Function Of Particle Size Research Articles

Chemical composition of microplastics floating on the surface of the Mediterranean Sea

The Mediterranean Sea is one of the most studied regions in the world in terms of microplastic (MP) contamination. However, only a few studies have analysed the chemical composition of MPs at the Mediterranean Sea surface. In this context, this study aims to describe the chemical composition as a function of particle size, mass and number concentrations of MPs collected in the surface waters of the Mediterranean Sea. The chemical composition showed a certain homogeneity at the Mediterranean Sea scale. The main polymers identified by Fourier Transform Infra-Red (FTIR) spectroscopy were poly(ethylene) (67.3 ± 2.4%), poly(propylene) (20.8 ± 2.1%) and poly(styrene) (3.0 ± 0.9%). Nevertheless, discrepancies, confirmed by the literature, were observed at a mesoscale level. Thus, in the North Tyrrhenian Sea, the proportion of poly(ethylene) was significantly lower than the average value of the Mediterranean Sea (57.9 ± 10.5%). Anthropic sources, rivers, or polymer ageing are assumed to be responsible for the variations observed.

Size-Dependent Morphology, Composition, Phase State, and Water Uptake of Nascent Submicrometer Sea Spray Aerosols during a Phytoplankton Bloom

The impact of sea spray aerosols (SSAs) on Earth’s climate remains uncertain in part due to size-dependent particle-to-particle variability in SSA physicochemical properties such as morphology, composition, phase state, and water uptake that can be further modulated by the environment relative humidity (RH). The current study investigates these properties as a function of particle size and RH, while focusing on submicrometer nascent SSA (0.1–0.6 μm) collected throughout a phytoplankton bloom. Filter-based thermal optical analysis, atomic force microscopy (AFM), and AFM photothermal infrared spectroscopy (AFM–PTIR) were utilized in this regard. AFM imaging at 20% RH identified five main SSA morphologies: prism-like, core–shell, rounded, rod, and aggregate. The majority of smaller SSAs throughout a bloom were rounded, while larger SSAs were core–shell. Filter-based measurements revealed an increasing organic mass fraction with decreasing SSA size. The organic matter is shown to primarily reside in a rounded and core–shell SSA, while the prism-like and rod SSA are predominantly inorganic salts (i.e., sodium chloride, nitrates, and sulfates) with relatively low organic content, as determined by AFM–PTIR spectroscopy. AFM phase state measurements at 20% RH revealed an increasing abundance of core–shell SSA with semisolid shells and rounded SSA with a solid phase state, as the particle size decreases. At 60% RH, shells of core–shell and rounded SSA uptake water, become less viscous, and their phase states change into either semisolid or liquid. Collectively, findings reveal the dynamic and size-dependent nature of SSA’s morphology, composition, phase states, and water uptake, which should be considered to accurately predict their climate-related effects.

In vitro applicability of mixed soy lecithin-based liposomes with added several lipophilic agents as novel delivery systems for delivery of quercetin

The study used highly lipophilic compounds to evaluate membrane physical and constitutional changes and vesicle stabilization of mixed soy lecithin (ML)-based liposomes. The in vitro bio-accessibility of novel quercetin (QU)-loaded ML-based liposomes as a function of particle size, polydispersity index (PDI), zeta potential (ZP), different membrane stabilizers, membrane fluidity and encapsulation efficacy (EE) was examined. Three different membrane systems, empty ML-based liposomes (E-LPs), squalene (SQ) loaded LPs (SQ-LPs), and SQ and a combination of β-sitosterol (βS) and stigmasterol (ST) loaded LPs (SQ-βS-ST-LPs), were developed based on optimized formulations using an extrusion method and used to encapsulate QU. The applicability of the ML-based liposomal carriers was tested by means of an in-vitro digestion procedure by applying a 2-phase static in- vitro model of the stomach and small intestine allowing for measurement of the bio-accessibility of ingested QU. Stability comparison of the empty liposomal particles, SQ-LPs and SQ-βS-ST-LPs particles was carried out to determine the most appropriate form of QU-loaded ML-based liposomal formulation. Different formulations were observed to possess different amounts of bio-accessible QU, indicating that membrane additives had profound effect on micellization of QU during Gastro-Intestinal Tract (GIT). Bivariate correlation analysis indicated that the %bio-accessibility and %EE of QU were strongly linearly correlated (R2 = 0.989), suggesting that QU bio-accessibility depended strongly on the retaining of QU in the ML bilayer, and entrapment capacity of the system. Our results paint a consistent picture in which the vesicle integrity, membrane fluidity and membrane-stabilizing function varied upon changing the membrane lipid composition in the ML-based-liposomes.

