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Purpose: To investigate the effects of recycling lithium disilicate (LD), surface treatment, and thermocycling on the bond strength to resin cement. Materials and Methods: A total of 72 tablets (10 × 10 × 3 mm) of LD were made according to the recycling cycle with 24 tablets for each strategy: control (conventional sintering), 1R (1 recycling cycle), and 3R (3 recycling cycles). For the recycling groups, tablets were waxed, mounted in a silicone ring, and poured with investment material, and residues of sintered LD tablets were pressed by the lost wax technique. The residual LD was reused as described until it reached 3R. Afterward, the tablets were embedded in acrylic resin, sanded, and divided (n = 15) according to the factors of "surface treatment" (hydrofluoric acid [HF] for 20 seconds [HF20s] and silane, HF for 120 seconds [HF120s] and silane, and Monobond Etch & Prime [MEP]) and thermocycling (TC; with 10,000 cycles and without). After surface treatment, cylinders (diameter: 2 mm) of resin cement were made and submitted to SBS test (100 kgf, 1 mm/minute). Data (MPa) were analyzed by three-way ANOVA, Tukey test (5%), and Weibull analysis. Failure analysis was performed with a stereomicroscope. Results: ANOVA revealed that all factors were significant (P = .000*). The group 3RMEP (105.09 ± 19.49) presented the highest SBS among the experimental groups. The 1RHF20sTc (7.50 ± 1.97) group had the lowest SBS, similar to CHF20sTc (15.69 ± 3.77), 1RHF20s (15.12 ± 3.03), 1RHF120sTc (14.60 ± 3.43), and 3RHF20sTc (15.65 ± 0.97). The Weibull modulus and characteristic strength varied among the experimental groups (P = .0). Failure analysis revealed adhesive and mixed types. Conclusions: The recycling of DL ceramics increases the SBS to resin cement when the ceramic is treated with HF120s and silane or MEP. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of different finishing protocols on the wear behavior of lithium disilicate glass-ceramics (LD). Materials and Methods: Specimens were produced from LD prefabricated CAD/CAM blocks and divided into three groups according to the surface treatment (n = 8): control, polishing, and glaze. Ceramic specimens were subjected to wear testing using a dual-axis chewing simulator. A 49-N load was applied in the axial direction combined with a lateral movement (1-mm path) using an LD spherical piston for a total of 106 cycles. Qualitative analysis of the wear surface was performed using an optical microscope. Quantitative analysis of surface roughness and volume loss was performed using a confocal microscope and a 3D-image editing software, respectively. Surface roughness and volume loss data were analyzed using Friedman's nonparametric statistical test for repeated measures and the Student-Newman-Keuls test (a = .050). Results: There were statistical differences for surface roughness and volume loss of LD specimens in the different experimental conditions (P < .001). The control and polishing groups showed similar surface roughness and volume loss values for all testing times. The glaze group had greater wear volume after 103, 104, and 105 cycles. After 106 cycles, surface roughness and volume loss were similar in all groups. For the piston, surface roughness was similar over time and among groups. Conclusions: A distinct wear behavior was found for glazed glass-ceramic specimens compared to control and polished specimens. At the end of the simulation, the surface roughness and volume loss was similar for the groups. [ABSTRACT FROM AUTHOR]

In this work, three atomic layer deposition (ALD) approaches are used to deposit an Al2O3 gate insulator on n-GaN for application in vertical GaN power switches: thermal ALD (ThALD), plasma-enhanced ALD (PEALD), and their stacked combination. The latter is a novel method to yield the most ideal insulating layer. Also, the influence of an in situ NH3 or H2 plasma pre-treatment is studied. Planar MIS capacitors are used to investigate the electrical properties and robustness of the gate insulators. In vacuo x-ray photoelectron spectroscopy (XPS) is used to study the changes in chemical composition after every surface treatment. XPS shows that all plasma pre-treatments efficiently remove all carbon contamination from the surface, but only NH3 plasma is observed to additionally remove the native oxide from the n-GaN surface. The water precursor step in the ThALD process does not completely remove the CH3 ligands of the trimethylaluminum precursor step, which might electrically be associated with a reduced forward bias robustness. The O2 plasma step in the PEALD process is associated with the removal of carbon and a tremendous increase of the O content in the GaN surface region. Electrically, this strongly correlates to an enhanced forward bias robustness and an increased forward bias hysteresis, respectively. The ThALD/PEALD stack method mitigates the shortcomings of both ALD processes while maintaining its advantages. Electrical measurements indicate that the stack method alongside NH3 plasma pretreatment provides the best characteristics in terms of hysteresis, threshold voltage, forward bias robustness, and interface trap density of states. [ABSTRACT FROM AUTHOR]

The effects of corona-discharged atmospheric plasma treatment on the surfaces of polyvinyl chloride (PVC) were studied for their application in adhesively joining PVC with AA 6061 aluminium alloy. Although no alteration has been observed in the topography of the treated PVC surfaces, ATR-FTIR analysis reveals the incorporation of –OH functional groups. Therefore, the untreated hydrophobic surface of PVC changes to a hydrophilic nature after corona treatment. Single lap shear (SLS) specimens were prepared using treated PVC and Al bonded with a room temperature cure epoxy adhesive. The obtained SLS strength of the joint between 20-second treated PVC and etched Al is found to be 15 times larger than that of untreated PVC with as-received Al. [ABSTRACT FROM AUTHOR]

