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This study aims to investigate the effect of trisodium nitrilotriacetic acid (NTA) on the physical and luminescence emission properties of NaLuF4:Yb, Tm Upconversion (UC) particles and compared with trisodium citrate (CA). Upconversion materials have been remarkably considered in many applications in the past decades. However, the morphology of the UC particles affects their emission properties, depending on the synthesis situation.

The UC particles were synthesized by the hydrothermal method. Properties such as crystal phase, particle morphology, particle size, smoothness and uniformity of particle surface and their emission intensity in the UV–Vis region were studied.

Observations showed that pH is an essential factor in determining the crystalline phase. In addition, quality factors affect the morphology, particle size and surface smoothness of crystalline facets. It was also found that the UC particles synthesized in the presence of trisodium NTA have a much higher emission intensity than those synthesized in the presence of CA. The use of UC particles in security inks to maintain the brand was also investigated.

To the best of the authors’ knowledge, for the first time, the effect of trisodium NTA as a chelating agent was investigated on morphology and UC intensity of NaLuF4:Yb,Tm phosphor.

The purpose of this work was to perform a systematic study on the effect of formulation on the physical and mechanical properties of ultaviolet (UV) curable urethane acrylate resins. In addition, the authors wanted to derive mathematical formula for the prediction of physical and mechanical properties for the aforementioned system.

The experiments were carried out based on mixture experimental design to determine the effect of different multifunctional acrylates (i.e. 1,6-hexanediol diacrylate (HDDA), tripropylene glycol diacrylate (TPGDA), trimethyolpropane triactylate (TMPTA)) concentration on the physical and mechanical properties of a UV curable polyurethane acrylate system. The urethane oligomer was synthesized and characterized by the research team. Microhardness, adhesion strength and scratch resistance of the cured films were evaluated as the physical and mechanical properties.

The results revealed that the resin and TMPTA concentrations had the most significant effects on the microhardness property. Adhesion strength of the films showed a linear trend with respect to all variables. Moreover, all components also had a significant and complex influence on the scratch resistance of the cured systems. In addition, mathematical equations proposed by mixture experimental design were derived for all the mentioned properties.

Other multifunctional acrylate monomers (i.e. more than three functional) can be used in the formulations. The kinetics of the curing can affect on the network formation and consequently on the properties of the cured films.

The obtained results can be used by the researchers who are active in the field of structure-property relationship of polymers and surface coatings. The reported data and the mathematical equations can also be used for the formulating of an appropriate formulation based on a specific application.

A systematic and statistical-based approach, i.e. mixture experimental design, was used to evaluate the effect of formulation on some of the properties of a UV curable polyurethane acrylate system. A urethane oligomer and three different multifunctional acrylate monomers as reactive diluents were used in the formulations. Noteworthy to mention that several mathematical models were derived by using analysis of variance for the prediction of the properties studied in this system.

The purpose of this work was to study the effect of chemical structure of reactive diluents on the curing behaviour and physical–mechanical properties of a titanium dioxide pigmented UV-curable epoxy acrylate system.

Two different tri-functional and two different tetra-functional acrylate monomers were used as reactive diluents in the formulations. The curing behaviour of the formulations was studied by using photo-differential scanning calorimetry analysis. The rate of curing, conversion at the maximum rate and ultimate conversion for different formulations were calculated. In addition, the physical and mechanical characteristics of the cured films, including glass transition temperature and modulus, were measured by using a dynamic mechanical analysis technique.

The results showed that the ultimate conversion for non-pigmented pentaerythritol triacrylate (PETA) and trimethylol propane triacrylate (TMPTA) formulations were almost similar, but the interference effect of titanium dioxide particles on the curing of the PETA formulations was found to be more considerable in comparison to the TMPTA formulations. The extent of reaction for tetra-functional acrylate monomers was considerably less than those for tri-functional acrylate monomers. The Tg and storage modulus of non-pigmented PETA, TMPTA and pentaerythritol tetraacrylate (PE4TA) formulations were almost the same and higher than that for ditrimethylol propane tetraacrylate (DiTMP4TA) formulations. However, Tg and storage modulus of pigmented tetra-functional acrylate monomer formulations were higher than those for tri-acrylate monomer formulations.

The curing conditions (temperature and UV intensity) can affect the network formation and consequently will affect on the properties of the cured films.

The pigmented UV-curable coatings are interested for many industries such as wood and automotive industries. The reported data can be used by the formulators working in the R&D departments. In addition, the results obtained can be used by the researchers who are active in the field of structure–property relationship for UV-curable coatings.

UV-curing systems are considered as one of the most environment-friendly coatings system. Therefore, the developing of its knowledge can help to extend its usage to different applications.

The photopolymerisation of pigmented coatings is a great challenge and is hardly investigated in the literature. Therefore, in this research, the effect of chemical structure and functionality of different multifunctional acrylate monomers on the curing behaviour of pigmented formulations was investigated.

