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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.

The potentiodynamic anodic polarization curves for the lead electrode were obtained in 0.1 mol L‐1 KOH solution in the absence and presence of C103‐ or C104‐ as aggressive ions at different concentrations. Lower concentrations of these ions have no significant influence on the passive film, while higher concentrations raise the active dissolution current density, and cause destruction of passivity and initiation of pitting corrosion. The critical pitting corrosion potential varies with the concentration of the aggressive ions according to sigmoidal curves. These curves were explained on the basis of the formation of passivitable, active and continuously propagagting pits depending on the range of the aggressive ion concentration. Additions of increasing concentrations of chromate, phosphate, sulphate and carbonate ions cause a shift of the critical pitting potential in the noble direction accounting for increase resistance to pitting attack (inhibition). The pitting corrosion potential varies with the concentration of the inhibitive ions, in the presence of a constant concentration of the aggressive ions, according to curves of sigmoidal shape. From these curves one can determine the minimum concentration of the inhibitive ions necessary for inhibition of pitting corrosion to occur.

The paper aims to study the dissolution of Al, Al‐3.84%Cu, Al‐5.22%Cu and Al‐11%Cu alloys in different concentrations of NaCl (10‐5‐10‐1 M).

The approach is to use open circuit potential (OCP) and potentiostatic polarization measurements.

Results obtained showed that, as the Cu content was increased in the Al‐Cu alloys, a steady state potential was rapidly reached. Addition of different concentrations of CuCl₂ to 0.5 M NaCl demonstrated that by increasing the concentration of CuCl₂ up to 2 ppm a greater increase in the OCP towards more anodic value occurred from the moment of immersion. Further increases in the concentration of CuCl₂, up to 600 ppm, exhibited the same behavior.

The results of the study reveal that cathodic current was controlled by the oxygen in solution, while the anodic current increased with increased Cu content in the alloy.

The electrochemical behaviour of zinc in different concentrations of Na₂SO₄ (pH = 6.0) was investigated using the potentiodynamic anodic polarization single sweep and cyclic voltammogram techniques. The anodic portion is characterized by one distinct peak corresponding to Zn(OH)₂ or ZnO. This is followed by a passive region up to a certain potential; the passive current suddenly rises steeply without any sign of oxygen evolution. This denotes the breakdown of the passive film and initiation of pitting corrosion. It was found that the breakdown potential depends on the sulphate concentration, type of aeration, scan rate, solution temperature and pH. The pitting initiation may be explained through the adsorption of SO₄^2– anion on the oxide film formed. This decreases the repair efficiency and causes further metal dissolution. From the cyclic voltammogram of zinc in different concentrations of Na₂SO₄, it was found that the change in the integrated anodic charge, Δq_a, which is taken as a measure of the extent of pitting, varies linearly with concentration of SO₄^2– anion.

The purpose of this paper is to develop technically efficient and economically effective sacrificial anodes that can be used for cathodic protection (CP) of pipelines in marine environment and fill the knowledge gap in the use of carbon anodes for CP.

A sacrificial anode was produced via sand casting by adding varying weight-percent of coal and ferrosilicon to a constant weight-percent of grey cast iron. The hardness of the produced anodes was evaluated using a Rockwell hardness tester. The microstructure of the anodes was observed with scanning electron microscope/energy-dispersive spectroscopy (SEM/EDS). X-ray diffraction (XRD) was used to study the phases present. A potentiostat was used to assess the corrosion behaviour of the produced anodes and mild steel in 3.5 Wt.% NaCl solution.

The SEM results showed that some anodes had interdendritic graphite formation, while others had pronounced graphite flakes. The EDS analysis showed carbon and iron to be the prominent elements in the anode. Anodes Bc, B2 and B5 with a corrosion rate of two order of magnitudes were observed to have similar dendritic structures. Anode B4 is the most electronegative with an Ecorr of −670.274 mV Ag/AgCl and a corrosion rate of 0.052475 mmpy. The produced anodes can be used to protect mild steel in the same environment owing to their lower Ecorr values compared to that of mild steel −540.907 mV Ag/AgCl.

Alloying has been majorly used to improve the efficiency of sacrificial anodes and to alleviate its setbacks. However, development of more technically efficient and economically effective sacrificial anodes via production of composite has not been exhaustively considered. Hence, this research focuses on the development of a carbon based anode by adding natural occurring coal and ferrosilicon to grey cast iron. The corrosion behaviour of the produced anode was evaluated and compared to that of mild steel in marine environment.

The purpose of this paper is to review the application of digital holography in studies of the corrosion of metallic materials.