Assessing the chargeability and separability of oat groat particles through sieving combined with triboelectrification-based approach

• Oat groats were sieved at six different aperture sizes to produce twelve fractions. • Sieved fractions were analyzed for protein, particle size and tribo-charge behavior. • Particle diameters and protein content of sieved fractions were linearly correlated. • Sieved bran fractions were rich in protein and acquired high charges at laminar flow. • Sieved starchy fractions were enriched in protein by tribo-electrostatic separation. The possibility of fractionation of dehulled oat groat particles was assessed through combined sieving and tribo-electrostatic separation approach. Through this process, oat groats were initially sieved at six different aperture sizes of 53 to 425 μm, resulting in the production of twelve different fractions including six starch-rich fractions as well as six bran-rich fractions among which the bran-rich fractions had significantly higher protein concentration (15.5–19.6%) compared to the starch-rich fractions (9.7–14.0%). A linear relationship (R 2 = 0.9554) was found between protein content and mean particle diameters (D 50 ) of all sieved fractions. The tribo-charging behavior of all sieved fractions was assessed as a function of particle size and protein content. Bran-rich particles despite their large particle sizes were acquired higher charge-to-mass (nC/g) ratios compared to starch-rich fractions at the laminar air flow rate (Re = 2091) in contact with polytetrafluoroethylene (PTFE) tribo-charging tube. To exclusively evaluate the tribo-charging behavior of the fractions as a function of protein content, the specific charge (nC/g) values were recalculated to charge density (nC/m 2 ) values and a three-stage incremental trend was observed between charge density and protein content of the fractions at the laminar air flow rate. Starch-rich fractions exhibited totally different tribo-charging behavior at the turbulent (Re = 4182) air flow rate due to the large surface-to-volume ratio of their fine small particles that resulted in enhanced particle–wall collisions and eventually acquisition of higher specific charge values compared to their equivalent sieved bran-rich fractions. The starch-rich fraction sieved at aperture size of 106 μm with protein content of 10.1% was further fractionated through single- and multi-stage tribo-electrostatic separation processes where its protein content was sharply enhanced by ~80% equivalent to over 55% protein separation efficiency.

SHORT NOTES: APPLICATION OF MINERAL FILLER IN MEDIUM DENSITY FIBERBOARD (MDF) AND ITS EFFECT ON MATERIAL PROPERTIES AS A FUNCTION OF PARTICLE SIZE

The addition of inorganic filler material in medium density fiberboard (MDF) and the effect on material properties as a function of particle size was examined. Medium density fiberboard was manufactured in a laboratory scale environment to a target raw densityof 750 kgm-3. Wood fibers were replaced by using calcium carbonate at 3 and 10 wt.% using fillers with weighted median particle sizes of d50= 2.0 μm and d50= 30 μm, respectively. Urea formaldehyde resin was used as binder in all MDF. The influence of filler addition on the modulus of elasticity, bending and tensile strength, dimensional stability and liquid permeability was investigated. The results demonstrate the effect of filler content and its dependence on particle size. The addition of filler with d50= 30 μm does not have any influence on material properties up to a filler content of 10 wt.%. Using the finer filler with d50= 2.0 μm at 10 wt.% filler, the quantity significantly increases the water adsorption and swelling behavior and reduces the strength properties of the MDF.

A Scaling Approach for Retention Properties of Crystalline Rock: Case Study of the In‐Situ Long‐Term Sorption and Diffusion Experiment (LTDE‐SD) at the Äspö Hard Rock Laboratory in Sweden

