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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 study is to prepare copper oxide nanoparticles (CuO NPs) in an easy and efficient way using a natural and environmentally friendly substance like ascorbic acid. Various concentrations of these nanoparticles were then added to solvent-free coating formulations to produce highly hydrophobic, corrosion-resistant and antimicrobial hybrid coatings. These hybrid formulations were also used to coat the spent fuel casks for their integrity.

The hybrid coated films were then characterized by X-ray diffraction, Fourier transform infrared spectroscopy (FT-IR), water contact angle and Scanning electron microscope (SEM). In addition, different measurements, namely, mechanical, physical, chemical, thermal, corrosion tests, open circuit potential and antimicrobial activity of these hybrid films were performed.

The results showed that the copper oxide was prepared at nanometer scales with good homogeneity and diffusion in the epoxy acrylate matrix. It also showed that some hybrid coatings have high corrosion resistance, strong hardness, excellent water resistance, remarkable antimicrobial activity and high thermal stability compared to virgin epoxy acrylates.

The formula containing 0.5% CuO NPs was found to provide the highest corrosion protection and antimicrobial activity for mild steel in 3.5% sodium chloride (NaCl).

This paper aims to develop a simple and efficient plasma technology for the production of copper (I) oxide with the ability to control the morphology and size of Cu₂O particles. To achieve this goal, the phase composition of the precipitate formed was estimated, the composition and size of the obtained particles were determined and Pourbaix diagrams were constructed.

An integrated approach combining thermodynamic calculations and experimental research methods is used. The constructed Pourbaix diagram makes it possible to suggest the phase composition of the sediment. The use of cyclic voltammetry made it possible to establish the mechanism of deposit formation on the cathode during the treatment of the solution with contact nonequilibrium low-temperature plasma. The resulting product was examined using X-ray phase analysis and scanning electron microscopy.

The article presents the results of theoretical and experimental studies on the synthesis of copper (II) oxide. The influence of the parameters of plasma-chemical synthesis on the shape and phase composition of the deposits formed has been studied.

A plasma-chemical technology for obtaining copper oxide in the form of single crystals of a regular faceted shape is proposed. The mechanism of formation of copper oxide has been established by cyclic voltammetry. The constructed Pourbaix diagrams show the area of existence of the product.

This study aims to investigate the corrosion inhibitor effect of migrating corrosion inhibitor (MCI) on Q235 steel in high alkaline environment under cathodic polarization.

This study investigated the electrochemical characteristics of Q235 steel with and without MCI by polarization curve and electrochemical impedance spectroscopy. Besides, the surface composition of Q235 steel under different environments was analyzed by X-ray photoelectron spectroscopy. In addition, the migration characteristic of MCI and the adsorption behavior of MCI under cathodic polarization were studied using Raman spectroscopy.

Diethanolamine (DEA) and N, N-dimethylethanolamine (DMEA) can inhibit the increase of Fe(II) in the oxide film of Q235 steel under cathodic polarization. The adsorption stability of DMEA film was higher under cathodic polarization potential, showing a higher corrosion inhibition ability. The corrosion inhibition mechanism of DEA and DMEA under cathodic polarization potential was proposed.

The MCI has a broad application prospect in the repair of damaged reinforced concrete due to its unique migratory characteristics. The interaction between MCIs, rebar and concrete with different compositions has been studied, but the passivation behavior of the steel interface in the presence of both the migrating electric field and corrosion inhibitors has been neglected. And it was investigated in this paper.

This study aims to focus on how reactive diluents with mono- and di-functionalities affect the properties of resin formulation developed from bioderived precursors. A hydroxyethyl methacrylate (HEMA) terminated urethane acrylate oligomer was synthesized and characterized to study its application in stereolithography 3D printing with different ratios of isobornyl acrylate and hexanediol diacrylate.

Polyester polyol was synthesized from suberic acid and butanediol. Additionally, isophorone diisocyanate, polyester polyol and HEMA were used to create urethane acrylate oligomer. Fourier transform infrared spectroscopy and ¹H NMR were used to characterize the polyester polyol and oligomer. Various formulations were created by combining oligomer with reactive diluents in concentrations ranging from 0% to 30% by weight and curing with ultraviolet (UV) radiation. The cured coatings and 3D printed specimens were then evaluated for their properties.

The findings revealed an improvement in thermal stability, contact angle value, tensile strength and surface properties of the product which indicated its suitability for use as a 3D printing material.

This study discusses how oligomers that have been cured by UV radiation with mono- and difunctional reactive diluents give excellent coating characteristics and demonstrate suitability and stability for 3D printing applications.

