Surface Characteristics Of Substrates Research Articles

Comparative study of print quality attributes on bio-based biodegradable plastic using flexography and gravure printing process

Printing has revolutionized not only the religious and educational world by providing printing on paper but also the commercial world by providing end-to-end solutions for packaging by printing on materials like plastics. Print quality refers to level of details and sharpness of printed products for wider acceptability. Print quality has an important role in maintaining consistency during printing on selected surfaces to provide desired satisfaction. Printability and runnability of substrates, substrate surface characteristics, and printing ink properties are attributes of print quality and are considered important for determining good quality printing. Solid ink density (SID), Hue error, grayness and ink trapping are some of the important measurable printability factors that play an important role in determining the print quality irrespective of substrates. Gravure printing and flexography printing are high-speed printing suitable for printing on flexible substrates so, attempts were made for explore the mutual compatibilities of new-generation printing substrates with established printing processes, which will prove to be a boon in the future by replacing conventional plastics with bio-based biodegradable plastics in printing for packaging and its other applications. So, multi-color printing on selected bio-based biodegradable plastics were explored for determining printability by measuring and maintaining print quality attributes during print runs.

Perovskite Solar Cell on Stainless Steel Substrate over 10% Efficiency for Building-Integrated Photovoltaics

This study investigated the integration of perovskite solar cells (PSCs) on stainless steel (SS) substrates for application in building-integrated photovoltaics (BIPV). Using advanced atomic force microscopy measurements, we confirmed that enhanced substrate roughness increased the reflectance along an interface. Consequently, a remarkable final efficiency of 11.9% was achieved. Notably, PSCs, known for their exceptional efficiency of 26.1%, can overcome the inherent efficiency limitations of SS-based thin-film solar cells. In this study, a PSC with an efficiency of 14% was fabricated on a flexible SS substrate. This study is a significant step towards advancing sustainable energy solutions for BIPV applications. The global shift towards renewable energy sources has catalyzed intensive research and development efforts, rendering the exploration of alternative materials and manufacturing processes a priority. The success of PSCs on SS substrates underscores their promise to achieve a balance between efficiency and versatility in BIPV solutions. Moreover, our findings reveal that controlling the substrate surface characteristics can significantly enhance the performance of PSCs, offering a pathway toward greater energy efficiency and sustainability in the construction industry.

2D Hybrid Perovskites Employing an Organic Cation Paired with a Neutral Molecule.

Two-dimensional (2D) hybrid perovskites harness the chemical and structural versatility of organic compounds. Here, we explore 2D perovskites that incorporate both a first organic component, a primary ammonium cation, and a second neutral organic module. Through the experimental examination of 42 organic pairs with a range of functional groups and organic backbones, we identify five crystallization scenarios that occur upon mixing. Only one leads to the cointercalation of the organic modules with distinct and extended interlayer spacing, which is observed with the aid of X-ray diffraction (XRD) pattern analysis combined with cross-sectional transmission electron microscopy (TEM) and elemental analysis. We present a picture in which complementary pairs, capable of forming intermolecular bonds, cocrystallize with multiple structural arrangements. These arrangements are a function of the ratio of organic content, annealing temperature, and substrate surface characteristics. We highlight how noncovalent bonds, particularly hydrogen and halogen bonding, enable the influence over the organic sublattice in hybrid halide perovskites.

Ink Fluidic Behaviors during R2R Slot Die Coating on Quality Thin Film Formation

High throughput slot die coating is a desired fabrication method for flexible display, solar cell, Li-ion battery pack, intelligent package and wearable electronics. In this study, the stability of the thin film formation by slot die coating is investigated through theoretical, experimental and numerical studies with the combined effects of the fluid and substrate surface characteristics. The theoretical model based on the viscous capillary theory reveals fluid upstream and downstream distribution patterns and associated parameters that descript the coating layer stability. A 3D model based on the volume of fluid method (VOF) is developed to illustrate the coating process affecting the coating quality by the substrate velocity and flow rate. The numerical and experimental results agree that higher viscosity fluid is more prone to trap air bubbles and/or to create de-wetting areas while as the lower viscosity fluid were responsible for upstream liquid dripping. Boundary by the fluid, substrate, and operating parameters, our numerical study has developed the coating operation window to minimize or eliminate coating defects which has been confirmed by the experiments. These study results could lead high yield coating processes and efficiency in large area functional coating production.

