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Surface wettability is a critical factor in multi-phase flow within porous media, a processes essential in various applications e.g. in the energy sector. Traditional methods for assessing wettability of porous media by contact angle measurements, such as sessile droplet and micro-CT techniques, are limited by interface pinning, sample size or resolution impacting precision and accuracy. We hypothesized that using smaller and unconstrained probes, specifically gas molecules, to retrieve interactions along a representative sample size via inverse gas chromatography (IGC) could provide a more accurate determination of contact angles. We propose a procedure to relate IGC results with macro-scale wettability descriptions, such as the Young equation. To test the effectiveness of IGC method, glass bead samples with varying wettability, modified through a silanization process, were prepared. Contact angles for a distilled water-air-sample system were measured using the sessile droplet method and micro-CT for comparative analysis. IGC was employed to determine the surface energy components of these samples, which were then used in the extended Young-Dupré equation to calculate the contact angles. The contact angle ranges determined by IGC and micro-CT for untreated glass beads, the most hydrophilic samples, showed great alignment. This consistency is attributed to the chemical amorphous nature of the untreated beads reflected in the assumption that dispersive and specific energetic components of surface sites are uncorrelated, on which the proposed analysis is based. For treated samples, where the silanization process creates correlations between surface energetic components, the alignment between IGC and micro-CT results was less precise. This study successfully demonstrated that IGC, a molecular-scale probe-based technique, can effectively determine the contact angle range, a macroscopic property, for amorphous samples. Future work should incorporate correlations between energetic components of surface detected by IGC to extend this method's applicability to a wider material range.   • Novel IGC-based method introduced for determining contact angle ranges in porous media. • Validated IGC method by comparing contact angles with micro-CT and sessile droplet tests. • Assessed IGC's applicability across different wettability levels using silanized glass beads. • Remarkable alignment with micro-CT and sessile droplet data for unmodified glass beads. • IGC effectively detected wettability changes in silanized glass beads. [ABSTRACT FROM AUTHOR]

Using glass beads as an ideal material analogous to soil particles makes it feasible to explore the effects of particle interactions on the mechanical behavior of the material. In this study, 2 mm high-precision spherical glass beads were selected as the raw material, and three test samples with varying surface roughness were produced using sandblasting technology. After quantifying the surface roughness of the particles, samples were prepared, and a series of laboratory triaxial consolidation drainage tests were conducted to investigate the shear behavior of particle materials with varying roughness levels. This investigation explores the effects of variations in particle surface roughness on the stress–strain characteristics, shear strength, critical state, and stick–slip behavior of triaxial samples. The experimental results indicate that an increase in particle surface roughness significantly raises the peak deviatoric stress, and the stress–strain curves predominantly exhibit strain softening behavior. Additionally, the slope of the critical state line increases, and the stick–slip behavior becomes less pronounced. The variation trend of the roughness index is similar to peak friction angle (φmax), peak deviatoric stress growth rate, slope (k) of the critical state line, and the maximum deviatoric stress drop (Δqmax) during stick–slip process. [ABSTRACT FROM AUTHOR]

In the mixing zone, where submarine groundwater carrying ferrous iron [Fe(II)] meets seawater with dissolved oxygen (DO), the oxidative precipitation of Fe(II) occurs at the pore scale (nm~μm), and the resulting Fe precipitation significantly influences the seepage properties at the Darcy scale (cm~m). Previous studies have presented a challenge in upscaling fluid dynamics from a small scale to a large scale, thereby constraining our understanding of the spatiotemporal variations in flow paths as porous media evolve. To address this limitation, this study simulated subsurface mixing by injecting Fe(II)-rich freshwater into a DO-rich saltwater flow within a custom-designed syringe packed with glass beads. Micro-computed tomography imaging at the representative elementary volume scale was utilized to track the development of Fe precipitates over time and space. Experimental observations revealed three distinct stages of Fe hydroxides and their effects on the flow dynamics. Initially, hydrous Fe precipitates were characterized by a low density and exhibited mobility, allowing temporarily clogged pathways to intermittently reopen. As precipitation progressed, the Fe precipitates accumulated, forming interparticle bonding structures that redirected the flow to bypass clogged pores and facilitated precipitate flushing near the syringe wall. In the final stage, a notable reduction in the macroscopic capillary number from 3.0 to 0.05 indicated a transition from a viscous- to capillary-dominated flow, which led to the construction of ramified, tortuous flow channels. This study highlights the critical role of high-resolution imaging techniques in bridging the gap between pore-scale and continuum-scale analyses of multiphase flows in hydrogeochemical processes, offering valuable insights into the complex groundwater–seawater mixing. [ABSTRACT FROM AUTHOR]

This research investigates the influence of various concentrations of BaTiO3 nanofluid on adsorption energy and improved oil recovery. BaTiO3 nanoparticles were successfully synthesized using a Sol-gel approach at temperatures of 400 °C, 500 °C, 800 °C, and 1000 °C and characterized for their structural and morphological properties and interfacial tension (IFT)/Wettability measurement. The study focuses on using ferroelectric nanofluid in combination with an electromagnetic field to enhance oil recovery mechanisms. Three concentrations of BaTiO3 nanofluid were prepared, and their effects on pressure and recovery factors were examined. The results demonstrate that BaTiO3 nanofluids increase the reservoir fluid's ionic conductivity, leading to environmental polarization. Applying BaTiO3 nanofluid on glass bead samples resulted in a significant 42.15% increase in the recovery factor at a 0.3% concentration in various measurements, including interfacial tension, core-flooding, and wettability. The nanofluid caused a reduction in interfacial tension and a shift in wettability from oil-wet to water-wet. The higher adsorption energy of the nanofluid corresponded to more significant oil recovery. The optimal concentration for maximum adsorption energy (−2.566331 × 104) and oil recovery (22.5%) was 0.3wt%. At 0.1% concentration, the IFT value was 0.023 mN/m, at 0.3% concentration the IFT was 0.017 mN/m and at 0.5% concentration IFT value was 0.032 mN/m. The contact angle of the brine with the oil was 89.39% compared to the contact angle of 0.1%, 0.3%, and 0.5% which were 64.25%, 10.57%, and 44.63%, respectively. It was revealed from the result that 0.3% of nanofluid decreased the contact angle from 89.39% to 10.57 at a 0.3% concentration of BaTiO3 nanofluid. This shows that the wettability of the rock surface changed from oil-wet to water-wet with the novel application of BaTiO3 nanoparticles. This improvement in recovery can be attributed to the modification of wettability and reduction of interfacial tension. [ABSTRACT FROM AUTHOR]

