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1 – 10 of 296
Article
Publication date: 1 August 1997

R.A. El‐Adly, Y.M. Moustafa and A.M.A. Omar

Acid sludge produced from regeneration of used lubricating oil was chemically treated in order to convert it in to a saleable product. Investigates treatment with different…

319

Abstract

Acid sludge produced from regeneration of used lubricating oil was chemically treated in order to convert it in to a saleable product. Investigates treatment with different inorganic formulations. Determines and discusses the optimum formulation composition. Characterizes the spectroscopic analysis, thermogravimetric and rheology behaviours, and hydrocarbon type analysis (asphaltene, oil and resin) of the extracted multicomponent resin (MCR‐1). Uses the MCR‐1 for the preparation of gilsonite varnish. The physico‐chemical properties of the latter were determined and compared with those of a standard gilsonite varnish. Concludes that treatment of acid sludge with different salt formulations provides a potentially lowest cost source of gilsonite varnish for news ink and also helps reduce an environmental problem created by re‐refining used oil.

Details

Pigment & Resin Technology, vol. 26 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 August 2004

A.M. El‐Masry, H.Y. Moustafa, A.I. Ahmed and A.F. Shaaban

New N‐halamine polymeric compounds were prepared by reacting cyanuric acid and polyacrylonitrile. Grafting of acrylonitrile monomer onto cotton linters was carried out and the…

Abstract

New N‐halamine polymeric compounds were prepared by reacting cyanuric acid and polyacrylonitrile. Grafting of acrylonitrile monomer onto cotton linters was carried out and the product was reacted with cyanuric acid and finally was chlorinated. Cyanoethylation of polyvinyl alcohol was performed using acrylonitrile monomer to give polyvinylcyanoethyl ether, which, in turn, was reacted with cyanuric acid. The biological activity of the various chlorinated compounds obtained was examined against Gram (+) and Gram (−) bacteria using columns and dishes methods. A high disinfecting power of the chlorinated compounds obtained was observed. Thus, the bacteria was deactivated after the first cycle without contact with the product. All of the compounds prepared were insoluble in water and most of inorganic solvents. These compounds were also found to be very stable and did not decompose to give any toxic compounds. Thus, the chlorinated compounds prepared had no harmful effects on humans.

Details

Pigment & Resin Technology, vol. 33 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 March 2006

H.Y. Moustafa

To prepare bioactive polymeric materials by grafting methods and characterisation of the biological activity of such materials.

Abstract

Purpose

To prepare bioactive polymeric materials by grafting methods and characterisation of the biological activity of such materials.

Design/methodology/approach

New bioactive polysaccharides were prepared by grafting of acrylonitrile onto water soluble starch and the resulted material was reacted with bioactive heterocyclic rings, converting to N‐halamine biocidal polymers by chlorination and to polyquats by converting it to quaternary ammonium salts using hydrochloric acid. The biological activity of the materials prepared against gram positive and gram negative bacteria was studied by three methods.

Findings

Most of the bioactive materials prepared showed high disinfecting power against bacteria.

Research limitations/implications

The bioactive materials were prepared by grafting of acrylonitrile onto starch and then reacting the resultant material with sulphadiazine. Many other heterocyclic rings that contain tertiary nitrogen atoms or amide group can also be used.

Practical implications

The new bioactive materials prepared can be used in disinfection of drinking water, swimming pools, etc.

Originality/value

The materials prepared and the use of such materials for disinfection were novel.

Details

Pigment & Resin Technology, vol. 35 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Open Access
Article
Publication date: 9 December 2022

José-María Romero-Rodríguez, María Soledad Ramirez-Montoya, Leonardo David Glasserman-Morales and Magdalena Ramos Navas-Parejo

The aim of this paper was to analyse the creative competence of students before and after a micro-learning experience carried out in a collaborative online international learning…

1305

Abstract

Purpose

The aim of this paper was to analyse the creative competence of students before and after a micro-learning experience carried out in a collaborative online international learning (COIL) environment between Spanish and Mexican university students in the field of education and entrepreneurship.

Design/methodology/approach

A single-group quasi-experimental design with pre-test and post-test measures was adopted. The composition of the group was natural and included a total of 57 students who participated in the COIL experience. The duration was three weeks, where students from both countries were linked together in the development of a micro-learning project. The creativity self-efficacy scale was used as a data collection instrument.

Findings

The micro-learning activities through COIL developed the creative competence of the participating students. In particular, the groups from both universities improved their scores on the creative competence in the post-test compared to the pre-test measure.

