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Article
Publication date: 27 July 2018

Nivin M. Ahmed, Mostafa G. Mohamed, Reham H. Tammam and Mohamed R. Mabrouk

This study aims to apply novel anticorrosive pigments containing silica fume-phosphates (Si-Ph), which were prepared using core-shell technique by covering 80-90 per cent…

Abstract

Purpose

This study aims to apply novel anticorrosive pigments containing silica fume-phosphates (Si-Ph), which were prepared using core-shell technique by covering 80-90 per cent silica fume (core) with 10-20 per cent phosphates (shell) previously, to play dual functions simultaneously as anticorrosive pigments in coating formulations and as an anticorrosive admixture in concrete even if it is not present in the concrete itself. Two comparisons were held out to show the results of coatings on rebars containing core-shell pigments in concrete, and concrete admixtured with silica fume can perform a dual function as anticorrosive pigment and concrete admixture. The evaluation of corrosion protection efficiency of coatings containing core-shell pigments and those containing phosphates was performed.

Design/methodology/approach

Simple chemical techniques were used to prepare core-shell pigments, and their characterization was carried out in a previous work. These pigments were incorporated in solvent-based paint formulations based on epoxy resin. Different electrochemical techniques such as open-circuit potential and electrochemical impedance spectroscopy were used to evaluate the anticorrosive efficiency of the new pigments.

Findings

The electrochemical measurements showed that concrete containing coated rebars with core-shell pigments exhibited almost similar results to that of concrete admixtured with silica fume. Also, the anticorrosive performance of coatings containing Si-Ph pigments offered protection efficiency almost similar to that of phosphates, proving that these new pigments can perform both roles as anticorrosive pigment and concrete admixture.

Originality/value

Although the new Si-Ph pigments contain more than 80 per cent waste material, its performance can be compared to original phosphate pigments in the reinforced concrete.

Details

Pigment & Resin Technology, vol. 47 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 8 May 2018

Nivin M. Ahmed, Mostafa G. Mohamed and Walaa M. Abd El-Gawad

New types of phosphate pigments which are appropriate alternatives for hazardous chromate pigments have been prepared and evaluated. These new pigments were prepared via a…

Abstract

Purpose

New types of phosphate pigments which are appropriate alternatives for hazardous chromate pigments have been prepared and evaluated. These new pigments were prepared via a new technique named core-shell. The core-shell materials consist of at least two separate phases with different chemical compositions. Recently, these materials have become more significant because they have the advantage of gathering the properties of both cores and shells that help to overcome the defects that they might possess individually. The purpose of this research is to develop a modified silica fume-phosphate core-shell pigment that contains 80-90 per cent of waste material (silica fume) and at the same time can offer promoted mechanical and anticorrosive properties than silica fume and they can also be compared with phosphates. The pigments have shells of Zn, Mn, Zn.Mn phosphates comprising about 10-20 per cent.

Design/methodology/approach

The prepared core-shell pigments have been characterized using several methods, which have then been integrated in alkyd paint formulations. The physical and mechanical properties of dry films and their corrosion prevention using accelerated laboratory test in 3.5 per cent NaCl for 28 days are estimated.

Findings

This study showed that the performance of these new pigments is highly efficient in corrosion protection, and it can be a suitable alternative to phosphate pigments despite containing phosphates which does not exceed 20 per cent of the composition.

Practical implications

Waste materials were reused in paints and only simple modification was used; their effectiveness was high and can be compared with well-known pigments.

Originality/value

Silica-phosphate core-shell pigments are environmentally friendly pigments that can replace other hazardous pigments (e.g. chromates and phosphates) with almost the same quality in their performance.

Details

Pigment & Resin Technology, vol. 47 no. 3
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 28 June 2018

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…

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.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

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Abstract

Details

Explaining Growth in the Middle East
Type: Book
ISBN: 978-0-44452-240-5

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Article
Publication date: 28 May 2021

Mahmoud Abdelrahman Kamel, Mohamed El-Sayed Mousa and Randa Mohamed Hamdy

This study used data envelopment analysis (DEA) models to measure financial efficiency of twelve commercial banks listed in the Egyptian stock exchange (CBLSE), along with…

Abstract

Purpose

This study used data envelopment analysis (DEA) models to measure financial efficiency of twelve commercial banks listed in the Egyptian stock exchange (CBLSE), along with evaluating changes to the financial efficiency during the period 2017–2019.

Design/methodology/approach

The study used BCC-I, cross-efficiency, super-efficiency models, and Malmquist productivity index (MPI) to assess financial efficiency of the examined banks. The available data from both inputs and outputs were analyzed using R. studio V.I.3. 1056 software.

