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Article
Publication date: 13 September 2021

Jose-Gonzalo Gonzalez-Rodriguez, Andres Carmona Hernandez, E. Vázquez-Vélez, A. Contreras-Cuevas and Jorge Uruchurtu Chavarin

This paper aims to use an imidazole-based n-ionic Gemini surfactant derived from palm oil to inhibit the sulfide stress corrosion cracking of a supermartensitic stainless steel.

87

Abstract

Purpose

This paper aims to use an imidazole-based n-ionic Gemini surfactant derived from palm oil to inhibit the sulfide stress corrosion cracking of a supermartensitic stainless steel.

Design/methodology/approach

The slow strain rate testing technique, hydrogen permeation tests and potentiodynamic polarization curves have been used.

Findings

Addition of the inhibitor below the critical micelle concentration (CMC) decreased the corrosion current density (icorr), but not enough to avoid embrittlement due to the entry of hydrogen into the steel. Instead, the addition of the inhibitor close to the CMC decreased the icorr, suppressed the entry of hydrogen and inhibited the sulfide stress cracking of steel. Finally, the addition of inhibitor above the CMC led to a slight increase of icorr and promoted localized corrosion, however, the sulfide stress cracking of steel was inhibited.

Originality/value

A green sulfide stress corrosion cracking inhibitor of a supermartensitic stainless steel has been obtained.

Details

Anti-Corrosion Methods and Materials, vol. 68 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 August 2003

E.A. Ashour and H.S. Hegazy

The stress corrosion cracking (SCC) susceptibility of type 316 stainless steel in 3.4 per cent NaCl with different concentrations of thiosulphate solution and the inhibiting…

406

Abstract

The stress corrosion cracking (SCC) susceptibility of type 316 stainless steel in 3.4 per cent NaCl with different concentrations of thiosulphate solution and the inhibiting effect of benzotriazole (BTAH) on SCC were investigated by slow strain rate technique. The addition of BTAH to test solution produces an inhibitive effect on the stress corrosion susceptibility (S). The mode of cracking changed from brittle transgranular to ductile failure at higher concentrations of BTAH. Some electrochemical measurements were obtained to complement the SCC measurements. The results indicated that the inhibitive action of BTAH can be attributed to its adsorption and inhibiting the anodic dissolution of the alloy by the effect of blocking the active sites on the alloy surface.

Details

Anti-Corrosion Methods and Materials, vol. 50 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 February 2003

A.A. El Warraky

The corrosion behaviour of copper in dilute HCl solution of pH 1.8‐2, in the absence and presence of different additives of Na2S, was studied by open circuit potential…

582

Abstract

The corrosion behaviour of copper in dilute HCl solution of pH 1.8‐2, in the absence and presence of different additives of Na2S, was studied by open circuit potential measurement, scanning electron microscopy and polarisation techniques. A complete covering of the surface with the strongly chemisorbed HS is achieved at ≥10 ppm Na2S concentration. The addition of different concentrations of ethylene diamine (EDA) to HCl of pH 1.8‐2 promoted the dissolution rate, due to an increase in autocatalytic dissolution at the Cu metal surface. However, the synergistic inhibition effect between EDA and Na2S, resulting from the adsorption of HS on the Cu metal, facilitated the adsorption of EDA.

Details

Anti-Corrosion Methods and Materials, vol. 50 no. 1
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 12 September 2018

Shuya Li, Zhengqi Gu, Taiming Huang, Zhen Chen and Jun Liu

The purpose of this paper is to develop a two-way coupling approach for investigating the aerodynamic stability of vehicles under the combined effect of crosswind and road…

151

Abstract

Purpose

The purpose of this paper is to develop a two-way coupling approach for investigating the aerodynamic stability of vehicles under the combined effect of crosswind and road adhesion.

Design/methodology/approach

The author develops a new two-way coupling approach, which couples large eddy simulation with multi-body dynamics (MBD), to investigate the crosswind stability on three different adhesion roads: ideal road, dry road and wet road. The comparison of the results obtained using the traditional one-way coupling approach and the new two-way coupling approach is also done to assess the necessity to use the proposed coupling technique on low adhesion roads, and the combined effect of crosswind and road adhesion on vehicle stability is analyzed.

