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The structure and phase transition of a two‐dimensional (2D)$$ \left(2\mathrm{D}\right) $$ dusty plasma, confined by an anisotropic power‐law potential and interacting via a screened Coulomb potential, were investigated using Monte Carlo simulations. The study varied the number of particles (N$$ N $$), screening strength (k$$ k $$), eccentricity parameter (α$$ \alpha $$), and confinement power parameter (n$$ n $$) to characterize the system's structural properties. [ABSTRACT FROM AUTHOR]

A kettle reboiler uses the latent heat from the condensation of high-temperature and high-pressure steam in the tube to produce low-pressure saturated steam in the outer shell. The deposition of particles on the tube may change the boiling heat transfer mode from nucleate boiling to natural convection, thereby deteriorating the heat transfer performance of the kettle reboiler. Therefore, it is very important to explore the deposition characteristics of particles in the kettle reboiler. In this study, the RPI boiling model based on the Euler–Euler method is used to analyze the water boiling process on the surface of the tube bundle. The DRW model and critical adhesion velocity model based on the Euler–Lagrangian method are used to calculate the motion of particles during the boiling process and the deposition (rebound) behavior. The results show that the boiling of liquid water enhances the local flow velocity of the fluid, so that the maximum flow velocity appears around the near-wall region. The local high-speed flow disperses the particles in the wake flow of the tube bundle, which inhibits the impact of particles on the wall. As the particle size increases, the wall adhesion and fluid drag on the particles are weakened, and the gravity effect gradually becomes dominant, increasing the residence time of the particles in the tube bundle and the frequency of particle impact on the wall. The particle deposition ratio first decreases and then increases. Ultimately, most particles will be deposited in the low-speed area at the end of the tube bundle. [ABSTRACT FROM AUTHOR]

The driven-dissipative Langevin dynamics simulation is used to produce a two-dimensional (2D) dense cloud, which is composed of charged dust particles trapped in a quadratic potential. A 2D mesh grid is built to analyze the center-to-wall dust density. It is found that the local dust density in the outer region relative to that of the inner region is more nonuniform, being consistent with the feature of quadratic potential. The dependences of the global dust density on equilibrium temperature, particle size, confinement strength, and confinement shape are investigated. It is found that the particle size, the confinement strength, and the confinement shape strongly affect the global dust density, while the equilibrium temperature plays a minor effect on it. In the direction where there is a stronger confinement, the dust density gradient is bigger. [ABSTRACT FROM AUTHOR]

A theoretical model is presented that describes the settling regime of plasma-dust clouds in the mesosphere of Mars. The values of the characteristic sizes of cloud dust particles predicted by the model are calculated. It is shown that an important factor influencing the formation of plasma-dust structures in the Martian atmosphere is the Rayleigh–Taylor instability, which limits (from above) the permissible sizes of dust particles in the cloud. [ABSTRACT FROM AUTHOR]

AbstractIn this instigation, the heat and mass transfer pattern on Eyring-Powell nanofluid with suspension of dust particles is focused. For heat transfer phenomenon, the Eyring-Powell nanofluid capturing the variable thermal conductivity. Furthermore, the variable and mass diffusivity assumptions are entertained for summarizing the observations chemical reaction phenomenon. The flow is endorsed to magnetic force impact. The additional impact of Brownian motion and thermophoresis consequences have been adopted. The numerical computations with shooting technique are performed. The physical aspects of parameters have been observed graphically. Based on depicted observations, it is examined that the fluid velocity reduces due to interaction velocity parameter which reverse trend is noted for dust particles velocity. The temperature profile for dusty fluid particles enhanced due to interaction parameter for temperature. Furthermore, the concentration profile reduces due to concentration interaction parameter. Current results present applications in solar energy, thermal processes, heat transform devices cooling systems, plasma, manufacturing processes, energy systems, etc. [ABSTRACT FROM AUTHOR]

Falkner's‐Skan flows are one‐dimensional flows widely used in fluid dynamics and boundary layer theory. They optimize heat exchangers and cooling systems, enhance turbine and compressor blades in turbomachinery, and provide consistency and quality in semiconductor fabrication. Additionally, they assist in pollution management and environmental impact assessments. The variety of Falkner's‐Skan flows clarifies fluid flow phenomena and their practical applications. This article aims to explore the impact of surface temperature on the flow behavior of dusty fluid in Falkner's‐Skan flow. The study focuses on the flow of dust particles in a channel formed by two infinite parallel plates. The study assumes that the particles are round and uniformly dispersed in the fluid. Furthermore, the article takes into account the effect of radiation on the energy equation. With the findings of this study, we hope to gain a better understanding of the dynamics of Falkner's‐Skan flow and contribute to the development of effective strategies for managing the flow of dusty fluids. The right plate's movement at free stream velocity Ue=axn ${U}_{e}=a{x}^{n}$ causes the fluid to flow. Partial differential equations are used to represent the behavior of the flow. The Poincare‐Light Hill Technique yields exact answers. Visual representations of the temperature and velocity curves show the effects of different factors. It is possible to create graphic pictures of the fluid and dust particles using Mathcad‐15. Furthermore, critical fluid characteristics for engineers, such as skin friction and heat transfer rate, are analyzed and tabulated. These evaluations include the heat transfer rate at the wedge surface and the influence of this enhancement on surface viscous drag forces. [ABSTRACT FROM AUTHOR]

This study looks at the Darcy–Brinkman flow across a stretched sheet of porous dissipation and frictional heating. The geometry of a steady flow of dust particles fluid through a porous material in the existence of slip effect and porous dissipation is the subject of this study. The equations that govern the system are shown and summarized as boundary layer assumptions, and then modified into framework of first-order DEs using the similarity approach. By using similarity transformation, a two-dimensional nonlinear partial differential equation is decreased to a sequence of nonlinear ordinary differential equations (ODEs). Then, by employing numerical techniques such as Maple packages, the solution of system of nonlinear equations is represented using the RK4 method. The numerical findings are derived under specific unique situations. The Nusselt number and coefficient of skin-friction are also given numerically. The increase in Brinkman number γ raises the temperature profile for both the dusty and the fluid phases. The results also demonstrate that rise in the suction number S falls the temperature distribution within the boundary layer for the dusty phase and fluid phase. For a variety of flow quantities of attention, the variation of parameters is studied, and the outcomes are reported in the shape of graphs and tables. Several industrial processes make advantage of boundary layer flow and heat transfer over such a stretched surface in porous materials. [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]

