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Determining the particle size distribution of water mist is necessary for a wide range of industrial applications or experimental measurements. Particle size defines the ability of water mist to absorb heat, absorb or scatter heat radiation, inertize the environment, reduce environmental dust, regulate odor, etc. The paper presents the principle of measuring droplet size distribution using laser diffraction and the measurement procedure for four hollow cone water mist nozzles with orifice 400 µm, 500 µm, 600 µm and 1000 µm. The measurements were performed at distances of 25 mm, 50 mm, 75 mm, 100 mm, 125 mm, 150 mm, 175 mm, 200 mm and 225 mm from the orifice of the individual nozzles in the middle of the water mist cone. Further measurements were made 25 mm, 50 mm and 75 mm from the nozzle orifices on the edge of the fog cones. All measurements were performed at a working pressure of 70 bar in a water mist system. [ABSTRACT FROM AUTHOR]

Hygroscopic nature of alkali metal chloride salts makes attaining mono-sized dried particles from their aqueous precursor solution an engineering challenge for conventional co-current or counter-current spray driers. Conventional spray driers offer better thermal utilization in either the spray zone or dried particle zone depending on their configuration viz. co-current or counter-current, respectively. In this work, an alternative prototype named induction heating based pulsed spray drier (IH-PSD) is proposed to obtain dry alkali metal chloride salt powders with narrow particle size distribution. Laser diffraction analysis is carried out for initial droplet size distribution whereas scanning electron microscopy and sieve shaker analysis is carried out for studying the particle morphology and particle size distribution of dried powder for all the selected salts. The resultant particle properties emphasized in the present work are the dried particle to initial droplet diameter ratio and the wet basis moisture content. It has been observed that the ratio of mean volume diameter of dried particle to sauter mean diameter of initial droplet lies in the range of 0.4–3.6 meanwhile the wet basis moisture content of dried powder lies in the range of 1.4–3.6 for the selected salts. Artificial neural network (ANN) model is applied for inferring the influence of IHPSD process parameters on the above mentioned dried particle properties and satisfactory convergence with experimental values has been achieved. Comparative plot for experimental and ANN predicted values of dried particle to droplet diameter ratio d 43 p d 32 sol [-] and wet basis dried particle moisture content χ w p [ % ] of alkali metal chloride salts in induction heating based pulsed drier (IH-PSD) prototype. HIGHLIGHTS: Spray drying prototype coupled with Induction heating and mechanical pulsation Scanning electron microscopy for morphological study of spray dried particle Laser diffraction for initial droplet size distribution analysis Sieve shaker experiments for size distribution analysis of spray dried particle Artificial neural network for prediction of droplet to dried particle size ratio [ABSTRACT FROM AUTHOR]

This study was conducted to verify the usefulness of the laser diffractometer method for determining the particle size distribution of selected organic soils from the Podkarpacie region in Poland. The soil selected for this research represented three main classification groups, namely, low-organic, medium-organic and high-organic soil, in accordance with the standard criterion. Particle size distribution was determined using two types of laser diffractometers: the Helos laser diffractometer manufactured by Sympatec GmbH (Clausthal-Zellerfeld, Germany) and the laser particle size analyzer Analysette 22 MicroTech plus manufactured by Fritsch GmbH (Idar-Oberstein, Germany). The standard mechanical and sedimentation methods, which are perfect for testing mineral soils, are not applicable to organic soils; therefore, a serious problem was found and examined. A reference method that could verify the test results obtained using the laser diffractometer methods was required. After analyzing the literature, the hydrometric (sedimentation) method was adopted as the reference method. Currently, there are no reliable and fully verified methods for testing soils with such a complex skeleton structure, and the resources, standards and guidelines concerning the issues discussed are extremely limited; therefore, new research methods are being sought to fill this gap, and this work is a step in this direction. The results of the conducted studies and analyses have shown that laser diffractometry methods can be useful for determining the particle size distribution of organic soils, but to a limited extent, depending mainly on the quantity of organic substances. The highest agreement was obtained by comparing the results of the sedimentation method with those obtained using the diffractometer analyzer Analysette 22 in the group of highly organic soils. [ABSTRACT FROM AUTHOR]

This study proposes a new method to determine the particle size distribution (PSD) of soils by considering the electrical conductivity (EC) technique. A new EC probe was designed with a transparent thermoplastic, commonly known as acrylic, and brass electrodes. At first, the EC of a soil–water homogeneous suspension was calculated at different densities to obtain a calibration curve of each tested soil sample. During the PSD analysis, as the particles started to settle down in the basement due to gravity, the EC was measured at different time intervals, and the corresponding EC values were then matched with the calibrated EC values at different densities. The proposed method considered the conventional Stokes' law to determine the diameter of soil particles and the general percentage of passing mathematical expression to obtain the final PSD curve of each soil. The PSD analysis by the EC approach was later validated with that of hydrometer and laser diffraction methods, and in general, good agreements were obtained for identical soil samples at different classifications of soil particles such as clay, silt, and sand. Finally, reproducibility tests were also conducted and the new EC probe overperformed the hydrometer method in terms of both accuracy and precision. The finding from this study aimed to propose an alternative to determine the PSD of soils by using the EC technique with a high level of accuracy and efficiency. [ABSTRACT FROM AUTHOR]

There are various types of atomization measurements, mainly for liquids, and it is no exaggeration to say that it is the history of particle size measurement. When measuring the diameter of atomized droplets, it has long been a question of whether the measuring instruments are really showing the correct values. The Phase Doppler Interferometer (PDI), which appeared in this history, can simultaneously measure the particle size and flow velocity of droplets, and can also display the density and flux per unit volume (cc/cm2/s). When the measurement target is a spray, this means that larger particles have faster velocity and smaller particles have the opposite. In this article, I will look back on the history of measuring instruments related to atomization over the past 40 years, from the late 1980s when I first became involved in the world of atomization to the present day, focusing on the Phase Doppler Particle Analyzer. [ABSTRACT FROM AUTHOR]

