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Ferrofluids are aqueous or non-aqueous solutions with colloidal particles of iron oxide nanoparticles with high magnetic characteristics. Their magnetic characteristics enable them to be controlled and manipulated when ferrofluids are exposed to magnetic fields. This study aims to inspect the features of unsteady stagnation point flow (SPF) and heat flux from the surface by incorporating ferromagnetic particles through a special kind of second-grade fluid (SGF) across a movable sheet with a nonlinear heat source/sink and magnetic field effect. The mass suction/injection and stretching/shrinking boundary conditions are also inspected to calculate the fine points of the features of multiple solutions.

The leading equations that govern the ferrofluid flow are reduced to a group of ordinary differential equations by applying similarity variables. The converted equations are numerically solved through the bvp4c solver. Afterward, study and discussion are carried out to examine the different physical parameters of the characteristics of nanofluid flow and thermal properties.

Multiple solutions are revealed to happen for situations of unsteadiness, shrinking as well as stretching sheets. Greater suction slows the separation of the boundary layers and causes the critical values to expand. The region where the multiple solutions appear is observed to expand with increasing values of the magnetic, non-Newtonian and suction parameters. Moreover, the fluid velocity significantly uplifts while the temperature declines due to the suction parameter.

The novelty of the work is to deliberate the impact of mass suction/injection on the unsteady SPF through the special second-grade ferrofluids across a movable sheet with an erratic heat source/sink. The confirmed results provide a very good consistency with the accepted papers. Previous studies have not yet fully explored the entire analysis of the proposed model.

The aim of this paper is to investigate inhibition of copper corrosion by 3,5‐bis(2‐thienyl)‐4‐amino‐1,2,4‐triazole (2‐TAT) in 1 M HCl and 0.5 M H₂SO₄.

Potentiodynamic polarization curves and electrochemical impedance measurements were carried out on copper in 1 M HCl and 0.5 M H₂SO₄ containing various concentrations of 2‐TAT, and the effects of temperature were also investigated.

As an efficient inhibitor, 2‐TAT behaves better in 1 M HCl than in 0.5 M H₂SO₄. 2‐TAT can be classified as cathodic‐type corrosion inhibitor in 1 M HCl and acts as relatively mixed type in 0.5 M H₂SO₄. Activation energies in the presence and absence of 2‐TAT were obtained by measuring the temperature independence of corrosion current. Adsorption of the inhibitor on the copper surface was found to obey the Langmuir adsorption isotherm.

This inhibitor could have application in industries where hydrochloric acid solutions are used to remove scale and salts from copper surfaces and may render dismantling unnecessary.

The results from this paper showed that 2‐TAT could be considered as a suitable inhibitor for copper in acidic media.

The pitting corrosion of copper in chloride solution has been studied using potentiostatic polarisation and surface analysis techniques. X‐ray photoelectron spectroscopy (XPS) results enabled conclusions to be drawn about the nature of the film formed in different chloride concentrations. In dilute chloride solutions (C≤10⁻³ M), XPS proved the existence of Cu₂O film on the copper surface. It was found that, depending on the chloride content, pitting of copper was evident only after the formation of a protective film of Cu₂O. A current‐time trend plot showed the onset of fluctuations, which were dependent on the NaCl content. On the other hand, introduction of O₂ into the solution during prepolarisation time period increased the current value of the fluctuations at the same concentration of NaCl in comparison with the freely aerated solution. These results, together with the surface analysis, confirm the role of chloride ion on the mechanism of pitting attack on copper metal.

This study aims to develop and evaluate epoxy coatings enhanced with micaceous iron oxide (MIO) and nanocrystalline aluminum (Al) particles, focusing on improving mechanical and corrosion-resistance properties for extended durability.

Three epoxy coatings were fabricated by incorporating 1, 2 and 3 wt% MIO with a fixed 2 wt% of ball-milled Al particles. The coatings were thoroughly characterized using field emission scanning electron microscopy, thermogravimetric analysis, hardness and scratch resistance tests, nanoindentation and electrochemical impedance spectroscopy (EIS). The EIS measurements in 3.5 wt% NaCl solution were performed over various immersion periods (1 h, 7, 14, 21 and 30 days) to study the coatings’ corrosion behavior.

The coating with 2 wt% MIO exhibited superior corrosion resistance across all immersion periods, outperforming the other formulations. Although corrosion resistance initially declined after seven days of immersion, it improved significantly after extended exposure (14–30 days) due to the formation of protective oxide layers on the coating surface. The combination of MIO and nanocrystalline Al also enhanced the mechanical properties of the epoxy coatings, delivering improved hardness, scratch resistance and overall stability.

This study highlights the synergistic effect of MIO and nanocrystalline Al particles in epoxy coatings, demonstrating their potential to enhance both mechanical performance and long-term corrosion resistance. The research offers valuable insights into the formulation of advanced epoxy coatings for applications requiring durability under harsh conditions.

The purpose of this study is to explore how different types of environmental claims may affect the communication effectiveness of environmental advertising. Two two moderating variables include the perceived eco‐friendly image of the originating country and consumer involvement.

The examination involves the analysis of the responses of 1,200 subjects in Shanghai, China, to mock advertisements containing environmental claims using a 2 x 3 factorial design.

Environmental claims enhance the communication effectiveness of advertisements for both high‐ and low‐involvement services. For high‐involvement services, substantive environmental claims generate more favorable attitudinal responses than do associative environmental claims.

This research focused on a single Chinese city and on two service categories with contrasting degrees of involvement. While such a confinement can enhance the internal validity of the findings, their external validity has yet to be established.