In this study, in a three-phase reactor with a rectangular cross-section, the effects of liquid circulation rates and solid particle concentration on gas holdup and bubble size distribution (BSD) were investigated. Air, water, and glass beads were used as the gas, liquid, and solid phases, respectively. Different liquid circulation velocities and different solid loads were applied. The results demonstrate that increasing solid content from 0% to 6% can decrease gas holdup by 50% (due to increased slurry phase viscosity and promotion of bubble coalescence). Also, increasing the liquid circulation rate showed a weak effect on gas holdup, although a slight incremental effect was observed due to the promotion of bubble breakup and the extension of bubble residence time. The gas holdup in counter-current slurry bubble columns (CCSBCs) was predicted using a novel correlation that took into account the combined effects of solid concentration and liquid circulation rate. These findings are crucial for the design and optimization of the three-phase reactors used in industries such as mining and wastewater treatment. [ABSTRACT FROM AUTHOR]

This study emphasizes the significance of understanding groundwater flow behavior for effective contaminant transport and heat storage. Aquifers, with their irregular shapes and variable permeability, exhibit anisotropic flow resistances that affect mass and heat transfer, posing challenges for modeling. The dual-porosity model is used as a numerical approach to calculate macroscopic heat transfer without explicitly resolving the structure. By solving equations for mobile and immobile phases and coupling relevant equations for heat conservation, this model was applied to transient numerical experiments simulating heat transfer and storage in a desktop model filled with glass beads. Results indicate alignment with experimental and numerical models resolving porous structures on the microstructure scale. This methodology offers a comprehensive digital toolbox for solving large-scale heat storage problems in aquifers, contributing to digital and sustainability transformations with reasonable computational demands. [ABSTRACT FROM AUTHOR]

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Noise in the immunohematological investigations can be described as a false reactivity of red blood cells (RBCs) in serologic testing that is not related to the interaction of RBC antigens and antibodies that the test system is intended to detect. These false-positive reactions can cause confusion during the cross-matching and RBC antibody screening and may result in delays in patient transfusion. Although these antibodies are predominantly clinically insignificant, proper laboratory work-up is indicated to avoid misidentification of a clinically significant antibody as a noise. In this report, we describe the three rare cases where the reactivity was found against the ingredients of the column matrix (glass beads). It is imperative that such reactivity is recognized and resolved during the investigation of blood group discrepancies, positive RBC antibody screens and in cases of positive cross-matches.

[Display omitted] • Mesoporous NiFe 2 O 4 from sludge boosted CO 2 plasma-cracking efficiency. • SiO 2 glass beads promoted CO 2 conversion by micro-reactor effects. • Plasma and catalysts synergistically lowered CO 2 -cracking barriers. • Electron recombination on the NiFe 2 O 4 surface accelerated CO 2 decomposition. An innovative, environment-friendly, and efficient method was proposed for the synergistic low-temperature plasma conversion of CO 2 by using nickel ferrite (NiFe 2 O 4) catalyst. NiFe 2 O 4 , characterised by a mesoporous spinel structure, was successfully synthesised from electroplating sludge by a single-step heat treatment. The catalyst was uniformly distributed with SiO 2 glass beads throughout the plasma discharge area, enabling an efficient transition from single filament to filament-surface coupled discharge. The outcomes were a 39.02 % increase in discharge charge and a 15 % increase in output power compared with plasma-only situation. CO 2 -conversion optimisation tests showed the formation of a 'microreaction zone' enhanced the development of gas vortices and turbulence, promoting the CO 2 -conversion ratio, CO generation ratio, and energy efficiency to 20.64 %, 15.74 %, and 1.864 %, respectively, under the NiFe 2 O 4 catalyst-facilitated low-temperature plasma conditions. The conversion route involved generating excited-state CO, O 2 , and electrons through plasma ionisation of CO 2 , alongside the creation of oxygen vacancies (V o). These vacancies regenerated by consuming lattice oxygen (O2−), facilitating CO 2 convert to CO and O 2 by electrons. Furthermore, the catalysts offered sites for adsorbing reaction intermediates, which further facilitated CO 2 dissociation and product formation. The Fe and Ni ions in the NiFe 2 O 4 catalyst reacted by redox to produce O2− and V o and maintain charge equilibrium. This study demonstrated that the NiFe 2 O 4 catalyst and synergistic plasma effectively converted CO 2 whilst reducing the reaction's energy barrier, thereby providing theoretical support for improved CO 2 utilisation as a resource. [ABSTRACT FROM AUTHOR]

Surfactant plays a crucial role in the chemical enhanced oil recovery (cEOR) process, and in‐situ emulsification is regarded as one of the mechanisms for surfactant flooding. However, no direct evidences are available so far to show how emulsions are generated in porous media, and how emulsification is essential for cEOR. To address these issues, binary mixtures of several currently‐used sulfonate surfactants, SH5, SH6, and SHZ, were formulated with connate brine to displace crude oil in both 2D microfluidic chips and 3D glass beads porous media, as well as artificial cores. It was found that both “oil‐in‐water” (O/W) and “water‐in‐oil” (W/O) macroemulsions can be formed in‐situ inside the porous media, and they improve oil recovery mainly through breaking residual oil into small drops and improving mobility ratio, which can significantly reduce the residual oil saturation by up to 12.8% in 2D microchips. The in‐situ emulsification in 3D glass beads medium can get oil recovery factor up to 15% over water flooding. In‐situ formulation of microemulsion was also observed in microfluidic flow tests. Part of the oil phase is emulsified into microemulsions that are present in the middle phase, further mobilizing the oil trapped downstream, lowering residual oil saturation from 54.8% to 11.3% in 2D microchips, and enhancing oil recovery factor up to 25% in core flooding test. These findings advance insightful understanding of in‐situ emulsification during surfactant flooding process under simulated oil reservoir condition, offering real‐time evidence of how both macro‐ and micro‐emulsions formation help for cEOR. [ABSTRACT FROM AUTHOR]

Micro-computed tomography (CT) of ancient Chinese glass dragonfly eye beads has enabled detailed exploration of their internal structures, contributing to our understanding of their manufacture. Segmentation of these CT images is essential but challenging due to variation in grayscale values and the presence of bubbles. This study introduces a U-Net-based model called EBV-SegNet, which enables efficient and accurate segmentation and visualization of these beads. We developed, trained, and tested the model using a dataset comprising four typical Shampula dragonfly eye beads, and the results demonstrated high-precision segmentation and precise delineation of the beads' complex structures. These segmented data were further analyzed using the Visualization Toolkit for advanced volume rendering and reconstruction. Our application of EBV-SegNet to Shampula beads suggests the likelihood of two distinct manufacturing techniques, underscoring the potential of the model for enhancing the analysis of cultural artifacts using three-dimensional visualization and deep learning. [ABSTRACT FROM AUTHOR]

