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In this study, the sol-gel stage co-precursor method was used to hydrophobically modify the gel and increase the content of alkali catalyst in the gel, thereby reducing the capillary force generated during ambient pressure drying and enhancing the strength of the gel skeleton. This improvement makes the gel skeleton structure not easy to destroy during the rapid drying process, thus greatly reducing the preparation time of atmospheric pressure drying, which could be as short as 10 h. It is worth mentioning that this method does not require extensive use of modifiers and organic solvents, so it has low cost, high efficiency, and broad industrial production application prospects. The experimental results show that the DDS/ZSA aerogel exhibits the lowest thermal conductivity (0.035 W m−1 K−1) when the dilute ammonia content is 5 ml. However, it should be noted that too low or too high an amount of dilute ammonia will lead to a decrease in aerogel performance, so it needs to be controlled within the appropriate range. In addition, the prepared aerogel has excellent hydrophobic properties with a contact angle greater than 140° and excellent thermal stability at 1000 °C, which can be used in harsh, humid, and high-temperature environments. [ABSTRACT FROM AUTHOR]

Polymeric composite materials are in great demand in biomedical and water treatment applications. This is because they possess distinct characteristics and can fulfill specific biomedical needs, in addition to their ability to degrade dyes. This study successfully synthesized sustainable strontium titanate (STO) particles with an average size of 120 nm using the solid-state method. When these STO particles were mixed into a PCL-based polyurethane matrix, the matrix became hydrophilic with a contact angle of 58.60° and its mechanical strength enhanced by 320%. The morphology and surface roughness of the films were determined using FESEM and AFM techniques. The antibacterial studies of polymeric composites film against E. coli, Klebsiella pneumonia, and S. aureus , showing good zone growth, and showing enhanced swelling properties of 270% for wound healing and biomedical applications. The photocatalytic performance of the STO by degrading Methyl Orange (MO) and Congo Red (CR) under UV light, achieving degradation efficiencies of 92.25% for MO and 62.5% for CR over 150 min. These findings suggest that PU scaffolds and STO are suitable for biological and water treatment in industrial applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The competitiveness between photovoltaic conversion efficiency (PCE) and transparency would be the bottleneck of transparent device for actual applications, as well as the high maintenance cost. In this work, the self-cleaning transparent device in interfacial Tb:Bi 2 Sn 2 O 7 QDs modified Cu 2 Y 2 O 5 /Bi 2 O 3 pn junction is prepared via a simple approach of sol-gel-hydrothermal method. The obtained Cu 2 Y 2 O 5 /Tb:Bi 2 Sn 2 O 7 QDs/Bi 2 O 3 exhibits high transmittance of ∼85 %, obvious photovoltaic enhancement of ∼2.0 × 103-folds (PCE of ∼1.17 %), stable output in 5 months cycles and a good self-cleaning via the hydrophobicity (contact angle of ∼123.4°). It's mainly attributed to the Tb:Bi 2 Sn 2 O 7 QDs and lamellar Bi 2 O 3 array. Besides appropriate potential and high quantum yield, the Tb:Bi 2 Sn 2 O 7 QDs, with the synergism of up-conversion fluorescence and interface/surface optimization, can improve the carrier kinetic equilibrium for achieving PCE-transparency balance, as well as increasing p-type conductivity through the synergism of Cu+/Cu2+ and interstitial oxygen. Moreover, the regular lamellar array can enhance solar efficiency via optimized surface, meanwhile achieving self-cleaning via the surface hydrophobicity and enhancing structural stability via the regular interval, making it being advantageous in actual applications of energy and information field, including windows, smart devices, etc. [ABSTRACT FROM AUTHOR]

Inspired by the antifouling process observed in fluorescent corals, this study introduces a novel functional antifouling film consisting of Ag-Cu 2 O nanocomposites, zwitterionic polymers, and a phosphor substrate. Zwitterionic polymers serve as a dispersive medium for Ag-Cu 2 O nanocomposites, enabling a uniform coating and optimal structural through spin-coating. During daylight hours, visible light irradiation excites Ag-Cu 2 O nanocomposites to produce reactive oxygen species (ROS), which cooperates with the hydration layer, exhibit a high-level antifouling effect. Notably, the unique structural coating can emit a weak coral-like fluorescence at night, sustaining ROS release and further enhancing antifouling performance. The assembly structure of the composite film was studied by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and water contact angle (WCA), while its antifouling performance was evaluated through antibacterial tests and a 30-day light-dark cycle anti-algae attachment experiment. The distinct nighttime antifouling capability contributes to 97.30 % anti-algae settled rate over a 30-day diurnal cycle. Moreover, we also investigated the effect of phosphor color on the composite film's antifouling properties. The blue phosphor group exhibited greater antifouling performance than the green or transparent phosphor group. The composite film created with multiple synergistic mechanisms exhibited auspicious antifouling performance. Further improvement and development of this composite film could unlock even greater potential for its antifouling properties. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA) or bioceramic-based coatings on stainless steel (SS) 316L significantly enhance the biofunctionality of the base material's surface. However, HA's low thermal conductivity and brittleness limit its effectiveness as a coating material. This study investigates HA coating on SS 316L using electric discharge machining (EDM) with varying discharge energies and powder concentrations. Surface morphology, elemental composition, and phase analysis of untreated and coated samples were characterised using field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD). The results demonstrate that the HA-assisted EDM process creates a coating comprising biocompatible oxides, phosphates, carbides, and intermetallic compounds. The coating exhibits a thin resolidified layer of 10.74 μm, characterised by redeposited spherical debris, shallow cavities, and a surface texture of 2.688 μm. The layer's hydrophilic nature is confirmed by a minimum contact angle of 47.68°. Taguchi analysis indicates that the machining rate is optimised at an HA powder concentration of 16 g/l, with peak current and HA powder concentration being the most influential parameters affecting resolidified layer thickness, surface texture, and wetting angle. The research intends to motivate SS 316L medical device manufacturers to implement the HA-assisted EDM process for bioimplant's dual machining and coating. [ABSTRACT FROM AUTHOR]