Background and Aim: The recent review of research conducted in the field of air pollution and sports shows that there is a serious impact of air pollutants as well as the new pollutant of dust particles, and it is imperative to pay attention to this issue. This research aims to investigate the effect of regular exercise on lung function and amino acid arginine-alanine in traffic police of the provinces affected by dust particles in Iran. Methods: Forty traffic police officers (age: 23.62 ± 6.4 years; body mass index: 27.44 ± 4.7 kg/m2) were voluntarily selected from the centers of Khuzestan, Ilam, and Kermanshah provinces and randomly assigned to two control and regular physical activity groups. Regular physical activity included: 30 sessions, circuit training three times a week including hanging from the chin up (20 seconds), jumping over obstacles (knee height) at a distance of one meter for a total of 540 cm, Sit-ups (30 seconds), chest press (70% 1RM-8 repetitions), leg press (70% 1RM -8 repetitions), back extension (15 repetitions), calf raise (70% 1RM -8 repetitions), zigzag jump (20 repetitions), six to ten reputation Illinois Agility Test with a 30-second rest interval. Before the study, 48 hours before the occurrence of dust particles, and after the study fat percentage, amino acids, WBC, and FEV1/FVC were measured. To examine the research data, we used the mean and standard deviation as well as repeated analysis of variance (P ≥0.05). Results: It was found that time (pre-test-May 12, 2023) had a significant effect on amino acids argininealanine, maximum oxygen consumption, body fat percentage, and FEV1/FVC in the training group (P <0.05). In the control group, there was no significant difference in the amino acid arginine-alanine, maximum oxygen consumption, body fat percentage, or FEV1/FVC (P >0.05). However, the effect of time was present in the control group only for white blood cells (P <0.001). In terms of body fat percentage, there was a significant difference between the control and exercise groups (P = 0.01), as well as maximum oxygen consumption (P = 0.01). Conclusion: This study has demonstrated that regular exercise training can improve lung function, aerobic fitness, body fat percentage, and levels of amino acids involved in the immune system, as well as increase muscle mass and anti-inflammatory effects that reduce dust particle damage in those exposed to dust particles. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of steady two-dimensional magnetohydrodynamics (MHD) migration of dusty fluid across a stretching sheet with the inclusion of Darcy–Forchheimer porosity and Brownian dispersion. The most significant aspect of the ongoing problem is elaborating the entire context with dusty and fluid phases. The governing partial differential equations (PDEs) are transmuted into non-dimensional ordinary differential equations (ODEs) by implementing similarity transformations. The MATLAB script has used the bvp4c strategy to accumulate a visualization of the computational observations. Also, this study illustrates an assessment of the effects of significant parameters on non-Newtonian fluids and fluids with a dusty phase. It is observed that the thermal boundary layer is enhanced with the increasing strength of the mass concentration of dusty granules ( Γ ν ) and Eckert number (Ec) for both scenarios, while in the case of fluid interaction temperature parameter ( β t ) the scenario is opposite for dusty and fluid phases. Moreover, the heat transfer rate intensifies with the increasing effect of thermal radiation, and magnetic field. The significant variations in the various physical quantities are represented through tabular and graphs. [ABSTRACT FROM AUTHOR]

This paper analyzes the stabilizing effect of stone dust, granite dust, marble dust, and calcium lignosulphonate on construction materials and natural soils during road construction. The ultimate aim was to enhance the soil's engineering properties such that the pavement constructed could correctly withstand the load applied. To achieve this, every stabilizer was amalgamated with the soil at various percentages between 5 and 50%. Measurements were made of Atterberg limit tests, moisture content, and specific gravity. The research demonstrated that a diminution in optimal moisture content was seen, with an elevation in maximum dry density and California bearing ratio (CBR). Enhancements in the unconfined compressive strength were also identified. The outcomes determined that the untreated soil's CBR was 2.27% and in the case of soil with 45% additives, the CBR attained was 5.05%. When the soil was mixed with 50% additives, performance of 30.21%, 17.42%, and 12.82% was exhibited for (a) liquid limit, (b) plastic limit, and (c) plasticity index. Moreover, via the addition of presented stabilizers, the soil's mechanical properties were elevated appreciably. [ABSTRACT FROM AUTHOR]

A kettle reboiler uses the latent heat from the condensation of high-temperature and high-pressure steam in the tube to produce low-pressure saturated steam in the outer shell. The deposition of particles on the tube may change the boiling heat transfer mode from nucleate boiling to natural convection, thereby deteriorating the heat transfer performance of the kettle reboiler. Therefore, it is very important to explore the deposition characteristics of particles in the kettle reboiler. In this study, the RPI boiling model based on the Euler–Euler method is used to analyze the water boiling process on the surface of the tube bundle. The DRW model and critical adhesion velocity model based on the Euler–Lagrangian method are used to calculate the motion of particles during the boiling process and the deposition (rebound) behavior. The results show that the boiling of liquid water enhances the local flow velocity of the fluid, so that the maximum flow velocity appears around the near-wall region. The local high-speed flow disperses the particles in the wake flow of the tube bundle, which inhibits the impact of particles on the wall. As the particle size increases, the wall adhesion and fluid drag on the particles are weakened, and the gravity effect gradually becomes dominant, increasing the residence time of the particles in the tube bundle and the frequency of particle impact on the wall. The particle deposition ratio first decreases and then increases. Ultimately, most particles will be deposited in the low-speed area at the end of the tube bundle.

