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This paper seeks to examine the fatigue properties of HVOF sprayed Inconel‐625 coating of steel substrate before and after the aqueous corrosion.

Workpieces were cut from steel sheets. After chemical and ultrasonic cleaning, workpiece surfaces were sand‐blasted and HVOF sprayed Inconel‐625 coated. The coated and un‐coated surfaces were subjected to the aqueous corrosion tests for one and three weeks. After the completion of the corrosion tests, fatigue properties of the workpieces were examined.

Stainless steel coated workpieces demonstrated excellent fatigue life resistance versus coated carbon steel workpieces. Stainless steel workpieces apparently have a high‐cycle fatigue represented by in excess of 1.50 million cycles without cracking, thereby assuring a high‐fatigue life. The carbon steel specimens have low‐cycle fatigue and consequently a short fatigue life. In addition, high velocity impacting of splats on to the workpiece enhances the hardness of the surface. This, in turn, improves fatigue properties at the interface, particularly for stainless steel workpieces.

The tests can be extended to include the duplex treated workpieces such as the laser treatment of surface after HVOF sprayed coating. This enhances the bonding of the coating through thermal integration of the coating and the base substrate material.

The results can be used to assess the HVOF sprayed coatings.

This paper provides information on the fatigue behavior of HVOF sprayed coatings when subjected to the cyclic load and offers practical help for the researchers and scientists working in the coatings area.

To examine the tensile properties of high velocity oxy‐fuel (HVOF) sprayed Inconel 625 coating of steel substrate before and after the aqueous corrosion.

Workpieces were cut from steel sheets. After chemical and ultrasonic cleaning, workpiece surfaces were sand blasted and HVOF sprayed Inconel 625 coated. The coated and un‐coated surfaces were subjected to the aqueous corrosion tests for one and three weeks. After the completion of the corrosion tests, tensile properties of the workpieces were examined.

The workpieces subjected to a three weeks static corrosion environment fail at a lower load than the untreated workpiece due to high stiffness. The defect sites in the coating and at the interface act as stress risers and contribute substantially crack initiation and propagation in the coating. Under increasing tensile load in the plastic region, the substrate material can no longer support the coating. This results in extended cracking and gradually spalling of the coat. When the local critical stress for crack propagation is reached, elongated cracks occur, which in turn initiates splitting separation between the adjacent zones in the coating. The shear deformation of the adjusted zones results in the total failures of the coating.

The tests can be extended to include the duplex treated workpieces such as the laser treatment of surface after HVOF sprayed coating. This enhances the bonding of the coating through thermal integration of the coating and the base substrate material.

The results can be used to assess the HVOF sprayed coatings.

This paper provides information on mechanical behavior of HVOF sprayed coating when subjected to the tensile force and offers practical help for the researchers and scientists working in the coating area.

Evidence suggests that corporate entrepreneurship (CE), namely, innovativeness, risk-taking and corporate venturing, enhances a firm’s performance. However, the study of CE in developing markets – particularly in Egypt – is still new and undeveloped. The literature stresses the importance of incorporating environmental factors into the study of CE. Therefore, the purpose of this study is to examine the relationship between CE, environmental jolts (unexpected abrupt environmental events such as the Arab Spring) and the firm’s financial performance. Based on the periods before and after the series of anti-government protests known as the Arab Spring, this paper argues that after an environmental jolt, CE will negatively affect financial performance.

This study analyzes and correlates CE, environmental jolts and firm performance in Egypt for a period over 10 years (from 2007 through 2016) using a sample of 94 manufacturing firms listed on the Egyptian Stock Exchange. Data were manually collected through archival/secondary data using financial and accounting information from the annual reports released by the firms. These reports were downloaded from the firms’ webpages and the Egyptian Exchange website.

The main results of this paper indicate that environmental factors play a role in the effect of CE on firm performance. Using the 2011 Arab Spring as a quasi-natural experiment, this paper finds that CE’s effect on firm performance is higher pre-jolt and lower post-jolt.

This study provides useful implications for managers and practitioners. Firms need to find new ways of allocating their resources to help provide innovative products and to have a competitive advantage. Although innovation, risk-taking and corporate venturing may have a delayed impact on a firm’s financial performance, managers should evaluate the implications and the success of CE activities in the long-term, not from a short-term perspective.

