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1.
J Funct Biomater ; 15(8)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39194646

RESUMO

Dental restorations must replicate the natural appearance of teeth while ensuring biocompatibility and durability. This study evaluated the surface characteristics and color stability of three dental composites-Herculite Ultra XRV, G-ænial A'CHORD, and Omnichroma-exposed to acidic beverages (red wine, black coffee, and Coca-Cola). Sixty disk-shaped specimens were prepared, polished, and immersed in these beverages. Surface roughness was assessed using profilometry and SEM analysis, hydrophobicity via contact angle analysis, and surface charge through streaming potential measurements. Color stability was evaluated using a spectrophotometer, and the pH levels of the solutions were recorded. Results showed that Herculite Ultra XRV had the highest mean contact angle (79.46° ± 6.52), indicating superior hydrophobicity, while Omnichroma had the lowest (64.94° ± 3.08), indicating more hydrophilicity. Significant color changes were observed, especially in black coffee, with ∆E values indicating notable discoloration. The acidic pH of the solutions increased surface roughness and color changes. Statistical analyses confirmed significant increases in surface roughness and color change for all composites, with the nanohybrid resin composite showing the greatest variability. These findings highlight the need for dental restorative materials with enhanced resistance to acidic environments to improve the longevity and esthetics of dental treatments.

2.
J Sci Food Agric ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030951

RESUMO

BACKGROUND: The first step in the contamination of leafy vegetables by human pathogens is their attachment to the leaf surface. The success of this is influenced strongly by the physical and chemical characteristics of the surface itself (number and size of stomata, presence of trichomes and veins, epicuticular waxes, hydrophobicity, etc.). This study evaluated the attachment of Salmonella enterica to 30 baby-leaf salads and tested whether the differences found among them were related to the following leaf traits: hydrophobicity, roughness, and epicuticular waxes. RESULTS: Differences in susceptibility to contamination by S. enterica were found between the 30 baby-leaf salads investigated. The lowest attachment was found in wild lettuce (Lactuca serriola L.) and lamb's lettuce 'Trophy F1' (Valerianella locusta [L.] Laterr.), with values of 1.63 ± 0.39 Log(CFU/cm2) and 1.79 ± 0.54 Log(CFU/cm2), respectively. Attachment was correlated with hydrophobicity (measured as contact angle) (r = -0.39) and epicuticular waxes (r = -0.81) but not with roughness (r = 0.24). The most important wax components for attachment were alcohols and, in particular, the three-dimensional (3D) wax crystals of C26 alcohol, but fatty acids probably also had a role. Both these compounds increased hydrophobicity. The presence of thymol, whose antimicrobial properties are well known, was found in lamb's lettuce. CONCLUSIONS: The findings of this study can help to predict and control the attachment and contamination of leafy salads by enterobacteria. They also provide useful information for breeding programs aiming to develop cultivars that are less susceptible to human pathogens, enhancing the food safety of vegetables. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

3.
Sci Total Environ ; 948: 174731, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-39002587

RESUMO

Canopy interception significantly affects hydrological processes such as infiltration, runoff and evapotranspiration. Research on grass canopy interception remains limited, and the experimental methods employed differ substantially. To thoroughly investigate the canopy interception characteristics of grass and clarify the methodological differences, five commonly utilized slope protection grass species in temperate regions were cultivated in a laboratory setting, and their canopy interception characteristics were experimentally investigated using the water-balance method (WBM), the water-wiping method (WWM) and the water-immersion method (WIM), respectively. The results showed that the WBM is more accurate for measuring canopy interception in grass, whereas both the WWM and the WIM underestimate grass canopy interception capacity. The canopy interception capacity measured by the WBM was 1.61-2.09 times higher than that of the WWM and 1.93-3.47 times higher than that of the WIM. Grey correlation analysis of the eight evaluated factors indicated that leaf area is the most influential factor affecting canopy interception in grass, followed by rainfall amount, dry mass, rainfall intensity, canopy projection area, leaf contact angle, fresh weight, and average height. There is a negative power function relationship between the interception ratio and the rainfall amount. With increasing rainfall intensity, the canopy interception capacity initially increases and then decreases, peaking at rainfall intensities of 15 to 20 mm/h. Leaf contact angle is a key quantifiable parameter that explains the differences in canopy interception among different grass species, and the canopy interception per unit leaf area decreases as the leaf contact angle increases. This study demonstrates that the WBM provides the most accurate measurements of grass canopy interception compared to the WWM and WIM, and highlights the leaf contact angle as a key factor in explaining interspecies differences. These findings could enhance the understanding of grass canopy interception and guide the selection of experimental methods.


