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The purpose of this paper is to evaluate the effect of micro-nano mixed super-hydrophobic structure on corrosion resistance and mechanism of magnesium alloys.

A super-hydrophobic surface was fabricated on AZ91 and WE43 magnesium alloys by laser etching and micro-arc oxidation (MAO) with SiO₂ nanoparticles coating and low surface energy material modification. The corrosion resistance properties of the prepared super-hydrophobic surfaces were studied based on polarization curves and immersion tests.

Compared with bare substrates, the corrosion resistance of super-hydrophobic surfaces was improved significantly. The corrosion resistance of super-hydrophobic surface is related to micro-nano composite structure, static contact angle and pretreatment method. The more uniform the microstructure and the larger the static contact angle, the better the corrosion resistance of the super-hydrophobic surface. The corrosion resistance of super-hydrophobic by MAO is better than that of laser machining. Corrosion of super-hydrophobic surface can be divided into air valley action, physical shielding, pretreatment layer action and substrate corrosion.

The super-hydrophobic coatings can reduce the contact of matrix with water so that a super-hydrophobic coating would be an effective way for magnesium alloy anti-corrosion. Therefore, the corrosion resistance properties and mechanism of the prepared super-hydrophobic magnesium alloys were investigated in detail.

This study aims to improve the corrosion resistance of TA2-welded joints by superhydrophobic surface modification using micro-arc oxidation technology and low surface energy substance modification.

The microstructure and chemical state of the superhydrophobic film layer were analyzed using scanning electron microscopy, energy dispersive X-ray spectroscopy, three-dimensional morphology, X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared absorption spectroscopy. The influence of the superhydrophobic film layer on the corrosion resistance of TA2-welded joints was investigated using classical electrochemical testing methods.

The characterization results showed that the super hydrophobic TiO₂ ceramic membrane was successfully constructed on the surface of the TA2-welded joint, and the construction of the super hydrophobic film greatly improved the corrosion resistance of the TA2-welded joint.

The superhydrophobic TiO₂ ceramic membrane has excellent corrosion resistance. The micro nanostructure in the superhydrophobic film can intercept air to form an air layer to prevent the corrosion medium from contacting the surface, thus, improving the corrosion resistance of the sample.

This paper aims to explore the mechanism of the slip phenomenon at macro/micro scales, and analyze the effect of slip on fluid flow and heat transfer, to reduce drag and enhance heat transfer.

The improved tangential momentum accommodation coefficient scheme incorporated with Navier’s slip model is introduced to the discrete unified gas kinetic scheme as a slip boundary condition. Numerical tests are simulated using the D2Q9 model with a code written in C++.

Velocity contour with slip at high Re is similar to that without slip at low Re. For flow around a square cylinder, the drag is reduced effectively and the vortex shedding frequency is reduced. For flow around a delta wing, drag is reduced and lift is increased significantly. For Cu/water nanofluid in a channel with surface mounted blocks, drag can be reduced greatly by slip and the highest value of drag reduction (DR) (67.63%) can be obtained. The highest value of the increase in averaged Nu (11.78%) is obtained by slip at Re = 40 with volume fraction φ=0.01, which shows that super-hydrophobic surface can enhance heat transfer by slip.

The present study introduces and proposes an effective and superior method for the numerical simulation of fluid/nanofluid slip flow, which has active guidance meaning and applied value to the engineering practice of DR, heat transfer, flow control and performance improvement.

This study aims to produce a superhydrophobic fabric surface with a layered rough structure and which are resistant to droplet adhesion. Polydimethylsiloxane (PDMS) systems doped with stearic acid modified titanium dioxide (SA-TiO₂) nanoparticles was sprayed onto the surface of cotton fabric.

This experiment therefore uses a simple method to prepare superhydrophobic textiles by spraying SA-TiO₂ particles mixed with PDMS onto the surface of cotton fabrics. The effects of the ratio of stearic acid to TiO₂, spraying times and tension on the apparent morphological structure and hydrophobic properties of the cotton fabric were investigated.

The results showed that the stearic acid-modified TiO₂ nanoparticles were hydrophobic and more uniformly dispersed in the PDMS solution. When the modification ratio of stearic acid to TiO₂ was 3:5, the water contact angle of cotton fabric was 155.48° and sliding angle was 6.67° under the applied tension for three times of spraying, showing superhydrophobicity. The fabric shows super hydrophobic and anti-adhesive properties to a wide range of liquids such as cola, dyeing liquids, tea, milk and simulated blood. The surface tension of the liquid shows a negative correlation with its adhesion to the fabric.

The SA-TiO₂ and PDMS were applied to the fabric surface by spraying, which not only gave the fabric superhydrophobic properties, but also created anti-adhesion to a wide range of droplets.

The superhydrophobic cotton fabrics prepared by this method showed good anti-adhesive behavior to common stains and simulated blood and can be used in the development of medical protective textiles.

Modification of TiO₂ with stearic acid to prepare SA-TiO₂ with excellent hydrophobic properties, which was mixed with PDMS to make suspensions. Fluorine-free superhydrophobic fabrics were prepared by spraying method. It also exhibited excellent anti-adhesive properties against blood, providing a reference for the preparation of self-cleaning and anti-adhesive surgical gowns.

This paper is based on the simulation of wind tunnel experiment for better understanding and predicting the behavior of PET fabric in the wind tunnel. This software calculates the drag force of fabric, illustrates pressure in the surrounding of airfoil and velocity of wind in the tunnel during different angles of attack (0°, 45° and 90°). The paper aims to discuss these issues.

The sol-gel method was applied for the synthesis of silica nano particles. So, PET fabric was coated with precursor (Tetra ethyl ortho silicate) solution first and the process continued on PET fabric. The morphology of obtained hydrophobic fabric samples and their surface roughness was observed and determined by atomic microscopes (AFM and SEM). Experimental data were used for simulation and modeling, and then results were interpreted.

