Dust Particles Research Articles

Proposal for a Quick Method for Choosing Plant Species to Accelerate Pedogenesis on Waste Dumps

Abstract Mining is one of the activities that require large areas of land for the storage of sterile rocks resulting from the extraction of useful mineral substances. Waste dumps are wide-spread, are unpleasant components of the landscape causing a negative visual impact, the modification of ecosystems and their functions, environmental pollution (depending on their content, it can result atmospheric pollution by entrainment of dust particles and powders by winds, generation of acid waters, land and soil pollution with trace elements, etc.), and may present risks for the objectives in the area as a result of the sliding potential. The waste dumps consisting of inert rocks like sands, clays, and dust in different mixtures, which present various degrees of aeration and permeability and which lack the fertility given by organic matter, need proper interventions and works to support the development of more valuable plants and to reintegrate them into the natural landscape. The research presented in this paper aims to identify the necessary steps in order to accelerate the pedogenesis process on mining dumps and, as a result, a logical scheme type method was developed that could be easily applied to any type of mining dump. Also, the logical scheme was applied and verified through an experimental study carried out at the level of the interior dump of North Pesteana open-pit from Rovinari mining basin, Romania.

Utilizing Waste Engine Oil and Soft Binder as Additives to Mitigate the Moisture Damage of Asphalt Mixtures

The deterioration of asphalt pavements caused by moisture is a significant concern for asphalt pavement construction companies. To improve this characteristic, this research aims to determine how rejuvenators and flexible compounds, affect the resistance of asphalt concrete to moisture. This study investigates the effects of incorporating Waste Engine Oil (WEO), an easily obtainable and economical substance, into a maturing mixture. The action of this substance resulted in strengthening the physical and chemical characteristics of the bitumen, as well as mitigating the adverse effects caused by moisture. The various degrees of bitumen penetration ranged from 40-50 to 80-1. Extremely small limestone dust particles measuring 19.0 mm, were utilized as mineral infill in the aggregate grade. To enhance the Marshall characteristics, treatments containing 0%, 2%, 4%, and 6% WEO by weight of binder were implemented after filtration. The most advanced Marshall had a WEO content of 6% and an asphalt grade ranging from 85-100, while stability and resistance to moisture degradation were observed. Compared to combinations lacking WEO, the compressive strength and the indirect tensile strength value, were determined to find the Index of Retained Strength (IRS) and Tensile Strength Ratio (TSR). This reduced moisture susceptibility as TSR% and IRS% values increased by approximately 1.22% and 0.9%, respectively.

Experimental study on the concentration fluctuation of dust particles with different sizes during a dust storm

Experimental study on the concentration fluctuation of dust particles with different sizes during a dust storm

Use of electron microscopy to determine presence of coal dust in a neighborhood bordering an open-air coal terminal in Curtis Bay, Baltimore, Maryland, USA

Despite decreasing US consumption, over 90 million metric tons of coal were exported by the US in 2023, requiring significant infrastructure for transport, handling, and storage of coal at export terminals. Residents in Curtis Bay, Baltimore, Maryland, USA live at the fenceline of an open-air coal terminal and have, for decades, reported rapid accumulation of black dust at their homes. Community-level exposure to coal dust originating from coal handling and storage terminals has remained largely unexplored. To investigate community-identified concerns and use a community-driven approach to determine the presence/absence of coal dust on Curtis Bay surfaces. Passive settled dust samples were collected from two residential areas, 345m and 1235m from the coal terminal, using conductive carbon tape. Scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDX) of standard reference coal material and positive control material from the coal terminal in Curtis Bay were used to optimize the morphological and elemental classification criteria for coal dust. A manual SEM-EDX protocol was developed to identify coal particles in settled dust collected on conductive carbon tape in community settings. SEM-EDX analysis confirmed presence of coal dust sampled at both residential locations. Estimated coal dust particle loading at the proximal and distal site were 13.2 and 3.4 coal particles/mm2, respectively. The coal dust particles identified met specific criteria, including size (>5μm), morphology, and elemental composition (≥75% carbon, ≤20% oxygen). These findings are consistent with longstanding community concerns and lived experiences regarding the presence of coal dust in Curtis Bay, which neighbors a major open-air coal terminal. This approach has potential for other communities neighboring coal terminals to assess similar concerns with residential coal dust exposure.

