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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 reliability of accounting internal control systems (AICS) is often viewed as a primary concern of auditors. Over the past three decades, several reliability models have been proposed for internal control. The main goal of these models is to provide an objective approach to evaluate the reliability of internal control systems. In addition, the models seek to assess the degree of audit reliance that can be placed on internal controls. This paper has a two‐fold objective: (1) to present an overview of the descriptive and prescriptive reliability models developed for the design and evaluation of internal control systems, and (2) to discuss the effects of various factors on the reliability assessment. Furthermore, two methods to estimate process reliabilities are presented and several numerical examples are provided to show the detailed calculations of the reliability and economic efficiency of accounting internal control systems.

Through addressing academics in four public business schools in Egypt, the authors of this paper aim to uncover how meaningful work might shape the mental health of the addressed academics post COVID-19.

The author employed a qualitative research method through semi-structured interviews with 44 academics from four business schools selected from among 25 public institutions of higher education in Egypt. The author subsequently used thematic analysis to determine the main ideas in the transcripts.

The authors’ findings show that business academics usually consider meaningful work as playing a major role in shaping their mental health, especially after a crisis. This indicates that the more they perceive their jobs as valuable and worthwhile, the more they can deal with limitations and mental health issues (e.g. anxiety, stress, inadequate sleep, etc.) that accompany crisis. The findings also show that during the time of the COVID-19 crisis, employees (business academics in this case) have not placed so much importance to their autonomy (ability to choose and/or participate in decision-making processes) in the workplace. Instead, they care more about their relatedness (sense of belongingness) and their level of competence (sense of capability). Accordingly, the authors show that having academics that develop a sense of purpose for their academic duties in a time of crisis has less mental health disorders. Subsequently, post crisis, business academics can feel a continuous sense of relatedness and find ongoing opportunities to work and learn.

This paper contributes by filling a gap in HR management, in which empirical studies on the relationship between mental health and meaningful work have been limited so far.

The adoption and usage of information and communication technology (ICT) has introduced transformation in the tourism arena with ICT applications extensively used in tourism industry. In addition to ICT, an advanced infrastructure is essential for the development of tourism industry. Thus, the goal of present research is to probe the impact of ICT and infrastructure on tourism development (TD) in 28 Asian economies using method of moments panel quantile regression (MM-QR) model introduced by Machado and Silva (2019) applied to a panel data from 2008 to 2020. Empirical findings demonstrate that there is an asymmetric non-linear effect of ICT and infrastructure through all quantile range. This indicates that ICT has negative effect on TD in poor countries while positive impact in rich countries. Negative impact in poor countries may be due to higher establishment cost and information technology (IT) productivity paradox. However, results confirm the importance of ICT and infrastructure in endorsing the development of tourism sector in Asian nations by lessening time and money costs and facilitating travelers.

Due to herbs and plants’ therapeutic properties and simplicity of availability in nature, humans have used them to treat a variety of maladies and diseases since ancient times. Later, as technology advanced, these plants and herbs gained significant relevance in some industries due to their suitable chemical composition, abundant availability and ease of access. Aegle marmelos is a species of plant that may be found in nature. Yet, little or very little literature was located on the coloration behavior of this plant’s leaves. This study aims to focus on the effect of different parameters on the extraction of colorant from Aegle marmelos leaves.

Some factors that affected on the extraction processes were examined and found to have significant impacts on the textile dyeing such as the initial dye concentration, extracted temperature, extracted bath pH and extracted time were all changed to see how they affected color extraction. The authors report a direct comparison between three heating methods, namely, microwave irradiation (MWI), ultrasonic waves (USW) and conventional heating (CH). The two kinetic models have been designed (pseudo-first and pseudo-second orders) in the context of these experiments to investigate the mechanism of the dyeing processes for fabrics under study. Also, the experimental data were analyzed according to the Langmuir and Freundlich isotherms.

From the result, it was discovered these characteristics were found to have a substantial effect on extraction efficiency. Temperature 90°C and 80°C when using CH and USW, respectively, while at 90% watt when using MWI, period 120 min when using CH as well as USW waves, while 40 min when using MWI, and pH 4, 5 and 10 for polyamide, wool and cotton, respectively, were the optimal extraction conditions. Also, the authors can say that wool gives a higher absorption than the other fabric. Additionally, MWI provided the best color strength (K/S) value, and homogeneity, at low temperatures reducing the energy and time consumed. The coloring follows the order: MWI > USW > CH. The adsorption isotherm of wool could be well fitted by Freundlich isotherm when applying CH and USW as a heating source, while it is well fitted by the Langmuir equation in the case of MWI. In the study, it was observed that the pseudo-first-order kinetic model fits better the experimental results of CH with a constant rate K₁ = −0.000171417 mg/g.min, while the pseudo-second-order kinetic model fits better the experimental results of absorption of both MWI (K2 = 38.14022572 mg/g.min) and USW (K₂ = 12.45343554 mg/g.min).

There is no research limitation for this work. Dye was extracted from Aegle marmelos leaves by applying three different heating sources (MWI, ultrasonic waves [USWW] and CH).

This work has practical applications for the textile industry. It is concluded that using Aegle marmelose leaves can be a possible alternative to extract dye from natural resource by applying new technology to save energy and time and can make the process greener.

Socially, it has a good impact on the ecosystem and global community because the extracted dye does not contain any carcinogenic materials.

