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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]

The article presents the research results of fume morphology derived from arc welding of stainless steels of 1.4301 and 1.4828 grade. The analysis was performed using laser diffraction and high-resolution scanning electron microscopy. Welding fume has been classified by the International Agency for Research on Cancer (IARC) as a group of agents with proven carcinogenic effects to human. The assessment of the risk related to exposure to welding fume emission depends on the amount of fume generated, its chemical composition and morphology. The combined analysis of these factors determines the toxicity of fume and its impact on the human body. The results of the fume particle size distribution and the analysis of the shape and chemical composition using SEM with EDS in connection with the determination of the fume emission rate enable to obtain an overall assessment of the health risk as-sociated with welding fume. Such assessment is particularly important during welding processes of corrosion-resistant steels, due to the presence of chromium and nickel compounds in the fume, which are classified as substances with proven carcinogenic effects to human (Group 1 according to IARC guidelines). It was found that 15-17% of particles deriving from arc welding belong to the respirable and tracheal fractions, which are the most harmful due to the penetration beyond the larynx.

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]

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]

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]

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]

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.

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]

Population balance modelling is a widely used tool to understand the mechanism and kinetic parameters of crystal growth at the bench, to facilitate scale-up to Production. In this work, we present recommendations for particle size and shape analytical methods to improve the predictive capability of 1D and 2D population balance models for crystallisation of contemporary active ingredients. For 1D models, we report that the optical model for laser diffraction, a common technique for measuring particle size distribution, can significantly impact the growth parameters resolved from the model. For 2D models, particle image analysis of powders and single crystals give valuable length and width data to predict how the aspect ratio of particles evolves. Future work will be directed towards applying these tools when scaling a crystallization process.

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]

Dry powder inhalers, comprising an active pharmaceutical ingredient (API) and carrier excipients, are often used in the delivery of pulmonary drugs. The stability of the API particle size within a formulation blend is a critical attribute for aerodynamic performance but can be challenging to measure. The presence of excipients, typically at concentrations much higher than API, makes measurement by laser diffraction very difficult. This work introduces a novel laser diffraction approach that takes advantage of solubility differences between the API and excipients. The method allows insight into the understanding of drug loading effects on API particle stability of the drug product. Lower drug load formulations show better particle size stability compared with high drug load formulations, likely due to reduced cohesive interactions. [ABSTRACT FROM AUTHOR]

The modern food industry requires new analytical methods for high-demand food supplements, personalized diets, or bioactive foods development. One of the main goals of the food industry is to discover new ways of food fortification. This applies to food products or supplements for human and animal diets. In our research, we focused on the solid particles of AproTHEM (dried porcine hemoglobin), which is approved for animal feeding and as a meat product additive, and AproFER 1000 (heme iron polypeptides), which is still being investigated. The study showed the possible application of advanced techniques for the examination of iron-based food additives. We evaluated selected techniques for particle size and morphology examination such as laser diffraction, optical microscopy, as well as scanning electron microscopy, and briefly discussed their usefulness compared with other techniques. On the basis of our results, we proposed a path of microscopic analysis for the study of material homogeneity. The structure of heme iron was evaluated by X-ray diffraction, FT-IR, and Raman spectroscopy supported with thermal behavior analysis (differential scanning calorimeter). Furthermore, a portable colorimeter was applied for L*a*b* color analysis. Our study proved that for new food product development, particle size analysis as well as typically used advanced materials techniques can be successfully applied.

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]

This paper deals with the problem of determining the particle size distribution of selected organic soils from the vicinity of Rzeszów (Poland), using a laser diffractometer method, the knowledge of which will allow to determine the degree of differentiation or similarity of the tested organic soils in this aspect. The HELOS Laser Diffractometer manufactured by Sympatec GmbH was used for the tests. For proper analysis, the researches results in the form of graphs were grouped according to the content of organic substances in accordance with the standard classification. The conducted research was primarily aimed at presenting the grain differentiation and particle size distribution in terms of the applied method and comparing the test results of samples of selected, different organic soils, prepared using the same dispersion procedure and carried out in exactly the same test conditions, generated using capabilities of a diffractometer. Summing up, the laser diffractometer method presented in the article, although not fully verified in the case of organic soils, seems to be a the perspective method with capabilities allowing it to be nominated as an exceptionally useful method for the investigations of soft soils, including organic soils. [ABSTRACT FROM AUTHOR]

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]

Based on laser-diffraction technique, the maximum entropy technique is applied to measure particle number concentration and size distribution in pneumatic transport. The information of particle number concentration and size distribution can be obtained simultaneously without distort the fluid and the particle trajectories. Detailed information about the distribution of the particle size and concentration in gas-solid two-phase flows near sand-bed surface are obtained in a large-scale wind tunnel test system. The experimental result shows that particle number concentration increases linearly with the increase of the wind speed. The mean particle size decreases exponentially with height (H > 3 cm), but almost unchanged for H

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]

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]

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]

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]