The disaggregated inorganic grain size (DIGS) of bottom sediment analyzed with a Coulter Counter (CC) has been used to show that the fraction of sediment deposited in flocs (floc fraction) increased in both the near and far field after the introduction of open cage salmon aquaculture, altering benthic habitat and species composition. As a result, DIGS was identified as a potential indicator of regional environmental changes due to aquaculture. Laser diffraction is an attractive alternative to the CC because of its greater efficiency and larger size range. To determine if a laser diffraction instrument, Beckman-Coulter LS 13 320 (LS), could replace the CC within a Canadian national aquaculture monitoring program, the DIGS of 581 samples from five different regions in eastern Canada were analyzed with an LS and a CC. Results show that the LS could not be used to calculate floc fraction. Instead, % sortable silt and the volume % of inorganic particles < 16 µm were evaluated as alternative proxies for fine sediment properties. LS and CC values for these parameters were correlated, but they were significantly different and the relationship between the instruments was dependent on the area sampled. The LS did not capture variations between areas seen in the CC DIGS data. Where the DIGS from the CC found no sorting in the finest size classes, all the LS samples had similar size distributions characterized by smooth modal peaks. The LS and CC both return values that can be used to monitor changes in the deposition of fine-grained sediment, but the LS cannot determine changes in floc deposition and caution is required if comparing different sedimentary environments. [ABSTRACT FROM AUTHOR]

Comparative analysis of erythrocyte deformability in individuals with Diabetes Mellitus (DM) and healthy individuals (Control) was represented, focusing on the Elongation index (EI) calculation based on diffraction images. While no statistically significant differences in EI values were observed between the groups, we determined specific points along the deformability curve and revealed the first derivative of deformability curve (dEI / dSS) as a potential metric for quantifying erythrocyte response to deformation, where SS represents shear stress in Pa (Pascal). Statistically significant differences in dEI / dSS at the half maximum value of the deformability curve were identified, suggesting a slower erythrocyte response to shear stress in DM patients. Scatter plot analysis demonstrated a linear declining trend in dEI / dSS index with an increase in shear stress, indicating decaying erythrocyte responsiveness to higher shear stress values, particularly pronounced in DM patients. Although pilot, this study suggests that dEI / dSS can provide valuable insights into the hemorheological aspects of DM pathology and contribute to a comprehensive understanding of erythrocyte mechanobiological behavior in response to varying shear stress levels. Correlations between the proposed measure of RBC mechanical properties and established clinical markers of DM and its complications (serum cholesterol, creatinine, and urea level) are obtained to get preliminary insight into dEI / dSS application for better diagnosis and/or patient management. [ABSTRACT FROM AUTHOR]

Based on the results of an analysis of 174 samples of bottom sediments collected at 48 stations in the Chaun Bay during the cruise 60 of the R/V Akademik Oparin (October 2020), it was found that their grain size distribution varies from poorly sorted silty clay to well sorted sand. The results of the study led to conclusion that the main sedimentation mechanisms in Chaun Bay are thermal abrasion, river runoff, and abrasion, as well as ice rafting and aeolian transport. The zoning of grain size types of bottom sediments is related to the bottom topography and consistent with areas affected by riverine runoff, abrasion, and thermal coastal abrasion, as well as with the direction of currents. The high occurrence of coarse clastic matter in sediments is evidence of abrasion of the coastal zone and active ice rafting of large (up to 15 cm) rock fragments. The vertical variability of the grain size parameters of the studied bottom sediments within the upper 20 cm layer reflects gradual Late Holocene intensification of terrigenous (fluvial and thermal abrasion) fluxes with the current effects of climate change in the Arctic. [ABSTRACT FROM AUTHOR]

Dewatering of alkali metal halide salts in conventional co-current or counter-current spray driers to obtain low moisture content and agglomeration in resultant dried powders is difficult owing to their hygroscopic nature. Co-current spray driers offer the advantage of good heat transport characteristics in spray zone while counter-current spray driers offer better thermal utilization throughout the drying chamber. In the present work, modified prototype of a conventional counter-current spray drier is developed to obtain both these advantages in the drying chamber by employing induction heating and mechanical pulsation techniques. After carrying out several experiments in this prototype viz. Induction heating-based pulsed spray drier (IH-PSD), the optimal process parameters are obtained which maximize thermal utilization throughout the drying chamber and minimize both moisture content and agglomeration in resultant dried powders of sodium and potassium halide salts. The initial droplet and final particle size distributions are obtained using laser diffraction analyzer and sieve shaker experiments respectively. An experimentally validated numerical model implemented using open-source computational solvers is utilized to obtain average drying rates in IH-PSD. It is observed that the average drying rate lies between 0.03 and 0.18 mg/s and 0.04 and 0.14 mg/s for sodium and potassium metal halide salts respectively. Spray drying prototype coupled with Induction heating and mechanical pulsation. Dewatering of sodium and potassium metal halide salts using the spray drying prototype. Numerical-neural network model implemented by open source computational solvers. Utilization of Laser diffraction analyser for measurement of initial droplet size. Model calculates the average drying rate with an accuracy around 83%. [ABSTRACT FROM AUTHOR]

The authors study the effect the dispersion of particles of synthesized nickel–zinc ferrite powder has on its structural and magnetic properties. Ferrite powder is fabricated using ceramic technology. The average particle size is varied by means of mechanical activation. The patterns of the formation of nickel–zinc ferrite's properties are established via X-ray diffraction analysis, laser diffraction, and thermal analysis, depending on the modes of mechanical activation. [ABSTRACT FROM AUTHOR]

The influence of the degree of dispersion of a nickel–zinc ferrite powder of a Ni0.7Zn0.3Fe2O4 composition on its magnetic properties has been considered. The material has been synthesized using the ceramic technology with preliminary mechanical activation of precursors. The degree of dispersion has been varied using different modes of its dry grinding in a ball mill. The patterns of the changes in saturation magnetization and the coercive force as a function of grinding modes and a specific surface area of the ferrite powder have been established. The changes in the pattern of the magnetic phase transition in the region of the Curie temperature of materials with different degrees of dispersion have been determined. [ABSTRACT FROM AUTHOR]

Pathologies such as malaria, hemorrhagic stroke, sickle cell disease, and thalassemia are characterized by the release of hemoglobin degradation products from damaged RBCs. Hematin (liganded with OH−) and hemin (liganded with Cl−)—are the oxidized forms of heme with toxic properties due to their hydrophobicity and the presence of redox-active Fe3. In the present study, using the original LaSca-TM laser particle analyzer, flow cytometry, and confocal microscopy, we showed that both hematin and hemin induce dose-dependent RBC spherization and hemolysis with ghost formation. Hematin and hemin at nanomolar concentrations increased [Ca2+]i in RBC; however, spherization and hemolysis occurred in the presence and absence of calcium, indicating that both processes are independent of [Ca2+]i. Both compounds triggered acute phosphatidylserine exposure on the membrane surface, reversible after 60 min of incubation. A comparison of hematin and hemin effects on RBCs revealed that hematin is a more reactive toxic metabolite than hemin towards human RBCs. The toxic effects of heme derivatives were reduced and even reversed in the presence of albumin, indicating the presence in RBCs of the own recovery system against the toxic effects of heme derivatives. [ABSTRACT FROM AUTHOR]