Influence of the Crystallographic Texture of ITO on the Electrodeposition of Silver Nanoparticles

Metal nanoparticles exhibit physical and chemical properties that differ significantly from macroscopic metal phases. In particular, silver nanoparticles (NPs) had have extensive attention since it has a strong interaction with light due to their high quality localized surface plasmon resonances, which can be tuned all across the visible to the NIR regime. These strong and tuneable interaction of visible light with silver NPs have found many applications, in sensing, surface enhanced Raman spectroscopy, photo(electro)catalysis, and more.Polycrystalline indium tin oxide (ITO) films are highly desired substrates for many of these optoelectronic applications. In many of these applications, it is essential to reliably and precisely control the size and density of silver NPs. Even though it is well known that the electrochemical control over nucleation and growth of silver NPs on foreign substrates highly depends on the surface properties of the substrate, yet, the only parameter that is often specified for these ITO substrates is a bulk property: sheet resistance. As a result, nucleation and growth on ITO is highly irreproducible.In this work, we show that ITO substrates with same technical specifications (i.e. sheet resistance, light transmittance and roughness) and supplier may still have different surface properties such as the crystalline texture. We find that these differences in the surface properties has a strong impact on the nucleation and growth. Even though we used seemingly equal ITO substrates, XRD and EBSD scans clearly differentiate between two types of films based on the ratio between the (222) and (400) related peaks. We controlled the density and size of the silver NPs by making use of the double pulse technique. In this method, where the high overpotential nucleation pulse controls the nucleation density. Previous studies have reported an empirical exponential relationship between island density and nucleation pulse overpotential, where the slope is a measure for the electron kinetics.We find that the preferential presence of lower index surfaces (e.g. (100)) leads to few orders of magnitude lower particle density compared to the preferential presence of higher index surfaces (e.g. (111)). Furthermore, the density on the lower index surface is strongly dependent on the nucleation pulse overpotential, while the higher index surface is barely affected. We find that this difference in the relationship is caused by mass transport limited nucleation. We have verified this through a spatial correlation analysis using the nearest-neighbour distance. For higher index surfaces, the nucleation density is already large compared to the Nernst diffusion length at low nucleation pulse overpotentials, such that the limiting mechanism becomes mass transport instead of electron kinetics. We therefore elucidate that the empirical exponential relationship between island density and nucleation pulse overpotential is not enough to draw conclusions on electrode kinetics, where additional validation of the growth process is essential.Beyond careful control of electrochemical parameters, here we show that neglecting the macroscopic surface characteristics of polycrystalline substrates can lead to major ambiguity in nucleation and growth dynamics of metal nanoparticles. We show here that XRD characterization prior to deposition is a simple additional measure to tailor metal nanoparticle electrochemical growth on ITO.

Experimental investigation on the change of pull-off force between bulk particulate material and an elastic polymeric filter fiber

HypothesisAdhesion between particles and a filter fiber is an important process of the filtration as it dictates the process of separation and in the following the detachment process of particles during filter regeneration. In addition to the shear stress that a new polymeric stretchable filter fiber implements into the particulate structure, the elongation of the substrate (fiber) is also expected to cause a structural change in the surface of the polymer. Thus, the changed contact area and surface energy could affect the adhesion force between particles and fibers. ExperimentsSystematic measurements of adhesion forces between a single particle and the stretchable substrate were performed using Atomic Force Microscope (AFM). The substrate surface characteristics (roughness) was changed directly beneath the modified measurement head using piezo-motors to achieve stepless elongation state. Polystyrene particles and particles made of Spheriglass were applied. FindingsIn the experiments, a reduced adhesion force between the particles and the filter fiber was found for a new high range of substrate roughness and peak-to-peak distance, in which the Rabinovich model has not been used before [1]. Further, the influence of high and low energy surface particulate material was evaluated to understand the detachment process in the new real adaptive filter and in DEM-simulation.