The titanium scaffolds and surface-porous implants are manufactured by fast and cheap additive methods such as selective laser melting (SLM). The obtained irregularity and relative biological inertness of the titanium need proper surface modification. This research is aimed at forming bioactive multicomponent oxide coatings by micro-arc oxidation (MAO) at different process parameters on the selective laser-melted Ti13Zr13Nb alloy. The MAO process was carried out in a base solution containing 0.15 mol/L Ca and 0.1 mol/L GP, with different amounts of metasilicate added under two different applied voltages. Scanning electron microscopy, atomic force microscopy, X-ray electron diffraction spectroscopy, nanomechanical and nano scratch tests, water contact angle measurements, phosphate deposition observed in long-term immersion tests, and biological LDH and MTT assays were performed. The results showed that the coating microstructure, morphology, and properties were significantly dependent on process parameters. In particular, the metasilicate addition and its rising content in the electrolyte resulted in the higher development of the surface followed by better viability of osteoblasts at no necrosis, with no negative change in the other parameters, usually close to those obtained on silicon-free coatings. The obtained results prove that the addition of silicon to the electrolyte at the partial expense of calcium can be favorable for long-term titanium implants made by selective laser melting. [Display omitted] [ABSTRACT FROM AUTHOR]

Fused-silica-based microlens array (MLA) has excellent stability in the harsh environment. However, it is still a challenge to efficiently prepare superhydrophobic quasi-periodic MLA and keep the optical performance of the microlens. In this paper, we proposed spatial modulated picosecond laser parallel processing method to prepare a superhydrophobic quasi-periodic MLA on fused silica. By using a spatial light modulator, the picosecond laser was shaped to multi-focal spots and line-shape beam, respectively, which improved the fabrication efficiency. The line-shape beam was the key to induce micro-nanostructures on the smooth MLA and keep the optical performance of the microlens. The results showed that the surface roughness of the microlens region was less than 100 nm. Combing with shaping picosecond laser processing and chemical treatment, the superhydrophobic MLAs showed the excellent anti-fogging and self-cleaning properties. The average contact angle of the superhydrophobic MLAs was 162.3°. The superhydrophobic MLA showed low adhesion to water droplet (<10 μN) and low contact angle hysteresis (2.1° ± 0.7°). We believe shaping picosecond laser parallel processing method is a flexible and low-cost approach to prepare superhydrophobic micro-optical elements on fused silica. [ABSTRACT FROM AUTHOR]

Dental implants fabricated from titanium have several limitations and therefore, alternative materials that fulfil the criteria of successful dental implant (bioactivity and anti-bacterial activity) need to be considered. Polyether ether ketone (PEEK) has been suggested to replace titanium implants. However, this material needs surface modification to meet the appropriate criteria. A nano-sized zirconium phosphate/GO (nZrP/GO) composite coating was prepared to improve PEEK's biological qualities. Polished and cleaned PEEK discs were coated with the composite of nZrP doped with 1.25 wt% GO by the soft-template method. To analyze the composite coating, X-ray, atomic force microscopy, and field emission scanning electron microscopy-energy dispersive spectroscopy were used. The adhesion of the coating to PEEK was measured by adhesive tape test. By measuring the optical contact angle, the coated and non-coated samples' differences in wettability were evaluated. Antimicrobial activity was evaluated against S. aureus and E. coli and cytotoxicity tested employing gingival fibroblasts and osteoblast-like cells. The nZrP/GO composite coating was 23.45 µm thick, was irregular and attached strongly to the PEEK surface. Following coating, the water contact angle dropped to 34° and surface roughness to 13 nm. The coating reduced the count of bacteria two-fold and was non-cytotoxic to mammalian osteoblast-like cells and fibroblasts. A precipitation of nano-calcium-deficient apatite was observed on the surface of the nZrP/GO coating following a 28-day immersion in SBF. PEEK-coated with nZr/GO coating is a good candidate as dental implant. • nZrP/GO converts PEEK surface from bionert to a bioactive surface. • Addition of GO into nZrP potentiates its anti-bacterial activity. • PEEK implant coated with nZrP/GO is not cytotoxic to mammalian cells. • nZrP/GO increases surface wettability of PEEK implant. • Addition of GO has no effect on adhesion of nZrP coating to PEEK surface. [ABSTRACT FROM AUTHOR]

This study explores the use of air-fed atmospheric pressure plasma jets (APPJs) as a pre-joining treatment for 3D carbon fiber-reinforced carbon matrix composites (C/C) with the aim of both creating a textured surface that resembles a brush structure and improving the joint strength. The effects of various treatment time lengths on the mass loss, etching depth, and surface texture were investigated using SEM and confocal microscopy. An optimal process time of 30 s was selected, while keeping the other process parameters fixed (air flow of 1750 l/h and nozzle-sample distance of 5 mm). Wetting tests were conducted at 1000 °C, on both untreated and pre-treated C/C surfaces by means of liquid TiCuNi brazing alloy, and low contact angles of about 20° were measured. C/C–TiCuNi–C/C and C/C–TiCuNi–Cu joints were then produced, and their interfacial reactivity was evaluated. The apparent shear strength measured for the APPJ-treated C/C–Cu joints was 140 % higher than the value recorded for the untreated joints, thus confirming the effectiveness of the treatment. Even though a further investigation is needed in which an optimization of the process parameters should be included, this preliminary study has revealed the viability of APPJ as a promising technique to enhance the bonding of C/C composites in dissimilar assemblies and to improve the joint quality. [ABSTRACT FROM AUTHOR]

To further improve the basic theory of blast furnace hydrogen-rich smelting and provide a reference for blast furnace hydrogen-rich production, the influences of different conditions on the contact angle and carburization amount of the iron‒coke interface were measured using iron‒coke interface reaction experiments, and the erosion of the three-dimensional morphology of the coke surface by the iron‒coke interface reaction process was analysed. As the degree of coke dissolution increased, the iron‒coke interface contact angle increased, and the amount of carburization decreased. The change in the interface contact angle and carburization amount between iron and coke after reacting with H 2 O was greater than that after reacting with CO 2 , and the interface reaction rate constant and carburization amount were lower for H 2 O than CO 2. When the reaction time increased by 1 min, the differences in the contact angle and carburization amount between the two atmospheres increased by 0.12° and 0.013%, respectively. This improved the permeability of the metal iron for its penetration in the coke layer and was beneficial for stable production. An increase in the reaction temperature and a decrease in the initial carbon mass fraction (w (C)) of metallic iron both increased the carburization rate at the iron‒coke interface, reduced the equilibrium contact angle, improved wettability, and caused severe erosion of the carbon matrix structure on the coke surface. When the temperature exceeded 1673 K, the metal iron could undergo a violent carburization process with coke surface 3, resulting in a wetting phenomenon. The initial w (C) of metallic iron increased by 1%, and the equilibrium contact angle of the iron‒coke interface increased by approximately 3.32°. [Display omitted] • Analyse the interface behavior between iron and coke after reacting with H 2 O and CO 2. • The surface of coke after reacting with H 2 O has poorer wettability with iron. • The effect of various factors on iron-coke wettability was quantitatively analysed. [ABSTRACT FROM AUTHOR]