In this study, dry dispersion laser diffraction was used to study the dispersibility of spheronized agglomerate formulations and identify geometric particle size metrics that correlated well with aerodynamic particle size distribution (APSD). Eleven unique batches of agglomerates were prepared for both laser diffraction and cascade impaction testing. Correlations between the particle size distribution (PSD) and aerodynamic particle size distribution (APSD) metrics for the eleven agglomerate batches were determined in a semi-empirical manner. The strongest correlation between APSD and PSD was observed between the impactor-sized mass (%ISM) and the cumulative PSD fraction <14.5 µm. The strongest correlation with fine particle fraction (FPF) was observed with the cumulative PSD fraction <0.99 micron (R-squared = 0.974). In contrast to the other APSD metrics, good correlations were not found between the mass median aerodynamic diameter (MMAD) and the cumulative PSD fractions. Overall, the implementation of laser diffraction as a surrogate for cascade impaction has the potential to streamline product development. Laser diffraction measurements offer savings in labor and turnaround time compared to cascade impaction. [ABSTRACT FROM AUTHOR]

Expanding emulsions with liquid CO2 facilitates the creation of aerosols with an average droplet diameter in the low micrometer size range, which is challenging with conventional atomizers. The droplet formation process of the expansion of high‐pressure emulsions was investigated using a plain‐orifice atomizer and different swirl nozzles. The local droplet size and droplet velocities were measured and used to estimate the local Weber number and thus infer the droplet size reduction. Measurements of the local mass concentration in the aerosol showed that, for the swirl nozzle, the highest concentration was found outside of the central axis, indicating radial momentum generated by the swirl nozzle. Furthermore, it was shown that the type of expansion nozzle used has an influence on the resulting median droplet size in the aerosol. For a water mass load of 0.01, the median droplet diameter was reduced from 8 to 3 μm by increasing the swirl number from 0.01 to 0.1. [ABSTRACT FROM AUTHOR]

Accurate particle size distribution (PSD) measurements of suspended particulate matter (SPM) composed of flocs and aggregates are important to improve understanding of ecological and geomorphological processes, and for environmental engineering applications. PSDs can be measured in situ (in the field) using a submersible sensor, or ex situ (in the laboratory) using samples. The methodological choice is often guided by logistical factors, and the differences in PSDs acquired by in situ and ex situ measurements is of concern. In this study, a laser‐diffraction instrument (the LISST‐200X) was used to compare in situ and ex situ PSD measurements. Samples measured ex situ were stored for three consecutive weeks and measured each week in a laboratory using different stirrer speeds. We observed that ex situ measurements display a higher D50 (median particle size) than in situ measurements of the same sample (up to 613% larger, 112% on average). Our experiments show that the difference between in situ and ex situ measurements can be explained by flocculation of the riverine sediments during the first week of storage. During the subsequent ex situ measurements, the stirring results in a significantly lower D50. Ex situ measurements are therefore unsuitable for flocculated SPM. This study provides recommendations for optimizing PSD measurements by calculating the measurement times required to obtain robust PSD measurements (exceeding 3 min per sample), which are larger for field samples with coarser particles and wider PSDs. Plain Language Summary: Measurements of the size of particles suspended in a water column are important for understanding many processes related to river ecology and morphology. It is possible to measure these particles directly in the field using a submersible sensor (in situ), or by taking samples and transporting them to a laboratory (ex situ). The choice between these options often depends on logistics, with little recognition of the impact that this choice can have on the measurements. In this research, the differences between in situ and ex situ measurements are explored. We find that ex situ measured particle sizes are on average 112% larger than in situ measurements, which can be related to flocculation of the riverine particles. Flocs are a combination of mineral particles (such as silt or clay) and organic particles, forming larger aggregates. Our results show that flocs grow when a sample is taken to the laboratory and stored. During ex situ measurements, which involve stirring, they break apart. Ex situ measurements are therefore unsuitable for determining the natural particle size. We show how long a measurement should last to give a representative particle size. In situ, longer measurement periods are needed. Key Points: The D50, a generic way to parametrize particle size distributions (PSDs), is not an absolute number, but depends on the measurement methodDifferences between in situ and ex situ measured PSDs are caused by the ex situ alteration of flocculated particlesA robust PSD measurement with laser diffraction takes longer for coarser field samples with a wider distribution [ABSTRACT FROM AUTHOR]

Although nasal inhalation products are becoming more and more important for the delivery of medicines, characterization of these products for quality control and assessment of bioequivalence is complicated. Most of the problems encountered are associated with the assessment of aerodynamic droplet/particle size distribution (APSD). The droplets produced by the various nasal devices are large, and for suspension products, individual droplets may contain multiple drug particles or none at all. Assessment of suspension products is further complicated by the presence of solid excipient particles. These complications make it imperative that the limitations of the instruments used for characterization as well as the underlying assumptions that govern the interpretation of data produced by these instruments are understood. In this paper, we describe various methodologies used to assess APSD for nasal inhalation products and discuss proper use, limitations, and new methodologies on the horizon. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate wNMR, an emerging noninvasive analytical technology, for characterizing aluminum-adjuvanted vaccine formulations. Methods: wNMR stands for water proton nuclear magnetic resonance. In this work, wNMR and optical techniques (laser diffraction and laser scattering) were used to characterize vaccine formulations containing different antigen loads adsorbed onto AlPO4 adjuvant microparticles, including the fully dispersed state and the sedimentation process. All wNMR measurements were done noninvasively on sealed vials containing the adsorbed vaccine suspensions, while the optical techniques require transferring the adsorbed vaccine suspensions out of the original vial into specialized cuvette/tube for analysis. For analyzing fully dispersed suspensions, optical techniques also require sample dilution. Results: wNMR outperformed laser diffraction in differentiating high- and low-dose formulations of the same vaccine, while wNMR and laser scattering achieved comparable results on vaccine sedimentation kinetics and the compactness of fully settled vaccines. Conclusion: wNMR could be used to analyze aluminum-adjuvanted formulations and to differentiate between formulations containing different antigen loads adsorbed onto aluminum adjuvant microparticles. The results demonstrate the capability of wNMR to characterize antigen-adjuvant complexes and to noninvasively inspect finished vaccine products. [ABSTRACT FROM AUTHOR]

