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The purpose of this paper is to prepare structural colors of fabrics coated with Silver/Zinc Oxide (Ag/ZnO) composite films by magnetron sputtering and analyze the relationship between the colors and the thickness of Zinc Oxide (ZnO) film in Ag/ZnO composite film and the photocatalytic property of the fabrics coated with Ag/ZnO composite film.

Ag/ZnO composite films deposited on polyester fabrics were prepared by magnetron sputtering technology. The structural colors of textiles coated with Ag/ZnO composite films and the relationship between the colors and Ag/ZnO composite films were analyzed, and the photocatalytic property of Ag/ZnO composite films was also discussed.

The results indicated that the colors varied with the thicknesses of the ZnO film in Ag/ZnO composite films. The reactive sputtering time of ZnO film was 5, 8, 10 and 14 min, respectively, and the colors of the corresponding fabrics were purple, blue, blue-green and yellow. Meanwhile, the polyester fabrics coated with Ag/ZnO composite films showed the excellent photocatalytic properties, and silver (Ag) films deposited under the ZnO films in Ag/ZnO composite films could also improve the photocatalytic activities of ZnO films, and the formaldehyde degradation rates was 77.5%, which was higher than the 69.9% for the fabrics coated only with the ZnO film.

The polyester fabrics coated with Ag/ZnO composite films not only created various structural colors using change the thicknesses of the ZnO film, but also achieved the multifuctionality, which will have a broad application prospect in textile fields.

This paper aims to investigate the structural, tribological and electrochemical properties of Ag₂O, ZnO, NiO coatings and Ag₂O/ZnO/NiO nanocomposite films deposited on commercially pure titanium.

Ceramic thin films (Ag₂O, ZnO, NiO coatings and Ag₂O/ZnO/NiO nanocomposite film) were deposited on commercially pure titanium (CP-Ti) substrate. Surface characterization of the uncoated and coated samples was made by structural surveys (scanning electron microscopic examinations and X-ray diffraction analyses), hardness measurements, tribological and corrosion experiments.

Results were indicated that sol-gel coatings improved the wear and corrosion resistance of CP-Ti, and the best results were seen at the nanocomposite coating. It may be attributed to its small grain size, high surface hardness and high film thickness.

This study can be a practical reference and offers insight into the influence of nanocomposite ceramic films on the increase of hardness, tribological and corrosion performance. Also, the paper displayed a promising approach to produce Ag₂O/ZnO/NiO nanocomposite coating on commercially pure titanium implants for biomedical applications.

This paper aims to investigate the effect of introducing nano-ceria (CeO₂) particles to the epoxy coatings on mild steel in natural seawater.

The epoxy–ceria nanoparticles were coated with mild steel using a wire-wound draw-down bar method. The effects of ceria nanoparticles on the corrosion resistance of epoxy-coated samples were analyzed using scanning electrochemical microscopy (SECM) and electrochemical impedance spectroscopy (EIS).

Localized measurements such as oxygen consumption and iron dissolution were observed using SECM in natural seawater in the epoxy-coated sample. The increase in film resistance (R_f) and charge transfer resistance (R_ct) values by the addition of nano-ceria particles in the epoxy coating was measured from EIS measurements after wet and dry cyclic corrosion test. Scanning electron microscope (SEM)/energy dispersive X-ray spectroscope (EDX) analysis showed that complex oxides of nano-ceria were enriched in corrosion products at a scratched area of the coated mild steel after corrosion testing. Focused ion beam-transmission electron microscope (FIB-TEM) analysis confirmed the presence of the nanoscale oxide layers of ceria in the rust of the steel.

The tip current at −0.70 V for the epoxy–CeO₂-coated sample decreased rapidly because of cathodic reduction of the dissolved oxygen. The increase in film resistance (R_f) and charge transfer resistance (R_ct) values by the addition of nano-ceria particles in the epoxy coating were measured from EIS measurements after wet and dry cyclic corrosion test.

The presence of complex oxide layers of nano-ceria layers protects the coated steel from rusting.

The use of this nano-ceria for corrosion protection is environment-friendly.

The results of this study indicated the significant effect of nano-ceria particles on the protective performance and corrosion resistance of the epoxy coating on mild steel. The dissolution of Fe²⁺ was lower in the epoxy–ceria nanoparticle-coated mild steel than that of the epoxy-coated mild steel resulting in a lower anodic current of steel. The increase in film resistance and the charge transfer resistance showed that the nano-ceria particles and the formation of complex oxides provide better barrier protection to the coating metal surfaces.

In this paper, two promising corrosion inhibitors based on natural and eco-friendly materials such as peanut fatty acids (PFA) were prepared and challenged with a common efficient commercial inhibitor. Two amino derivatives based on aliphatic and aromatic compounds such as 2-amino-2-methyl-1-propanol (AMP) and 2-amino-2-phenyl-1-propanol (APP), respectively, were used and reacted with PFA under controlled conditions to produce the corrosion inhibitors. The prepared inhibitors, namely, PFA-AMP (inhІ) and PFA-APP (inhІІ), were confirmed and characterized by Fourier transfer infrared spectroscopy, acid value determination and viscosity measurements.