Taking the fluidized pre-reduction process of iron ore powder bubbling fluidized bed as the background, for the problem of non-uniform structure in the bed of gas-solid fluidization process, the non-uniform fluidization characteristics of bicomponent particles are investigated in a cold two-dimensional bubbling fluidized bed by using a combination of physical experiments and mathematical simulations. Fluidization experiments were carried out under typical working conditions by using glass beads to study the effects of apparent gas velocity, mass ratio, and other factors on the non-uniform structure in the bed. Through the experimental observation of the bubble behavior, the effect of the cyclic change in bubble formation, rise and growth to rupture on the bed uniformity were analyzed. The experiments showed that the fluidized bed of two-component particles would be stratified, and the non-uniformity was strong in the upper part and weak in the lower part, and the apparent gas velocity and particle size were the main influencing factors. Based on the Euler-Lagrange reference frame modeling, the fluidization process of the two-dimensional bubble bed was simulated by the CFD-DEM method. The simulations of typical experimental conditions were carried out to further analyze the velocity distribution and the volume ratio of each phase in the bed from the gas-solid interaction level, revealing that the velocity distribution in the upper part of the bed is not uniform, and the gas flow is strongly perturbed, with intense bubble aggregation. The results reveal the reasons for the non-uniform phenomenon of gas-solid fluidization, which can provide a theoretical basis for the regulation of the non-uniform structure of the fluidization process. [ABSTRACT FROM AUTHOR]

Ultrasound imaging velocimetry (UIV) is a maturing technique for measuring the dispersed phase in two-phase flows. It enables measurements of dense suspensions when optical methods fail. This study explores UIV's applicability to measure the flow field in a swirling flow reactor (SFR) for solid–liquid mixing of dense suspensions. Despite UIV's historical focus on unidirectional flows like arteries and axisymmetric pipes, this research demonstrates its adaptation to an inherently complex 3D flow field, i.e., a swirling sudden expansion flow in an SFR. Using high-speed plane-wave imaging and correlation averaging techniques, satisfactory velocity profiles are achieved while preserving sufficient temporal information. Firstly, the applicability of UIV in this specific setup is demonstrated by comparing UIV with stereoscopic particle image velocimetry measurements of a single-phase flow in the SFR, both indicating a Coandă jet flow (CoJF). Secondly, several bulk velocities and volume concentrations (up to 50 vol%) are measured with UIV for a suspension of water and 2.3-mm glass beads. A transducer is installed in two orientations and captures all three velocity components when combining the two datasets. A timestep optimization process is implemented to avoid the need for manual finetuning of the acquisition frequency. A time-domain spectral analysis on the dispersed phase velocity fields in the SFR reveals dominant frequencies between 1.21 and 2.42 Hz, similar to those found in single-phase flow. The general flow structure of the dispersed phase in suspension is very similar to the latter; however, the addition of particles confines the central recirculation zone (CRZ) to the center. Finally, the implementation of swirl to keep solid–liquid mixtures in suspension in the SFR is experimentally confirmed by this study. Quantitative UIV measurements confirm favorable flow structures for mixing, specifically a CoJF that avoids sedimentation. The concentration of solids in an SFR can even be increased up to 50 vol% while still maintaining a uniform suspension. [ABSTRACT FROM AUTHOR]

This study presents technologies of the triple hybrid landing gear for the OMOTENASHI(Outstanding Moon exploration Technologies demonstrated by Nano Semi-Hard Impactor) spacecraft, which consists of an airbag, a crushable material as a shock absorber, and an impact resistance structure. The inflated airbag has capability to possibly mitigate impact acceleration at the instant of landing and submergence into regolith that covers a planetary surface. The crushable material with lattice structures, manufactured by a metal 3D printer, serves a dual purpose: it dissipates kinetic energy and controls the impact acceleration at landing by compressing itself within a designed deceleration distance. Further, in the impact resistance structure, the protective object is filled with resin and hollow glass beads, and the impact resistance is improved while the weight reduction is maintained. This paper provides the technical details such as the required specification, verification test results, and assembly result of the surface probe as the smallest lander of the OMOTENASHI spacecraft. • The triple hybrid landing gear appeared for the world's smallest lunar lander. • Shock absorber, airbag, and shock-resistant structure were complementarily combined. • The shock absorber with excellent mounting capability was produced by a 3D printer. • The airbag shape was designed with the Terra-mechanics theory. • Development tests suitable for small landers were demonstrated. [ABSTRACT FROM AUTHOR]

A composite of polyethylene terephthalate (PET) and hollow glass beads (HGB) with two different HGB sizes was prepared and investigated rheologically. When the HGB content reaches approximately 30 wt%, the PET/HGB composite changes from a Newtonian fluid to a pseudoplastic one within the measured frequency range. If the HGB content is below the critical value, the viscosity of the composite may be lower than that of the neat PET melt. This is because scrolling or sliding of the HGB in the PET melt increases the apparent shear rate and reduces the torque measured by the rheometer rotor. Meanwhile, the size of the HGB affects the viscosity of the composite. The 40 μm HGB has a more pronounced effect, resulting in higher viscosity than 50 μm HGB. Furthermore, the composite containing 40 μm HGB has a lower density than the one containing 50 μm HGB. This is because the 40 μm HGB has a lower breaking rate and higher volume fraction compared to the 50 μm HGB at the same mass fraction. The peak relaxation time of the PET/HGB composite increases with the HGB content, and higher temperatures correspond to shorter relaxation times. DSC analysis showed that the addition of HGB filler decreased the melting temperature and increased the crystallization temperature of the PET material. Since the PET/HGB composite has a longer relaxation time than pure PET, the corresponding aggregates made of PET chains and HGBs are expected to have larger characteristic sizes compared to PET and HGB. These sizes can be determined approximately using a grid drawing method. The coupling agent CS‐101 enhances the bonding between PET and HGB. This is evidenced by comparing the viscosity curves of the composite with and without the coupling agent. Highlights: The polyethylene terephthalate (PET)/hollow glass beads (HGB) composites with low levels of HGB might exhibit unusual viscosity.Abnormal viscosity in molten PET occurs due to the rolling or sliding of HGB.The composites with high HGB levels may exhibit a solid‐like modulus plateau.The proposed aggregate consists of PET, HGB, and broken glass shards. [ABSTRACT FROM AUTHOR]

