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The purpose of this paper is to investigate the rheological characteristics of graphene nanoplatelets (GNPs) and hybridized nanocomposite consisting of multi-walled carbon nanotubes (MWCNTs) and GNPs as an additive on lithium-based grease. The experiments of nanogrease are examined in different values of shear stress, apparent viscosity, temperature and shear rate using Brookfield Programmable Rheometer DV-III ULTRA and characterized by high-resolution transmission electron microscope (HRTEM) and X-ray diffraction (XRD).

First, GNPs was mixed well with lithium grease using mechanical stirring at 3,500 rpm for 15 min at room temperature to form a homogenous composite at different concentrations (0.5, 1, 1.5, 2 and 2.5 Wt.%). Afterwards, MWCNTs and GNPs are mixed and dispersed well in the lithium grease using a sonication path for 30 min and mechanical stirring at 3,500 rpm for 15 min at 28°C to form a homogenous nanocomposite.

The results indicated that 1 Wt.% of GNPs is the optimum concentration. Subsequently, the weight percentage of additives varying between MWCNTs and GNPs are tested, and the result indicate that the grease containing GNPs had a 75 per cent increase in shear stress and 93.7 per cent increase in apparent viscosity over ordinary grease.

This work describes the inexpensive and simple fabrication of nanogrease for improving properties of lubricants, which improve power efficiency and extend lifetimes of mechanical equipment.

This paper aims to improve the tribological properties of lithium complex greases using nanoparticles to investigate the tribological behavior of single additives (nano-TiO₂ or nano-CeO₂) and composite additives (nano-TiO₂–CeO₂) in lithium complex greases and to analyze the mechanism of their influence using a variety of characterization tools.

The morphology and microstructure of the nanoparticles were characterized by scanning electron microscopy and an X-ray diffractometer. The tribological properties of different nanoparticles, as well as compounded nanoparticles as greases, were evaluated. Average friction coefficients and wear diameters were analyzed. Scanning electron microscopy and three-dimensional topography were used to analyze the surface topography of worn steel balls. The elements present on the worn steel balls’ surface were analyzed using energy-dispersive spectroscopy and X-ray photoelectron spectroscopy.

The results showed that the coefficient of friction (COF) of grease with all three nanoparticles added was low. The grease-containing composite nanoparticles exhibited a lower COF and superior anti-wear properties. The sample displayed its optimal tribological performance when the ratio of TiO₂ to CeO₂ was 6:4, resulting in a 30.5% reduction in the COF and a 29.2% decrease in wear spot diameter compared to the original grease. Additionally, the roughness of the worn spot surface and the maximum depth of the wear mark were significantly reduced.

The main innovation of this study is the first mixing of nano-TiO₂ and nano-CeO₂ with different sizes and properties as compound lithium grease additives to significantly enhance the anti-wear and friction reduction properties of this grease. The results of friction experiments with a single additive are used as a basis to explore the synergistic lubrication mechanism of the compounded nanoparticles. This innovative approach provides a new reference and direction for future research and development of grease additives.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2023-0291/

This study aims to reduce the harm of industrial lubricants to consumers. Composite aluminum-based grease (CAG) was prepared, and medical-grade montmorillonite (M-MMT) was used to improve the antiwear performance of the prepared grease.

The influence of the additive (M-MMT) on the tribological performance is mainly investigated using a ball-disc wear tester, and the wear scar surface about the disc was characterized by white light interferometer and electrochemical workstation. Moreover, the cell viability test was used to evaluate the safety of the grease.

The results indicated that for the grease containing 1.5% M-MMT, the average coefficient of friction was reduced by about 46% compared with the CAG, the wear volume of the disc reduced by about 74%. Moreover, CAG and 1.5% M-MMT-containing CAG were proved safety by means of the cell viability test.

The integral properties of CAG can be improved with the medical-grade materials as the additives, while ensuring the safety.

The purpose of the paper is to showcase the significant achievements of Egypt's scientists in the 20th century across various fields of study such as medicine, physics, chemistry, biology, math, geology, astronomy and engineering. The paper highlights the struggles and successes of these scientists, as well as the cultural, social and political factors that influenced their lives and work. The aim is to inspire young people to pursue careers in science and make their own contributions to society by presenting these scientists as role models for hard work and dedication. Ultimately, the paper seeks to promote the importance of science and its impact on society.

The purpose of this review is to present the scientific biographies of Egypt's most distinguished scientists, primarily in the field of Natural Sciences, in a balanced and comprehensive manner. The work is objective, honest and abstract, avoiding any bias or exaggeration. The author provides a clear and concise methodology, including a brief introduction to the scientist and their field of study, an explanation of their major contributions, the impact of their work on society, any challenges or obstacles faced during their career and their lasting legacy. The aim is to showcase the important achievements of these scientists, their impact on their respective fields and to inspire future generations to pursue scientific careers.