Background: The purpose of this in vitro study was to compare the surface roughness (Ra) changes of different dental ceramic materials with different compositions, which were applied two different surface treatments after exposure to acidic pH. The purpose of this in vitro study was to compare the Ra changes of different CAD-CAM materials with different compositions, which were applied two different surface treatments, after exposure to acidic pH. Methods: A total of the 168 samples (12 × 14 × 2 mm) were obtained from ceramic blocks (IPS e.max CAD (LDS)), GC Cerasmart (RNC-C), Lava Ultimate (RNC-L), and Vita Enamic (PIC). Half of each group was subjected to mechanical polishing, and the other half was glazed. After the initial Ra evaluations were made, the samples classified with 7 in each subgroup were kept in three different solutions (citric acid, Coca-Cola, and artificial saliva-control group). After 168 h, surface roughness values of the specimens were measured again. Results: In the RNC-C samples, varying surface treatments and exposure to various solutions did not produce a statistically significant difference. Different acidic solutions did not affect the Ra values of LDS and RNC-C ceramics. The percentage change in Ra values in the glazed samples of PIC exposed to Coca-Cola and RNC-L exposed to artificial saliva were higher than those applied mechanical polishing. Conclusion: The Ra values of RNC-C ceramics were not affected by both surface treatment and acid exposure. The percentage change in Ra values was highest in PIC ceramics. In general, glazed samples had larger Ra change values and higher percentage change in Ra values than manually polished ones. [ABSTRACT FROM AUTHOR]

Despite the high survival rates of dental implants, peri-implantitis is a prevalent complication. Peri-implantitis is related to biofilm that adheres to the surface of implants and causes peri-implant chronic inflammation and bone destruction. Different surface treatments have been proposed to prevent biofilm formation. The objective of this systematic review was analyzing different types of antimicrobial coatings and identifying the most effective one(s) to control bacterial colonization over extended periods of analysis. We performed a bibliographic search in Pubmed and Cochrane base of articles published after 2010 to answer, according to the PICO system, the following question: What is the most effective antibacterial surface coating for dental implants? Only papers including a minimum follow-up bacteria growth analysis for at least 48 h were selected. After selection, the studies were classified using the PRISMA system. A total of 40 studies were included. Three main categories of coatings were identified: Antibacterial peptides, synthetic antimicrobial molecules (polymers, antibiotics, ...), and metallic nanoparticles (silver). Antibacterial peptide coatings to modify dental implant surfaces have been the most studied and effective surface modification to control bacterial colonization over extended periods of incubation as they are highly potent, durable and biocompatible. However, more in vitro and pre-clinical studies are needed to assess their true potential as a technology for preventing peri-implant infections. [ABSTRACT FROM AUTHOR]

Hydrothermal synthesis has been used to produce one-step boron nitride (BN) films on glass surfaces at low temperatures. The effect of various modifications (acidic and alkaline etching, sandpaper abrading) of glass surfaces on the morphological and optical properties of the films was investigated using different characterisation techniques. SEM images confirmed the formation of nanoflower morphologies, and BN nanolayers with a 200–300 nm diameter were grown vertically on the glass surface. XPS, FT-IR, and XRD analysis proved the formation of the boron nitride phase on glass surfaces. While changing the etching time did not significantly change the morphology, it significantly affected the photoluminescence properties. It was determined that the most effective etchings were hydrofluoric acid (HF) and alkaline etching. The films formed with these modifications had fewer defects and were more homogeneous. Moreover, this one-step and easy method proves that boron nitride nanolayers can be deposited with different surface modifications without forming a seed layer on the glass surface. [ABSTRACT FROM AUTHOR]

With an aim to address the issue of poor corrosion resistance in magnesium alloys, we implemented ultrasonic rolling pretreatment on magnesium alloy AZ31, followed subsequently by N-ion implantation treatment. The influences of various implantation doses on the surface structure and friction-corrosion performance of the magnesium alloy were examined. The outcomes disclosed that after N-ion implantation, a new phase Mg3N2 emerged, and the diffraction peak intensity increased as the implantation dose rose. The microhardness of the modified surface layer rose significantly with higher implantation doses due to the formation of nitrides and solid solution strengthening caused by N implantation. The results of the friction wear test showed that the average friction coefficient of the magnesium alloy samples decreased from 0.33 to 0.28 after ion implantation treatment. Notably, the samples with an implantation dose of 5 × 1016 ions/cm2 had the minimum mass loss during wear and demonstrated superior wear resistance, which was in line with the reduced friction coefficients. Electrochemical analysis indicated that increasing the implantation dose enhanced the self-corrosion potential of magnesium alloy samples from −1.39 (for the untreated sample) to −1.19 and significantly decreased the self-corrosion current density due to the diffusion protection provided by Mg3N2 formed on the surface along with the supersaturated nitrogen diffusion effect. These discoveries demonstrate that combining the ion implantation process following ultrasonic rolling pretreatment can further enhance the tribocorrosion resistance of magnesium alloys and serve as a valuable reference for improving the surface properties of these alloys through composite processes. [ABSTRACT FROM AUTHOR]

Porous asphalt (PA) pavement usually has a short service life due to the ravelling distress. Spraying surface treatment (ST) asphalt emulsion could alleviate it. However, the effects of ST on the short- and long-term mechanical performances of PA mixture are unclear. Therefore, this study used repeated axial load test, indirect tensile fatigue test and indirect tensile cracking test to evaluate the rutting, fatigue and cracking resistances of damaged PA under different curing durations, respectively. Two curing temperatures, 25 and 60°C, were considered here. Results showed that the mechanical properties of ST treated PA were significantly improved in short-term. The durability of mechanical properties is good based on long-term observation data. The rutting resistance of treated PA was not compromised if the application rate of ST is well controlled. A high curing temperature could expedite recovery efficiency of damaged PA, but it was accompanied by faster aging, which cannot be ignored. [ABSTRACT FROM AUTHOR]

The long-term success of dental implants depends on the ability of soft tissues to form a protective barrier, limiting pathogen infiltration into peri-implant tissues. Here, we investigated the impact of an anodized surface modification on mucosal integration. Scanning electron microscopy and surface chemistry characterization were carried out on miniaturized implants. Following placement in fresh extraction sockets of mice, peri-implant tissues were examined at 4 time points. Histology along with quantitative immunohistochemistry for Keratin14, Vimentin, Laminin5, and CD68 were carried out on postimplant day (PID) 3 to assess early events in soft-tissue repair; on PID7, when peri-implant epithelialization was complete; at PID14, when osseointegration was complete; and at PID28, when soft-tissue maturation was nearing completion. In all cases, an intact junctional epithelium served as a reference. These analyses supported 3 conclusions: first, maturation of the peri-implant epithelium (PIE) is a protracted process, consistent with clinical observations. Second, maturation of the soft tissue–implant interface is slower than maturation of the bone-implant interface. Third, there is a benefit, albeit transient, to soft-tissue maturation around an anodized implant surface. Given its prolonged time course, strategies to improve and/or accelerate PIE maturation are likely to have significant clinical benefit. [ABSTRACT FROM AUTHOR]

