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The purpose of this paper is to evaluate the influence of nanoparticles as an additive on the tribological properties of calcium grease.

The nano additives in this research are with different concentration of multi carbon nanotubes (MWCNTs) and Talc powder (1, 2, 3, 3 and 5 per cent). The ratio of MWCNTs to Talc powder is 1:1. The tribological properties of hyper MWCNTs/Talc powder to calcium grease were evaluated using a pin-on-disk wear testing. The results show that the nano additives MWCNTs/Talc to calcium grease exhibit good performance in anti-wear and friction reduction. The action mechanism was estimated through analysis of the worm surface with x-ray diffraction and transmission electron microscope.

The result indicates that boundary film mainly composed of MWCNT and Talc powder, and other organic compound was formed on the worm surface during the friction test. In addition, the wear rate and coefficient of friction of nanogreases have shown excellent improvement about 80.62 and 63.44 per cent, respectively, at 4 Wt.% of MWCNTs/Talc powder. Moreover, the thermal conductivity of nanogrease increased about 51.72 per cent.

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

This work describes the fabrication of composite nanogrease based on carbon nanotubes (CNTs) as an additive at different volume concentrations 0, 0.5, 1, 2 and 3 Wt.% and investigates the correlation between CNTs and grease rheological behaviour. In addition, study the influence of shear thinning rate at various temperatures and investigates the thermal conductivity of nanogrease. The results demonstrated that grease behaves like a Newtonian viscoelastic material with a narrow linear domain. The thermal conductivity of nanogrease was enhanced by about 31.58 per cent, and the thermal and mechanical stabilities improved. Moreover, the apparent viscosity and dropping point increased by about 93 and 27 per cent, respectively.

Grease was dissolved in chloroform (10 Wt.%), at 25°C for 1 h. In parallel, functionalized CNTs with different volume concentrations (0.5, 1, 2 and 3 Wt.%) were dispersed in N,N-dimethylformamide; the dispersion was stirred for 15 min, and then sonicated (40 kHz, 150 W) for 30 min. Grease solution was then added to the CNTs. The nanofluid was magnetically stirred for 15 min and then sonicated for 2 h. This ensured uniform dispersion of nanoparticles in the base fluid.

Inexpensive and simple fabrication of nanogrease. Thermal conductivity of nanogrease was typically enhanced compared to other reported studies. Apparent viscosity and dropping point increases with the increase the volume concentration.

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.

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.

To enhance the tribological properties of nanogrease, one of the new technologies was used to synthesize a nanogrease having carbon nanotubes (CNTs) nanoparticles (NPs) with different concentrations. The microstructures of the synthesized NPs were characterized and evaluated by x-ray diffraction spectroscopy (XRD) and transmission electron microscopy (TEM). Tribological properties of the nanogrease were evaluated using a four-ball tester. The worn surface of four steel balls was investigated by scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDX).

Grease was dissolved in chloroform (10 Wt.%), at 25 °C for 1 h. In parallel, functionalized CNTs with different volume concentrations (0.5, 1, 2 and 3 Wt.%) were dispersed in N, N-dimethylformamide. The mixture was stirred for 15 min and then sonicated (40 kHz, 150 W) for 30 min. After that, the mixture was added to the grease solution and magnetically stirred for 15 min and then sonicated for 2 h.

The results suggested that CNTs can enhance the antiwear and friction properties of nanogrease at 0.5 Wt.% CNTs to about 57 and 48 per cent, respectively. In addition, the weld load of the base oil containing 0.5 Wt.% CNTs was improved by 17 per cent compared with base grease.

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

Although social anxiety disorder (SAD) is a common mental disorder, it is often under diagnosed and under treated. The aim of this study is to assess the prevalence, severity, disability, and quality of life towards SAD among students of Jazan University, Saudi Arabia. A cross-sectional study was conducted among a stratified sample of 500 undergraduate students to identify the prevalence of SAD, its correlates, related disability, and its impact on the quality life. All participants completed the Social Phobia Inventory, Leibowitz Social Anxiety Scale, Sheehan Disability Scale, and the WHO Quality of Life – BREF questionnaire. Of 476 students, 25.8% were screened positive for SAD. About 47.2% of the students had mild symptoms, 42.3% had moderate to marked symptoms, and 10.5% had severe to very severe symptoms of SAD. Students who resulted positive for SAD reported significant disabilities in work, social, and family areas, and this has adversely affected their quality of life as compared to those who screened negative for SAD. Students reported several clinical manifestations that affected their functioning and social life. Acting, performing or giving a talk in front of an audience was the most commonly feared situation. Blushing in front of people was the most commonly avoided situation. Since the present study showed a marked prevalence of SAD among students, increased disability, and impaired quality of life, rigorous efforts are needed for early recognition and treatment of SAD.

The choice between different financing sources is governed by a number of finance theories, particularly, trade-off theory and pecking order theory. However, the special characteristics of Islamic finance, which forces the exclusion of conventional bonds, leave Islamic banks with limited number of alternatives. Tier 1 sukuk are distinguished type of sukuk that combines the features of conventional bonds and stocks. This paper aims to answer the following question: Does the issuance of Tier 1 sukuk positively affect Islamic banks’ profitability or is their impact concentrated on enhancing Islamic banks’ capital adequacy ratios?

