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Rubber particles have good energy absorption and deformation ability. The incorporation of rubber particles into cement base can effectively improve the toughness of the material, and enhance the freezing resistance, cracking resistance, impact resistance and other properties of cement base. However, because rubber particles are a kind of hydrophobic substance, the interface bonding force between rubber and cement slurry is weak, and the strength of cement-based materials is decreased. Therefore, chemical and physical modification of rubber cement-based materials is studied. The results show that the modified rubber can enhance the properties of cement-based materials in two ways. First, the modifier can improve the hydrophilic of rubber by dissolving the impurities on the surface of rubber particles and forming a film on the surface. Second, the modifier reacts with the hydration product to form an effective chemical cross-link, so that the rubber particles form a close connection with the cement slurry. At the same time, it is found that rubber particles and fiber polymers have synergistic effect on the strengthening and toughening of cement-based materials. [ABSTRACT FROM AUTHOR]

In this study, the heat transfer performance of a two-phase closed thermosyphon with super-hydrophobic (SH-phobic) condenser and super-hydrophilic (SH-philic) evaporator is investigated, and the results are compared with those of a bare condenser. At 100–200 W, the total thermal resistance on the SH-phobic surface decreases by up to 10.40 %, 0.41 % and 27.44 % compared with the bare condenser surface at filling ratios of 0.25, 0.5, and 0.75, respectively. However, the total thermal resistance increases by 55.06 %, 411.35 % and 128.33 % from 300 to 400 W, respectively. The critical heat flux for the SH-phobic surface is lower than for the bare surface. The SH-phobic surface performs better than bare surface in the low-power region (100–200 W), but not in the high-power region above 300 W. Therefore, the input power should be considered when applying the SH-phobic surface to the condensing section. [ABSTRACT FROM AUTHOR]

This study developed three microstructured chitosan nanocapsules with immobilized lipase to explore chitosan-lipase interactions at different pH levels. Chitosan undergoes complete protonation or deprotonation based on pH level. Three distinct pH levels were examined: 5.5, where chitosan is fully protonated; 6.5, where chitosan is partially protonated/deprotonated; and 7.5, where chitosan is fully deprotonated. The nanocapsules exhibited nanoscale dimensions and the microstructures showed porous morphology. Immobilized lipase showed improved temperature stability, compared to free enzyme, especially in lipase supports at pH 5.5 and 7.5 due to electrostatic and hydrophobic interactions. The interactions between chitosan and lipase influenced the microenvironment around the active site, resulting in an optimum pH of 8 for all supports. Immobilized lipase at pH 5.5 and 7.5 displayed the best reusability in the hydrolysis of p-nitrophenyl palmitate under reaction conditions of 37 °C and pH 8. During refrigeration storage, all immobilized lipases maintained total activity for 7 days, but lipase immobilized at pH 6.5 maintained more the activity after 28 days. Therefore, this study has developed promising immobilized lipase, standing out not only for industrial application concerning cost-effectiveness, but also for the innovation in investigating the influence of chitosan-lipase interactions during immobilization. [ABSTRACT FROM AUTHOR]

In order to prepare cellulose aerogel oil absorbents with oil-water separation performance and flame retardancy, cellulose nanofibers were utilized as the aerogel matrix material, onto which flame-retardant montmorillonite and hydrophobic silane coatings were deposited on the fiber surface, resulting in the fabrication of flame-retardant and hydrophobic cellulose aerogels. The apparent density, flame retardancy, hydrophobicity, and oil absorption performance of the obtained aerogels were determined. It is found that the aerogels possessed fibrous structure with apparent densities ranging from 8. 10 to 9. 95 mg/cm³ and water contact angles exceeding 130°, indicating ultralight and hydrophobic characteristics. During combustion, they exhibited flameless combustion behavior and rapidly ceased burning after removal from the flame, demonstrating excellent flame retardancy. Moreover, they exhibited a maximum oil absorption capacity of (64. 63 ± 3. 29) g/g, reaching saturation oil absorption within 60 seconds, indicating excellent oil absorption performance. This aerogel provides a potential solution for oil spill treatment applications. [ABSTRACT FROM AUTHOR]