Landfill biogas contains large amounts of toxic and harmful impurities and may be a source of microbiological contamination of both the complex municipal waste landfill itself and adjacent territories. This paper uses modern biotechnologies designed to protect the environment to study the quantitative and qualitative composition of biogas for harmful factors, as well as for harmful substance removal from biogas. An assessment was made of air purification in the premises near landfills and adjacent territories using green plantations and a biological system based on an apparatus–biological complex for purification from microbiological contamination. The data obtained in our laboratory studies show that such apparatus–biological complexes can reduce the negative influence on the personnel and workers at operative points and on the inhabitants of adjacent territories by air purification. [ABSTRACT FROM AUTHOR]

An attempt has been made to analyze the effect of second order resistance for a steady, dusty fluid considering magnetohydrodynamic (MHD) and also the characteristics of fluid like permeability, porosity, solutal diffusivity and thermal conductivity being varied. Here the basic equations are coupled, non-linear Partial Differential Equations (PDEs), which are changed by similarity transformations to higher order Ordinary Differential Equations (ODE). After being transformed the higher order ODE that where obtained are resolved numerically. Shooting technique is employed here and the values are tabulated for various pertinent parameter variations. The effects of the inertia, concentration and interaction, mixed convection, magnetic and many other parameters are discussed and plotted graphs for velocity, concentration and temperature. The magnetic force enhances velocity. It was found that the present study correlates with the existence results. [ABSTRACT FROM AUTHOR]

The effects of slips and porosity on the channel walls in the flow of a heatabsorbing/ generating dusty ferrofluid streaming through a porous medium are investigated in this article. The channel is upright and subjected to a transverse magnetic flux along with thermal radiation. Kerosene with magnetite is used as the base fluid. The basic equations of the channel flow, which seem dimensional, are redesigned in a dimensionless manner utilizing non-dimensional variables. The variable separable method approach is used to solve the obtained equations analytically. The graphs demonstrate the behavior of these parameters on the flow fields, skin friction, and heat transmission rate, and are explained briefly. Results reveal that the flow velocity for heat-generating fluids is greater than the heat-absorbing liquids. The fluid velocity upsurges with the improved values of the velocity slip parameter. The heat-generating dusty liquid has a higher heat transmission rate as compared to heatabsorbing dusty liquid. [ABSTRACT FROM AUTHOR]

Due to its significant applications in magnetic devices for cell separation, magnetic drugs for cancer tumor treatment, blood flow adjustment during surgery, magnetic endoscopy, and fluid pumping in industrial and engineering processes, magnetohydrodynamics (MHD) has a wide range of applications. Therefore, the aim of this study to investigate the Relative Magnetic Field and slipping effect on Casson dusty fluid of two-phase fluctuating flow over inclined parallel plate. More exactly, the relative magnetic phenomena are fixed relatively to the plate (MFFRP) or fixed relatively to the fluid (MFFRF). The mathematical modeling was established as the set of partial differential equations for dusty Casson fluid. Buckingham's pi theorem is used to find out the dimensionless variables, to make our system dimensionless. The solution in perturb form is to find out by incorporating Poincare–Lighthill perturbation technique (PLPT). To know in-depth different parameters the graphical results for both velocities are plotted with the help of software Mathcad- 15. It is clearly detected that the relative magnetic field performs a vital part in the fluid as well as particle motion. Moreover, the relative magnetic field play a vital role in the decreasing of skin friction of both plates.

Nanoparticles are used in many industrial processes due to their wider applications. The current inspection deals the utilization of nanoparticles to boost thermal efficiency. This research reports the inclusion of nanoparticles and dust particles for the flow of tri-hybridized nanofluid with thermal transport in a stretchable porous sheet with Hall and Ion slip contribution. The mechanism of thermal transport is carried out by engaging the radiation and Joule heating effects and the flow-presenting equations are derived from the principle of boundary layer theory in Cartesian coordinates. The principle of boundary layer theory was engaged to derive momentum transport for tri-hybridized nanoparticles, dust particles and thermal transport in the presence of Joule heating and external heat sources. The derived equations are in the form of coupled PDEs (partial differential equations) for three-dimensional model which are converted into coupled ODEs (ordinary differential equations) and the simplified expressions are handled numerically via finite element procedure. The results are prepared for the solution in the form of tables and graphs against different involved parameters. The results reveal that thermal enhancement and motion of the particles for the case of the fluid phase are higher than the thermal enhancement and motion for the case of the dusty phase and additionally, thermal performance for the case of tri-hybrid nano-structures (SiO2-TiO2-Al2O3/engine oil) is higher than thermal performance for the cases of hybrid nano-fluid.

Cement manufacturing industries are among the most common sources of air, water (surface and ground) and noise pollution, indirectly affecting those residing near cement plants. The present study was conducted to quantify the effect of cement dust emission from Cement Corporation of India's Bokajan factory in Assam, North East India, on the residences nearby, some selected household activities and the general well-being of people in its vicinity. An experiment was carried out to estimate the accumulated cement dust in households. The findings showed that household activities performed by the residents were dependent upon dust exposure, thus affecting the degree of cleaning and maintenance of their dwellings. Further, the adverse effect of cement dust was found to be more pronounced for people residing in the southern direction and lowest for those in the eastern direction. [ABSTRACT FROM AUTHOR]

The E×B plasma systems play an important role in the technologies like electric space propulsion and magnetized plasma sources used in plasma material interaction/surface processing. However, due to the gradient in plasma density, collisions and external fields such systems become prone to the instabilities and also dust particles are generated during the plasma processing. Hence, this article discusses the growth of gradient driven instability in a cross-field plasma, where both the ions and the electrons are magnetized and dust particles also exist. Using the fluid approach, we write basic equations and then derive an equation in terms of perturbed potential. The unperturbed part of this equation leads to the dispersion equation which is solved numerically for obtaining the growth rate of the instability. The normalized form of the growth rate is investigated in greater detail under the effect of dust density, dust mass, dust temperature, external magnetic field, ion temperature and ion temperature gradient. [ABSTRACT FROM AUTHOR]