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A diet containing powdered natural zeolite from the Mysovsky Mine (Khanty-Mansi Autonomous Okrug–Yugra) was tested for the effect on the erythrocyte capability of changing the shape in a shear flow in normal and hypothermic conditions in white outbred rats. Erythrocyte deformability was assessed by a laser diffraction technique implemented in a redesigned version of the ektacytomer. A comparison was performed with zeolite from the Kholinsky Mine (Zabaykalsky Krai), which is well studied and is widely used as a component of medicines and nutraceuticals. Hypothermia was shown to significantly increase erythrocyte deformability and lipid peroxidation (LPO) in test rats compared with control rats. The alterations were due to macrocytosis, which was demonstrated by flow cytometry. Natural zeolite powder used as a food additive exerted antioxidant and membrane-protecting effects in both of the rat groups. Erythrocyte deformability increased significantly, LPO decreased, and the Price–Jones curve expanded to the left as compared with observations in rats exposed to hypothermia, but not treated with zeolites. The results demonstrated that similar biological effects are exerted by natural clinoptilolite-containing zeolites from the two mines and that zeolites from the Mysovsky Mine can potentially be used as a raw material in drug production. [ABSTRACT FROM AUTHOR]

The phenomenon of diffraction of laser radiation by particles of a damaged surface layer of a piezoceramic deposited on a plane-parallel glass plate was studied. A diffraction pattern is clearly observed in reflected and transmitted light, which is an alternation of light and dark concentric rings. These rings correspond to the conditions of diffraction maxima and minima. A bright spot is observed in the center of the diffraction pattern. The dependence of the radius of diffraction rings on the thickness of the glass plate was established. The diffraction angles at a given value of the order of maximum for different thicknesses of the glass plate were the same. The particles of the damaged surface layer of the piezoceramic, which scatter light, have different characteristic sizes. The study of particles using optical microscopy showed that their sizes are in the range of ~ (1 ÷ 3) μm. The shape of the grains is predominantly close to spherical. The Fraunhofer approximation was used to analyze the diffraction pattern. The distribution of the light intensity of the diffraction pattern depending on the diffraction angle has been analyzed. The simulation of the total scattered intensity as a function of the angle for particles with a diameter of 1.7 μm and 3.0 μm has been performed. The diffraction angles become smaller as the particle size increases. The distribution of the light flux in the diffraction pattern is constructed. This graph shows that most of the scattering intensity is concentrated near the center of the diffraction pattern, where the vast majority of the laser radiation falls. As the diffraction angle increases, the relative intensity of the maxima obeys the regularity 1 : 0.71 : 0.25 : 0.13. The size of the particles of the damaged surface layer of the piezoceramic was estimated using the laser diffraction method. The average particle diameter of the surface damaged layer of the piezoceramic is 1.7 μm. It can be argued that particles of such sizes make the main contribution to the creation of the diffraction pattern obtained by us under these experimental conditions. [ABSTRACT FROM AUTHOR]

This article presents research results on mechanically generated oil mists. The research was carried out for oil mixtures for the Agip/Eni Cladium 120 SAE 40 API CF oil for industrial and marine engines diluted with diesel oil Orlen Efecta Diesel Bio at diesel oil concentrations of 2%, 5%, 10%, 20%, and 50% m/m. Pure lubricating oil and pure diesel oil were also tested. Droplet size distributions were determined for the reference moment at which residual discrepancies R between the measurement data and the sprayed pure diesel oil calculation model obtained the lowest value. For mechanically generated oil mists, the light transmission coefficient through the oil mist T, the specific surface area of the oil mist SSA, and the volumetric share of drops DV(V%) for 10%, 50%, and 90% of the total volume of the generated oil mist were determined. The span of the volumetric distributions of droplet sizes SPAN, Sauter mean diameter D[3,2], De Brouckere mean diameter D[4,3], the volumetric and mass percentage of droplets with diameters ≤5 μm (diameters necessary for a crankcase explosion), the minimum difference between the measurement results, and the calculation model used by the residual error measuring device were determined. The best fit in each measurement cycle (the smallest R value was analyzed. For specific indicators, correlations with diesel oil levels in the mixture were determined using the Pearson rXY linear correlation coefficient. Those results confirmed an increase in smaller-diameter droplets, an increase in the number of droplets with diameters up to 5 μm, and an increase in the span of the oil mist droplet diameter distribution with additional diesel oil. This confirmed a relationship between an increased lubricating oil dilution and an increased explosion risk in the crankcase. [ABSTRACT FROM AUTHOR]

Significant research has focused on North American dirt and synthetic Thoroughbred racing surfaces. Turfgrass racing surfaces have received less consideration. Basic information, including climate and turfgrass species, can be documented relatively easily. However, a key characteristic, the particle size distribution of the growing medium, is not readily available for turf tracks. Particle size distribution and the deviation from nominal values are important to infiltration rate, shear strength, and turf health, as well as being critical for the selection of top-dressing and divot repair sand. The primary difficulty with obtaining the particle size distribution is the relatively large quantity of material required for traditional sedimentation test methods. Sampling an active racing surface could present a risk to the horses and riders. Laser diffraction testing methods present an opportunity to use much smaller samples. The use of smaller samples introduces new questions about the ability of a small sample to represent a large area, such as a racetrack. Tests were carried out with high resolution sampling at one racetrack. By sampling a large number of locations, 96 locations on a single racetrack, the variability of the track could be evaluated, and an eight-sample protocol was developed. Using the eight-location protocol, 22 additional turf racetracks throughout North America were sampled. A total of 23 turf racetracks were tested, representing all three of the designs used for North American turf racetracks. By looking at the three different track designs: engineered profile, engineered profile with fiber, and native soil, appropriate testing parameters and measurements were identified. While the primary objective was to understand turf racetracks, this unique data set also provided a method to investigate the applicability of laser diffraction for the analysis of soil samples. Mineralogy and organic content had previously been identified as important in the measurement of particle size distribution using laser diffraction. Mineralogy and organic content were determined for samples from each surface using X-ray diffraction (XRD) and loss on ignition. The PSD of the three types of turfgrass horse racing surfaces showed significant differences between native soil (N), engineered surfaces without synthetic fibers (EWOF), and engineered surfaces with synthetic fibers (EWF). These basic design descriptions were also found to be sufficient for making reasonable estimates of the settings used in the machine configuration and sample preparation. A single refractive index was used for the entire range of samples in this group; however, the sample quantity tested was different for the three different types of track designs. [ABSTRACT FROM AUTHOR]