Building upon the existing literature, this is the first paper to investigate the effect of CE on a firm’s financial performance in Egypt during the Arab Spring. The manufacturing firms listed on the Egyptian Exchange were analyzed in a quasi-natural experiment, taking into account the moderating role of an environmental jolt, namely, the Arab Spring.

This paper seeks to summarise the results of available research on the use of high velocity oxy‐fuel (HVOF) thermal‐spray technique to provide protection against high temperature corrosion and erosion‐corrosion of materials.

This paper describes one of the recent thermal‐spray processes, namely HVOF thermal‐spray technology and presents a survey of the studies on the use of this technique to provide protection against corrosion and erosion‐corrosion of high temperature alloys, with a special emphasis on boiler steels.

High temperature corrosion and erosion‐corrosion are serious problems observed in steam‐powered electricity generation plants, gas turbines, internal combustion engines, fluidized bed combustors, industrial waste incinerators and recovery boilers in paper and pulp industries. These problems can be prevented by changing the material or altering the environment, or by separating the component surface from the environment. Corrosion prevention by the use of coatings for separating materials from the environment is gaining importance in surface engineering. Amongst various surface modifying techniques, thermal spraying has developed relatively rapidly due to the use of advanced coating formulations and improvements in coating application technology. One of the variants of thermal spraying, namely HVOF has gained popularity in recent times due to its flexibility for in‐situ applications and superior coating properties.

This review covers mainly information that has been reported previously in the open literature, international journals and some well‐known textbooks.

The paper presents a concise summary of information for scientists and academics, planning to start their research work in the area of surface engineering.

This paper fulfils an identified information/resources need and offers practical help to an individual starting out on a career in the area of surface engineering for erosion‐corrosion and wear.

This paper aims to evaluate the antimicrobial and antioxidant activity of ethanol, methanol and aqueous extracts of the jujube fruit.

The fruit samples were harvested from Ziziphus lotus L. in three regions of Morocco: Aïn Chifae (Immouzer), Saiss (Fez) and Guercif. The fruit extracts were obtained by Soxhlet method using ethanol, methanol and water, and then a phytochemical screening was done for each extract. Total phenolic and total flavonoids contents were also determined. Afterward, the antimicrobial activity of the studied extracts was evaluated using the broth microdilution method. To estimate the total antioxidant effect of these extracts, the DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging and phosphomolybdate tests were performed.

Results showed that the highest content of polyphenols and flavonoids was found for ethanol and methanol extracts, while the lowest content was found in the aqueous extracts for all populations studied. Thus, results showed that the highest content of phenolic compounds was recorded in the population of Fez. Methanol extract of this population was the richest in polyphenols (30.36 mg/g) and in flavonoids (13.03 mg/g). The antimicrobial tests showed that Enterococcus faecalis and Pseudomonas aeruginosa were the most sensitive (6.25 mg/ml), compared to the other tested strains. Based on the minimal bactericidal concentrations/minimal fungicidal concentration or MFC/MIC ratio, it seems that ethanol extracts showed a bactericidal effect against Escherichia coli, Staphylococcus aureus and Bacillus subtillis, and a bacteriostatic effect against Enterococcus faecalis. On the other hand, the methanol extract showed bacteriostatic effect against Enterococcus faecalis and Pseudomonas aeruginosa. In addition, methanol extracts of Ziziphus lotus have significant antioxidant potent.

Methanol and ethanol extracts of Ziziphus lotus fruit have demonstrated strong antimicrobial effect. Moreover, the authors were able to show that the extract of Ziziphus lotus fruit has a very important antioxidant power.

The purpose of this paper is to investigate the relationship between marketing mix (MM), information technology capabilities (ITCAP) and corporate entrepreneurship (CE). Additionally, the study has attempted to address the moderating influence of ITCAP on MM–CE relationship.

To achieve the objectives of the study, data was collected from managers working in the upper and middle departments in some major Algerian banks. To test the hypotheses of the study, simple regression and PROCESS macro with moderated multiple regression were used.