Dental implants undergo a general surface treatment via micro-blasting, where solid particle erosion (SPE) occurs on their surfaces. Considering the high costs of SPE experiments, it is necessary to present a reliable computer simulation that can provide a correct understanding of the erosion rate, residual stress and the characteristics of the scar created. However, simulating the impacts of numerous erosive particles with different shapes is challenging. This article, using numerical and experimental approaches, focused on effects of particle velocity and angle of impact on the surface responses of Ti-6Al-4V. In the simulation, the real shapes of more than 1500 angular particles were reproduced through an image processing technique. Johnson-Cook/Zerilli-Armstrong constitutive model was established for analysis. The accuracy of finite element (FE) and smoothed-particle hydrodynamics (SPH) was compared with experiments at oblique and normal micro-blasting in three velocities. Erosion rate, residual stress and scar area were investigated. Higher velocities showed more accurate erosion rate results with SPH, whereas the FE model suited lower ones. SPH outperformed FE in predicting surface residual stress. For normal impacts, the SPH was more reliable in predicting the scar area, while the FE was more accurate for oblique impacts. SEM results indicated both penetration and cutting mechanisms at 35°, but only pure penetration was the main mechanism at 90°. [ABSTRACT FROM AUTHOR]

This study aims to investigate the behaviour of thermoplastic composites reinforced with natural fibres. Composite materials were developed using reactive methyl methacrylate (MMA) resin, commercially known as Elium® (Arkema, Colombes, France), with the incorporation of cellulose nanocrystals (CNCs), dispersed in the matrix at different concentrations. Natural fibres, such as flax, were chemically treated by immersion in an aqueous solution based on NaHCO3, during different periods of exposure. After this treatment, flax fibres were washed with distilled water and dried. The degree of fibre surface tension was measured in terms of the contact angle. Then, cellulose nanocrystals were incorporated and mixed in the thermoplastic resin, and the samples were developed via the incorporation of intercalated layers of treated flax fibres. The composites were produced using compression moulding. After that, the samples were evaluated, regarding their mechanical performance and morphology. The research results show that flax fibres treated with 9 wt. % NaHCO3 for 48 h had improved flexural strength as a result of removing impurities and exposing hydroxyl groups that react with Na+ ions present in NaHCO3, which enhances its mechanical properties. The incorporation of 1% CNCs into thermoplastic resin significantly enhanced the fibre/matrix interface, resulting in a remarkable 38% increase in flexural strength. These findings demonstrate the effectiveness of using treated natural fibres and CNCs to improve composites' performance. [ABSTRACT FROM AUTHOR]

In this study, a surface treatment process was introduced into the conventional dispersion process for preparing wet-laid nonwoven fabrics to improve their properties, using recycled carbon fibers (rCFs). The conventional binder solution was replaced with a solution containing different amounts of silane, and the changes in the fiber properties of the prepared nonwoven fabrics were examined after the addition of modified rCFs and polypropylene. FE-SEM analysis confirmed that a silane layer was formed on the rCF surface due to the formation of a siloxane network. FT-IR and XPS analyses further confirmed the presence of siloxane bonds and chemical modification of the rCF surface. When an optimal amount of silane content was used, the mechanical strength increased by 64% compared to untreated rCFs, owing to the improved molecular chain entanglement within the matrix. Our findings indicate that the simultaneous use of dispersion and a surface treatment can produce composites with excellent mechanical properties and improved processing and surface properties; thus, this method can be used to help upcycle rCFs, thereby expanding their applications. [ABSTRACT FROM AUTHOR]

This study investigated the influence of plasma electrolytic oxidation (PEO) preparation time on the degradation resistance of Mg-1Zn (Z1) and Mg-1Zn-0.4Ca (ZX10) alloys, with comparisons to pure Mg and commercial Mg-4Y-3RE-0.4Zr (WE43). PEO layers were formed with varying preparation times (5, 10, and 15 min) and analyzed for microstructure, morphology, and corrosion resistance. The results indicated that PEO layers with a 10 min preparation time had the most homogeneous structure and optimal corrosion resistance. Prolonged PEO preparation times increased pore density, crack formation, and layer thickness while also promoting layer degradation during extended immersion in 0.9% NaCl corrosive media. The dissolution of phosphates from PEO layers contributes to the formation of a protective corrosion layer, enhancing long-term resistance. These findings demonstrate that low-alloyed, biocompatible Mg-Zn(-Ca) alloys can achieve corrosion resistance comparable to high-performance WE43 alloys through appropriate surface treatment. [ABSTRACT FROM AUTHOR]

The interfaces between the perovskite and charge-transporting layers typically exhibit high defect concentrations, which are the primary cause of open-circuit voltage loss. Passivating the interface between the perovskite and electron-transporting layer is particularly challenging due to the dissolution of surface treatment agents during the perovskite coating. In this study, a coherent FAPbIxCl3−x buried interface was simultaneously formed during the preparation of FAPbI3. This interlayer significantly improved charge extraction and transportation from the perovskite layer, while reducing trap state density. As a result, the open-circuit voltage increased from 1.01 V to 1.10 V, with the PCE improved from 19.05% to 22.89%. [ABSTRACT FROM AUTHOR]