It was concluded that the surface roughness and its amount can play a significant role in the drag reduction of PET fabric, and surface roughness can change the boundary layer from laminar to turbulent.

At 45 degrees angle of attack, larger boundary layer separation results in a large increase in the drag force. This model is useful for predicting flow behavior in the experimental wind tunnel.

Carbon nanotube-based architectures have increased the scientific interest owning to their exceptional performance rendering them promising candidates for advanced industrial applications in the nanotechnology field. Despite individual CNTs being considered as one of the most known strong materials, much less is known about other CNT forms, such as CNT arrays, in terms of their mechanical performance. The paper aims to discuss these issues.

In this work, thermal CVD method is employed to produce VA-MWCNT carpets. Their structural properties were studied by means of SEM, XRD and Raman spectroscopy, while their hydrophobic behavior was investigated via contact angle measurements. The resistance to indentation deformation of VA-MWCNT carpets was investigated through nanoindentation technique.

The synthesized VA-MWCNTs carpets consisted of well-aligned MWCNTs. Static contact angle measurements were performed with water and glycerol, revealing a rather super-hydrophobic behavior.

The structural analysis, hydrophobic behavior and indentation response of VA-MWCNTs carpets synthesized via CVD method are clearly demonstrated.

The purpose of this study is to prepare a state-of-the-art review on advanced ceramic materials including their fabrication techniques, characteristics, applications and wettability.

This review paper presents the various types of advanced ceramic materials according to their compounding elements, fabrication techniques of advanced ceramic powders as well as their consolidation, their characteristics, applications and wetting properties. Hydrophobic/hydrophilic properties of advanced ceramic materials are described in the paper with their state-of-the-art application areas. Optical properties of fine ceramics with their intrinsic characteristics are also presented within. Special focus is given to the brief description of application-based manipulation of wetting properties of advanced ceramics in the paper.

The study of wetting/hydrophobicity/hydrophilicity of ceramic materials is important by which it can be further modified to achieve the required applications. It also makes some sense that the material should be tested for its wetting properties when it is going to be used in some important applications like biomedical and dental. Also, these advanced ceramics are now often used in the fabrication of filters and membranes to purify liquid/water so the study of wetting characteristics of these materials becomes essential. The optical properties of advanced ceramics are equally making them suitable for many state-of-the-art applications. Dental, medical, imaging and electronics are the few sectors that use advanced ceramics for their optical properties.

This review paper includes various advanced ceramic materials according to their compounding elements, different fabrication techniques of powders and their consolidation, their characteristics, various application area and hydrophobic/hydrophilic properties.

Durability of textile materials under wet conditions has become very important in recent years. The water repellency performance of fabrics should be maintained in the seam areas. The purpose of this paper is to analyze the effect of water repellent agents and sewing threads on the seam and water repellency performance properties of woven fabrics.

100 percent polyester woven fabrics were treated with three different water repellent finishing agents (silicone, fluorocarbons with 6 and 8 carbons) and then sewn with different sewing threads (unfinished/water repellent finished polyester/cotton corespun and polyamide filament). Afterwards, mechanical properties, seam performance and water repellency properties of these materials were measured.

The effect of finishing which was statistically significant on seam strength only in warp direction was significant on seam elongation and efficiency in both warp and weft directions. Seam strength, seam efficiency, seam slippage and seam pucker of fabrics sewn with polyamide threads were higher than others. The fluorocarbons applied to the fabrics gave higher water repellency values than silicones. In addition, as the chain length increased in fluorocarbons, water repellency performance increased. Sewing process reduced water resistance of fabrics; however, water repellent finish applied to the threads increased water resistance of fabrics.

As a result of the literature review, it was seen that water repellency property of a wear were studied in only seamless areas of fabrics. Originality of this study is that the water repellency properties are also analyzed in the seam areas of the fabrics and evaluated together with the seam performance characteristics.

Milk is often referred to as the ultimate food because it meets the nutritional needs of infants, children and adults alike. It is a rich source of protein, fat, sweetness, vitamins and minerals. Because of its widespread usage as a healthy dairy product, the issue of milk adulteration is of global significance. The increasing frequency of fraudulent methods in the dairy business raises concerns about its purity and quality.

A study was conducted and reviewed that looked at several approaches for detecting milk adulteration during the past 15 years. This study examines the current state of research and analyzes recent advances in development.

There are ways and technology available that can effectively put an end to the abhorrent practice of milk adulteration.

This research takes a unique approach, focusing on the application of milk adulteration. It provides an overview of milk adulteration detection and investigates the effectiveness of biosensors in identifying common milk adulterants.

The textile industry is evolving toward nanotechnology, which provides materials with self-cleaning properties. This paper aims to provide a thorough explanation of the green synthesis and mechanism of ZnO nanoparticles, with prospective applications of zinc oxide nanoparticles (ZnO NPs) in self-cleaning textiles.

This review introduces a green mechanism for the synthesis of ZnO NPs using plant extracts, their self-cleaning properties and the mechanisms of physical, chemical and biological self-cleaning actions for textile applications.

ZnO NPs are among the several nanoparticles that are beneficial for self-cleaning textiles because of their exceptional physical and chemical properties, although review publications addressing the use of ZnO NPs in textiles for self-cleaning are uncommon. These results indicate that the plant-synthesized ZnO NPs display excellent biological, physical and chemical self-cleaning properties, the mechanism of which involves photocatalysis, surface roughness and interactions between ZnO NPs and bacterial surfaces.

Nanoformulations of plant-synthesized ZnO have been reviewed to achieve promising self-cleaning textile properties and have not been reviewed earlier.