First, different coating formulations free from any inhibitors were prepared and irradiated under different doses of electron beam source to select the best dose. Several concentrations of synthesized anticorrosion materials were then added to coating formulations to estimate them as anticorrosion materials for mild steel panels. Then, all formulations were coated and polymerized at a dose of 10 kGy. The corrosion tests, weight loss and water uptake were studied for all films after immersion in 3.5% sodium chloride. Moreover, the chemical and physico-mechanical properties were determined for all films.

The results exhibited that the different concentrations of two inhibitors did not show any significant change on the different properties of all films, and the best concentration, which gives the better protection for steel panels, was to be 1.0 g for two inhibitors.

It was found that the protection efficiency of the inhІ is better and higher than that of the inhІІ and also of the commercial inhibitor with the following order: inhІ > commercial inhibitor > inhІІ.

This study aims is to evaluate the environmentally friendly turmeric as a corrosion inhibitor for mild steel in a simulated seawater corrosion medium such as a 3.5% NaCl solution. To accomplish this, different proportions of turmeric (0.3, 0.6, 0.9 and 1.5%) were added to solvent-free epoxy-acrylate resin-based coating formulations. Then, all the formulations were sonicated and coated as thin films on different substrates; these coated films were then polymerized under a dose of 10 kGy of electron beam (EB) radiation.

Various properties of all cured coating films such as Fourier transform infrared spectroscopy, water contact angle, thermogravimetric analysis and scanning electron microscopy were studied, in addition to their physical, chemical and mechanical properties. Turmeric was then evaluated in these formulations as an anticorrosion agent for mild steel in 3.5% NaCl. The different corrosion-resistant properties of all EB-cured coating films were evaluated by open circuit potential measurements, rust degree, blistering, adhesion loss at X-cut and weight loss measurements.

The results showed that most of the formulations are homogeneous, especially at low concentrations of turmeric, and their films have high-performance properties.

It was also found that the formulation containing 0.6% of turmeric per 100 g of coating was considered the best formulation as it gave the highest protection to the mild steel plates with no negative effects on the chemical and physical properties of their films.

The purpose of this paper is to investigate the interfacial nanostructures and the adhesions of the stainless steel (S.S) coating to the polyurethane (PU) and polyvinyl chloride (PVC) leathers.

PU leather and PVC leather deposit S.S nano-films on the surface of PU and PVC leathers in this study. The interfacial nanostructures were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The experimental results revealed that the surface roughness of the substrates had extremely important influence on the morphology of nano-films. The adhesions of the S.S coating to the PU and PVC leathers were investigated by the peel-off test.

The results showed that the adhesive performance of the S.S nano-films coating on PVC leather was better than that on the substrate of PU leather. Moreover, a weight loss of per peeling force calculating formulation is proposed to determine the bonding strength between the S.S films and the substrates.

In this paper, influence of different substrates on surface morphology of S.S coating was studied by SEM and AFM. Moreover, the weight loss of per peeling force calculating formulation was used to discuss the bonding strength between the S.S coating and the substrates. The research methods presented in this paper are of innovation significance to a certain extent.

Banana is an important tropical fruit with high demand in the market. The ripe fruits are less resistant to transport making logistics difficult. Moreover, as a climacteric fruit, it has a short post-harvest shelf life. Edible coatings/films, including active substances, have been used as an alternative for preserving fruits and vegetables during post-harvest period. The purpose of this study was to evaluate the incorporating clove essential oil on the properties of cassava starch films and their effect on the post-harvest quality of different banana varieties.

Cassava starch films incorporating clove essential oil were developed and the films were characterized with respect to moisture, thickness, solubility, water vapor permeability (WVP), biodegradability, color and in vitro antifungal activity. Cultivars such as Prata-Anã, Grand Nine, BRS Tropical and BRS Conquista were coated with cassava starch, cassava starch film with clove essential oil (CSEO) and polyvinyl polychloride (PVC). The quality of fruits was monitored during eight storage days using mass loss, total soluble solids content (TSS) and titratable acidity (TTA).

Incorporation of clove essential oil significantly increased film thickness, reduced moisture content, solubility and WVP (p < 0.05) and did not affect the biodegradability and color of the films. The essential oil incorporated films showed antifungal activity against the fungi Colletotrichum gloeosporioides and Colletotrichum musae, but not against the yeast Saccharomyces bourladii. CSEO and PVC coating were more efficient in reducing the mass loss, SS content and TTA of the coated fruits in all varieties studied. Both CSEO and PVC coatings improve the quality attributes such as TSS and TTA and reduced mass loss, of the banana varieties such as Prata-Anã, Grand Nine, BRS Tropical and BRS Conquista during storage.

