Fine Particulate Materials Research Articles

Spatial and temporal distributions of clay minerals in the central Andaman Sea: Provenances and sedimentary processes over the last 42 kyr

The uplift of the Tibetan Plateau has led to the formation of the world’s largest sediment “source–sink” system in the northeastern Indian Ocean, and seafloor sediments record rich environmental and climatic information during the accumulation process, making it an ideal area to reconstruct past sedimentary processes. To reveal fine sediment provenance and climatic implications, we present a sedimentary reconstruction during the past 42 kyr based on clay mineral analyses of sediments from core ADM-159 retrieved from the central Andaman Sea. The clay minerals mainly consist of illite (I, 27%–47%) and kaolinite (K, 8%–37%) with minor smectite (S, 11%–37%) and chlorite (C, 11%–37%). Provenance analyses show that the illite-dominated clay minerals are mainly derived from terrestrial sources of detrital material input from the Irrawaddy River, indicating a primary supply of fine sediment from Myanmar terrestrial material. Considering the stable sediment provenance, S/K, S/(I+C), and the illite chemical index were chosen to reconstruct the transport pattern of the fine fraction sediment over the last 42 kyr. S/K and S/(I+C) showed relatively consistent trends over time with relatively high values at 32–25 and 15–6 ka BP, indicating a strong supply and transport capacity of fine particulate matter. In contrast, relatively low values of S/K and S/(I+C) occurred at 25–15 ka BP, indicating a relatively weak deposition process of fine sediments in the study area. The trends in S/K and S/(I+C) are roughly consistent with the variations in solar radiation. Together with the illite chemical index, these trends indicate that solar activity controlled the weathering and sedimentation of fine-grained sediments. We also found significant periodicities in our clay mineral records at 25.05 and 0.473–0.477 kyr, suggesting that the parameters of the Earth’s orbit and solar radiation were potential driving mechanisms of the changes in regional climate. Moreover, monsoon precipitation triggered by the movement of the intertropical convergence zone was another important factor controlling the supply and transport of fine particulate matter in the study area, especially the weak precipitation during the last deglacial period and the relatively strong precipitation during the Holocene, so we could draw a conclusion that precipitation during these periods had significant effects on the weathering, erosion, and transport of fine particulate terrestrial materials over the last 42 kyr.

Linear Modeling of Spectra of Fine Particulate Materials: Implications for Compositional Analyses of Primitive Asteroids

AbstractIn this study, we applied a sum to one constraint weighted least squares (STO WLS) model to thermal infrared (TIR) spectra of a suite of primitive asteroid analogs spectrally and volumetrically dominated by fine particulates (<38 μm). Since coarse particulate emissivity spectra combine linearly, deriving compositions from these are fairly straightforward. Across the TIR it is not as straightforward for fine particulate emissivity spectra due to the nonlinear behavior that arises from volumetric scattering between particles when the particle size becomes comparable to the wavelength of light. Using a WLS model, mixed spectra may be deconvolved into areal percentages of each end member which we assume corresponds to their volume percentages. We used a spectral library of pure mineral spectra to model TIR spectra of a suite of physical mixtures and meteorites obtained under ambient (Earth‐like) and simulated asteroid environment (SAE) conditions collected for the OSIRIS‐REx team (Donaldson Hanna et al., 2021, https://doi.org/10.1029/2020JE006624). The STO WLS model underestimated the modal abundances of the dominant mineral phases by ∼25.0 ± 0.1% on average over the full spectral range and ∼22.0 ± 0.4% over a limited spectral range in all of the ambient and SAE physical mixture and meteorite spectra. Minor phases present in the mixtures and meteorites (abundances ≤5%) were typically not modeled. Also, phases not present in the mixtures were commonly selected (∼2 phases on average with an average abundance of ∼25.2 ± 1.9%) to get the best mathematical fit.

