Evaluation Of Particle Size Distribution Research Articles

Sustainable Construction through Waste Transformation: An Investigation into Bricks Made from Biomedical Waste

Abstract: This study explores the innovative use of biomedical waste, including sterilization wrap, plastic syringe components, medical glass, and mixed biomedical waste, as alternative raw materials in the production of sustainable bricks. Given the environmental and health risks associated with the disposal of biomedical waste, repurposing these materials for brick manufacturing presents a viable solution for waste management and sustainability in construction. Through chemical analysis, particle size distribution evaluation, and testing of physical and mechanical properties, this research assesses the feasibility and impact of incorporating various ratios of biomedical waste into bricks. The results indicate that certain biomedical wastes, particularly medical glass, can enhance the bricks' compressive strength and reduce water absorption, making them comparable or superior to traditional bricks. This study not only highlights the potential for reducing landfill use and environmental pollution but also contributes to the development of eco-friendly building materials. Future work will focus on optimizing material mixtures, evaluating long-term performance, and assessing the environmental impact of these sustainable bricks. This research underlines the importance of interdisciplinary approaches in addressing environmental challenges, offering a promising avenue for waste management and sustainable construction practices.

Hydrometallurgical Processing of Chalcopyrite by Attrition-Aided Leaching

We report the investigation of a chalcopyrite leaching process that implements millimeter-sized glass beads that are stirred in the leach reactor to combine particle grinding, mechanical activation, and surface removal of reaction products. The paper focuses on demonstrating the impact of the so-called attrition-leaching phenomenon on the leaching rate of a chalcopyrite concentrate and provides a first understanding of the underlying mechanisms. For this purpose, we have compared the copper leaching yield for different configurations under controlled chemical conditions (1 kg of glass beads and 84 g of chalcopyrite concentrate in 2.5 L of H2SO4-H2O solution, pH = 1.3, Eh = 700 mV vs SHE, and T = 42 °C). On top of elemental analysis of the leach solution with time, we provide a full characterization of the solid residue based on X-ray diffraction, elemental analysis, and sulfur speciation. We demonstrate that glass beads led to a remarkable enhancement of the leaching rate in conditions where particles were already passivated by simple leaching and even when large amounts of solid products (elemental sulfur and jarosite) were present. An in-depth evaluation of particle size distribution showed that particle breakage occurred during a rather short time (a few hours) at the beginning of the runs, transforming the initial particles with d4/3 = 30 μm to finer particles with d4/3 = 15 μm. Then, particle breakage almost stopped, while an attrition phenomenon was evidenced, inducing the formation of very fine particles (<1 μm) and aggregates concomitantly with copper leaching.

Rapid evaluation of particle size distribution using image analyzer with machine learning

Particle size distribution of soil is often evaluated by “the method for particle size distribution of soils (JIS A 1204)”. This method requires long sieving time and accurate mass measurement of sieved soils, resulting rapid evaluation of in-situ soil characteristics and admission decision of soil classification difficult. Image analysis using an image analyzer, developed by Marui Co. and named “Sand measure”, has been applied for rapid evaluation. The method holds the error generated by the overlaps of soil particles. We have applied machine learning with expanding the input data to image analyzer for reducing the error. The machine learning is installed in the model composed of Convolution Neural Network. The machine learning reduces the error by about 40 % of the results evaluated by test data. Maximum reduction in error is about 78 % in test data. The image analyzer with machine learning can be applicable for rapid evaluation of particle size distribution.

Evaluation of particle size distribution, mechanical properties, microstructure and electrochemical studies of AA1050/fly ash metal matrix composite

ABSTRACT The mechanical properties and corrosion studies of AA 1050 metal matrix composite reinforced with varying weight fractions of fly ash were investigated. The fly ash weight fractions selected for this study were 2.5 wt%, 5 wt%, 7.5 wt%, and 10 wt%. This research was undertaken to investigate the effect of fly ash particulates on cast AA 1050 matrix composite. The cast samples’ microstructural analysis showed uniform dispersion of the fly ash particles in the 7.5 wt% samples and fairly uniform distribution of the fly ash particles in both the 2.5 wt% and 5 wt% samples. The investigation into the mechanical properties of the samples showed that the ultimate tensile strengths were 75.94 Mpa, 86.35 Mpa, 89.75 Mpa, 92.5 Mpa, and 86.14 Mpa for the base metal, 2.5 wt%, 5 wt%, 7.5 wt%, and 10 wt% composites, respectively. The microhardness analysis revealed an increase in the microhardness values, which was highest for the 7.5 wt% sample. The corrosion studies showed that the corrosion rate was 0.039 mm/yr, 0.013 mm/yr, 0.071 mm/yr, 0.021 mm/yr, 0.051 mm/yr for the base metal, 2.5 wt%, 5 wt%, 7.5 wt%, and 10 wt% composites, respectively. The SEM micrographs revealed pitting as the predominant corrosion mechanism.