Findings

Out of twelve banks examined, only four banks were efficient under BCC-I model over different years of the study period; however, only one bank (CIB) appeared to be the most efficient compared to other peers in the study sample. Moreover, MPI results revealed decreased financial efficiency during the study period, due to the decreased technological innovation, except for HDB. Tobit regression results confirmed that total assets and total equity are significant factors impacted financial efficiency of CBLSE.

Practical implications

This study sheds light on the importance of evaluating financial efficiency of CBLSE to all stakeholders, to pinpoint weaknesses in banks' performance, and for evaluating financial policies and investment decisions.

Originality/value

Several studies sought to implement different models of DEA to assess banking performance in different regions of the world, but very few studies examined financial efficiency of banks. To the best of authors’ knowledge, this study is one of those few that addressed financial efficiency of banks in Egypt.

Details

International Journal of Productivity and Performance Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1741-0401

Keywords

Content available
Article
Publication date: 16 June 2021

Amira Mohamed Emara and Nashwa Mostafa Ali Mohamed

This paper aims to investigate the relationship between global economic fluctuations and human development through four transmission channels (foreign direct investment…

Abstract

Purpose

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.

Design/methodology/approach

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

Findings

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.

Originality/value

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.

Details

Review of Economics and Political Science, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2356-9980

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Article
Publication date: 22 October 2018

Kh.M. Mostafa, Heba Ameen, Mahmoud Morsy, Amal El-Ebissy, Mohamed Adel and Ali Salah

This study aims to explore the incorporation of starch nanoparticles (SNPs) in cross-linking formulation of cotton fabrics to see their impact on fabric performance like…

Abstract

Purpose

This study aims to explore the incorporation of starch nanoparticles (SNPs) in cross-linking formulation of cotton fabrics to see their impact on fabric performance like tensile strength, dry wrinkle recovery angles, elongation at break, degree of whiteness and increase in weight as well as durability.

Design/methodology/approach

SNPs of size around 80-100 nm were successfully prepared from native maize starch by Nano precipitation technique and confirmed instrumentally by scanning electron microscope (SEM), transmittance electron microscope (TEM), Fourier transformer infrared (FTIR) spectroscopy and particle size analyzer. The latter were incorporated in cross-linking formulation of cotton fabrics encompassing different concentrations of citric acid and sodium hypophosphite at different curing time and temperature in 100 ml distilled water to a wet pickup of ca. 85 per cent. The fabric samples were dried for 3 min at 85°C and cured at specified temperatures for a specified time intervals in thermo fixing oven according to pad-dry-cure method.

Findings

FTIR spectra and SEM micrograph signified the chemical structure and surface morphology of cotton fabric before and after finishing in absence and presence of SNPs. Cotton fabric samples finished in presence of SNPs showed a higher tensile strength, elongation at break, comparable dry wrinkle recovery angles and degree of whiteness than that finished in their absence. On the other hand, the enhancement in the aforementioned performance reflects the positive impact of incorporation of SNPs in textile finishing especially with strength properties; which are one of the important requirements for industrial fabrics that can be used widely in heavy-duty applications.

Research limitations/implications

SNPs with its booming effect with respect to biodegradability, reactivity and higher surface area can be used as a novel reinforcement permanent finish for cotton fabrics instead of more hazardous materials likes poly acrylate and monomeric compounds.

Practical implications

As SNPs biopolymers is one of the important reinforcement agents, so it was expected that it would minimize the great loss in strength properties during easy-care cotton finishing and improve the fabric performance.

Originality/value

The novelty addressed here is undertaken with a view to remediate some of the serious defects of easy-care cotton fabrics using poly carboxylic acids; especially with the great loss in strength properties by virtue of using SNPs as a permanent finish. Besides, to the authors’ knowledge, there is no published work so far concerning the use of SNPs as an innovative base for production of easy-care finished cotton textiles with high performance.

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Article
Publication date: 15 August 2016

Mohamed M. Mostafa and Mohaned Al-Hamdi

Evidence suggests that a growing number of consumers across the world are becoming more environmentally responsible in terms of their personal habits and lifestyles. In…

Abstract

Purpose

Evidence suggests that a growing number of consumers across the world are becoming more environmentally responsible in terms of their personal habits and lifestyles. In this paper, the authors aim to use both parametric and non-parametric econometric models to estimate Kuwaiti consumers’ willingness to pay (WTP) for environmental protection in Failaka island.

Design/methodology/approach

Contingent valuation methods based on log-logistic and log-normal regression models revealed that consumers in Kuwait are willing to pay a price premium of approximately 40 Kuwaiti dinars for environmental protection in Failaka island based on the double-bound dichotomous choice model.