Influence of PHA Substrate Surface Characteristics on the Functional State of Endothelial Cells

The needs of modern regenerative medicine for biodegradable polymers are wide and varied. Restoration of the viability of the vascular tree is one of the most important components of the preservation of the usefulness of organs and tissues. The creation of vascular implants compatible with blood is an important task of vascular bioengineering. The function of the endothelial layer of the vessel, being largely responsible for the development of thrombotic complications, is of great importance for hemocompatibility. The development of surfaces with specific characteristics of biomaterials that are used in vascular technologies is one of the solutions for their correct endothelialization. Linear polyhydroxyalkanoates (PHAs) are biodegradable structural polymeric materials suitable for obtaining various types of implants and tissue engineering, having a wide range of structural and physicomechanical properties. The use of PHA of various monomeric compositions in endothelial cultivation makes it possible to evaluate the influence of material properties, especially surface characteristics, on the functional state of cells. It has been established that PHA samples with the inclusion of 3-hydroxyhexanoate have optimal characteristics for the formation of a human umbilical vein endothelial cell, HUVEC, monolayer in terms of cell morphology as well as the levels of expression of vinculin and VE-cadherin. The obtained results provide a rationale for the use of PHA copolymers as materials for direct contact with the endothelium in vascular implants.

Experiments to understand bubble base growth mechanism(s) on hydrophobic surfaces under the influence of bulk flow inertia during nucleate boiling regime

Wetting characteristics of substrate surface is one of the parameters that strongly influence the phenomena of boiling heat transfer. In this direction, importance of hydrophobic surfaces has been emphasized in the literature due to their potential to offer high boiling heat transfer rates at low heat fluxes. For such surfaces, it has been shown that microlayer ceases to exist with contact line evaporation being the dominant bubble base growth mechanism during nucleate pool boiling regime. The present work investigates the plausible mechanism(s) of bubble growth on hydrophobic surfaces under nucleate flow boiling conditions. Possibility of formation of microlayer even on low wettability surfaces under the influence of bulk flow inertia has been examined. Thin-film interferometry, in conjunction with high-speed videography, has been configured to record the microlayer dynamics and the bubble growth process in tandem. For a direct comparison, experiments under identical flow and bulk subcooled conditions have also been performed on a hydrophilic substrate, which is known to promote microlayer formation during the bubble growth process. Observations made through thin-film interferograms confirmed the formation of microlayer on hydrophobic surfaces. Experiments further revealed that the rate of growth of dry patch is higher on hydrophobic surfaces than that in the case of hydrophilic substrates. Vapor bubbles have been observed to be pinned on the hydrophobic surface whereas the phenomenon of bubble lift-off has been distinctly observed on hydrophilic substrate surface.

Plasma-Modified PI Substrate for Highly Reliable Laser-Sintered Copper Films Using Cu2O Nanoparticles.

Plasma modification of polyimide (PI) substrates upon which electrical circuits are fabricated by the laser sintering of cuprous oxide nanoparticle pastes was investigated systematically in this study. Surface properties of the PI substrate were investigated by carrying out atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS), and contact angle measurements. Experimental results show that surface characteristics of PI substrates, including surface energy, surface roughness, and surface binding significantly affected the mechanical reliability of the sintered copper structure. Among the plasma gases tested (air, O2, Ar-5%H2, and N2-30%H2), O2 plasma caused the roughest PI surface as well as the most C=O and C–OH surface binding resulting in an increased polar component of the surface energy. The combination of all those factors caused superior bending fatigue resistance.

Surface modification of magnesium alloys using thermal and solid-state cold spray processes: Challenges and latest progresses

• Diverse surface modification techniques for Mg and its alloys are introduced. • Mechanical, tribological and corrosion behavior of thermal sprayed coatings are presented. • Benefits and restrictions of the cold spray (CS) process are introduced. • The latest development of cold spray (CS) process for industrial applications is presented. • Bonding mechanism at the Mg alloy/cold sprayed layer interface is introduced. Potential engineering applications of magnesium (Mg) and Mg-based alloys, as the lightest structural metal, have made them a popular subject of study. However, the inferior corrosion and wear characteristics significantly limit their application range. It is widely recognized that surface treatment is the most commonly utilized technique for remarkably improving a substrate's surface characteristics. Numerous methods have been introduced for the surface treatment of Mg and Mg-based alloys to improve their corrosion behavior and tribological performance. Among these, thermal spray (TS) technology provides several methods for deposition of various functional metallic, ceramic, cermet, or other coatings tailored to particular conditions. Recent researches have shown the tremendous potential for thermal spray coated Mg alloys for biomedical and industrial applications. In this context, the cold spray (CS) method, as a comparatively new TS coating technique, can generate the coating layer using kinetic energy rather than combined thermal and kinetic energies, like the high-velocity oxy-fuel (HVOF) spray method. Moreover, the CS process, as a revolutionary method, is able to repair and refurbish with a faster turnaround time; it also provides solutions that do not require dealing with the thermal stresses that are part of the other repair processes, such as welding or other TS processes using a high-temperature flame. In this review paper, the recently designed coatings that are specifically applied to Mg alloys (primarily for industrial applications) employing various coating processes are reviewed. Because of the increased utilization of CS technology for both 3D printed (additively manufactured) coatings and repair of structurally critical components, the most recent CS methods for the surface treatment, repair, and refurbishment of Mg alloys as well as their benefits and restrictions are then discussed and reviewed in detail. Lastly, the prospects of this field of study are briefly discussed, along with a summary of the presented work.