Towards Automated Electron Microscopy Image Segmentation for Nanoparticles of Complex Shape by Convolutional Neural Networks

In this contribution different ways are explored with the aim to generate suitable training data for ‘non-ideal’ samples using various approaches, e.g., computer-generated images or unsupervised learning algorithms such as generative adversarial networks (GANs). We used these data to train simple CNNs to produce segmentation masks of SEM images and tested the trained networks on real SEM images of complex nanoparticle samples. The novel use of CNN for the automated analysis of the size of nanoparticles of complex shape and with a high degree of agglomeration has proved to be a promising tool for the evaluation of particle size distribution on a large number of constituent particles. Further development and validation of the preliminary model, respectively larger training and validation data sets are necessary.

Evaluation of particle size distribution and mechanical properties of mineral waste slag as filling material

The resource utilization of solid waste in civil engineering is an essential direction of environmental governance. This study systematically investigated the feasibility of mineral waste slag as subgrade filler. The optimal compaction parameters of the waste slag were determined. The effects of different factors on the particle size distribution and mechanical properties of mineral waste slag were evaluated, and the construction parameters of the waste slag were recommended. The results show that when the coarse grain content (CGC) increases from 20% to 80%, the optimal moisture content of the mineral waste slag reduces from 13.03% to 10.50%. The CGC and compactive effort have a greater effect on the particle size distribution and mechanical properties of waste slag. The unconfined compressive strength of the sample reaches a maximum of 0.687 MPa when CGC is 50%. The recommended CGC of waste slag is about 50% in practical engineering, and the moisture content should be strictly controlled.

A novel hyperspectral microscope imaging technology for rapid evaluation of particle size distribution in matcha

Hyperspectral microscope imaging (HMI) technology as a novel approach was proposed to evaluate physical characteristics of matcha. Particle size distribution as one of the significant physical characteristics was investigated. Data fusion which integrated of textural features from images at 524 nm and key spectral features selected by competitive adaptive reweighed sampling (CARS) were as the raw data for modeling. Models were optimized by cross-validation. Results showed that the performance of models was improved with data fusion. The best ANN models with data fusion were achieved with Rp (correlation coefficient in prediction set) of 0.8020 for D10, 0.8414 for D20, 0.8238 for D30, 0.8124 for D40, 0.8058 for D50, 0.8157 for D60, 0.7643 for D70, 0.7360 for D80, and 0.6313 for D90, respectively. This work demonstrated that HMI technology as a rapid, accurate and high effective protocol has great potential in predicting particle size distribution in matcha powder.

Evaluation of particle size distribution of granular blasting materials based on the fractal theory

The particle size distribution of granular blasting materials has a vital influence on the filling quality of earth-rockfill dams. The engineering experience-based method used to evaluate the particle size distribution has shortcomings at both the theoretical and practical aspects. This article proposes a new evaluation method based on the fractal theory. Grading sieve tests on granular materials, mass fractal analysis of particle size distribution, and a probability distribution model test of the characteristic parameters are used to revise the functional relationships between the fractal dimension D and the uniformity coefficient/curvature coefficient ( Cu/ Cc) of the grading curve. The feasibility of using D to evaluate the particle size distribution and the optimal fine grain content is then analyzed and determined. According to the results, the geometric shapes of the granular blasting materials have fractal characteristics, and their particle size distribution has a fractal distribution. The ranges of D where the rockfill and transition materials have a good particle size distribution are D = 2.254–2.529 and D = 2.358–2.559, corresponding to optimal fine grain content of 1.953%–11.805% and 10.268%–23.123%, respectively. Fractal dimension has a solid theoretical basis and strong practical applicability as an evaluation index for the particle size distribution of granular blasting materials.