Optical micromotors are powerful tools for trapping and rotating microparticles in various fields of bio-photonics. Conventionally, optical micromotors are built using bulk optics, such as microscope objectives and SLMs. However, optical fibers provide an attractive alternative, offering a flexible photon platform for optical micromotor applications. In this paper, we present an optical micromotor designed for 3D manipulation and rotation based on a single fiber optical vortex tweezer. A tightly focused vortex beam is excited by preparing a spiral zone plate with an ultrahigh numerical aperture of up to 0.9 at the end facet of a functionalized fiber. The focused vortex beam can optically manipulate and rotate a red blood cell in 3D space far from the fiber end facet. The trapping stiffness in parallel and perpendicular orientations to the fiber axis are measured by stably trapping a standard 3-µm silica bead. The rotational performance is analyzed by rotating a trimer composed of silica beads on a glass slide, demonstrating that the rotational frequency increases with rising optical power and the rotational direction is opposite to the topological charge of the spiral zone plate. The proposed fiber micromotor with its flexible manipulation of microparticle rotation circumvents the need for the precise relative position control of multiple fiber combinations and the use of specialized fibers. The innovations hold promising potential for applications in microfluidic pumping, biopsy, micromanipulation, and other fields. [ABSTRACT FROM AUTHOR]

Glass beads laid on the road, mainly used for better visibility, can contribute to harmful anthropogenic waste to the marine environment, and it is a prerequisite to distinguish the chemical properties associated with it. This is the first systematic approach and evaluation of the toxic and non-toxic characteristics of the glass beads from the Indian coastal region (Goa state), which originated from the wearing of road paint over a period. Glass beads ranging from a few hundred to ~ 1000 µm were found on various beaches far from the roadside throughout the coastal state. Examination of these glass beads revealed the possible contribution of toxic elements such as arsenic, lead, cadmium, chromium, and barium beyond the global regulatory limit. Mercury and other analyzed elements are within acceptable limits. However, a quantitative assessment of their environmental impact indicates that glass beads can impact the marine ecosystem and increase the background level of environmental pollutants. [ABSTRACT FROM AUTHOR]

This study presents the impact of the size and shape of particles in laundry wastewater on the clogging process of a porous material. Clogging can be defined as a mechanical limitation of flow through porous media. The process of mechanical clogging was investigated in this study. The research was conducted in laboratory conditions in a filter column filled with glass beads whose diameter corresponded to coarse sand. The results reveal the influence of graywater quality on filter hydraulic conductivity and bed clogging, showing the impact of fiber particles in wastewater (sewage from home laundry) on the clogging process in soil. The results confirm that fiber particles significantly reduce filter permeability, particularly due to the formation of a filter cake. As analyzed in this paper, the distribution of quantitative data on particles of different sizes found in laundry wastewater indicates that they mainly accumulate in the upper layer, where particles with fiber lengths ranging from 0 to 1600 µm can be found. The average length of the fibers decreased with increasing depth. At a depth of approximately 10 cm, fibers with dimensions in the range of 0 to 100 μm were predominantly observed. [ABSTRACT FROM AUTHOR]

Non-conventional machining processes are capable of achieving higher performance compared to conventional ones due to their inherent characteristics and higher amount of parameters which can be favorably regulated. Although the correlation between the most important process parameters and process outcome has been already established for a wide range of conditions and workpiece materials, the introduction of new considerations related to the three pillars of sustainability require further investigation on new means for the enhancement of AWJ milling process. As one of the most important parameters in AWJ milling is the abrasive material, the introduction of new materials may offer considerable advantages from different perspectives. Thus, in the present work, a comprehensive investigation on the efficiency of using eco-friendly, mixed abrasives is carried out under various conditions such as different traverse feed rate, abrasive mass flow rate, water jet pressure, jet impingement angle, and mixing ratio. The feasibility of using mixed abrasives is evaluated in terms of achievable depth of penetration, kerf width, kerf taper angle as well as material removal rate (MRR), and cutting efficiency. The findings indicate that among other factors, the mixing ratio plays a noticeable role especially regarding MRR and cutting efficiency and can offer an additional effective means to achieve the desired kerf characteristics in conjunction with other significant parameters such as water jet pressure. [ABSTRACT FROM AUTHOR]

• Infiltration rates under low gravities were agreed with 1G based predictions. • The air entrapped little in fine porous media may have prevented the infiltration rate reduction. • The infiltration theory is applicable to fine uniform porous media under low gravities. The applicability of the theory of water infiltration in porous media under low gravities is controversial. We evaluated the hypothesis that infiltration under low gravities can be simulated from horizontal infiltration experiments under 1G. Parabolic flights provided low gravity conditions, assuming in the space station (µG), on the moon (0.19 G), and Mars (0.38 G). We measured infiltration rates in uniform particle-size porous media. No significant differences existed between infiltration rates under low gravities and ground-based predictions, i.e. the 1G condition. The air was entrapped little in this study, which may have prevented the infiltration rate reduction reported in previous studies. We concluded that the current infiltration theory adequately simulated water infiltration in fine uniform porous media under low gravity conditions. [ABSTRACT FROM AUTHOR]

Good visibility of lane markings is important for all road users, particularly autonomous vehicles. In general, nighttime retroreflectivity is one of the most challenging marking visibility characteristics for agencies to monitor and maintain, particularly in cold weather climates where agency snowplows remove retroreflective material during winter operations. Traditional surface-applied paint and glass beads typically only last one season in cold weather climates with routine snowplow activity. Recently, transportation agencies in cold weather climates have begun deploying improved recessed, durable pavement markings that can last several years and have very high retroreflective properties. Several dozen installations may occur in a state in any calendar year, presenting a challenge for states that need to program annual repainting of traditional waterborne paint lines, but not paint over the much more costly durable markings. This study reports on the utilization of mobile mapping LiDAR systems to classify and evaluate pavement markings along a 73-mile section of westbound I-74 in Indiana. LiDAR intensity data can be used to classify pavement markings as either tape or non-tape and then identify areas of tape markings that need maintenance. RGB images collected during LiDAR intensity data collection were used to validate the LiDAR classification. These techniques can be used by agencies to develop accurate pavement marking inventories to ensure that only painted lines (or segments with missing tape) are repainted during annual maintenance. Repeated tests can also track the marking intensity over time, allowing agencies to better understand material lifecycles. [ABSTRACT FROM AUTHOR]