Findings

The results suggest that the lower the road adhesion is, the larger deviation a vehicle generates, the more necessary to conduct the two-way coupling simulation. The combined effect of the crosswind and road adhesion can decrease a vehicle’s lateral motion on a high adhesion road after the disappearing of the crosswind. But on a low adhesion road, the vehicle tends to be unstable for its large head wind angle. The vehicle stability in crosswind on a low adhesion road needs more attention, and the investigation should consider the coupling of aerodynamics and vehicle dynamics and the combined effect of crosswind and road adhesion.

Originality/value

Developing a new two-way coupling approach which can capture the complex vehicle structures and the road adhesion with MBD model and the completed fluid filed structure with CFD model. The present study might be the first study considering the coupling of crosswind and low adhesion road. The proposed two-way coupling approach will be useful for researchers who study vehicle crosswind stability.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 28 no. 8
Type: Research Article
ISSN: 0961-5539

Keywords

Available. Content available
1240

Abstract

Details

Archnet-IJAR: International Journal of Architectural Research, vol. 13 no. 3
Type: Research Article
ISSN: 2631-6862

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Article
Publication date: 1 July 2006

Qun‐Jie Xu, Guo‐Ding Zhou, Hui‐Feng Wang and Wen‐Bin Cai

The aim of this paper is to study the inhibition effect of environmentally friendly inhibitors; polyaspartic acid (PASP), Na2WO4 and the complex of PASP and Na2WO4 for brass and…

500

Abstract

Purpose

The aim of this paper is to study the inhibition effect of environmentally friendly inhibitors; polyaspartic acid (PASP), Na2WO4 and the complex of PASP and Na2WO4 for brass and Cu30Ni alloy (B30) corrosion in simulated cooled water solutions.

Design/methodology/approach

The inhibiting effect was investigated in simulated cooled water solutions by potentiodynamic polarization (DC) and electrochemical impedance spectroscopy.

Findings

The results indicated that PASP and Na2WO4 both had an inhibition effect. A desirable inhibition effect was shown for brass and B30 corrosion at a PASP concentration of 15 mg/L. The best inhibition effects for Na2WO4 appeared at 10 mg/L for B30 corrosion and at 20 mg/L for brass, respectively. The combination of PASP and Na2WO4 showed a synergistic effect. The optimum ratio of PASP to Na2WO4 was 6:1 at the total inhibitor concentration of 20 mg/L.

Originality/value

This paper has for the first time showed that the two environmentally friendly inhibitors PASP and Na2WO4 had an inhibition effect for brass and B30 corrosion and the complex of PASP and Na2WO4 had good synergistic effect for brass and B30 corrosion in simulated cooled water solutions.

Details

Anti-Corrosion Methods and Materials, vol. 53 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 8 April 2014

Gaiqing Zhao, Qin Zhao, Xiaobo Wang and Weimin Liu

The purpose of this paper is to study a novel Mannich adduct of benztriazole-containing diphenylamine (coded as BD) and its anti-oxidation properties as an additive in two typical…

155

Abstract

Purpose

The purpose of this paper is to study a novel Mannich adduct of benztriazole-containing diphenylamine (coded as BD) and its anti-oxidation properties as an additive in two typical synthetic ester-based oils.

Design/methodology/approach

The anti-oxidation properties in two typical synthetic ester-based oils were evaluated in detail, using rotating pressure vessel oxidation test. The tribological properties of BD in synthetic ester-based oil (A51) were also tested with Optimal SRV-I oscillating friction and wear tester at atmosphere.

Findings

The results of tests demonstrated that the novel BD compound is, indeed, a high-performance anti-oxidation additive that was able to remarkably improve the oxidation stability of synthetic ester-based oils, when it was added at only 0.5 per cent concentration and compared with the base oils containing 0.5 per cent of the commercial available antioxidant additives such as 2, 6-di-tert-butyl-4-methylphenol and octyl-butyl diphenylamine. A plausible mechanism of exceptional synergistic anti-oxidation was proposed.

Originality/value

This paper first investigated the anti-oxidation properties and mechanisms of the compound with the structure of BD, which can be very useful and would promote the application of BD antioxidant in the lubricant industry.

Details

Industrial Lubrication and Tribology, vol. 66 no. 3
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 February 2023

Mohamed Hegazy, Mohamed Samy El-Deeb, Hosny Ibrahim Hamdy and Yasser Tawfik Halim

This paper aims to examine the effect of the auditors’ burnout determinates on audit quality and performance. It also analyses whether the demographic characteristics of gender…

2038

Abstract

Purpose

This paper aims to examine the effect of the auditors’ burnout determinates on audit quality and performance. It also analyses whether the demographic characteristics of gender, age group, education and job positions affect auditors’ decisions for burnout, audit quality and performance.