Effects of Substrate Surface Characteristics on the Adhesion Properties of Geopolymer Coatings.

Geopolymer is a kind of material with a better ability of high-temperature and corrosion resistance. Poor adhesion could easily lead to problems such as coating cracks, peeling at an early stage, and inability to work with the substrate. The adhesion depends on many factors such as chemical composition of the raw materials, the formulation of the geopolymer, the type of substrate, surface roughness of the substrate, etc. The higher the Si/Al ratio, the greater the shear strength of the coating. This is because geopolymers synthesized with different Si/Al ratios have different phases in the geopolymer binder. Each study uses different multi-parameter combinations selected by itself, which is not uniform and has no universal applicability. As the parameter Ra is determined by the profile centerlines of the substrate surface, it is difficult to get an appropriate value of Ra to represent the roughness of the substrate surface. The parameter-relative area, determined by area scale fractal analysis, can effectively characterize the surface roughness, predict the texture component of bond strength, and establish a connection between which and the bonding performance of the geopolymer coating at a high level of confidence. The bonding strength reduces with the decrease in the value of the relative area. The magnitude of scale employed should be seriously determined when characterizing the surface roughness.

Inhibition of focal adhesion turnover prevents osteoblastic differentiation through β-catenin mediated transduction of pro-osteogenic substrate.

The mechanism by which substrate surface characteristics are transduced by osteoblastic cells and their progenitors is not fully known. Data from previous studies by our group suggest the involvement of β‐catenin in the mechanism by which substrate surface characteristics are transduced. This focal adhesion and β‐catenin mediated mechanism functions through the liberation of β‐catenin from focal adhesion complexes in response to pro‐osteogenic substrate (POS) characteristics. After liberation, β‐catenin translocates and facilitates upregulation of genes associated with osteogenesis. It is not known whether the observed correlation between focal adhesion turnover and β‐catenin translocation directly results from focal adhesion turnover. In this study we inhibited focal adhesion turnover using a focal adhesion kinase inhibitor PF‐573228. We found that inhibition of focal adhesion turnover resulted in an abrogation of the more rapid translocation and increased transcriptional activity of β‐catenin induced by POS. In addition, inhibition of focal adhesion turnover mitigated the increase in osteoblastic differentiation induced by a POS as measured by alkaline phosphatase enzymatic activity and osteogenic gene and protein expression. Together, these data, coupled with previous findings, suggest that the observed β‐catenin translocation is a result of focal adhesion turnover, providing evidence for a focal adhesion initiated, β‐catenin mediated mechanism of substrate surface signal transduction.

Enhanced cytocompatibility and mechanical properties of electron beam melted Ti-6Al-4V by friction stir processing

Electron Beam Melting (EBM) is an emerging additive manufacturing technique for the fabrication of titanium alloy Ti-6Al-4V for orthopedic applications. Here, a hybrid manufacturing technique viz. EBM with Friction Stir Processing (FSP) has been proposed to enhance implant surface properties. The surface modification using FSP reduces the roughness generated by the EBM technique from ~44.77 μm to ~15.82 μm. Simultaneously, FSP improves the biological and mechanical properties of the Ti-6Al-4V substrates. The roughness, wettability, amounts of ions released, and surface microhardness were measured to analyze the stability of the substrates. The effect of the hybrid processing strategy on cell viability was tested against mouse fibroblast cells NIH3T3 through MTT assay, and we found that the friction stir processed substrate (EBM-F) showed the highest cell viability. The EBM-F surface displays a two-fold increase in the cell-viability as compared to the unprocessed EBM surface after 24 h of cell-seeding. The FSP substrate allows human cervical cells HeLa to adhere onto its surface while selectively preventing the attachment of E.coli bacterial cells. These observations towards cells signify biocompatible surface characteristics of the FSP EBM substrate.