The results of the study revealed that the MM and ITCAP positively affect entrepreneurship, and the ITCAP of banks and their interaction with the MM contributed positively to promoting entrepreneurship for companies through the moderate influence of ITCAP on the relationship between the MM and CE.

It is very difficult to present the generalization of the results of this study because some of the major banks mainly drove the study sample. Therefore, researchers are encouraged to test the proposed propositions further.

The results of the study suggested that policymakers in the banking sector in Algeria seriously consider developing the MM for its direct role in the CE. Specifically, the moderate role of ITCAP indicated that an effective alignment of the bank’s ITCAP with elements of the MM could enhance the entrepreneurship position of the bank. Therefore, it is necessary to pay attention to the importance of these factors to foster entrepreneurship in the services sector.

The role of MM in CE has been overlooked in the extant literature, especially in the emerging economies. In addition, this study extends the body of knowledge through evaluating the moderating role of ITCAP using the effect of interaction in PROCESS macro with moderated multiple regression for path analysis.

Coronavirus disease 2019 (COVID-19) is an infectious disease that has rapidly spread to most cities in the world since December 2019 causing a rise in global mortality and adverse effects on mental health. This paper aims to examine the potential implications of the pandemic for mental health in societies with economic and political instability, focusing on Lebanon.

Previous empirical research into mental health and COVID-19 was examined in relation to the Lebanese context.

There is a risk of poor mental health in Lebanon owing to the deleterious effects of military conflict and political instability over several decades. More recently, the country is also experiencing the worst economic crisis in its history with unprecedented rates of unemployment, inflation, poverty, and devaluation of the national currency. It is suggested that the lockdown measures may be depriving the Lebanese people of effective coping strategies, such as group memberships (e.g., religion), social support and community involvement, during the COVID-19 outbreak. This in turn may lead to the deployment of maladaptive coping strategies in the population.

Mental health services are still in their formative phases in Lebanon and mostly run by civil society organizations. There is an urgent need for a national action plan to respond to the potential mental health burden and use of maladaptive coping strategies which may arise in the aftermath of COVID-19.

This paper provides a novel analysis of mental health in Lebanese society through the lens of social, political, economic and psychological factors.

A method for controlling the quality of finite element analyses for plate structures is proposed herein. It is based on the concept of error in the constitutive relation as well as on associated techniques for constructing admissible displacement‐stress fields with respect to a reference model. In this study, the chosen model is either Reissner‐Mindlin’s or Kirchhoff‐Love’s model. The finite element used is the DKT element; these error estimators allow us to determine that this element converges for Kirchhoff‐Love’s model. Once these error estimators have been identified, techniques of adaptive meshing developed in 2D are applied and several examples are presented.

This cross-sectional study focuses on the social psychological correlates of self-harm and suicidal ideation during the COVID-19 (coronavirus disease 2019) outbreak in Lebanon, which is a country characterized by political and economic instability.

A convenience sample of 191 Lebanese individuals completed measures of length of being in lockdown, fear of COVID-19, job insecurity, political trust, self-harm and suicidal ideation. Data were analyzed using independent samples t-tests and multiple regression.

Fear of COVID-19 was associated with neither self-harm nor suicidal ideation. Males and people with lower income reported higher suicidal ideation than females and those with higher income, respectively, and religiosity was inversely associated with suicidal ideation. People who reported self-harm generally exhibited lower political trust than those who did not report self-harm.

Beyond the fear of COVID-19, the socioeconomic sequelae of COVID-19 (especially the economic fallout and declining political trust), which are accentuated in already economically and politically unstable societies, may precipitate poor mental health and maladaptive coping strategies in Lebanon. There is a need to ensure adequate access to mental health services to the general population amid the COVID-19 outbreak in Lebanon.

This study provides novel insight into the risk factors for self-harm and suicidal ideation in Lebanon during the COVID-19 pandemic.

The benefits of interlibrary co‐operation are considered, especially in the context of developing countries. The history of library co‐operation schemes throughout the world is briefly described. The constraints on interlibrary co‐operation are also considered. A survey of academic and research libraries in the Ibadan area is reported and a possible initial co‐operation scheme outlined.