Design/methodology/approach

A questionnaire was distributed on a sample of auditors in the top ten auditing firms in an emerging market including the Big 4. Factor analysis, correlation matrix and structural equation modeling were used for the analysis of the collected data and testing the developed hypotheses.

Findings

The results show that burnout has negative consequences for both the auditor and the auditing firm. While good organizational climate has a negative significant association with audit quality, nonethical decisions and audit performance, role clarity has positive significant association with the audit quality and performance and has an insignificant association with nonethical decisions. Also, turnover intention has significant positive association with nonethical decision, audit quality and performance.

Originality/value

This research is among the first to focus on auditor’s burnout determinates on audit quality and performance in an emerging market characterized by different socioeconomic, political and cultural factors compared with those of developed markets. Auditors, regulators and professional policymakers can benefit from the results of this research.

Details

Journal of Accounting & Organizational Change, vol. 19 no. 5
Type: Research Article
ISSN: 1832-5912

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Article
Publication date: 22 August 2022

Mohamed Abdel Aziz Hegazy, Rasha El-Haddad and Noha Mahmoud Kamareldawla

This paper aims to investigate how auditors’ characteristics affect key audit matters (KAMs) in the new audit report. It also provides an understanding of the effect of the…

1736

Abstract

Purpose

This paper aims to investigate how auditors’ characteristics affect key audit matters (KAMs) in the new audit report. It also provides an understanding of the effect of the COVID-19 pandemic on different audit reporting decisions and audit quality in specific industries.

Design/methodology/approach

The paper uses a survey based on actual audit case studies extracted from the management letters of clients in an audit firm with international affiliation to test the proposed hypotheses. Kruskal–Wallis and Mann–Whitney tests are conducted to analyze variance in responses among different groups of auditors regarding their selection of audit report sections required for each audit matter. The Wilcoxon signed rank test analyses difference in the auditors’ responses pre- and post-COVID-19 implications.

Findings

Most of the developed hypotheses were only partially accepted where industry specialization, professional qualifications of the auditors and the effects of COVID-19 had some effects on the ability of auditors to recognize and disclose KAMs. Auditor position is the most factor that significantly influenced the recognition of KAMs in the new audit report resulting in higher audit quality. This was specially the case with auditors specializing in manufacturing and financial institutions.

Originality/value

The current research illustrates that during the pandemic, auditors were more effective in recognizing KAMs compared to other audit matters, thus enhancing users’ confidence in both the audit and the financial reporting processes. The results are useful to regulators and auditors as they provide a better understanding of the factors that may impact communicating KAMs in the new audit report under COVID-19.

Details

Managerial Auditing Journal, vol. 37 no. 7
Type: Research Article
ISSN: 0268-6902

Keywords

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Article
Publication date: 1 February 2022

Mohamed Abdel Aziz Hegazy and Samar Salama

The purpose of this paper is to investigate the effect of qualitative materiality factors on auditors’ assessment of materiality and the determination of the type of the auditors’…

1414

Abstract

Purpose

The purpose of this paper is to investigate the effect of qualitative materiality factors on auditors’ assessment of materiality and the determination of the type of the auditors’ reports. This paper also analyzes whether differences in personal characteristics of auditors can influence their use of qualitative materiality factors in assessing material misstatements.

Design/methodology/approach

A questionnaire and experimental case studies were undertaken to determine whether differences in personal characteristics of auditors can influence their degree of reliance on qualitative factors in assessing the materiality of detected misstatements. Descriptive and statistical tests were used to analyze the data collected.

Findings

The results of this paper show that qualitative materiality factors strongly influence the auditor’s materiality judgments. However, no significant differences were found regarding the effects of auditors’ personal characteristics on the degree to which they rely on the qualitative factors in their materiality judgments. Also, in certain situations, auditors considered factors other than the income for assessing certain misstatements as material and consequently modified their audit reports.

Originality/value

This paper examines the influence of qualitative factors on auditors’ materiality judgments and develops a list of qualitative factors to be considered by auditors when assessing materiality. It also concludes that the nature of misstatement is the least important qualitative factor considered by auditors when assessing materiality of detected misstatements and that the existence of more explicit or standardized qualitative materiality guidelines would lead to a more uniform judgment among auditors.

Details

Managerial Auditing Journal, vol. 37 no. 3
Type: Research Article
ISSN: 0268-6902

Keywords

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