Kinetic field theory applied to planetesimal formation I: Freely streaming dust particles

Abstract Planet formation in the solar system was started when the first planetesimals were formed from the gravitational collapse of pebble clouds. Numerical simulations of this process, especially in the framework of streaming instability, produce various power laws for the initial mass function for planetesimals. While recent advances have shed light on turbulence and its role in particle clustering, a comprehensive theoretical framework linking turbulence characteristics to particle cluster properties and planetesimal mass function remains incomplete. Recently, a kinetic field theory for ensembles of point-like classical particles in or out of equilibrium has been applied to cosmic structure formation. This theory encodes the dynamics of a classical particle ensemble by a generating functional specified by the initial probability distribution of particles in phase space and their equations of motion. Here, we apply kinetic field theory to planetesimal formation. A model for the initial probability distribution of dust particles in phase space is obtained from a quasi-initial state for a three-dimensional streaming-instability simulation that is a particle distribution with velocities for gas and particles from the Nakagawa relations. The equations of motion are chosen for the simplest case of freely streaming particles. We calculate the non-linearly evolved density power spectrum of dust particles and find that it develops a universal k−3 tail at small scales, suggesting scale-invariant structure formation below a characteristic and time-dependent length scale. Thus, the KFT analysis indicates that the initial state for streaming instability simulations does not impose a constraint on structure evolution during planetesimal formation.

Frequency of Respiratory Symptoms among Marble Workers in Cutting and Grinding sections of Marble Factories, Lahore

Occupational exposure to dust particles was a public health problem in developing countries. One of the main dust which is responsible for higher prevalence of obstructive lung diseases is silica dust present in marble factories. Objective: To compare the frequency of respiratory symptoms among individuals working in cutting and grinding sections of marble factories, Lahore. Methods: A cross sectional study was conducted in marble factories situated in Ichra market, Ferozepur Road Lahore, during April to September 2022. Forty-one marble employees each from wet cutting and dry grinding sections were selected after obtaining written consent from the respondents. Data were collected in a pretested standardized questionnaire regarding socio demographic and respiratory symptoms. The data were analyzed by SPSS version 24.0. Results: The mean age of workers was 29.93 ± 6.18 years while mean years of work experience was11.19 ± 5.66 years. 20 (48.78%) workers of dry cutting had cough as compared to 14 (34.14%) workers of wet cutting section. Similarly, 11 (26.8%) workers of grinding section had experienced phlegm whereas 6 (14.63%) from wet cutting workers complained of this symptom. Similarly, breathlessness and chest tightness were more prevalent among grinding workers as compared to marble cutting workers showing statistically significant association (p-value < 0.005). Greater than 15 years of work exposure, respiratory symptoms were significantly (p-value < 0.001) more common in grinding workers than in cutting workers. Conclusion: Respiratory symptoms were more marked among grinding workers than among wet cuttings workers.

Recent progress of soiling impact on solar panels and its mitigation strategies: A review

Recent progress of soiling impact on solar panels and its mitigation strategies: A review

Origins and Aging of Calcium-rich Mineral Particles in Asian Dust Arriving in Southwestern Japan: A Comparison of Slow- and Fast-moving Events

Origins and Aging of Calcium-rich Mineral Particles in Asian Dust Arriving in Southwestern Japan: A Comparison of Slow- and Fast-moving Events

Hygienic assessment of the potential danger of exposure to fine particles and rare earth elements present in the workplace air for workers at metallurgical enterprises