Assuntos
Poaceae , Poaceae/fisiologia , Folhas de Planta/fisiologia , Conservação dos Recursos Naturais/métodos , Chuva , Hidrologia , Monitoramento Ambiental/métodos
4.
J Esthet Restor Dent ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963682

RESUMO

OBJECTIVE: To evaluate the effect of the deterioration of computer aided design/computer aided manufacturing (CAD/CAM) burs during zirconia milling, on surface roughness, contact angle, and fibroblast viability. MATERIALS AND METHODS: Ceramic blocks were milled and 75 ceramic disks (8 × 1.5 mm) made and allocated into three groups (n = 25): G1-brand new 2L and 1L burs, G2-2L bur at the end of lifetime and brand new 1L bur and G3-both burs at the end of their lifetimes. Roughness (Ra, Rq, and Rz) was evaluated using a 3D optical profilometer, the contact angle by the sessile drop method and the cell viability of the mouse NIH/3T3 fibroblast, using the Alamar Blue assay at intervals of 24, 48, and 72 h (ISO 10993-5). Data were analyzed by one-way ANOVA and Kruskal-Wallis tests (p ≤ 0.05). RESULTS: Roughness increased as the burs deteriorated and G3 (0.27 ± 0.04) presented a higher value for Ra (p < 0.001). The highest contact angle was observed in G3 (86.2 ± 2.66) when compared with G1 (63.7 ± 12.49) and G2 (75.3 ± 6.36) (p < 0.001). Alamar Blue indicated an increase in cell proliferation, with no significant differences among the groups at 24 and 72 h (p > 0.05). CONCLUSIONS: The deterioration of the burs increased the surface roughness and decreased the wettability, but did not interfere in cell viability and proliferation. CLINICAL SIGNIFICANCE: The use of custom zirconia abutments represents an effective strategy for single crowns restorations. Our findings suggest that these abutments can be efficiently milled using CAD/CAM burs within their recommended lifetime.

5.
Materials (Basel) ; 17(13)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38998139

RESUMO

In this paper, glow nitriding processes at cathode potential are used at various temperatures to investigate how they affect the corrosion resistance of 316L steel in ethanol at temperatures of 22 °C and -30 °C. Lowering the test temperature reduces the corrosion rate of the nitrided layers. Conversely, glow nitriding at 450 °C improves the corrosion resistance of the tested steel. Increasing the nitriding temperature to 520 °C increases the corrosion rate. It should be noted that the ethyl alcohol solution, due to the lack of aggressive ions, does not cause significant changes in the corrosion rate of the steel. The value of the corrosion current varies in the range of 10-2-10-3 µA/cm2. Nitrided layers increase the contact angle measured for water and are entirely wettable for ethanol. The objective of this study is to evaluate the effect of the nitriding temperature of AISI 316L steel on its corrosion resistance in an ethanol solution at room temperature and at -30 °C.

