Effect Of Particle Concentration Research Articles

Nano-hydroxyapatite Pickering emulsions as edible mayonnaise-like food sauce templates: A novel approach for food design

Pickering emulsions have the potential to enhance product stability and provide opportunities to create functional solutions that align with labelling requirements. The present work aims to develop Pickering emulsions stabilised by nano-hydroxyapatite (n-HAp) particles to replace traditional mayonnaises. The study addresses the effect of n-HAp solid particle concentration (5–15 wt%) and oil-water ratio (50:50, 60:40, 70:30, and 80:20, v/v) on emulsion stability, rheological properties, and oxidative stability. The results indicate that the produced Pickering emulsions have good stability for the tested period of 90 days, except for the 80:20 o/w emulsion that undergone a prompt quick phase separation. The Pickering emulsions produced with higher n-HAp concentration or oil content have a semi-solid structure, rendering them desirable options for replicating the texture of traditional mayonnaises. Regarding oxidative stability, the Pickering emulsions showed considerably improved stability compared to commercial mayonnaises (∼13 times higher), suggesting higher resistance to peroxidation and a longer shelf-life.

Effects of particle size and particle concentration of poly (ethylene‐co‐methacrylic acid) on properties of epoxy resin

AbstractSelf‐healing polymers have been developed to improve durability and reduce costs associated with maintenance during service. The addition of thermoplastics to thermosets to produce mendable polymers appears as a promising self‐healing technique. In this study, poly (ethylene‐co‐methacrylic acid) (EMAA) was added to epoxy resin and the effects of EMAA addition on epoxy properties were evaluated. Specimens with two different contents of thermoplastic and particles sizes were manufactured. A two‐level full factorial experimental design was used to evaluate the effect of particle size and particle content on properties of epoxy modified with addition of EMAA. Tensile tests and dynamic mechanical analysis (DMA) were used and the evaluated responses were tensile strength, modulus of elasticity, and glass transition temperature (Tg). X‐ray computed tomography (XCT) was used to investigate particle size and concentration after manufacturing. It was found that the particle concentration has greater effects on stress–strain behavior of epoxy while Tg was not significantly affected by neither of the analyzed entrance variables.

Effect of particle size and concentration of Al2O3 on the corrosion behavior of silane-Al2O3/MWCNT double-layer coating: towards protecting the AZ91 magnesium alloy

Effect of particle size and concentration of Al2O3 on the corrosion behavior of silane-Al2O3/MWCNT double-layer coating: towards protecting the AZ91 magnesium alloy

Fabrication, characterization and application of Pickering emulsion gels stabilized by defatted grape seed powder

The feasibility of defatted grape seed powder (DGSP) stabilizing Pickering emulsion gels as butter substitute was investigated. The Pickering emulsion gel was constructed using DGSP through high-speed homogenization, and the effects of particle concentration (c) and oil-phase (Medium chain triglyceride) volume fraction (φ) on its structure and properties were investigated. Its application as a butter substitute was also evaluated. The results showed that DGSP had various particle shapes, a wide particle size distribution (3–130 μm), and a three-phase contact angle of 128.9 ± 2.3°. The O/W Pickering emulsion gels with φ ≥ 60% could be obtained at c ≥ 2%. The droplet diameter was negatively correlated with c and positively correlated with φ, while the gel strength was positively related to c and φ. The resulting emulsion gel demonstrated solid-like viscoelastic behavior and pseudoplasticity, and had the potential to serve as a butter substitute. The results can promote the application of grape seeds in food.