Digital holography is used for in situ observation of the dynamic processes at the electrode | electrolyte interface and on the electrode surface during the corrosion dissolution of metallic materials.

Digital holography is an effect method to in situ observe the corrosion processes, and it can provide a direct experimental foundation for studying the corrosion mechanism.

Even though there are several challenges, digital holography will play a significant role in studying corrosion processes.

The purpose of this study is to investigate the state of undergraduate business statistics education in the Middle East and North Africa (MENA) and assess its alignment with the best practices in equipping business graduates with the knowledge and skills demanded by the labor market.

A survey of 108 instructors from 80 business schools in 17 MENA countries was conducted to gauge information on the delivery of business statistics courses. The survey results were benchmarked to a proposed framework for best practices in business statistics education.

The gap analysis identified deficiencies in the delivery of business statistics education in the region as compared to international best practices. This study revealed a need to revise statistics education as part of a comprehensive reform of business education with the aim to meet international quality standards in business education.

The study relied on the self-reported responses of business statistics instructors in MENA. One hundred eight questionnaires were completed, corresponding to a response rate of 40 per cent. Moreover, the study did not measure the effectiveness of teaching and learning in business statistics courses.

Recommendations from the study are intended to guide business statistics instructors in improving the quality of business statistics education through adopting more effective ways to enhance student learning experience and graduate employability.

This study is the first of its kind to investigate and assess the business statistics education in the MENA region.

The present study aims to investigate the effects of a number of demographic and academic factors, such as gender, age, nationality (Emirati vs non-Emirati), high school major (arts vs science) and high school score, on the academic performance – measured by overall grade point average – of undergraduate students majoring in statistics at United Arab Emirates University.

This study includes 188 undergraduate statistics students (142 female and 46 male) for the academic years 2012-2013 to 2015-2016. Descriptive and inferential statistics were used to analyze the collected data.

The results indicate that gender, age and nationality have no significant impacts on the academic performance of undergraduate students in statistics bachelor’s degree program, while high school major and high school score do.

This study had several limitations. First, only students of one university were included in this study, which would have limited the generalizability of the results. Second, the study focused on the impact of a limited number of factors on academic performance of undergraduate statistics students. But, the study has a number of implications for students, educators and university policy-makers.

The present study is the first attempt to explore the factors that might affect the academic performance of undergraduate students in statistics bachelor’s degree program in an Arabic setting.

Whilst English remains the language of global commerce, the role and outcomes of English language provision in English-medium higher education institutions in the Arab Gulf countries remains central to any discussion on graduate profile and the employability of graduates in the global marketplace. This paper describes the findings of research into English workplace communication skills amongst a sample of Bahrain employers and students at Bahrain Polytechnic. Using a mixed methods approach, data was gathered through telephone interviews, student workplace simulations and employer focus groups. Findings show that generic employability skills, channelled through English as a second or additional language, are highly valued by Bahrain’s employers. In particular, students need to market themselves as confident, knowledgeable individuals during the recruitment process and after recruitment, continuing to operate successfully in the sociolinguistic culture of their company. Consequently, it is concluded that English language training in higher education programmes needs to move from purely linguistic and degree-related content areas to a broader remit of English for communication purposes that covers both specialised discourse fields and broader generic employability skills and competencies.

The paper aims to investigate disclosure practices in the annual reports of Libyan banks in the run‐up to the opening of the nation's first stock exchange. Banks dominate this embryonic market but very little research has examined the extent (or determinants) of transparency achieved by these firms, an issue argued by Stiglitz and others to be crucial in the post‐crisis era. Currently, no detailed evidence of disclosure practices prior to the launch of the exchange exists, making an accurate assessment of the market's impact in this area impossible; the present study therefore contributes in this regard as well.

The study employs two main methods: a disclosure index‐based analysis of mandatory and overall disclosure levels; and panel regression analysis of the determinants of the overall disclosure levels.

The results suggest that while many items are disclosed on a regular basis, on average barely more than half of all possible items appear in the annual reports. As regards compliance with mandatory requirements, the figures are higher but, worryingly, begin to fall as the launch of the market neared. The results of panel‐data analysis suggest that the overall extent of disclosure is non‐random, instead reflecting the profits achieved by the banks concerned.

This paper is the first detailed analysis of disclosure practices in Libyan banks and the results suggest that market authorities should be looking for an improvement in the figures, in particular the reversal of a downward trend in compliance with mandatory requirements. The paper reports a link between profit level and disclosure propensity; this evidence might be of use to regulators charged with increasing disclosure levels in the future. More generally, the results provide a comparative basis on which to assess the effect of the market's launch on disclosure practices in Libya.