AbstractThe in‐situ long‐term sorption and diffusion (LTDE‐SD) experiment performed at the Äspö Hard Rock Laboratory in Sweden aims at increasing knowledge of sorption and diffusion processes of radionuclides in natural fractures and granodiorite matrix under in‐situ conditions. This paper presents a comprehensive modeling exercise focusing on the scaling approach for sorption and diffusion parameters from laboratory to in‐situ conditions using the LTDE‐SD data set for six representative radionuclides. The near‐surface heterogeneities at both the fracture surface and rock matrix were evaluated by the conceptual model with high porosity, diffusivity, and sorption capacity, as well as their gradual changes at the near‐surface zones. The modeling results for non‐sorbing Cl‐36 and weak‐sorbing Na‐22 validated the model concept and parameter estimation of porosity and diffusivity by considering a 5‐mm‐thick disturbed zone with gradual parameter changes and an undisturbed matrix characterized by constant parameters. The effective diffusivities (De) of these cationic and anionic tracers showed typical cation excess and anion exclusion effects; however, the cation excess diffusion was more pronounced due to the heterogeneous pore networks in this granodiorite. The modeling results for high‐sorbing tracers (Cs‐137, Ra‐226, Ni‐63, and Np‐237) with different sorption mechanisms validated the scaling approaches of distribution coefficients (Kd) as a function of particle size and their relation to near‐surface disturbances. Sorption dependence on particle size could be understood in relation to different sorption mechanisms and mineralogical features. This modeling exercise provided key recommendations toward better scaling approaches for estimating reliable De and Kd parameters under in‐situ conditions.

Magnetic Fluid Assisted Electro-Leaching for Metal Recovery

In current research, micro and nanoparticulate electrode materials have taken their place because they offer a large internal surface area with respect to the macroscopic dimensions of such electrodes [1]. The nano-impact method is a powerful tool that enables the characterization of individual particulate nano-objects in solution and study of their reactivity [2]. A three electrodes setup system working as a standard electrochemical cell is typically used. Magnetite (Fe3O4) nanoparticles with the strongest saturation magnetization of all naturally occurring iron oxides, combined with properties such as low toxicity, good biocompatibility, high stability, and low production costs, have attracted a lot of interest [3]. There is also substantial interest in their use as magnetic fluids, in data storage, in catalysis, and as electrode materials.In this work, magnetite micro and nanoparticles have been synthetized by chemical precipitation method in presence of surfactants or functional organic polymer. The effects of various parameters such as contact time, dosage of magnetite nanoparticles and the amount of functional groups on the adsorption capacity and efficiency of the treatment in the adsorption of copper and lithium are investigated. The use of surfactants to stabilize these synthesized nanoparticles is crucial, as Fe3O4 nanoparticles have high surface energies and tend to aggregate. Magnetic fluids constituted by dispersed functionalized magnetite particles are used as particulate electrode in different fluids and characterized into a three electrodes cell in order to evaluate their electrochemical behavior. A deeper understanding of the particulate electrode has been performed in situ on supported particles through electrochemical AFM/STM measurements, highlighting the behavior of the single aggregate. Together with the charge transfer characterization as a function of particles size and concentration, functionalization and fluid composition, practical applications of the particulate electrodes will be presented. Specifically, the use of particulate electrodes in the electrochemical metal recovery, showing the ions adsorption properties of magnetite particles as a function of surface functionalization and their electrochemical reduction at the magnetic fluid/current collector interphase will be discussed for specific systems, e.g. copper and lithium.1. V. Noack, H. Weller, A. Eychmu1ller, J. Phys. Chem. B, 106 (2002) 8514-85232. S.V Sokolov et al., Phys.Chem.Chem.Phys., 19 (2017) 283. K. Murugappan, ChemElectroChem, 1 (2014) 1211 – 1218

CFD study of drag and lift coefficients of non-spherical particles

The prediction of correct drag and lift forces acting on immersed bodies is vital for optimized efficiency and industrial economics. Particulate suspensions involving non-spherical particles are extensively used in the chemical and medical industry. In recent years, the hydrodynamics of non-spherical particles have attracted much attention. The hydrodynamic forces acting on these particles are the function of particle size, shape, orientation, and the physical properties of fluid. In the current research, the drag and lift coefficient of non-spherical particles of disc and prolate shapes at different inclination angles and Reynolds number (Re) is calculated using the simplified Eulerian approach of computational fluid dynamics (CFD). The method adopted for simulation is first validated for a simple case of sphere. The effect of orientation and Re on drag and lift coefficient (CD and CL, respectively) is studied and compared with the available data. It is found that CD and CL increase as the angle of inclination increases, but decrease with Re. CD and CL are smaller for prolate at given Re and orientation than for the case of disc. The effects of finite size geometry cause some deviation in results from the literature. The results obtained with this simple and less computationally intensive method agree well with highly resolved numerical simulations with minor deviations.