Excessive lead (Pb) in industrial dust increases serious concerns about its potential impact on human health and environment. Urban trees, as a green and cost-effective alternative, are now considered an eco-sustainable tool used to monitor and mitigate this environmental pollution. The present study investigated the effect of dust particles and lead deposition on plant functioning and micromorphology of two common roadside plants, Eucalyptus camaldulensis and Conocarpus lancifolius, in an industrial city, Faisalabad, Pakistan. Tree leaf samples were collected from 20 sites varying in dust exposure intensity. These samples were analyzed for antioxidant enzymes such as superoxidase dismutase (SOD), peroxidases (POD), and catalases (CAT), as well as for proline and protein contents. An increased leave of reactive oxygen species and proline contents in response to increasing dust load and lead tissue lead concentrations across the tested locations suggested the sensitivity of plants to urban dust. This study suggested that C. lancifolius leaves accumulated relatively higher dust particles and lead contents than E. camaldulensis. However, this excessive dust deposition and lead uptake inhibited carbon and protein synthesis in E. camaldulensis and C. lancifolius, as evidenced by relatively lower leaf photosynthesis and protein contents. We also found that the concentration of CAT (4.90 nmol min–1 g–1 protein), SOD (38.42 U mg–1 protein), and POD (2.64 µmol min–1 g–1 protein) were higher in E. camaldulensis. The results provide experimental support for the hypothesis that genetically rich populations are better adapted to changing conditions and suggest that C. lancifolius is less sensitive to dust load and lead uptake in terms of growth reduction. Regarding lead uptake and dust removal, C. lancifolius performed better as compared to E. camaldulensis. The above findings are helpful in the quantification of services, assessing the diversity, and identification of eco-friendly trees in urban areas. Furthermore, this study will be helpful for the formulation of future tree-planting policies in urban areas. [ABSTRACT FROM AUTHOR]

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The mode of subsidence of layered structures in the ionosphere of Mars has been studied taking into account the compositional features of the Martian atmosphere. The characteristic sedimentation rates of dust particles, their sizes and charges, as well as the sedimentation time of layered structures are calculated. The results obtained can be used in the study of atmospheric phenomena on Mars in the course of upcoming space missions. [ABSTRACT FROM AUTHOR]

The process of gas ionization-recombination and dust particle charging under the effect of X-ray radiation in the conditions of space plasma has been investigated. Conditions have been found under which, as a result of radiation exposure, dust particles in a protoplanetary disk can acquire a positive charge even under low gas ionization. [ABSTRACT FROM AUTHOR]

Due to the important application of magnetohydrodynamic in cancer tumor treatment, magnetic drug targeting, magnetic endoscopy, magnetic devices for cell separation, fluid pumping in industrial and engineering developments, and adjusting blood flow during surgery. Therefore, we investigate the relative magnetic field analysis of the two-phase fluctuating flow of Casson dusty fluid over a parallel plate. More exactly, the relative magnetic phenomena are fixed relative to the fluid (MFFRF) or fixed relative to the plate (MFFRP). Moreover, the entropy generation and Bejan numbers analysis are also considered for both MFFRF and MFFRP. The mathematical modeling was established as the set of partial differential equations for dusty Casson fluid. Buckingham's pi theorem is used to find out the dimensionless variables, to make our system dimensionless. The perturb solution is to find out by incorporating Poincare–Lighthill perturbation technique. To know in-depth different parameters, the graphical results for both velocities are plotted with the help of Mathcad-15 software. It is observed that the relative magnetic field plays an important role in the fluid as well as particle motion. The relative magnetic field is affecting the entropy generation as well as the Bejan number. This study will help out in the adjusting of blood flow during surgery and fluid pumping in industrial and engineering process. [ABSTRACT FROM AUTHOR]

In order to reduce the harm of dust dispersion in open-pit coal mine to the mining environment and the damage of personnel and equipment, this paper carried out the research on dust migration, distribution and treatment in open-pit coal mine by taking Hequ open-pit coal mine as the engineering background.The results show that: ①by means of on-site monitoring, this study analyzes the changes of dust concentration in different areas, and further determines the main dust producing areas of open-pit coal mine; ②The fractal dimension is introduced into the migration and distribution of dust, and the relationship between dust particle size, wind speed and fractal dimension is studied; ③A clean, efficient and low-cost chemical dust inhibitor was developed by studying the ratio of chemical dust inhibitor based on polymer materials.The chemical dust inhibitor has a good capture effect on dust particles and can form a film after spraying to prevent secondary dust.

Iran's location in the drylands belt has increased the frequency of dust storms in western parts of Iran, particularly the city of Kermanshah and negative environmental impacts. Arid lands, as one of the main sources of suspended dust in the atmosphere, face problems such as sandstorms, high levels of dust particles and reduced visibility, which are major climate problems in the country, especially in the border provinces. The purpose of the present study is to investigate the performance of a numerical model between the meteorological-chemical atmosphere scale called WRF-Chem model in the simulation of the concentration of suspended particles in Kermanshah region. By comparing the spatial distribution and concentration of suspended particles, meteorological parameters simulated by the model, and the available observational values for PM10 particles in Kermanshah, the efficiency of the WRF-Chem model was evaluated. The results of the simulation of PM10 particles for the studied days showed that the central and western deserts of Iraq, Syrian desert, Kuwait and northern Saudi Arabia are the main source of dust storm. Due to the logical correlation between dust particle emissions and temperature and relative humidity parameters, accurate estimation of these parameters is very effective in PM10 particle simulation accuracy. Based on the analysis of the PM10 variables, temperature and relative humidity and the plotted graphs and their comparisons, a favorable agreement was achieved between the simulated and measured values for PM10, temperature and relative humidity.

The intensive of this study is to examine the melting heat and second-order slip (SoS) effect at the boundary in nanofluid and hybrid nanofluid (HN) ethylene–glycol (EG) based fluid through a curved surface using the Modified Fourier Law (MFL) and dust particles. Considering similarity transformation, the PDEs are converted to ODEs and then solved numerically by using the finite element method (FEM). The effects of solid volume fraction (SVF), melting heat factor, curvature factor, first and second-order slip factor, fluid particle concentration factor, and mass concentration factor on the velocity field, dust phase velocity (DPV), temperature field, dust phase temperature (DPT), and the Ski Friction (SF) are investigated through graphs and tables. The thermophysical properties of nanofluid and HN are depicted in tables. The novelty of the present work is to investigate the dusty- and dusty-hybrid nanoliquids over the curved surface with a melting heat effect and MFL which has not yet been studied. In the limiting case, the present work is compared with the published work and a good correlation is found. The confirmation of the mathematical model error estimations has been computed. [ABSTRACT FROM AUTHOR]