The work is original and contains value-added products for the textile industry and other confederate fields.

Cotton fabrics can be dyed with reactive and/or direct dyes in aqueous baths under certain specific conditions of pH, salt, temperature, time, etc., and rendered fire retardant through reaction with reactive phosphonopropionamide compounds. In the presence of reactive tertiary amines and reactive phosphorous derivatives, cotton fabrics can be dyed with reactive, direct or acid dyes in the absence of the usual added alkalis and salts, and in the mean time, the fabric becomes fire retardant with wash and wear properties. To verify such claims, reactive aminating agents are synthesized by reacting different amine compounds that have various numbers of amino groups with acryl amide and formaldehyde. The pad-dry-cure technique is applied to treated fabrics with aqueous finishing formulations that contain dyestuff and reactive amine-compounds; the cotton fabric will simultaneously impart reactive dyeing, easy-care inishing and fire-retardant properties. Systematic studies show that in the presence of 6% weight/weight, reactive amine in an aqueous formulation yields cotton fabric with the least loss in tensile strength and elongation at break, and an enhancement to the crease recovery angle. By adding the dyestuff to the aqueous formulation at fixed nitrogen content for treated cotton (0.2%) under identical dyeing conditions, the colour strength (K/S) increases for dyed cotton. The fastness properties of the dyed fabric are improved or remain unaltered for the three types of dyestuffs used

With the disaggregation and fine-slicing of global value chains, offshoring and outsourcing has become increasingly relevant for many MNEs. The purpose of this chapter is to understand the value creation of the receiving partner of outsourcing activities. This is a firm that will have many outsourcing alliances with partners, and one perspective to frame these alliances is the alliance portfolio perspective. We ask – how can a firm on the receiving end of outsourcing create value through the management of its alliance portfolio?

Through a case study of a company supplying products to manufacturing industries, we investigate ways in which the company adds value for customers through different models of customer integration. Applying an alliance portfolio perspective, we study benefits of grouping alliances with customers and suppliers.

Whereas most studies of alliance portfolios have focused on value creation within a portfolio, we find that the mediating capability of coordinating between groups or portfolios of alliances is critical. We also see that the risk aspect is important for firms receiving outsourcing activities.

Our findings have implications for the strategy and organization of the mediating firm on the receiving end of outsourcing. We have only data from one firm, and therefore our findings need to be tested further.

Our findings have implications for managers organizing large alliance portfolios to include risk and mediation capabilities.

The chapter uses original in-depth data.

Reactive amine-amide derivatives are prepared via the addition reaction of different primary and secondary amines on acrylamide (AAm) using equivalent molar ratios and the resultant product is methylolated using equivalent amounts of HCHO. Bis (hydroxymethyl carbamoylethyl) ethylamine (I), tetra (hydroxymethyl carbamoyl ethyl) ethylene diamine (II) and penta (hydroxymethyl carbamoylethyl) diethylenetriamine (III) are prepared by reaction between ethylamine or ethylenediamine or diethylenetriamine and AAm. N-Hydroxydiethyl-phosphonopropianamide (IV) is prepared via Mecheal addition reaction of diethylphosphite with AAm followed by reaction with HCHO. To impact flame-retardancy and easy care finishing to cotton fabric aqueous formulations of compound IV, etherified methylolated melamine (EMM) and/or compounds III, II or I have been prepared. Cotton fabric treated by pad–dry–cure system, the drying time was investigated. Cured cotton fabrics are fire retardant if the aqueous formulation contains 12 % w/w of compound IV and 6 % w/w of EMM respectively. Physical and mechanical properties are less deteriorated when compound III, II or I are used instead of EMM and the liberated HCHO is almost decreased to one half by replacing EMM by one of the prepared methylol compounds. Treatments with compounds III, II or I is impart antibacterial and antifungus properties to the finished fabric.

This paper aims to examine the association between green innovation and the cost of equity in China. This study relies on the investors’ base perspective and shareholders’ perceived risk perspective to investigate the relation between green innovation and the cost of equity in China.

The paper uses firm-fixed effect regression for a sample of Chinese public companies for the period 2008–2018.

The authors find a negative relationship between green innovation and the cost of equity capital. This negative association is found to be more pronounced for less financially constrained firms, during periods of high economic policy uncertainty, and for firms with a strong internal control environment. Finally, the paper shows that the negative association became more pronounced after the passage of the Environmental Protection Law of China in 2012. The results remain robust to possible endogeneity concerns.

This study contributes to the green innovation literature by documenting that shareholders favorably view firms implementing green innovation policies. The study also has policy implications for Chinese regulators in improving the green credit policy.

Within the last few years, a couple of presentation systems have been developed for assisting higher education. This article aims to provides an overview of available systems and highlight differences regarding their individual intention and technical approaches.

The article consists of a comprehensive system and literature review and provides a taxonomy. Famous systems are categorized and discussed including their individual approaches.

The advantages and disadvantages of different approaches are presented. The discussion provides readers also with information relevant for rating systems according their personal needs.

The categorization for presentation systems can be extended and applied for the categorization of audience response systems.

A source of information that assists users while they choose an appropriate existing presentation system and developers while they design new ones.

This article presents a workflow‐oriented taxonomy for educational presentation systems which is used to analyze several systems. In addition, the different underlying conceptual and technical approaches of different systems are discussed in this work. The provided information is useful for users and developers of such systems.