The chapter presents emerging evidence on the development of the platform economy, paying particular attention to the motivations for entering platform work, the conditions of platform work, and the extent of social protections afforded platform workers. Debate thus far has tended to be highly speculative and lacking in grounded empirical analysis, with policy-makers in particular actively looking to regulate platform work on the basis of its novelty as a form of employment within the wider context of the decline of the “standard employment relationship.” The chapter explores such concerns through an analysis of European Union labor market data and a unique data-set of circa 1,200 online “click workers” across four established platforms. A novel contribution of the analysis is to differentiate between those that only work on platforms (work-dependent platform workers) and those that do such work in addition to another job. The analysis suggests that work-dependent platform workers are more likely to be differentiated by their motivations for doing such work than their experiences of job quality or access to social protections. However, the relationship between platform working and levels of social protection is complex, notably in terms of combined level of social protection and the contractual arrangement of additional job holders. This leaves us to conclude that policy initiatives designed to address gaps in social protections for platform workers would be more appropriately targeted toward problems of insecure work more broadly. Finally, a number of areas for future research are outlined.

The purpose of this study is to analyze the transportation of heat and mass in three-dimensional (3D) shear rate-dependent viscous fluid. Thermal enhancement plays a significant role in industrial and engineering applications. For this, the authors dispersed trihybrid nanoparticles into the fluid to enhance the working fluid’s thermal enhancement.

The finite element method is a numerical scheme and is powerful in achieving convergent and grid-independent solutions compared with other numerical techniques. This method was initially assigned to structural problems. However, it is equally successful for computational fluid dynamics problems.

Wall shear stress has shown an increasing behavior as the intensity of the magnetic field is increased. Simulations have predicted that Ohmic heat in the case of trihybrid nanofluid (MoS₂–Al₂O₃–Cu/C₂H₆O₂) has the greatest value in comparison with mono and hybrid nanofluids. The most significant influence of chemical reaction on the concentration in tri-nanofluid is noted. This observation is pointed out for both types of chemical reaction (destructive or generative) parameters.

Through a literature survey, the authors analyzed that no one has yet to work on a 3D magnetohydrodynamics Carreau–Yasuda trihybrid nanofluid over a stretched sheet for improving heat and mass transfer over hybrid nanofluids. Herein, molybdenum disulfide (MoS₂), aluminum oxide (Al₂O₃) and copper (Cu) nanoparticles are mixed in ethylene glycol (C₂H₆O₂) to study the thermal enhancement and mass transport of their corresponding resultant mono (Cu/C₂H₆O₂), hybrid (Al₂O₃–Cu/C₂H₆O₂) and trihybrid (MoS₂–Al₂O₃–Cu/C₂H₆O₂) nanofluids.

Offshore outsourcing of non‐core business process has rapidly evolved as a ubiquitous organisational phenomenon. However, failure to follow a clear, systematic and effective outsourcing strategy to evaluate threats, uncertainties and numerous imponderables can cause global enterprise businesses major setbacks. The reasons for such setback could be largely due to lack of core competency, careful legal planning and due diligence to operating models associated with an outsourcing initiative. This paper attempts to collate and exemplify the distinct qualifying processes accommodating contractual and intellectual property rights and provide a worthwhile debate on intricate legal considerations when structuring multi‐jurisdictional outsourcing deals.

The paper presents a comparative analysis of strategic legal and management framework by weighing the risks and evaluating the threats which would assist the decision making process of firms when selecting an appropriate offshore partner to carry out their IT‐development work.

Importance of legal intervention and due diligence to service agreements is further elevated as, at every phase of an outsourcing arrangement, compliance issues and contractual obligations can affect the success of an enterprise customer and its relationship with their outsourcing service provider.

The authors suggest that an exhaustive qualitative and quantitative industry specific research analysis be conducted in order to better define the principles and standards governing sub‐contracting arrangements.

A broader exposure to the strategic management and regulatory framework might provide firms with vantage points from which they could assess and identify new opportunities, evaluate threats and adopt effective risk mitigation strategies. Compliance to security standards and safeguard of information acquisition, analysis and usage should emerge as the mainstream strategy for outsourcing.

The paper offers insights and an overview of management and legal issues in the context of offshore technology outsourcing.

For better mapping the path of intellectual capital (IC) research, the purpose of this paper is to selectively review empirical studies of IC published, and identify theories, components and three dimensions of analysis: national IC (NIC), regional IC (RIC) and organizational IC (OIC).

The systematic literature review (SLR) subject to analysis is based on empirical studies made between 1960 and 2016, and focuses on three dimensions of analysis: NIC, RIC and OIC. Four research questions were designed, using the following databases, namely, Web of Science, Scopus and Google Scholar, for data collection purposes.

The SLR unveils a multidimensional taxonomy for measuring and classifying the type of IC applicable to the different levels of analysis and provides some recommendations for future studies of NIC, RIC and OIC, by outlining the need for clear definitions of components and measures of IC and identifying strengths, limitations and future research avenues.

In order to fill the gap found in the literature and the non-existence of a study clarifying the multiple dimensions of analysis of IC, this SLR makes a twofold, original contribution to the literature on management: providing an SLR of the main empirical studies dealing with different units of analysis; and identifying a multidimensional taxonomy for measuring and classifying the type of IC applicable to the different levels of analysis.