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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.

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.

The dielectric constant (E′), dielectric loss (E″) and power factor (tan §) were measured for various excess hydroxyl content resins (polyesteramide, alkyd/polyesteramide and alkyd resins) and also for their corresponding dry films. Measurements were conducted within the frequency band 105 to 107 Hz and temperature range 20–50°C. The various parameters affecting the dielectric behaviour of resin varnishes and their dry films are discussed. Also the effect of ageing at 110°C upon the dielectric behaviour of dry films is another parameter taken into consideration.

The shift in consumer focus towards green marketing mix elements is not a unique thing. Especially in recent times, most organizations are trying to implement green marketing strategies in order to influence customers as well as to reduce the negative impacts of environmental footprints. However, in recent times service marketing requires thorough implementation of a Green Marketing Mix as evidenced by Asian countries. However, research also claims that the use of a traditional green marketing mix is not a guarantee of success in the long run and therefore has been criticized by several researchers and scholars. Hence, there is a need to follow the Green-SIVA (Solution, Information, Access, and Value) concept in order to create a long-lasting impact on consumer buying and to discuss the application of tools in a more comprehensive manner. Although the linkage of Green-SIVA marketing might provide a new way to develop an effective marketing mix strategy for services. Hence, this chapter has been written purposely to discuss GMM elements with reference to the service industry of Pakistan and tries to develop an association with green-SIVA marketing practices in order to optimize service marketing practices.

This paper aims to explore social responsibility reporting of full-fledged Islamic banks in two developing countries, namely, Indonesia and Malaysia. Corporate social responsibility (CSR) has become an important aspect of business society. As such, companies have shown a growing interest in reporting their social and environmental initiatives.

Content analysis of the annual reports for three full-fledged local Islamic banks in Indonesia and three Islamic banks in Malaysia was carried out for the period of 2007-2011.

Results of the study revealed that CSR disclosure of Islamic banks has generally grown both in Malaysia and Indonesia. More specifically, it was found that workplace and community dimensions were the most highly disclosed areas by the Islamic banks in both countries.

The current study provides a cross-cultural perspective on social responsibility disclosure in Islamic banks across two countries. The study is limited by investigating a five-year time frame.

By discussing the findings according to the stages of growth model for CSR, the authors suggest that Islamic banks can enhance their responsiveness, and transform their role from being CSR reporters of social responsibility to responders.

While the tenets of CSR have a lot in common with Islamic moral law (Shariah), little is known about CSR disclosure of Islamic banks.

This paper aims to examine whether the audit committee moderates the relationship between audit quality and market reactions.

Using fixed effects and the GMM model for robustness, the study used 472 publicly listed firms on South Africa’s Johannesburg stock exchange spanning a period of six years from 2014 to 2019.

Results obtained show that audit quality impacts market reactions through share price and adjusted market returns. And, that the audit committee moderates the relationship between audit quality and market reactions in South Africa’s publicly listed firms. An effective audit committee is expected to play a crucial role in overseeing the audit process, ensuring the independence of auditors and promoting transparency and accountability which in turn impacts asset prices.

The study implies that governments and regulatory bodies in other developing economies could strengthen regulations about companies’ Acts, how firms regulate themselves and more so audit committees. Firms can also strive to make sure that audit committees are staffed with experts to promote higher audit quality and investor attention to get access to the much-alluded capital.

To the best of the authors’ knowledge, the study adds value by being the first to explore the subject matter of the importance of audit committees in defining audit quality and market reactions in publicly listed firms. The research adds to the body of knowledge on corporate governance and audit quality. It provides a case study specific to the South African context, contributing to the global literature on these topics.

A standalone microgrid (MG) is able to use local renewable resources and reduce the loss in long distance transmission. But the single-phase device in a standalone MG can cause the voltage unbalance condition and additional power loss that reduces the cycle life of battery. This paper proposes an energy management strategy for the battery/supercapacitor (SC) hybrid energy storage system (HESS) to improve the transient performance of bus voltage under unbalanced load condition in a standalone AC microgrid (MG).

The SC has high power density and much more cycling times than battery and thus to be controlled to absorb the transient and unbalanced active power as well as the reactive power under unbalanced condition. Under the proposed energy management design, the battery only needs to generate balanced power to balance the steady state power demand. The energy management strategy for battery/SC HESS in a standalone AC MG is validated in simulation study using PSCAD/EMTDC.

The results show that the energy management strategy of HESS maintains the bus voltage and eliminates the unbalance condition under single-phase load. In addition, with the SC to absorb the reactive power and unbalanced active power, the unnecessary power loss in battery is reduced with shown less accumulate depth of discharge and higher average efficiency.

With this technology, the service life of the HESS can be extended and the total cost can be reduced.

This paper aims to investigate the relationship between the Kingdom of Saudi Arabia (KSA)’s expenses in the health and social fields and the achievement of sustainable development goals (SDGs) 1 (elimination of poverty) and 3 (good health and well-being). This paper also examines the effects of the COVID-19 pandemic on these expenses and goals.

This paper observes the public expenses and the targets of the SDGs of KSA during 1981–2022. This paper tests the stationarity of the variables and then uses the ordinary least square model or the autoregressive distributed lag model, depending on the unit root test results. This paper also observes the change in target goals between the two years of the pandemic and the two preceding years.

The results show the influence of social expenditure on the progress of SDG-1, whereas the impact of health expenditure on SDG-3 is not significant. This paper also proves the impact of the pandemic on public expenses and social SDGs.

This paper attracts the attention of policymakers to the importance of assessing their SDG initiatives and the consequent outcomes. Additionally, this paper documents the initiatives for sustainable development in KSA, an important emerging country. Given the universal nature of the SDGs and the importance of KSA as an economic power with a large youth human capital potential, the findings offer insights applicable beyond KSA and provide valuable lessons for governments worldwide regarding the optimization of public spending for SDG achievement. Moreover, monitoring SDG advancement in this important country helps assess the progress of the the United Nations (UN)’s 2030 Agenda for Sustainable Development. Therefore, This paper helps boost the completion of this agenda and contributes to the bottom-up approach of the UN 2030 Vision, implicating all categories of stakeholders, including the academic community.

This paper furthers the literature on SDG achievement by analyzing the relationship between public expenses and SDGs. This paper contributes to the debate concerning the best methodology suitable for SDG valuation and adds to the few studies using autoregressive tests. Moreover, this paper enriches the scarce studies dealing with emerging countries and reviews the assessment of SDGs in KSA. Additionally, this paper investigates the effect of the COVID-19 pandemic on the assigned resources for SDGs and, consequently, on the related indicator scores.

This chapter examines the influence of external public borrowing resources on economic progress in Tunisia. The study focuses on two stages: First, the influence is studied in a direct sense and then in an indirect sense, i.e., through a transmission channel of this influence. By applying the autoregressive distributed technique with staggered lags (ARDL), over a period ranging from 1986 to 2019, the results showed that the influence of external borrowing resources on growth seems to be unfavorable in the short term but positive in the long term, hence the importance of the empirical technique chosen. Second, three interaction variables were tested, namely total government expenditure, government investment expenditure, and the real effective exchange rate. The results obtained call for better attention to the channels identified to maximize the positive influence of external public debt on the country's economic progress.