Fully coupled discrete element method for graded particles transport in pipes

Hydraulic conveying of graded particles is much more complex than that of uniform particles but is not fully understood. A fully coupled computational fluid dynamics–discrete element method model is established for the hydraulic conveying of graded particles, which integrally considers the particle–fluid and particle–particle interactions and turbulence modulation from particles. The proposed model accounts for the stochastic motion of particles by the discrete random walk method and applies the diffusion averaging algorithm to obtain particle concentration in arbitrary cells for smooth and cell-independent data fields on unfavorable cells (fluid cell size ≤ particle size). The particle–fluid drag force is applied to slurry flows through densely packed particle beds due to the consideration of porosity modification. The proposed model well performs in simulating the hydraulic conveying of dense graded particles. Dynamics in slurry mixtures of bi-disperse particles are investigated regarding different particle size compositions. The results show obvious stratification between coarse and fine particles, e.g., fine particles settling at the pipe bottom elevate the coarse particles and form a “lubrication layer” with high velocity. The torque caused by particle–particle/wall contact is greater than the torque caused by the fluid. The pipe cross section is divided into four regions according to the particle angular velocity. The effect of particle concentration on liquid motion is small because the difference in local particle concentration is relatively small, but the maximum pressure drop corresponds to a critical particle size composition.

Fine excipient materials in carrier-based dry powder inhalation formulations: The interplay of particle size and concentration effects

The contributions of fine excipient materials to drug dispersibility from carrier-based dry powder inhalation (DPI) formulations are well recognized, although they are not completely understood. To improve the understanding of these contributions, we investigated the influences of the particle size of the fine excipient materials on characteristics of carrier-based DPI formulations. We studied two particle size grades of silica microspheres, with volume median diameters of 3.31 μm and 8.14 μm, as fine excipient materials. Inhalation formulations, each composed of a lactose carrier material, one of the fine excipient materials (2.5% or 15.0% w/w), and a drug (fluticasone propionate) material (1.5% w/w) were prepared. The physical microstructure, the rheological properties, the aerosolization pattern, and the aerodynamic performance of the formulations were studied. At low concentration, the large silica microspheres had a more beneficial influence on the drug dispersibility than the small silica microspheres. At high concentration, only the small silica microspheres had a beneficial influence on the drug dispersibility. The results reveal influences of fine excipient materials on mixing mechanics. At low concentration, the fine particles improved deaggregation and distribution of the drug particles over the surfaces of the carrier particles. The large silica microspheres were associated with a greater mixing energy and a greater improvement in the drug dispersibility than the small silica microspheres. At high concentration, the large silica microspheres kneaded the drug particles onto the surfaces of the carrier particles and thus impaired the drug dispersibility. As a critical attribute of fine excipient materials in carrier-based dry powder inhalation formulations, the particle size demands robust specification setting.

Baffle effect of exposed WC particles in the clearance on slurry erosion behavior of cemented carbide surface

Erosion damage of clearance fits is the major factor for the failure of metal-to-metal screw motors. In this study, the slurry erosion behavior of the WC-based laser cladding layer was investigated. It aimed to explore the effect of SiO2 particle concentration on the laser cladding layer. The experimental results indicate that the WC-based laser cladding layer exhibits excellent erosion resistance across various particle concentration environments. The presence of the 'baffle effect' resulted in the cladding layer demonstrating enhanced erosion resistance, particularly at high particle concentrations. The 'baffle effect' refers to exposed WC particles hindering the movement of SiO2 particles. As SiO2 particles continuously impact the clearance material surface, much of the matrix on the cladding surface is removed. The presence of remaining WC particles on the clearance material can impede the impact of particles in the slurry. The current results aim to offer experimental support for future investigations of surface strengthening methods for metal-to-metal screw motors.