Space dust and dusty (complex) plasma are one of the most common manifestations of matter in space. Non-atmospheric bodies of the Solar System, such as the Moon, asteroids, comets, some satellites of the planets, are directly affected by external factors of outer space—solar electromagnetic radiation, interplanetary plasma flows, cosmic rays, micrometeors. Under the influence of these factors, regolith is formed on the surface of bodies during geological epochs. Under the influence of impacts of high-speed micrometeors, dust particles of regolith scatter at different speeds. Most of them return to the surface, but some form dust clouds or lose their gravitational connection with the parent body. Under the action of solar radiation, the surface acquires an electric charge, and dust particles under certain conditions can break away from the regolith surface and levitate. Observational evidence of such dynamic phenomena has been recorded on the Moon and on some asteroids. The study of the physical processes responsible for the activation of dust particles and their dynamics is of great interest for fundamental science and practical purposes. The article discusses the main processes occurring under the influence of outer space factors on regolith, as a result of which dust particles move and a near-surface plasma-dust exosphere is formed. Unresolved issues are discussed. Methods and means of laboratory modeling in studying the activation and dynamics of dust particles are considered. [ABSTRACT FROM AUTHOR]

Dusty fluids are utilized to minimize heat in systems like gas-freezing systems and nuclear-powered reactors, among other places. The present study aims to investigate the effect of Newtonian heating on dusty fluid flow. Between two parallel plates, the two-phase MHD fluctuating flow of the dusty fluid is considered. The dust particles inside the fluid are thought to be spherical and uniformly distributed. The generation and absorption of heat were also taken into consideration. The motion of the fluid is due to the motion of the right plate with free stream velocity Ut. Partial differential equations are utilized to represent the flow regime. The Poincare-Light Hill Technique is used to find exact solutions. The impact of parameters on the temperature and velocity profiles are shown graphically. Skin friction and rate of heat transfer, two essential fluid parameters for engineers, are also evaluated in tabular form. The velocity of the fluid is shown to decrease with increasing magnetic field. The Newtonian heating phenomena has an effect on the plate’s heating.

Tiny particles in the Earth's atmosphere create dust that originates from various sources, including air pollution. The resulting dust contains numerous dust particles, and the size of these dust particles is sometimes homogeneous or irregular. The presence of dust in any kind of fluid in nature is a normal thing and this matter can no longer be ignored. Considering this fact, heat and mass transfer of the dusty Casson fluid flow over a permeable stretching sheet is investigated incorporating heat dissipation, magnetic and radiative fields, heat source or sink, and the effect of temperature gradient referred to as Dufour effect and thermophoresis stated as Soret effect. In this research, similarity analysis is used to transform the nonlinear governing partial differential equations into a set of nonlinear ordinary differential equations (ODE). Then the nonlinear ODE systems have been formulated using the finite difference method with the central difference technique and then solved. In addition, a comparison with other research findings is presented, which yields a quantitatively good agreement. Results revealed that the Eckert number, surface temperature parameter, conduction-radiation parameter, and Dufour effect lead to a substantial increase in the fluid flow rate and fluid temperature, the temperature of the dust particles, and momentum and thermal boundary layers. The magnitude of the drag coefficient becomes stronger with the augmentation of the Hartmann number, the mass concentration of dust particles, and the suction parameter. Moreover, an increase in the surface temperature parameter, conduction-radiation parameter, mass concentration of dust particles, and non-Newtonian Casson fluid parameter enhances the local Nusselt number. [ABSTRACT FROM AUTHOR]

Exploring life conditions on the near-Earth planets and satellites before carrying out human missions is an important task for space agencies. For that purpose, scientific space missions usually include instruments to measure climatological variables. Within this space instrumentation and measurement context, dust sensors (DSs) aim to measure dust particles in suspension and provide valuable information for persons and equipment life conditions, while they must deal with low signal-to-noise ratios (SNRs). For example, the Exomars mission is focused to characterize the weather on Mars surface and include up to four DSs based on different technologies: infrared (IR), laser, interferometry, impact sensors, and electric field activity sensors. Due to the tight budget in terms of area, weight, power consumption, and data budget in aerospace instruments, as well as ionizing radiation and extreme temperatures, current solutions present low scalability and configurability. In this article, a novel system proposal that extracts valuable information from noisy signals obtained from IR sensors aimed to measure airborne dust is presented. The solution provides competitive capabilities in terms of power consumption, data budget, SNR, and reconfigurability. It has been implemented in a rad-hard Microsemi field programmable gate array (FPGA) (RT54SX32S). Therefore, robustness and scalability are guaranteed. The results reported a maximum power consumption of up to 141 mA (@12 Vdc), a sensitivity of 19.5 mV (input signal), and a data budget of 32 B/s. This research possesses great potential to further instruments not only in planetary exploration but also at Earth applications. [ABSTRACT FROM AUTHOR]

Naturally occurring radionuclides have been reported to occur in high concentrations in gold deposits and with other metal ores in Africa. These radionuclides can be released during mining operations and ore processing, causing harmful radiation exposure of mine workers and nearby populations, and may render the mining waste rocks unusable. One large gold mine site in Burkina Faso, near Mana Village, was assessed for naturally occurring radionuclide levels. The area was surveyed for ambient radiation dose rate. Samples from waste rock and sludge from ore milling were analysed by alpha spectrometry, confirming the presence of naturally occurring radionuclides but in relatively low concentrations. It was concluded that mine workers are not exposed to radiation doses significantly above the unmodified natural radiation background. Furthermore, waste rock piles from mining operations can be recycled and used in road construction. [ABSTRACT FROM AUTHOR]