In perovskite solar cells (PSCs), the selection of the hole‐transport material (HTM) markedly influences both the achievement of high efficiency and overall stability. This study outlines the synthesis of a dopant‐free HTM founded on the donor–acceptor1–acceptor2 (D–A1–A2)‐conjugated structure and its integration into PSCs. The ensuing PSCs showcase a power conversion efficiency of 17.8%, comparable to NiOx inorganic HTM‐based devices and surpassing poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate polymeric HTM‐based devices. The efficiency comparable to NiOx is attributed to the efficient hole extraction and transport facilitated by the conjugated π junctions in the specifically designed structure. Furthermore, these devices exhibit enhanced stability, maintaining 95% of their initial performance for 60 d in an N2 atmosphere without encapsulation. The improved stability primarily arises from the hydrophobic nature of the HTM. The larger π‐conjugated molecules lead to a denser film by reducing intermolecular space, effectively retarding water intrusion and providing superior protection to the perovskite layer. Thus, the dopant‐free D–A1–A2 HTM with an extended conjugated π structure not only effectively enhances device efficiency but also substantially improves device stability. [ABSTRACT FROM AUTHOR]

Ferro hydrophobic particles possess essential properties for controlling the behavior of suspended substances in water. By adjusting the concentration of these particles, the magnetic force within the fluid carrier can be modified, leading to the emergence of distinct flow structures and patterns on the water's surface. This study examines the cloaking phenomenon exhibited by different ferroparticle conditions, employing both experimental and numerical approaches. Under the magnetic influence, hydrophilic particles can attain cloaking velocities of up to 35 mm/s, while hydrophobic particles remain unaffected by the magnetic force, remaining suspended on the water's surface. Hydrophobization of ferroparticles not only decreases their water-cloaking ability but also alters their magnetic properties. The inherent hydrophobic nature of these particles enhances water surface stability, rendering them valuable in various applications, including biomedical and self-cleaning technologies. This research holds particular significance for manipulating suspended particles in water, particularly in biomedical applications like drug delivery and tissue engineering, as well as for advancing self-cleaning technologies. [ABSTRACT FROM AUTHOR]

Supercritical fluid drying (SCFD) and ambient pressure drying (APD) are two common drying methods in the synthesis of silica aerogels (SA). The SCFD efficiently produces high-quality SA with good reproducibility, however, the produced SA is hydrophilic and has poor moisture tolerance. Meanwhile, the APD is less energy-intensive process but requires an extra amount of organic solvents and hydrophobic silanes to effectively control drying shrinkage. In this study, a new route for synthesizing hydrophobic SA is proposed, using rice husk-derived sodium silicate as a cheap precursor and without the need for high amounts of chemical reagent. First, hydrophilic SA particles (100 µm to 1.0 mm) with a large specific surface area (700 m2/g) were produced using a sol–gel method, ethanol solvent exchange, and SCFD drying. The dried hydrophilic SA were then surface hydrophobized by simple immersion in a silane reagent containing 2%, 5%, and 10% trimethylchlorosilane (TMCS) in n-hexane. These concentration of TMCS was at least ten times lower than that required by the standard APD approach, reducing chemical waste. The TMCS-modified SA shrank by 9.0–17% compared to the original SA, which slightly increasing their final density and thermal conductivity. Hydrophobization was most effective at 5% TMCS, as indicated by the largest surface area (664 m2/g), lowest thermal conductivity (0.038 W/mK), and highest water contact angle (θ = 140°). The hydrophobic SA is more thermally stable than the hydrophilic SA, which can resist temperatures as high as 350 °C. [ABSTRACT FROM AUTHOR]

The practical application of aqueous Zn‐metal anodes (AZMAs) is mainly impeded by the short cycling life and unsatisfactory reversibility springing from the notorious Zn dendrite growth and detrimental water‐induced parasitic reactions at anode‐electrolyte interface. To tackle these challenges, a multifunctional interface of Sn‐modified Ti3C2Cl2 MXene (denoted as Sn‐MXene) with high zincophilic and hydrophobic properties is rationally designed via a 1‐step strategy with a novel molten salt etching to achieve dendrite‐free Zn deposition. Experimental results and theoretical calculations reveal that the Sn nanoparticles can induce a strongly zincophilic surface with high Zn2+ adsorption, and the Ti3C2Cl2 MXene significantly decreases the surface energy of the Zn (002) plane, guiding the zinc‐preferred orientation along the (002) plane in the electroplating growth process. Moreover, the hydrophobic properties of ‐Cl terminations of the protective interface for the Zn anode can regulate Zn‐ion solvation structure to mitigate H2O‐decomposition‐induced side reactions, and guarantee a steady stream of Zn2+ flux. Encouragingly, benefiting from the Sn‐MXene layer, a side reaction‐free and dendrite‐free Zn anode with an excellent lifespan is achieved, which is further applied as an anode for full battery (Sn‐MXene‐Zn//α‐MnO2) with a long‐term span over 800 cycles under 1 A g–1 with a capacity retention of 96%. [ABSTRACT FROM AUTHOR]