The active film with essential oil showed antifungal activity and essential oil can be incorporated into other food systems. This study approaches a new possibility of film coating with essential oil for a banana that showed minimum weight loss and satisfactory quality and increased shelf life. This film coating demonstrates biodegradable characteristics that could be eco-friendly and sustainable to consumers.

The purpose of this paper was to investigate the anti-corrosion behavior of polypyrrole (PPy) films in different states and presence of alumina nanoparticles synthesized by galvanostatic electropolymerization on stainless steel (SS) electrodes in an artificial seawater solution using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS).

The electrochemical measurements were used to examine the effects of PPy and its nanocomposite on the corrosion behavior of SS type 316L in artificial seawater. A standard electrochemical cell with three electrodes was used for the measurements. The electrochemical response of the coated electrodes in the doped and the undoped state was compared with that of a bare electrode. Corrosion rate information was obtained by the Tafel extrapolation method, where the intersection point of a cathodic and an anodic polarization curve provides both the corrosion potential and the corrosion current. EIS measurements confirmed the potentiodynamic and open circuit potential (OCP) results. The microstructure of the obtained films was investigated by scanning electron microscopy.

The results showed that the coated polymer films shifted the electrode potential toward more positive potentials, but this shift did not lead to passivation. However, a notable synergy was observed between PPy undoped film, oxygen reduction and iron dissolution. The potential of the SS remained in the active dissolution region, and it was not possible to produce a passive oxide layer in this region. PPy separates the metal dissolution process from the oxygen reduction process. This would prevent the local pH increase at the metal surface and subsequent delamination. The polarization curves, EOCP and impedance measurements showed that PPy undoped/Al₂O₃ layers show promise as good candidates for the corrosion protection of reactive metals.

This paper presents that electrodes coated with undoped PPy synthesized in the presence of dodecyl sulfate anions and Al₂O₃ nanoparticles offered a noticeable enhancement of protection against corrosion processes.

The main purpose of this paper was to evaluate the influence of the zein coating containing essential oils on the sensory characteristics of sodium-reduced mozzarellas.

Mozzarellas were prepared by dipping in brine containing 5, 10, 15 or 20% of NaCl (w/v) that correspond, respectively, to 25, 50, 75 and 100% of NaCl content used in industry. These salted mozzarellas and another one, unsalted, were coated by an edible zein film added with 3% of a mixture of thyme and garlic essential oils (1:1). They were subjected to sensory analysis in relation to salty taste and overall impression. The mozzarella without salt reduction (20% NaCl w/v), coated or uncoated with the edible film, was also subjected to the analysis of water loss and microbiological quality, in order to evaluate the impact of this film on product quality.

The zein coating added with oils did not compromise the sensory acceptance of the mozzarella prepared with up to 50% of salt reduction. Water loss and microbial growth were lower in zein-coated mozzarella than in uncoated mozzarella. These results showed that this film could be applied as natural additive, contributing to the microbiological and sensory characteristics of the mozzarella.

This paper contributes to reducing the lack of studies in relation to new technologies for food preservation and sodium reduction. In addition, the zein coating containing essential oils can be tested on other food categories.

The purpose of this paper is to study the effect of thermal treatment on the corrosion protection of steel by using poly(3-hexylthiophene) (P3HT) and P3HT/PS(polystyrene) or P3HT/PMMA(polymethyl methacrylate) blends coatings in sulfuric acid solution.

The polymer coatings were thermally treated at two different temperatures (100 and 200°C, respectively) and were compared with the polymer coatings dried at room temperature in their application as protective coatings against corrosion of A36 steel. The corrosion resistance of polymer coatings-covered steel substrates was evaluated by using potentiodynamic polarization curves and linear polarization resistance.

At 25 and 100°C, polymer coatings showed a better protection of the A36 steel, and the corrosion rate diminished in three orders of magnitude with regard to the bare steel. Morphological study showed that the increased temperature benefited the integration of the two polymeric phases; however; the temperature of 200°C affected the film quality, generated cracks and holes, which affected the barrier properties of the coatings.

The research involved the synthesis and physicochemical characterization of the polymeric coatings (P3HT, PS/P3HT y PMMA/P3HT), as well as their application as coatings in the steel to prevent corrosion. The effect of thermal treatment of the protective coatings on steel corrosion was studied.

This paper aims to contribute to reducing the problem of metal corrosion through the use of polymer coatings.

Today, majority of metal surfaces are subject under the protection to prevent a very common phenomenon, that is corrosion. Corrosion is the result of chemical reactions that occur between a metal or a metal alloy and its environment. Corrosion creates a degradation of the material that has an impact on some economic, environmental and even social aspects, here the great importance of its protection.

It is shown in this study that the P3HT coating provides better corrosion protection of the A36 steel than the PS and PMMA coatings. However, mixtures of P3HT with PMMA and PS protected the steel from corrosion by two and three orders of magnitude similar to the simple P3HT coating. Polymer blends improved adhesion to the substrate and mechanical property of the coating, and in addition, the polymer blends made cheaper coating.