Purpose: The laser diffraction method has become increasingly popular during the last decades to measure the grain size distribution of various environmental particles originating from sediments, soils or river suspended sediments. However, the measurement of multimodal samples containing sands is still an issue. The aim of this study is to discuss the limits of the laser diffraction method in measuring the sand fraction of bimodal samples. Materials and methods: A systematic comparison of four commercially available laser diffraction instruments (Cilas 1190L, Fritsch Analysette 22 Nanotec, Malvern Mastersizer 3000, and Sequoia Lisst 200X) is performed on 12 unimodal and bimodal samples of glass beads and silica-rich natural sands. Results: Measured grain size distributions differ between the four instruments. Most important differences occur in bimodal samples containing a sand fraction, where some instruments have major difficulties to estimate the proportion of the fine towards coarse mode correctly, with errors up to 100%. Conclusion: In accordance with the observation of coarse particles accumulating in low-velocity areas within the sampling tank, the creation of an imperfect suspension within the sampling tank is considered as a main reason for the differences. The choice of the most suitable measurement parameters is crucial to obtain accurate and precise measurements. However, these parameters cannot be compared between the instruments, nor exist precise user guidelines. Therefore, testing several measurement parameters before analyzing novel sample compositions using laser diffraction is recommended. [ABSTRACT FROM AUTHOR]

Plant protection control based on the spray application of plant protection products is a very complex task depending on a series of factors, among which droplet size is the most influential for deposition and pesticide effectiveness. In fact, the adoption of the correct droplet size can ensure that the required dose reaches the target area and is not wasted, minimizes the off-target losses due to evaporation, drift and run-off and, at the same time, enhances the operator's safety in terms of inhalation, ingestion and dermal exposure. In this paper, after defining some mean characteristic diameters helpful for a description of a drop population and focusing on the main drop size distribution functions for the statistical characterization of sprays, a critical analysis of known methods, both intrusive and non-intrusive, for drop size measurement is carried out by reviewing the literature. Among intrusive methods, the liquid immersion method and the use of water-sensitive papers are discussed, whereas, among non-intrusive methods, laser-based systems (laser diffraction, phase Doppler particle analysis) and high-speed imaging (shadowgrapy) are presented. Both types of method, intrusive and non-intrusive, can be used in machine-learning-based approaches exploiting regression techniques and neural network analysis. [ABSTRACT FROM AUTHOR]

Simple Summary: An important issue in cancer chemotherapy is minimizing its side effects. The extreme toxicity of chemotherapy drugs is due to their task of preventing the multiplication of cancer cells and causing cancer cell death. One of their most common undesirable side effects is anemia, which is caused by a decrease in the number of red blood cells (RBCs) circulating in blood, which in turn results in a lack of oxygen in tissues. The manifestation of anemia is associated not only with the inhibition of the hematopoietic function of bone marrow but also with direct damage to RBCs during the drugs' infusion and circulation. Here, we investigated how frequently used chemotherapy drugs directly affect RBCs. Our results show that chemotherapeutic drugs, whose main task is to damage the DNA of cancer cells and prevent their division, have a noticeable toxic effect on RBCs. However, this effect is lower than the effect caused by drugs, which disrupt the dynamics of the cytoskeleton during cell division. Direct simulation of RBCs' transport in microchannels of a microfluidic device was allowed to integrally assess the cells' functionality and the capability of passing through microcapillaries where gas transport mainly occurs. We demonstrate that after exposure to drugs, regardless of their type, the number of damaged cells did not exceed 10%, which indicates the balance of the drugs' therapeutic doses. Our data along with the developed research method could be used to work out an effective combination of chemotherapeutic drugs as well as to calculate the efficient therapeutic drug doses for cancer treatment to reduce anemia side effects. Red blood cells (RBCs) are the most numerous cells in the body and perform gas exchange between all tissues. During the infusion of cancer chemotherapeutic (CT) agents, blood cells are the first ones to encounter aggressive cytostatics. Erythrocyte dysfunction caused by direct cytotoxic damage might be a part of the problem of chemotherapy-induced anemia—one of the most frequent side effects. The aim of the current study is to evaluate the functional status of RBCs exposed to mono and combinations of widely used commercial pharmaceutical CT drugs with different action mechanisms: paclitaxel, carboplatin, cyclophosphamide, and doxorubicin, in vitro. Using laser diffraction, flow cytometry, and confocal microscopy, we show that paclitaxel, having a directed effect on cytoskeleton proteins, by itself and in combination with carboplatin, caused the most marked abnormalities—loss of control of volume regulation, resistance to osmotic load, and stomatocytosis. Direct simulations of RBCs' microcirculation in microfluidic channels showed both the appearance of a subpopulation of cells with impaired velocity (slow damaged cells) and an increased number of cases of occlusions. In contrast to paclitaxel, such drugs as carboplatin, cyclophosphamide, and doxorubicin, whose main target in cancer cells is DNA, showed significantly less cytotoxicity to erythrocytes in short-term exposure. However, the combination of drugs had an additive effect. While the obtained results should be confirmed in in vivo models, one can envisioned that such data could be used for minimizing anemia side effects during cancer chemotherapy. [ABSTRACT FROM AUTHOR]

This study evaluates the laser in situ scattering and transmissometry (LISST) instrument LISST-SL2, a laser diffraction instrument for suspended sediment sampling in rivers, with concurrent physical measurements of suspended sediment concentration (SSC) and particle size distribution (PSD) as well as velocity measurements by an acoustic Doppler current profiler (ADCP). We collected 136 LISST-SL2 samples along with 61 physical samples for SSC measurement, of which 24 physical samples included PSD measurement during 2018–2020 from 11 sites in Washington state and Virginia. An effective density is required to convert the measured volumetric SSC by the LISST-SL2 into a reported mass SSC, and by default the LISST-SL2 assumes a value of 2.65 g/mL. From our data set, we computed effective densities (mass SSC/volumetric SSC) that ranged from 0.5 to 5.4 g/mL , with a best-fit value of 2.05 g/mL. Additionally, the LISST-SL2 was not able to measure the finest sediment sizes in suspension, which affects the resulting PSD. Therefore, we propose some adjustments of the LISST-SL2 data with a supporting physical sample to account for these effective density and PSD issues. When doing so, we were able to reduce the root-mean square relative error (RMSRE) to 18% from 117% for SSC, and to 26% from 78% for PSD. LISST-SL2 velocities were generally higher than ADCP velocities with a 21% RMSRE. Our results and guidance will allow for more accurate sampling by the LISST-SL2, which has potential for studying spatial and temporal variation of suspended sediment characteristics in rivers. [ABSTRACT FROM AUTHOR]

