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Long time ago, multistructured materials showed great interest being considered as the bridge between bulk and atomic materials. Core-shell particles are kind of composite materials that refer to multilayered structures with a core totally surrounded by shell(s) (onion-like structure). These new structures can offer an advantage of applying new adjustable parameters like shape, stoichiometry and chemical ordering, in addition to the opportunity of tailoring more complexed structures for different applications. Recently it was found that these structures can be tuned and taken for more advanced path with novel structures formed of core surrounded by multishells. The purpose of this study is to study the effect of the new anticorrosive pigments with its mutual shells and how each shell affects the performance of the pigment in protecting the metal and which shell will be more relevant in its effect.

The prepared pigments were characterized using X-ray fluorescence, X-ray diffraction, TEM and SEM/EDX to prove their core-shell structure, and then they were integrated in coating formulations to evaluate their anticorrosive activity using immersion test and electrochemical impedance spectroscopy (EIS).

The results showed that the prepared core-shell pigments possess a lot of unique characteristics and can offer improved anticorrosive performance in the generated coatings.

Core-mutual shells structured pigments were prepared for improving the corrosion resistivity of the organic coatings as a new trend in anticorrosive pigments.

This paper aims to identify the mechanism through which consumer empowerment, created via the Facebook brand page (FBBP), is transformed into brand page stickiness. Specifically, a model examining the mediating role of FBBP experience and the moderating role of brand love is proposed and tested.

Data from 283 FBBP users were analyzed using structural equation modeling with partial least squares.

The findings reveal the positive effect of consumer empowerment and brand page experience on brand page stickiness. The mediating role of brand page experience and the moderating role of brand love were prominent in the consumer empowerment–brand page stickiness link.

This paper is novel in inaugurating the association between consumer empowerment and FBBP stickiness, which is mediated by brand experience and moderated with brand love. This paper enriches the understanding of how brand page stickiness can be enhanced in the social media context.

This paper guides managers to best utilize FBBP to create a pleasant experience and yield stickiness.

The purpose of this study is to investigate the authors' previously prepared and fully characterized poly (methacrylamide)-chitosan nanoparticles (CNPs) graft copolymer having 50.2% graft yield with respect to flocculation efficiency for ferric laurate aqueous dispersions. This was done to compare the ability of the latter cheap, biodegradable and ecofriendly hybrid natural-synthetic polymeric substrate as a flocculant in comparison with higher cost, nonbiodegradable and harmful polyacrylamide as a well-known synthetic flocculant counterpart.

The graft copolymerization process was carried out at 450°Cfor 120 min using (1.0 g) CNPs, methacrylamide (1.5 g), 100 mmol/l potassium chromate and 80 mmol/l mandelic acid. Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis and specific viscosity were used to characterize and analyze the resultant copolymer. The flocculation efficiency was conferred in terms of transmittance % and weight removal %. The main factors influencing the flocculation process, such as flocculent dose, flocculation medium pH, stirring speed, flocculation temperature and grafting extent, were comprehensively discussed.

The flocculation efficiency of the prepared copolymers revealed the following findings: increased by increasing the flocculant dose, pH, temperature and stirring speed to a maximum values denoted at 30 ppm, 6.0, 30°C and 50 r/min, respectively, then decreased thereafter; increased by increasing the extent of grafting within the range studied; showed a comparable flocculation efficiency in comparison with polyacrylamide as a synthetic polymeric flocculent; and, finally, a preliminary bridging mechanism representing the attraction between the anionic suspended particles ferric laurate and cationic poly (MAam)-CNPs graft copolymer has been projected.

The advancement addressed here is undertaken with using the authors’ poly (MAam)-CNPs graft copolymers having different extent of grafting (a point which is not cited in the literature especially for the authors’ prepared copolymer) as a hybrid natural-synthetic polymeric substrate as a flocculant for ferric laurate aqueous dispersions in comparison with the high cost and nondegradable polyacrylamide synthetic flocculant.

This study aims to address a comprehensive and integrated investigations pertaining to the preparation of AgNPs with well-defined nano-sized scale using the aforementioned poly (meth acrylic acid [MAA])–chitosan graft copolymer, which is cheap, nontoxic, biodegradable and biocompatible agent as a substitute for the traditionally used toxic reducing agents.