This study aimed to use a carboxybetaine methacrylate (CBMA) copolymer solution to surface treat 3D printed clear aligners at different fabrication stages, to impart antifouling properties, and assess the surface treatment at various fabrication stages' impact on physico-mechanical characteristics. Surface treatments using a blend of 2-hydroxyethyl methacrylate (HEMA) and CBMA, termed CCS, were performed at various stages of 3D printed clear aligner fabrication. Experimental groups, CB1, CB2, and CB3, were determined by the stage of surface treatment during post-processing. CB1, CB2, and CB3 received treatment before post-curing, after post-curing, and after post-processing, respectively. Untreated samples served as controls. Physical and mechanical properties were assessed through tensile testing, Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and UV-Vis spectroscopy. The surface was further characterized through scanning electron microscopy and contact angle measurements. The cytotoxicity was assessed with 7-day elution and agar diffusion assays. Lastly, bacterial biofilm resistance was evaluated using confocal laser scanning microscopy. Crystal violet assay was performed using Streptococcus mutans. Surface treatment during CB1 stage exerted the most significantly unfavorable influence on properties of the 3D printed aligner resin. CB2 samples showed the maximum preservation of translucency even after 7-day aging. CB2 and CB3 phases showed enhanced hydrophilicity of sample surfaces with reduced adhesion of multispecies biofilm and S. mutans. Application of CCS surface treatment immediately after post-curing (CB2) can enhance the biofilm resistance of 3D printed clear aligners while maintaining high fidelity to optical translucency and constituent mechanical properties. [ABSTRACT FROM AUTHOR]

Enhancing chemical mechanical polishing (CMP) performance is the key to improving the surface quality and processing cost of silicon carbide (SiC). However, traditional SiO 2 abrasive fails to meet the material removal rate (MRR) requirement for SiC processing. In order to solve this problem, we use chemical deposition method to coat MnO 2 on the surface of SiO 2 to enhance CMP performance. A series of SiO 2 @MnO 2 composite abrasives (the coating mass fraction of MnO 2 on the surface of SiO 2 is 0, 0.03 wt%, 0.05 wt%, 0.07 wt%, 0.10 wt%, respectively) are synthesized and characterized. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and the size distribution analyses confirm that the composite abrasive possesses a core-shell structure, wherein the core is composed of SiO 2 while the shell consists of MnO 2. The results of CMP experiments demonstrate that the MRR of SiO 2 @MnO 2 (0.05 wt%) can reach 403 nm/h, which is 220% higher than that traditional SiO 2 abrasive, effectively resolving the limitation of MRR in previous literature. Additionally, the surface roughness (Sa) is reduced to 0.62 nm (measuring area: 500 μm × 500 μm). X-ray photoelectron spectroscopy analysis, contact angle test and dynamic friction test are used to further explore the removal mechanism of composite abrasives in SiC CMP. As a result, Mn–O–Si bond is formed by chemical interaction between the slurry including SiO 2 @MnO 2 composite abrasive and SiC substrate, which weakens Si–C bond of SiC surface. The dynamic friction coefficient of the composite abrasive on SiC substrate is enhanced, implying that the coating of MnO 2 also increases the contact sites and mechanical effect between the abrasive and SiC. Under the synergistic action of chemical and mechanical effects, the MRR of SiC is improved, and a better flatness is obtained. [ABSTRACT FROM AUTHOR]

Challenges exist regarding the bonding efficiency of polyaryletherketone (PAEK), a high-performance thermoplastic, attributed to its chemical inertness and hydrophobic surface, hindering effective bonding with resin-matrix cement. This research explored the impact of handheld nonthermal plasma (HNP), under varying operational parameters, on PAEK surface wettability and changes in bonding performance with cement. Three types of disc-shaped PEAK specimens were prepared, with surface treatments categorized as grinding, airborne-particle abrasion (APB), and HNP. Surface wettability was analyzed using a contact angle analyzer (n = 10). Specimens were bonded with resin cement and subjected to artificial aging tests: distilled water bath (NA), thermocycling, and highly accelerated stress tests (n = 10 for each test). Shear bond strength (SBS) was measured, failure modes were analyzed, and statistical analyses were conducted. The HNP markedly improved PAEK surface wettability, achieving superhydrophilicity (P < 0.05). This effect intensified with extended operation times (30 or 60 s) and reduced elapsed times (<30 s). HNP-treated PAEK exhibited higher SBS than APB (P < 0.05) and maintained bonding durability after artificial aging, particularly in ketone-enriched variants. Failure analysis revealed predominantly adhesive failure under APB–NA treatment, mixture failures under HNP–NA treatment and postaging, but no cohesive failure. The HNP device benefits dental settings by transforming the PAEK surface into superhydrophilic properties, thereby improving PAEK–cement bonding. It significantly enhances bond durability within 30 s of operation and after a 30 s elapsed period. It is noteworthy that ketone-enriched PAEK demonstrates markedly improved bonding performance. [ABSTRACT FROM AUTHOR]

This study employed Micro X-ray computed tomography (Micro-CT) to reconstruct the gas diffusion layer (GDL) in proton exchange membrane fuel cells (PEMFCs) and used lattice Boltzmann method (LBM) simulations to investigate the dynamic behavior of liquid water in the multiscale space of the GDL and gas channel (GC). The results showed that the transport of liquid water from GDL to GC through the interface of GDL-land and GDL-GC were divided into four stages: large pore filling, through-plane breakthrough, in-plane diffusion, and rapid transport into GC. The wettability of GC wall and GDL affects the transport and distribution of liquid water. When the contact angle on the GC wall was less than 90°, it promoted liquid water transport to the top GC wall, resulting in faster internal flow formation. Conversely, contact angles exceeding 90° caused liquid water to break through the GDL-GC interface from pores away from the GC wall. When the contact angle of the GDL was in the range of 110°–150°, both excessively large and excessively small contact angles hindered water transport and management. Maintaining the contact angle of the GDL around 130° enhanced the breakthrough path and transport speed of liquid water into the GC, and it also reduces localized liquid water accumulation. [Display omitted] • The real structure of GDL was reconstructed by Micro-CT scanning. • The dynamic behavior of liquid water in GDL-GC and their interface is studied by LBM. • The wettability of GC and GDL affects the transport and distribution of liquid water. [ABSTRACT FROM AUTHOR]

