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This paper aims to synthesize 6-ethyl-4-hydroxyquinolin-2(1H)-one as a new enol-type coupling component in the preparation of some 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes and evaluate the solvent effects on their absorption in ultraviolet-visible spectra.

6-Ethyl-4-hydroxyquinolin-2(1H)-one was synthesized by thermal cyclocondensation reaction of N, N′-bis(4-ethylphenyl) malonamide at 130–140°C in polyphosphoric acid. This compound was then applied in the azo-coupling reaction with some aniline-based diazonium salts, so as to prepare seven new mono-heterocyclic azo dyes. The structures of the compounds were confirmed using mass spectroscopic technique. Fourier transform infra red (FT-IR) and 1H proton nuclear magnetic resonance (1H NMR) and carbon-13 nuclear magnetic resonance (13 C NMR) studies on the structure of the azo compounds revealed that they exist as two E- and Z-isomers of hydrazone tautomer both in solid and solution state. The effects of acid and base on the visible absorption spectra of the dyes were also evaluated and discussed.

Ultra violet-visible UV-vis absorption spectra of the dyes didn’t show significant variation by changing of solvents because of intramolecular H-bonding between proposed hydrazone forms and 2- and 4-keto functions in their structures. The spectra of the dyes were not sensitive to the addition of acid but were very sensitive to base.

The synthesized 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes are new members in the 4-hydroxyquinolin-2(1H)-one azo dyes family, where very few details regarding the synthesis of such dyes are reported before in the literature. They are unique in terms of synthesis and spectral properties.

This study aimed to (1) analyze whether the perceived organizational support (POS) was a significant predictor of performance and stress and (2) explore the mediating role of engagement in these relations.

To test the hypotheses, the authors collected data with 200 working adults in a mandatory quarantine due to COVID-19 pandemic crisis.

The results showed that the POS contributed to increase engagement, and consequently, job performance. These relations also proved to be significant for stress, because when the POS increased, the work engagement also increased, and as a result decreased occupational stress.

This study relied on a cross-sectional design. Therefore, future research should consider a daily design to replicate this study and analyze daily fluctuations. Overall, the authors can conclude that work engagement is an affective process through which POS decreases stress and increases performance.

This study tests the mediating effect of work engagement on the link between POS, stress and performance, and its theoretical and practical implications of these findings are discussed.

This paper aims to prepare new modified alkyd resins and use it as an antimicrobial binder for surface coating applications.

Various modified alkyd resins were prepared by partial replacement of 3,6-dichloro benzo[b]thiophene-2-carbonyl bis-(2-hydroxy ethyl)-amide as a source of polyol with glycerol and confirmed by acid value, FT-IR, 1H-NMR. The modified alkyd resins were covering a wide range of oil lengths and hydroxyl content (0%, 10%, 20% and 30% excess-OH). The antimicrobial activity of the prepared alkyds was also investigated. The coatings of 60 ± 5 µm thickness were applied to the surface of glass panels and mild steel strips by means of a brush. Physico-mechanical tests, chemical resistance and antimicrobial activities were investigated.

The obtained results illustrate that the introduction of benzo[b]thiophene derivative as a modifier polyol within the resin structure improved the film performance and enhanced the physico-mechanical characteristics, chemical resistance and the antimicrobial activities.

The modified alkyd resins can be employed as antimicrobial binders in paint compositions for a variety of surfaces, particularly those that are susceptible to a high number of bacteria.

Modified alkyd resins based on antimicrobial heterocyclic compounds have the potential to be promising in the manufacturing of antimicrobial coatings and development of paints, allowing them to function to prevent the spread of microbial infection, which is exactly what the world requires at this time. Also, they can be applied in different substrates for industrial applications.

This paper aims to synthesize new screen-printing ink formula based on new derivatives of azo thiadiazol disperse dyes and evaluate their characteristics after being printed on polyester fabric substrates.