This study presents the successful synthesis of a vibrant blue nanopigment derived from the metastable structure of Na‐heulandite zeolite. Employing ion exchange and coprecipitation methods with cobalt and zinc ions, followed by thermal treatment at 1100°C, resulted Co‐willemite and gahnite phases, confirmed by x‐ray diffraction and Rietveld refinement. Optical analyses verified the blue coloration, with cobalt ion transitions evident. CIE L* a* b* colorimetric analysis placed the pigment in the blue region (L* = 49.19, b* = −22, a* = −11). Application to ceramic tiles, followed by sodium dodecyl sulfate (SDS) modification, produced a nearly superhydrophobic surface (contact angle 140°, sliding angle 8°), attributed to the nano–micro structure and SDS–silica interaction. Field emission‐scanning electron microscopy images confirmed the pattern‐like surface with small patterns. These findings indicate potential self‐cleaning capabilities when exposed to dirt or water, highlighting the research's promise in enhancing ceramic functionality. [ABSTRACT FROM AUTHOR]

With the rapid development of intelligent materials in recent years, intelligent hydrophobic materials have become a new research direction, and hydrophobic surfaces with adjustable wettability have enormous application potential in many fields. Generally speaking, surface wettability is determined by the combined effect of surface chemical composition and surface morphology. Therefore, the photoresponsive wettability of azobenzene-modified surfaces can be achieved by constructing rough surface of micro-nano scale and reducing the surface free energy. In this paper, we synthesized two photo responsive hydrophobic azobenzene derivatives (AAAB-PFDT and UAAB-PFDT), characterized their structure, thermal degradation behavior, and microscopic morphology. The light conversion performance of the two materials in dispersion was also studied using a UV–Vis spectrometer. By depositing the materials on the glass slide, the measurements of the water contact angle (WCA) under different lighting conditions were performed, demonstrating that both materials exhibit excellent photoswitchable hydrophobicity and reversibility. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to offer an effective nanocomposite for potential use to consolidate and protect deteriorated archaeological pottery. Design/methodology/approach: Three nanocomposites were used in the experimental study. This study used nano Primal AC33, silicon dioxide (SiO2) and montmorillonite (MMT) nanoparticles to protect and consolidate pottery specimens. Pottery specimens were made at 800°C for this investigation. Consolidation materials were applied with a brush. The properties of the treated pottery specimens were assessed using several methods such as digital and scanning electron microscopes, static water contact angle, color alteration, physical properties and compressive strength. Findings: Microscopic examination indicated the ability of the nano Primal AC33/MMT nanocomposites to cover the outer surface well and bind the inner granules. Concerning specimens with code F treated with nano Primal AC33 5%/MMT 3% nanocomposites, it achieved an increase in contact angle (120°), density (1.23 g/cm3) and compressive strength (561 kg/cm2), as well as a decrease in color change (ΔE = 2.62), water absorption (4.45%) and porosity (5.46%). The novelty of the results is due to the characteristics of nano Primal AC33 5%/MMT 3% nanocomposites used in the current study. Originality/value: This study describes the significant results of the analytical methods used for evaluating consolidation materials used in this study. The findings offer useful information for the protection of archaeological pottery. The investigation indicated that nano Primal AC33 5%/MMT 3% nanocomposites gave the best results. Therefore, it is recommended to use this nanocomposite to consolidate archaeological pottery. As a result, the current work provides a promising first step in conserving archaeological pottery for future studies. [ABSTRACT FROM AUTHOR]

This study investigates the impact of combined texturing by micromachining and chemical functionalization on the wetting behavior and water condensation on stainless steel 304. The transition from Wenzel to Cassie-Baxter or impregnated Cassie-Baxter regimes is investigated. Understanding this transition is critical for advancing surface engineering, as it enables precise control over wetting behavior for various applications. Herein, we report on the wire EDM (wEDM) machining on stainless steel 304 to produce two distinct microstructure patterns with directional canals or pyramidal structure, and their performance in water condensation. These patterns significantly impact water condensation performance. wEDM is employed to create surface roughness, followed by phosphoric acid treatment and chemical functionalization with trichloro-1H,1H,2H,2H-perfluorooctyl silane. Contact angle measurements reveal a synergistic effect between groove direction and silane coating, leading to hydrophobic surfaces and dropwise water condensation. Specimens with directional canals exhibit a contact angle of 150°, while specimens with pyramidal structures exhibit 151o. Roll-off angle experiments showcased distinct behavior among specimens featuring canals or pyramidal structures. Specimens with canals exhibit notably lower roll-off angles compared to both flat surfaces and those with pyramidal patterns, leading to a dependence of roll-off angles on the orientation of canals. In humid environments, micromachined specimens exhibit superior water condensation capability compared to untreated SS304 surfaces. Chemically functionalized grooved specimens present larger condensate droplet diameters than flat surfaces. An enhancement in water condensation and a sevenfold higher latent heat transfer coefficient is reported. Specimens with chemical functionalization achieve corrosion protection with an efficiency reaching 82.9%. [ABSTRACT FROM AUTHOR]

