Search results

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 examine the optimal sourcing strategies and pricing decisions of competing toy manufacturers and to discuss how manufacturers’ decisions are impacted by competition.

The authors consider a single-period model to characterise the competition between two competing toy manufacturers. Both of them are free to choose between virgin material and recycled material. The authors consider two types of consumers: sensitive consumers who are concerned about product safety and prefer the toy made of virgin material and insensitive consumers who do not care what material is used in the toy. The competing manufacturers play a Cournot competition.

The results reveal a special case of a win-win situation for both the manufacturer and the consumer. In addition, an increasing number of sensitive consumers does not always raise the price of virgin-material toys.

The authors derive the manufacturer’s equilibrium sourcing strategies, corresponding market-clearing prices and profits obtained.

The paper investigates how toy manufacturers’ optimal sourcing strategies are impacted by competition, considering market segments.

Waste generated from electrical and electronic equipment, collectively known as E-waste, remains a persistent environmental, economic and social problem. Sustainable E-waste management (EWM) has numerous benefits, such as preventing electronic waste from entering landfills, reducing the need for virgin materials by recovering valuable materials from recycling and lowering greenhouse gas emissions. Circular economy (CE) practices are considered the initial steps toward sustainable EWM, but some hurdles have been reported in the adoption of these practices. Therefore, the current study aims to identify the common CE practices, sustainability of the EWM process and the challenges in EWM, and to develop a conceptual framework for effective EWM.

Very few studies have proposed frameworks that acknowledge the challenges and CE practices of EWM. To fill this gap, a systematic literature review (SLR) was performed, and 169 research articles were explored.

A total of seven challenges in the adoption of effective EWM were identified: rules and policy, infrastructure, consumer behaviour, informal sectors, community culture, technology and economy. Eight common CE practices were also found for effective EWM: reuse, recycle, remanufacturing, refurbishment, repair, reduce, recover and repurpose.

A conceptual framework guiding sustainable EWM was proposed, which includes solutions for the identified challenges, and CE practices with sustainable benefits.

Utilizing a self-regulatory perspective, the authors examine how narcissism influences perceived negative inequity and the downstream effects on self-enhancement motivation and organizational citizenship behaviors (OCBs) over time.

A total of 689 useable three-wave panel data were obtained via Amazon Mechanical Turk during a three-month period. A latent growth curve modeling approach using EQS 6.4 for Windows was employed to test the hypothesized model.

Results illustrate that individuals with higher levels of narcissism perceive higher levels of perceived negative inequity and then form higher levels of self-enhancement motivation, which prompt more OCB directed toward the organization (OCBO) than OCB directed toward individuals (OCBI). When perceived negative inequity increases over time, narcissists experience a faster increase in self-enhancement motivation, which also leads to a faster increase in OCBO compared to the increase in OCBI.

Theoretically, this study provides theoretical and empirical insights into understanding the process through which narcissists' OCBs are motivated. Practically, this study offers several practical recommendations that help managers manage OCBs effectively in the organization.

The aim of this study was to investigate the activity of 4-((4-((2-hydroxyethyl)(methyl)amino)benzylidene) amino)-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one (HEMAP), a Schiff base synthesized and characterized for the first time, to the authors’ knowledge, as a novel inhibitor against corrosion of mild steel (MS) in hydrochloric acid solution.

HEMAP was characterized by some spectroscopic methods including High-Resolution Mass Spectrometry (HRMS), Proton Nuclear Magnetic Resonance (1H NMR), Carbon-13 (C13) nuclear magnetic resonance (13C NMR) and Fourier Transform Infrared Spectroscopy (FT-IR). Then, the inhibition efficiency of HEMAP on MS in a hydrochloric acid solution was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). To explain the inhibition mechanism, the surface charge, adsorption isotherms and thermodynamic parameters of MS in the inhibitor solution were studied.

EIS tests displayed that the highest inhibition efficiency was calculated approximately as 99.5% for 5 × 10⁻² M HEMAP in 1 M HCl solution. The adsorption of HEMAP on the MS surface was found to be compatible with the Langmuir model isotherm. The thermodynamic parameter results showed that the standard free energy of adsorption of HEMAP on the MS surface was found to be more chemical than physical.

This study is important in terms of demonstrating the performance of the first synthesized HEMAP molecule as an inhibitor against the corrosion of MS in acidic media. EIS tests displayed that the highest inhibition efficiency was calculated approximately as 99.5% for 5 × 10⁻² M HEMAP in 1 M HCl solution.

The purpose of the study is to identify factors influencing the continuance of use of non-halal certified cosmetics among Muslim university students in Malaysia.

The research framework was developed based on the stimulus–organism–response model. Self-administered questionnaires were distributed using a purposive sampling method among Muslim students in three universities in Malaysia. A total of 501 usable data were collected and analysed using Smart partial least squares.