New dispersed dyes based on 1, 3, 4-Thiadiazole derivatives (dyes 1 and 2) were prepared and confirmed by different analyses, infrared (IR), mass and nuclear magnetic resonance (NMR) spectroscopy, and then formulated as colored materials in the screen-printing ink formulations. Printing pastes containing the prepared dyestuffs and other ingredients were used for printing polyester using screen-printing or traditional printing. The characteristics of printed polyester fabric substrates were measured by color measurements such as a*, b*, L*, C*, E, Ho, R% and color strength, as well as light, washing, crock and alkali perspiration fastness, and finally, the depth of penetration was evaluated.

The prepared 1, 3, 4-Thiadiazole derivatives (dyes 1 and 2) were obtained from the reaction of 5,5’-(1,4-phenylene)bis(1,3,4-Thiadiazole-2-amine) with resorcinol and m-toluidine as a coupling component. The suitability of the prepared dyestuffs for silk screen-printing on polyester fabrics has been investigated. The prints obtained from a formulation containing dye 1 possess high color strength as well as good overall fastness properties if compared to those obtained using dye 2.

The method of synthesis of the new dyestuffs and screen-printing ink provides a simple and practical solution to prepare some new heterocyclic disperse azo dyes, and they are formulated in the screen-printing inks for printing on a polyester fabric substrate.

The prepared disperse dyes based on 1,3,4-Thiadiazole derivatives (dyes 1 and 2) could be used in textile printing of polyester on an industrial scale.

Claims are increasingly becoming a norm in construction projects and thus an area that is attracting interventions through researches. This paper aims to establish causes–effects relationship of claims in construction projects.

This is correlation study type of study that attempts to establish causes–effects relationship of claims in construction projects. Significant causes and effects of construction claims were determined using one-sample t-test. To establish the relationship, the significant causes and effects of construction claims were correlated using bivariate correlation analysis.

Among the significant causes, variations, change of scope of the project and delay in completion of works have high level of significant positive relationship with five to six other causes and positive relationship with multiple effects ranging from five to six. Besides, among significant effects, delay in completion and delivering of construction projects, poor contractual relationship among parties and extension of time have significant positive relationship with multiple causes.

The findings of this study are limited to causes-causes relationship and causes–effects relationship of claims in construction projects. This means effects–effects relationship was not covered that could be an important area to investigate as some of causes and effects are at times termed interchangeably.

With reference to previous studies which have focused on determining the causes and effects of construction claims, the findings of the current study have specific contribution on claims management as it divulges the causes of constructions claims that have multiplier effects to the project as a result of their linkage.

The paper unveils causes of claims with multiplier effects to construction projects for project participants to devise strategies to minimize and consequently eliminate them.

The purpose of this paper is as follows: First, understanding the nature of the relationship between corporate adoption of the concept of societal responsibility [availability of environmental awareness, clear vision of the impact of societal responsibility on financial performance, managers informing employees of the latest developments in societal responsibility programs, managers' response to their corporate social responsibility (CSR) proposals] in the form of an annual report that supports the success of the company's objectives, the company's management encourages employees to participate collectively in societal responsibility programs and to protect the environment from pollution in the petrochemical industry. Second, understand the nature of the relationship between the dimensions of corporate social responsibility concept (cultural, social, economic, ethical and legal) and protect the environment from pollution in the petrochemical industry. Third, the research also seeks to show the role of societal responsibility and its application in the petrochemical companies to protect the environment from pollution in The Governorate of Alexandria – Egypt, and come out with results and recommendations that could help protect the environment from the forms of environmental pollution resulting from the production processes of this industry.

The researcher has relied on each of the following approaches: Case study methodology is a research strategy aimed at solving a problem or facing a particular situation. It is based on preliminary hypotheses through full analysis of all data collected and recorded. Which depends on the study of a limited number of cases or vocabulary in-depth comprehensive study through the study of all or a large number of variables overlapping and interrelated and influential on the problem under consideration. Thus, it provides a deep and rich understanding of what is going on around the research and the processes that are related to it, and not only the external or apparent description of the situation or phenomenon; it cares about the total description and looks at the particles, in relation to the whole. Quantitative approach: by giving a numerical description indicating the size or size of the phenomenon or the degree of association with the phenomenon. Other phenomena. Accordingly, the role of the petrochemical companies in Alexandria Governorate, and the social responsibility programs carried out within the governorate in terms of importance, growth and requirements, and the most important characteristics and constraints and components and methods of work and developments have been described. Thus, the researcher can analyze the relationship between CSR and environmental protection from pollution in Alexandria Governorate.