[Display omitted] • We introduce a new method to characterize milk fat globule (MFG) size distributions. • The method (3D confocal microscopy, CLSM) is accurate for MFGs from 0.5–10 μm. • In contrast to laser diffraction, CLSM retrieves no bimodal MFG size distribution. • Laser diffraction results for human milk should be interpreted with care. Milk fat globules (MFGs) in human milk provide energy to breastfed infants and support infant development. Accurate measurements of MFG size distributions are important to better understand MFG function and origin, as well as the influence of MFG size on milk composition analysis methods. Nevertheless, commonly used laser diffraction systems have never been thoroughly validated for size distribution measurements in human milk. Here, we introduce a new method for determining the size distribution of milk fat globules in human milk, using 3D confocal laser scanning microscopy (CLSM) in combination with fluorescent labeling of MFGs. We validate and compare 3D CLSM to laser diffraction (Mastersizer 2000, Malvern Panalytical), using polystyrene microsphere size standards. Next, we apply both methods to evaluate MFG size distributions in human milk. We show that 3D CLSM can be used to obtain more accurate size distributions between 500 nm and 10 μm compared to laser diffraction. Importantly, MFG size distributions obtained with 3D CLSM contain no secondary population around 1 μm, in contrast to laser diffraction measurements. This suggests that the bimodal MFG distribution obtained by laser diffraction can be an artifact of the built-in fitting algorithm, instead of an actual feature of human milk. This work demonstrates that care should be taken when interpreting size distributions of MFGs measured with laser diffraction and that 3D CLSM is an accurate alternative for measuring size distributions in lactation and dairy research. [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]

The breakup of liquid films in high-speed flows is found in many applications. These include prefilming air blast atomization found in fuel injectors and shedding of droplet off of airfoils. In this work, a test rig has been developed and applied to study the breakup of water films from the trailing edge of an NACA 0012 airfoil placed in a high-speed air flow. The results provided reflect a new detailed dataset focused on air velocities above 75 m/s. Computational fluid dynamic (CFD) simulations were used to guide the development of the rig and the associated boundary and inlet conditions. In this work, air velocities up to 175 m/s were used with water films between 0.4 cm²/s and 3.6 cm²/s. The water film was introduced onto one surface through a series of 0.5 mm holes separated by 1 mm at a location 35 mm downstream of the leading edge of the vane. High speed video was used to document the sheet breakup behavior from the edge of the airfoil. Image analysis was used to identify the breakup length of ligaments formed. Laser diffraction was used 50 mm downstream of the trailing edge of the vane to determine the droplet size distribution and associated representative average diameters generated. A series of test conditions were run between 50 m/s and 175 m/s using multilevel factorial designed experiments. The results obtained were subjected to analysis of variance to generate correlations for breakup length and droplet representative diameters as a function of the conditions studied. The analysis was conducted on dimensionless versions of the variables studied to help connect the results to the physics of the situation. For example, rather than using air velocity to correlate the behavior, the Weber number (based on gas phase density and velocity) was used owing to its historical ability to describe liquid breakup processes. The results obtained are compared with other studies in the literature, and good agreement was found for the conditions at which a comparison could be made. It is observed that, for the conditions studied, liquid film thickness has little effect on the resulting droplet sizes--especially for the higher air velocity cases studied. The results also illustrate the sensitivity to choice of the characteristic length, which is generally consisted of trailing edge geometry or boundary layer thickness. In contrast, liquid film does influence the ligament breakup length, although the time to break up is less affected. Overall, the correlations developed provide engineering tools to help estimate ligament and drop size behavior for water films shed from airfoils in a high-speed flow. [ABSTRACT FROM AUTHOR]

Background: Almost all of the development and research actors in the field of optical physics come from universities. Meanwhile, at the SMA, MA and SMK levels, this field is very poorly understood. This is due to the limited knowledge of optical physics and its supporting technology owned by the teachers. Objective: With this continuous and continuous training, it is hoped that it can provide new insights about understanding lasers and their use for technology 4.0 and can utilize laboratories in schools at the SMA, MA and SMK levels. Method: In practice, this activity was carried out virtually via Zoom which was attended by teachers at the SMA, MA and SMK levels, and was filled by several Physics lecturers at Airlangga University in delivering material in the form of lasers, laser diffraction, and 3D printing technology. Results: Partners get information related to increasing knowledge of the use of lasers and diffraction phenomena that can be conveyed and demonstrated to students, as well as the use of 3D printing technology so that teachers can convey and increase students' interest in learning Physics. Conclusion: Physics teachers at the SMA, MA and SMK levels, especially in Gresik Regency, feel quite helped by this activity because it has provided updated knowledge and information related to understanding and mastering the basic principles and applications of using lasers with a very satisfied level of satisfaction of about 47.73%, a satisfied category of about 45.27%, and the remaining 7% choosing to be less satisfied. [ABSTRACT FROM AUTHOR]