Surface treatment for sink rolls in continuous galvanizing lines is an important issue due to the unfavorable environment of the molten zinc. This study investigated the corrosion behavior of high-velocity oxy liquid fuel (HVOLF) sprayed WC-12Co, Hybrid-LVOF sprayed Al 2 O 3 -TiO 2 , and Al 2 O 3 coatings in molten zinc bath. All coated samples were tested in a zinc bath for 30 days and cross-sectioned to examine the microstructure and corrosion attack. The results were checked and compared. The results showed that the molten zinc reacts with coating material causing major destruction of HVOLF sprayed WC-12Co. Whereas Hybrid-LVOF sprayed dense Al 2 O 3 -TiO 2 and Al 2 O 3 coatings performed very well for longer exposure times of 30 days in a molten zinc bath environment. The structural integrity and no penetration of Zn into the coating were observed without any thickness reduction in both coatings. However, Zn accumulation was observed on the Al 2 O 3 -TiO 2 coating surface and Zn reacted with TiO 2 and form Zn 2 TiO 4. Whereas no Zn reaction was taking place with Al2O3 coating. Further no stress has been generated in the Al 2 O 3 coating. A very small amount of γ-Al 2 O 3 is present which upon exposure converts to stable α-Al 2 O 3. MECPL Jodhpur has developed a special process to solve this problem, and it could greatly improve the service life of a sink roll. [ABSTRACT FROM AUTHOR]

The interfaces between the perovskite and charge-transporting layers typically exhibit high defect concentrations, which are the primary cause of open-circuit voltage loss. Passivating the interface between the perovskite and electron-transporting layer is particularly challenging due to the dissolution of surface treatment agents during the perovskite coating. In this study, a coherent FAPbIxCl3−x buried interface was simultaneously formed during the preparation of FAPbI3. This interlayer significantly improved charge extraction and transportation from the perovskite layer, while reducing trap state density. As a result, the open-circuit voltage increased from 1.01 V to 1.10 V, with the PCE improved from 19.05% to 22.89%. [ABSTRACT FROM AUTHOR]

To compare the push-out bond strength of adhesive resin cement and glass fiber posts (GFP) at different root levels after exposure to Er: YAG laser irradiation compared to other conventional surface treatment procedures. A total of 24 mandibular premolars were decoronated, root canal treatment was done, post spaces were prepared, and roots were mounted in acrylic resin blocks. Fiber posts were divided into four groups (n = 6) according to surface treatment methods: (1) silane only (control group), (2) Er: YAG laser 1.5 W + silane, (3) 30% hydrogen peroxide + silane, (4) sandblasting with 50 μm aluminum oxide particles + silane. GFP were cemented using self-adhesive resin cement. Scanning electron microscope images with 500x magnification were taken for all groups. Push-out test was performed using a universal testing machine at different root levels. The difference between groups was statistically significant with laser group recording the highest mean ± SD value of push-out bond strength (5.668042 ± 1.16 MPa), followed by the H2O2 group, then the control group, meanwhile the lowest value was recorded with Sand-blasting group. There were no statistically significant differences between the Control group and Er: YAG group; Control group and sandblasted group. The difference between the radicular regions was not statistically significant, with the middle region recorded the highest push-out bond strength (4.746851 ± 0.73 MPa). GPF surface treatment using an Er: YAG laser is effective as it increases the retention to resin cement, while sandblasting decreases fiber post retention to resin cement. The hydrogen peroxide and the control groups give similar bond strength. The middle and apical regions of GFP have better retention to resin cement than the coronal one. [ABSTRACT FROM AUTHOR]

Bonding performance of carbon fiber/polyetherketoneketone (CF/PEKK) laminates is closely related to crystallinity and is influenced by growth, formation, and density of spherulites. Press consolidation, with its ability to adjust pressure, exhibits superior quality compared to oven consolidation. However, bonding and production of CF/PEKK laminates using Press consolidation exhibit significant variations in quality depending on forming conditions. While research on producing CF/PEKK laminates using press consolidation is currently active, there is a lack of studies on co-consolidation for CF/PEKK laminates. Thus, in this study, establishment of forming process variables for press consolidation was conducted to achieve excellent bonding performance for CF/PEKK. Furthermore, IR heating-assisted surface heat treatment was employed to enhance bonding performance of CF/PEKK laminates by controlling crystallinity and spherulites. To analyze bonding performance, short bean shear testing was conducted to obtain interlaminar shear strength (ILSS). Results showed that surface modification through IR heating led to an increase in crystallinity and a noticeable growth in size of spherulites. In specific conditions, improved bonding performance was observed. This is judged to be primarily due to increase in spherulite size and crystallinity at bonding interface, attributed to specific conditions of both surface treatment through IR heating and Press consolidation. [ABSTRACT FROM AUTHOR]

Objectives: Repair of composite resin restorations is a challenge specially when the restoration undergoes aging; thus, this study aimed to assess the effect of aging and different surface treatments on the repair microshear bond strength of IPS Empress Direct nanohybrid composite resin. Materials and Methods: This in vitro, experimental study evaluated 48 IPS Empress Direct composite resin samples in two groups of aged and nonaged (n=24). The samples in both groups were finished and polished with Sof-Lex discs. Composite samples in the aged group were subjected to 5000 thermal cycles. The two groups were then divided into two subgroups (n=12) for surface roughening by a diamond bur or sandblasting with aluminum oxide particles. Composite cylinders were then bonded to the composite samples, and underwent microshear bond strength test in a universal testing machine. Data were analyzed by two-way ANOVA and t-test (alpha=0.05). Results: The results showed no significant difference in the microshear bond strength of bur and sandblasted subgroups, irrespective of aging (P>0.05). In the aged subgroups, however, irrespective of the method of surface treatment, the bond strength was significantly lower than that in the subgroups that did not undergo the aging process (P<0.05). Conclusion: Micromechanical retention is the most reliable method to achieve a high repair bond strength in IPS Empress Direct composite resin. Surface roughening by bur is safe and cost-effective, and can be used instead of sandblasting for composite restoration repair. [ABSTRACT FROM AUTHOR]