In the present work, under severe conditions of an inert atmosphere and high temperature, epoxidized natural rubber (ENR) with 25 per cent epoxidation level reacts with different aliphatic amine compounds such as ethyl amine (EA), propyl amine (PA) and butyl amine (BA) to prepare ENR/EA, ENR/PA, ENR/BA compounds as, respectively. The produced compounds were characterized by Fourier transform infrared spectroscopy and oxirane oxygen content determination. Different concentrations of the produced compounds were added to epoxy and urethane acrylate coating formulations to evaluate them as corrosion inhibitors for mild steel under UV irradiation. Corrosion resistance tests and weight loss measurements of the coated steel panels were made. It was found that coating formulations containing the prepared ENR/EA compound could protect metal surface from corrosion, and corrosion inhibitors efficiency of the prepared compounds were arranged as follows: ENR/EA > ENR/PA > ENR/BA. The optimum concentrations for all inhibitors which give the best inhibition efficiency for corrosion are 0.4-0.6 phr.

Corrosion scratch tests were carried out according to ASTM D 1,654-92 (2000). The weight loss of coated steel was measured according to ASTM D 2,688-94 (1999). The measurement of film hardness was carried out with a Wolff–Wilborn pencil hardness tester according to ASTM D 3,363 (2000).

It was found that coating formulations containing the prepared ENR/EA compound could protect metal surface from corrosion and corrosion inhibitors efficiency of the prepared compounds were arranged as follows: ENR/EA > ENR/PA > ENR/BA. The optimum concentrations for all inhibitors are 0.4-0.6 g/100g coating.

A highly efficient and economically corrosion inhibitors for mild steel were prepared from ENR and series of aliphatic amines.

The rate of copper dissolution in the presence of phosphoric acid‐alcohol mixtures was studied by measuring the limiting current density which represents that the rate of electropolishing is decreased by increasing phosphoric acid concentration, electrode height, and mole fraction of alcohol. Thermodynamic parameters are calculated. The rotating disk electrode is being used as a tool to study the influence of organic solvent addition on the rate of electropolishing of copper. Different reaction conditions such as temperature, speed of rotation of copper disk, the physical properties of solution are studied to obtain a dimensionless correlation between all these parameters. The data can be correlated by the following equations: Sh = 1.835 (Sc)^0.33 (Re)^0.36 (for ethylene glycol) Sh = 1.25 (Sc)^0.33 (Re)^0.5 (for glycerol) It is obvious that the exponent in the two cases denotes a laminar flow mechanism.

The study aims to investigate the anticorrosion performance of epoxy coatings using modified cerium oxide (CeO₂) by terephthalic acid (CeO₂-t) and fumaric acid (CeO₂-f) as corrosion inhibitors.

The chemical state of CeO₂-t, and CeO₂-f were analyzed by infrared radiation (IR) and X-ray diffraction (XRD). The effect of different inhibitors on the coating properties was analyzed by neutral salt spray tests (NSST) and electrochemical impedance spectroscopy (EIS).

The results of IR and XRD illustrate that the modification of CeO₂ was successful, and fumaric acid underwent a ring-opening reaction with epoxy resin (EP) in the coatings. The results of NSST and EIS showed that the coatings containing CeO₂-f exhibited the best anticorrosion performance.

CeO₂ is an effective inhibitor of the organic coatings. When surface modified, it is chemically bonded to EP, enhancing the anticorrosion performance of EP.

The effects of incorporation of Locusta migratoria (LM) powder at different levels (0, 1, 2, 3, 4 and 5%) on nutritional, qualitative and sensory properties of baked breads were investigated.

Chemical composition, mineral elements and functional properties of wheat flour, LM powder and their binary mixture systems were determined. The breads were assayed for proximate composition, minerals, amino acids profile, physical characteristics and sensorial properties.

LM powder have relatively high levels of protein (51.97% db), fat (23.15% db) and fibers (13.76% db). LM powder presented significantly (p ≤ 0.05) greater water absorption capacity (WAC), oil absorption capacity(OAC), emulsion activity (EA) and foam capacity (FC) as compared to wheat flour. Blending wheat flour with various levels of LM powder significantly (p ≤ 0.05) improved the functional properties of binary mixture systems. Protein, fat, fiber and ash contents of bread samples significantly increased with the addition of LM powder. No significant differences (p ≤ 0.05) were recorded in specific volume between control breads and those breads containing LM powder up to 2%. Breads fortified with LM powder contained higher values of essential amino acids than the limits of FAO/WHO pattern, with exception of lysine. Sensory evaluation results showed that bread samples with the addition of LM powder at levels 1–4% had high overall acceptability.

Limitations of our study are the lack of approved and professional programs about management, collection, harvesting, processing, marketing and consumption of edible insects; therefore, these results should be generalized implications for industry. This present study, therefore, provides useful data to support public health nutrition aimed at improving the nutritional health of populations through the promotion of bakery products enriched with LM powder.

The main findings of this study indicated that the addition of 1–4% of LM powder into wheat flour enhanced sensory and nutritional properties of produced breads.

It is concluded that the addition of LM powder improves the nutritional and sensorial properties of the produced bread when the wheat flour is substituted with 1–4% of LM powder.