Wound Healing Properties and Structural Analysis of Four Geographical Areas’ Natural Clays

Clays are fine particle materials that harden after drying. The difference in their structure is the key to their efficacy and their subsequent application. The current study aims to evaluate the wound healing property of four countries (C1:Iraq, C2:Turkey, C3:Azerbaijan and C4:Russia) clay samples by excision model using Sprague dawley rats also the chemical analysis of the samples was performed using X-ray diffraction (XRD) and X-ray Fluorescence (XRF) methods. Results revealed that the best wound healing activities were given by C1, C3, C4 and C2 respectively with healing percentages (76%, 71%, 62%, and 60%), respectively. XRD results revealed the presence of Calcium carbonate and CalciumMagnesium carbonate in C1, Dolomite and Calcium-Magnesium carbonate in C2, Cobalt Tantalum Sulfide in C3, Finally Quartz and Silicon Oxide in C4. On the other hand, XRF analysis showed the appearance of different major and trace elements with different quantities in each clay type. We conclude that different countries clays enclose wound healing property with diverse ranges and this diversity is due to their chemical and mineral structures.

Retraction Note to: 5g edge computing and hospital built-in cache technology application in the evaluation of elderly post-anesthesia care

PM2.5 can be inhaled by human body through nasal cavity. This kind of material belongs to a fine particle material, and the surface area of fine particle material is relatively large, and the stored harmful substances will be more, which will cause air to be polluted to a great extent. Moreover, the visibility of air is reduced because aerosol and other substances are attached to the surface of PM2.5. This paper mainly studies the sources of urban environmental pollutants and the related aspects of elderly care by edge calculation. Nursing care after anesthesia in the post-sedation care unit some time ago the recuperation room, where patients are accepting consideration and observing their anesthesia for older people from the impacts of sedation. Nursing care incorporates all parts of patient consideration after the medical procedure. The consideration incorporates pulse, circulatory strain, breath, and breath checking. The boundary value problems of pain comprise of help or using prescriptions, for example, narcotics and mitigating medications to experience effects of need. In the setting of outpatient medical procedures, it would be ideal if they follow the accompanying strides with recuperation room nurture direction and self-care methods for patients.

Hydraulic and Swell–Shrink Characteristics of Clay and Recycled Zeolite Mixtures for Liner Construction in Sustainable Waste Landfill

This paper presents research considering hydraulic as well as swelling and shrinkage characteristics of potential recycled fine particle materials for compacted clay liner for sustainable landfills. Five locally available clay soils mixed with 10% (by mass) of NaP1 recycled zeolite were tested. The performed analysis was based on determined plasticity, cation exchange capacity, coefficient of saturated hydraulic conductivity after compaction, several shrinkage and swelling characteristics as well as, finally, saturated hydraulic conductivity after three cycles of drying and rewetting of tested specimens and the reference samples. The obtained results showed that addition of zeolite to clay soils allowed reduction in their saturated hydraulic conductivity to meet the required threshold (≤1 × 10−9 m/s) of sealing capabilities for compacted clay liner. On the other hand, an increase in plasticity, swelling, and in several cases in shrinkage, of the clay–zeolite mixture was observed. Finally, none of the tested mixtures was able to sustain its sealing capabilities after three cycles of drying and rewetting. Thus, the studied clayey soils mixed with sustainable recycled zeolite were assessed as promising materials for compacted liner construction. However, the liner should be operated carefully to avoid extensive dissication and cracking.

Can Macroinvertebrate Traits Be Explored and Applied in Biomonitoring Riverine Systems Draining Forested Catchments?