Research limitations/implications

The limitations of this study were linked to the sample loss of some cases, as some students did not complete the post-test measure. The main implication of the study was to demonstrate that COIL experiences are suitable for developing certain skills in students, such as creative competence or co-operative work.

Originality/value

COIL experiences break down the barriers of physical space and give students an active role, allowing them to fully develop competences and offering an intercultural perspective, which encourages open-mindedness and understanding of the world.

Details

Education + Training, vol. 65 no. 2
Type: Research Article
ISSN: 0040-0912

Keywords

Article
Publication date: 2 March 2022

Maryam Khashij, Mohammad Hossein Salmani, Arash Dalvand, Hossien Fallahzadeh, Fatemeh Haghirosadat and Mehdi Mokhtari

This paper aims to investigation of processes for Pb2+ elimination from water/wastewater as a significant public health issue in many parts of world. The removal of Pb2+ ions by…

Abstract

Purpose

This paper aims to investigation of processes for Pb2+ elimination from water/wastewater as a significant public health issue in many parts of world. The removal of Pb2+ ions by various nanocomposites has been explained from water/wastewaters. ZnO-based nanocomposites, as eco-friendly nanoparticles with unique physicochemical properties, have received increased attention to remove Pb2+ ions from water/wastewaters.

Design/methodology/approach

In this review, different ZnO-based nanocomposites were reviewed for their application in the removal of Pb2+ ions from the aqueous solution, typically for wastewater treatment using methodology, such as adsorption. This review focused on the ZnO-based nanocomposites for removing Pb2+ ions from water and wastewaters systems.

Findings

The ZnO-based nanocomposite was prepared by different methods, such as electrospinning, hydrothermal/alkali hydrothermal, direct precipitation and polymerization. Depending on the preparation method, various types of ZnO-based nanocomposites like ZnO-metal (Cu/ZnO, ZnO/ZnS, ZnO/Fe), ZnO-nonmetal (PVA/ZnO, Talc/ZnO) and ZnO-metal/nonmetal (ZnO/Na-Y zeolite) were obtained with different morphologies. The effects of operational parameters and adsorption mechanisms were discussed in the review.

Research limitations/implications

The findings may be greatly useful in the application of the ZnO-based nanocomposite in the fields of organic and inorganic pollutants adsorption.

Practical implications

The present study is novel, because it investigated the morphological and structural properties of the synthesized ZnO-based nanocomposite using different methods and studied the capability of green-synthesized ZnO-based nanocomposite to remove Pb2+ ions as water contaminants.

Social implications

The current review can be used for the development of environmental pollution control measures.

Originality/value

This paper reviews the rapidly developing field of nanocomposite technology.

Details

Pigment & Resin Technology, vol. 52 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 11 December 2019

Zhangyu Wu, Hongfa Yu, Haiyan Ma, Bo Da and Yongshan Tan

Coral aggregate seawater concrete (CASC) is a new type of lightweight aggregate concrete that is becoming widely used in reef engineering. To investigate the corrosion behavior of…

Abstract

Purpose

Coral aggregate seawater concrete (CASC) is a new type of lightweight aggregate concrete that is becoming widely used in reef engineering. To investigate the corrosion behavior of different kinds of rebar in CASC exposed to simulated seawater for 0-270 d, the electrochemical techniques, including linear polarization resistance (LPR) technique and the electrochemical impedance spectroscopy (EIS), were used in the present work.

Design/methodology/approach

The electrochemical techniques, including LPR technique and the EIS, were used in the present work.

Findings

Based on the time-varying law of linear polarization curves, self-corrosion potential (Ecorr), polarization resistance (Rp), corrosion current density (Icorr), corrosion rate (i), and the characteristics of EIS diagrams for different types of rebar in CASC, it can be found that the anti-corrosion property of them can be ranked as epoxy resin coated steel > 2205 duplex stainless steel (2205S) > 316 L stainless steel (316 L) > organic coated steel > ordinary steel. Additionally, the linear regression equation between Rp and charge transfer resistance (Rct) was established. Finally, the EIS corrosion standard of rebar was established from the LPR corrosion standard, which provides a direct standard for the EIS technique to determine the condition of rebar in CASC.