AgNPs are prepared under a range of conditions, containing silver nitrate and poly (MAA)–chitosan graft copolymer concentrations, time, temperature and pH of the preparation medium. To classify AgNPs obtained under the various conditions, ultraviolet–visible spectroscopy spectra and transmission electron microscopy images are used for characterization of AgNPs instrumentally in addition to the visual color change throughout the work. The work was further extended to study the application of the so prepared AgNPs on cotton fabric to see their suitability as antibacterial agent as well as their durability after certain washing cycles.

According to the current investigation, the optimal conditions for AgNPs formation of nearly 3–15 nm in size are 5 g/l, poly (MAA)–chitosan graft copolymer and 300 ppm AgNO₃ in addition to carrying out the reaction at 60°C for 30 min at pH 12. Besides, the application of the so prepared AgNPs on cotton fabric displayed a substantial reduction in antibacterial efficiency against gram-positive and gram-negative bacteria estimated even after 10 washing cycles in comparison with untreated one.

To the best of the authors’ information, no comprehensive study of the synthesis of AgNPs using poly (MAA)–chitosan graft copolymer with a graft yield of 48% has been identified in the literature.

The pursuit of manufacturing new inks with low financial cost is an urgent economic demand. Thus, the purpose of this paper is to synthesize some new pigments derived from Lithol Rubine (LR) via a successful simple route and to investigate their physicochemical properties for usage in the inks industry.

Two novel pigments were generated during the reaction of LR with Mn(II) and Co(II) salts in ethanolic solutions. The obtained pigments were isolated as solid compounds and characterized through elemental analysis, UV–vis, Fourier transform infrared, 1H NMR spectra, oil absorption, specific gravity, melting point, molar conductivity and magnetic moment measurements. Their dyeing and durability characteristics were examined using American Standard Testing Methods. The synthesized pigments were then applied in inks formulation.

The printing inks containing the two new pigments (LR–Mn and LR–Co) were compared to (GF 59-606 and GF 59-616), respectively. The results of this study showed that the performance of newly prepared pigments was comparable to that of commercial pigments currently in use in the inks industry.

LR and its new derivative pigments can be used in other different applications such as paper coating, crayon, rubber and paint industries.

The authors designed an efficient synthesis for some novel pigments. The synthesis technique is featured by a short reaction time, high yields and ease of use. The pigments developed would be good and cost-effective substitute for the original commercially available and expensive pigments used in the inks industry.

This study aims to focus on the main materials used in consolidation processes of illuminated paper manuscripts and leather binding.

For each material, chemical structure, chemical composition, molecular formula, solubility, advantages, disadvantages and its role in treatment process are presented.

This study concluded that carboxy methyl cellulose, hydroxy propyl cellulose, methyl cellulose, cellulose acetate, nanocrystalline cellulose, funori, sturgeon glue, poly vinyl alcohol, chitosan, chitosan nanoparticles (NPs), gelatin, aquazol, paraloid B72 and hydroxyapatite NPs were the most common and important materials used for the consolidation of illuminated paper manuscripts. For the leather bindings, hydroxy propyl cellulose, polyethylene glycol, oligomeric melamine-formaldehyde resin, acrylic wax SC6000, pliantex, paraloid B67 and B72, silicone oil and collagen NPs are the most consolidants used.

Illuminated paper manuscripts with leather binding are considered one of the most important objects in libraries, museums and storehouses. The uncontrolled conditions and other deterioration factors inside the libraries and storehouses lead to degradation of these artifacts. The brittleness, fragility and weakness are considered the most common deterioration aspects of illuminated paper manuscripts and leather binding. Therefore, the consolidation process became vital and important to solve this problem. This study presents the main materials used for consolidation process of illuminated paper manuscripts and leather bindings.

This study delves into the dynamics between Agile Response to Change (AR), Adaptive Scoping (AS), Stakeholder Engagement (SE) and Project Performance (PP), with a special focus on the moderating influence of Project Complexity (PC). The research, grounded in a thorough literature review, identifies critical gaps in these areas and examines the extent to which PC moderates the effects of AR, AS and SE on PP, offering new perspectives for managing complex projects.

The research develops a conceptual model based on a critical analysis of existing literature. A comprehensive questionnaire was designed, incorporating 28 items to measure AR, AS, SE, PP and PC. Data was collected from 136 project managers across various industries, and the responses were analysed using structural equation modelling (SEM) to explore the complex interplay between these variables.