Trait-based approach (TBA) in recent time has received tremendous attention as complementary tool over taxonomic-based approach in assessing ecological health of riverine systems in developed countries, but in the Afrotropical region the trait-based approach is still in its infancy. No trait-based approach has been developed for riverine systems draining forested catchment in the Afrotropical region. Hence, this study was conducted to explore and apply macroinvertebrates traits as potential biomonitoring tools in assessing ecological health of riverine systems draining forested catchments in the Niger Delta area of Nigeria. Selected physico-chemical variables were sampled together with macroinvertebrates in 18 stations of 10 riverine systems from 2008 to 2012. The 18 stations were classified into three ecological classes namely near natural stations (NNS), slightly disturbed stations (SDS), and moderately disturbed stations (MDS) using physico-chemical-based classification with the aid of principal component analysis (PCA). The results revealed traits such as possessions of hardshell body armouring, preferences for clear and transparent water and opaque water, climbing and crawling mobility mechanisms, large (>20–40 mm) body size, preferences for scrapping, shredding, and grazing feeding habits to be associated with NNS and SDS based on RLQ (R, physico-chemical variables; L, taxa; Q, traits) analysis performed. Thus, these traits were deemed to be sensitive to human impact in forested systems. Also, traits such as tegument/cutaneous respiration, soft and exposed body armouring, burrowing mobility mechanism, spherical body shape, preference for detritus [fine particulate organic materials (FPOM)] food materials, small (>5–10 mm) body size and preference for filter feeding mechanism were associated with MDS. Hence, they were deemed tolerant of human impact in forested systems. A fourth-corner test performed revealed tegumental/cutaneous respiration preference, soft and exposed body armouring and burrowing mobility mode, which were associated with the MDS on the RLQ ordination were also positively correlated to 5 day biochemical oxygen demand (BOD5); while preference for clear and transparent water, which were positively associated with MDS, were also positively correlated with pH and negatively correlated to dissolved oxygen (DO). Overall, this study affirmed that the TBA can be explored in biomonitoring riverine systems draining forested catchments. Nevertheless, we suggest the trait-based approach to be further explored, with a view to developing trait-informed indices for biomonitoring Afrotropical riverine systems.

Evaluation and control of the adhesiveness of cohesive calcium carbonate particles at high temperatures

Understanding the adhesiveness of fine particulate materials at high temperatures is important to achieving the stable, economical operation of various industrial systems. In the present research, two types of calcium carbonate (CaCO3) particles having different mean particle sizes (often used as heat carriers in energy systems) were evaluated. The tensile strengths of beds of these materials were determined at various temperatures by tensile strength measurement tester. The adhesiveness was found to increase greatly at 500 °C even without chemical reactions or sintering, and X-ray diffraction analyses showed thermal expansion of the CaCO3 crystals at 500 °C. Pure alumina (Al2O3) and silica (SiO2) microparticles did not exhibit the same pronounced increases in tensile strength or crystal expansion at this same temperature. Because the surface distances between these primary particles were presumably small, it is proposed that van der Waals forces between the particles greatly increased at high temperatures. The addition of Al2O3 nanoparticles to the CaCO3 decreased the tensile strengths of the powder beds both at ambient temperature and at 500 °C. The experimental data confirm that the surface distances between primary particles were increased upon incorporating the nanoparticles, such that the tensile strength decreased during heat treatment.

Dry separation of fine particulate sand mixture based on density-segregation in a vibro-fluidized bed

Separation of fine particulate solid materials is one of most important unit operations in industry. Utilization of gas-solid fluidized beds has been considered where particulates are released from constraints due to contacts with surrounding particulates and segregation occurs according to density, size or combination of density and size. Addition of mechanical vibration to the gas-solid fluidized bed may improve dry solid separation. In this study, we investigated the dry separation characteristics of solid particulates using a vibro-fluidized bed especially focusing on the separation of fine particulate ores (≈100 μm) with small density differences. At first, we focused on the influence of fluidizing air velocity on the efficiency of segregation. Subsequently, the influence of vibration strength, vibration amplitude and frequency on segregation behavior was investigated. We found the density segregation does not occur with either gas-fluidization or vertical vibration alone. Only the combination of these effects produces density segregation. The fluidizing air velocity is an important factor to enhance the density-segregation of the particulates with small density difference.