Underground hydrogen storage has emerged as a strategy to address the challenge of large-scale, long-term, and economically viable hydrogen preservation, fulfilling energy demands and balancing supply intermittency in renewable energy systems. This paper seeks to enrich the discourse on sensitivity analyses concerning underground hydrogen storage processes by reviewing the influence of wettability. In this work, we present our review of wettability in geological formation for hydrogen storage starting with sandstone formations, carbonates, shale, and finally basalt. Results show that published water/hydrogen contact angle measurements indicate strong water-wet to intermediate water-wet conditions at ambient conditions for most formations. • Sandstone and basalt show consistent water-wet state at various conditions, thus considered ideal for hydrogen storage. • Microbial activity alters wettability and increases contact angle, posing risks for certain lithologies like carbonate. • Increased organic matter in carbonate and shale increases contact angle measurements, especially at high pressure. [ABSTRACT FROM AUTHOR]

The gas diffusion layer (GDL) plays an important role in proton exchange membrane fuel cells (PEMFC) to support the catalytic layer, collect the current, conduct the gas and discharge the reaction product water. Titanium (Ti) can be one of the choices of GDL materials due to its high strength, low density and excellent corrosion resistance. Therefore, this paper investigated Ti substrate material for GDL and comparatively analyzed the changes in the contact angle of the GDL before and after hydrophobic treatment, analyzed the changes in the performance of the cell after different treatment processes, and measured the effect of compression force on the contact resistance of the cell. The results show that, after the selection of Ti felt as the substrate and the carbon plating process, the contact angle of the substrate layer and the microporous layer increased significantly, and the hydrophobicity of the GDL surface improved after carbon plating. The contact resistance of the Ti felt substrate was significantly reduced after carbon plating and was even lower than that of the C–H-060 substrate. Considering the importance of the hydrophobicity of GDL, acetylene black microporous layer coating is also needed to increase the contact angle of the GDL interface and improve the hydrophobicity of GDL. The hydrophobic treatment of MPL using Ti felt as the substrate can significantly improve the output performance of the cell at high current density, avoid flooding inside the cell, and increase the current density operating range of the cell. • The contact angle of Ti-GDL before and after hydrophobic treatment was studied. • The performance of Ti-GDL cell after different treatment processes were compared. • The effect of compression force on the contact resistance was analyzed. • The feasibility of Ti as a substrate for GDL in PEMFC was analyzed. [ABSTRACT FROM AUTHOR]

This work aims to develop environmentally friendly silane coating reinforced with a hybrid pigment to protect mild steel against corrosion in a saline environment. Fourier-transform infrared (FT-IR) spectroscopy, contact angle (CA) measurement, field emission scanning electron microscopy (FE-SEM), and energy dispersive spectroscopy (EDS) were used to study the coating structure and its protective mechanisms. The presence of hybrid pigment led to the conversion of more Si–OH groups into Si–O–Si groups during condensation process increasing the cross-linking density of silane; the enhanced cross-linking yields the coating with lower defects and stronger adhesion to substrate and so improved barrier and anti-corrosion properties. The EIS test showed that the charge transfer resistance (R ct) for the sample coated with hybrid sol-gel silane increases up to 40 % for all immersion times after the incorporation of the hybrid pigment into the coating matrix. The polarization test showed that the corrosion current density (i corr) value decreases from 1.40 to 0.56 μA/cm2 after 120 h of exposure to the saline solution when the hybrid pigment is added to the coating matrix. These results demonstrate the inhibitive action of the hybrid pigment enhancing the protective performance of the sol-gel silane coating. [ABSTRACT FROM AUTHOR]

This study presents an approach for fabricating super hydrophilic self-cleaning anti-fog micro-nano structures on silicon-coated glass utilizing a laser marking machine. The surface features a periodic microstructure interspersed with irregular nanoparticles, which contribute to its durable superhydrophilicity, maintaining a 0° contact angle for up to one year—the longest duration recorded to date. Moreover, it sustained its anti-fogging and self-cleaning abilities for 467 days, establishing the lengthiest duration for maintaining a 0° contact angle and retaining anti-fogging performance without visible deterioration. The sample also retained excellent anti-fogging and self-cleaning properties even after 43 days of outdoor exposure. Such remarkable performance was attributed not only to surface chemistry and roughness but also to the presence of dense, uniform, and minimally varying microstructures. The unique structure also enhanced the solar spectrum (AM 1.5) weighted average transmission by 3.84 % over control glass in the wavelength range of 400–1100 nm. It holds promising potential for use in automotive rearview mirrors, windows, and solar cells. [ABSTRACT FROM AUTHOR]

In this study, the mechanical behavior and biocompatibility of plasma electrolytic oxidation (PEO)-coated Mg–Zn–Ca alloy specimens were investigated. The coatings were synthesized by incorporating KMnO 4 and Mn 3 O 4 nanoparticles into an electrolytic solution. An indentation test revealed a significant increase in the reduced elastic modulus of the PEO coatings with incorporated Mn 3 O 4 under various loads. This increase was attributed to the higher coating thickness and reduced porosity achieved by the addition of Mn-based additives to the electrolyte. The composite PEO coatings prepared with Mn 3 O 4 nanoparticles exhibited a more pronounced reduction in elastic modulus under pressure. Wettability tests showed that the prepared coatings maintained their hydrophilic nature with water contact angles in the range of 25–63°. The presence of Mn 3 O 4 in the PEO coatings provided a conducive environment for cell viability. The enhanced biocompatibility of the composite coatings achieved by incorporating KMnO 4 into the electrolyte was particularly noteworthy. This improvement was attributed to the controlled release of Mn ions, which generates a microenvironment that favors cellular activities. The study showed that incorporating Mn 3 O 4 into PEO coatings enhances mechanical properties, preserves hydrophilicity, and improves biocompatibility, thus indicating its potential for orthopedic implant applications. [ABSTRACT FROM AUTHOR]