Introduction. One of the main air pollutants in the working area of metallurgical enterprises is rare earth elements, which are sorbed on fine dust particles and have a negative impact on the health of workers. The study aims to carry out a comprehensive hygienic assessment of the potential health hazards of fine particles and rare earth elements (REE) contained in the air of the working area at metallurgical enterprises. Materials and methods. The specialists have took samples of the working area air to measure the content of REE, dust and industrial aerosol of small fractions, they have assessed the levels of REE in the blood of employees of the metallurgical enterprise (n=31) and the comparison group (n=12). The scientists have measured the REE content in the air of the working area and blood using inductively coupled plasma mass spectrometry on an Agilent 7900 mass spectrometer. The authors have measured the dust content in the air of the working area in accordance with the MUK 4.1.2468-09 method and determined the content of fine fractions of industrial aerosol using the DustTrak 8533 aerosol analyzer. Results. Analysis of the metal content in the air of the working area showed an excess of control concentrations for chronic inhalation exposure to cerium. In points with a high concentration of metals, the content of industrial aerosol of a fine fraction of 10 microns prevails. During the study of the work area, experts found significantly higher concentrations in the blood of workers employed in production, compared with the comparison group. Limitations. The limitation of research is due to the period of sampling of the working area air, insufficient number of samples of the working area air and samples of biomaterial. The expansion of the list of surveyed points in production and the list of metallurgical enterprises, as well as an increase in the number of surveyed workers, may become a direction for further research to assess the impact of fine particles and rare earth elements on workers of metallurgical enterprises. Conclusion. Since higher concentrations of REE were found in the air of the work area and in the blood of workers compared to the control point/group, reducing the impact of harmful production factors of working conditions and production processes in order to preserve the health of workers remains relevant for enterprises of the metallurgical industry. Ethics. The study was conducted in compliance with Ethical standards in accordance with the Ethical principles set out in the Helsinki Declaration of the World Medical Association (ed. 2013). The study was approved by the local Ethical Committee of the Federal Scientific Center for Medical and Preventive Technologies for Public Health Risk Management of Rospotrebnadzor (meeting protocol No. 2 dated 02/11/2021).

Myricetin Alleviates Silica-Mediated Lung Fibrosis via PPARγ-PGC-1α Loop and Suppressing Mitochondrial Senescence in Epithelial Cells.

Long-term inhalation of silica dust particles leads to lung tissue fibrosis, resulting in impaired gas exchange and increased mortality. Silica inhalation triggers the aging of epithelial cells (AECs), which is a key contributor to the development of pulmonary fibrosis. Myricetin, a flavonoid compound extracted from Myrica genus plants, possesses various biological activities, including antioxidant and immunomodulatory effects. However, the mechanisms underlying myricetin's ability to counter senescence and fibrosis need to be further studied. In vivo, the antifibrotic and anti-senescence effects of myricetin were evaluated using a silica-induced pulmonary fibrosis mouse model. To further elucidate the mechanisms by which myricetin counteracts silica-induced senescence, in vitro experiments were conducted using AECs. Our studies revealed that myricetin treatment alleviated silica-induced mortality, improved lung function, and reduced the severity of pulmonary fibrosis in mice. Immunofluorescence analysis suggests its potential in mitigating senescence of AECs. Under laboratory conditions, myricetin intervened in the cellular senescence pathway induced by silica dust by modulating mitochondrial function. It acted through the PPARγ-PGC1α axis, effectively reducing silica-induced mitochondrial oxidative stress in AECs, promoting mitophagy, and maintaining mitochondrial dynamics. However, the efficacy of myricetin was reversed under PPARγ siRNA intervention. Additionally, myricetin exhibited an enhancing effect on PPARγ and autophagy in animal models. Treatment with PPARγ and PGC-1α siRNA elucidated the role of myricetin in promoting the formation of a positive feedback loop between PPARγ and PGC-1α. Additionally, the PPARγ inhibitor GW9662 verified the in vivo effects of myricetin. Myricetin activates PPARγ, forming a PPARγ-PGC-1α loop, which promotes mitophagy and maintains mitochondrial dynamics. This alleviates epithelial cell senescence induced by silica exposure, consequently mitigating silica-induced pulmonary fibrosis in mice.

Impact of Anthropogenic Factors on the Diversity of Microbial Communities of PM10 Air and PM100 of Tilia L. Phylloplane in an Urban Ecosystem.

Identifying the relationship between the microbiomes of urban dust particles from different biotopes is important because the state of microorganisms can be used to assess the quality of the environment. The aim of this work was to determine the distribution and interaction patterns of microorganisms of dust particles in the air and on leaf surfaces. Metabarcoding of bacterial and fungal communities, PAH, and metal content analyses and electron microscopy were used in this work. The results obtained allowed us to characterise the biological and chemical components of the dust particles. Some bacterial and fungal genera were correlated with benzanthracene, fluoranthene, and Cu, Ni, Co, Zn, and Mn contents. Bacterial communities were found to be more sensitive to all the pollutants studied. PM10 microbial communities circulated between biotopes and study areas due to air flows, as evidenced by the presence of similar ASVs in fungi and bacteria. The results could help to understand the effects of climate change and anthropogenic activities.