Emission Characteristics of Major Atmospheric Pollutants in Changchun City

Based on the technical guide for the preparation of air pollutant emission inventory, this paper makes a statistical analysis of the basic data of air pollution related to the Changchun, and according to the relevant literatures, establishes a list of the main air pollutant emissions from the Changchun 2016 air pollution emission sources (including fine particles, sulfur dioxide and nitrogen oxides). Then the uncertainty analysis is made by Monte Carlo method, and the countermeasures of Changchun air pollution control are put forward. The results showed that the total emission of PM_2.5 in Changchun in 2016 was 70986.45t, and the emissions from the main sources are fixed combustion source, mobile source, process source, biomass burning source and dust source respectively. According to the analysis, we know that coal-based energy consumption structure not only contributes significantly to the emission of one fine particulate matter, but also emits a large number of two fine particulate precursor materials, such as sulfur dioxide, nitrogen oxides. The total sulfur dioxide emission in Changchun in 2016 is 52183.55t, and the total NOx emission is 13.15 million tons. The uncertainty analysis of the Monte Carlo method shows that the uncertainty range of the emission inventory is small and the estimation results are quite credible.

Production of Fine Particle Materials with High Performance by Microreactor

Production of Fine Particle Materials with High Performance by Microreactor

Technical Terms Related to the Feature Articles: Synthesis Technologies of Functional Fine Particle Materials and Their Applications

Technical Terms Related to the Feature Articles: Synthesis Technologies of Functional Fine Particle Materials and Their Applications

Introduction to the Feature Articles: Synthesis Technologies of Functional Fine Particle Materials and Their Applications

Introduction to the Feature Articles: Synthesis Technologies of Functional Fine Particle Materials and Their Applications

Short Communication: The clay nanoparticle impregnation for increasing the strength and quality of sengon (Paraserianthes falcataria) and white meranti (Shorea bracteolata) timber

Alex T, Winarni B, Kusuma IW, Arung ET, Budiarso E. 2017. Short Communication: The clay nanoparticle impregnation for increasing the strength and quality of sengon (Paraserianthes falcataria) and white meranti (Shorea bracteolata) timber. Nusantara Bioscience 9: 107-110. The clay nanoparticle impregnation for increasing the strength and quality of sengon (Paraserianthes falcataria) and white meranti (Shorea bracteolata) timber. The clay nanoparticles as a fine particle material dissolved in water was impregnated into the sengon and white meranti timber in order to improve its strength properties. Impregnation is the process of inserting the material dissolved in specific water or liquid in the timber using vacuum tube and air pressure. Materials used in this study were clay nanoparticles and the sample test of sengon (P. falcataria) and white meranti (S.bracteolata) timbers with a size of 2 cm x 2 cm x 40 cm. A total of 30 samples for each type of dried timber were impregnated using clay nanoparticles with a pressure of 60 psi for 2 hours. The results showed that impregnation with clay nanoparticles at concentrations of 5% gave the retention value of sengon and white meranti timber of 22.73 kg.m3 and 24.89 kg.m3, respectively. Wood strength is indicated by the voltage value at the boundary proportion (SPL), modulus of rupture (MOR) and modulus of elasticity (MOE). sengon timber shows the value of SPL, MOR, MOE by 296.57 kg.cm2, 376.36 kg.cm2, and 38027.663 kg.cm2, while the white meranti timber had the value of SPL, MOR, MOE as follows: 623, 32 kg.cm2, 729.69 kg.cm2 and 160.187 kg.cm2. The strength of sengon timber was increased from class V (very low) to class IV (low), whereas white meranti was increased from class IV (low) into class II (strong).

Development of two fine particulate matter standard reference materials (

Two new Standard Reference Materials (SRMs), SRM 2786 Fine Particulate Matter (<4μm) and SRM 2787 Fine Particulate Matter (<10μm) have been developed in support of the US Environmental Protection Agency's National Ambient Air Quality Standards for particulate matter (PM). These materials have been characterized for the mass fractions of selected polycyclic aromatic hydrocarbons (PAHs), nitrated PAHs, brominated diphenyl ether (BDE) congeners, hexabromocyclododecane (HBCD) isomers, sugars, polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners, and inorganic constituents, as well as particle-size characteristics. These materials are the first Certified Reference Materials available to support measurements of both organic and inorganic constituents in fine PM. In addition, values for PAHs are available for RM 8785 Air Particulate Matter on Filter Media. As such, these SRMs will be useful as quality control samples for ensuring compatibility of results among PM monitoring studies and will fill a void to assess the accuracy of analytical methods used in these studies. Graphical Abstract Removal of PM from filter for the preparation of SRM 2786 Fine Particulate Matter.