Melting and phase diagram of Au-Cu alloy at nanoscale

The Au-Cu nanoalloys (NPs) were produced by NaBH4 co-reduction from the mixture precursor solution of component Au and Cu, under the protection of sodium citrate stabilizer. The Au-Cu NPs encapsulated in SiO2, Au5Cu5@SiO2 NPs, were then synthesized by the Stöber method based on the obtained Au-Cu NPs. The microstructure and particle sizes were characterized by TEM observation. The phase transition temperature of Au-Cu@SiO2 was determined by DSC measurement. The surface tension, surface segregation and surface energy of Au-Cu NPs as a function of particle size and temperature were calculated by the theoretical model based on the thermodynamic properties of pure component of Au and Cu NPs, respectively. The thermodynamic parameters of Au-Cu system at various nanoscales were optimized on the basis of experimental and theoretical results in this work and previous results in literature. Based on the obtained the thermodynamic data set, the nano phase diagrams of the Au-Cu system at nanoscale were calculated, and the thermodynamic properties of Au-Cu nanometer system were obtained. The results show that the calculated results agree well with experimental work.

Towards understanding particle rigid-body motion during solid-state sintering

A quantitative understanding of particle rigid body (RB) motion that inherently accompanies grain boundary (GB) diffusion is highly desirable to understand and control the dynamic interplay between coarsening and densification during solid state sintering. By computer simulation using a multi-phase-field approach, we analyze systematically the roles played by each of these processes at different stages of the shrinkage of the internal pore in a three-particle green body as a function of particle size as well as thermodynamic and kinetic factors of interfaces. We demonstrate that particle RB translation promotes both neck growth, and pore rounding and shrinkage. Moreover, the forces acting at GBs and pulling neighboring particles towards one another dynamically evolve as particles fuse. In contrast, particle RB rotation has no contribution to pore shrinkage. The translational force acting on an individual particle varies with not only its size, but also the number and sizes of its neighboring particles.

An expression for the angle of repose of dry cohesive granular materials on Earth and in planetary environments

The angle of repose-i.e., the angle [Formula: see text] between the sloping side of a heap of particles and the horizontal-provides one of the most important observables characterizing the packing and flowability of a granular material. However, this angle is determined by still poorly understood particle-scale processes, as the interactions between particles in the heap cause resistance to roll and slide under the action of gravity. A theoretical expression that predicts [Formula: see text] as a function of particle size and gravity would have impact in the engineering, environmental, and planetary sciences. Here we present such an expression, which we have derived from particle-based numerical simulations that account for both sliding and rolling resistance, as well as for nonbonded attractive particle-particle interactions (van der Waals). Our expression is simple and reproduces the angle of repose of experimental conical heaps as a function of particle size, as well as [Formula: see text] obtained from our simulations with gravity from 0.06 to 100 times that of Earth. Furthermore, we find that heaps undergo a transition from conical to irregular shape when the cohesive to gravitational force ratio exceeds a critical value, thus providing a proxy for particle-scale interactions from heap morphology.

Mechanical characteristics of magnetite as a function of particle size during column-based magnetic separation

ABSTRACT Column-based magnetic separation can concentrate magnetite while preventing magnetic particle agglomeration. Changes in the force characteristics during this process greatly affect the separation of different magnetite components. Here, the mechanical characteristics of magnetite with different particle sizes during column-based magnetic separation are studied. Upon reducing the particle size (passing 74 μm) from 45% to 90%, the magnetic force () required to separate the magnetite concentrate gradually increased. The difference in the magnetic force required to capture magnetite concentrate and rich interlocking concentrate by a magnetic field decreased from 39.53% to 13.92%. The difference in the magnetic force required to capture lean interlocking concentrate and gangue minerals by a magnetic field decreased from 75.87% to 54.26%. Verification tests showed that pre-separating magnetite concentrate and gangue from individual coarse particles reduced the workload of subsequent grinding and separation, making it easier to separate magnetite from the concentrate.

Droplet and particle methods to investigate turbulent particle laden jets

The SARS-CoV-2 pandemic has heightened the interest in particle-laden turbulent jets generated by breathing, talking, coughing and sneezing, and how these can contribute to disease transmission. We present quantitative measurement methods for such flows, while exploring and offering improvements for common shortcomings. We generate jets consisting of either liquid droplets or solid particles in an isothermal, quiescent and electrically isopotential experimental chamber that was constructed to control the effects of ambient forcing on jet behavior. For liquid droplets, we find promise in surface deposition analysis based on fluorescent tracer use. For particles, we explore the performance of commercially available adhesive sampling strips and develop conductive grounded carbon tape based sampling strips. We explore ways in which the smallest of thermal gradients or electrostatic charge issues can affect particle dispersion, and suggest practical methods to address these issues. The developed methods are applied to study the simultaneous deposition of (Formula presented.) 25, 50 and 200 μm solid particles from a particle laden turbulent jet with a mean velocity of 33.2 m/s. The deposition location as a function of particle size was compared to results from a simple numerical RANS model, and illustrates ways in which imprecise initial or boundary conditions can lead to a notable deviation from experimental results. The differences in deposition pattern seen in experimental and numerical results despite a carefully controlled environment and characterized particle ejection indicate the need for a more stringent numerical model validation, especially when studying fate and transport of mid-range (neither purely aerosol or ballistic) sized particles.

