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The purpose of this paper is to numerically study the phenomenon of separation and subsequent reattachment that happens due to a sudden contraction or expansion in flow geometry, in addition, to investigating the effect of nanoparticles suspended in water on heat transfer enhancement and fluid flow characteristics.

Turbulent forced convection flow over triple forward facing step (FFS) in a duct is numerically studied by using different types of nanofluids. Finite volume method is employed to carry out the numerical investigations. with nanoparticles volume fraction in the range of 1-4 per cent and nanoparticles diameter in the range 30-75 nm, suspended in water. Several parameters were studied, such as the geometrical specification (different step heights), boundary conditions (different Reynolds [Re] numbers), types of fluids (base fluid with different types of nanoparticles), nanoparticle concentration (different volume fractions) and nanoparticle size.

The numerical results indicate that the Nusselt number increases as the volume fraction increases, but it decreases as the diameter of the nanoparticles of nanofluids increases. The turbulent kinetic energy and its dissipation rate increase as Re number increases. The velocity magnitude increases as the density of nanofluids decreases. No significant effect of increasing the three steps heights on Nusselt along the heated wall, except in front of first step where increasing the first step height leads to an increase in the recirculation zone size adjacent to it.

The phenomenon of separation and subsequent reattachment happened due to a sudden contraction or expansion in flow geometry, such as forward facing and backward facing steps, respectively, can be recognized in many engineering applications where heat transfer enhancement is required. Some examples include cooling systems for electronic equipment, heat exchanger, diffusers and chemical process. Understanding the concept of these devices is very important from the engineering point of view.

Convective heat transfer can be enhanced passively by changing flow geometry, boundary conditions, the traditional fluids or by enhancing thermal conductivity of the fluid. Great attention has been paid to increase the thermal conductivity of base fluid by suspending nano-, micro- or larger-sized particles in fluid. The products from suspending these particles in the base fluid are called nanofluids. Many studies have been conducted to investigate the heat transfer and fluid flow characteristics over FFS. This study is the first where nanofluids are employed as working fluids for flow over triple FFS.

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.

This research aims to examine the role of green intellectual capital (GIC) dimensions in promoting sustainable healthcare as reflected by sustainable performance. The mediating effect of green absorptive capacity (GAC) and moderating role of environmental turbulence were also explored.

Structural equation modeling was utilized for hypotheses testing of a survey data set of 387 at healthcare organizations operating in Iraq. The data were collected using purposive sampling with expert judgment from senior managers and professionals.

Contrary to previous studies, the findings showed that only green human and relational capitals predict green performance and only green human capital predicted economic performance. GAC was related to green human capital, green structural capital and performance, and played a significant mediating role on the relationships.

Even though the research was limited to one region of a single country, Iraq, GAC can be modified by managers to enhance GIC for sustainable healthcare performance. This action must be viewed in terms of the future timing of the impact while managers display strong conviction for sustainability commitment. Managers will find GRC least associated with performance, but that GIC dimensions work best in unison.

The examination of GIC with GAC as moderated by environmental turbulence contributes nascent theoretical insights in sustainable healthcare.

The recent COVID-19 has obliged governments to enact large-scale policies to contain it. A topic of economic debate is the quantification of the impact that these policies can create in the economy, with the aim of activating regulatory mechanisms to minimize this impact. In this vein, this study aims to propose a quantification of the effects of the Italian government policy that blocks nonessential production activities.

The authors use a multisectoral extended inoperability model on the social accounting matrix of Italy. The analysis identifies the pandemic’s impact on outputs, endogenous demands, value-added and disposable incomes of institutional sectors.

The construction and real estate sectors revealed a significant contraction followed by the retail trade and hotel and catering services sectors. The output contraction further impacts the value-added generation, disposable income and final demand components.

The current pandemic is alleged to have a greater impact than the epidemics of the past century, considering the present dimension of the world economy and the increasing interconnections between industries and institutions. In this scenario, it is challenging to safeguard not only human health and life but also the economy. Hence, there is a need to establish a trade-off between health and economics; and in this regard, the current study empirically quantifies the impact of health measures on the economy. The findings of this study help identify the sectors that are more prone to disaster effects and also present the structure of income circular flow in the Italian economy.

Roots of global Terrorism are in ‘failed’ states carved out of multiracial empires after World Wars I and II in name of ‘national self‐determination’. Both sides in the Cold War competed to exploit the process of disintegration with armed and covert interventions. In effect, they were colluding at the expense of the ‘liberated’ peoples. The ‘Vietnam Trauma’ prevented effective action against the resulting terrorist buildup and blowback until 9/11. As those vultures come home to roost, the war broadens to en vision overdue but coercive reforms to the postwar system of nation states, first in the Middle East. Mirages of Vietnam blur the vision; can the sole Superpower finish the job before fiscal and/or imperial overstretch implode it?

The purpose of this paper is to investigate the effect of graphene platelets (GPLs) on the low-speed contact between a mass and surface of a multi-layer polymer beam.

This problem is primarily organized by first-order shear deformation beam theory and nonlinear Hertz rule. GPLs are distributed along the beam thickness direction. The Halpin–Tsai micromechanics model is applied for computing the effective Young’s modulus of the GPLs/polymer composites. In the formulation process, the principle of conservation of energy is first used and the histories of results are extracted using the separation of variables and Runge–Kutta method.