There is paucity in the studies that dealt with the relationship between CSR and environmental protection against pollution in public organizations. There is agreement among the sample on the importance and feasibility of adopting the concept of social responsibility and placing it at the top of the top management concerns, especially in the field of petrochemical companies. With the need to take concrete implementation measures to support social responsibility programs aimed at serving the community among all stakeholders. The effective implementation of the mechanisms for the implementation of meaningful social responsibility programs requires fundamental changes in management practices, existing organizational structures and the quality of personnel working in the relevant departments, in general, and the social responsibility group, in particular, which may be difficult for political and economic reasons.

Time: The study period was set from 2015 to 2017. Place: The study focuses on the petrochemical companies operating in Alexandria. Humanity: The study focuses on the employees of the petrochemical companies operating in Alexandria Governorate.

The adoption of social responsibility positively affects the protection of the environment from pollution, and this effect shows that the adoption of the concept of corporate social responsibility is influenced by the following factors: increasing the participation of workers with healthy environmental contributions to the productive process; increasing the companies' economic and social activities toward protecting the environment from pollution; increasing the capacity of companies to pay greater costs to preserve the environment; increasing the awareness of green consumers with the products it offers Companies; development of continuous internal work environment companies; and clearly defined strategy followed in social responsibility programs.

The social responsibility of the public organizations derives their strength through, first, the keenness of these organizations to analyze the variables of the ethical dimension of social responsibility and their availability, which will lead the organizations to provide their services with the highest quality and sincerity. That this analysis (ethics of individuals) as training members of the social responsibility team to solve problems using brainstorming and provide employees with official data related to improving work (ethics of leadership), such as the identification of business objectives through the participation of managers with subordinates, and the punishment of workers who exhibit immoral behaviors (ethics of productive processes) as a decision-making process to ethical standards regardless of the costs involved. When there is an immoral behavior and managers are responsible for implementing the changes needed to reach the targeted outcomes), second, promote partnerships with other relevant sectors for community service.

According to the results of the previous studies and the applied study results, the researcher would like to submit a mechanism to the directors and heads of the boards of directors of the Egyptian petrochemical companies under study.

Ant Colony Optimization and Particle Swarm Optimization represent two widely used Swarm Intelligence (SI) optimization techniques. Information processing using Multiple-Valued Logic (MVL) is carried out using more than two discrete logic levels. In this paper, we compare two the SI-based algorithms in synthesizing MVL functions. A benchmark consisting of 50,000 randomly generated 2-variable 4-valued functions is used for assessing the performance of the algorithms using the benchmark. Simulation results show that the PSO outperforms the ACO technique in terms of the average number of product terms (PTs) needed. We also compare the results obtained using both ACO-MVL and PSO-MVL with those obtained using Espresso-MV logic minimizer. It is shown that on average, both of the SI-based techniques produced better results compared to those produced by Espresso-MV. We show that the SI-based techniques outperform the conventional direct-cover (DC) techniques in terms of the average number of product terms required.

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.

The Internet of things (IoT), an emerging research field, offers solutions to several problems and may result in a paradigm shift in various areas, including education. However, this approach has been under-utilised. Therefore, this research investigates and highlights the primary factors that influence the impact of the IoT on education and reveals the current state of academic research to manage higher education (HE) resources effectively and efficiently.

Data from 35 academic papers were collected and analysed to understand the current situation and assess the readiness of HE to adopt IoT. A literature review is a well-established method for developing knowledge and interpreting issues under consideration. This study systematically analysed the various research methodologies used to adopt IoT, summarising the content of the studies and highlighting the main factors that may affect IoT adoption in HE.

The authors examined 95 papers; 35 were investigated and analysed. The literature review and analysis of academic papers revealed the factors influencing the adoption of IoT technology in HE.

By examining the evidence, this study contributes to understanding the context and supplements existing research. It conducts a systematic literature review to assess the impact of the IoT on the educational process, proposes future research directions and presents findings that aid the efficient management of HE resources.