6.
J Biomater Sci Polym Ed ; : 1-15, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949409

RESUMO

The interest in wound dressings increased ten years ago. Wound care practitioners can now use interactive/bioactive dressings and tissue-engineered skin substitutes. Several bandages can heal burns, but none can treat all chronic wounds. This study formulates a composite material from 70% polyvinyl alcohol (PVA) and 30% polyethylene glycol (PEG) with 0.2, 0.4, and 0.6 wt% magnesium oxide nanoparticles. This study aims to create a biodegradable wound dressing. A Fourier Transform Infrared (FTIR) study shows that PVA, PEG, and MgO create hydrogen bonding interactions. Hydrophilic characteristics are shown by the polymeric blend's 56.289° contact angle. MgO also lowers the contact angle, making the film more hydrophilic. Hydrophilicity improves film biocompatibility, live cell adhesion, wound healing, and wound dressing degradability. Differential Scanning Calorimeter (DSC) findings suggest the PVA/PEG combination melted at 53.16 °C. However, adding different weight fractions of MgO nanoparticles increased the nanocomposite's melting temperature (Tm). These nanoparticles improve the film's thermal stability, increasing Tm. In addition, MgO nanoparticles in the polymer blend increased tensile strength and elastic modulus. This is due to the blend's strong adherence to the reinforcing phase and MgO nanoparticles' ceramic material which has a great mechanical strength. The combination of 70% PVA + 30% PEG exhibited good antibacterial spatially at 0.2% MgO, according to antibacterial test results.

7.
Dent Mater J ; 43(4): 582-590, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38960667

RESUMO

The purpose of this study was to evaluate the effect of the atmospheric pressure plasma treatment as a surface treatment method on the contact angle and shear bond strength (SBS) of zirconia ceramics and the failure mode between the self-adhesive resin luting agent and zirconia. The zirconia specimens were divided into eight groups based on the surface treatment method: alumina blasting, air plasma, argon plasma (AP), Katana cleaner, ozonated water, ozonated water+AP, Katana cleaner+AP, and tap water+AP. The contact angles, SBS, and fracture modes were tested. AP treatment significantly reduced the contact angle (p<0.0001). The combination of AP and other cleaning methods showed a higher bond strength and more mixed fractures. Our findings indicate that using atmospheric pressure plasma with argon gas, combined with other cleaning methods, results in a stronger bond than when using alumina blasting alone.


Assuntos
Argônio , Colagem Dentária , Teste de Materiais , Gases em Plasma , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície , Zircônio , Zircônio/química , Gases em Plasma/química , Colagem Dentária/métodos , Cimentos de Resina/química , Argônio/química , Análise do Estresse Dentário , Óxido de Alumínio/química
8.
Heliyon ; 10(12): e32493, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38975209

RESUMO

This in vitro study was to evaluate the effect of different non-thermal atmospheric pressure plasma (NTP) on shear bond strength (SBS) between yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) and self-adhesive resin cement. In this study, The Y-TZP specimens were divided into 4 groups according to the surface treatment methods as follows: Control (no surface treatment), Sb (Sandblasting), AP(argon NTP), and CP(20 % oxygen and 80 % argon combination NTP). Y-TZP specimens were randomly selected from each group to observe and test the following indexes: scanning electron microscope to observe the surface morphology; atomic force microscope to detect the surface roughness; contact angle detector to detect the surface contact angle; energy spectrometer to analyze the surface elements. Then, resin cement (Rely X-U200) was bonded to human isolated teeth with Y-TZP specimens to measure SBS. The results showed that for the SE test, the NTP group was significantly higher than the control group (p < 0.05). The results of the SBS test showed that the SBS values of the NTP group were significantly higher than those of the other groups, regardless of the plasma treatment (p < 0.05). However, there was no significant difference between groups AP and CP in a test of SBS (p > 0.05). This study shows that non-thermal atmospheric pressure plasma can improve the shear bond strength of Y-TZP by increasing the surface energy. The addition of oxygen ratio to argon is more favorable to increase the shear bond strength and is worth further investigation.