Spherical glass beads weaken the influences of particle morphology, surface properties, and microscopic fabric on shear strength, which is significant for revealing the relationship between macroscopic particle friction mechanisms and the particle size distribution of sand. This paper explores the shear mechanical properties of glass beads with different particle size ratios under different confining pressures. It obtains the particle size ratio and fractal dimension D through an optimal mechanical response. Simultaneously, we explore the range of the fractal dimension D under well-graded conditions. The test results show that the strain-softening degree of Rs is more obvious under a highly effective confining pressure, and the strain-softening degree of Rs can reach 0.669 when the average particle size d ¯ is 0.5 mm. The changes in the normalized modulus ratio Eu/Eu50 indicate that the particle ratio and arrangement are the fundamental reasons for the different macroscopic shear behaviors of particles. The range of the peak effective internal friction angle φ is 23 °~35 °, and it first increases and then decreases with the increase in the effective confining pressure. As the average particle size increases, the peak stress ratio MFL and the peak effective internal friction angle φ first increase and then decrease, and both can be expressed using the Gaussian function. The range of the fractal dimension D for well-graded particles is 1.873 to 2.612, and the corresponding average particle size d ¯ ranges from 0.433 to 0.598. Under the optimal mechanical properties of glass beads, the particle size ratio of 0.25 mm to 0.75 mm is 23:27, and the fractal dimension D is 2.368. The study results provide a reference for exploring friction mechanics mechanisms and the optimal particle size distributions of isotropic sand. [ABSTRACT FROM AUTHOR]

Soil arching is a common phenomenon existing in the earth structures such as pile-supported embankments and buried pipes. Suffusion would be triggered in these structures during flood events after rainstorms and pipe ruptures, which poses significant threats to these infrastructures. A novel trapdoor-suffusion apparatus was developed in this study to investigate the initiation and progressive development of suffusion in infrastructures involving soil arching. A series of laboratory tests were conducted using gap-graded glass beads with an initial fine particle content of 15% by mass. Initial soil arching was established via trapdoor movement and then was subjected to a horizontal seepage flow with an increasing hydraulic gradient to induce suffusion in the arched soil. The presence of soil arching increased the susceptibility of local instability of the soil specimen within the stress reduction areas at significantly low local hydraulic gradients, due to the reduced stress restriction on fine particles. Subsequently, global suffusion was triggered at a critical hydraulic gradient much lower than the predicted value by the modified zero effective stress principle, and this critical hydraulic gradient decreased rapidly with the reduction of initial soil arching ratio (SAR). This study obtained an empirical formula in the form of power functions to characterize the variation of critical hydraulic gradient with the initial soil arching ratio. As the suffusion continued, the degradation of soil arching intensified under the low initial SAR, and became the dominant factor increasing the surface displacement of the soil. This paper reveals the increased risk of suffusion to earth structures with the presence of soil arching, and provides valuable guidance for the design and protection of earth structures against suffusion-induced challenges. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are colonized by biofilm-forming microbes. Biodegradable plastics, popular replacements for traditional plastics, still have unknown biofilm formation characteristics. We conducted a 60-day indoor experiment, where sediment was exposed to traditional MPs (polypropylene, PP), biodegradable MPs (polylactic acid, PLA), and glass beads (GLASS). The microbial communities in the MPs-biofilm were analyzed using high-throughput sequencing. Results indicated that Proteobacteria was the dominant phylum on all substrates, followed by Actinobacteria, and Firmicutes. At the genus level, the majority of microorganisms colonizing PP possessed nitrification and denitrification capabilities, while the dominant bacteria on PLA were capable of degrading lignin, cellulose and carbon metabolism. The genus Sphingomonas, a promising bacteria capable of degrading biodegradable microplastics, was particularly discovered on the PLA biofilm, meanwhile, bacterial colonization of PLA indirectly increased the potential for human transmission of pathogens. Redundancy analysis revealed that the pH and moisture significantly affected the bacterial communities. Pearson correlation heatmap indicated that the abundance of the majority of dominant bacterial genera of two MPs biofilms is negatively correlated with the physicochemical parameters of sediment (pH, moisture, TN, TP), except for salinity. The microbial communities associated with PP and PLA exhibited distinct differences caused by the combined effects of changes in physicochemical properties of sediment and different material substrates. This study provides further evidence of the significant selective features exhibited by microbial colonization on these two MPs when exposed to the same source community, offering insights into the exploration of promising bacteria for MPs degradation. [ABSTRACT FROM AUTHOR]

The study establishes two mathematical formulations to predict the pressure drop in a solid–liquid slurry flowing through a straight pipe. Employing the Eulerian–Eulerian RNG k-ε model, the computational investigation uses water as the carrier fluid and glass beads as solid particles. The analysis spans various particle sizes (d50 = 75–175 μm), volumetric concentrations (Cvf = 10–50%), and velocities (Vm = 1–5 m/s). The first model, developed using the MATLAB curve-fitting tool, is complemented by a second empirical equation derived through non-polynomial mathematical formulation. Results from both models are validated against existing experimental and computational data, demonstrating accurate predictions for d50 = 75–175 µm particles within a Reynolds number range of 20,000 ≤ Re ≤ 320,000. [ABSTRACT FROM AUTHOR]

Perfluorooctanesulfonic (PFOS) acid is a persistent anthropogenic organic fluorinated compound ubiquitous in industrial applications and is resistant to conventional wastewater treatment methods. Human exposure to PFOS can cause adverse health effects. In this study, a low‐content titanium dioxide (TiO2) photocatalyst coated on glass beads was synthesized through a simple method and showed improved activity and durability. This material exhibited easy recovery and potential for large‐scale applications. The efficacy of the TiO2 nanoparticle‐deposited glass beads' (TiO2@GBs) photocatalyst in treating PFOS contaminants in wastewater was explored, demonstrating its ability to promote photocatalytic reactions to break down PFOS into shorter chain byproducts. The study employed the response surface method (RSM) using the Box–Behnken design (BBD) to optimize treatment conditions at a PFOS concentration of 0.1 mg/L. Investigated factors included pH (4–9), TiO2 dosage (0.11–0.53 g/L), and irradiation time (4–8 h). Design‐Expert 12 software was used to plan and optimize the experiments. Fifteen experiments were conducted, and triplicate runs occurred at the center points of the experimental plan. ANOVA and Fisher's test yielded an F value of 73.88 (p < 0.0001) which demonstrated the model's statistical significance with over 99% confidence regression prediction. The optimized treatment conditions that achieved 100% degradation of PFOS included a pH of 4.55, TiO2 dosage of 0.396 mg/L, and irradiation time of 6.59 hours. After the photocatalytic treatment, PFOS was transformed into intermediate products such as PFPeA, PFHpA, L‐PFBS, and L‐PFHxS. [ABSTRACT FROM AUTHOR]