The presented work explores detail information about surface modification of BNNTs with ZrO 2 through isothermal hydrolysis process for reducing its hydrophobic property and enhancing the wettability as BNNTs possess hydrophobicity & poor wettability in its raw form as it agglomerates during fabrication of composites, ultimately prohibits usage of BNNTs as a prime reinforced material and for other utilization. HRTEM, EDX, E.M confirmed thin coating layer of ZrO 2 whereas X-ray diffraction and FE-SEM determined the morphological structure of BNNTs in its raw form comparing with properties of BNNTs@ZrO 2. Contact angle test displays increased wettability of synthesised BNNTs where Zeta Potential provides upgraded stability and dispersibility of coated BNNTs in aqueous medium. Confirmation of coating, improved surface architecture and chemical properties of coated BNNTs than non-treated BNNTs is observed via FTIR. BNNTs@ ZrO 2 showing thermally stable and constant throughout temperature beyond 800 °C through TGA. Present study describes the features of BNNTs and BNNTs@ZrO 2 enriching morphological and thermal characteristics followed by confirmation of coating layer through isothermal hydrolysis process, improvement in wettability and hydrophobicity for further future approach towards reinforcement in MMCs, in a nut shell very effectively applicable in aerospace and automobile industrial utilization. [ABSTRACT FROM AUTHOR]

• Preferred nucleation type at different water vapor contents (0.1 – 1000 ppmv) were revealed. • Different frosting pathways representing three typical operating conditions were discussed. • Trace water vapor nucleation requires a greater subcooling degree, has a smaller nucleation radius. • Reducing subcooling degree and increasing contact angle are more effective anti-frosting methods. In certain extreme conditions characterized by ultra-low water vapor content and ultra-low temperatures (e.g. cryogenic wind tunnel), trace water vapor frosting can also pose significant hazards. Considering the crucial role of initial nucleation on subsequent frosting processes, this study firstly investigated and compared the nucleation characteristics of frosting at different water vapor contents (0.1−1000 ppmv) from humid air to trace water vapor based on classical nucleation theory. The preferred nucleation phase diagrams and critical nucleation conditions were analyzed. Sensitivity of the nucleation mass transfer rate, as well as the frosting pathways were further identified. Results show that the nucleation characteristics of trace water vapor frosting (<100 ppmv) is significantly different from that of humid air frosting (>1000 ppmv). Trace water vapor frosting is more inclined towards desublimation nucleation due to its lower nucleation temperature and larger critical contact angle. The critical contact angles for 1000 ppmv, 100 ppmv and 0.1 ppmv are 49°, 75° and 120°, respectively. Furthermore, trace water vapor nucleation requires a greater subcooling degree, has a smaller critical nucleation radius, and is highly sensitive to surface contact angle and further-subcooling degree. At a surface contact angle of 120°, the nucleation subcooling degree of 0.1 ppmv is 2.9 K greater than that of 1000 ppmv. This study helps understanding the nucleation characteristics under different water vapor content conditions, which indicates that reducing subcooling degree and increasing contact angle are more effective anti-frosting methods than reducing water vapor content for trace water vapor frosting. [ABSTRACT FROM AUTHOR]

As container for the photovoltaic (PV) Si growth, fused silica crucible can only be used once owing to crystallization breakage, which inevitably reduces the quality and yield of Si. To develop re-useable crucible, Si 3 N 4 ceramics were successfully fabricated using novel BaSiO 3 (0-8 wt%) as sintering aid. Higher BaSiO 3 content promotes the densification and sintering of Si 3 N 4 ceramic. Then, the wetting/infiltration behaviors of Si/Si 3 N 4 binary systems were systematically investigated by sessile drop test and microstructural analysis technology. With 8 wt% BaSiO 3 introduction, the Si 3 N 4 ceramic displayed larger contact angle of Si drop and excellent Si infiltration resistance, which was determined by de-oxidation rate. Moreover, three type of infiltrations, including infiltrations under Si drop and beyond Si drop (on/under substrate surface), were found and systematically analyzed. In this work, novel sintering aid (BaSiO 3) was developed for Si 3 N 4 ceramic fabrication at relatively lower sintering temperature. Additionally, the data of wetting/infiltration behavior for Si/Si 3 N 4 binary system can be used to guide the application of Si 3 N 4 crucible in PV Si manufacture. [ABSTRACT FROM AUTHOR]

Graphite-based composite materials have emerged as a crucial alternative to traditional flake graphite for optimizing the performance of Al 2 O 3 -SiC-C (ASC) castables after decarburization. In this paper, high wetting SiC@C composites powder was prepared via a sol-gel method combined with a carbothermal reduction reaction, and its effect on the oxidation behavior of ASC castables is explored. The results showed that SiC@C composites was synthesized under microwave conditions at 1000 °C, forming a structure where SiC whiskers are coated. And its contact angle with water decreases from 107° to 35°. Upon incorporation into ASC castables, the SiC whiskers within the sample continued to grow and develop with increasing addition of graphite-based composite materials. At a 2 wt% addition, the SiC whiskers began to form a cylindrical structure. Simultaneously, both the cold crushing strength and cold modulus of rupture exhibited a gradual increase. At the optimal 2 wt% addition, these values reached their maximum, 79.5 MPa and 11.4 MPa, respectively. The substitution of graphite-based composite materials also conferred good oxidation resistance to the ASC samples. Under oxidizing atmosphere conditions, the SiC whiskers on the composite material's surface facilitated the formation of a SiO 2 coating layer, which impeded the contact between oxygen and graphite, thereby enhancing the oxidation resistance of the material. Consequently, the oxidation index was reduced from 75.58 % to 42.71 %. [ABSTRACT FROM AUTHOR]