The data set used in this study consists of all United Arab Emirates (UAE) Islamic banks that issued Tier 1 sukuk over the period 2010–2020. Pooled and fixed effects panel regressions of Tier 1 sukuk and other control variables on three proxies of Islamic banks’ profitability were run. The selection of fixed-effect model is based on Hausman test, redundant fixed effects and likelihood ratio test.

This study reveals novel findings. Tier 1 sukuk increases both earnings per share (EPS) and capital adequacy ratios. That is, this study finds that there is a positive significant impact of Tier 1 sukuk on EPS, which indicates that issuing more Tier 1 sukuk will generate more return to shareholders in terms of higher EPS because of the lower cost of Tier 1 sukuk compared to equity. However, this study finds that there is an insignificant impact of Tier on sukuk on both return on assets and return on equity. Hence, it is concluded that Tier 1 sukuk does not increase the risk appetite of UAE Islamic banks.

Tier 1 sukuk is a niche instrument that has been recently used by Islamic banks. Hence, there are a limited number of Islamic banks that have issued this type of sukuk and consequently limited number of observations. Therefore, with the increased use of this instrument, a larger set of data will be available for examination. In addition, future research could examine the relationship between issuing Tier 1 sukuk and profitability in other countries where such sukuk have loss absorption feature. The impact of other types of sukuk, such as liability sukuk, on Islamic banks’ profitability could also be an interesting field of study.

This study recommends Islamic banks to issue more Tier 1 sukuk to enhance their profitability indicators while meeting Basel III accord. This study also recommends investors to purchase the stocks of Islamic banks that issue Tier 1 sukuk because they are able to offer them higher EPS. The authors advise the UAE regulators to allow Islamic banks to issue Tier 1 sukuk with loss absorption feature to enable Islamic banks engage in more risky activities that usually provide larger profits. This study also suggests that the Islamic Financial Services Board (IFSB) reclassifies Tier 1 sukuk, with loss absorption feature, within the highest quality of capital, common equity Tier 1, to encourage Islamic banks to issue this type of sukuk, especially Basel III accord and IFSB 15 require higher ratios of common equity Tier 1 to risk-weighted assets.

This research contributes to the existing literature in two ways. First, it adds to the existing literature on the impact of sukuk on Islamic banks profitability. That is, contrary to prior studies that merely investigate the impact of issuing ordinary sukuk on profitability, this study explores a distinguished type of sukuk, that is Tier 1 sukuk, that has been surprisingly ignored so far. Second, this study shows that it is not only capital adequacy ratios that have improved as a result of issuing Tier 1 sukuk but also Tier 1 sukuk reduce the cost of capital of UAE Islamic banks which has been reflected in a higher profitability proxied by EPS. Hence, these sukuk serve a dual function for Islamic banks by improving both capital adequacy and profitability ratios.

Graduates are expected to possess the knowledge and right skillset, commonly known as graduate attributes, which they need to become employable and work-ready. This study describes the approaches that were employed by an academic institution in developing an assessment framework for measuring the student achievement of the graduate attributes and learning outcomes.

It used thematic analysis in analyzing the 43 audit reports of higher educational institutions (HEIs) in Oman which have undergone the regional quality audit as well as the outcomes of the institutional standards assessment.

The analysis exposed the critical issues necessary for embedding graduate attributes and learning outcomes in higher education. Likewise, the study revealed that the assessment of the graduate attributes (GAs) and learning outcomes (LOs) is the area that garnered the most number of comments from the audit panel, and 69 per cent of the HEIs are still problematic in this area. Moreover, most of the HEIs in Oman lack the mechanisms to assess student learning as evidenced in the regional accreditation outcomes. Only 43.8 per cent of the HEIs, which have undergone the institutional accreditation process, have garnered a Met Rating in the Graduate Attributes and Student Learning Outcome criterion. Hence, this study presupposes its high relevance and usefulness to the work in this area, drawing from the experience of an HEI in Oman.

This study will present the relevant and meaningful content, especially good practices and potential gaps that inform HEIs regarding the current trends, policies, and practices relevant to the assessment of graduate attributes and learning outcomes in higher education.

This study extends the limited literature on the assessment of graduate attributes and learning outcomes, especially among the HEIs in Oman.

COVID-19 pandemic was a health crisis that plunged the world into economic turmoil due to its resultant national lockdowns across economies which brought business and market activities to a standstill. In order to adapt to ensuing restrictions owing to the pandemic, forge ahead in a new way of living, work and interactions with one another (new normal), digitizing business and market operations is considered a necessary option. Sukuk is an essential Islamic capital market product whose operations involve multiple parties/intermediaries alongside some technical financial, administrative and legal/shariah processes. On this note, this chapter aims to study and examine the need for digitizing and automating sukuk operations and related activities to pave way for innovation, development and better continuity of sukuk market. In conducting the study, a review of literature approach is employed where relevant works on sukuk and fintech were examined. Using content analysis, the chapter explored digitization of sukuk in the Islamic capital market via fintech and blockchain and associated benefits, including peculiar challenges therein. An interview was also conducted to better understand the Wethaq case study. The chapter reveals that digitizing sukuk issuance adds value to sukuk and remedies certain inadequacies associated with sukuk transactions; can increase transparency of underlying sukuk assets and cash flows and can reduce costs due to lesser number of intermediaries. Digitization is the future of sukuk issuance and will promote sukuk well through the COVID-19 crisis and beyond.