The traditional specific storage coefficient (Ss) was defined under two assumptions. One is that aquifer rock deforms only in the vertical direction, and the other is that the average rock stress remains unchanged. Consequently, Ss is irrelevant to the shear modulus of rock (G). In this paper, the Biot theory is used to derive a new specific storage coefficient (Ss∗) with the natural deformation of rock. Ss∗ appears to be relevant to G. Compressed glass beads and Berea sandstone are used for illustration. At frequencies lower than 10 kHz, the equation of groundwater flow with Ss∗ yields the same phase velocity and quality factor as the Biot theory, and therefore, it is capable of accurately predicting fluid pressure diffusion in the low‐frequency regime. The results also show that Ss is 16%–17% higher than Ss∗. In conclusion, the latter one is superior to the former in its consistency with the Biot theory and unconstraint by the aforementioned two assumptions. [ABSTRACT FROM AUTHOR]

We carried out a petrological, mineralogical, and geochemical study of fragmental and regolith breccia clasts separated from two Chang'e‐5 (CE‐5) soil samples, CE5C0000YJYX03501GP and CE5C0400, which provide an opportunity to investigate the compositional change of regolith at the landing site through time. Fragmental breccia CE‐5‐B3 contains a diverse range of basaltic clasts and basaltic mineral fragments, and some rare Mg‐suite‐like minerals. Regolith breccias CE‐5‐B006, CE‐5‐B007, CE‐5‐B010‐08, CE‐5‐B010‐09, CE‐5‐B011‐07, and CE‐5‐B016‐03 contain mare basaltic fragments, mare vitrophyric clasts, rare Mg‐rich fragments possibly derived from the Mg‐suite rocks, and impact‐derived glass spherules. Pb‐isotope data obtained for baddeleyite grains found both inside some of the basaltic clasts identified in breccia fragments and in the breccia matrices yield Pb/Pb dates similar to the 2 Ga crystallization age of the CE‐5 basalt fragments, extracted directly from the soil sample. Seventy‐four Pb isotope analyses of Ca‐phosphate grains also indicate that the majority of these grains have Pb/Pb dates of 2 Ga, suggesting that they originate from the CE‐5 basalts. In addition, a Pb–Pb isochron drawn through analyses of four Ca‐phosphates in breccia CE5‐B006 yielded an intercept corresponding to a date of 3871 ± 46 Ma, which is the best possible estimate of the formation age of these four grains. Electron probe microanalysis shows that the breccias contain components similar to CE‐5 mare basalt fragments extracted directly from the soil sample, implying that the fragmental and regolith breccia fragments are mostly composed of material sourced from the underlying basalts. The general absence of impact melt breccia clasts, along with the general lack of Fe–Ni metal and absence of added meteoritic debris all suggest that the regolith at the CE‐5 landing site is immature and dominated by material mixed together by small local impact cratering events. Trace element analyses show that the glass beads in the regolith breccias have a Th abundance of 4.06–5.28 μg g−1. This is similar to the Th content of the regolith above the Em4 unit at the landing site as measured from orbit, as well as the estimated bulk Th content of CE‐5 basalts, suggesting that Th of the local regolith is predominantly sourced from the underlying mare basalts, without significant Th addition from Th‐rich exotic clasts sourced from evolved lunar lithologies. [ABSTRACT FROM AUTHOR]

The gravity-induced depth-dependent elastic properties of a granular half-space result in multiple dispersive surface modes and demand the consideration of material heterogeneity in metabarrier designs to suppress surface waves. Numerous locally resonant metabarrier configurations have been proposed in the literature to suppress Rayleigh surface waves in homogeneous media, with little focus on extending the designs to a heterogeneous half-space. In this work, a metabarrier comprising partially embedded rod-like resonators to suppress the fundamental dispersive surface wave modes in heterogeneous granular media known as first order PSV (PSV1; where P is the longitudinal mode and SV is the shear-vertical mode) and second order PSV (PSV2) is proposed. The unit-cell dispersion analysis, together with an extensive frequency-domain finite element analysis, reveals preferential hybridization of the PSV1 and PSV2 modes with the longitudinal and flexural resonances of the resonators, respectively. The presence of the cutoff frequency for the longitudinal-resonance hybridized mode facilitates straightforward suppression of the PSV1 mode, while PSV2 mode suppression is possible by tailoring the hybridized flexural resonance modes. These PSV1 and PSV2 bandgaps are realized experimentally in a granular testbed comprising glass beads by embedding 3D-printed resonator rods. Also explored are novel graded metabarriers capable of suppressing both PSV1 and PSV2 modes over a broad frequency range for potential applications in vibration control and seismic isolation. [ABSTRACT FROM AUTHOR]

Accurate topographic data are essential for quantitative structural analysis, both in natural settings and in the laboratory. The selection of modeling materials (with appropriate rheological properties) is known to be fundamental for the success of scaled physical analog experiments. However, the optical properties of analog materials and their impact on the reliability and precision of high‐resolution topographic reconstructions have not (to our knowledge) previously been assessed. Here we evaluate the effects of material composition, color, and grain size on Structure‐from‐Motion (SfM) photogrammetry reconstruction efficacy for deformed and undeformed model configurations in the laboratory. Image collections for photogrammetry are acquired from multiple camera positions with a handheld digital camera, and reconstructions are registered using ground control points in a local coordinate system. Static experiments show that low reflectivity granular materials (e.g., silica sand, volcanic ash, pumice, and Al2O3) yield relatively reliable photogrammetry data for a wide range of grain sizes (44–2,400 μm) but larger grain sizes (≥250 μm) provide more robust results. Reflective materials (e.g., glass beads, wet clay) yield less reliable point‐clouds but the addition of low‐reflectivity granular materials (e.g., Al2O3 grains) on the surface of wet clay improves reconstruction results, with higher grain densities typically yielding lower point‐cloud residuals. SfM‐photogrammetry reconstruction of deformed clay analog models tends to improve at higher extension magnitudes because of fault and associated texture development on model surfaces. We anticipate that our results will help practitioners to improve the precision and reliability of photogrammetric data acquired in the analog modeling laboratory. Key Points: Low‐reflectivity granular materials yield more reliable Structure from Motion topographic reconstructions than wet clay or reflective granular mediaApplication of granular material to wet clay surfaces improves the reliability and precision of model surface reconstructionsFault development imparts surface texture to model surfaces, improving topographic reconstruction results [ABSTRACT FROM AUTHOR]

