusion to charging time scales, plasma density fluctuation amplitude and background dusty plasma parameters are discussed. Several key parameters in the dusty plasma responsible for the PMSE observations are determined. Qualitative comparison of radar echo strength at 4 frequencies with numerical results is provided. Unlike the previous studies that required large dust particles of 20 nm for PMSE formation, the present work demonstrates the possibility of small dust particles to explain the experimental observations. Key Points: The first simultaneous four radar frequency observation of the PMSE is presentedThe computational results and observations validate the fossil theory proposed to 14 produce the PMSEThe effect of initial turbulence amplitude along with dust charging and diffusion 16 in the presence of various dust parameters is investigated for the first time [ABSTRACT FROM AUTHOR]

When a high-speed spacecraft returns to the atmosphere, a plasma sheath is formed on its surface. This causes electromagnetic waves to be reflected and absorbed. In this paper, a single-layer medium matrix transport model is used to derive expressions for the reflectivity, transmittance and attenuation values of electromagnetic waves. The electron density distribution is also modelled and the effects of electron density, plasma thickness, particle collision frequency, and magnetic field strength on the reflectivity as well as the transmittance of electromagnetic waves are discussed visually using three-dimensional images. Finally, the reflectivity and transmittance of electromagnetic waves propagating in a dust-free plasma are analyzed, with emphasis on comparing the effects of different media on the reflectivity and transmittance of electromagnetic waves. In summary, the relevant research can provide some theoretical references for propagation science. [ABSTRACT FROM AUTHOR]

This is the second paper in the series about the design and operation of LENR reactors, to be followed by Part 5C on the same subject. While in Part 5A we mainly discussed the reactors based on electrolysis that were at the center of research for decades, a new field of reactors based on dusty plasma was also discussed. We move into a new area in Part 5B: LENR reactors based on quasi-particles. Though plasmon polaritons and condensed plasmoids were frequently mentioned in all previous parts, we shall move towards their practical applications. First the landscape of mainstream transient plasma research is shown. There the streamers of corona and spark discharges are known to produce heavy negative quasi-particles. However, they have never been tested for catalytic nuclear fusion, just as chemical catalysts. We shall review spark related research, as this area is shown to induce fusion effects. Most of the results have been published in peer-reviewed journals, like Fusion Technology. The most important results have come from the papers of Matsumoto, Karabut and Dufour. The most important patents were granted to Shoulders. These results were published mainly in the 1990s, the "golden age" of LENR research. Based on these results and insights, we move back a hundred years, to the research of Tesla. Judging by the shape of his discharge tubes, it is plausible that Tesla had a practical application of the results published 100 years later. In Part 5C, inventions after the 1930s will be analyzed. [ABSTRACT FROM AUTHOR]

Aiming to delineate the physical framework of blazars, we present an effective method to estimate four important parameters based on the idea proposed by Becker & Kafatos, including the upper limit of central black hole mass M, the Doppler factor δ, the distance along the axis to the site of the Îł -ray production d (which then can be transformed into the location of Îł -ray-emitting region R Îł ) and the propagation angle with respect to the axis of the accretion disk Φ. To do so, we adopt an identical sample with 809 Fermi-LAT-detected blazars which had been compiled in Pei et al. These four derived parameters stepping onto the stage may shed new light on our knowledge regarding Îł -ray blazars. With regard to the paper of Becker & Kafatos, we obtain several new perspectives, mainly in (1) putting forward an updated demarcation between BL Lacs and FSRQs based on the relation between broad-line region luminosity and disk luminosity both measured in Eddington units, i.e., L disk/ L Edd = 4.68 Ă— 10âˆ'3, indicating that there are some differences between BL Lacs and FSRQs on the accretion power in the disk; (2) proposing that there is a so-called “appareling zone,” a potential transition field between BL Lacs and FSRQs where the changing-look blazars perhaps reside; (3) the location of Îł -ray emission region is principally constrained outside the broad-line region, and for some BL Lacs are also away from the dusty molecular torus, which means the importance of emission components in the jet. [ABSTRACT FROM AUTHOR]

Different kinds of waves and instabilities in the F-region of the ionosphere excited by the relative streaming of the dust beam to the background plasma are studied in the present paper. The dispersion relations of different waves are obtained on different time scales. It is found from our numerical results that there are both a stable upper hybrid wave on the electron vibration time scale and a stable dust ion cyclotron wave on the ion vibration time scale. However, the chaotic behaviour appears on the dust particles vibration time scale due to the relative streaming of the dust particles to the background plasma. Such instabilities may drive plasma irregularities that could affect radar backscatter from the clouds. [ABSTRACT FROM AUTHOR]