Natural fiber composites are widely explored sustainable alternative to conventional composites in many applications. However, since they are weak compared to conventional composites, various surface treatments are adopted to improve their overall mechanical properties. The effect of glow discharge air plasma treatment of banana and pineapple leaf (PALF) natural fibers is investigated and presented in this study. Fibres were treated for different time periods, their surface were analysed, and composite laminates with standalone and hybrid were fabricated. Tensile, flexural and impact tests in different combinations of reinforcements were carried out. Spectroscopic, thermal and microscopic characterisations like Fourier-transform infrared spectroscopy (FT-IR), X-Ray diffraction (XRD), Thermogravimetric analysis (TGA), Field Emission Scanning Electron Microscopy (FESEM) were used to study the fibre surface, 3D digital microscope was used to study the fractography and a water absorption test was carried out to study the hydrophilicity were carried out to characterise the fibre surface and the laminates. Significant variations in thermal stability and improvements in tensile strength (even up to 275%) and flexural properties were observed. This investigation revealed the cause of the same was due to the enhancement in crystallinity, mechanical interlocking and improved fibre-matrix adhesion, which was evident from characterizations. [ABSTRACT FROM AUTHOR]

Throughout their lifetime, trees store valuable environmental information within their wood. Unlocking this information requires quantitative analysis, in most cases of the surface of wood. The conventional pathway for high-resolution digitization of wood surfaces and segmentation of wood features requires several manual and time consuming steps. We present a semi-automated high-throughput pipeline for sample preparation, gigapixel imaging, and analysis of the anatomy of the end-grain surfaces of discs and increment cores. The pipeline consists of a collaborative robot (Cobot) with sander for surface preparation, a custom-built open-source robot for gigapixel imaging (Gigapixel Woodbot), and a Python routine for deep-learning analysis of gigapixel images. The robotic sander allows to obtain high-quality surfaces with minimal sanding or polishing artefacts. It is designed for precise and consistent sanding and polishing of wood surfaces, revealing detailed wood anatomical structures by applying consecutively finer grits of sandpaper. Multiple samples can be processed autonomously at once. The custom-built open-source Gigapixel Woodbot is a modular imaging system that enables automated scanning of large wood surfaces. The frame of the robot is a CNC (Computer Numerical Control) machine to position a camera above the objects. Images are taken at different focus points, with a small overlap between consecutive images in the X-Y plane, and merged by mosaic stitching, into a gigapixel image. Multiple scans can be initiated through the graphical application, allowing the system to autonomously image several objects and large surfaces. Finally, a Python routine using a trained YOLOv8 deep learning network allows for fully automated analysis of the gigapixel images, here shown as a proof-of-concept for the quantification of vessels and rays on full disc surfaces and increment cores. We present fully digitized beech discs of 30–35 cm diameter at a resolution of 2.25 μ m, for which we automatically quantified the number of vessels (up to 13 million) and rays. We showcase the same process for five 30 cm length beech increment cores also digitized at a resolution of 2.25 μ m, and generated pith-to-bark profiles of vessel density. This pipeline allows researchers to perform high-detail analysis of anatomical features on large surfaces, test fundamental hypotheses in ecophysiology, ecology, dendroclimatology, and many more with sufficient sample replication. [ABSTRACT FROM AUTHOR]

In recent years, solvent‐driven actuators have been capable of controlling deformations in response to external stimuli. However, a magnetic polydimethylsiloxane (PDMS) composite film with magnetic properties is traditionally developed using the micro‐electro‐mechanical system process. Although it has general actuation deformation, the composite film suffers from the problems of actuation and control. Here, this is done by co‐mixing PDMS and ferrosoferric oxide (Fe3O4) then waiting for curing and then undergoing ultraviolet‐ozone (UVO) surface treatment. By adjusting the time and orientation of the UVO treatment, a series of solvent‐driven actuators with multiform steady‐state structures (e.g., mono/bistable helix) is proposed. In addition, the deformation of the composite film under different geometrical parameters and surface constraints was visually predicted by incorporating finite element analysis methods. In addition, the controlled deformations of the composite film (such as box‐like, folded, and so on) are carried out by self‐morphing design. Finally, four bionic applications are also proposed to demonstrate the practical use of soft actuators based on Fe3O4‐PDMS films in bionic robots. This work provides new strategies for designing and fabricating programmable and controllable soft actuators and lays the foundation for a wide range of smart material applications. [ABSTRACT FROM AUTHOR]

Laser-assisted cold spraying (LACS) is garnering significant interest as an innovative surface treatment technology that integrates cold spray technology with laser. However, the primary role of laser on in-flight particles remains underexplored. This study aims to elucidate the impact of laser on in-flight particles through meticulously designed experiments and comprehensive multi-physical field simulations, in which the in-flight iron and nickel particles were heated by the laser parallel to the substrates and deposited on the substrates, while the substrates were not heated by the laser. The cross-sectional microstructures, porosity, oxygen content and microhardness of the coatings were characterized to assess the effect of the laser on the in-flight particles. The heating behavior of the in-flight particles under varying velocity and laser power was evaluated using multi-physical field simulations. The results indicated that the microstructures and properties of the coatings, including porosity, flattening ratios, oxygen content and microhardness, were not significantly influenced by the laser irradiation. The simulations further revealed that the laser irradiation had negligible effect on the temperature variation of the in-flight particles, attributed to the short duration time of laser exposure. The investigation enhances our understanding of the mechanism of LACS. [ABSTRACT FROM AUTHOR]