The development of eco-friendly and biodegradable biopolymer composites has become increasingly important. In this study, acetylated lignin (ACL) was synthesized, and its potential as an effective additive for biodegradable polymers was investigated. ACL was synthesized through a one-step acetylation process in which hydroxyl groups of lignin were substituted with acetyl groups. ACL exhibited enhanced molecular weight and thermal stability, along with improved solubility in organic solvents compared to unmodified kraft lignin (KL). Hydrophobic ACL was uniformly dispersed in a mixture of a polycaprolactone (PCL) polymer and organic solvent, leading to the successful fabrication of a fibrous mat using electrospinning. The ACL/PCL fibrous mat demonstrated enhanced mechanical strength and hydrophobicity, notably indicating a substantially high-water contact angle of 143.3 ± 1.4°. Subsequently, it was utilized as a water/oil separator, showing a separation efficiency exceeding 90% for oil within a short time, effectively addressing water/oil emulsions. Biodegradability results demonstrated enhanced hydrolysis degradation efficiency with the incorporation of ACL into PCL fibers. Consequently, this study proposes a feasible approach to enhance the efficacy of ACL as a biodegradable polymer additive, while presenting promising opportunities for membrane applications targeting water/oil separation. [ABSTRACT FROM AUTHOR]

The direct nanoimprinting of silver nanoparticles (Ag NPs) generated a plasmonic metallic nanostructure. The Ag NPs used in this study have been synthesized by a phase transfer method. The procedure comprised the utilisation of sodium borohydride to reduce silver nitrate in the presence of a stabilizing agent, which facilitated the transfer of the NPs from the aqueous phase to an organic phase, resulting in uniform and stable particles. The size and shape of the Ag NPs were characterized using electron microscopy, revealing spherical particles with an average diameter of 9 nm. The XRD examination revealed that the nanoparticles exhibit a high degree of crystallinity and possess a cubic geometric phase. The UV-visible absorption spectra demonstrate a significant level of homogeneity in the size. The silicon surface imprinted with Ag NPs exhibits hydrophobic behaviour towards water molecules. This approach allows for precise control of Ag NPs on the substrate, resulting in a robust and effective platform for future applications in sensor technology. Furthermore, the hydrophobic nature of the imprinted surface suggests potential applications in water-repellent coatings or self-cleaning materials. [ABSTRACT FROM AUTHOR]

Study of sodium silicate from rice husks as coating material is reported. The extraction was conducted via precipitation method with sodium hydroxide, nitric acid and ethanol at pH 8. The resulting silica was tested as hydrophobic coating by coating it on a glass surface. Based on the value of the contact angle, silica has good hydrophobic properties. The highest hydrophobic properties were obtained from sample, which labeled as Si10A:Si5B with an average contact angle of 105.3 °. Investigation of the potential application of sodium silicate as an inhibitor of corrosion has been conducted by coating it on steel surfaces. The effect of the concentration of sodium silicate was conducted at 0, 10, 20 and 30 ppm and found that the morphology of steel coated with 20 ppm has the lowest corrosion rate with 81 % inhibition efficiency. [ABSTRACT FROM AUTHOR]

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Multifunctional anti-corrosive coatings are a key focus in the development of modern coatings. In this study, the corrosion inhibitor benzotriazole (BTA) was loaded onto fumed silica (SiP) through physical adsorption, and then the surface of SiP was modified with octadecyl trimethylsilane (OTMS) to create a modified fumed silica supported by BTA (BTA-SiP@OTMS). The resulting sample was blended with epoxy resin to create a composite coating with both anti-corrosive and hydrophobic properties. The OTMS modification effectively covers the surface of the fumed silica, transforming the composite coating from hydrophilic to hydrophobic. This hydrophobicity prevents the penetration of corrosive mediums. The addition of BTA-SiP@OTMS significantly increases the impedance value of the composite coating, indicating improved corrosion resistance. Due to its hydrophobic and anti-corrosion properties, the composite coating shows promising potential in weather-resistant coatings. [ABSTRACT FROM AUTHOR]