Originality/value

The linear regression equation between polarization resistance and charge transfer resistance was established. And the EIS corrosion standard of rebar was established from the LPR corrosion standard, which provides a direct standard for the EIS technique to determine the condition of rebar in CASC.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 9 August 2018

Bo Da, Hongfa Yu, Haiyan Ma and Zhangyu Wu

This paper aims to reduce the cost, limit the time and increase raw material source availability, coral aggregate seawater concrete (CASC) composed of coral, coral sand, seawater…

Abstract

Purpose

This paper aims to reduce the cost, limit the time and increase raw material source availability, coral aggregate seawater concrete (CASC) composed of coral, coral sand, seawater and cement can be widely used for the construction of ports, levees, airports and roads to achieve practical engineering values. However, the naturally porous coral structure and abundant Cl in the seawater and coral lead to extremely severe reinforcement corrosion for CASC. It is well known that Cl is the main cause of reinforcement corrosion in the marine environment. Therefore, it is necessary to research the reinforcement corrosion of CASC in the marine environment.

Design/methodology/approach

In this study, linear polarization resistance was adopted to test the linear polarization curves of reinforcement in CASC with different exposure times. Ecorr, Rp, Icorr and Vcorr were calculated according to the weak electrochemical polarization theory and Stern–Geary formula. The effects of concrete cover thickness, exposure time, reinforcement types and inhibitor on reinforcement corrosion in CASC were analysed. The reinforcement corrosion degradation rule was determined, which provided theoretical support for the durability improvement, security assessment, service life prediction and service quality control of CASC structures in marine islands and reef engineering.

Findings

The corrosion resistance was enhanced with increased concrete cover thickness, and the concrete cover thickness for organic new coated steel should be at least 5.5 cm to reduce the reinforcement corrosion risks in CASC structures. The corrosion resistance of different types of reinforcements followed the rule: 2205 duplex stainless steel > 316 stainless steel > organic new coated steel > zinc-chromium coated steel > common steel. In the early exposure stage, the anti-corrosion effectiveness of the calcium nitrate inhibitor (CN) was superior to that for the amino alcohol inhibitor (AA). With the extension of exposure time, the decreasing rate of anticorrosion effectiveness of CN was higher than that of AA.

Originality/value

Reinforcement corrosion of CASC in a marine environment was studied. Concrete cover thickness, exposure time, reinforcement type and inhibitor influenced the reinforcement corrosion were investigated. New technique of reinforcement anti-corrosion in marine engineering was proposed. Possible applications of CASC in marine engineering structures were suggested.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 27 November 2018

Homero Castaneda, Jorge Alamilla, Hongbo Liu, Marco Antonio Antonio Espinosa-Medina and Eliceo Sosa

The purpose of this paper is to develop a real-time methodology to detect damages in coating and metallic structure in buried pipelines by using DC bias added to AC signal under…

Abstract

Purpose

The purpose of this paper is to develop a real-time methodology to detect damages in coating and metallic structure in buried pipelines by using DC bias added to AC signal under field operation conditions, including cathodic protection.

Design/methodology/approach

Impedance measurements were performed on buried pipeline for different field conditions, to develop a methodology to detect and locate damages by impedance distribution along the metallic structure.

Findings

Field condition measurements were conducted as a pilot test on a buried steel pipeline segment with a diameter of 16 inches and length of 20 km. The frequency-based technology shows some differences but overall good behavior between impedance magnitudes vs localization of the interface changes at the soil-coating-steel interface at different frequencies using DC bias added to AC signal under field operation conditions, including cathodic protection.

Research limitations/implications

The methodology is not applicable to highly resistive soil or high degradation coatings.

Practical implications

In this work, we depict a methodology that describes real time monitoring technology for buried metallic structures using AC signal. This monitoring is capable to detect and locate real time damage occurrences on the pipe surface (coating break). Field measurements include different conditions, such as temperature, soil resistivity and soil physical structure and chemical composition.

Social implications

In consideration of the satisfied application in the field of the methodology, it is believed that it can be used for the monitoring of damages in pipes in areas with high consequences and hence pipe integrity can be increased.

Originality/value

This real-time methodology is based on the impedance distribution signal and the differential changes along the pipeline under operating conditions. The results showed good agreement with the proposed methodology, which is able to discriminate some situations inherent of field conditions by using different impedance measurements performed along ±10 km of buried steel pipeline and assuming the reference location as the cathodic protection set up.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 October 2005

A.M. El‐Masry

The preparation and characterisation of new bioactive polymeric materials.

Abstract

Purpose

The preparation and characterisation of new bioactive polymeric materials.

Design/methodology/approach

New bioactive polysaccharide were prepared by grafting of acrylonitrile onto water soluble starch and then reacting with bioactive heterocyclic rings. The biological activity, against bacteria, of the materials prepared was studied.

Findings

Some of the prepared bioactive materials show high disinfecting power against bacteria.

Research limitations/implications

The bioactive materials were prepared by grafting acrylonitrile onto starch and then reacting the resulting material with cyanuric acid and 2‐aminothiazole. Many other heterocyclic rings that contain tertiary nitrogen atom or amide nitrogen can also be used.