The escalating presence of antibiotic-resistant bacteria (ARB) in food systems presents a pressing challenge, particularly in preventing contamination and ensuring food safety. Traditional sanitation methods, such as cooking and chemical disinfectants, provide effective means to reduce ARB, yet there is a growing need for additional preventive measures directly on food surfaces. This review explores the potential of chitosan–phytochemical composites (CPCs) as surface coatings to prevent the initial contamination of food by ARB, thereby offering a novel complementary approach to conventional food safety practices. Chitosan, combined with active plant-derived metabolites (phytochemicals), forms composites with notable antibacterial and antioxidant properties that enhance its protective effects. We examine CPC synthesis methodologies, including chemical modifications, free radical-induced grafting, and enzyme-mediated techniques, which enhance the stability and activity of CPCs against ARB. Highlighting recent findings on CPCs' antibacterial efficacy through minimum inhibitory concentrations (MIC) and zones of inhibition, this review underscores its potential to reduce ARB contamination risks on food surfaces, particularly in seafood, meat, and postharvest products. The insights provided here aim to encourage future strategies leveraging CPCs as a preventative surface treatment to mitigate ARB in food production and processing environments. [ABSTRACT FROM AUTHOR]

Electroless nickel–phosphorus (Ni–P) plating is a widely used surface treatment method due to its excellent corrosion and wear resistance properties. However, the inertness of copper to hypophosphite oxidation necessitates a palladium activation process for the preparation of Ni–P coating on copper. In this study, a convenient approach is presented for the deposition of a cobalt layer on copper using galvanic replacement, facilitated by the special complexing ability of iodide. The results demonstrated that the actual potential of copper could be adjusted to be lower than that of cobalt in a solution containing 8 mol L−1 NaI, enabling the deposition of a cobalt layer on copper in 15 min at 90 °C. Furthermore, the deposition rate of the cobalt layer was found to increase with the concentration of CoCl2 in the NaI solution. Importantly, the Ni–P coating obtained through cobalt layer activation from either acidic or alkaline plating solution exhibited morphology, structure, corrosion resistance, and tribological performance similar to the Ni–P coating obtained using the common palladium activation. The Ni–P coatings obtained through cobalt and palladium layer activation from alkaline plating solution had a larger thickness than the Ni–P coating obtained from acidic plating solution. Therefore, the cobalt layer prepared on copper through galvanic replacement may serve as a viable alternative to palladium for activating electroless Ni–P plating. [ABSTRACT FROM AUTHOR]

Objectives: This retrospective cohort study aimed to compare and evaluate the 1-year stability of two Korean implant brands, Osstem and Toplan, both treated with alumina- sandblasting and acid- etching (SA) surface modification. Methods: This retrospective analysis evaluated patients with American Society of Anesthesiologists grade I or II, >20 years, with alveolar bone volume suitable for implant placement, who received immediate or delayed placement after extraction, and with Osstem (n = 57) or Toplan (n = 87) implants. The insertion torque value (ITV) measured on the day of implant placement and the implant stability quotient (ISQ) measured on the day of implant placement, 1 month post-surgery, and 2–3 months after implantation were analyzed. Results: Both implants had significantly increased ISQs over time, and the ISQs did not significantly differ between Osstem and Toplan implants at any time point. Osstem implants showed significantly higher ISQs in D2 than in D3 bone, and in the mandible than in the maxilla at all time points. Toplan implants with diameters >4.0 mm showed higher initial ISQs. Osstem implants showed a significant correlation between ITV and ISQ on the day of placement (r = 0.349, p < 0.01) but not at later time points. For Toplan implants, no significant correlation was confirmed between ITV and ISQ at any time point. At the 1-year follow-up, both implants were still providing functional service. Conclusions: Osstem and Toplan implants with SA surface treatment showed a high level of stability for 1 year, and no significant difference in stability was observed between the two implants. Both implants are considered clinically reliable products. [ABSTRACT FROM AUTHOR]

High-friction surface treatments can improve roadway safety by increasing the pavement friction. Macrotexture and microtexture are primary contributors to pavement friction. Macrotexture has established protocols for measurement, but no standardized methodologies exist for direct microtexture measurement. Additionally, there is a need for standard laboratory methods for assessment of aggregate microtexture for friction applications. This study developed and assessed a novel laboratory test to directly measure the microtexture of bulk aggregate samples using high-resolution laser scanning. Five abrasion resistant aggregates were evaluated at various gradations. Laser profiles were filtered to isolate microtexture band wavelengths. Spatial (micro-MPD, micro-RMS, micro-Ra), statistical (micro-Rsk, micro-Rku), and frequency domain [Log(power spectral density slope and intercept)] parameters were evaluated for repeatability and ability to distinguish among aggregates at various gradations. The effects of Los Angeles abrasion (LAA) and microdeval (MD) abrasion on the microtexture were also assessed. Acceptably repeatable microtexture measures were produced by the test method. ANOVA showed a significant effect of gradation on microtexture parameters. The laboratory methods were able to adequately predict texture on high friction surface treatment (HFST) samples made from the same aggregate at equivalent gradation under particular conditions. MD resulted in a decrease in microtexture depth, while LAA had no statistically significant effect. Similarly, MD led to a decrease in British pendulum test friction for all aggregates while the LAA produced mixed results indicating the advantages of MD over LAA in simulating friction and texture loss due to traffic abrasion. Once calibrated, regression models of the microtexture parameters showed acceptable modeling coefficients with a logarithmic fit of micro-MPD providing the highest R2 of 0.81. In comparison with macrotexture parameters from the same profiles, microtexture was a superior predictor of friction. The laboratory method developed can augment currently relied upon aggregate quality measures such as abrasion resistance to aid in the selection of suitable HFST aggregates. [ABSTRACT FROM AUTHOR]

As one of the lightest metallic structural materials, magnesium (Mg) alloys possess numerous distinctive properties and are utilized across a broad spectrum of applications. However, the poor corrosion resistance of Mg alloys limits their application. Micro-arc oxidation (MAO) is an effective surface treatment method that enhances the corrosion resistance of Mg alloys. Nevertheless, the intrinsic porous structure of MAO coatings hinders significant improvement in corrosion resistance. Research indicates that the pre- and post-treatment processes associated with MAO markedly enhance the densification of the oxide coatings, thereby improving their overall performance. This paper aims to provide a comprehensive review and analysis of the effects of various pre- and post-treatment processes, highlighting key advancements and research gaps in improving MAO coatings on Mg alloys. An in-depth analysis of the crucial role of pre-treatment in optimizing interfacial bonding and post-treatment in enhancing coating density is conducted using electrochemical testing and scanning electron microscopy (SEM). Finally, the future development of pre- and post-treatment processes are discussed. [ABSTRACT FROM AUTHOR]