Transparent hydrophobic glass materials had played an important role in our daily life, but some problems such as complex or expensive manufacturing processes, poor wear resistance and opacity limited its applications. In this paper, a composite silica sol composed of modified SiO2 nanoparticles and transparent special water-based silicone resin was prepared. An organic-inorganic hybrid coating was formed on the glass surface by a simple spraying method to produce a hydrophobic surface with high transparency and durability. Perfluorinated polyether (PFPE) chains with lower surface energy were introduced into the silica sol prepared above. The composite coatings had both the low surface energy of fluorine-containing substances and the rough structure. The surface topography, static water contact angle, self-cleaning performance, anti-fouling performance, wear resistance, adhesion performance, acid and alkali resistances of the coating were tested. The results showed that the maximum water contact angle of the prepared transparent hydrophobic glass can reach 140°. The coating had good adhesion performance, wear resistance, self-cleaning and acid resistant, but poor alkaline resistance. Highlights: Wear-resistant self-cleaning silicon sol coating was developed. Perfluorinated polyether (PFPE) chains improved the hydrophobicity of the surfaces. The effect of KH550 and KH560 with different volume ratios on the coating properties was investigated. Hydrophobic coating was developed on glass substrates by spray-coating. [ABSTRACT FROM AUTHOR]

This study presents a successful synthesis of natural magnetic silica (NMM@SiO2) materials modified with hydrophobic groups for the adsorption of two antibiotics, chloramphenicol (CAP) and ciprofloxacin (CIP). The NMM@SiO2 was prepared using natural magnetic material (NMM) isolated from iron sand, silica extracted from quart sand, and methyltrimethoxysilane (MTMS) as the hydrophobic precursor. The synthesized materials were characterized using various analytical techniques, including FTIR, XRD, VSM, TGA, TEM, and SEM-EDX-Mapping. Subsequently, the synthesized materials were used to adsorb antibiotics from an aqueous solution using a batch system, and the antibiotic concentration in the solution was measured with UV-VIS spectrophotometry. The characterization results confirmed the successful incorporation of MTMS onto NMM@SiO2. The adsorption studies indicated that the optimum pH for CAP and CIP adsorption were 5 and 6, respectively, with the optimum contact time being 120 min for CAP and 90 min for CIP, and the initial antibiotic concentrations of 200 mg L−1. The NMM@SiO2 (1.5 g) modified with 0.4 g (3.0 mmol) of MTMS to obtain NMM@SiO2/C1(3) exhibit the highest adsorption capacities for both antibiotics (58.46 mg g−1 for CAP and 106.81 mg g−1 for CIP). For both antibiotics tested, the kinetics and the adsorption isotherms followed pseudo-second-order and Freundlich models, respectively. The thermodynamic study indicated a negative ΔH (exothermic), positive ΔS (increase in randomness), and negative ΔG (spontaneous) for CAP and CIP. These results highlight the successful performance of this hydrophobic-based natural material adsorbent and demonstrate its potential as an effective adsorbent for antibiotic adsorption in aquatic environments.

Nowadays, researchers are interested in surface modification of bearings by adding texture to increase bearing performance. Regrettably, modifications in surface roughness can induce cavitation. Conversely, slip engineering can enhance pressure to effectively eliminate cavitation. The objective of this work is to present a 3D design for thrust bearing that integrates pockets and slip engineering techniques in order to improve the load carrying capacity of the bearing and reduce cavitation. The originality of this study on thrust bearing is in the integration of surface texture, slip engineering, and cavitation. A CFD modeling approach is employed to simulate the slip formation in the design. Implementing slip induces hydrophobicity on the surface by introducing velocity to the fluid at the contact with the bearing pad. The simulation involves two types of bearings: radial pocket and multitexture, each with various slip positions. The important study's findings indicate that the radial pocket design, which incorporates slip formations both between and inside the pocket, can enhance the load carrying capacity by as much as 259.2 % compared to the absence of slip formation. When using the multitexture type, the load bearing capability can rise by up to 179 %. In the multitexture configuration, pressure is uniformly distributed throughout the bearing surface. To enhance the comprehensiveness of the research, the findings of this study are also compared to those of earlier conducted studies on circumferential pocket and closed pocket types. Arranging slip correctly has been empirically shown to enhance the load carrying capability of bearings.