Fabrication and property evaluation of waste glass dust filled epoxy‐hemp and epoxy‐flax hybrid composites

AbstractGlass dust particles, generated in glass cutting industries as a process waste possess health risk and serious environmental issues. This paper essentially reports on exploring the possibility of using this waste glass dust as particulate filler in two different natural fibers (hemp/flax) reinforced polymer composites. Such composites are prepared by hand lay‐up route, varying weight percentages of waste glass dust from 0 to 20. The physical and mechanical characterizations are evaluated experimentally. X‐ray diffractogram analysis reveals the degree of crystallinity of the composites and the phases present in the raw filler. With the incorporation of waste glass dust, the flexural strength, inter‐laminar shear stress and micro‐hardness of the composites are improved up to about 52 %, 44 % and 20 % respectively. On the contrary, tensile and impact strengths tend to decrease about 32 % and 17 % with filler content. Using scanning electron microscopy, the possible mechanisms such as fiber‐matrix de‐bonding, fiber‐pullout, matrix crack and rupture etc. are identified for failures of the composites under tensile, flexural and impact loadings. With low crystallinity and fairly good mechanical properties, these hybrid composites can have potential use in thermal insulations and low‐load engineering applications.

Modeling the interstellar dust detections by DESTINY[formula omitted] I: Instrumental constraints and detectability of organic compounds

Modeling the interstellar dust detections by DESTINY[formula omitted] I: Instrumental constraints and detectability of organic compounds

Synergy of chelating agents and surfactants on the wettability and pore structure of coal dust: Experimental study and molecular simulation

Synergy of chelating agents and surfactants on the wettability and pore structure of coal dust: Experimental study and molecular simulation

Dominating Remote Source and Its Potential Contribution of Airborne Dust Over the Tibetan Plateau.

Dust particles, transported over long-distances and driven by westerly winds, dominate high-altitude (>4km) snow darkening and melting over the Tibetan Plateau (TP). A systematic assessment of their remote sources and potential contributions remains limited. In this paper, we present a novel algorithm for source-tracing of airborne dust designed to tackle the aforementioned challenges. The algorithm effectively constrains dust activity and guarantees precise tracking through using satellite and reanalysis-based estimates. The high-altitude airborne dust over the TP shows considerable spatial variation and primarily comes from the desert clusters in Central Asia, West Asia, and South Asia. The Karakum, Taklimakan, and Thar deserts are significant sources of high-altitude airborne dust in the northwest, northeast, and southwest regions of TP, with average mass loadings (mg m-2) contributing rates of 42.2% (32.9), 49.6% (48.3), and 16.4% (32.1), respectively. The results demonstrate significant differences in how adjacent deserts affect high-altitude snowmelt in the TP.

Self‐Organization of Relaxed Structures in the Lunar Atmosphere

ABSTRACTThe study investigates the relaxation of a three‐component dusty plasma in the lunar atmosphere. By employing Ampère's law with momentum balance equation of the plasma species, which includes an electron, a positive ion, and a negatively charged dust particle, a Triple Beltrami (TB) state is obtained. This TB state is characterized by three scale parameters, which may be real or complex. The Cartesian coordinate geometry is employed to analyze the magnetic field profiles. The Beltrami parameters, mass of negative charged dust particulates and density variations at different height and angle have a significant impact on the magnetic properties of the self‐organized structures in lunar atmosphere. The study reveals that all scale parameters associated with diamagnetic structures are real and complex, while all scale parameters for paramagnetic structures are real. It has been shown that the magnetic field, along with its complex conjugate and real part, increases with height and angle, and only diamagnetic structures are formed in the lunar atmosphere. The findings of this study should help to explain relaxed structures found in other astronomical objects and in lab settings including negatively charged dust particles, ions, and electrons.