Growth mechanism and ablation behavior of CVD-HfC coating on the surface of C/C composites and CVD-SiC coating

HfC coatings were deposited on the surface of carbon/carbon (C/C) composites and CVD-SiC coating by low-pressure chemical vapor deposition (CVD), respectively. The effects of two substrates on the microstructure, phase composition and preferred orientation of HfC coatings were investigated in detail. Results showed that HfC coatings deposited on two substrates inherit their own substrate surface characteristics. After ablation for 90 s, the HfC coating prepared on CVD-SiC coating has better ablation resistance under oxyacetylene flame with heat flux of 2.4 MW/m2, because the transition layer can effectively relieve the damage caused by thermal stress.

Relationship between substrate type and BDD electrode structure, performance and antibiotic tetracycline mineralization

To comprehensively understand the relationship between substrate type and boron doped diamond (BDD) electrode structure, performance and antibiotic tetracycline mineralization, this work made a systematic evaluation of BDD electrodes prepared by the same process but based on different substrates, namely Si/BDD, Ta/BDD, Nb/BDD and Ti/BDD, in terms of microstructure, electrochemical properties, antibiotic tetracycline mineralization and accelerated service life. The results show that the physical and chemical properties of substrates have significant impacts on BDD film growth and microstructure. The substrate and film surface characteristics determined the physicochemical properties of BDD electrode. The growth rate of BDD film follows the sequence order as Si > Ta > Nb ≫ Ti. Ti/BDD electrode shows the higher oxygen evolution potential, lower background current, smaller electron transfer resistance, lower surface activity and shorter service life. Tetracycline can be completely removed by direct electron transfer or free radical mediated oxidization. On Ti/BDD electrode tetracycline removal and current efficiency are the second only to Si/BDD and the lowest electricity consumption can be obtained. Nb/BDD electrode shows slightly better performance than Ta/BDD electrode. Furthermore, the anode failure mode of Ti/BDD electrode was revealed.

Potentials of lignocellulosic agricultural residues in paper production

Surface characteristics of printing substrates are of the utmost importance to all types of paper that interact with ink. During all types of printing processes, the behaviour of the liquid phase (ink or dye) on the paper is directly defined by the paper cellulose-based surface. The printed ink spreads and penetrates more into paper fibres when the paper surface is rougher and more permeable. Contact angle measurements by sessile drop method are considered the most appropriate for determining the paper sheet surface energy. Paper as hydrophilic material has a high absorption rate resulting in a low contact angle. The objective of this study was to evaluate the surface free energy of laboratory-made papers containing straw pulp obtained from residues after the harvest of the most cultivated cereals in Croatia (wheat, barley and triticale). The obtained surface free energy results are promising for straw pulp usage in the manufacture of printing paper.

Substrate properties as controlling parameters in attached algal cultivation.

There is growing interest in attached algae cultivation systems because they could provide a more cost- and energy-efficient alternative to planktonic (suspended algae) cultivation systems for many applications. However, attached growth systems have been far less studied than planktonic systems and have largely emphasized algae strains of most interest for biofuels. New algal biorefinery pathways have assessed the commercial potentials of algal biomass beyond biofuel production and placed more emphasis on value-added products from that biomass. Therefore, algal strain selection criteria and biomass cultivation methods need to be updated to include additional strains for improved efficiency. One possible way of improving attached cultivation systems is through engineering substrate surface characteristics to boost algal adhesion and enable strain selective algal colonization and growth. This review explores the effect of substrate chemical and topographical characteristics on the cultivation of attached algae. It also highlights the importance of considering algal community structure and attachment mechanisms in investigating attached algae systems using the example of filamentous algae found in algal turf scrubber (ATS™) systems. KEY POINTS : • Attached algal cultivation is a promising alternative to planktonic cultivation. • Performance increase results from tuning surface qualities of attachment substrates. • Attachment adaptation of periphytic algae has innate potential for cultivation.

Hydroxyapatite Particle Density Regulates Osteoblastic Differentiation Through β-Catenin Translocation.