PM2.5 filters with hydrophobicity and thermal resistance are preferable for automobile cabins, engine air intake, and indoor applications, safeguarding against moisture ingress, microbial growth, and temperature fluctuations, and ensuring optimal air quality. This study explored the effects of blending five fibres with different web arrangements and fibre blend compositions on needle-punched dust-holding, hydrophobic, and thermal properties. Polyphenylene sulfide (PPS), polypropylene (PP), polyester (PET), polylactic acid (PLA), and polyacrylonitrile (PAN) were blended in different proportions to produce the samples. The method included opening, blending, carding, web laying, and needle punching to produce eight samples with cross-laid, parallel-laid, and pre-needled parallel-laid web configurations. Standard test methods were employed for the characterization. The results showed a dust holding capacity of > 3,423,000 particles/cm2, the highest WCA of 133.12°, and the highest thermal resistance of 0.24255 m2KW−1. Based on the ANOVA analysis, web arrangement and pre-needling did not have a significant impact on the hydrophobicity of the samples. N0, N1, and N2 showed similar high water contact angles (~ 126°), indicating that the hydrophobicity was more affected by the chemistry of the fibre blend than by the web structure. Turkey’s analysis of other samples strengthened this idea. However, they had a substantial impact on the porosity, air permeability, dust-holding capacity, and thermal properties at a P-value ≤ 0.05. The findings provide insightful information regarding the complex interactions among fibre content, web layout, and pre-needling to develop sophisticated needle-punched PM2.5 filters.

Abstract The stability of soil organic matter (SOM) that governs soil organic carbon (SOC) storage depends on its characteristics and components, but little is known about how tree species in forest ecosystems affect SOM components and characteristics. In this study, we used FTIR spectroscopy to investigate plantations of two ecologically and economically significant tree species—namely, spruce (Picea spp.) and sycamore (Acer pseudoplatanus)—in order to determine how the different litter inputs and root-microbe interactions of these two plantations affect the functional groups, components, and characteristics of their SOM. Soil samples were taken from the topsoil (0–10 cm) and subsoil (10–20 cm). In the 0–10 cm soil depth, the SOM's hydrophilic, hydrophobic, and aromatic components differ between the spruce and sycamore plantations. The hydrophobic components constitute the primary constituents of the SOM of the two forest plantations, in contrast to the expected predominance of the hydrophilic component of the SOM. Also, the high hydrophobicity (hydrophilic/hydrophobic) in the subsoil of the spruce plantations was attributed to a decrease in hydrophilic components and a subsequent increase in hydrophobic components of the SOM. The sycamore plantations exhibited a higher SOM aromaticity and a greater degree of decomposition than the spruce plantations. The aforementioned distinctions emphasise the contrasting mechanisms involved in transforming and turnover of the two-tree species' soil organic matter (SOM).

Abstract Bio-based coating materials have received increased attention because of their low-cost, environmentally friendly, and sustainable properties. In this paper, a novel coating material was developed to coat ureas using bio-based coating material derived from liquefied eggplant branches to form controlled-release ureas (CRUs). Also, the optimum proportion of liquefier was studied. Furthermore, dimethyl siloxane was used to modify liquified eggplant branches to make them hydrophobic, resulting in hydrophobic controlled-release ureas (SCRUs). This hydrophobic-enabled coating is environmentally friendly and highly efficient. The products were characterized by specific scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry, and the water contact angles of CRUs and SCRUs were determined. The nutrient-release characteristics of the SCRUs in water were determined at 25 °C and compared with those of CRUs. The results showed that the modification with dimethyl siloxane reduced the N release rate and increased the longevity of the fertilizer coated with hydrophobic bio-based coating material. In addition, organosilicon atoms on the SCRU surface also block the micro-holes on the coating and thus reduce the entry of water onto the coating. The results suggest that the new coating technology can create a hydrophobic surface on bio-based coating material and thus improve their controlled-release characteristics.

Abstract Electrowetting behaviour for carbon nanotubes (CNT) grown on stainless steel mesh was investigated. The effect of temperature, time, and applied bias voltage on the contact angle of water droplets was studied. The impact of temperature variation on contact angle was also performed for the temperature ranging from 25 to 70 °C. A decrement of contact angle by 68% was observed for the mentioned range indicating a transition from a hydrophobic to hydrophilic nature. A similar trend was observed on the application of electric potential to the CNT-modified stainless-steel mesh ranging from 0 to 8 V with a transition of contact angle from 146 to 30 deg respectively. A comparative analysis for the contact angle variation with time for CNT-coated mesh and uncoated mesh was performed for 180 min. It is observed that uncoated mesh shows a reduction in contact angle to 0 deg with time while the CNT coated mesh shows surplus hydrophobicity with a 2 deg decrement in the extent of time. CNT-modified mesh successfully absorbs 95% of rhodamine B (RB) dye and detergent from water in 10 cycles.