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Oxytetracycline (OTC) is frequently detected in groundwater and soil, posing substantial risks to the subsurface environment via persistence, phytotoxicity, changing bacterial communities, and antibiotic resistance. In situ chemical oxidation (ISCO) is one of the best alternatives for removing OTC from groundwater. However, its feasibility has rarely been investigated using columns for which optimal conditions can be obtained for practical applications. Thus, a system consisting of oxygen-doped graphitic carbon nitride (OgCN) and peroxymonosulfate (PMS) (OgCN/PMS) was tested for OTC removal using continuous-flow experiments with columns packed with sand and glass beads (GBs). The sand column exhibited better adsorption and degradation of OTC than the GB column in pulse injection experiments, regardless of whether OgCN was packed. Additional experiments were performed using a column saturated with the OTC solution and another filled with deionized water to simulate ISCO, using GB as the medium, to evaluate the net OTC removal by catalytic oxidation, excluding adsorption. Performance improved with increased OgCN packing, PMS dosage, retention time, and pH. Anions slightly affected the performance due to scavenging and propagation of radicals. These findings indicate the high potential of OgCN/PMS for ISCO and the usefulness of column experiments in field applications. [ABSTRACT FROM AUTHOR]

Unconsolidated porous media are distinct from consolidated porous rocks in the negligible bulk and shear moduli. This paper is motivated by resolving the control mechanism of P-wave attenuation in the media (represented by Toyoura sands and glass beads) saturated with water. The first model is Biot theory in which longitudinal friction (arising from velocity difference between the two phases) is quantified using dynamic permeability as a function of frequency. The first model simulates phase velocity (Vp) and the ultrasonically measured quality factor (Qp) well. A second model is the transverse squirt model in which squirt is induced by pressure differential between contact of grains (COG) and the main pore space. The second model outputs unrealistic Vp and Qp. The results reveal that P-wave attenuation in unconsolidated porous media (saturated with water) is governed by longitudinal friction rather than intrapore squirt. Remarkably, low-frequency dynamic permeability is much smaller than Darcy permeability, indicating that ultrasonic P-wave is surprisingly capable of indirectly detecting the very narrow gap at COG. [ABSTRACT FROM AUTHOR]

In this work we present a novel, experimentally efficient set-up for performing non-contacting laser vibrometry on geologic materials and their analogues. We show it is possible to acoustically monitor a granular material experiment in real time compared to the typical timescale of analogue modelling experiments. We acquire non-contacting waveform data with consistently high signal-to-noise ratio. Compared to previously used standard contacting transducers, the novel joint use of sources and receivers that are both laser-based resulted in measured signals with improved waveforms and temporal bandwidths. These data acquisition improvements, in our case where surface waves are prominent in the data, enable enhanced multichannel surface wave processing, for example, in terms of reliable dispersion curve estimates. We find, given the high waveform fidelity of our acquisition system, that the observed surface waves are highly sensitive to relatively small changes in the medium's elastic properties, making them a demonstrably reliable to monitor any processes that affect elasticity in these models in near real time. As a demonstration, we continuously monitor a scaled analogue model containing granular glass beads. By continuously monitoring—that is, performing repeatable active-source acousto-seismic surveys at short time-lapse intervals—over a period of 10 hr, we find that an increase of relative humidity of 10 per cent can lead to as much as a factor of two increase in surface wave group velocities. Finally, we discuss future applications of the developed method by considering surface wave inversion for fault and stress monitoring during the deformation of a model. [ABSTRACT FROM AUTHOR]

Based on 3D printing technology, this paper investigates the effects of the printing process and reinforcement materials on the performance of 3D-printed glass bead insulation mortar. In order to improve and enhance the performance of the mortar, two sets of tests were designed for research and analysis. Firstly, by changing the direction of the interlayer printing strips, the anisotropy of the specimens in different paths was analyzed, and then the effect of different dosages of different fibers on the performance of 3D-printed glass bead insulation mortar was investigated by adding reinforcing materials. The results show that the path a specimen in the X direction's compressive strength is the best; in the Y direction, flexural strength is the best; the path b specimen in the Y direction's compressive strength is the best; in the Z direction, flexural strength is the best, but the compressive and flexural strengths are lower than the strength of the specimen without 3D printing (cast-in-place specimen); and adding reinforcing materials mortar not only has high strength but also has good printability and excellent thermal insulation. This paper provides a theoretical basis and reference value for the popularization and application of 3D printing thermal insulation mortar technology. [ABSTRACT FROM AUTHOR]

The focus of this study is the experimental characterization of cemented granular materials, with the aim of identifying the microscopic properties of the solid bonds and describing the extension to macroscopic mechanical strength of cemented samples. We chose to use artificially bonded granular materials, made of glass beads connected by solid paraffin bridges. The results of several sets of laboratory tests at different scales are presented and discussed. Micromechanical tests investigate the yield strength of single solid bonds between particles under traction, shearing, bending and torsion loading, as a function of variations in particle size, surface texture and binder content. Macro-scale tensile tests on cemented samples explore then the scale transition, including influence of confining walls through homothetic variations of the sample size. Despite the large statistical dispersion of the results, it was possible to derive and validate experimentally an analytical expression for micro tensile yield force as a function of the binder content, coordination number and grain diameter. In view of the data, an adhesive bond strength at the contact between bead and solid bond is deduced with very good accuracy and it is even reasonable to assume that the other threshold values (shear force, bending and torsion moments) are simply proportional to the tensile yield, thus providing a comprehensive 3D model of cemented bond. However, the considerable dispersion of the data at the sample scale prevents validation of the extended model for macroscopic yield stress. A final discussion examines the various factors that may explain intrinsic variability. By comparison with other more realistic systems studied in the literature in the context of bio-cementation, our artificial material nevertheless appears suitable for representing a cemented granular material. Being easy to implement, it could thus enable the calibration of discrete cohesion models for simulation of practical applications. [ABSTRACT FROM AUTHOR]