9.
Zoology (Jena) ; 165: 126181, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38833995

RESUMO

Climbing animals such as geckos and arthropods developed astonishing adhesive mechanisms which are fundamental for their survival and represent valuable models for biomimetic purposes. A firm adhesion to the host surface, in order to successfully lay eggs is necessary for the reproduction of most parasitoid insects. In the present study, we performed a comparative investigation on the attachment ability of four parasitoid species (the egg parasitoid Anastatus bifasciatus (Eupelmidae), the aphid parasitoid Aphidius ervi (Braconidae), the fly pupal ectoparasitoid Muscidifurax raptorellus (Pteromalidae) and the pupal parasitoid of Drosophila Trichopria drosophilae (Diapriidae)) with hosts characterized by a surface having different wettability properties. The friction force measurements were performed on smooth artificial (glass) surfaces showing different contact angles of water. We found that attachment systems of parasitoid insects are tuned to match the wettability of the host surface. Sexual dimorphism in the attachment ability of some tested species has been also observed. The obtained results are probably related to different microstructure and chemical composition of the host surfaces and to different chemical composition of the parasitoid adhesive fluid. The data here presented can be interpreted as an adaptation, especially in the female, to the physicochemical properties of the host surface and contribute to shed light on the coevolutionary processes of parasitoid insects and their hosts.

10.
Food Chem ; 458: 140183, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38943954

RESUMO

This study aimed to investigate the fundamental properties, solubility, mechanical properties, barrier performance, and microstructural features of films composed of corn starch and glycerol. Changes in the microstructure were analyzed to understand how they relate to the physical and chemical properties of these films. Specifically, we found that increasing the gelatinization time decreased the film thickness, solubility, water vapor permeability, and maximum degradation temperature and increased the water content. A gradual increase in the water contact angle of the corn starch-glycerol films was observed with increasing gelatinization time. This trend is likely due to the disruptive effect of gelatinization on the crystalline and amorphous structures inherent in corn starch, resulting in reduced film crystallinity, degree of order (DO) and degree of double helix (DD).


Assuntos
Glicerol , Solubilidade , Amido , Zea mays , Amido/química , Glicerol/química , Zea mays/química , Permeabilidade , Embalagem de Alimentos/instrumentação , Água/química , Gelatina/química
11.
Molecules ; 29(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38930943

RESUMO

The complex and variable structure of subsurface oil reservoirs as well as the small pore throat size of reservoirs make it extremely important to investigate the effect of oil-water-rock interactions for enhancing oil recovery. In this paper, the powder wettability of oil sand with different polar solvents was investigated using the improved Washburn capillary rise method, and the surface free energy of oil sand was calculated in combination with the OWRK method. In addition, the wettability of anionic surfactants HABS and PS solutions on the surface of oil sand was determined, and it showed that their wetting rates showed different trends after CMC (critical micelle concentration). The C×cosθ value of HABS decreased significantly with increasing concentration, whereas PS showed little changes. This may be related to the aggregate structure formed by HABS on the oil sand surface. Meanwhile, the interfacial free energy between crude oil and oil sand was obtained by crude oil-to-oil sand wetting experiments, and found that the wetting rate of crude oil to oil sand was much lower than that of solvents and surfactants. In combination with the above results and the oil-water interfacial tension (IFT), the oil-water-rock three-phase contact angle and the work of adhesion between the crude oil and the solid were obtained by Young's equation. From the three-phase contact angle results, it can be found that the contact angle values of both HABS and PS are obviously higher than that of the simulated water, and both HABS and PS have the ability to significantly reduce the work of adhesion, which shows a strong ability to strip the oil film on the surface of the solid. The research results of this paper are helpful to understand the oil displacement mechanism of chemical flooding in reservoir pores, which is of great significance for improving oil recovery.