Due to the small charge-to-mass ratio of dust particles, it is often necessary to use large magnetic fields of B ≥ 1 T, in order to observe the influence of magnetic forces in laboratory dusty plasmas. However, when experiments are performed at high magnetic fields in capacitively coupled, radio frequency discharges used for these dusty plasma experiments, the plasma is often observed to form filamentary structures between the electrodes that are aligned to the external magnetic field which disrupt the uniformity of the plasma and adversely impact some of our dusty plasma experiments. Recent experiments performed in the Magnetized Dusty Plasma Experiment device seek to identify and characterize these filamentary structures. This paper discusses the morphology of several distinct filamentary modes that are formed in low temperature argon plasmas. Three different spatial modes of filaments that appear to be strongly dependent on the magnetic field and neutral pressure are identified. There is strong evidence that each spatial mode has a threshold condition that is dependent on the ion Hall parameter. The criteria for the formation of the filaments are shown to be consistent with predictions of recent numerical simulations. [ABSTRACT FROM AUTHOR]

Copyright of Iraqi Journal of Science is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central European Agriculture is the property of Journal of Central European Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We investigate the effect of nonthermal electrons modeled by two non-Maxwellian distribution functions, i.e., the (r, q) and Cairn's distributions on the formation of dust acoustic (DA) solitons in an un-magnetized dusty plasma by incorporating the effect of dust streaming. We adopt the pseudopotential technique to obtain solitary wave solutions from fluid equations. It is seen that only rarefactive soliton can be obtained in such plasmas where ions are considered Boltzmannian and electrons non-Maxwellian. We find that soliton characteristics are strongly dependent on the nonthermal spectral indices r, q, and α and dust temperature Td. For (r, q) distribution, it is found that soliton amplitude increases but width decreases when the positive (negative) value of r decreases (increases). For Cairn's distribution, we find that with the increase in α, soliton amplitude decreases. In space environments, such as cometary tails, solar wind, and Earth's magnetosphere, where non-Maxwellian populations of electrons are present, our theoretical results show that the amplitude of soliton remains smaller than the Maxwellian case. Thus, Maxwellian distribution overestimates the soliton amplitude in such space environments. Therefore, we feel that our results will better interpret the results of observations, from cometary tails, and other space plasmas where nonlinear DA structures are likely to be observed. [ABSTRACT FROM AUTHOR]

Solar Orbiter is equipped with electrical antennas performing fast measurements of the surrounding electric field. The antennas register high-velocity dust impacts through the electrical signatures of impact ionization. Although the basic principle of the detection has been known for decades, the understanding of the underlying process is not complete, due to the unique mechanical and electrical design of each spacecraft and the variability of the process. We present a study of electrical signatures of dust impacts on Solar Orbiter's body, as measured with the Radio and Plasma Waves electrical suite. A large proportion of the signatures present double-peak electrical waveforms in addition to the fast pre-spike due to electron motion, which are systematically observed for the first time. We believe this is due to Solar Orbiter's unique antenna design and a high temporal resolution of the measurements. The double peaks are explained as being due to two distinct processes. Qualitative and quantitative features of both peaks are described. The process for producing the primary peak has been studied extensively before, and the process for producing the secondary peak has been proposed before for Solar Terrestrial Relations Observatory (STEREO), although the corresponding delay of 100–300 µ s between the primary and the secondary peak has not been observed until now. Based on this study, we conclude that the primary peak's amplitude is the better measure of the impact-produced charge, for which we find a typical value of around 8 pC. Therefore, the primary peak should be used to derive the impact-generated charge rather than the maximum. The observed asymmetry between the primary peaks measured with individual antennas is quantitatively explained as electrostatic induction. A relationship between the amplitude of the primary and the secondary peak is found to be non-linear, and the relation is partially explained with a model for electrical interaction through the antennas' photoelectron sheath. [ABSTRACT FROM AUTHOR]

The influence of mineral dust deposition on soil formation in the mountain critical zone was evaluated at six sites in southwestern North America. Passive samplers collected dust for 2 years, and representative soil and rock were gathered in the vicinity of each dust sampler. All materials (dust, soil, and rock) were analyzed to determine their mineralogy (with X-ray diffraction), geochemistry (with inductively coupled plasma mass spectrometry (ICP-MS)), and radiogenic isotope fingerprint (87Sr/86Sr and εNd). In addition, the grain size distribution of dust and soil samples was determined with laser scattering, and standard soil fertility analysis was conducted on the soil samples. Results reveal that minerals present in the dust but absent in the local bedrock are detectable in the soil. Similarly, the geochemistry and isotopic fingerprint of soil samples are more similar to dust than to local bedrock. End-member mixing models evaluating soil as a mixture of dust and rock suggest that the fine fractions of the sampled soils are dominated by dust deposition, with dust contents approaching 100 %. Dust content is somewhat higher in soils compared to bedrock types more resistant to weathering. These results emphasize the dominant control that mineral dust deposition can exert on pedogenesis in the mountain critical zone. [ABSTRACT FROM AUTHOR]