Archaeological research carried out in the Kruger National Park has identified several settlements of early African farmers that date to the Early Iron Age (EIA) – c. AD 200 – AD 1000. Two large EIA settlements, Le6 and Le7, were identified in 1977 on the southern bank of the Letaba River, opposite its confluence with the Tsende. Intermittent excavations of these sites were carried out between 1977 and 1989, but results have remained largely unpublished. These sites, which date back to the ninth century, have been the focus of new and ongoing research since 2021. The research has revealed that these communities were among the very first in the South African interior to participate in trade with the wider Indian Ocean world. This article contextualises the EIA of the Letaba River and surrounds with a specific focus on the history of research at Le6 and Le7 as well as briefly discusses new research at these sites. [ABSTRACT FROM AUTHOR]

This study explores the influence of flow velocity, sphere size, and inter-sphere distance on hydrodynamics and mass transfer in a photocatalytic reactor. The effects of two different light configurations on light distribution and degradation were also evaluated. A 2D computational fluid dynamics (CFD) model was developed to simulate the continuous flow photocatalytic reactor with TiO2-coated spheres and validated with experimental measurements by observing the degradation of methyl orange. The experimental setup consists of a tube containing an equal number of TiO2-coated glass spheres. The case with radiation from one wall shows a non-uniform light distribution compared with the case with radiation from both walls. The CFD simulations focused on analyzing the velocity streamlines and turbulence characteristics (turbulent kinetic energy (TKE) and turbulence dissipation rate (TDR)). These parameters showed significant variations in each studied case. The case with larger spheres reached the highest velocity of 38 m/s of the pollutant solution. The highest TKE and TDR values of 0.47 m2/s2 and 12.2 m2/s2, respectively, were also observed in the same case, indicating enhanced mixing and mass transfer to the catalyst surfaces, ultimately leading to a more efficient degradation process. The results show that an optimized design of photocatalytic reactors can significantly improve mass transfer and, thus, degradation efficiency. [ABSTRACT FROM AUTHOR]

Noise in the immunohematological investigations can be described as a false reactivity of red blood cells (RBCs) in serologic testing that is not related to the interaction of RBC antigens and antibodies that the test system is intended to detect. These false-positive reactions can cause confusion during the cross-matching and RBC antibody screening and may result in delays in patient transfusion. Although these antibodies are predominantly clinically insignificant, proper laboratory work-up is indicated to avoid misidentification of a clinically significant antibody as a noise. In this report, we describe the three rare cases where the reactivity was found against the ingredients of the column matrix (glass beads). It is imperative that such reactivity is recognized and resolved during the investigation of blood group discrepancies, positive RBC antibody screens and in cases of positive cross-matches. [ABSTRACT FROM AUTHOR]

This study investigates the impact of mechanical alteration on resin composite surfaces and its subsequent effect on repair bond strength. A total of 100 resin composite disks were prepared and were allocated for 24 h or 1 year of artificial aging. Specimens were embedded in epoxy resin, and the composite surfaces were mechanically altered using either diamond burs or air abrasion with aluminum oxide or glass beads. A universal bonding material was applied and a 2 mm circular and 3 mm high repair composite cylinder were prepared using a Teflon mold. Then, the specimens were tested for their shear bond strength, and the de-bonded specimens were observed under a scanning electron microscope to determine the failure pattern. SPSS 26.0 statistical software was used to analyze the data. Two-way ANOVA showed a statistically significant effect of mechanical alteration and aging on the shear bond strength of S-PRG-filler-based resin composite (p < 0.05). Surface modification with a fine diamond bur showed a significantly higher bond strength in both 24-h- and 1-year-aged specimens. Surface modification with alumina significantly increased the bond strength of 1-year-aged specimens; however, it was statistically insignificant for 24 h-aged specimens. Mechanical alteration with a fine diamond bur and 50-micron alumina can improve the repair bond strength of the composite. [ABSTRACT FROM AUTHOR]

At present, syntactic foam composites (HGB/EP) made of epoxy resin (EP) and hollow glass beads (HGBs) have received extensive attention in the research field of lightweight materials because of their high compression strength‐to‐density ratio. However, the deep‐sea environment has put forward higher requirements for the compressive properties of materials. The traditional sandwich structure with HGB/EP as the core has gradually failed to meet the requirements for the mechanical properties of equipment deeper in the ocean. This paper proposes a sandwich structure comprising a pure EP H‐shaped structural component as the rigid skeleton and an HGB/EP syntactic foam composite as the lightweight filling component. The pure EP H‐shaped structural component was subjected to flame treatment using a butane flame jet at different distances. The compression resistance of the resulting sandwich structure was tested, and the results showed varying degrees of improvement in compressive strength after flame treatment. The effects of flame treatment on the surface adhesion performance of the pure EP were characterized using compression‐shear tests, optical microscopy, contact angle tests, infrared spectroscopy, and flame temperature tests. The results demonstrated that flame treatment at a distance of 0 cm significantly increased the oxygen‐containing functional groups on the surface of the pure EP, improved the wettability of the pure EP surface, increased the adhesive strength between the pure EP H‐shaped structural component and HGB/EP, and enhanced the compressive strength of the sandwich structure. The shear strength of the shear test specimens improved by 33.0%, while the compressive strength of the sandwich structure specimens increased by 17.5%. Highlights: The sandwich structure composed of pure epoxy resin H‐shaped structure and foam composite material was prepared.The distance of flame treatment affects the surface chemical groups of epoxy resin.Flame treatment significantly improved the surface wettability of epoxy resin. [ABSTRACT FROM AUTHOR]

Solid–liquid two-phase centrifugal pumps are important fluid transport components in production and life. Most of the studies about the influence of solid-phase parameters on fluid transport mostly focus on single-component solid particles. In this work, two kinds of glass beads with particle sizes of 2 mm and 0.4 mm were used to study the effect of the binary mixed particle volume concentration on the internal flow and wear characteristics of a centrifugal pump. The flow distribution of the binary mixed particles in a centrifugal pump and the interactions between the particles and flow components at different volume concentrations (Cv = 5%, Cv = 7.5%, Cv = 10%, Cv = 12.5%, Cv = 15%) were studied using a Computational Fluid Dynamics-Discrete Element Method (CFD-DEM). The research results show that with the increase in particle volume concentration, the head and efficiency of the pump decrease. Additionally, the distributions of the particles with different concentrations in the impeller flow passage were obtained. Moreover, the coupling force of the flow field acting on the particles decreases with the increase in particle concentration and the time it takes to convey small particles decreases with the increase in concentration, while that of large particles decreases first and then increases. Furthermore, the contact force between the particles and the blade changes periodically with time, and the wear of the centrifugal pump is mainly concentrated on the pressure surface of the blade and the wall of the volute outlet side; the wear rate increases as the particle concentration increases. [ABSTRACT FROM AUTHOR]