Ahmed A. ElShami, Stéphanie Bonnet, Mohamed Hussein Makhlouf, A. Khelidj and N. Leklou
This paper aims to evaluate the ability of Aubepine and Molokhia extract, obtained by cathodic electrochemical treatment (CET), to protect steel rebar against attack by chloride…
Abstract
Purpose
This paper aims to evaluate the ability of Aubepine and Molokhia extract, obtained by cathodic electrochemical treatment (CET), to protect steel rebar against attack by chloride ions in environment of reinforced concrete marine structures. The effect of Aubepine and Molokhia extract was investigated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques.
Design/methodology/approach
This experimental work has achieved particularity to compare the behaviour of two types of treatment (carbon steel treated one time by Aubepine extract and one time by Molokhia extract) submitted to the presence and absence of chloride ions.
Findings
The results obtained show that the extract solution of the plant could serve as an effective inhibitor for the corrosion of steel. Inhibition was found to increase with increasing concentration of Molokhia extract and for Aubepine extract maximum concentration is 1 g/L.
Research limitations/implications
Plant extracts and traditional medicinal herbs have become important as an environmentally acceptable, readily available and renewable source for wide range of inhibitors.
Originality/value
Aubepine and Molokhia extract are novel green plants extract as corrosion inhibiting coating for steel embedded in concrete. Aubepine is a genus of trees in the family Rosaceae and Molokhia is the leaves of Corchorus olitorius. Flavonoids content was found in both of Aubepine and Molokhia extract as green inhibitors for corrosion of metals.
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Mamta Sharma, Taruna Dubey and Hardeep Chahal
The purpose of this paper is threefold: first, to examine the influence of the quality of online classes on student satisfaction and student loyalty; second, to explore the…
Abstract
Purpose
The purpose of this paper is threefold: first, to examine the influence of the quality of online classes on student satisfaction and student loyalty; second, to explore the mediating role of student participation between online classes and student satisfaction; third, to examine the mediating role of student satisfaction between online classes and student loyalty.
Design/methodology/approach
The primary data is collected from the postgraduate students in Jammu and Kashmir, India. A descriptive research design was applied to collect the primary data via Google questionnaire with the COVID-19 pandemic in mind to maintain social distance.
Findings
The result reveals that online classes and student participation positively affect student satisfaction. Student participation is a partial mediator between online classes and student satisfaction, with 0.393 Variance Accounted For (VAF). In comparison, it is a full mediator between online classes and student loyalty with 0.96 VAF.
Research limitations/implications
The current study was restricted to postgraduate students, while future research could include research scholars, graduate students, and others. Only government institutions in Jammu and Kashmir were employed for the present study. The study may eventually be expanded to include private universities and more states.
Practical implications
The suggested approach can help teachers, students, policymakers and administrators. The study emphasizes the crucial elements of student engagement and happiness, which must be prioritized to improve online teaching and learning effectiveness and win over students' loyalty.
Originality/value
The study tested the conceptual framework of an integrated approach connecting online classes, student participation, student satisfaction and student loyalty. The study was conducted during the COVID-19 pandemic lockdown period, as it was the need of the hour to come out of such a crisis in the future. The present study can also provide a roadmap for transformation from physical to virtual classrooms.
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Boussouffi Mustapha and Amina Sabeur
This study aims to provide an in-depth analysis of entropy generation (EG) during natural convection within the annular space between confocal elliptic cylinders, with a specific…
Abstract
Purpose
This study aims to provide an in-depth analysis of entropy generation (EG) during natural convection within the annular space between confocal elliptic cylinders, with a specific focus on the influence of Brownian motion on nanofluid behavior.
Design/methodology/approach
A finite volume control method was used to conduct a detailed numerical analysis, examining the behavior of various nanofluids across a range of volume concentrations (2%–6%) and Rayleigh numbers. The study explores heat transfer (HT) and fluid flow mechanisms, particularly highlighting the role of nanoparticle Brownian motion in enhancing thermal conductivity.
Findings
The findings reveal that increased Rayleigh numbers significantly improve HT rates, while at lower Rayleigh values, EG is primarily governed by thermodynamic irreversibility. At higher Rayleigh numbers, this irreversibility plays a less dominant role in overall entropy production.
Originality/value
This study offers a novel perspective on the interplay between Rayleigh numbers, Brownian motion and EG, providing valuable insights for optimizing HT processes in engineering applications involving nanofluids.