12.
Sci Rep ; 14(1): 13781, 2024 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877138

RESUMO

This study explores the modification of silk fibroin films for hydrophilic coating applications using various sugar alcohols. Films, prepared via solvent casting, incorporated glycerol, sorbitol, and maltitol, revealing distinctive transparency and UV absorption characteristics based on sugar alcohol chemical structures. X-ray diffraction confirmed a silk I to silk II transition influenced by sugar alcohols. Glycerol proved most effective in enhancing the ß-sheet structure. The study also elucidated a conformational shift towards a ß-sheet structure induced by sugar alcohols. Silk fibroin-sugar alcohol blind docking and sugar alcohol-sugar alcohol blind docking investigations were conducted utilizing the HDOCK Server. The computer simulation unveiled the significance of size and hydrogen bonding characteristics inherent in sugar alcohols, emphasizing their pivotal role in influencing interactions within silk fibroin matrices. Hydrophilicity of ozonized silicone surfaces improved through successful coating with silk fibroin films, particularly glycerol-containing ones, resulting in reduced contact angles. Strong adhesion between silk fibroin films and ozonized silicone surfaces was evident, indicating robust hydrogen bonding interactions. This comprehensive research provides crucial insights into sugar alcohols' potential to modify silk fibroin film crystalline structures, offering valuable guidance for optimizing their design and functionality, especially in silicone coating applications.


Assuntos
Fibroínas , Interações Hidrofóbicas e Hidrofílicas , Álcoois Açúcares , Fibroínas/química , Álcoois Açúcares/química , Ligação de Hidrogênio , Materiais Revestidos Biocompatíveis/química , Difração de Raios X , Simulação de Acoplamento Molecular
13.
BMC Oral Health ; 24(1): 681, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867263

RESUMO

BACKGROUND: Surface tension and contact angle properties, which play a crucial role in determining the effectiveness of irrigation solutions in penetrating dentin surfaces and dentin tubules, are highly important for the development of new irrigation solutions and their preferences. The aim of the current study was to compare the surface tension and contact angle properties of different irrigation solutions used in endodontics, both on the dentin surface and within dentin tubules. METHODS: In this study, the contact angles and surface tensions of 5.25% sodium hypochlorite (NaOCl), 17% ethylenediaminetetraacetic acid (EDTA), 2% chlorhexidine (CHX), 5% boric acid (BA), 0.02% hypochlorous acid (HOCl), 0.2% chlorine dioxide (ClO2), Biopure MTAD, QMix solutions, and distilled water (control group) were measured. Measurements were conducted using a goniometer device (Attension Theta Lite Tensiometer, Biolin Scientific, USA), employing the sessile drop method for contact angle measurements on pre-prepared dentin surfaces, and the pendant drop method for surface tension. RESULTS: Contact angle measurements revealed no statistically significant differences between the contact angle values of MTAD, ClO2, and CHX or between NaOCl, QMix, BA, and HOCl (p > 0.05). However, EDTA exhibited a significantly greater contact angle than did MTAD, ClO2, CHX, NaOCl, QMix, BA, and HOCl (p < 0.05). Furthermore, the contact angle of dentin with distilled water was greater than that with all other solutions tested (p < 0.05). Surface tension measurements revealed that the surface tension values of QMix and MTAD were statistically similar (p > 0.05). CHX exhibited lower surface tension than distilled water and HOCl (p < 0.05), and it also had lower surface tension than ClO2, NaOCl, and BA (p < 0.05). Additionally, the surface tension of the samples treated with EDTA was greater than that of all other solutions tested (p < 0.05). CONCLUSION: The direct linear relationship between the surface tension of liquids and contact angles on different surfaces may not always hold true, and these values should be considered independently for each solution on various surfaces. Considering the contact angles and surface tension properties of irrigation solutions with root canal dentin, it can be suggested for clinical use that ClO2 could be recommended over NaOCl, and similarly, BA could be recommended over EDTA.