The analysis revealed that celebrity endorsement positively influences attitude and brand image. Meanwhile, brand image has a positive effect on attitude and continuance of use of non-halal certified cosmetics. Additionally, attitude has a positive effect on the continuance of use behaviour. Regarding predictive power enhancement, brand image and attitude were found to have a mediation effect and sequential mediation effect on the relationship between celebrity endorsement and the continuance of use behaviour. Attitude weakens the relationship between attitude and the continuance of use of non-halal cosmetics among Muslim university students in Malaysia.

Findings will primarily benefit halal and non-halal cosmetic manufacturers providing stakeholders with fundamental predicting information related to customers’ continuance of use thus resulting in better marketing strategies.

This study is focused on predicting consumer behaviour towards halal products, as well as young Muslim consumers’ perspective towards non-halal cosmetics. Celebrity endorsement is introduced as a stimulus in the context of Muslim university students to predict their continuance of use behaviour of non-halal certified cosmetics. The investigation includes the moderating effect of religiosity for the relationship between attitude and continuance behaviour. Findings reveal the mediating effects of brand image and attitude as a mediator and sequential mediator for the relationship between celebrity endorsement and continuance of use behaviour. Contributions enrich the literature related to non-halal certified contexts.

This study aims to analyze the relationship between toxic leadership and exit, prosocial voice, neglect and defensive silence. Second, this study investigates the mediating role of loyalty in these relationships.

A cross-sectional survey design with a sample of 544 individuals was used in this study.

The results suggested that toxic leadership positively influences exit, defensive silence and neglect and negatively influences prosocial voice. In addition, loyalty was found to be a partial mediator of the studied relationships.

This study addresses different theoretical debates, namely, loyalty as an attitude or behavior and its role in individuals’ responses and the relationship between silence and voice.

Neste estudo, pretendeu-se analisar a relação entre a liderança tóxica e a saída, voz prosocial, negligência e silêncio defensivo. Foi também investigado o papel mediador da lealdade nestas relações.

Foi realizado um estudo transversal com uma amostra de 544 participantes.

Os resultados sugerem que a liderança tóxica influência positivamente a saída, o silêncio defensivo e a negligência. Sugerem também uma influência negativa da liderança tóxica na voz prosocial. Adicionalmente, verificou-se que a lealdade é uma mediadora parcial nestas relações.

Este estudo aborda diferentes debates teóricos, nomeadamente a lealdade como atitude ou comportamento, o seu papel nas respostas dos indivíduos e a relação entre silêncio e voz.

En este estudio, nos proponemos analizar la relación entre el liderazgo tóxico y la salida, la voz prosocial, la negligencia y el silencio defensivo. En segundo lugar, investigamos el papel mediador de la lealtad en estas relaciones.

En este estudio se utilizó un diseño de encuesta transversal con una muestra de 544 individuos.

Los resultados sugirieron que el liderazgo tóxico influye positivamente en la salida, el silencio defensivo y la negligencia e influye negativamente en la voz prosocial. Además, la lealtad resultó ser un mediador parcial de las relaciones estudiadas.

Este estudio aborda diferentes debates teóricos, a saber, la lealtad como actitud o comportamiento y su papel en las respuestas de los individuos y la relación entre silencio y voz.

The chemical plant (CP) maintenance industry has been under increasing pressure by process designers to demonstrate its evaluation and information management of model checking (MC) on the durability’s performance and design of plant control instrument. This main problem has been termed as imperfect maintenance actions (IMAs) level. Although IMAs have been explored in interdisciplinary maintenance environments, less is known about what imperfect maintenance problems currently exist and what their causes are, such as the recent explosion in the Beirut city (4 August 2020, about 181 fatalities). The aim of this paper is to identify how CP maintenance environments could integrate MC within their processes.

To achieve this aim, a comprehensive literature review of the existing conceptualisation of MC practices is reviewed and the main features of information and communication technology tools and techniques currently being employed on such IMA projects are carried out and synthesised into a conceptual framework for integrating MC in the automation system process.

The literature reveals that various CP designers conceptualise MC in different ways. MC is commonly shaped by long-term compliance to fulfil the requirement for maintaining a comfortable durability risk on imperfect maintenance schemes of CP projects. Also, there is a lack of common approaches for integrating the delivery process of MC. The conceptual framework demonstrates the importance of early integration of MC in the design phase to identify alternative methods to cogenerate, monitor and optimise MC.

Thus far, this study advances the knowledge about how CP maintenance environments can ensure MC delivery. This paper highlights the need for further research to integrate MC in CP maintenance environments. A future study could validate the framework across the design phase with different CP project designers.