Substrate surface characteristics such as roughness, wettability and particle density are well-known contributors of a substrate's overall osteogenic potential. These characteristics are known to regulate cell mechanics as well as induce changes in cell stiffness, cell adhesions, and cytoskeletal structure. Pro-osteogenic particles, such as hydroxyapatite, are often incorporated into a substrate to enhance the substrates osteogenic potential. However, it is unknown which substrate characteristic is the key regulator of osteogenesis. This is partly due to the lack of understanding of how these substrate surface characteristics are transduced by cells. In this study substrates composed of polycaprolactone (PCL) and carbonated hydroxyapatite particles (HAp) were synthesized. HAp concentration was varied, and a range of surface characteristics created. The effect of each substrate characteristic on osteoblastic differentiation was then examined. We found that, of the characteristics examined, only HAp density, and indeed a specific density (85 particles/cm2), significantly increased osteoblastic differentiation. Further, an increase in focal adhesion maturation and turnover was observed in cells cultured on this substrate. Moreover, β-catenin translocation from the membrane bound cell fraction to the nucleus was more rapid in cells on the 85 particle/cm2 substrate compared to cells on tissue culture polystyrene. Together, these data suggest that particle density is one pivotal factor in determining a substrates overall osteogenic potential. Additionally, the observed increase in osteoblastic differentiation is a at least partly the result of β-catenin translocation and transcriptional activity suggesting a β-catenin mediated mechanism by which substrate surface characteristics are transduced.

Further Step toward a Comprehensive Understanding of the Effect of Surfactant Additions on Altering the Impact Dynamics of Water Droplets.

The addition of surfactants to pure water for specific applications has made controlling the impact dynamics of surfactant-laden droplets a complex phenomenon. This work investigates the influence of the molecular weight (MW), concentration, and ionic nature of the surfactants as well as the substrate surface characteristics on the impact dynamics of surfactant-laden droplets using a high-speed camera at 10 000 frames per second. Sodium dodecyl sulfate, hexadecyltrimethylammonium bromide, and n-decanoyl-n-methylglucamine were used as anionic, cationic, and nonionic surfactants, respectively. We used hydrophilic glass slides, hydrophobic polytetrafluoroethylene, and superhydrophobic alkyl ketene dimer (AKD) as substrates. The results show that the efficiency of the surfactant addition in increasing the maximum spreading diameter is significantly influenced by the molecular weight and ionic nature of the solutions as well as the nonwettability of the substrate. Among all of the surfaces examined, the concentration and ionic nature of the solutions were found to be more dominant parameters in determining the energy dissipation in the retraction phase of the droplet impact on the superhydrophobic AKD surfaces. As the concentration decreases or positive charges are present in the solution, it is more likely to observe a similar retraction dynamic to pure water when the droplet hits the superhydrophobic AKD having negatively charged surface sites. Finally, in terms of the impact outcomes of the surfactant-laden droplets on the superhydrophobic AKD, it is shown that the influence of the surfactant addition is more noticeable at lower Weber numbers, where the droplet tries to rebound by overcoming the energy loss that occurred in the spreading.

Spatial pattern and surface-specificity of particle and microorganism deposition and attachment: Modeling, analytic solution and experimental test

Hypothesis: Understanding microparticle and living cell deposition and attachment on surfaces from a flow is a long-standing surface-science problem, pivotal to developing antifouling strategies. Recent studies indicate a complex non-conservative and surface-specific nature of adhesion and mechanical contact forces that determine attachment kinetics. This requires new models and kinetic data, however, observed deposition rates (e.g., in parallel-plate flow chamber, PPFC) represent a superposition of attachment and bulk transport. Here, we propose to deduce attachment rates (as an appropriate rate constant) from spatial deposition profiles along PPFC and develop an analytical solution for the full problem, suitable for deposition data analysis and parameter fitting.Experiments: Analytical solution, validated by numerical simulations, reveals relation between the deposition profile along PPFC and key model parameter B, the ratio of sedimentation and attachment rates. Its use is demonstrated on experimental data obtained in a PPFC for particles and bacteria on various surfaces.Findings: Fitted B values highlight correlation with the particle/substrate nature and consistently explain the observed trends along PPFC, both decreasing and increasing. Thus derived attachment rates will serve as basis for future microscopic modelling that would relate attachment to appropriate surface and contact-mechanical characteristics of particles and substrate and flow conditions.