Practical implications

The new bioactive materials prepared can be used for disinfecting purposes.

Originality/value

Some of the materials prepared were used successfully in killing bacteria, as such, can be used as disinfecting materials.

Details

Pigment & Resin Technology, vol. 34 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 28 July 2022

Ahmed Mohamed Elbaz, Mohammad Soliman, Alamir Al-Alawi, Bassam Samir Al-Romeedy and Moustafa Mekawy

The purpose of this study is to investigate the perceived severity of service failure (PSSF) and service recovery strategies (SRSs) as antecedents of customer forgiveness (CF)…

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Abstract

Purpose

The purpose of this study is to investigate the perceived severity of service failure (PSSF) and service recovery strategies (SRSs) as antecedents of customer forgiveness (CF), customer reconciliation, negative word-of-mouth and re-patronage intention as outcomes across two Middle Eastern countries: Egypt and Oman.

Design/methodology/approach

A quantitative technique was used, using a questionnaire, to collect data from customers of the national airline companies of Egypt and Oman. The perspectives of 1,084 airline customers were analysed using partial least squares-structural equation modelling.

Findings

The results of this study show that service failure severity has a negative influence on the effectiveness of SRSs. In turn, proper SRSs strongly and positively affect both Egyptian and Omani CF. Furthermore, the findings of this study indicate that service failure habit plays an important role in increasing the negative influence of perceived service failure severity on Egyptian, but not Omani, CF. Overall, results suggest that CF differs considerably between Egyptians and Omanis.

Originality/value

This study developed and empirically examined a comprehensive conceptual model of the drivers and outcomes of CF of airline companies. This study provides academics with meaningful insights into how social and cultural differences between customers in different countries can result in sometimes dramatically different behaviours following a service failure.

目的

本研究在埃及和阿曼两个中东国家调查了感知的服务失败严重性(PSSF), 并将其作为服务恢复策略, 作为顾客宽恕, 顾客和解, 负面口碑和重购意向的前因变量。

设计/方法/方法

本研究采用定量方法, 使用问卷调查, 从埃及和阿曼国家航空公司的顾客中收集数据。使用PLS-SEM分析了1084个航空公司客户的观点。

结果

结果表明, 服务失败严重性对服务恢复策略的有效性有负面影响。相应地, 适当的服务恢复策略对埃及和阿曼顾客的宽恕度有强烈的积极影响。此外, 研究结果表明, 在埃及(而不是阿曼)的顾客中, 服务失败习惯对感知到的服务失败严重程度对宽恕的负面影响方面起着重要作用。总体而言, 结果表明, 埃及和阿曼顾客之间的顾客客户宽恕差异很大。

原创性/价值

本研究开发并实证检验了航空公司顾客宽恕的驱动因素和结果的综合概念模型。本研究为学界提供了有意义的见解, 即了解不同国家/地区的顾客之间的社会和文化差异如何导致服务失败后出现截然不同的行为。

Propósito

Este estudio analizó la gravedad percibida de los fallos del servicio de reclamaciones (PSSF) y quejas como antecedentes de respuesta a los clientes, la reconciliación con el mismo, el boca a boca negativo y la intención de patrocinio como resultados en dos países del Medio Oriente (MO): Egipto y Omán.

Diseño/metodología/enfoque

se empleó una técnica cuantitativa, utilizando un cuestionario, para recopilar datos de los clientes de las compañías aéreas nacionales de Egipto y Omán. Se analizaron las perspectivas de 1084 clientes de aerolíneas utilizando PLS-SEM.

Resultados

los resultados muestran que la gravedad de los fallos en el servicio tiene una influencia negativa en la efectividad de las estrategias del servicio de reclamaciones. Asimismo, las estrategias de este tipo afectan fuerte y positivamente sobre la empatía de los clientes egipcios y omaníes. Además, los resultados indican que los fallos en el servicio de quejas, juega un papel importante en el aumento de la influencia negativa de la severidad percibida sobre el servicio y la consideración a la hora de perdonar por parte del cliente egipcio, pero no en el omaní. En general, los resultados sugieren que el perdón del cliente difiere considerablemente entre egipcios y omaníes.

Originalidad/valor

el estudio se desarrolló y se implementó empíricamente sobre un modelo conceptual integrado de impulsores y resultados del perdón de los clientes de las compañías aéreas. El estudio brinda a los académicos información significativa sobre cómo las diferencias sociales y culturales entre los clientes en diferentes países pueden resultar en comportamientos a veces dramáticamente diferentes en los fallos en el servicio.

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