Assuntos
Dentina , Irrigantes do Canal Radicular , Tensão Superficial , Dentina/efeitos dos fármacos , Humanos , Hipoclorito de Sódio/farmacologia , Ácido Edético , Ácido Hipocloroso , Propriedades de Superfície
14.
Polymers (Basel) ; 16(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38891498

RESUMO

This study continues the discussion on the surface modification of polymers using an atmospheric pressure plasma (APP) reactor in air. These results complement prior research focusing on nonpolar polymers. Polymers, such as polyethylene terephthalate, polyetheretherketone, and polymethyl methacrylate, containing structurally bonded oxygen are studied, representing a range of properties such as oxygen content, crystalline/amorphous structure, polarity, functionality, and aliphatic/aromatic structure. APP induces superior wetting properties on the hydrophilic polymer surfaces with rapid and uniform modification within 0.5 s of exposure. The amorphous structures undergo additional modification for longer exposure. Moreover, the aliphatic chain structures require longer plasma exposure to reach surface modification equilibrium. The polar polymers reach a limit level of modification corresponding to a minimum water contact angle of about 50°. The surface polarity increases on average by a factor of approximately two. The equilibrium values of the adhesion work attained after post-processing recovery fall within a limited range of about 100-120 mJ/m2. The enhancement of surface functionality through the creation of oxidized groups primarily depends on the initial oxygen content and reaches a limit of about 40 at.% oxygen. The surface properties of the treated polar surfaces exhibit good stability, comparable to that of the previously tested nonpolar polymers.

15.
Materials (Basel) ; 17(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38893981

RESUMO

The present research investigated the voltage polarity asymmetry phenomenon based on dielectric wetting. In an ITO-hydrophobic layer-droplet setup, three reagents with different pH values (3.96, 7.0, and 10.18), two types of hydrophobic materials (AF1601 and 6%T6), and two different thicknesses (340 nm and 2.5 µm) of each material were systematically investigated. The results show that the thickness of the hydrophobic dielectric layer and the pH of the droplets had a significant impact on the droplet contact angle variation with the voltage. The contact angle on the thick hydrophobic dielectric layer followed the Lippmann-Young equation as the voltage changed. The angle of the thin hydrophobic dielectric layer was affected by its own properties and the type of droplet, which led to the occurrence of voltage polarity asymmetry of the electrowetting phenomenon. After further investigation of this phenomenon, it was found that it mainly accounted for the decrease in electric field strength at both ends of the droplet, which was caused by electrochemical reactions and changes in circuit resistance. The leakage current is an important indicator, and this phenomenon can be prevented by increasing the thickness of the hydrophobic dielectric layer.

16.
J Colloid Interface Sci ; 673: 836-846, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38908283

RESUMO

Covalent organic frameworks (COFs) have gained considerable interest as candidate photocatalysts for hydrogen evolution. In this work, we synthesized ß-keto-enamine-based COFs (TpPa-X, TpDB, and TpDTP) to explore the relations between structures and photocatalytic hydrogen evolution. COFs were divided into two groups: (1) TpPa-X with different substituents attached to the TpPa backbone and (2) COFs featuring diamine linkers of varied lengths (TpDB and TpDTP). Experiments and density functional theory (DFT) calculations show that moderate hydrophobicity is favorable for the photocatalytic hydrogen evolution process, and acceptable contact angles are anticipated to range from 65° to 80°. Naturally, there are comprehensive factors that affect photocatalytic reactions, and the regulation of different backbones and substituents can considerably affect the performance of COFs for photocatalytic hydrogen evolution in terms of electronic structure, specific surface area, surface wettability, carrier separation efficiency, and hydrogen dissociation energy. Results show that TpPa-Cl2 (TpPa-X, X  = Cl2) demonstrates the highest photocatalytic activity, approximately 14.51 mmol g-1h-1, with an apparent quantum efficiency of 4.62 % at 420 nm. This work provides guidance for designing efficient COF-based photocatalysts.