Analysis of Mie resonances using the Debye series.

Scattering of light from homogeneous spherical particles can exhibit sharp resonances as functions of particle size, wavelength, or refractive index. Such resonances, usually known as morphology-dependent resonances or whispering gallery modes, have been exhaustively studied using Mie theory. This paper demonstrates that the Debye series expansion provides a succinct and easily understood representation of these resonances: For example, the Debye coefficient Rn121 determines (a) the exact conditions for resonance, (b) the number of terms required to replicate the Mie result, and (c) the Q-factor of the resonance.

Insights into vertical differences of particle number size distributions in winter in Beijing, China

Particle number size distribution (PNSD) is of importance for understanding the mechanisms of particle growth, haze formation and climate impacts. However, the measurements of PNSD aloft in megacities are very limited. Here we report the first simultaneous winter measurements of size-resolved particle number concentrations along with collocated gaseous species and aerosol composition at ground level and 260 m in Beijing. Our study showed that the vertical differences of particle number concentrations between ground level and aloft varied significantly as a function of particle size throughout the study. Further analysis illustrated the impacts of boundary dynamics and meteorological conditions on the vertical differences of PNSD. In particular, the temperature and relative humidity inversions were one of the most important factors by decoupling the boundary layer into different sources and processes. Positive matrix factorization analysis identified six sources of PNSD at both ground level and city aloft. The local source emissions dominantly contributed to Aitken-mode particles, and showed the largest vertical gradients in the city. Comparatively, the regional particles were highly correlated between ground level and city aloft, and the vertical differences were relatively stable throughout the day. Our results point towards a complex vertical evolution of PNSD due to the changes in boundary layer dynamics, meteorological conditions, sources, and processes in megacities.

CFD simulation of tailings slurry thickening in a gravity thickener

In the present study, the thickening process of tailings slurry in a gravity thickener is modelled using Computational Fluid Dynamics (CFD), with a focus on the effects of particle size and feed velocity. A Two-Fluid Model (TFM) is employed to describe the particle-fluid and particle-particle interactions while turbulence is described by the ω-based Reynolds Stress Model (RSM). The validity of the model is demonstrated by close agreement between experimental measurement and simulation predictions of total solid mass of underflow, and particle cumulative mass distribution as a function of particle size in the underflow. The feedwell performance is evaluated in terms of kinetic energy dissipation and mixing performance. Particle size has a significant influence on the distribution of solid concentration. The increase of particle size leads to a higher critical settling height. For a given underflow discharging rate, solid concentration in the underflow increases with feed velocity only in a certain range, whereas increases continuously in the overflow. Large particle size corresponds to a higher critical feed velocity. Modelling the granular flow with a wide particle size distribution in a thickener helps explore the particle dynamic behaviors, thereby improving the thickening process.

Particle size effects on dislocation density, microstructure, and phase transformation for high-entropy alloy powders

Recrystallization and phase transformation reactions are driven by energy stored in the parent phase due to previous processing history. Grain boundaries, lattice strain, and dislocation networks may affect subsequent microstructural evolution, especially during metal powder consolidation processes. In this work, AlCrFe2Ni2 eutectic high-entropy alloy powders over a wide range of size distribution were used to investigate the correlation between dislocation density and microstructure as a function of particle size. Line profile analysis of the X-ray diffraction patterns of the as-received (quenched) samples shows that the dislocation density increases linearly with decreasing particle size. Based on microstructure analysis of the as-quenched and the annealed samples, it is found that the correlation is associated with the grain boundary length which increases with decreasing particle size, revealing that the key source of dislocation density is dislocations within the grain boundaries. The grain boundary energy acts as a driving force for the metastable to stable phase transformation of AlCrFe2Ni2, showing that the phase transformation kinetics is a function of particle size. This work shows a direct experimental observation and quantitative analysis that in metallic powder systems particle size is one of the key parameters which affects the dislocation density and the phase transformation kinetics most probably due to the different cooling rates achieved during powder production.