The analysis revealed that internal AR (ARint) significantly enhances both quantitative (PPqt) and qualitative aspects of PP (PPql). AS and SE were found to positively influence PPql, but their impact on PPqt was not significant. Interestingly, PC was observed to negatively moderate the relationship between ARint and PPql, while its moderating effect on the relationship between ARint and PPql was not significant. The study also notes that PC does not significantly alter the positive correlations between AS, SE and PPql.

This research contributes to the existing body of knowledge by elucidating the relationships between ARint, AS, SE and different dimensions of PP. It uniquely explores the role of PC as a moderating variable in these relationships, offering valuable insights for practitioners and researchers in the field of complex project management.

This paper aims to investigate the relationship between global economic fluctuations and human development through four transmission channels (foreign direct investment (FDI), official development aid (ODA), remittances and export earnings) in Egypt as an open developing economy, in the period 1990–2015.

The paper uses a vector autoregressive model, which implies examining the impulse response functions and variance decompositions.

The results indicate that human development is negatively affected by global economic fluctuations through the four channels, namely, ODA, FDI, export earnings and remittances. In addition, the most effective transmission channels are FDI in the short run and export earnings in the long run.

While a large body of literature addresses the direct impact of business cycles and economic shocks on human development, only some studies focus on the indirect impact. The contribution is to identify the indirect impact of global economic fluctuations on human development in a developing economy, considering four transmission channels and to determine the most important of these channels. Moreover, using the human development index is an addition in this paper as most previous literature depends on other human development indicators such as children’s health, employment and schooling.

This study focused on exploring the performance factors (PFs) that impact Infrastructure Sanitation Projects (ISSPs) in the construction sector. The aim was twofold: firstly, to identify these crucial PFs and secondly, to develop a robust performance model capable of effectively measuring and assessing the intricate interdependencies and correlations within ISSPs. By achieving these objectives, the study aimed to provide valuable insights into and tools for enhancing the efficiency and effectiveness of sanitation projects in the construction industry.

To achieve the study's aim, the methodology for identifying the PFs for ISSPs involved several steps: extensive literature review, interviews with Egyptian industry experts, a questionnaire survey targeting industry practitioners and an analysis using the Relative Importance Index (RII), Pareto principle and analytic network process (ANP). The RII ranked factor importance,  and Pareto identified the top 20% for ANP, which determined connections and interdependencies among these factors.

The literature review identified 36 PFs, and an additional 13 were uncovered during interviews. The highest-ranked PF is PF5, while PF19 is the lowest-ranked. Pareto principle selected 11 PFs, representing the top 20% of factors. The ANP model produced an application for measuring ISSP effectiveness, validated through two case studies. Application results were 92.25% and 91.48%, compared to actual results of 95.77% and 97.37%, indicating its effectiveness and accuracy, respectively.

This study addresses a significant knowledge gap by identifying the critical PFs that influence ISSPs within the construction industry. Subsequently, it constructs a novel performance model, resulting in the development of a practical computer application aimed at measuring and evaluating the performance of these projects.

Smart contracts are self-executing computer programmes that have the potential to be used in several applications instead of traditional written contracts. With the recent rise of smart systems (e.g. Internet of things) and digital platforms (e.g. blockchain), smart contracts are gaining high interest in both business and academia. In this work, a framework for smart contracts was proposed with using reputation as the system currency, and conducts currency mining through fulfilling the physical commitments that are agreed upon.

A game theory model is developed to represent the proposed system, and then a system dynamics simulator is used to check the response of the blockchain with different sizes.

The numerical results showed that the proposed system could identify the takeover attacks and protect the blockchain from being controlled by an outsider. Another important finding is that careful setting of the maximum currency amount can improve the scalability of the blockchain and prevent the currency inflation.

This work is proposed as a conceptual framework for supply chain 4.0. Future work will be dedicated to implement and experiment the proposed framework for other characteristics that may be encountered in the context of supply chain 4.0, such as different suppliers' tiers, different customer typologies and smart logistics applications, which may reveal other challenges and provide additional interesting insights.

By using the proposed framework, smart contracts and blockchains can be implemented to handle many issues in the context of operations and supply chain 4.0, especially in times of turbulence such as the COVID-19 global pandemic crisis.

This work emphasizes that smart contracts are not too smart to be applied in the context of supply chain 4.0. The proposed framework of smart contracts is expected to serve supply chain 4.0 by automating the knowledge work and enabling scenario planning through the game theory model. It will also improve online transparency and order processing in real-time through secured multitier connectivity. This can be applied in global supply chain functions backed with digitization, notably during the time of the pandemic, in which e-commerce and online shopping have changed the rules of the game.