The wettability properties of the porous components in a proton exchange membrane fuel cell (PEMFC) are a key factor in relation with the water management issue and a key information in order to predict the water retention curve, a crucial input data for the macro-homogeneous models. In this work, we propose an approach to construct the contact angle distribution in three-dimensional digital images of the cathode catalyst layer. Various reconstruction scales are considered, from the platinum particle scale to the pore scale and the scale of sub-blocks in the CCL. This leads to effective contact angle distributions depending on the scale of interest. The approach also allows to investigate the link between the pore size and the effective contact angle at the pore scale. The combined information of the pore size and the effective contact angle for each pore is used to get insights into the water retention curve. • Contact angle distributions are computed in the secondary pore space. • The impact of the ionomer coating thickness spatial variation is considered. • The effective contact angle is determined for each pore. • The water retention curve is obtained. [ABSTRACT FROM AUTHOR]

Flake graphite (FG) poses challenges for incorporation into castables due to its hydrophobic nature. In this paper, a strategy combining liquid-phase shear exfoliation (LPSE) with hydrothermal processing was proposed to produce hydrophilic graphene nanosheet/AlOOH nanofiber (GN/ANF) composite powders to address this issue. Under optimal shear exfoliation conditions, the yield of graphene nanosheets (GNs) reached up to 57%. Following a straightforward hydrothermal treatment, the water contact angle of as-prepared GN/ANF composite powders decreased to 53.1°, compared to 103.6° of the original FG. Benefiting from the hydrophilic properties of the composite powders and the homogeneous dispersion of GNs in MgO castables, the sample containing 0.5 wt% GNs exhibited better high-temperature performance than its counterparts. Relative to the control specimen, the slag corrosion index of the sample containing 0.5 wt% GNs decreased from 0.60 to 0.13, while the thermal shock resistance increased by approximately 2.8 times. • Using the liquid-phase shear exfoliation method, the yield of graphene nanosheets reaches 57.02%. • After hydrothermal treatment, the water contact angle of graphene nanosheet/AlOOH nanofiber composite powders decreases from 103.6° to 53.1°. • Adding 0.5 wt% graphene nanosheets to MgO castables reduces the slag corrosion index from 0.60 to 0.13 and increases thermal shock resistance by about 2.8 times. [ABSTRACT FROM AUTHOR]

Volcanic ash dispersed in the air adheres to thermal barrier coatings (TBCs) on the hot section components of gas turbines, posing a severe threat to aviation safety. Here, we report a novel strategy inspired by lotus leaf for mitigating the molten volcanic ash adhesion and corrosion. A hierarchical micro-nano structure composed of arrayed micro-conoids and numerous nanoparticles were constructed on the surface of NdYbZr 2 O 7 ceramic pellet by ultrafast laser direct writing technology, whose morphology could be changed by optimizing the processing parameters. The laser-ablated pellet exhibits larger contact angle of molten volcanic ash than the original one, revealing an enhanced resistance repelling volcanic ash. This phenomenon is primarily attributed to the air trapped in the micro-grooves, together with these nanoparticles. Note that the evolution of viscous force and capillary force with time accelerates the transition of molten volcanic ash from the Cassie state to the Wenzel state and reduces its contact angle. Also, this structure effectively inhibits the infiltration of molten volcanic ash by rapidly developing a reaction layer. These findings are an important step toward the design and development of next-generation silicate ash-repellent TBCs. [ABSTRACT FROM AUTHOR]

Titanium and its alloys have been recognized as biocompatible materials since decades although these materials can at times show wear, corrosion and thrombosis leading to various health complications. Surface coating has been found to be one of the effective techniques to overcome this issue in-vitro as well as in-vivo. In this paper, thin film coating of zirconia (ZrO 2) on Ti6Al4V is reported using pulsed laser deposition (PLD) technique at elevated substrate temperatures ranging from room temperature to 800 °C (TiZr800). The morphology, composition, wettability and average surface roughness of the samples were analyzed by scanning electron microscope, Raman spectrometer, water contact angle (WCA) and profilometer, respectively. Adhesion between film and substrate was qualified using Elcometer. The tribological studies were performed in ball-on-disc against ZrO 2 counterpart, the electrochemical potential analysis was done in simulated body fluid to replicate body environment and the hemocompatibility test was evaluated on the basis of human whole blood adsorption and distribution of Red Blood Cells (RBCs) on the samples. The results revealed an increase in WCA and film adhesion with increased substrate temperature. At 800 °C, formation of zirconium carbide, a relatively harder material, was observed due to diffusion of substrate carbon into ZrO 2 film, as confirmed by the Raman analysis. In comparison to pristine, TiZr800 sample showed a reduction in wear rate from 3.5 × 10−3 mm3/Nm to 1.1 × 10−3 mm3/Nm indicating improved resistance of the sample against abrasive wear. Further, drop in I corr from 4.96 × 10−7 A/cm2 to 2.75 × 10−7 A/cm2 resulted in a 44 % increase in corrosion protective efficiency of the sample coated at 800 °C. Additionally, a 4.5 fold increase in RBC counts was observed on TiZr800 sample. Therefore, it is inferred that while ZrO 2 coating can improve overall surface properties of Ti–6Al–4V, additional benefits can be obtained by performing PLD at higher substrate temperatures, more so when the temperature is such as to promote formation of ZrC in the coating. [ABSTRACT FROM AUTHOR]

Recently, superhydrophobic magnesium (Mg) alloys are extensively investigated due to their promising applications in corrosion protection and resistance to bacterial adhesion. However, superhydrophobic surfaces may not be conducive to the osteogenic effect of the coated Mg alloys, which limits their clinical application as implants. Herein, the lauric acid (LA)/MoS 2 /Hydroxyapatite (HA) (LMH) superhydrophobic composite coatings were synthesized on AZ31B Mg alloy by hydrothermal process and hydrophobic treatment. The coated Mg alloy had favorable superhydrophobicity, as evidenced by a contact angle measurement of approximately 151.8°. After 3 min of ultrasonic treatment, the contact angle of the coated Mg alloy decreased from 151.8° to 63.5°, which was attribute to the sonothermal effect that changes the surface energy of the coating, hereby removing the air layer at the superhydrophobic interface. Compared to the bare Mg alloy, the electrochemical impedance of the LMH-2.0 superhydrophobic composite coating increased by two orders of magnitude to 89.611 ± 0.593 kΩ cm2. In vitro antibacterial tests showed that the antibacterial efficiency of LMH-2.0 superhydrophobic coating against both S. aureus and E. coli is more than 99% with the assistance of ultrasonic. Meanwhile, the cell fluorescence staining experiments exhibited that the superhydrophobic coating featuring convertible wettability exhibited promising early cell growth and adhesion. The superhydrophobic coatings with wettability transition on magnesium alloys are expected to be ideal modification coatings for degradable implant materials. [ABSTRACT FROM AUTHOR]