The non-aqueous sol–gel method is widely used to prepare metal oxides due to its superior ability to modulate nanostructures. However, Li1.2Mn0.54Ni0.13Co0.13O2, a lithium-rich manganese-based material synthesized by this method, exhibits a high specific surface area. This high surface area can increase side reactions and cause a rapid decline in capacity. Sulfur doping on the surface of the material is achieved through secondary modification with thiourea treatment, resulting in enhanced electrochemical properties and stability. Elemental and morphological characterization, along with electrochemical testing, shows that sulfur surface doping effectively mitigates the rapid capacity decay associated with a high specific surface area. The high specific surface area, combined with the lattice broadening effect of sulfur doping, is significantly improving the kinetic polarization of the cell and enhancing both its performance and cycle stability. At 0.1C, the specific capacity of the cell increases from 244.4 mAh/g to 274.2 mAh/g in the first cycle. Additionally, the capacity retention rate improves from 48 to 70% after 300 cycles at 1C. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the dynamic mechanical properties of the 2519a aluminum alloy and the effects of water jet (WJ) strengthening on its fatigue performance. Initially, the stress–strain behavior of 2519a aluminum alloy under different strain rates and temperatures was studied using the Split Hopkinson Pressure Bar (SHPB) test, and the Johnson–Cook (J–C) constitutive model for the 2519a aluminum alloy was established. The numerical analysis model for WJ strengthening and the fatigue life after WJ strengthening was constructed using finite element software ABAQUS and Fe-safe, and the numerical results were verified through experiments. The findings indicate that the dynamic mechanical properties of the 2519a specimens exhibit strain rate sensitivity and temperature softening behavior. The surface roughness of the specimens after WJ strengthening is positively correlated with the jet velocity, with the average surface roughness being approximately 1.1 μm, 1.6 μm, and 1.9 μm, respectively. The maximum residual compressive stress in the specimens is positively correlated with the jet velocity; as the jet velocity increases from 150 mm/s to 210 mm/s, the induced maximum residual compressive stress is approximately 102.5 MPa, 161.8 MPa, and 174.5 MPa, respectively. The depth of the maximum residual compressive stress is 102.9 μm, 102.9 μm, and 114.2 μm, respectively. With the increase in jet velocity, the increase in the amplitude of the maximum residual compressive stress gradually decreases, but the depth of the maximum residual compressive stress significantly increases. Therefore, it is considered that controlling the jet velocity and optimizing the jet parameters can achieve a better induction of residual compressive stress. Additionally, the fatigue life cycle count of the specimens is positively correlated with the WJ velocity, with the cycle count increasing by 118% and 116% at the same WJ velocity interval, and the fatigue cycle count of the specimens after WJ-210 mm/s strengthening is 137% higher than that after WJ-150 mm/s strengthening. The crack fracture morphology after WJ strengthening was also analyzed. This study pioneers the use of WJ for surface treatment of 2519a aluminum alloy, providing a viable reference scheme for effectively and economically improving the fatigue performance of 2519a aluminum alloy. [ABSTRACT FROM AUTHOR]

Stainless steel 17-4PH is valued for its high strength and corrosion resistance but poses machining challenges due to rapid tool wear. This research investigates the use of pulsed electron beam surface treatment to enhance the surface properties of components fabricated by binder jetting additive manufacturing. The aim is to improve the tribological performance compared to the as-sintered condition and the H900 aging process, which optimizes hardness and wear resistance. Printed samples were sintered in a reducing atmosphere and superficially treated with an electron beam by varying the voltage and the pulse count. Results showed that the voltage affects the roughness and thickness of the treated layer, while the number of pulses influences the hardening of the microstructure and, consequently, the wear resistance. A reciprocating linear pin-on-disk wear test was conducted at 2 N and 10 Hz. Surface-treated samples exhibited lower coefficients of friction, though the values approached those of aged samples after the abrasion of the melted layer, indicating a deeper heat-affected zone formation. Still, the friction remained lower than that of as-printed specimens. This study demonstrates that optimizing electron beam parameters is vital for achieving surface performance comparable to bulk aging treatments, with significant implications for long-term wear resistance. [ABSTRACT FROM AUTHOR]

The mechanical and tribological characteristics of a thermal barrier coating are highly critical in gas turbine applications to resist high-temperature oxidation, corrosion, and solid particle erosion. In the present investigation, a composite coating with alumina and samarium strontium aluminate has been developed through a plasma spraying process. The as-coated composite top coat consisted of three phases α-alumina, ϒ-alumina, and Sm2SrAl2O7. The as-coated surface is re-engineered with an Nd: YAG fiber laser to improve the mechanical and microstructural properties. The laser-treated samples showed a better erosion resistance than the as-coated samples. Despite the surface treatment, both the as-coated and the laser-treated samples showed a higher 'average erosion value' at an impact angle of 90° for the test temperatures of 200 and 800 °C. In addition, the as-coated and the laser-treated samples have a higher erosion rate at 800 than at 200 °C for the selected impact angles, with a mixed mode of material removal presenting both ductile and brittle failure mechanisms. [ABSTRACT FROM AUTHOR]