Influence of graphene on corrosion properties of micro arc oxidation coatings on 7075 aluminum alloy

AbstractThis study uses 7075 aluminum alloy as the base material and employs micro arc oxidation technology to prepare ceramic coatings with different concentrations of graphene particles on the surface of the 7075 aluminum alloy. The effects of graphene particle concentration on micro arc oxidation behavior and coating performance were investigated through X‐ray diffraction, scanning electron microscope, electrochemical testing, and other performance characterization methods. The research results show that the addition of graphene particles helps to promote the transformation of metastable γ‐Al2O3 to stable α‐Al2O3, thereby enhancing the corrosion properties of the coating. When the concentration of graphene particles is 3 g/L, the prepared micro arc oxidation coating has the maximum thickness and hardness, which are 17.13 µm and 886.76 HV0.3, respectively, while the porosity and roughness are the smallest, which are .39 µm and 4.79%, respectively. Electrochemical test results show that the self‐corrosion current density is the smallest at this concentration, which is 2.323 × 10−9A/cm2. Therefore, the addition of graphene particles can effectively improve the corrosion properties of 7075 aluminum alloy.

Study on hardness and corrosion resistance of Co-Mo-P/ZrO2 composite coating electrodeposited on Q345 steel

Co-Mo-P/ZrO2 composite coating was prepared on the surface of Q345 steel by electrodeposition technology, and the effect of different ZrO2 particle concentrations on the surface morphology, chemical composition, thickness, microstructure and mechanical properties of the composite coating was investigated. The results show that different composite coatings prepared by changing the concentration of ZrO2 particles in the bath show aggregated cellular surface morphology, which is composed of Co, Mo, P, Zr, and O elements. With the concentration of ZrO2 particles increasing from 4 g/L to 20 g/L, the average grain size and the amount of ZrO2 particles incorporated both decrease first and then increase. Moreover, along with the increase in concentration of ZrO2 particles, the hardness and scratch resistance of the composite coating both show a trend of increasing first and then decreasing. However, changing the concentration of ZrO2 particles has no obvious effect on the grain structure and growth orientation of the composite coating. When the concentration of ZrO2 particles is 12 g/L, the surface of the composite coating is relatively dense with an average grain size of 40.78 nm and (200) crystal face preferred orientation. More ZrO2 particles are incorporated on the surface and boundary of the grain aggregation, which plays an obvious dispersion strengthening effect. The hardness of the composite coating reaches 580.2 HV, showing good scratch and corrosion resistance.

Investigation on the effect of particle parameters on the erosion and erosion prediction model of the Pelton turbine

The Pelton turbine will play a massive role in China's water conservancy and power generation development process. In practical engineering applications, sediment will erode the components of the Pelton turbine when they come into contact, threatening the safe and stable operation of the unit. Therefore, based on the Eulerian–Lagrangian method, this study analyzes the effects of particle size, concentration, and position angle on the degree and distribution of erosion of each component without considering the cavitation effect of the flow. The results show that the larger the particle size, the more concentrated the distribution, and the more severe the abrasion caused on the spray needle and water bucket. However, the degree of nozzle erosion weakens, and the erosion area increases. It was also found that the higher the concentration, the more severe the abrasion caused to each component. When the jet completely hits the position on the bucket, due to the low impact speed, the impact angle remains almost unchanged, resulting in less erosion. Finally, the classic Finnie model was refined by adjusting the average erosion rate, particle size, concentration, and rotation angle. This modification yielded an enhanced model, mainly showcasing improved performance for moderate particle sizes.

Investigation of heterogeneous condensation flow characteristics in the steam turbine based on homogeneous-heterogeneous condensation coupling model using OpenFOAM

Non-equilibrium condensation can result in thermodynamic losses within turbine stages and potentially cause blade erosion. During turbine operation, steam frequently carries foreign particles, which can influence non-equilibrium condensation. However, there is a lack of systematic research on the specific effects of these particles on the condensation processes. This paper firstly utilizes OpenFOAM to establish a homogeneous-heterogeneous condensation coupling model, which is validated for accuracy through experimental data. Secondly, it investigates the effects of NaCl particle concentration and radius on the heterogeneous condensation process in Laval nozzles and Dykas cascades. Finally, it examines the relationship between the kinetic energy ratio, condensation loss ratio, wetness fraction ratio, and particle concentration and radius in turbine cascades to explore the optimal method for reducing the impact of condensation phase change in steam turbines. The results indicate that nucleation rate decreases as particle radius decreases and concentration increases in Laval nozzle. However, the effect of concentration on wetness is non-linear; as concentration increases, wetness initially decreases before increasing. In comparison to homogeneous condensation within Dykas cascades, when the introduced particle radius is 1 × 10−9 m and the concentration is 1014kg−1, the kinetic energy increases by 2.93%, condensation loss decreases by 22.91%, and wetness fraction decreases by 23.64%.