This study aimed to assess BioRoot RCS (BR) incorporating liposomal chlorhexidine digluconate (CHX) for its antibacterial activity, drug release capacity, and physicochemical properties. Drug release of CHX liposomal formulations in combination with BR was evaluated spectrophotometrically and through mathematical release models for 30 days. A selected combination was evaluated for antimicrobial properties against Enterococcus faecalis biofilm growth on human dentin. Cytotoxicity was assessed following the ISO 10993-5:2019 standard on days 1, 3, and 7. Physicochemical properties were evaluated through setting time, Fourier transform infrared spectroscopy, solubility, contact angle, and film thickness. From BR, liposomal CHX released up to 7-fold higher CHX than CHX solution (P <.05), following a triphasic drug release pattern compared to the CHX solution, which followed a quasi-Fickian diffusion. BR combined with a selected liposomal CHX completely inhibited E. faecalis biofilm growth compared to the combination of BR with CHX solution and the control group (P <.05). Liposomal CHX decreased the contact angle (P <.05) and solubility but increased cytotoxicity (P <.05) of BR, staying above the ISO threshold. None of the other physicochemical characteristics tested differed from BR (P >.05). This liposomal formulation improved CHX release from BR, enhancing the antibacterial effectiveness. It presents a promising approach for local antibiofilm therapy in endodontics without substantially altering the physicochemical characteristics of BR. [ABSTRACT FROM AUTHOR]

The corrosion behavior of novel MgO–Mg 1.08 Al 1.84 Ti 0.08 O 4 refractories was investigated as a potential replacement for traditional MgO–MgAl 2 O 4 refractories as the inner lining of RH snorkels. The incorporation of Mg 1.08 Al 1.84 Ti 0.08 O 4 fine powder with dense microstructure resulted in superior densification and mechanical strength compared to traditional MgO–MgAl 2 O 4 refractories. The novel MgO–Mg 1.08 Al 1.84 Ti 0.08 O 4 refractories significantly enhanced their corrosion resistance, due to the reduction in porosity and pore diameter, as well as the increase in pore complexity and contact angle. These factors effectively impeded the penetration of RH slag. Additionally, the presence of Mg 1.08 Al 1.84 Ti 0.08 O 4 in contact with RH slag formed a more complex (Mg, Fe)(Al, Ti) 2 O 4 spinel solid solution, which exhibited strong Fe element absorption ability. Thus, this decreased the Fe concentration in the RH slag, resulting in an increase in liquid slag viscosity and enhancing the slag penetration resistance of MgO–Mg 1.08 Al 1.84 Ti 0.08 O 4 refractories. The microstructure of the MgO–Mg 1.08 Al 1.84 Ti 0.08 O 4 refractories featured an isolated distribution of Ca 2 SiO 4 phase, which suggested fewer channels for liquid RH slag to penetrate the refractory materials. According to Factsage 6.2 thermodynamic simulation, the dissolution of Mg 1.08 Al 1.84 Ti 0.08 O 4 into liquid slag was lower compared to the sintered MgAl 2 O 4 , which was advantageous for resisting the dissolution of refractory materials into liquid slag. [ABSTRACT FROM AUTHOR]

In this work we show how the addition of a third element, namely Fe or Ni, influences the interfacial behaviour of liquid TiAl alloys on polycrystalline alumina. Wetting of these alloys was studied by the sessile drop method at 1500 °C and the interfacial microstructures were characterised to determine the relation between the contact angle and the interfacial reaction with the aid of the relevant phase diagrams. The equiatomic TiAl intermetallic wetted the alumina substrate forming a contact angle of 60°. On the other hand, increasing concentrations of Fe and Ni were found to improve the wetting behaviour of ternary TiAl-X alloys: for third-element atomic concentrations of 5 at. %, contact angles decreased to 32° and 29° by adding Fe and Ni, respectively. Neither reactive-formed interlayers nor newly formed phases were observed for any binary or ternary composition as confirmed by thermodynamic calculations. A slight dissolution of the ceramic occurred during liquid/solid contact and became more evident with the increase of concentration of the third element. The introduction of oxygen into the melt provided by the dissolution of alumina improved the wetting behaviour. [Display omitted] [ABSTRACT FROM AUTHOR]

In the field of conservative dentistry and endodontics, mineral trioxide aggregate (MTA), commonly used, possesses advantages such as biocompatibility, antimicrobial properties and osteogenic potential. This study investigated the feasibility of utilizing membrane form mineral trioxide aggregate (MTA) as a barrier membrane in guided bone regeneration (GBR) procedures. Membranes were electrospun from three different formulations: 15 w/v% Polycaprolactone (PCL), 13 w/v% PCL + 2 w/v% MTA (2MTA), and 11 w/v% PCL + 4 w/v% MTA (4MTA). Physicochemical and mechanical properties of the electrospun membrane were compared, encompassing parameters such as surface morphology, fiber diameter distribution, chemical composition, phase identification, tensile stress, pH variation, and water contact angle. Moreover, the antimicrobial properties against of the electrospun membranes were assessed through direct exposure to streptococcus aureus (S. aureus) and candida albicans (C. albicans). Additionally, on the 7th day, biocompatibility and cell attachment were investigated with respect to L929 (fibroblast) and MC3T3 (pre-osteoblast) cells. Inhibition of L929 cell infiltration and the expression of osteogenic related genes including osteocalcin (OCN), alkaline phosphatase (ALP), and runt related transcription factor 2 (RUNX2) in MC3T3 cells on 7th and 14th days were also investigated. PCL, 2MTA, and 4MTA exhibited no statistically differences in fiber diameter distribution and tensile stress. However, as the MTA content increased, wettability and pH also increased. Due to the elevated pH, 4MTA demonstrated the lowest viability S.aureus and C.albicans. All membranes were highly biocompatibility and promoted cell attachment, while effectively preventing L929 cell infiltration. Lastly 4MTA showed increase in OCN, ALP, and RUNX2 expression on both 7th and 14th day. The membrane form MTA possessed characteristics essential for a novel barrier membrane. [ABSTRACT FROM AUTHOR]