Spouted bed drying on inert particles: Evaluation of particle size distribution of recovered, accumulated and elutriated powders

The performance of a spouted bed in drying a liquid suspension of calcium carbonate was evaluated through the analysis of particle size distributions of the products recovered from different parts of the dryer. The effects of the air temperature and paste feed flow rate on the particle size distributions and mean sizes were investigated. Depending on the drying conditions, solid mass fractions from 11 to 53% were collected at the cyclone underflow, from 2 to 8% were retained in the filter and from 23 to 34% accumulated in the drying vessel. The results provide compelling evidence that dried powder is highly heterogeneous in size. The sizes of particle’s clusters accumulated in the dryer column and collected in the cyclone underflow were enlarged by increasing the paste feed flow rate. The mean sizes of accumulated material varied from 3.7 to 47.1 μm. The sizes of powder elutriated in the cyclone overflow and collected in the cyclone underflow ranged respectively from 0.95 to 1.4 μm, and from 2.6 to 7.0 μm.

INVESTIGATION OF CHARACTERISTICS OF SPECIAL POWDERS AND MATERIALS PRODUCED BY MEANS OF SELECTIVE LASER MELTING

The article presents the results of characterization of special powders of metal alloys and materials produced from these powders by selective laser melting (SLM), including comparative analysis of powders produced using VIGA technology. It is noted the importance of a complex study that includes not only a statistical evaluation of particle size distribution of the powders (preferably, by the method of laser diffraction), but also image analysis providing information on the particles’ shape influencing the powders’ flowability. It is shown that the size distribution and shape metrics for nickel refractory alloys and stainless steel powders obtained at the Powder Metallurgy Institute of the National Academy of Sciences of Belarus are at the level of the best foreign analogues. The influence of powder chemical composition on the mechanical properties of SLM samples is considered. The presence of oxygen and undesirable impurities, as a rule, decreases the strength and tensile strain. It is noted that SLM provides extremely wide opportunities for the formation of complex geometric structures with close to full density. Subsequent thermal or thermal and mechanical processing allows reduction of stresses arising during the SLM, densification of products (if necessary) and regulation of their structure and properties. The prospects of applying the backscattered electron diffraction (EBSD) for analysis of the material structure evolution during SLM and subsequent processing are shown. It is noted that products obtained by the SLM from the powders of special alloys exhibit mechanical properties at a level, and in some cases even exceeding the properties of these alloys produced by traditional and other additive technologies.

A fractal evaluation of particle size distributions in an eolian loess-paleosol sequence and the linkage with pedogenesis

The changes of soil particle size distributions (PSDs) can be used as a proxy for soil development intensity and an indicator of soil formation processes. The fragmentation fractal dimensions can describe PSDs of soils in a single parameter. The objective of this research is to use mass-based fragmentation fractal dimension models to describe PSDs and evaluate the relationship between the fragmentation fractal dimension values (DF) and pedogenesis in loess-paleosol. Based on the theory of fragmentation fractal dimension, particle size data from 837 eolian loess samples from the lower part of Chaoyang section uniform loess deposits were analyzed with mass-based models using linear regression and piecewise linear regression. A single power-law exponent can characterize the PSDs across the domain of 0.1–54.4 μm. The trend of fragmentation fractal dimension values is consistent with chemical weathering indices, magnetic susceptibility, and <1 μm clay contents. The DF value of PSDs can be used to assess the degree of particle fragmentation and intensity of pedogenesis for loess-paleosols. A paleosol has a greater DF value than a loess; indicating that the greater the DF value, the greater the effect of energy events that have occurred. Loess particles in paleosols were fragmented to finer particles with an average median grain size (φ = 6.21 ± 0.24, CV = 3.94%) and were poorly sorted to very poorly sorted (So = 1.922 ± 0.128) due to strong pedogenesis under a prominent warm-wet climate. In contrast, particles in loess experienced fewer fragmentations and had a greater average median grain size (φ = 5.89 ± 0.35, CV = 5.89%) due to weak pedogenesis under prominent cold-dry climate. These results confirm the use of fractal characteristics to reflect the loess particle size reduction process. Two domains within the 0.1–54.4 μm domain, F1 and F2, were identified where power-law scaling was applicable. The close transition point from F1 to F2 is 7.64 ± 1.21 μm. The fragmentation fractal dimensions of the two domains decreased in the order: DF1 (close to 3) > DF2 (close to 2). The energy dissipation for fragmenting larger particles from coarse silt (CSI) to fine silt (FSI) is identified in the volume and for fragmenting smaller particles from fine silt (FSI) to clay (CL) it is substantially on the surface. This research indicated that fragmentation fractal model is a good descriptor for the PSDs and DF can be a value quantifying the intensity of loess-paleosol pedogenesis.