Effect of Particle Concentration on the Microstructure and Properties of Electrodeposited Nickel–Diamond Composite Coatings

For the purpose of improving the wear properties of Ni composite coatings, diamond particles were co-electrodeposited into Ni–diamond composite coatings. The effect of diamond particle concentration in the electrolyte on the surface morphology, microstructure, and wear properties of Ni–diamond composite coatings was investigated. The electrodeposition behaviors of the composite coatings were simulated by COMSOL5.6. The results showed that the content of diamond particles in the coating was elevated by increasing the particle concentration in the electrolyte. The formation of [200] fiber texture was blocked and concurrently brought about crystallite refinement of the Ni deposits by the embedded particles. The COMSOL simulation findings indicated that embedded particles influenced the microstructure of the Ni deposits through processes such as heterogeneous nucleation, rearrangement, and concentration of local current density. The synergistic effect of the tailored microstructure and embedded particles substantially enhanced the wear resistance of the coating. By increasing the particle concentration in the electrolyte, the wear resistance of the coating was gradually enhanced, and the coating electrodeposited at 16 g/L possessed the lowest friction coefficient and the smallest profile of wear scratch owning to the strengthened synergistic effect.

Transport and retention of functionalized graphene oxide nanoparticles in saturated/unsaturated porous media: Effects of flow velocity, ionic strength and initial particle concentration

The widespread use of nanomaterials has raised the threat of nanoparticles (NPs) infection of soils and groundwater resources. This research aims to investigate three parameters including flow velocity, ionic strength (IS), and initial particle concentration effects on transport behavior and retention mechanism of functionalization form of graphene oxide with polyvinylpyrrolidone (GO-PVP). The transport of GO-PVP was investigated in a laboratory-scale study through saturated/unsaturated (Saturation Degree = 0.91) sand columns. Experiments were conducted on flow velocity from 1.20 to 2.04 cm min−1, initial particle concentration from 10 to 50 mg L−1, and IS of 5–20 mM. The retention of GO-PVP was best described using the one-site kinetic attachment model in HYDRUS-1D, which accounted for the time and depth-dependent retention. According to breakthrough curves (BTCs), the lower transport related to the rate of mass recovery of GO-PVP was obtained by decreasing flow velocity and initial particle concentration and increasing IS through the sand columns. Increasing IS could improve the GO-PVP retention (based on katt and Smax) in saturated/unsaturated media; katt increases from 2.81 × 10−3 to 3.54 × 10−3 s−1 and Smax increases from 0.37 to 0.42 mg g−1 in saturated/unsaturated conditions, respectively. Our findings showed that the increasing retention of GO-PVP through the sand column under unsaturated condition could be recommended for the reduction of nanoparticles danger of ecosystem exposure.

Self-pinning colloids on rough surface

Self-pinning colloids are integral to multiple applications from ink-jet printing to diagnostic platforms. The commercial surfaces involved in these applications are inherently rough and to mimic the same, we probe the self-pinning mechanistic using a model system of colloidal (sessile) droplet desiccating over a homogeneously rough surface having root-mean-square roughness, Sqnm∼0.36nm;(0<Sq<1). Further, the interplay of the particle diameter dnm∼460;30)with the substrate roughness induced length-scale on the evaporation modes of these desiccating colloidal droplets has been investigated with extensive experiments. The second parametric variation outlined the effect of varied particle concentration (ϕ,ww%∼0.05,0.1,1) on the pinning-de-pinning transition of the contact line during evaporation. These are characterised and quantified by contact angle goniometry and a general map of evaporation modes is proposed for such evaporating colloidal droplets induced by self-pinning of the dispersed colloids.

