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To evaluate the effect of some tetrazole compounds as corrosion inhibitors of copper in HNO₃ at various temperatures.

1‐phenyl‐5‐mercapto‐1,2,3,4‐tetrazole (PMT) was selected as the best inhibitor among the tetrazole compounds tested. Gravimetric and electrochemical techniques were conducted.

PMT was an excellent inhibitor for copper in acid. Its efficiency attained 97.5 per cent and decreased slightly with temperature.

The inhibition efficiency increased with the concentration of PMT to reach 97.5 per cent at 10⁻³ M. Good agreement between the various methods explored was observed. Polarisation measurements also showed that PMT acted as a mixed inhibitor.

The efficiency of PMT increased with the concentration but decreased with rise of temperature in the 298‐333 K range. As such, PMT could be used in chemical cleaning and pickling processes.

The originality of this work was the finding of an efficient inhibitor (PMT) having a nearly 100 per cent efficiency.

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.

Refers to previous research on the firm characteristics which affect the relationship between unexpected returns and unexpected earnings to suggest that multinationality may proxy for all of them. Develops mathematical models to investigate the effect of multinationality and applies them to 1995‐1999 US data on multinational firms. Describes the methodology and presents the results, which suggest that firms with relatively more multinationality have smaller, less significant earnings response coefficients and vice versa. Concludes that multinationality is a good proxy for firm size, quality of preannouncement information, earnings predictability etc.

The objective of this paper is to present the existing state of research relating to the steel industries.

This research looks at the link between corporate social responsibility (CSR) and environmental performance, considering the immediate mutual interaction and the potential mediation of specific variables like green innovation and green human resource management (GHRM).

Partial least squares path modeling was used to investigate a sample of 460 respondents in multinational textile manufacturing companies in Ethiopia.

The findings of this study reveal a direct and positive relationship between CSR and environmental performance. In addition, the researchers observed an indirect effect on the relationship by using GHRM and green innovation as mediators.

The study applied a cross-sectional methodology, and experts are not sure that CSR, GHRM, and green innovation in Textile manufacturing companies provide the same results over time. Consequently, future researchers can utilize the same method of investigation to see if outcomes change or stay the same over time. Second the study was conducted in Ethiopia. As a resut, it is possible that our study results will not be generalizable to other emerging nations. We propose expanding research to include more nations with developing markets.

Executives of textile manufacturing companies can adopt the present study framework of performance in developing economies to reduce waste, pollution and air emissions, and conserve water, energy and nonrenewable resources that enhance environmental performance.

The discovery of the present research makes significant contributions to the literature on the impact of CSR on environmental performance as a pioneering study by incorporating CSR, GHRM, green innovation and environmental performance under one research model in an emerging economy context.

A high-boron concentration solution is commonly used as a buffer system in the study of metal corrosion. However, it is impossible to apply such a high-boron concentration solution in the practical use because of the high-cost and environment problem.

In this study, the authors examined the effect of a low dosage of boric acid and borax mixture as inhibitor to suppress carbon steel corrosion in 1 M HCl solution by weight loss experiment and various electrochemistry methods (potentiodynamic polarization curves, electrochemical impedance spectra and electrochemical noise).

Results showed that the borate mixture exhibited an anodic-type inhibitor characteristic, when the total boron concentration was in the range of 100∼150 mg L⁻¹. The passivation performance derived from the formation of a passive film with and FeBO₃-FeOOH structure, whose integrity and thickness gradually increased with the increasing boron concentration.

Low boron solution could protect carbon steel from the attraction of corrosive ions by forming a passive film with Fe-O-B structure. The findings broaden the application range of borate solution in the industry.

This paper aims to investigate the corrosion inhibition effects of indole-3-carbaldehyde and 2-methylindole on mild steel in 1 M HCl solution.

Indole-3-carbaldehyde and 2-methylindole as corrosion inhibitors of mild steel in 1 M HCl solution were investigated by polarisation and electrochemical impedance spectroscopy (EIS). Adsorption isotherm and mechanism were calculated. Quantum chemical calculations were used to find out a correlation between electronic structure of inhibitors and inhibition efficiency. Changes in the properties of metal surface in HCl solution in the presence of inhibitors were studied by contact angle measurements.

Polarisation results revealed inhibitors could reduce cathodic and anodic reactions rates on metal surface. EIS analysis showed that inhibition efficiency of indoles increases by increasing the inhibitors’ concentration; maximum inhibition efficiency was 95 and 94 per cent in solutions containing 1 mM indole-3-carbaldehyde and 2-methylindole, respectively. Inhibitors’ adsorptions on metal surface were confirmed by analysing the exposed metals’ surface through contact angles measurements. The adsorption of inhibitors was found to follow Langmuir isotherm. Quantum chemical calculations showed that a more positively charged benzene ring in the structure of two indole-based inhibitors would lead to higher adsorption to metal.

This research was carried out to understand the effects of two different functional groups (-C=O, -CH3) with different induction effects on the indole structure and on inhibition efficiency of corrosion inhibitors with the purpose of using these components in industrial application as acid wash solutions to etch and remove rusts from metal surfaces.

The effects of the addition of poly(4‐vinylpyridine) (P4VP) and its derivative poly(4‐vinylpyridine poly‐3‐oxide ethylene) (P4VPPOE) on the corrosion of Cu60‐Zn40 in 0.5M HNO₃ have been investigated by potentiodynamic and weight loss measurements. Both of the studied polymers decrease the corrosion rate. Their inhibition efficiency (E%) increases with the concentration. The maximum of inhibition was obtained for P4VPPOE (100 per cent at 10^–5M). E% obtained from cathodic Tafel plots and weight loss methods were in good agreement. The inhibitors were adsorbed on the Cu60‐Zn40 surface according to the Frumkin adsorption isotherm model. P4VPPOE acts as a cathodic inhibitor and its efficiency is temperature independent.