Evaluation of particle size distribution of aggregates in asphalt concrete by means of image analysis software

Application of numerical calculations in the design process of hydrodynamic torque converter

Multimodal Dispersion of Nanoparticles: A Comprehensive Evaluation of Size Distribution with 9 Size Measurement Methods.

Evaluation of particle size distribution (PSD) of multimodal dispersion of nanoparticles is a difficult task due to inherent limitations of size measurement methods. The present work reports the evaluation of PSD of a dispersion of poly(isobutylcyanoacrylate) nanoparticles decorated with dextran known as multimodal and developed as nanomedecine. The nine methods used were classified as batch particle i.e. Static Light Scattering (SLS) and Dynamic Light Scattering (DLS), single particle i.e. Electron Microscopy (EM), Atomic Force Microscopy (AFM), Tunable Resistive Pulse Sensing (TRPS) and Nanoparticle Tracking Analysis (NTA) and separative particle i.e. Asymmetrical Flow Field-Flow Fractionation coupled with DLS (AsFlFFF) size measurement methods. The multimodal dispersion was identified using AFM, TRPS and NTA and results were consistent with those provided with the method based on a separation step prior to on-line size measurements. None of the light scattering batch methods could reveal the complexity of the PSD of the dispersion. Difference between PSD obtained from all size measurement methods tested suggested that study of the PSD of multimodal dispersion required to analyze samples by at least one of the single size particle measurement method or a method that uses a separation step prior PSD measurement.

Evaluation of particle size distributions produced during ultra-violet nanosecond laser ablation and their relative contributions to ion densities in the inductively coupled plasma

Relative contributions to ion densities in the inductively coupled plasma (ICP) of particles of various sizes produced by laser ablation (LA) were investigated. Particles generated by 266nm, ns LA of BaF2, CaF2, and a scandium aluminum alloy, characterized using SEM, consisted of hard and soft agglomerates, spherical particles, and irregularly-shaped particles. Although soft agglomerates and spherical particles were common to aerosols generated by LA in all cases, hard agglomerates appeared to be unique to the scandium aluminum alloy, while irregularly-shaped exfoliated particles were unique to the calcium and barium fluoride windows. The spatial distributions of Ca, Ba, and Sc ions in the ICP were determined from laser-induced fluorescence images taken with filters of pore sizes from 1–8μm added in-line to the transport tube upstream from the ICP. In all cases, a significant fraction of the ions formed in the ICP originated from micron-sized particles. Differences in the penetration depths of nanometer-sized agglomerates and micron-sized particles were about 2mm for Ca and 1mm for Ba. Differences in the penetration depths of nanometer and micron-sized agglomerates observed in the case of aluminum scandium were much less significant. This suggests that micron-sized hard-agglomerates and nanometer-sized soft-agglomerates experience very similar vaporization patterns. Additionally, there was evidence that flow patterns in the transport tube affect the trajectories of particles entering the plasma.

Reactivation by Steam Hydration of Sorbents for Fluidized-Bed Calcium Looping

The present study addresses steam hydration as a tool for reactivation of the CO2 capture potential of spent limestone-based sorbents from fluidized-bed calcium looping systems. A reference, high-calcium, reactive limestone was deactivated by carrying out lab-scale fluidized-bed calcium looping process tests (calcination at 940 °C in a 70% CO2 atmosphere and carbonation at 650 °C in a 15% CO2 atmosphere) and then steam-hydrated (at 250 °C in a 50% steam atmosphere) in the same fluidized bed, for times ranging from 10 to 60 min. Online flue gas analysis, continuous capture of the elutriated fines, and evaluation of particle size distribution were performed during additional calcium looping process tests after sorbent reactivation. Thermogravimetric analysis, scanning electron microscopy, and porosimetry were directed to characterize the microstructural features of the spent and steam-hydrated sorbents. Moreover, the different materials were subjected to ex situ impact fragmentation tests. In this way, it w...