A nudge over the relaxation plateau: effect of pH, particle concentration, and medium viscosity on the AC induction heating efficiency of biocompatible chitosan-coated Fe3O4 nanoparticles

The effects of pH, MNP concentration, and medium viscosity on the magnetic fluid hyperthermia (MFH) properties of chitosan-coated superparamagnetic Fe3O4 nanoparticles (MNPs) are probed here. Due to the protonation of the amide groups, the MNPs are colloidally stable at lower pH (∼2), but form aggregates at higher pH (∼8). The increased aggregate size at higher pH causes the Brownian relaxation time (τ B) to increase, leading to a decrease in specific absorption rate (SAR). For colloidal conditions ensuring Brownian-dominated relaxation dynamics, an increase in MNP concentrations or medium viscosity is found to increase the τ B. SAR decreases with increasing MNP concentration, whereas it exhibits a non-monotonic variation with increasing medium viscosity. Dynamic hysteresis loop-based calculations are found to be in agreement with the experimental results. The findings provide a greater understanding of the variation of SAR with the colloidal properties and show the importance of relaxation dynamics on MFH efficiency, where variations in the frequency-relaxation time product across the relaxation plateau cause significant variations in SAR. Further, the in vitro cytotoxicity studies show good bio-compatibility of the chitosan-coated Fe3O4 MNPs. Higher SAR at acidic pH for bio-medically acceptable field parameters makes the bio-compatible chitosan-coated Fe3O4 MNPs suitable for MFH applications.

Experimental Study on the Explosion Parameters of n-Decane Aerosol under Saturated Vapor Pressure.

This research aims to conduct a comprehensive investigation and analysis of the effects of particle size and concentration on crucial explosion parameters in n-decane aerosols. Two sets of n-decane aerosols with different concentrations were initially measured, with Sauter mean diameters of 22 and 38 μm, respectively. These measurements served as the foundation for understanding the impact of the particle size on explosion parameters. Subsequently, experiments were performed on n-decane aerosols with various concentrations, utilizing an ignition energy of 40.32 J. The analysis focused on critical explosion parameters including the lower flammability limit, explosion pressure, explosion temperature, and flame propagation delay time. Through thorough examination of the data obtained from these experiments, the research elucidated the relationship between n-decane concentration, particle size, and these explosion parameters.

Prediction of the aggregation rate of nanoparticles in porous media in the diffusion-controlled regime.

The fate and aggregation of nanoparticles (NPs) in the subsurface are important due to potentially harmful impacts on the environment and human health. This study aims to investigate the effects of flow velocity, particle size, and particle concentration on the aggregation rate of NPs in a diffusion-limited regime and build an equation to predict the aggregation rate when NPs move in the pore space between randomly packed spheres (including mono-disperse, bi-disperse, and tri-disperse spheres). The flow of 0.2M potassium chloride (KCl) through the random sphere packings was simulated by the lattice Boltzmann method (LBM). The movement and aggregation of cerium oxide (CeO2) particles were then examined by using a Lagrangian particle tracking method based on a force balance approach. This method relied on Newton's second law of motion and took the interaction forces among particles into account. The aggregation rate of NPs was found to depend linearly on time, and the slope of the line was a power function of the particle concentration, the Reynolds (Re) and Schmidt (Sc) numbers. The exponent for the Sc number was triple that of the Re number, which was evidence that the random movement of NPs has a much stronger effect on the rate of diffusion-controlled aggregation than the convection.