Findings

Socio-economic variables have no significant influence on the respondent’s WTP. As expected income has a positive relationship with WTP and bid price has negative relationship with WTP to protect the environment in Failaka island.

Originality/value

This study highlight the fact that understanding consumers’ environmental-friendly behaviors may play an important role in formulating environmental policy changes to face complex problems as diverse as environmental pollution or environmental degradation.

Details

Tourism Review, vol. 71 no. 3
Type: Research Article
ISSN: 1660-5373

Keywords

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Article
Publication date: 13 November 2020

Tingting Liu, Sherif Mostafa, Sherif Mohamed and Tuan Son Nguyen

Cities are facing challenges with their smart city agenda due to tighter budget constraints, varied interests of different stakeholders and increasing needs of…

Abstract

Purpose

Cities are facing challenges with their smart city agenda due to tighter budget constraints, varied interests of different stakeholders and increasing needs of technological innovation. Therefore, cities are partnering with private organisations to advance smart city projects. This research critically analyses the existing research published on public-private partnerships (PPPs) for the development of smart city projects and aims to identify the emerging themes and recommend mechanisms and strategies for improved use of smart city PPPs.

Design/methodology/approach

The content/textual analysis was conducted on 52 research publications relating to PPP and smart city from 2001 to 2020. With the assistance of the Leximancer software, the related literature was systematically analysed and synthesised to present the emerging themes of PPP application within the smart city context.

Findings

The analyses reveal that smart city PPPs mainly concentrated on building new or improving existing infrastructure. The research identifies five themes on PPP application for smart city development: (1) Technological innovation integration and increased risk profile, (2) Smart citizen engagement and participatory governance, (3) Data sharing and information security, (4) Transformation of PPP process and approach and (5) PPPs for urban sustainability. This research consolidates these five themes in a proposed sustainable public-private-people partnership (PPPP) framework.

Originality/value

This research provides a new perspective on rethinking the extant PPP models by highlighting the emerging themes in the PPP application for smart city development. This study provides useful recommendations for smart city infrastructure project partnership and engagement among the public and private sectors, and the city residents.

Details

Built Environment Project and Asset Management, vol. 11 no. 1
Type: Research Article
ISSN: 2044-124X

Keywords

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Article
Publication date: 12 March 2018

Mostafa Mohamed Al Sayed and Michael Elnemais Fawzy

The purpose of this paper is to study the role of social factors that determine the length of stay in a mental hospital and also understand the main factors leading to the…

Abstract

Purpose

The purpose of this paper is to study the role of social factors that determine the length of stay in a mental hospital and also understand the main factors leading to the phenomena as a step to solve it.

Design/methodology/approach

A case-control cross-sectional observational study is performed which studies correlates for the lengthy stay in a mental hospital. The study population consists of two groups: Group A (94 patients), taken from the patients hospitalized for more than one year, further subdivided into schizophrenia and schizoaffective inpatient group and bipolar affective inpatient group; and Group B (94 patients), receiving their treatment at the outpatient clinic after being admitted for less than six months, this group was further subdivided into same categories as Group A.

Findings

The study showed that the positive score in positive and negative symptoms scale (PANSS) showed highly statistically significant (p<0.01) correlation with the length of hospital stay for the schizophrenic and schizoaffective patients in the inpatient group. The results showed no statistically significant difference (p>0.05) between the inpatient schizophrenic cases and the inpatient affective cases regarding the length of hospital stay.

Research limitations/implications

The linear regression model was used to understand the predictors of increased length of hospital stay. The linear regression analyzing the scale data of schizophrenic and schizoaffective patients found that the length of hospital stay for the schizophrenic and schizoaffective patients depends on the patient’s age and his positive PANSS score. On the other hand, linear regression model for bipolar affective patients in the study found no statistically significant attributes of the length of hospital stay.

Practical implications

The study found that the length of hospital stay for schizophrenic and schizoaffective patients depends on the patient’s age and his positive PANSS score.

Social implications

The need for this study stems from the large numbers of mental inpatients who have been lengthily admitted in mental health hospitals in Egypt, while trying to understand main factors leading to the phenomena as a step to solve it. The study found that there is a highly significant difference between inpatient group and outpatient group regarding the marital status, education level, and psychosocial class, with inpatient group having more single, illiterate, and very low social class cases.

Originality/value

Research in the area of chronic psychiatric hospitalization and its effect on the course and prognosis of mental illness is still scarce, especially in the Arab world; therefore, the research will open the door for further research efforts in the future with a larger sample of patients to study the pros and cons of deinstitutionalization taking into account the past experience of health systems in other countries.

Details

International Journal of Human Rights in Healthcare, vol. 11 no. 1
Type: Research Article
ISSN: 2056-4902

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