Use of dynamites, water-gels and emulsion explosives in Sri Lankan quarrying/mining practice

In the Sri Lankan mining and quarrying industry, gelatine dynamite has been the widely used explosive for rock blasting purposes. In the recent past, it has been phased out and replaced by locally manufactured Water-gels(WG). So far, there had been only a very few tests conducted to assess the suitability and to evaluate the performance of this explosive with other available explosives. Complaints made by the users of Water-gels have been a cause of concern and prompted research to be conducted with the aim of evaluating the performance of Dynamites, Water-gels and Emulsion explosives with the measurement of major performance indicators in local mining and quarrying practice. In this research, performance comparison of WG, Dynamite and Emulsion explosives with regard to rock breakage in underground tunneling and in metal quarrying has been carried out. Comparison of fragmentation with the evaluation of particle size distribution in concrete block blasting using the three types of explosives has been one of the main tests. Gap sensitivity, density and the determination of velocity of detonation (VOD) has also been carried out. ENGINEER, Vol. 48, No.01, pp. 31-37, 2015

In-situ evaluation of particle size distribution of ZrO2-nanoparticles obtained by sol–gel

In this study the in-situ synthesis of zirconia via sol–gel was investigated in order to relate the influence of the processing parameters on particle size distribution. Zirconium n-propoxide was used as the precursor, n-propanol as solvent and several parameters were investigated, such as pH, reaction medium, synthesis time and temperature. The particle sizes and the polydispersion of colloidal dispersions were determined in situ using dynamic light scattering. In acetic medium, the particle size remained mostly below 100nm. With the introduction of NaCl, the maximum particle size reached 71nm. For other reaction media (HNO3 and without acid or base), the largest particle size was in the order of micrometers. The comparison of the different synthesis routes investigated did not enable us to observe one trend related to increased particle size when compared to reaction times in the synthesis of zirconia. This work aims to show how the reaction medium influence in obtaining a colloidal dispersion with nanometric sizes obtained from the sol–gel process.

Evaluation of Particle Size Distribution of Coal Gangue through Fractal Method in Dongkuang Mine, Heshan, China

The particle size distribution of coal gangue was obtained from a sieving experiment and the representative grading calculated using the statistical values of coarse grain content. A fractal method was proposed and fractal dimension D deduced based on the accumulated mass distribution function. The results indicate that when the value of D is between 1.89 and 2.63, coal gangues are well graded. The use of a fractal method can help to avoid errors associated with calculating grading parameters (Cu and Cc) in traditional theory, and the fractal dimension D can also be used to evaluate the compactability of coal gangues and other bulk materials.

Tuning Aerosol Particle Size Distribution of Metered Dose Inhalers Using Cosolvents and Surfactants

Objectives. The purpose of these studies was to understand the influence of cosolvent and surfactant contributions to particle size distributions emitted from solution metered dose inhalers (pMDIs) based on the propellant HFA 227. Methods. Two sets of formulations were prepared: (a) pMDIs-HFA 227 containing cosolvent (5–15% w/w ethanol) with constant surfactant (pluronic) concentration and (b) pMDIs-HFA 227 containing surfactant (0–5.45% w/w pluronic) with constant cosolvent concentration. Particle size distributions emitted from these pMDIs were analyzed using aerodynamic characterization (inertial impaction) and laser diffraction methods. Results. Both cosolvent and surfactant concentrations were positively correlated with median particle sizes; that is, drug particle size increased with increasing ethanol and pluronic concentrations. However, evaluation of particle size distributions showed that cosolvent caused reduction in the fine particle mode magnitude while the surfactant caused a shift in the mode position. These findings highlight the different mechanisms by which these components influence droplet formation and demonstrate the ability to utilize the different effects in formulations of pMDI-HFA 227 for independently modulating particle sizes in the respirable region. Conclusion. Potentially, the formulation design window generated using these excipients in combination could be used to match the particle size output of reformulated products to preexisting pMDI products.

Modeling, Simulation, and Experimental Evaluation of Particle Size Distribution in Stabilized Fluidized Bed Adsorption System

Fluidized beds containing solid particles of a wide size distribution is of significant practical importance. In such systems, the overall behavior depends on the opposing effect of mixing and classification. In the present work, the mixing and segregation behavior of liquid fluidized beds containing particles of different sizes is described mathematically. Particle size distribution (PSD) is studied in a glass column of 5 cm internal diameter and 250 cm length. Ion exchange resins were used as a solid phase with a particle size range of 50 to 650 µm. The bed was fluidized at constant and low water flow velocity and the particle size measurement was carried out at different locations over the column length by analytical scanning electron microscope. Particle size fractionation data obtained by Malvern Mastersizer-2000, version 5.4, was utilized in the solution of developed model equations to obtain PSD. It is apparent that the mixing model along with the classification model represents better results than any other model given by various researchers in the literature. The proposed model is in good agreement with the PSD data given by Malvern particle size analyzer.