This research aims to develop hydrophobic and antibacterial properties of textiles using chitosan and silica oxide (SiO2) nanocomposite coating. SiO2 was extracted from rice husk ash and chitosan from crustacean shells. SiO2 and chitosan powder were pulverized using High Energy Milling (HEM). The nanocomposite was synthesized using the sol-gel method with concentration variations of 0.2 %:0.4 %, 0.4 %:0.6 %, 0.6 %:0.8 %, and 0.8 %:1 %. Textile coating was carried out by dip coating method with variations of 1x, 2x, 3x, and 4x dyeing. The crystal structure and size of the nanocomposites were obtained using X-ray Diffraction (XRD). Surface morphology and particle size were obtained using a Scanning Electron Microscope (SEM). The contact angle was measured using the sessile drop method. The bacterial activity tests were conducted by measuring the surface temperature of textiles with a thermal camera after being irradiated with UV-C. The ability of textiles to inhibit bacterial growth was tested using Staphylococcus aureus bacteria. The results showed that the smallest crystal size obtained was 30.21 nm. The amount of particle size and contact angle are significantly influenced by the quality of Citosan-SiO2 and coloring changes. The smallest particle size obtained is 32 nm. The highest value of contact angle obtained was 161° The average surface temperature of the textile after being irradiated with UV-C reached 40.7 °C. The highest zone of inhibition obtained was 17 mm and is in the strong category. This research shows that textiles coated with chitosan-SiO2 can inhibit bacterial growth and have potential applications in the clothing industry.

Background Graphene is the thinnest, strongest, and stiffest imaginable material. The biocompatible property of graphene oxide can initiate and facilitate cell adhesion, proliferation, and differentiation of periodontal ligament, osteogenic, and oral epithelial cells. Furthermore, the antibiofilm and anti-adhesion properties of graphene oxide in the prevention of dental biofilm infections, dental caries, and dental erosion as well as for implant surface modification and as an anti-quorum sensing agent. Composites are the most often utilized materials for restoration in the field of dentistry due to adhesive resins' improved mechanical and cosmetic properties. To safeguard the dentin and prevent dental cavities, dentin adhesives are utilized to affix hydrophobic resin composites to hydrophilic dentin tissue. Materials and Method Dental adhesives have a harder time adhering to dentin because it contains more water and is less mineralized than enamel. This makes the method more sensitive. Result As a result, it was chosen to assess and contrast the impact of 5% Hydroxyapatite nanoparticles and 2% Graphene oxide nanoparticles, both separately and together, on the Micro tensile bond strength of 5th generation adhesive. Conclusion Graphene oxide is the most versatile form of Graphite in structural and functional configuration. Graphene oxide possesses extraordinary physical, chemical, optical, electrical and mechanical properties. Among the graphene family nanomaterials, the reduced form of Graphite adding the oxygenated functional group to the structure increases the surface area and therefore exhibits enviable excellent interaction ability with metal and ions as well as organic species. Graphene oxide in dentistry has provided outstanding results in antimicrobial action, regenerative dentistry, bone tissue engineering, drug delivery, physicochemical properties, enhancement of dental biomaterials and oral cancer treatment.

One-pot syntheses and in situ ultrasonication have been optimized to generate tunable and highly hydrophobic 2,7-octadienyl-ether (ODE) cellulose nanofibrils (CNFs). Using only butadiene sulfone to serve as dual reaction medium and precursor to 1,3-butadiene (1,3-BD) for telomerization with cellulose hydroxyls, the OH-to-ODE conversion significantly improved from ca. 0.7 to 1.2, 1.8, 3.1, and 4.1 mmol of ODE/g-cellulose at 103-110 °C for 1-2 h. Ultrasonication was highly effective and versatile in the direct disintegration of ODE-cellulose (ODE-cell) in nonpolar organic solvents and plant oils into ODE-CNFs as well as pretreating cellulose for improved functionalization. Mixing 2 wt % in situ ultrasonicated 1.2 mmol of ODE/g-cell improved the modulus of polybutadiene six times and the strength of poly(styrene-b-isoprene-b-styrene) three times, whereas in situ ultrasonication of 1.8 mmol/g-cell directly with linseed oil at merely 0.07 wt % created holistic biobased hydrophobic cellulose paper to resist water penetration while also significantly improving the tensile strength. This optimized telomerization and streamlined in situ ultrasonication approach has presented a sustainable synthesis and processing strategy to generate highly hydrocarbon-compatible nanocelluloses previously unattainable.