Despite the development of the dental industry, the prevalence of dental hypersensitivity does not decrease but increases at a progressive rate. Given the above, the subject of our research was the development of dental medicinal films with micronized calcium hydroxyapatite under the trade name «Kalident Powder 100» (Kalichem, Italy) for the treatment of dental hyperesthesia and caries prevention. To establish the optimal method of calcium hydroxyapatite introduction into the dental film, it was necessary to study the influence of different dispersion mediums on the physicochemical characteristics of the substance under study. Purified water, ethyl alcohol 96%, polysorbate 80, glycerol, polyethylene oxide-400, propylene glycol, sunflower oil, vaseline oil were used as dispersion medium in the studies. Research of physico-chemical characteristics was performed both for the substance «Kalident Powder 100» separately and for its mixtures with the studied liquids and their combinations (in a ratio of 1:1). The following physico-chemical characteristics have been determined: disperse and diffraction analysis of particle size distribution, morphological description, linear dimensions, shape factor, volume coefficient, Martin and Ferret diameters, wettability. The results of crystallographic and disperse analysis have revealed the polydispersity of the substance «Kalident Powder 100» and its high ability to agglomerate, which may adversely affect the homogeneity of its distribution in the dental medicinal product. A study of the effect of different dispersion medium on the physicochemical characteristics of calcium hydroxyapatite has shown a positive effect of hydrophilic liquids on the wettability of powder particles, changes in their shape, size, and distribution in the studied samples. It has been established that the combination of the substance «Kalident Powder 100» with combined solvent systems containing purified water, polysorbate 80, glycerol, and PEO-400, allows achieving optimal shape and particle size of calcium hydroxyapatite with their uniform distribution throughout the liquid, which is also confirmed by the results of laser diffraction. The obtained results will be used in further research on the development of dental medicinal film.

The goal of this study was to investigate the soil particle-size distribution (PSD) and pore structure characteristics in the Kubuqi Desert in order to provide basic data for gaining insights into the soil-modifying properties of the local vegetation. Based on laser diffraction analysis, we measured the soil PSD and calculated the single and multi-fractal dimensions of the soils under typical artificial forest and natural grassland vegetation. The diameters, volumes and surface areas of the soil pores were determined via nitrogen adsorption experiments. The relationships between the fractal characteristics and pore structure parameters of the soil were investigated via redundancy analysis and stepwise regression. The clay content was less than 2.0%, and the sand content was greater than 75.0%. There was variability in the PSD and fractal dimension, which was mainly observed for the 0–20 cm, 20–80 cm, and 80–100 cm soil layers. In the 0–80 cm, the fine particle content, single fractal dimension (D), entropy dimension (D1), ratio of D1 to the capacity dimension (D1/D0), and correlation dimension (D2) were smaller for the forest soils than for the grassland soils. The fine particle (clay and silt) content of the 80–100 cm soil layer was approximately 37.8% higher for the Salix psammophila-8a than for the Salix psammophila-3a, and it was approximately 161.4% higher for the Populus popular-35a than for the Pinus sylvestris var. mongolica-8a. The silt content, D1, D1/D0, and D2 were significantly positively correlated with the specific surface area (SSA), total pore volume (TPV), and average pore diameter (APD) of the nanopores (p < 0.05, 0.01, or 0.001), and they were significantly negatively correlated with the percentage of the micropore volume (PMV) (p < 0.05 or 0.01). In the Kubuqi Desert, the fine particle content and fractal dimensions of the soil layer below the root zone of shrub and arbor vegetation increased with increasing stand age, but the trend was reversed in the shallower soil layers. The variability of the soil PSD characteristics was strongly correlated with the variability of the nanopore parameters on the microscopic scale, suggesting that the total pore volume, average pore diameter, and percentage of the micropore volume may be potential indicators of the soil structure and quality.

ABSTRACT: In this paper, the particle size distribution (PSD) and morphology for six different metal powders were measured and compared using a range of techniques which included laser diffraction, static imaging, and dynamic imaging. The metal powders were chosen from a diverse end-use (Metal Injection Moulding, Laser - Powder Bed Fusion, Electron Beam - Powder Bed Fusion, and Hot Isostatic Pressing) and varied in powder size distribution and morphology. While the results for particles that were predominantly spherical showed some general agreement for the measured PSD across the range of measurement techniques investigated, larger variation than industrial tolerances would allow was identified when comparing the results between the different measurement techniques. The technique did influence the measured PSD at times, with differences large enough to require compensation if used for critical applications with tight tolerances. For samples that had particle morphologies that deviated away from spherical (agglomerated, irregular, or satellited), the difference in the measured PSD was more significant when comparing the results from the different measurement techniques. This was due to the under/overestimation of the PSD due to the measurement principles of the system being employed. Thus, when reporting PSD, it is of paramount importance to align specification requirements, and the certification test methods, with the industrial controls (i.e., laser diffraction when used in production to tune air classification). If different instruments or techniques are to be used by a purchaser and supplier, any inherent bias must be understood. For morphology, static imaging tends to result in a higher measured value for sphericity and aspect ratio in comparison to dynamic imaging. This is believed to be due to the influence of orientation during measurement as well as the resolution of the optics.

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]