The time and temperature of the dispersive shear process of catalyst inks have a great influence on the agglomerate structure of the ink and the rheological properties of the ink. In this paper, three different catalyst inks were prepared at 20 °C, 30 °C and 40 °C, and tested using characterization such as rheological techniques, zeta (ξ) potential, and particle size measurements. As the temperature rises, the median particle size inside the ink at the end of shear was 400, 308.05 and 157.3 nm, and the zeta potential was −37, −33 and −25 mV, with a decrease in viscosity and a deterioration in thixotropy. The catalyst layers prepared from inks dispersed at different temperatures had the smallest cracks and the flattest surface at 30 °C, and the largest cracks, the largest contact angle, the roughest surface, and the poorest polarization properties at 40 °C. Through the comprehensive analysis of the experimental data, the fragmentation and reorganization processes of agglomerates during the internal dispersion of catalyst ink were revealed from the perspectives of time scale and temperature variation, respectively. This study provides an experimental basis for a deeper understanding of the dispersion performance of catalyst ink at different temperatures. • The variation of internal temperature of catalyst ink with shear time was studied. • The effect of shear time on catalyst inks was studied. • The effect of dispersion temperature on catalyst inks was investigated. • The relationship between rheology and catalyst layer structure was proved. [ABSTRACT FROM AUTHOR]

NASA seeks to develop technologies to mitigate dust accumulation from planetary surfaces on robotic and human systems hardware during planned space exploration missions. With a return to the Lunar surface, lunar dust threatens the durability and reusability of components and vehicles due to its fine, jagged morphology and highly abrasive nature. Lunar dust consists of particles less than 60 μm in size that are chemically reactive, electrostatically and sometimes magnetically charged. Unique materials and technologies that reduce or mitigate lunar dust adhesion will be critical to support long duration missions and eventual sustained presence on the lunar surface. The goal of this work was to prepare dust resistant, space durable polymer films to satisfy dust accumulation mitigation needs for future NASA missions. In this regard, several graphene coated polyimide thin films have been developed with surface resistivity properties in the range of 103 Ω/sq to 1011 Ω/sq and evaluated for their dust adhesion performance. Raman spectroscopy was used to characterize and assess the quality of graphene ink coated sheets while surface resistivity measurements were used to assess electrical conductivity. Scratch testing and abrasion resistance measurements were used to evaluate overall abrasion performance. Water contact angle and optical microscopy were used to evaluate changes in surface topography and chemistry. Graphene coated polyimide surfaces with charge dissipative resistivity (106 Ω/sq) demonstrated a minimum in residual particle areal coverage compared to conductive and insulating surfaces. Graphene ink/polymer thin film coated polyimide sheets (15 cm X 15 cm area, 75 μm thickness) are shown in order of decreasing sheet surface resistivities ranging from 103 Ω/sq, 104 Ω/sq, 106 Ω/sq, 108 Ω/sq, 1010 Ω/sq, and 1011 Ω/sq. Uncoated Kapton®, with sheet surface resistivity 1014 Ω/sq, is shown for comparison. [Display omitted] • Graphene ink coated polyimide sheets with surface resistivities in the range of 102 Ω/sq to 1012 Ω/sq have been prepared. • A significant improvement in scratch hardness (∼2 times) was observed for the coated substrates compared to the uncoated. • A minimum in residual particle areal coverage was observed for surfaces that exhibited intermediate surface resistivity values. • Dust resistant polymer films have been demonstrated for graphene coated polyimide sheets. [ABSTRACT FROM AUTHOR]

It is of significance that the wettability between the molten alloy and the Al 2 O 3 affects the inclusion removal, nozzle clogging and refractory erosion. In the present work, the wettability between the Al 2 O 3 substrate and Fe–P–Ti alloys with different Ti content was investigated by using the sessile droplets method. The interfacial characteristics were investigated by scanning electron microscope (SEM). The contact angles between the sintered Al 2 O 3 substrate and Fe–P–Ti alloys with 0, 0.05, 0.10 and 0.15 ​wt% Ti are 100.1°, 97.3°, 94.5° and 90.5°, respectively. The oxidation of [Al] and [Ti] in the molten alloys leads to the formation of the oxides on the droplets. With the increase of Ti content in the Fe–P–Ti alloys, the formed oxides change from Al 2 O 3 to Ti-containing oxides. The reaction between [Ti] and Al 2 O 3 substrate in the interface results in the formation of Ti-containing oxides. The quantity of the interfacial oxides increases with the increase of Ti content in the alloys. As a result, the synergetic effect of the formation of the interfacial products and the oxides on the surface of droplets leads to the decrease of the contact angles between the Al 2 O 3 substrate and Fe–P–Ti alloys due to the increase of Ti content. [ABSTRACT FROM AUTHOR]

Experimental studies were conducted on the evaporation rate of a droplet located on the surfaces of various composite and textured materials with different wettability at varying surface temperatures. The maximum droplet evaporation rate was recorded on a textured Cu–SiC composite material with superhydrophilic properties. The minimum droplet evaporation rate corresponded to a superhydrophobic AlMg3 substrate obtained using laser texturing with subsequent hydrophobization procedure. An increase in surface temperature led to a significant deterioration of hydrophobicity for a superhydrophobic substrate and a deterioration of hydrophilicity for a superhydrophilic substrate. As a result, with increasing temperature, the influence of the droplet geometry determined by surface wettability on the droplet evaporation rate for these substrates sharply decreases. Advancing and receding dynamic contact angles, as well as contact angle hysteresis were obtained on all studied substrates. It is generally accepted that a hydrophobic surface exhibits less contact angle hysteresis than a hydrophilic one. However, Cu-SiС composite substrate with a textured hydrophobic surface exhibited the opposite behavior. The contact angle hysteresis on the hydrophobic textured surface was found to be four times higher than that on the hydrophilic polished one. A mechanism was proposed that explains the high contact angle hysteresis and four hysteresis time modes. The minimum hysteresis value corresponded to the superhydrophobic AlMg3 substrate. Anti-corrosion properties were studied for all substrates under consideration. The minimum corrosion current corresponded to a copper substrate with a graphene coating, as well as a superhydrophobic AlMg3 substrate. For a given substrate, there are two corrosion modes with a three-fold difference in the corrosion current. In addition, the wettability behavior of different surfaces was examined using molecular dynamics simulations. The simulation results were found to be consistent with the experimental data. [ABSTRACT FROM AUTHOR]