The group of outstanding scientists in 20th century Egypt were shaped by various factors, including familial upbringing, education, society, political and cultural atmosphere and state support for scientific research. These scientists made significant contributions to various academic disciplines, including medicine, physics, chemistry, biology, mathematics and engineering. Their impact on their communities and cultures has received international acclaim, making them role models for future generations of scientists and researchers. The history of these scientists highlights the importance of educational investments and supporting scientific research to foster innovation and social progress. The encyclopedia serves as a useful tool for students, instructors and education professionals, preserving Egypt's scientific heritage and honouring the scientists' outstanding accomplishments.

The encyclopedia preserves Egypt's scientific heritage, which has been overlooked for political or other reasons. It is a useful tool for a variety of readers, including students, instructors and education professionals, and it offers insights into universally relevant scientific success factors as well as scientific research methodologies. The encyclopedia honours the outstanding scientific accomplishments of Egyptian researchers and their contributions to the world's scientific community.

The practical implications of this paper are several. First, it highlights the importance of education, family upbringing and societal support for scientific research in fostering innovation and social progress. Second, it underscores the need for continued funding and support for scientific research to maintain and build upon the accomplishments of past generations of scientists. Third, it encourages young people to pursue scientific careers and make their own contributions to society. Fourth, it preserves the scientific heritage of Egypt and honors the contributions of its outstanding scientists. Finally, it serves as a useful tool for students, instructors and education professionals seeking to understand the factors underlying scientific success and research methodologies.

The social implications of the paper include promoting national pride and cultural identity, raising awareness of the importance of education and scientific research in driving social progress, inspiring future generations of scientists and researchers, reducing socioeconomic disparities and emphasizing the role of society, politics and culture in shaping scientific researchers' personalities and interests.

The paper's originality/value lies in its comprehensive documentation of the scientific biographies of Egypt's most prominent scientists in the 20th century, providing unique insights into the factors that contributed to their development and their impact across various academic disciplines. It preserves Egypt's scientific heritage and inspires future generations of scientists and researchers through the promotion of educational investments and scientific research. The encyclopedia serves as a useful tool for education professionals seeking to understand scientific success factors and research methodologies, emphasizing the importance of supportive and inclusive environments for scientific development.

The study investigates perceptions and debate that are linked to the relationship between religion, alcohol, tourism and hospitality within the context of an Islamic tourist destination. An analytical approach involving a review of literature, assessment of conservationists’ attitude representing Islam and Christianity, and current trends using a student sample to determine intentions is used. The study findings suggest that alcohol and religiosity are not compatible, use, abuse and dependency are more common among non-believers than believers. A tense dispute continues in the Arab World around alcohol. The study contributes to the literature by highlighting economics, social practice, theoretical and managerial implications related to alcohol service in Egypt and suggests a way forward for global Muslim staff working in the hospitality, tourism, and travel industries.

The study uses an analytical approach involving a review of literature, assessment of conservationists’ attitude representing Islam and Christianity and current trends using a student sample to determine intentions.

The study findings suggest that alcohol and religiosity are not compatible, use, abuse and dependency are more common among non-believers than believers. A tense dispute continues in the Arab World around alcohol.

The study is assessing the relationship between religion, alcohol, hospitality and tourism within the context of Egypt, advances knowledge about halal tourism and hospitality by explicitly linking religious obligations and the implication on tourism. The findings should be used with caution considering the subjectivity of responses and the size of the sample.

The service/hospitality industry managers could be Muslims or non-Muslims representing major airlines, hotels and restaurants where alcohol is served by Muslim employees. These managers should consider avoiding the sale or serving of alcohol completely, and if not, they must not force their workers to serve alcohol if they chose not to.

Faith-based (e.g. Muslims, Seventh Day Adventists and Mormons), ideological or ethically driven alternative services should be created for the staff concerned with alcohol service/consumption. Employment is to be provided to adherents of these faiths or ideologies as an alternative resort.

This research aims to examine the macro determinants that significantly affect financial development in the Middle East and North Africa (MENA) region, which could be used furtherly to play a major role in economic sustainability since one of the major driving forces for economic development is the financial development.

The significant determinants of financial development should be efficiently used by the MENA region countries for creating huge financial sector development and innovation, stimulating economic development in turn and leading to the completion of the cycle of development and sustainability. To achieve this study's objective, the researcher employed a quantitative method to develop an econometric model.