Wastewater treatment generates large amounts of sludge, requiring the implementation of techniques reducing the volume of excess sludge and its impact on the environment. Disintegration of the excess sludge is a pre-treatment process aimed at improving the anaerobic digestion of the sludge. Its main objective is the dispersion of sludge flocks and the lysis of microbial cells. Ultrasonic (US) preconditioning is one of the most widespread mechanical disintegration methods, and mechanical mixing of the sludge before ultrasonic treatment can effectively enhance the US effects. We examined the connection of the particle size of sludge (after homogenization) and the release of the intracellular material, monitored as cell lysis indicator kdSCOD, after the application of ultrasound. Pre-homogenization of the excess sludge (at three different mixing times, 60, 120, and 180 s) was used to mix the sludge thoroughly and reduce the particle size of the sludge before ultrasonic treatment. Particle size measurement via light scattering allows for the precise determination of particle size distribution. Homogenization (pre-dispersion) before US at EV 5.7 Wh·L–1 led to an increase in the kdFCOD dispersion indicators from 1.89 (without mixing) to 3.33, 3.75, and 4.08 for three mentioned above mixing times, respectively, and an increase in the cell lysis indicator kdSCOD from 1.33 to 1.65, 1.85, and 1.96, respectively. Our results confirm the connection between the size of the sludge flocs before US conditioning and the disintegration effects as well as the increase in the energy efficiency of the US disintegration. [ABSTRACT FROM AUTHOR]

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

Fourier transform infrared (FTIR) spectroscopy and laser diffraction are commonly applied methods to assess the quality of activated and digested sludge. However, the effect of particle size on FTIR data has never been thoroughly explored. There is also scarce literature on the application of FTIR spectroscopy in conjunction with laser diffraction to investigate changes in the composition and structure of the raw, untreated activated and sewage sludge. In this paper, laser diffraction and FTIR analyses were applied to evaluate the composition, structure and properties of particles in suspensions of activated, thickened and digested sludge samples collected at Janówek Wastewater Treatment Plant (WWTP) located in Wrocław, Poland. FTIR analyses led to the identification of characteristic compounds in the aforementioned types of sludge and processes which they had undergone, for example, decarboxylation and deamination. Laser diffraction tracked the changes in the size and structure of particles in the suspension. Thickened sludge suspensions, which had the largest active surface and the lowest compactness, were characterized by the highest sorption capacity and catalytic activity. The conducted research has shown that the intensity of infrared (IR) absorption is size dependent – smaller particles in the suspension had a higher absorbance intensity in a given wavenumber ranges than larger ones. [ABSTRACT FROM AUTHOR]

Hypo- and hyperthermia affect both primary and secondary hemostasis; however, there are controversial data concerning platelet activation and the underlying mechanisms under hypo- and hyperthermia. The discrepancies in the data could be partly explained by different approaches to hemostatic reactions analysis. We applied a new LaSca-TMF laser particle analyzer for a simultaneous fluorescence and laser scattering analysis of platelet responses at different temperatures. Human platelets were activated by ADP in a wide range of temperatures, and platelet transformations (e.g., a shape change reaction, aggregation and clot formation) and the intracellular calcium concentration ([Ca2+]i) were analyzed by LaSca-TMF and confocal microscopy. The platelet shape change reaction gradually increased with a rising temperature. The platelet aggregation strongly decreased at low ADP concentrations with the augmentation of the temperature and was independent of the temperature at high ADP concentrations. In contrast, the clotting time decreased with a temperature increase. Similar to the aggregation response, a rise in [Ca2+]i triggered by low ADP concentrations was higher under hypothermic conditions and the differences were independent of the temperature at high ADP concentrations. We showed that the key reactions of cellular hemostasis are differentially regulated by temperature and demonstrated for the first time that an accelerated aggregation under hypothermic conditions directly correlated with an increased level in [Ca2+]i in platelets. [ABSTRACT FROM AUTHOR]

BACKGROUND: Nanoemulsions formulated with citric essential oils are currently of interest because of their physical and chemical properties and multiple applications in areas such as the food industry or agrochemicals. These are thermodynamically unstable and have almost Newtonian flow behaviour, but a suitable formulation allows systems to be obtained with good physical stability and rheological properties. The addition of pectin makes this possible. In this work, food nanoemulsions formulated with pectin, orange essential oil (5 wt%), and Tween 80 were obtained by microfluidization. First, the effect of Tween 80 concentration from 1 to 5 wt% on emulsions without pectin was evaluated. Then, pectin was added to the most stable nanoemulsion obtained and two variables were studied: the pectin solution concentration (from 2 to 6 wt%) and the pectin/emulsion ratio (1:1 or 2:1) at a fixed pectin concentration. RESULTS: Rheological, laser diffraction, and multiple light scattering techniques were employed to determine the content of Tween 80 that results in the most stable nanoemulsion without pectin, which was 3 wt%. In addition, these techniques were used to determine the structure and physical stability of the nanoemulsions containing orange essential oil and pectin. The results obtained showed that the emulsions containing 2 wt% pectin were destabilized before 24 h. Furthermore, the emulsion with 6 wt% pectin and a 2:1 pectin/emulsion ratio showed the highest viscosity and the lowest mean diameters, and therefore the greatest stability. CONCLUSION: This work extends the knowledge of formulation of nanoemulsions and using essential oils. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Purpose: In continuous manufacturing of pharmaceuticals, dry granulation is of interest because of its large throughput capacity and energy efficiency. In order to manufacture solid oral dosage forms continuously, valid control strategies for critical quality attributes should be established. To this date, there are no published control strategies for granule size distribution in continuous dry granulation. Methods: In-line laser diffraction was used to determine the size of granules in a continuous roll compaction/dry granulation line (QbCon® dry). Different process parameters were evaluated regarding their influences on granule size. The identified critical process parameters were then incorporated into control strategies. The uncontrolled and the controlled processes were compared based on the resulting granule size. In both processes, a process parameter was changed to induce a shift in median particle size and the controller had to counteract this shift. Results: In principle, all process parameters that affect the median particle size could also be used to control the particle size in a dry granulation process. The sieve impeller speed was found to be well suited to control the median particle size as it reacts fast and can be controlled independently of the throughput or material. Conclusion: The median particle size in continuous roll compaction can be controlled by adjusting process parameters depending on real-time granule size measurements. The method has to be validated and explored further to identify critical requirements to the material and environmental conditions. [ABSTRACT FROM AUTHOR]