Dust pollution has long been a challenge in the blasting excavation of underground metal mines, and uncontrolled diffusion of dust particles seriously endangers the health and safety of workers as well as the environment in underground space. Most existing research on dust diffusion focuses on fully mechanized coal mining face or borehole drilling, where the dust source emission characteristics differ significantly from metal mine blasting excavation. Furthermore, it is still unclear how the ventilation modes of Far-Pressing-Far-Absorption (FPFA), Near-Pressing-Far-Absorption (NPFA), and Far-Pressing-Near-Absorption (FPNA) affect the mechanism of dust diffusion in the breathing zone. In this work, gas-solid flow characteristics in a typical metal mine blasting tunnel are numerically studied based on Euler-Lagrange method. The interphase forces between airflow and dust particles are comprehensively modeled, and the particle diffusion effect caused by fluid turbulence is described by the discrete random walk model. Five typical regions for airflow disorder phenomena in the working tunnel are predicted, including the jet development region, the return airflow core region, the airflow reversal region, the airflow recirculation region, and the secondary flow region. The spatial distribution of dust exhibits nonuniform characteristics under turbulent airflow transport. The time results of the monitored dust concentration reveal that the junction of the working tunnel and the return airway is a key area of focus for the prevention and control of dust pollution. Among the three ventilation modes, the Far-Pressing-Near-Absorption (FPNA) ventilation mode has the best dust removal efficiency. The supply vent further from the blasting face allows the jet to fully develop, while the exhaust vent closer to the blasting face allows dust particles to be drawn in and discharged earlier. Under the condition of fixed total power consumption for the supply and exhaust fans, a larger exhaust airflow velocity helps remove dust from the breathing zone. [Display omitted] • Two phase flow of air and dusts in underground metal mine tunnels are simulated. • Effects of three hybrid ventilation modes, FPFA, NPFA, and FPNA, have been revealed. • Far-Pressing-Near-Absorption ventilation mode has the best dust removal efficiency. • Effects of supply and exhaust air flow rates on dust diffusion are revealed. • Five typical regions for airflow disorder in the working tunnel are predicted. [ABSTRACT FROM AUTHOR]

This paper presents the results of studying the impact of a plasma beam during the interaction of divertor candidate materials in a coaxial plasma accelerator, where graphite and tungsten plates were used as candidate materials. The authors consider the contribution of surface defects (cracks, craters, bubbles) and structural changes (recrystallization) in candidate materials to dust formation under the action of a plasma beam. The other aspect studied in the paper is the erosion of copper substrates (nearby components) under the action of a hot target dust cloud with account for the kinetic influence of hot dust particles on nearby components. It should be noted that these particles are formed by the erosion of the material by the plasma beam. Scanning electron microscopy (SEM), elemental and X-ray diffraction analysis (XRD) were used to study the material surface morphology, chemical composition, and crystal structure. The authors also consider some undesirable effects revealed after irradiation of divertor candidate materials. The obtained experimental results will be useful for evaluating the prospects for further application of these materials in existing and future fusion reactors (e.g., in the international fusion reactor ITER).

The purpose of this study was to examine the vegetation dynamics of various lawn grass species in the city of Apatity, Murmansk region, when exposed to anthropogenic and atmospheric pollution impacts. The dust concentration in the atmospheric air was recorded, its mineralogical analysis was carried out, and the dynamics of the development of various lawn types under the anthropogenic load was studied. Cases of exceeding the MPC of dust particles in the atmospheric air were recorded. Nepheline grains were found in the dust samples, which is indicative of pollution migration from the nearby tailings storage facility. It was shown that lawns are able to grow intensively in severe climatic conditions and under the influence of mining and processing enterprises. [ABSTRACT FROM AUTHOR]

Soiling consists of the accumulation of dust on the solar panel's surface and has a deleterious effect on solar photovoltaic devices' performance, which varies with location. However, soiling losses and rates are significantly under-reported or underestimated since regional differences and seasonal variations are overlooked. Accurate prediction of PV soiling losses for a particular location can save revenue losses associated with a solar PV system. This research investigated the effect of soiling on PV performance through optical losses by employing a low-cost soiling station. Low iron glass coupons (5 mm × 5 mm) were exposed on three angles (vertical, tilt-45°, and horizontal) in seven sites across Nigeria to collect annual, seasonal and monthly soiling data. Each coupon was then subjected to optical characterisation using a spectrometer and imaging analysis using the SEM/EDX. The finding shows significant optical losses across the country, with all the highest rates recorded on coupons exposed on the horizontal plane, where the maximum loss of 88% was recorded on the Abuja, North Central (ABV) coupon. SEM/EDX finding illustrated minerals with the potential to affect light transmittance, and the pollutant data confirmed the particles. The optical results were further employed to map the soiling distribution across the country. A wide deviation was observed from the data on the Global Solar Atlas, as it disproportionately underestimated the soiling losses across the world. [ABSTRACT FROM AUTHOR]

This work aims to offer a mathematical model for two-phase flow that investigates the interaction of Casson nanofluid and dust particles across a stretching surface. MHD Darcy–Forchheimer porous medium and Fourier's law through Cattaneo–Christove thermal flux are also considered. The governing equations for the two phases model are partial differential equations later transmuted into ordinary ones via similarity transforms. The Runge–Kutta method with the shooting tool is utilized numerically to solve the boundary layer equations computed in MATLAB to obtain numerical results for various pertinent parameters. The numerical outcomes of momentum, temperature, and concentration distribution are visible for both phases. The results of the skin friction, heat transfer coefficients, and the Sherwood number are also visible in the graphs. Furthermore, by comparing the current findings to the existing literature, the validity of the results is confirmed and found to be in good agreement. The fluid velocity is reduced against increasing strength of Casson fluid parameter, enhanced the fluid phase and dust phase fluid temperature. The temperature declines against the growing values of the relaxation time parameter in both phases. Dusty fluids are used in various engineering and manufacturing sectors, including petroleum transportation, car smoke emissions, power plant pipes, and caustic granules in mining. [ABSTRACT FROM AUTHOR]

The agricultural landscape constitutes a mosaic of various crop plots intertwined with non-disturbed natural areas. Extensive use of pesticide spraying can pollute the natural areas, causing damage to the natural food webs. The damages to the natural systems can be temporary and cumulative. Although many studies have dealt with the results of pesticide spraying drift to the natural environment, we lack knowledge on the role of dust particle transfer of pesticides. The study aims to investigate the dust particles as pesticide carriers. It examines the presence and accumulation of pesticides in vegetation and soils of the farmlands and natural areas nearby in two different climatic zones, Mediterranean and semiarid. It was hypothesized that seasonal agricultural activities affect the transport of dust particles with pesticides. The research methods included qualitative and quantitative analyses of pesticides in a hierarchy of distances from agriculture fields into natural and nearby. The renewal of the results indicated that seasonal agricultural activity leading to the transport of dust particles was a major contribution to the spatial distribution of pesticides, in both climate zones. Here we reveal results that must be an essential principle in the use of pesticides in agricultural fields, especially in nearby uninhabited areas. [ABSTRACT FROM AUTHOR]