Transport and retention of silica nanoparticles in glass-bead columns: effects of particle size, type, and concentration of ionic species

Silica nanoparticles (SiO2 NPs) have garnered substantial attention as versatile additives in saline fluids, finding application in areas like environmental remediation, wastewater treatment, enhanced oil recovery, and carbon geo-sequestration. Despite their potential, the intricate interaction between electrolyzed nanoparticles and porous media remains inadequately researched in these contexts. This study delves into the pivotal yet underexplored aspect of silica nanoparticle absorption behavior within porous media, a key determinant of their practical effectiveness. The research focuses on silica particles with dimensions of 10 nm and 50 nm, synthesized via hydrolysis and condensation of tetraethyl orthosilicate (TEOS) in methanol. Employing packed glass bead columns as a surrogate for porous media, the study unravels the complex mechanisms governing nanoparticle transport and deposition. Comprehensive investigations encompass variations in particle sizes, ionic strength, and ionic species, resulting in the examination of 48 distinct flooding scenarios. UV/Vis spectrophotometry is used to quantify nanoparticle concentrations in effluents, elucidating their transport behavior within the porous media. Concurrently, pressure drop alterations across the media serve as indicators of particle plugging and changes in permeability. Intriguingly, specific conditions involving a nanofluid comprising 50 nm silica nanoparticles and 10,000 ppm of magnesium chloride exhibit pronounced permeability reduction, offering potential insights for optimizing applications. Particularly noteworthy is the unique reduction in silica particle retention on glass bead surfaces as salinity increases, especially in the presence of magnesium sulfate. A concentration of 5000 ppm magnesium sulfate induces a log-jamming mechanism, resulting in an amplified final-to-intermediate permeability ratio. Experimental outcomes align with observations from scanning electron microscopy, improving understanding of porous media retention mechanisms. This study contributes to a deeper understanding of interactions between nanoparticles and porous media, paving the way for enhanced application strategies.

Increasing particle concentration enhances particle penetration depth but slows down liquid imbibition in thin fibrous filters

The transport of particles within thin, porous media is a complex process which received growing attention due to its applications in filtration, printing and microfluidics devices. The effect of particles on liquid imbibition and particle clogging can reduce the performance and lifetime of these applications. However, these processes are still not clearly understood and are challenging to investigate. The goal of this study is to increase our understanding about the effect of particle concentration on the imbibition process in thin fibrous membrane filters. In this study, an Ultra-Fast Imaging NMR method is used to study the particle penetration inside nylon membrane filters for particle suspensions with varying particle concentrations (C0). The measurements revealed that increasing the particle concentration increases the particle penetration depth S(t) as governed by a Langmuir isotherm given by S(t)=l(t)(1+κC0)/1+κ(C0+Cb,m), with Cb,m the bound particles and κ the binding constant. Secondly, in droplet penetration, particles slow down liquid penetration in a Darcy like manner where effect on viscosity (η) and surface tension (σ) determine the penetration speed rather than changes within permeability (K0). The final liquid front (l), scaled according to l2∝σt/η. The particle penetration depths were verified using scanning electron microscopy images.

Design, development, and performance analysis of plate-plate hybrid magneto rheometer considering uniform radial magnetic flux

The current study presents a magnetic numerical simulation of a plate-plate magnetorheometer using the finite-element method. In this study, a magnetorheometer with the least number of coil turns has been proposed and developed to obtain a high and consistent magnetic flux density (0.68 T at 3A) along the radius of the magnetorheological fluid (MRF) zone. The possibility of radial migration of MRF is eliminated by the lack of a magnetic flux gradient along the MRF zone’s radius. After comparing the temperature rise in the magnetorheometer caused by resistive and viscous heating in the simulation and the experiment, it has been found that the temperature rise has a negligible effect on the MR fluid. When we conducted studies in hybrid mode—that is, shear plus compression mode—we found that, under the same operating conditions, the shear stress was significantly higher compared to when we only used shear mode. In the combined shear plus compression mode, it has been observed that the effects of particle concentration and compression velocity have a significant impact on the shear stress value.