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This paper aims to reduce environment pollution caused by benzotriazole. The authors chose one of the best inhibitors from 2-aminobenzimidazole, 2-methylbenzimidazol, 2-mercaptobenzimidazole and benzimidazole in combination with benzotriazole.

The electrochemical measurement indicated that 2-methylbenzimidazol had the best inhibition behavior. Then, it was mixed with benzotriazole. Techniques such as field emission scanning electron microscopy, atomic force microscopy, Raman spectroscopy and optical contact angle measurements were used.

The results showed that the inhibition efficiency was up to 99.98%, when the mixture concentration was 20 mmol/L and the molar ratio 1:1.

1-benzotriazole was mixed with 2-methylbenzimidazol for the first time. During the exist of methyl, 2-methylbenzimidazol has the better inhibition; this point was ignored by researchers.

This paper aims to evaluate the inhibitive effect and adsorption behavior of 5-(ethylthio)-1H-tetrazole (EHT) and 5-(benzylthio)-1H-tetrazole (BHT) on copper in a sulfur-ethanol system.

Evaluation was carried out using electrochemical measurement and surface analysis techniques. Measurements of static friction coefficient by scanning electron microscopy and contact angle analysis were applied and finally confirmed the existence of the adsorbed film. The inhibitive mechanism of the two compounds was evaluated by means of quantitative calculation and molecular dynamics simulation. The friction coefficient of corrosion surface before and after adding corrosion inhibitor was determined through static friction coefficient measurements.

The electrochemical measurement indicated that the most effective concentration of two corrosion inhibitors was 70 mg L^–1, while the inhibition efficiency of that was EHT > BHT. The friction coefficient data showed that the addition of corrosion inhibitor reduced the roughness of the corrosion surface. Adsorption behavior of two inhibitors followed the Langmuir’s adsorption isotherm and was attributed to mixed-type adsorption. The results of quantitative calculation and molecular dynamics simulation showed that tetrazole rings of the two inhibitors and its connected S atoms were adsorbed on Cu(111) surface in parallel.

The corrosion inhibition performance of two tetrazolium derivatives in a sulfur-ethanol system was studied by combining experiments with theory, which provided a theoretical basis for the future research.

This paper aims to evaluate the inhibition efficiency of thiadiazole derivatives, such as 2,5-dimercapto-1,3,4-thiadiazole (DMTD), 5-methly-2-mercapto-1,3,4-thiadiazole (MMTD) and 2,5-dithiododecyl-1,3,4-thiadiazole (DDTD), in 50 mg/L hydrogen sulfide for silver strip.

Evaluation was carried out by corrosion-inhibiting test, electrochemical measurement and surface analysis techniques. 3D surface profiler, atom force microscopy, scanning electron microscopy and energy-dispersive X-ray analysis were applied and finally confirmed the existence of the adsorbed film.

The electrochemical measurement showed that the inhibition efficiency increases with increasing inhibitor concentration in 50 mg/L hydrogen sulfide solution, while the corrosion rate and the corrosion current decrease. Weight-gained measurements also indicated that inhibitor decreases the corrosion rate in the studied solution. The adsorption of DMTD and MMTD on the silver surface obeys Temkin’s adsorption isotherm, but the adsorption of DDTD follows Langmuir’s adsorption isotherm. That means that the inhibition mechanism is different between DMTD, MMTD and DDTD. The ΔG0_ad values of DMTD, MMTD and DDTD were −37.47, −37.29 and −38.69 kJ/mol, respectively. It showed that there was an adsorption bond between silver surface and inhibitor, and the adsorption belongs to chemical adsorption.

The inhibitors have an excellent inhibition efficiency, and the best inhibition efficiency is 91.76 per cent. Inhibitors can effectively inhibit metal corrosion in the oil and gas.

This paper aims to investigate the impact of corporate culture on stock price crash risk and explore the underlying mechanisms.

This paper uses a novel firm-level culture measure of Li et al. (2020), which evaluates corporate culture from the perspectives of integrity, teamwork, innovation, respect and quality. Using a sample of 4,017 US firms from 2001 to 2018, this paper uses panel data regressions to explore the impact of corporate culture on stock price crash risk.

This paper finds that among five cultural dimensions, integrity reduces crash risk and quality increases crash risk. The mitigating effect of integrity culture on crash risk is concentrated among firms with a strong incentive or ability to hoard bad news. The exacerbating effect of quality culture on crash risk is concentrated among firms with low managerial flexibility.

This paper helps investors and regulators to understand the determinants of stock price crash risk, which facilitates investors’ wealth management and stabilizes social welfare.

To the best of the authors’ knowledge, this is the first study that uses time-varying firm-level measure of corporate culture to investigate its impact on stock price crash risk, contributing to the literature on the determinants of crash risk. Besides, this is the first study that explores the possible mechanism of managerial flexibility in influencing stock price crash risk.