17.
Nanomaterials (Basel) ; 14(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38727331

RESUMO

Among different inorganic and organic polarizer elements, thin-film light polarizers occupy a special place because of their flexibility, ease of integration into any optoelectronic circuit, and good functioning in the visible and near-infrared spectral range and can compete with Glan and Nicolas volumetric prisms. This paper presents the results of a study on how carbon-based nanoparticles influence on the basic properties of a well-known PVA-based polymer matrix, using which it is possible to obtain good transparency for parallel light components. An accent is made on graphene oxide nanoparticles, which are used as PVA sensitizers. It was shown for the first time that the structuring of PVA with graphene oxides allows an increased transmittance of the parallel light component to be obtained, saving the transmittance of the orthogonal one. Moreover, the graphene network can increase the mechanical strength of such thin-film PVA-based polarizers and provoke a change in the wetting angle. These advantages make it possible to use graphene oxide-structured thin-film light polarizers based on a PVA matrix as an independent optoelectronic element. Some comparative results for polarizers based on PVA-C70 structures are shown as well.

18.
Materials (Basel) ; 17(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38730774

RESUMO

The study explores the novel use of oak bark (Quercus cortex) as a bio-filler in elastomeric composites, aligning with the global trend of plant-based biocomposites. Both modified and unmodified oak bark were investigated for their impact on the physicochemical properties of natural rubber (NR) composites. The bio-filler modified with n-octadecyltrimethoxysilane exhibited enhanced dispersion and reduced aggregates in the elastomeric matrix. NR composites containing more than 20 phr of unmodified and modified oak bark demonstrated an increased degree of cross-linking (αc > 0.21). Mechanical properties were optimal at 10-15 phr of oak bark and the sample with modified bio-filler (10 phr) achieved the highest tensile strength (15.8 MPa). Silanization and the addition of the bio-filler increased the hardness of vulcanizates. The incorporation of oak bark improved aging resistance at least two-fold due to phenolic derivatives with antioxidant properties. Hydrophobicity decreased with added bark, but silanization reversed the trend, making samples with a high content of oak bark the most hydrophobic (contact angle: 129°). Overall, oak bark shows promise as an eco-friendly, anti-aging filler in elastomeric composites, with modification enhancing compatibility and hydrophobicity.

19.
Materials (Basel) ; 17(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38730813

RESUMO

We present a surface modification technique that turns CuNi foam films with a high contact angle and non-sticking property into a sticky surface. By decorating with mesh-like biaxially oriented polypropylene (BOPP) and adjusting the surface parameters, the surface exhibits water-retaining capability even when being held upside down. The wetting transition process of droplets falling on its surface were systematically studied using the finite element simulation method. It is found that the liquid filled the surface microstructure and curvy three-phase contact line. Moreover, we experimentally demonstrated that this surface can be further applied to capture underwater air bubbles.

20.
Waste Manag ; 184: 120-131, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38815286

RESUMO

The recycling of spent lithium-ion batteries (LIBs) can not only reduce the potential harm caused by solid waste piles to the local environment but also provide raw materials for manufacturing new batteries. Flotation is an alternative approach to achieve the selective separation of cathode and anode active materials from spent LIBs. However, the presence of organic binder on the surface of hydrophilic lithium transition-metal oxides results in losses of cathode materials in the froth phase. In this study, plasma treatment was utilized to remove organic layers from cathode and anode active materials. Firstly, the correlations between plasma treatment parameters (e.g., input power, air flowrate, and treatment time) were explored and the contact angles of cathode and anode active materials were investigated by the response surface methodology. Secondly, differences in the flotation recoveries of cathode and anode active materials were enhanced with plasma modification prior to flotation, which is consistent with the contact angle measurement. Finally, the plasma-modification mechanisms of hydrophobicity of cathode and anode active materials were discussed according to Fourier Transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses. The proposed method could be a promising tool to enhance the flotation separation efficiency of cathode and anode active materials for the recycling of spent LIBs.


Assuntos
Fontes de Energia Elétrica , Eletrodos , Interações Hidrofóbicas e Hidrofílicas , Lítio , Reciclagem , Lítio/química , Reciclagem/métodos , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Resíduo Eletrônico
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