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Yara Ahmed, Racha Ramadan and Mohamed Fathi Sakr
This paper aims to evaluate the progressivity of health-care financing in Egypt by assessing all five financing sources individually and then combining them to analyze the equity…
Abstract
Purpose
This paper aims to evaluate the progressivity of health-care financing in Egypt by assessing all five financing sources individually and then combining them to analyze the equity of the whole financing system.
Design/methodology/approach
Lorenz dominance analysis and Kakwani progressivity index were applied on data from 2010/2011 Household Income, Expenditure, and Consumption Survey and the National Health Accounts 2011 using Stata to evaluate the progressivity of each source of health-care finance and the financing system overall.
Findings
The data show that Egypt’s health-care system, which is largely financed by out-of-pocket (OOP) payments, is slightly regressive, with an overall Kakwani index of −0.079. The overall regressive effect was the result of three regressive sources (OOP payments, an earmarked cigarette tax and direct taxes), one proportional finance source (social health insurance) and two slightly progressive sources (indirect taxes and private health insurance). This shows that the burden of financing health care falls more on the poor. These results signal the need for reform of health-care financing in Egypt to reduce dependence on OOP payments to achieve more equitable financing.
Originality/value
The paper seeks to augment the literature on health-care financing in Egypt by calculating specific progressivity estimates for all five sources of financing the Egyptian health-care system and analyzing the overall equity of this financing system. It will, therefore, provide a benchmark for monitoring the equity of finance in the Egyptian health-care system in future studies and allow one to assess the impact of implemented financing reforms in the future on the level of progressivity of health system financing.
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Amin Bagheri and Mohammad Yamani douzi sorkhabi
The purpose of this paper is to investigate students' social networking strategies based on learning values in the social context of Iranian universities.
Abstract
Purpose
The purpose of this paper is to investigate students' social networking strategies based on learning values in the social context of Iranian universities.
Design/methodology/approach
This research has used the case study method to investigate students’ networked learning (NL) strategies among students of four different universities in the context of Iran. They were explored by semistructured in-depth interviews about the nature or current conditions of their study life. The data were analyzed by the qualitative analysis method based on the systematic approach of Strauss and Corbin (1998).
Findings
The researchers in this study found the special concept of NL in the social context: “NL as a continuous process of thinking to understand the environment through multiple/ diverse careers of learning knowledge and skills for environmental modeling towards creating added-value.” According to this definition, various networked strategies were identified as follows: 1) interactive and multidimensional searching, 2) multidimensional studying and learning, 3) environmental and social management, 4) studying and social wandering.
Research limitations/implications
Designing dynamic curriculum, which integrates various careers of learning, multidimensional knowledge and abilities and subject matters with environmental events and social structures of the society. Given the exploratory nature of the research, the paper cannot provide empirically justified findings.
Originality/value
The research had identified diverse approaches of networking strategies, which do not appear just as a positive instrument to improve learning conditions. However, there is such an extreme degree of social wandering among students in universities that makes their efforts useless.
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Rabab M. Nasser and Nora M. Masmali
Plant development and use as green corrosion inhibitors are already recognized as one of the most environmentally friendly and effective protocols. In recent years, efforts have…
Abstract
Purpose
Plant development and use as green corrosion inhibitors are already recognized as one of the most environmentally friendly and effective protocols. In recent years, efforts have been made to find green corrosion inhibitors as an alternative to synthetic inhibitors for metals in acid medium. This paper aims to report the investigation of use of aqueous extracts of Tamarindus Indica as green inhibitors for corrosion of metals within different circumstances.
Design/methodology/approach
The use of Tamarindus Indica extracts (leaves, stem, fruit pulp and fruit husk) as corrosion inhibitors for mild steel and aluminum in different mediums (HCl, H2SO4, formic acid and citric acid) at different temperatures was investigated.
Findings
The inhibitory efficiency of Tamarindus Indica extracts increases with increasing concentration and decreases with increasing temperature. Langmuir is the adsorption isotherm, and the extract (inhibitor) is a mixed-type inhibitor (physisorption and chemisorption).
Practical implications
Tamarindus extracts (leaves, stem, fruit pulp and fruit husk) are effective inhibitors and can be used to protect metals from corrosion at different circumstances.
Originality/value
To the best of the authors’ knowledge, this is the first review that discusses the use of Tamarindus Indica extracts as corrosion inhibitors for metals.
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Nivin M. Ahmed, Mostafa G. Mohamed and Walaa M. Abd El-Gawad
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…
Abstract
Purpose
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.
Design/methodology/approach
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).