This study aimed to identify the epicenter and co-occurrence factors of dust storm waves in Kermanshah from 16 to 18 June 2016. To investigate the synoptic conditions of the causes of this phenomenon, data set with a resolution of 0.125º arcs from the European Center for Medium-Term Atmospheric Prediction (ESMWF), including geopotential height at 500 hPa, omega at 700 hPa, sea level pressure, orbital components and meridian at 300 hPa level, specific moisture at 700 hPa level, soil moisture up to 10 cm depth and dust optical depth were used. To route, the origin of dust particles, the Lagrangian method of the HYSPLIT model was used 48 hours before the occurrence of dust phenomenon in Kermanshah at three altitude levels of 200, 1000, and 1500 m. The dust storm was also simulated using WRF-chem numerical weather forecasting model. Finally, through the processing of MODIS satellite images, its scope was determined. Examination of HYSPLIT tracking maps showed that the central and western deserts of Iraq and the Syrian are the main sources of dust for the study area. In synoptic conditions, simultaneously with the occurrence of rising dust, cyclonic systems play a significant role in the transmission of this phenomenon. Significant strengthening of the Iraqi low-pressure system along with the formation of traffic in the Zagros mountains has caused the creation and transfer of dust in the warm period of the year to the study area. The spatial distribution of the dust interpreted by the MODIS images is consistent with the spatial distribution of the dust concentration simulated by the WRF-chem model.

Several sandstorms occured in northern China in early 2021, especially the rare serious one on March 15. The maximum hourly mean concentrations of PM10 in three sandstorm processes in Beijing reached 7506, 2567, and 1456 μg/m3, respectively. The maximum daily mean concentration of PM10 reached 1630 μg/m3. Consecutive days of high PM10 concentrations in mid-to-late March led to the monthly mean concentration exceeding 150 μg/m3 for the first time since 2017, and it also to be the highest monthly mean concentration in recent years. Air mass transport analysis results showed that the strong uplift of dust particles from desertification areas and the long-range transport of dust particles should be the important reasons for the outbreak of large-scale serious sandstorms. The development and eastward movement of the Mongolian cyclone should be mainly responsible for the sandstorms on March 15 and 28. The desertification in Mongolia should be an important cause of these two serious sandstorms. And the arid areas in northern China might have contributed to the intensification of the sandstorms. The arid areas in southern Mongolia and northern Inner Mongolia might be important sources of dust particles for the sandstorm on April 15. [ABSTRACT FROM AUTHOR]

The present study investigates the heat transfer and flow behaviour of magnetohydrodynamic dusty-nano- and dusty-hybrid nanoliquids caused by the stretched surface. We considered the copper oxide (CuO) and magnesium oxide (MgO) nanoparticle suspension in water (H2O) as the base liquid. Similarity transformations are used to transform the partial differential equations to ordinary differential equations and solved by the Runge-Kutta Fehlberg 45 method with a shooting procedure. Outcomes of the velocity and thermal gradients for diverse physical impacts are depicted via plots and the skin friction factor and heat transfer rate are illustrated via tabulated values. Results reveal that dusty-hybrid nanoliquids and their conductive properties play an important role throughout the study. A growth in the mass concentration of dust particles augments the temperature and the Nusselt number, but the reverse reaction to the friction factor and velocity profile has been seen. The Eckert number has a propensity to magnify the temperature of the fluid phase and dust phase. The interaction of dust and nanoparticles extends to the greater heat transmission in the dust phase associated with the fluid phase. Hybridization showed a positive response in the heat transmission of the nanoliquid. The dusty hybrid-nano liquid shows higher heat dispersion compared to the dusty nanoliquid. [ABSTRACT FROM AUTHOR]

The simultaneous transport of momentum, dust particles and heat energy is modeled in form of nonlinear problems via conservation equations. The numerical simulations are performed by implementing finite element method (FEM). The numerical experiments are performed as a function of physical parameters. The relaxation phenomenon and its role in transportation of momentum and heat energy is investigated and an enhancement of transport of heat energy in Maxwell fluid. The velocity of fluid is an increasing function of mixed convection parameter while via hybrid nanostructures Buoyancy force assists the flow. Further, fluid velocity interaction parameter plays a key role in decelerating the flow of fluid with mono and hybrid nano-structures. The ratio of specific heat parameter plays a key role in reducing the temperature of dust particles. Momentum relaxation time determines memory effects and restoration of original state of fluid causes a significant role for decreasing the flow of fluid and hence boundary layer thickness.

Background and Objective: The aim of this study was to investigate dust origin particulate (PM2.5) in Mashhad city in a long period of time (2014-2019) based on unhealthy days. Furthermore, changes in meteorological parameters and their relationship with dust storms have also been investigated. Materials and Methods: In order to locate dust pollution hotspots in mashhad air, first, information about unhealthy days of Mashhad city in a 5-year period was obtained from the site of Mashhad Pollutants Monitoring Center and then HYSPLIT model was used to locate air pollution hotspots caused by particulate matter. To verify the results, the outputs obtained from this model were also compared with the DREAM8b model. Results: By examining the meteorological parameters and its relationship with the outputs obtained from THEHYSPLIT and DREAM8b models, the maximum wind speed and relative humidity were obtained in autumn. There was no rainfall in the studied days (19 days) and the highest temperature was related to summer, indicating the relationship between the occurrences of polluted days due to particulate matter less than μ 2.5, wind speed and relative humidity in autumn. The results of the two models showed that the southern and northeastern regions of Mashhad city had the highest source of dust particles during the studied days. Conclusion: Although in previous articles, the origin of dust in Mashhad city was announced outside the geographical boundaries of the province, long-term investigation at low altitude (below 10m) showed that local origin of dust have an essential role in air pollution in Mashhad city under unstable atmospheric conditions. Inappropriate use of agricultural lands and severe changes in land use often in the northern region and implementation of construction projects such as the southern belt of Mashhad city play essential roles in increasing PM2.5 particles in the air of Mashhad. This finding shows the importance of decision making for the implementation of soil stabilization projects etc... at the local level.