Influence of Higher Order Chemical Reaction on Rotational and Permeable Radiative Flow with Interruption of Micro-organism

Objective: The concentration on the function of the non-Newtonian radiative Casson Nanofluid model via a permeable and stretchable cone has been investigated. The innovation of the problem is Casson, taken as base fluid, and Manganese Ferrite is dropped in the base fluid under the action of a higher-order chemical reaction. This study examines the convective magneto-hydrodynamic (MHD) flow of a conducting micro-organism fluid confined within a horizontal channel via stimulus of a transverse magnetic field (MHD) and thermal radiation parameter. Methods: The foremost partial differential equations (PDE) are changed into an arrangement of ordinary differential equations by applying adequate corresponding transform. The outputs of these equations are performed numerically employing the RK method and computed by well-established BVP4C MATLAB software Special features such as radiation, heat generation/absorption, Joule heating, and electrically conductive MHD are examined. Skin friction and Nusselt number are incorporated into the flow and results are tabulated and outcomes are discussed graphically. Findings: The system incorporates the effects of micro-organism, pressure gradient and the movement of the moving cone. The generated heat is significant enough to cause radiation from both the fluid and the dust particles. Solutions for velocity and temperature distributions of the fluid, as well as the velocity and energy of the dust particles, are obtained using a perturbation scheme. The analytical impact of numerous geometrical parameters on both fluid and dust particle profiles has been analyzed and illustrated graphically. The impact of nonlinear partial derivative formulations is developed subjected to boundary layer theory. Novelty: As labelled in the results, heterogeneous is the examination of thermal radiation in science and technology such as liquid metal fluids different momentum devices for missiles, and turbines of gas effects on thermal radiation are exhibited and distinguished in various investigations and mathematical applications uses of the view in which radiant production be dependent on temperature are point out as a new value to the prevailing literature. Keywords: Thermal radiation, Brownian motion, Buoyancy flow, Chemical reaction, Heat and Mass transfer, Rotating cone

Flotation Enrichment of Micro- and Nanosilica Formed During the Production of Silicon and Ferrosilicon

This paper presents the results of experiments conducted on the flotation separation of cyclone dust particles. The flotation process was conducted using a laboratory flotation apparatus comprising three chambers. Experimental tests supported theoretical results of the theoretical reasoning and justification for the choice of parameters that the flotation process should have in order to extract particles of such small sizes. Furthermore, this work elucidates the concept of “nanobubbles” and substantiates their viability for use in the flotation of nanoparticles, given that bubbles of such a magnitude are firmly affixed to the hydrophobic surface of particles. Bubbles of a larger size than nanoparticles will float both hydrophobic and hydrophilic particles. The effective flotation of cyclone dust from the gas cleaning of silicon and ferroalloy production provided two materials as a result. The experiments yielded insights into the rational technological parameters of the flotation mode for obtaining new products. These insights were gleaned from the preliminary conditioning (conditioning time from 0.5 to 1.5 h) of wet cyclone dust (dry dust weight of 4 kg) with liquid glass (1.4 g per 1 dm3 of pulp) in a cavitation unit at a pH value of 8.5. The flotation process was conducted in a three-chamber flotation apparatus with a volume of 0.02 m3 for a duration of 90 min, utilizing a pneumohydraulic aerator with air suction from the atmosphere. In this instance, the pulp was conveyed via a pump at a pressure of 0.4 MPa from the initial cleansing chamber into the aerator. During the flotation process, kerosene (1 mg per 1 dm3 of pulp) and pine oil (2 mg per 1 dm3 of pulp) were added as additives. The resulting products were silicon dioxide (95%) and carbon nanoparticles (94%).

What is the amount of baryonic dark matter in galaxies?

What is the amount of baryonic dark matter in galaxies?

Captured molecules could make a Bose star visible

A Bose star passing through cold molecular clouds may capture atoms, molecules, and dust particles. The observational signature of such an event would be a relatively small amount of matter that is gravitationally bound. This binding may actually be provided by invisible dark matter forming the Bose star. We may expect a relative excess of heavier atoms, molecules, and solid dust compared to the content of giant cold molecular clouds since the velocity of heavy particles at a given temperature is lower and it may be small compared to the escape velocity, vrms=3kBT/mgas≪vesc=2GM/R. Finally, the velocity of this captured matter cloud may correlate with the expected velocity of free dark matter particles (e.g., expected axion wind velocity relative to Earth). Published by the American Physical Society 2024