The size distribution of droplets in emulsions is very important for adjusting the effects of many indices on their quality. In addition to other methods for the determination of the size distribution of droplets, the usage of machine learning during microscopic analyses can enhance the reliability of the measurements and decrease the measurement cost at the same time. Considering its role in emulsion characteristics, in this study, the droplet size distributions of emulsions prepared with different oil/water phase ratios and homogenization times were measured with both a microscopy-assisted digital image analysis technique and a well-known laser diffraction method. The relationships between the droplet size and the physical properties of emulsions (turbidity and viscosity) were also investigated. The results showed that microscopic measurements yielded slightly higher values for the D(90), D[3,2], and D[4,3] of emulsions compared to the laser diffraction method for all oil/water phase ratios. When using this method, the droplet size had a meaningful correlation with the turbidity and viscosity values of emulsions at different oil/water phase ratios. From this point of view, the usage of the optical microscopy method with machine learning can be useful for the determination of the size distribution in emulsions. [ABSTRACT FROM AUTHOR]

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

One of the main problems in the production of tablets, which has significant negative consequences, is the segregation of the tablet mixture leading to inhomogeneity of dosage units, material losses in the manufacturing process and improperness of the specified pharmaceutical technical characteristics of the mixture. The aim of the research. This work aims at the pharmaceutical technical study of the substances N-acetyl-D-glucosamine and Actimask® Acetaminophen and determination the uniformity of the powder mixture of active pharmaceutical ingredients (APIs) to predict the optimal technology for obtaining a pharmaceutical formulation with the acceptable properties. Materials and methods. N-acetyl-D-glucosamine (Zhejiang Candorly Pharmaceutical, China) and Actimask® Acetaminophen (SpiPharma, USA) were used. Scanning probe microscope Solver P47N-PRO («NT-MDT», Russia), optical microscope, flowability tester VP-12A, laser diffraction particle size analyzer SALD-2201 («Shimadzu», Japan), liquid chromatograph Agilent 1260 Infinity II with Diode Array Detector (Agilent Technologies, USA), spectrophotometers Shimadzu UV-1800 («Shimadzu», Japan) were used. The study of API pharmaceutical technical properties (microscopic characteristics, moisture absorption capacity, flowability, bulk volume and tapped volume, particle size distribution by sieve analysis and laser diffraction), as well as vibration simulation and following chromatographic study were carried out in this work. Results and discussion. The shape of the particles N-acetyl-D-glucosamine and Actimask® Acetaminophen, which was determined by microscopic analysis, demonstrated the possibility of N-acetyl-D-glucosamine particles to stick to Actimask® Acetaminophen ones. The experimental study allowed to reveal the hygroscopicity of both APIs; poor flowability, unsatisfactory Hausner ratio, and Carr index for N-acetyl-D-glucosamine; excellent flowability, Hausner ratio, and Carr index for Actimask®. Vibration caused segregation of the powder mixture. It was found that all layers do not meet the requirements and an excessive content of Actimask® is registered, which indicates the stratification of the powder mixture. Conclusions. The physical properties of the substances were determined and found to have significant differences in their particle size distribution. Segregation of the mixture after vibration was confirmed by laser diffraction and assay analysis. In order to solve the segregation problem, the granulation of N-acetyl-D-glucosamine may be proposed. [ABSTRACT FROM AUTHOR]

Major modifications are made to the setup and signal processing of the method of in-situ measurement of the pitch of a diffraction grating based on the angles of diffraction of the diffracted optical frequency comb laser emanated from the grating. In the method, the improvement of the uncertainty of in-situ pitch measurement can be expected since every mode in the diffracted optical frequency comb laser can be utilized. Instead of employing a Fabry-Pérot etalon for the separation of the neighboring modes in the group of the diffracted laser beams, the weight-of-mass method is introduced in the method to detect the light wavelength in the Littrow configuration. An attempt is also made to reduce the influence of the non-uniform spectrum of the optical comb laser employed in the setup through normalization operation. In addition, an optical alignment technique with the employment of a retroreflector is introduced for the precise alignment of optical components in the setup. Furthermore, a mathematical model of the pitch measurement by the proposed method is established, and theoretical analysis on the uncertainty of pitch measurement is carried out based on the guide to the expression of uncertainty in measurement (GUM). [ABSTRACT FROM AUTHOR]

Purpose: Roll compaction/dry granulation is established in manufacturing of solid oral dosage forms and, within the context of continuous manufacturing, it has sparked interest as material is fed, processed, and ejected continuously while also providing large possible throughputs. However, this amount of material has to be adequately controlled in real time to assure quality. Methods: This research aimed at monitoring the critical quality attribute granule size distribution in continuous roll compaction/dry granulation (QbCon®; L.B. Bohle, Ennigerloh, Germany) using in-line and on-line laser diffraction. The influence of varying process parameters and excipient formulations was studied and evaluated with the prospect of using this technique to develop control loops. For this purpose, residence time parameters were assessed. In- and on-line data was compared with off-line laser diffraction and dynamic image analysis data. Results: The system successfully monitored the granule size distribution in a variety of process parameters and throughputs (up to 27.5 kg/h). It was sensitive to changes in process parameters and changes in material blends, which could pose a potential threat to the final drug products' quality. Average event propagation time from the compaction zone to the laser diffraction system of 17.7 s demonstrates the systems' fast reaction time. Conclusion: Results highlight laser diffraction as a valuable method of in- and on-line size determination and allow for the development of a control strategy using this principle. [ABSTRACT FROM AUTHOR]