Findings
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.
Originality/value
Core-mutual shells structured pigments were prepared for improving the corrosion resistivity of the organic coatings as a new trend in anticorrosive pigments.
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Mostafa G. Mohamed, Nivin M. Ahmed and Walaa M. Abd El-Gawad
Using organic coatings serves as a key method to protect metal structures against corrosion. Attempts have been made to improve the corrosion inhibition of the coatings using…
Abstract
Purpose
Using organic coatings serves as a key method to protect metal structures against corrosion. Attempts have been made to improve the corrosion inhibition of the coatings using novel types of pigments. This study aims to study the application of organic coatings containing rice straw (RS) waste as anticorrosive pigment for corrosion protection of reinforced steel. The RS was used by precipitating a thin layer of ferrite pigments on its surface to improve their characteristics and corrosion resistance activity.
Design/methodology/approach
The evaluation of corrosion behavior of coated reinforced steel with paints containing these novel pigments is reported using different electrochemical methods.
Findings
The coatings containing the new prepared RS-ferrite pigments offered good corrosion protection, and coatings containing RS-ZnFe showed the best protection performance.
Originality/value
This paper introduces novel method to prepare treated RS without any burning and to play the role of pigments in anticorrosive paint formulations based on its silica content.
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This study aims to provide a timely review concerning the determinants and economic consequences of fair value reporting in real estate industry, as these topics have been gaining…
Abstract
Purpose
This study aims to provide a timely review concerning the determinants and economic consequences of fair value reporting in real estate industry, as these topics have been gaining momentum in accounting literature recently.
Design/methodology/approach
Diverse editorial sources (e.g. Elsevier, Emerald, Meridian Allenpress, Springer, Sage, Taylor & Francis and Wiley-Blackwell) were consulted to identify relevant studies for this review. Keywords used to collect studies include “fair value” and “IAS 40” or “investment property” and “fair value or “fair value and real estate.” This search yields 33 studies published between 2009 and 2023.
Findings
The synthesis of reviewed papers suggests that studies were mainly conducted in the European countries after the mandatory adoption of international financial reporting standards (IFRS) in 2005 and the Australian setting. The first stream of research deals with the choice of fair value approach. Reported empirical findings suggest that corporate size and market-to-book ratio are negatively associated with fair value choice, whereas ownership dispersion increases the likelihood of choosing fair value approach. The empirical evidence concerning the determinants of fair value magnitude suggests the type of appraiser represents a key predictor of the extent of fair value use. The second stream of research examines the impact of fair value reporting in real estate industry. Findings suggest that empirical evidence is still limited with respect to creditors, managers and financial analysts; fair value reporting is generally associated with higher level of value relevance for investors; and the use of Level 3 inputs in fair value estimates for investment properties is associated with high degree of estimation uncertainty for external auditors leading to increased audit risk and fees.
Practical implications
With respect to regulators, this review emphasizes that the beneficial impacts of fair value reporting are linked to institutional characteristics (e.g. legal system, the degree of market development), the reliability concerns regarding fair value estimates and the independence of appraiser. Because real estate industry is generally characterized by the lack of active market, regulators may adopt regulations requiring the independence external appraiser.
Originality/value
This literature review represents a historical record and an introduction for accounting scholars, in emerging economies and other settings, where fair value accounting has gained wide acceptance among the investment community. It also offers guidance for future research avenues.
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Mayya Ziganshina, Sergey Stepin, Sergey Karandashov and Veronika Mendelson
The purpose of this paper is to search for toxic anticorrosive pigments’ substitute in protective coatings is one of the important tasks that the specialists in the field of steel…
Abstract
Purpose
The purpose of this paper is to search for toxic anticorrosive pigments’ substitute in protective coatings is one of the important tasks that the specialists in the field of steel corrosion face.
Design/methodology/approach
One of the ways to solve the problem of metal corrosion is to use complex oxides as pigments, which are characterized as low-toxic compounds and possess the ability to inhibit corrosion.
Findings
In the production of ferrites, it is possible to use production waste as raw material, and that makes it possible to reduce the price of the resulting product and solve environmental problems simultaneously.
Originality/value
Permanent growth of world production is accompanied by the increasing environment corrosiveness, associated with the intensification of air, water basin and soil pollution by industrial waste. This, as well as the continuously increasing operated metal stock, has recently made the tendency of metals’ total loss from corrosion steadily increasing. All of this points to the importance of studying corrosion processes and the systematic and effective fight against metal corrosion.