Dust particles on a nonconductive surface are known to acquire electric charge and detach from the surface under plasma conditions and/or when affected by ultraviolet radiation. Similar phenomena occur as a result of electrostatic surface cleaning (shedding) as well as in nature, e.g., when observing levitation of dust particles above the lunar surface. A detachment of dust particles from the surface should occur when the electrostatic forces of their repulsion Fc exceed the sum of the gravitation Fg forces and the adhesive van der Waals FvdW forces acting on the particle on a nonconducting surface. However, a paradoxical situation usually arises: the three primary forces of different nature Fc, Fg, and FvdW, acting on a speck of dust with a characteristic size of the order of hundreds or thousands of nanometers, are completely incomparable in magnitude, herewith Fc << Fg << FvdW. In the last decade, numerous attempts have been made to explain how a particle on a nonconducting surface can acquire a charge sufficient for the electrostatic forces that arise to approach the adhesive forces’ values. However, despite some successes, many questions remain unanswered. This article presents a brief analysis of the charge appearance process on a solitary dust speck and a speck lying on the surface. To explain the detachment of dust particles from the surface caused by electrostatic forces and the accumulation of a charge on those particles sufficient for levitation, one should take into account the charge density fluctuations on the surface.

This contribution devotedly analyzes the behaviour of momentum and heat transfer of dust particles micropolar fluid flow due to a vertical permeable cone with suction and variable wall temperature. Homogeneously suspended dust nano-particles is suggested. Non-similar solutions for governing equations are noticed to be exist when the surface temperature varies as a power law with the length measured from the leading edge. Via suitable coordinate transformation the flow governing equations transformed into non-similar boundary layer flow equations. The subsequent nonlinearly system of micropolar liquid and the dust particle phases are solved numerically via an efficient, tridiagonal, iterative, implicit finite difference technique using FORTRAN software. Aspects of distinct emerging variables on the computations (carrier and dust-particle phases of velocity and temperature) are illustrated through tables and drawn graphical, also Nusselt number and shear and couple stresses factor are given as functions of suction variables. Results point out that an increment in the suction variable or the relative density parameter tends to enhance the local Nusselt number. The present computations are validated by favorable comparisons with earlier published data.

Introduction and purpose: During the past decade, the scientific community has noticed the important impacts of suspended dust in the air on climate, human health, the environment, and various socio-economic sectors. The dust concentration has a negative relationship with human health so that the increase of dust concentration leads to an increase in the number of patients with heart and respiratory diseases, and human health is seriously threatened. The undesirable phenomenon of dust storms is one of the natural disasters that affect Zabol city due to its geographical location and proximity to the dried bed of Hamoon wetland. Therefore, this study aimed to investigate the temporal changes in dust concentrations over a 10-year period in Zabol city. Methods: The concentration of dust particles (PM10) was measured using fixed air pollution measuring devices during a period of 10 years from 2009 to 2019. All data were recorded on a daily and annual basis and the variations during this period were examined in this study. The given data were measured and analyzed based on the air quality index in order to evaluate the air quality changes. Results: In this study, the average annual concentration of PM10 has been 405, 425, 451, 659, 532, 152, 222, 196, 170, and 67 μg/m3, respectively, from 2009 to 2019. The highest particle concentration was determined at 4932 µg/m3 in the summer of 2016, which was the result of 120-day storms, the dried bed of Hamoon wetland, and the transfer of dust particles. Conclusion: According to the standard, the concentration of PM10 should not exceed 50 µg/m3; however, this value has reached several times the standard limit and 33 times the standard limit at maximum during the 10-year period.

Lake Urmia, NW Iran, and S Caucasus region, has lost approximately three‐fourth of its water volume resulting in increased exposure of lacustrine deposits. Therefore, the role of Lake Urmia desiccated saline lands on local aerosols and rainwater compositions is still vague. This study investigates the temporal and seasonal patterns of rainwater chemistry from January 2018 to June 2018 (six months) in 13 stations throughout the Lake Urmia basin. The samples collected were analyzed using triple quadrupole inductively coupled plasma mass spectrometry (ICP‐QQQ) and ion chromatography (IC) to measure elemental and ionic concentrations. Then, the Hybrid Single‐Particle Lagrangian Integrated Trajectory model (HYSPLIT) was applied to identify the pathway and contribution of emissions. The results depict that the concentration of elemental and ionic components over different parts of the Lake Urmia basin are significantly different. West and north directions have the highest concentrations of marine ions associated with fewer toxic elements. In contrast, the east and south directions show a high concentration of heavy metal elements and ions. The high level of heavy and toxic elements at the east and south directions indicates that local anthropogenic sources are more influential. The seasonal and monthly variabilities of chemical compositions depict that the highest concentration of Na+, Mg2+, Ca2+, K+, Cl−, Br−, NO3−, Al, Cr, Mn, Fe, and Co were in the spring season and SO42−, NH4+ and NO2− were highest in winter. Seasonal variation for MSA, organic acids (i.e., Pyruvate, Adipate, and Oxalate), Ni, Cu, Zn, V, and Ti were not apparent. Cluster‐mean HYSPLIT backward trajectories results show the most dominant air mass sectors are from W (a: Iraq, Syria, and Arabian deserts; b: Mediterranean Sea; and c: KSA) and NE (the Caspian Sea and its vicinity), contributed to almost 65% and 22%, respectively. These air masses bring a significant quantity of crustal and marine aerosols, respectively. It is inferred that the Lake Urmia dried‐up lakebeds have less impact on the contribution of emissions across the region. Key Points: The Lake Urmia dried‐up lakebeds have less impact on the contribution of emissions across the Caucasus regionThe impact of Arabian deserts emissions on Lake Urmia basin is more evident than itselfThe Lake Urmia basin is more receiver in emissions than emitter across the Middle East [ABSTRACT FROM AUTHOR]