Mathematical and empirical description of screen blocking

This paper addresses the process of sieve holes blocking taking place while screening fine-particulate materials and provides an analytical description of the phenomenon. Empirical tests performed as part of this research provided dependences specifying the parameters of sieve holes blocking that could be applied in practice. The process of sieve holes blocking is unfavourable and inevitable. It is related with the screen clearance coefficient which is one of the fundamental characteristics of all screens. The grains whose dimensions are similar to the dimensions of the sieve holes block those holes, causing their exclusion from the active surface area of the screen. This phenomenon results in diminished performance and efficiency of the screening process. Screening is a very common industrial practice, and various designs of screens and types of sieves are available. That is why the subject of this paper is so important. The screen blocking coefficient is the measure of sieve holes blocking. In order to describe the process of screen blocking, a mathematical model is presented and a method for determining the screen blocking coefficient is proposed. Furthermore, the authors list the factors that have a significant influence on the degree of sieve holes blocking, i.e. the shape of the screened material, the toss indicator and the content of hard-to-screen grains in the feed. This paper is the first one to have thoroughly described the issue of screen blocking.

Synthesis of Fine Particle Materials for Solid Oxide Fuel Cell by Aerosol Processing

Synthesis of Fine Particle Materials for Solid Oxide Fuel Cell by Aerosol Processing

Phase formation processes in the NiO-CuO-Fe2O3-Cr2O3 system upon salt decomposition

This paper presents a comparative evaluation of phase formation in the NiO-CuO-Fe2O3-Cr2O3 system during salt decomposition reactions. A spinel phase has been shown to form in all of the materials studied. The structure of the compounds obtained has been investigated by X-ray diffraction and low-temperature nitrogen adsorption measurements. The results demonstrate that synthesis in the presence of an organic precursor allows fine-particle spinel materials to be obtained.

Introduction to the Feature Articles: Aerosol Synthesized Fine Particle Materials and Their Application toward Environmental Energy Materials

<b>Introduction to the Feature Articles: Aerosol Synthesized Fine Particle Materials and Their Application toward Environmental Energy Materials </b>

The dual nature of the martian crust: Young lavas and old clastic materials

Visible and thermal infrared spacecraft datasets are used to gain insight into the nature of the surface materials and upper martian crust, revealing a distinct transition in the physical properties of martian crustal materials that occurred during the Hesperian era. Contrary to a prevailing view of the martian crust as primarily composed of lava flows, we find that most older regions of Mars have morphological and thermophysical properties consistent with poorly consolidated fine-particulate materials that may have a volcaniclastic origin. By contrast, younger surfaces contain blocky materials and thermophysical properties consistent with effusive lava flows. Explosive volcanism is likely to have been dominant on early Mars and these findings have implications for the evolution of the volatile content of the crust and mantle and subsequent development of the surface morphology. This dual nature of the crust appears to be a defining characteristic of martian history.

Application of Wet Granulation Processes for Granola Breakfast Cereal Production

The present review discusses the attributes of granola breakfast cereal produced by wet granulation. Granola is an aggregated baked food product often eaten as a breakfast cereal containing natural ingredients such as oats, nuts and honey. Wet granulation is a unit operation where fine primary particulate materials (powders, grains etc.) agglomerate in the presence of a liquid binder to produce larger granules. High-shear granulation and fluidised bed granulation are the most common mode of wet granulation. Granulation prevents the segregation of co-agglomerated components, resulting in an improvement in content uniformity. In addition, the compression and dissolution characteristics, product attractiveness of the product are improved. The granulation process and operation conditions are discussed in detail and a case study employing granola production is presented.