This model consisted of two Panel EGLS Cross-Section Random Effects Models (REMs) in which Domestic credit to the private sector as a percentage of GDP (?PCGDP?_it) and stock market capitalization ratio (?SMC?_it) were taken as the dependent variables. In addition, the independent variables included the corruption perception index, financial freedom (FF), political stability (PS) and trade openness (TO). The researcher extracted the data for the analysis from different databases including the World Bank, the Organization for Economic Cooperation and Development and the International Monetary Fund. Throughout the first – Panel EGLS Cross-Section Random Effects Model, it turned out that, while FF, TO and corruption index had a positive relationship with ?PCGDP?_it, PS had an adverse effect on ?PCGDP?_it. The second – Panel EGLS Cross-Section Random Effects Model showed that, while PS and TO had a positive effect on stock market performance, the corruption index and FF had an adverse effect on stock market performance.

Throughout the first – Panel EGLS Cross-Section Random Effects Model, it turned out that, while FF, TO and corruption index had a positive relationship with ?PCGDP?_it, PS had an adverse effect on ?PCGDP?_it. The second – Panel EGLS Cross-Section Random Effects Model showed that, while PS and TO had a positive effect on stock market performance, the corruption index and FF had an adverse effect on stock market performance.

The purpose of this study is to propose a comprehensive strategic model to manage profitability. Strategic management accounting concepts and tools are adopted to explore and manage the main profitability drivers (cost, assets, and revenue).

A deductive approach is used to identify the variables of the profitability model. Phase one of this study rely on reviewing prior literature in the field in order to identify the key profitability drivers that uses in managing profitability (costs, assets and revenue).Phase two of the research focuses on testing the perceptions of the managers of Egyptian “Information and communications technology” sector, the relative merits of such a model.

The most important finding in the current study, which has not been investigated in previous studies, is that the proposed comprehensive profitability model which contains cost, the assets and revenue techniques was a better predictor of profitability than the alternative models, which contain a combination of two variables.

As the first study of its kind, this model contributes to the theoretical literature in the field. It is also a practical contribution in managing profitability of the Egyptian “Information and communications technology” sector.

To investigation the centrality of islamic work ethic (IWE) in the lives of managers in Kuwait and provide a useful insight into the nature of work environment and organizational culture.

The participants were 762 managers randomly selected from government and private sectors. Among participants 50 per cent were female; 73 per cent were Kuwaitis. Two measures were used: IWE and Loyalty scales. Correlation analysis and one‐way multivariate analysis along with frequency distribution were used to analyze the data.

The results indicated that managers scored high on IWE and loyalty scales. There was a positive high correlation between the two measures. Demographic and organizational variables had significant influence on managerial orientations. In particular, it was found that expatriates scored higher than Kuwaiti managers on both IWE and loyalty and men scored relatively higher than women on IWE.

Based on findings specific implications related to work environment, strengthening work involvement, and enhancing organizational loyalty were identified. Furthermore, the interplay of tradition and economic prosperity and their impact on IWE were briefly examined.

The paper highlights not only the importance of work ethics in a relatively rich country but also provides a useful insight into the linkage between IWE and loyalty and the changing nature of work in a country that has recently experienced profound social and economic changes.

This paper aims to examine why the alliance formed between non-Islamist forces and state actors to oust Mohamed Morsi from power in 2013 broke down quickly.

This paper makes use of original data set derived from three waves of surveys fielded in 2011, 2014 and 2015 that ask questions about public threat perception. Around 10 elite interviews were also conducted to further test the study’s hypothesis.

On the one hand, non-Islamists, civic forces challenged the status and interests of state actors in a way that made state actors view them with heightened distrust. On the other, many civic forces, in face of high threat perception, prioritized law during and order after Morsi’s removal, driven – at least partly – by shifts in public attitudes.

Many views look at transitions in the Arab world from the angle of how Islamists interact with traditional power holders. Such an approach, however, could be reductionist in many ways because it disregards civic forces. This is a point this paper seeks to address.

Money laundering weakens the role of the construction industry in stimulating economic growth. The purpose of this paper is to explore the connection between money laundering on the construction sites and undocumented foreign workers, based on a narrative drawn from a qualitative research.

Throughout the study, qualitative methods, i.e. interviews, site visits and document analysis, were used. However, the data for this paper was primarily derived from an interview. Thematic analysis was used to analyse the data.

The findings show that construction personnel who have access to the business’s financial affairs are the most likely to engage in illicit transactions. The size of the project as well as the multiple layers of organisations involved made it easy for launderers to operate. The appealing commission provided incentives to opportunistic personnel. In this regard, the wages for undocumented workers, which were primarily paid in cash, provided a considerable opportunity for the subcontracting organisations to engage in money laundering.

While the single narrative method with an omniscient narrator allows for the conceptualisation of a human experience with money laundering, the depth of information and interpretations is limited. Emerging qualitative research methods may be incorporated in the future to provide a more extensive information due to the fact that money laundering data is complex and sensitive that few people want to discuss.

The multidisciplinary approach of this research provides a pedagogical way that focuses primarily on the disciplines of construction management and business ethics to demonstrate real-world money laundering practice. Understanding such phenomenon on sites opens up key avenues for future research into developing an anti-money laundering regime for the construction industry.