In comparing the responses with the available data, a good agreement is observed. The effects of the weight fraction and distribution pattern on the impact response of polymer beam reinforced with GPLs are studied. Results show that contact force is increased, contact time and beam recess are decreased with increasing of weight fraction of GPLs. Also, among the different distribution patterns, the contact force depended on value of GPLs at the point of contact.

The effects of GPLs addition on the multi-layer polymer beam has a novelty in impact problems.

This paper aims to discuss the evolution of the Egyptian banking sector and the main trends in financial development in Egypt. The purpose of this study is to examine empirically the relationship between the development of the financial sector and economic growth in Egypt between 1980 and 2016.

The paper draws comparisons based on critical financial indicators between Egypt and selected emerging markets and developing economies. It uses a new data set of financial development indexes released by the International Monetary Fund. This paper uses econometric time series modelling of bivariate regressions for real growth per capita and measures of financial development to assess the relationship between financial development and economic growth in Egypt.

There are three specific findings based on the empirical analysis. First, there is a strong association between real growth per capita and financial development measured by money supply to GDP. Second, access to and the efficiency of banking services are not associated with real per capita income. Third, the Financial Markets Access Index – which compiles data on market capitalization outside of the top ten largest companies and the number of corporate issuers of debt – indicates a robust association with real per capita GDP.

The paper uses advanced empirical investigation techniques and new data sets available to assess the critical relationship between finance and growth in Egypt. The main policy implications of the empirical results of this paper suggest a stronger focus on promoting a more proactive role for the financial services industry in Egypt. In particular, there is a critical role for bank financing to support the private sector to maintain an inclusive growth momentum. Further development of the capital market will promote sustainability of such economic growth.

The purpose of this paper is to establish practical guidelines for benchmarking eight total quality management (TQM) practices vital to pharmaceutical companies’ performance. The paper also proposes the use of an analytic total quality index (TQI) as a benchmarking tool and illustrates the importance and effectiveness of this benchmarking methodology by applying it in two comparative studies of three Jordanian pharmaceutical companies.

In order to achieve the above-mentioned purpose, the data were gathered through a questionnaire that was used to evaluate the gap between the ideal and current status of the quality management system and distributed to the quality units from three companies: pharmaceutical manufacturing company, a pharmaceutical manufacturing company working in the same field and a pharmaceutical service providing research services to a pharmaceutical manufacturing companies. And the mean differences between the current and ideal states for the eight critical TQM practices were compared for these two comparative studies using the t-test.

Each of the two comparisons reveals statistically significant differences regarding the perceptions of actual and ideal scores for manufacturing and service companies on five out of eight critical factors and, on two out of eight critical factors for manufacturing and manufacturing companies.

The pharmaceutical companies, regardless of whether they are manufacturing or service company, can adopt benchmarking techniques which were applied in this case study to improve their performance and their product/service quality.

The consequences of this research can support organization managers and policy makers in effectively benchmarking the identified TQM practices in their organizations using the proposed TQI benchmarking tool.

The purpose of this paper is to examine the direct and indirect moderation effects of demographic and socio-economic(s) factors on the adoption of Islamic banking in UAE.

Convenience sampling was done on the residents of Sharjah, Dubai, and Abu Dhabi. A closed-ended questionnaire with 30 items was designed and pre-tested before the start of the study. Path analysis and moderation testing were the main analytical approach. A total of 320 respondents completed the survey.

The research revealed that demographic and socio-economic(s) moderators may have direct and indirect moderation effects on the adoption of the Islamic banking in the UAE, which indicates the importance of these factors in the provision of Islamic banking products and services in the UAE.

This study further revealed that these moderators have huge practical implications for Islamic bank managers and marketers as they can exploit these demographics to enhance their market share in the UAE.

In UAE, minimal attention has been directed toward the role moderators would play in the criterion that individual investors would use in the adoption of Islamic banking products and services in a cosmopolitan environment that is experiencing competition from conventional banks.

An extensive review of the existing literature on the adoption of Islamic banking reveals that no empirical research has been undertaken to explore the role played by demographic and socio-economic(s) moderators in the adoption of Islamic banking in UAE and internationally. This study attempts to fill this gap.

The purpose of this paper is to investigate the coupled effect of magnetic field and radiation on convective heat transfer of low electrically conductive dielectric oxide melt.

The 3D Navier–Stokes equations are formulated using the vector potential-vorticity formulation and solved using the finite volume method (FVM). The radiative heat transfer equation is discretized using the FTnFVM method. A code was written using FORTRAN language.

The obtained numerical results are focused on the effect of the different parameters on the heat transfer and the flow structure with a special interest on the 3D transvers flow. It is found that the flow is developing in inner spirals and the magnetic field intensifies this 3D character. The radiation acts mainly at the core of the enclosure and causes the apparition of the merging phenomenon near the front and back walls.

The effect of magnetic field on convective heat transfer of highly electrically conductive fluids has been intensively studied. Reciprocally, the case of a fluid with low electrical conductivity is not so much investigated, especially when it is coupled with the effect of radiation. These two effects are studied in this paper for the case of a low-conductive LiNbO3 oxide melt.