Mineralogical and chemical characterization of CDW as function of particle size and thermal treatments for potential recycling

Construction and Demolition Waste (CDW) originating from the rubble produced by the 2016 seismic events in the Marche Region (Central Italy) has been studied, focusing on its mineralogical and chemical characteristics, to investigate its recycling potentials as a component for eco-sustainable building material or in the glass industry. The aim was to obtain a full characterization of the behaviour of this material at high T in order to determine the most advantageous conditions for vitrification, considered as an effective process for volume reduction as well as for immobilization of potentially hazardous elements. Vitrification experiments, carried out with thermal treatments as function of temperature/duration/particle size and aimed at amorphization, were carried out under atmospheric conditions, at different temperatures (1000-1250°C) and durations (2-8 hours). The study demonstrated that mineralogical composition remains homogeneous for grainsize <4 mm, thus suggesting that no sieving is necessary for recycling of the fine fractions, which are the most difficult to treat. Vitrification, although not achieved for the CDW sample up to 1250°C, due to high-Ca and low-Si contents, demonstrated that this CDW can produce an interesting refractory material and a porous/insulating material. However, experiments showed that full vitrification can be easily achieved by mixing urban waste glass and CDW, suggesting applications in the glass industry. Based on the chemical and mineralogical features of the products, other significant upgrading alternatives of recycling the CDW in different fields of applications are highlighted.

Shape dependence of snow crystal fall speed

Abstract. Improved snowfall predictions require accurate knowledge of the properties of ice crystals and snow particles, such as their size, cross-sectional area, shape, and fall speed. The fall speed of ice particles is a critical parameter for the representation of ice clouds and snow in atmospheric numerical models, as it determines the rate of removal of ice from the modelled clouds. Fall speed is also required for snowfall predictions alongside other properties such as ice particle size, cross-sectional area, and shape. For example, shape is important as it strongly influences the scattering properties of these ice particles and thus their response to remote sensing techniques. This work analyzes fall speed as a function of particle size (maximum dimension), cross-sectional area, and shape using ground-based in situ measurements. The measurements for this study were done in Kiruna, Sweden, during the snowfall seasons of 2014 to 2019, using the ground-based in situ instrument Dual Ice Crystal Imager (D-ICI). The resulting data consist of high-resolution images of falling hydrometeors from two viewing geometries that are used to determine particle size (maximum dimension), cross-sectional area, area ratio, orientation, and the fall speed of individual particles. The selected dataset covers sizes from about 0.06 to 3.2 mm and fall speeds from 0.06 to 1.6 m s−1. Relationships between particle size, cross-sectional area, and fall speed are studied for different shapes. The data show in general low correlations to fitted fall speed relationships due to large spread observed in fall speed. After binning the data according to size or cross-sectional area, correlations improve, and we can report reliable parameterizations of fall speed vs. particle size or cross-sectional area for part of the shapes. For most of these shapes, the fall speed is better correlated with cross-sectional area than with particle size. The effects of orientation and area ratio on the fall speed are also studied, and measurements show that vertically oriented particles fall faster on average. However, most particles for which orientation can be defined fall horizontally.

Agglomeration of particles by a converging ultrasound field and their quantitative assessments

The acoustic radiation force resulting from acoustic waves have been extensively studied for the contact-free generation of organized patterning arrays. The precise arrangement of microscopic objects clustered at the pressure nodes is critical to the development of functional structures and patterned surfaces. However, the size of the clusters is restricted by the saturation limit of the acoustic nodes. Here, we present a bulk acoustic wave (BAW) platform, which employs a two-dimensional acoustic wave to propel particles of various sizes. Experimentally, when particles are large, significant acoustic energy is scattered and partly absorbed by the matched layers in front of the sensors. The acoustic radiation force from a convergent acoustic pressure field agglomerates the large polystyrene (PS) particles towards the central region instead of the pressure nodes. The parametric analysis has been performed to assess the transition in the particles from clustering at the organized nodal arrays to agglomerating in the central region, which is a function of particle size, particle concentration, and load voltage. Statistically, the particles can agglomerate with a cluster ratio greater than 70%, and this ratio can be improved by increasing the load power/voltage supplied to the transducers. With its ability to perform biocompatible, label-free, and contact-free self-assembly, this concept offers a new possibility in the fabrication of colloidal layers, the recreation of tissue microstructure, the development of organoid spheroid cultures, the migration of microorganisms, and the assembly of bioprinting materials.