The volume fraction of the dispersed phase in concentrated soft (dairy) microgels, such as fresh cheese, is directly related to structure and rheology. Measurement or modeling of volume fraction for soft and mechanically sensitive microgel dispersions is problematic, since responsiveness and rheological changes upon mechanical input for these systems limits application of typical functional relationships, i.e., using apparent viscosity. In this paper, we propose a method to measure volume fraction for soft (dairy) microgel dispersions by standard addition and volume-weighted particle size distributions obtained by static light scattering. Relative particle volumes are converted to soft particle volume fraction, based on spiked standard particle volumes. Volume fractions for two example microgel dispersions, namely, differently produced fresh cheeses, were evaluated before and after post-treatments of tempering and mechanical processing. By selecting the size of standard particles based on size ratios and the levels of the mixing ratios/relative fractions, the method could be applied robustly within a wide range of particle sizes (1 to 500 μm) and multimodal size distributions (up to quadmodal). Tempering increased the volume fraction for both example microgel dispersions (P < 0.05). Subsequent mechanical treatment reduced the volume fraction back to the starting value before tempering (P < 0.05). Furthermore, it was shown that the increase and successive decrease in apparent viscosity with tempering and mechanical post-treatments is not exclusively due to particle aggregation and breakdown, but to volume changes of each particle. For environmentally responsive soft matter, the proposed method is promising for measurement of volume fraction. [ABSTRACT FROM AUTHOR]

In this study, the particle size distribution (PSD) of the soil sediment from topsoil obtained from soil erosion experiments under different conditions was measured. Rainfall simulators were used for rain generation on the soil erosion plots with slopes 22°, 30°, 34° and length 4.25 m. The influence of the external factors (slope and initial state) on the particle and aggregate size distribution were evaluated by laser diffractometer (LD). The aggregate representation percentage in the eroded sediment was also investigated. It has been found that when the erosion processes are intensive (steep slope or long duration of the raining), the eroded sediment contains coarser particles and lower amounts of aggregates. Three methods for the soil particle analyses were tested: (i) conventional–sieving and hydrometer method; (ii) PARIO Soil Particle Analyzer combined with sieving; and (iii) laser diffraction (LD) using Mastersizer 3000. These methods were evaluated in terms of reproducibility of the results, time demands, and usability. It was verified that the LD has significant advantages compared to other two methods, especially the short measurement time for one sample (only 15 min per sample for LD) and the possibility to destroy soil aggregates using ultrasound which is much easier than using hexametaphosphate. [ABSTRACT FROM AUTHOR]

The article aims to present a comparative study of two methods used to determine the particle size distribution of fine and medium coarse soils. These methods are used to determine the grain size distribution curve in practice; however, for different purposes. The classical sedimentation method, based on the Stoke's sedimentation law (hydrometer, areometric, the Casagrande's method), standardized for a geotechnical classification of soils was compared with the laser diffraction method on the Mastersizer 3,000 analyser used for soil science purposes. The first comparison on nine samples showed significant differences, especially for larger fractions above 0.01 mm. All measured values of falls from laser diffraction analysis (LDA) showed higher values of all analysed fractions. It was also interesting to follow the trend between the tests for the preparation of conversion factors. The analysis also outlined the direction for further comparison. For the geotechnical use of the LDA, it will be necessary to take into account the sample preparation and processing before analysis. [ABSTRACT FROM AUTHOR]

"Surgical smoke" is an airborne by-product of electrosurgery comprised of vapour and suspended particles. Although concerns exist that exposure may be harmful, there is a poor understanding of the smoke in terms of particle size, morphology, composition and biological viability. Notably, it is not known how the biological tissue source and cutting method influence the smoke. The objective of this study was to develop a collection method for airborne by-product from surgical cutting. This would enable comprehensive analyses of the particulate burden, composition and biological viability. The method was applied to compare the electrosurgical smoke generated (in the absence of any evacuation mechanism) with the aerosolized/airborne by-products generated by ultrasonic and high-speed cutting, from bone and liver tissue cutting. We report a wide range of particle sizes (0.93–806.31 μm for bone, 0.05–1040.43 μm for liver) with 50% of the particles being <2.72 μm (~PM2.5) and 90% being <10 μm (PM10). EDX and biochemical analysis reveal components of biological cells and cellular metabolic activity in particulate from liver tissue cut by electrosurgery and ultrasonic cutting. We show for the first time however that bone saws and ultrasonic cutting do not liberate viable cells from bone. [ABSTRACT FROM AUTHOR]

Bauxite residue, a typical industrial solid waste which contains a large amount of Na+, is usually physically degraded. Understandings of aggregate formation, which is a critical process in soil development, are essential to facilitate ecological rehabilitation on the disposal areas. However, few studies have investigated the aggregation behaviour and mechanisms of key salt ions (Ca2+ and Na+) in residue aggregates. Therefore, an integrated method of Le Bissonnais' method, the combined determination method and laser diffraction measurements was applied to evaluate aggregate stability, surface properties and disintegration behaviour of bauxite residue following Ca/Na additions. With increasing Ca2+ addition, mean weight diameter increased, indicating improved resistance to dispersion. Ca2+ had a positive effect on flocculation of silt‐size microaggregates, while disintegration was induced following Na+ addition. Repeated laser diffraction analysis of residue samples circulating in 50 mmol L−1 electrolyte solution (Ca2+/Na+) provided a detailed view of the changes in particle size distribution as aggregates fragmented. The visualized three‐dimensional surface map revealed that Na+ promoted the disintegration of >250 μm aggregates into finer dispersed particles, while Ca2+ protected the microaggregates from fragmenting into smaller particles. Variation in electrochemical properties of aggregate surfaces affected the micro‐morphology significantly. The findings provide a new approach to specify pedogenic aggregate behavior of bauxite residue, while revealing the effects of Ca2+/Na+ on aggregate stability, surface electrochemical properties and its micromorphology. The results will provide a detailed understanding of aggregate behavior during soil formation process in bauxite residue. [ABSTRACT FROM AUTHOR]

The dispersity of an emulsion of treated mineral oil used as a coal-flotation reagent is studied by laser diffraction. A finely disperse oil emulsion in water is produced by selecting optimal duration and intensity of dispersion. Ozonization is used to improve the reagent's flotational activity. The influence of ozonization on the size distribution of the oil droplets in emulsification is assessed. [ABSTRACT FROM AUTHOR]

A combination of laser diffraction and wet sieving through a nylon screen with a 0.1-mm mesh has been suggested for the particle-size analysis of silty bottom sediments from estuarine and coastal sea areas. The necessity of individual determination of sand fractions even in case of the technical ability of the device to analyze the content of coarse particles to 2 mm in size is shown. This is related to poor sorting of coastal silts and inadequately represented weighed samples used for the standard laser diffraction particle-size analysis. In addition to sand fractions, the pre-sieving affects the determination of the 0.1–0.01 mm silt fractions, while its impact on the analysis of pelite fractions of less than 0.01 mm is minimal. The effectiveness of the proposed modified method is proved by the closer correlation between the content of pelite fractions and the concentration of metals and organic carbon in bottom sediments. [ABSTRACT FROM AUTHOR]