Using a uniquely configured glow discharge-based Shivalik Plasma Device-I, we demonstrate a variety of collective phenomena in dusty plasma away from the glow discharge region. The cylindrical glass device produces plasma using parallel disc-shaped electrodes with a smaller anode size than the cathode. The dust microparticles are initially sprinkled over the grounded cathode. These particles acquire a significant negative charge upon plasma formation, resulting in their levitation due to the balance between the Coulomb force and gravity. The new device supports the levitation of a big-sized (10 × 8 × 5 cm3) three-dimensional dust cloud over the glass surface. It contrasts the dusty plasma formations in-between electrodes reported earlier. As the discharge voltage varies from high to low, the dust cloud travels from over the glass surface to between the electrodes. A complex interplay of dust void over the cathode, a sharp density gradient, and gravity lead to self-excitation of collective dust phenomena. It includes dust density waves (phase velocity, vph ∼ 4 cm/s), dust cloud oscillation (frequency, f = 5 Hz), sheared flow (flow velocity, vf ∼ 1 cm/s), and multiple-sized dust vortices. These dust vortices provided an excellent platform for studying turbulent mixing phenomena. The power spectrum analysis agreed with two-dimensional Kolmogorov power-law scaling. This is an ideal dusty plasma apparatus where we can create or move the dust cloud to a location of choice from the glass surface to in-between the electrodes and excite one among many collective dust dynamics. [ABSTRACT FROM AUTHOR]

In this paper, variable coefficients mKdV equation is examined by using Painlevé analysis and auto-Bäcklund transformation method. The proposed equation is an important equation in magnetized dusty plasmas. The Painlevé analysis is used to determine the integrability whereas an auto-Bäcklund transformation technique is being explored to derive unique family of analytical solutions for variable coefficients mKdV equation. New kink–antikink and periodic-kink- type soliton solutions have been determined successfully for the considered equation. This paper shows that auto-Bäcklund transformation method is effective, direct and easy to use, and used to determine the analytic soliton solutions of various nonlinear evolution equations in the field of science and engineering. The results are plotted graphically to signify the potency and applicability of this proposed scheme for solving the above considered equation. The obtained results are in the form of soliton-like solutions, solitary wave solutions, exponential and trigonometric function solutions. Therefore, these solutions help us to understand the potential and physical behaviors of the proposed equation. [ABSTRACT FROM AUTHOR]

Plasmas 28, 053505 (2021).10.1063/5.0045947 12 J. Moreno, A. Khodaee, D. Okerstrom, M. P. Bradley, and L. Couëdel, " Time-resolved evolution of plasma parameters in a plasma immersion ion implantation source", Phys. However, there is still a lack of understanding of the plasma parameters in the complex mixture gas (radical/ion species, electron/ion energy distributions, temperature, etc.) and plasma physics (electron heating dynamics, electron kinetics, wave-particle interaction, dust plasma characteristics, etc.). The "Plasma Physics and Science in Current and Next Generation Semiconductor Process" Special Topic in I Physics of Plasmas i consists of articles on research presented at The 8th International Conference on Microelectronics and Plasma Technology (ICMAP), which was held in Hwaseong, South Korea, January 17-20, 2021.[1] The "Plasma Physics and Science in Current and Next Generation Semiconductor Process" Special Topic is devoted to understanding such plasma source, plasma parameters, plasma-surface interaction, and processing results in semiconductor process and its related fields, and to bring new insight from theory and experiment for the next generation of plasma process techniques. [Extracted from the article]

In this paper, a (2+1)-dimensional Kadomtsev–Petviashvili (KP) equation is studied from the governing equations of dusty plasma by means of multiscale analysis and reduced perturbation method. We utilize the generalized exponential rational function method to give various forms of analytical solutions with free parameters of the corresponding equation by using Mathematica software calculation. Then, appropriate parameter values are selected to draw the three-dimensional (3D) diagram and contour diagram of the analytic solutions. We also give the influence of these physical parameters on wave amplitude, waves profile, and stability of waves. The results show the generalized method is a reliable mathematical method to solve similar nonlinear equations in mathematical physics and these solutions can enrich the physical behavior of the equation in dusty plasma. [ABSTRACT FROM AUTHOR]

In this paper, the cylindrical shock wave propagation in a perfectly conducting rotating mixture of micro size dust particles and van der Waal gas with magnetic field either axial or azimuthal and monochromatic radiation is investigated. The effect of thermal radiation is included in the energy equation of the governing system. In our study, it is assumed that the flux of radiation moves in the mixture of particles and real gas with invariable intensity and the shock wave is moving appositive to the direction of radiation heat flux and the energy is engrossed behind the cylindrical shock only. In the present model, dusty gas is assumed to be a mixture of micro size dust particles and van der Waal gas in which solid particles are continuously distributed and the equilibrium flow conditions are assumed to hold in the entire flow-field region. The effects of the particles' density to the initial gas density ratio, the real gas effect, rotational parameter, the concentration of mass of the micro size dust particles in the conducting mixture, Alfven-Mach number and the adiabatic exponent on shock and on the physical variables such as velocity, density etc. are discussed. It is found that due to the rotating medium consideration or by an increase in small particles density to the initial gas density ratio, the shock wave strength increases. Also, it is significant to memorize that the strength of the shock wave decreases by an increase in the strength of initial magnetic field or gas non-ideal parameter or the adiabatic index. [ABSTRACT FROM AUTHOR]