Wetting functionalities of rough surfaces are largely determined by the Laplace pressure generated across liquid–gas interfaces formed within surface structures. Typically, rough wetting surfaces create negative Laplace pressures, enabling capillary wicking, while rough non-wetting surfaces create positive Laplace pressures, exhibiting fluid repellency. Here, with microfabricated reentrant structures, it is shown that the same surface can exhibit either a negative or positive Laplace pressure, regardless of its intrinsic wettability. This material-independent Laplace pressure duality enables or enhances a range of wetting functionalities including wicking, switchability, and selectivity. On the same surface, capillary rise, capillary dip, and the combination of the two which leads to further enhancement of the total sustainable capillary height and Laplace pressure, the driving force for wicking is demonstrated. Further, active switching of wetting states between the hemiwicking and the repellent Cassie state on reentrant structures is shown. Moreover, with a water-hexane mixture system, selective wetting of reentrant structures are demonstrated, that is, water can be selectively wicked or repelled in the presence of hexane, and vice versa. These functionalities are achieved, which would typically require complex chemical coatings, solely using surface structures, thus largely expanding the design space for a wide range of thermofluidic applications.

The anti/de-icing methods are mainly divided into two types: active method and passive method. The passive method generally adopts three ideas: reducing water contact, inhibiting water icing and reducing ice adhesion. Silica aerogels, which have adjustable surface wettability, thermal conductivity and porosity, would be designed to satisfy the requirement for passive anti/de-icing methods. In this work, the organic–inorganic hybrid aerogels based on organosilicon were facilely prepared in a sol–gel procedure, which showed hydrophobic and elastic properties. It could be seen that the thermal insulation effect originating from aerogel-like porous network endowed the efficient anti-icing property. Moreover, the lowest ice adhesion strengths of the above silica aerogels and the related oil-based lubricant-filled aerogels were 7.1kPa and 5kPa, respectively, which belonged to the icephobic surface. Besides, the ice adhesion strength only increased to 15.6kPa after 30 icing–deicing cycles, showing that hydrophobic and elastic silica aerogels had efficient deicing durability. [ABSTRACT FROM AUTHOR]

Breathable membranes with micropores enable the transfer of gas molecules while blocking liquids and solids, and have a wide range of applications in medical, industrial, environmental, and energy fields. Breathability is highly influenced by the nature of a material, pore size, and pore structure. Preparation methods and the incorporation of functional materials are responsible for the variety of physical properties and applications of breathable membranes. In this review, the preparation methods of breathable membranes, including blown film extrusion, cast film extrusion, phase separation, and electrospinning, are discussed. According to the antibacterial, hydrophobic, thermal insulation, conductive, and adsorption properties, the application of breathable membranes in the fields of electronics, medicine, textiles, packaging, energy, and the environment are summarized. Perspectives on the development trends and challenges of breathable membranes are discussed. [ABSTRACT FROM AUTHOR]

Aluminum alloy 2024 is the most widely used metal alloy in aircraft due to its superior characteristics. Although the effects of surface chemistry and topography on the wettability transition have been investigated in the literature, it has not yet been clarified which mechanism is more dominant. In this study, the super-hydrophobic Al2024 sample surfaces were obtained over time in a single step using a nanosecond pulsed fiber laser. Different micro- and nano-structures were produced by changing the laser output power and scanning speed. The effects of laser parameters on the wettability of the Al2024 samples were examined. As with the untreated sample, all fresh laser-treated samples have a hydrophilic or super-hydrophilic surface property. It was found that the fresh laser-treated aluminum alloy surfaces were super-hydrophilic. Then, the Al2024 samples were exposed to ambient air for a certain period. It was found that the contact angles (CAs) of all laser-treated Al2024 samples increased over time. Also, the water drop moved away from the surface of some super-hydrophobic samples at angles of less than 10°. With more than 150° water contact angle and less than 10° sliding angle, it was proved that the lotus effect was obtained at various time scales. The icing properties of the lotus sample were investigated. The surface icing characteristics of the lotus sample have been improved. The XPS high resolution analyses show that the Al-C bond could be responsible for the wettability transition of the laser-ablated samples from hydrophilic to super-hydrophobicity (lotus). [ABSTRACT FROM AUTHOR]