These findings suggest that marketers should adopt a situational perspective by taking into account environmental claim type, country disposition, the degree of environmental consciousness of their target consumers, and service type when designing their environmental advertising campaigns.

Although a number of previous studies have focused on the application of environmental claims to advertise products, similar investigation into how these claims may help advertise services is virtually non‐existent. In this respect, the present study can be viewed as the first empirical work devoted to closing this research gap.

Adoption of sustainability principles is crucial for construction project delivery, and various parameters are being used as a yardstick for its measurement. This chapter discusses profit as one of the parameters used to determine the success of a sustainable construction project. It explains such issues as the nature and important of construction industry and its product (construction project), meaning of sustainable construction as well as meaning of profit and what its entails in construction. It reviews the value of profit as a measure of success for a construction project and also encourages the need for planning and analysis of all activities involved on a construction project in relation to its environment so as to validate the profit as a measure of project success.

This study aims to prevent mild steel (MS) against corrosion in 0.5 M HCl solution, 2-amino-4-methoxy-6-methyl-1,3,5-triazine was used. The effectiveness of the compound as a corrosion inhibitor was studied via electrochemical, surface and theoretical calculation techniques.

For concentrations ranging from 0.5 to 10.0 mM, almost similar polarization resistances were obtained from electrochemical impedance spectroscopy (EIS) and linear polarization resistance tests. It also investigated inhibitive activity of 2-amino-4-methoxy-6-methyl-1,3,5-triazine on the steel surface using scanning electron and atomic force microscope instruments. Langmuir adsorption is the best matched isotherm for the adsorption of the inhibitor to the steel surface.

EIS method was used to determine inhibition efficiency, which was determined to be 95.7% for 10.0 mM inhibitor containing acid solution. Density functional theory’s predictions for quantum chemistry agreed well with the other experimental results.

The methods used in this study are effective and applicable; the used organic inhibitor is 2-amino-4-methoxy-6-methyl-1,3,5-triazine; and protective effectiveness is important, which is crucial for the task of MS corrosion prevention.

This study aims to investigate the inhibition effect of a newly synthesized1,2,3-triazole containing a carbohydrate and imidazole substituents, namely, 1-((1-((2,2,7,7-tetramethyltetrahydro-5H-bis([1,3]dioxolo)[4,5-b:4′,5′-d]pyran-5-yl)methyl)-1H-1,2,3-triazol-4-yl)methyl)-1H-benzo[d]imidazole (TTB) on the corrosion of mild steel in aerated 1 M H₂SO₄.

The authors have used weight loss measurement, potentiodynamic polarization, electrochemical impedance spectroscopy, FT-IR studies, scanning electron microscopy analysis and energy dispersive X-ray (EDX) spectroscopy techniques.

It is found that, in the working range of 298-328 K, the inhibition efficiency of TTB increases with increasing concentration to attain the highest value (92 per cent) at 2.5 × 10⁻³ M. Both chemisorption and physisorption of TTB take place on the mild steel, resulting in the formation of an inhibiting film. Computational methods point to the imidazole and phenyl ring as the main structural parts responsible of adsorption by electron-donating to the steel surface, while the triazol ring is responsible for the electron accepting. Such strong donating–accepting interactions lead to higher inhibition efficiency of TTB in the aqueous working system.

This work is original with the aim of finding new acid corrosion inhibitors.

To correlate the inhibitory effect of triazole compounds on the corrosion of copper in HCl at various temperatures by semi‐empirical molecular orbital theory.

Two triazoles were selected as the best inhibitors among the triazole compounds tested. Gravimetric and electrochemical measurements were conducted.

Correlation between inhibition efficiency and calculation of molecular orbital of triazole compounds was obtained. Cu(I)‐triazole complex formation was confirmed by UV spectroscopy.

The calculation of energetic levels of molecular orbital may be a tool to explain the classification of inhibitor efficiency.

The theoretical calculation is a complementary mean to selecting an efficient inhibitor among a given series. Good agreement between the experimental methods explored and theoretical calculations was observed.

The originality of this work was the finding of the correlation between energetic levels of orbital molecular and inhibitor efficiency of triazole compounds. The confirmation of the formation of Cu(I)‐triazole by UV‐visible spectroscopy was also new.

Inorganic oxide addition can be synergistically beneficial in organic coatings if it can impart anti-corrosion properties and also act as an additive to enhance physical and/or chemical properties. The aim of this study was to evaluate the anti-corrosion benefits of nano nickel zinc ferrite (NZF) in the polymer film.

The time-dependent anti-corrosion ability of NZF (0.12-1.0 per cent w/w NZF/binder), applied on API 5L X-80 carbon steel, was characterized by electrochemical techniques such as open circuit potential, electrochemical impedance spectroscopy, linear polarization resistance and potentiodynamic. Characterization of corrosion layer was done by removing coatings after 216 h of immersion in 3.5 per cent w/v NaCl. Optical microscopy, field emission scanning electron microscopy and X-ray diffraction techniques were used to characterize the corroded surface.

Corrosion measurements confirm the electrochemical activity by metallic cations on the steel surface during corrosion process which results in improvement of anti-corrosion properties of steel. Moreover, surface techniques show compact corrosion layer coatings and presence of different metallic oxide phases for nanocomposite coatings.

The suggested protection mechanism was explained by the leaching and precipitation of metallic ion on the corroded surface which in turn slowed down the corrosion activity. Furthermore, improvement in barrier properties of rubber-based coatings was confirmed by the enhanced pore resistance. This work indicates that along with a wide range of applications of NZF, anti-corrosion properties can be taken as an addition.