The bolt axial force of high-strength bolted frictional glass fiber–reinforced polymer (GFRP) joints is reduced by the viscoelastic behavior of the GFRP matrix resin. In this study, the long-term relaxation characteristics of GFRP joints with hot-dip galvanized, coated connecting plates were clarified. Long-term relaxation tests were performed by varying the connecting conditions and material properties, such as the presence or absence of the GFRP coating, applied bolt axial force, presence or absence of hot-dip galvanization and surface treatment of the connecting plates, GFRP base member thickness, and fiber content. Phosphate treatment of the galvanized steel plates exhibited a negligible effect on the relaxation properties of GFRP joints. The bolt axial force reduction rate was accelerated by utilizing hot-dip galvanized plates or GFRPs with low fiber contents. This study provides insights into the long-term relaxation characteristics of GFRP joints with specific coatings, thus contributing to safer, more durable, and cost-effective infrastructure solutions, while also fostering advancements in materials science and engineering. Practical Applications: This research examined the changes in bolted joint strength in fiber-reinforced polymer (FRP) structures over time due to various factors such as bolt type, joint material, and environmental conditions. Our findings revealed that even after 30 years, the joints maintain strength well above the standard required, ensuring long-term reliability. This is particularly important for structures for which safety and durability are crucial, such as bridges and buildings in seismic areas. The study also highlights that specialized coatings and treatments, such as phosphate or galvanized surfaces, have a minimal effect on joint strength. This suggests that simpler, cost-effective methods can be employed without compromising safety. This has practical implications for construction and maintenance, offering ways to extend the life of existing structures and reduce the costs for new ones. By understanding these factors, engineers can design safer, longer-lasting FRP joints, contributing to more sustainable infrastructure development. This research provides valuable insights into enhancing the longevity and performance of bolted joints, ensuring that these critical connections withstand the challenges posed by time and environmental factors. [ABSTRACT FROM AUTHOR]

The increasing use of large glass surfaces in modern architecture requires robust adhesive solutions that balance aesthetic appeal with structural resilience, particularly in timber–glass applications. This study examines the influence of primer treatments on the shear performance of timber–glass adhesive joints, employing a combination of experimental testing and simulation techniques. Double-lap shear tests with epoxy adhesives assess the impact of various surface treatments on joint stiffness, shear stress distribution, and deformation. Additionally, a finite element model is developed to simulate joint behavior, evaluate failure modes, and analyze displacement patterns. Results indicate that primer applications notably enhance structural integrity by reducing displacement and increasing joint stability, thereby supporting more durable timber–glass assemblies. These findings offer valuable insights for advancing adhesive technologies in architectural components, enabling a closer alignment between structural performance and design innovation in timber–glass systems. [ABSTRACT FROM AUTHOR]

Recent studies to examine feasibility of alkali activated material (AAM) as bonding agent between substrate and overlay concrete were either metakaolin based AAM or fly ash–based AAM. Till date, limited studies were carried out to investigate suitability of ground granulated blast furnace slag (GGBS) based alkali activated materials as bonding agent between substrate and overlay concrete. Therefore, in the present study an attempt has been made to use GGBS based AAM as bonding agent between substrate and overlay. In addition, cement paste and epoxy were also used as bonding agents for comparison. Three types of surface preparation to substrate concrete viz. smooth surface (without any surface preparation), wire-brushed surface and rough surface were used along with bonding agents to examine the effect of substrate surface preparation on the behavior between substrate and overlay concrete. Mechanical performance of substrate-overlay specimen was measured using slant shear test, split cylinder test, and modulus of rupture test. Test results indicated that choice of bonding agent and surface preparation method significantly affected the performance. Order of measured slant shear strength was: Epoxy composites > Cement paste composites > AAM composites > No bonding agent. For both split cylinder and modulus of rupture test, order of measured strength was: Epoxy composites > AAM composites > cement paste composites > composites with no bonding agent. If substrate-overlay concrete specimen without any bonding agent and without any surface preparation is taken as reference, AAM showed (160%–530%) relative slant shear strength, (368%–645%) relative split tensile strength and 158% relative modulus of rupture respectively. However, bonding agents could not enhance performance of composite specimens up to the level of monolithic specimens, whatever was the surface preparation. Rough surfaced composites with different bonding agents were able to alter the failure mode of composite specimens from pure adhesive failure to other modes. [ABSTRACT FROM AUTHOR]

This paper focuses on the evaluation of the surface pretreatment of glass specimens and its effect on the strength of bonded joints. The experimental portion of this study includes the testing of three types of surface treatments (degreasing, blasting and etching) and the use of three types of adhesives (two-component epoxy, instant cyanoacrylate and two-component acrylate). Surface roughness measurements and bond strength testing using the pull-off test and shear tests were performed on the samples. The results showed that surface etching in conjunction with the Auratech AR 708 acrylic adhesive provided the highest bond strength. These findings contribute to the development of more reliable and stronger bonded joints for industrial applications. Scientific knowledge lies in determining the effect of appropriate glass surface treatment on adhesive adhesion under load with respect to joint aging due to environmental effects (UV, temperature, humidity) for transparent adhesives. This study provides an assessment of the effect of surface cleanliness on adhesion to glass. [ABSTRACT FROM AUTHOR]

In this paper, the Gyroid triply periodic minimal surface is prepared by liquid crystal display photopolymerization technology, and 10 models of the periodic parameter T in [1/5, 2] are designed. Using the method of finite element method and experimental verification, when T = 1/3, there are fewer stress concentration areas on the Gyroid surface, the number of grids is moderate, the compression crush rate is the smallest, and the porosity error is reasonable. Through the microscopic morphology, it is found that the surface, after printing, forms gear shape and resin residue so that the actual volume is larger than the theoretical volume, and the porosity is minor. Keeping periodic parameter T = 1/3 and porosity of 50%, four kinds of Gyroid surface structures were designed by changing the parameter surface offset, wall thickness, offset thickness, and gradient arrangement. The effects of different loading directions on its mechanical properties, deformation behavior, and energy absorption were discussed through compression experiments. The results show that the vertical load is applied to form a fault zone from the upper left angle to the lower right angle of 45°, and the parallel load is applied to create a fault zone from the upper right angle to the lower left grade of 45°. When the load is used in the vertical direction, the energy absorption and energy efficiency of the surface offset Gyroid surface are the largest. When the load is applied in the parallel order, the energy absorption curves of the four structures change similarly, and the deformation amplitude of the wall thickness Gyroid surface during the compression process is relatively stable. The energy efficiency of gradient arrangement Gyroid surface increases fastest in the compaction stage. [ABSTRACT FROM AUTHOR]