A.M. Ahmed, E. Khamis and H.M. Abd El‐Fattah
Electrochemical measurements and corrosion tests were made at 30° using mild steel speciements immersed in sulphuric acid solutions without and with additions of procaine…
Abstract
Electrochemical measurements and corrosion tests were made at 30° using mild steel speciements immersed in sulphuric acid solutions without and with additions of procaine hydrochloride and tetracaine hydrochloride. Polarization curves indicated that these compounds act as cathodic inhibitors, that is, the cathodic curves were affected.
Andrew McPherson and Colin Martin
A contemporary review of the psychometric properties of the Buss‐Perry Aggression Questionnaire was undertaken to assess its suitability for an alcohol dependent population. Three…
Abstract
A contemporary review of the psychometric properties of the Buss‐Perry Aggression Questionnaire was undertaken to assess its suitability for an alcohol dependent population. Three criteria were used to try to achieve this: factor analysis; internal consistency reliability; and test‐retest reliability. Factor analysis revealed that its structure is remarkably consistent in a number of populations. Internal consistency reliability and test‐retest reliability results scores proved to be mainly above the recommended threshold. A conclusion was reached regarding these results that the Buss‐Perry Aggression Questionnaire is an effective screening tool for aggression in an alcohol dependent population.
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Abdelrahman Moukhtar Naser, Hamada Abd El - Wahab, Mohamed Abd El Fattah Moustafa El Nady, Abdelzaher E.A. Mostafa, Long Lin and Ahmed Galal Sakr
This paper aims to investigate the best methods of utilisation of reclaimed asphalt pavements (RAP) in Egypt, to determine the effect of using 100% RAP instead of using virgin…
Abstract
Purpose
This paper aims to investigate the best methods of utilisation of reclaimed asphalt pavements (RAP) in Egypt, to determine the effect of using 100% RAP instead of using virgin aggregates and asphalt; investigate the effect of thermoplastic elastomer polymer as asphalt modifier; and also improve the mechanical and physical characteristics and consequently improving the quality of asphalt paving, increasing service life of asphalt-paving and reducing costs.
Design/methodology/approach
Nano acrylate terpolymers were prepared with different % (Wt.) of and were characterised by Fourier transforms infrared (FTIR), for molecular weight (Mw), by thermo gravimetric analysis (TGA) and by transmission electron microscopy (TEM). A 4% (Wt.) of the prepared nanoemulsion terpolymer was mixed with virgin asphalt as a polymer modifier, to improve and reuse of the RAP. The modified binder was tested. The tests conducted include penetration, kinematic viscosity, softening point and specific gravity. Application of Marshall mix design types; hot mix asphalt (HMA), warm mix asphalt (WMA) and cold in place recycled (CIR). Four different mix designs used; control mix contained virgin asphalt by HMA, and the other three mix designs were polymermodified asphalt sample by HMA, WMA and CIR.
Findings
The research results showed that using 4 Wt.% of the prepared nanoemulsion terpolymer to produce hot mix asphalt (HMA) and warm mix asphalt (WMA) achieved higher stability compared to the control mix and cold in place recycled (CIR).
Research limitations/implications
This paper discusses the preparation and the characterisation of nanoemulsion and its application in RAPs to enhance and improve the RAP quality.
Practical implications
Nano-acrylate terpolymer can be used as a new polymer to modify asphalt to achieve the required specifications for RAP.
Originality/value
According to the most recent surveys, Europe produced 265 tonnes of asphalt for road applications in 2014, while the amount of available RAP was more than 50 tonnes. The use of RAP in new blended mixes reduces the need of neat asphalt, making RAP recycling economically attractive.
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H. Abd El‐Wahab, F. Abd El‐Hai, M. Abd El‐Fattah and L. Lin
Demands for coatings with superior technical characteristics have induced the use of composite coatings, which usually represent an extremely strong product. The resin blend…
Abstract
Purpose
Demands for coatings with superior technical characteristics have induced the use of composite coatings, which usually represent an extremely strong product. The resin blend technique is a simple and useful method for improving paint properties. Coal tar resins are the most economical coating extensively used in the industry; short oil‐length alkyd resins are usually used for air and force‐dry industrial coatings for metal surfaces. The purpose of this paper is to evaluate coating blends composed of these resins, in particular, the effects of short oil‐length alkyd additive on the properties of coal tar binder.
Design/methodology/approach
One way to achieve new types of binders is to make combinations of the existing ones, in an ideal case retaining the desirable properties of both. The alkyd has important properties over the original drying oil. To achieve the goal of improving coal tar resin properties, short oil‐length alkyd was blended with it. The prepared short oil‐length alkyd was characterised using IR and 1HNMR spectroscopy. The mixing ratio of short oil‐length alkyd with coal tar was up to 25 per cent. The compatibility of coating blend was characterised by scanning electron microscope. The physical, mechanical and chemical properties of the coating blend in addition to the corrosion resistance were determined according to ASTM methods.
Findings
In spite of a large number of synthetic resins being available for use in paint formulations, the alkyd resins surpassed all of them in versatility and low cost. The blend of short oil‐length alkyd resin with coal tar has yielded better coating blend properties. The coating blend showed significant enhancement of physical, mechanical and chemical properties such as gloss, drying time, adhesion, scratch hardness, acid and solvent resistance because the coating blend combines the properties of thermosetting and thermoplastic resins.
Research limitations/implications
Alkyd resins are the most extensively used synthetic polymers in the coating industry. Modification of coal tar blend based on other type of polyester resins could also be studied in order to assess the applicability of the coal tar blend system found for other applications.
Practical implications
These types of alkyd resins can be applied in other bitumen composites as additives and reinforce agent.
Originality/value
The paper shows how the low‐cost modified coal tar binder can be used for air and force‐dry industrial coatings for metal surfaces.
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Marwa Sallam, Iman Wali, Abd El Fattah Attia, Wael Lotfy, Amal El Taweel and Nayra Shaker Mehanna
Breast milk has been hypothesized to be a source of bacteria for the infant gut. This paper aims to search for probiotic bacteria among 415 isolates belonging to the Enterococcus…
Abstract
Purpose
Breast milk has been hypothesized to be a source of bacteria for the infant gut. This paper aims to search for probiotic bacteria among 415 isolates belonging to the Enterococcus, Lactobacillus, Streptococcus and Bifidobacterium genera recovered from breast milk of 50 lactating mothers and their respective infant stools, and then, determine whether their levels in stools vary with different modalities of breast feeding.
Design/methodology/approach
To prove that the isolates were probable probiotics, subtractive screening was done using three major selection criteria, namely, resistance to low pH, tolerance against bile salts and testing for their antimicrobial activity.
Findings
The three criteria were fulfilled by 31.7 and 31 per cent of the isolates recovered from mothers’ breast milk and infants’ stool specimens, respectively. The majority of probiotic strains, isolated from milk and infants’ stools were phenotypically identical, suggesting breast milk as their probable source. Moreover, there was a positive correlation between exclusive breast milk feeding and the number of probiotics in the infants’ stools.
Originality/value
Viable bacteria could be retrieved from breast milk of healthy women, not suffering from mastitis, by using different types of media and different cultivation conditions. Up to five different species belonging to the same genus could be isolated in the same specimen of whether milk or stools. Breast milk could be a source of probiotic bacteria for intestinal microflora of infants, which help improvement of infants’ gut and growth.
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Walid E. Elgammal, Essam M. Eliwa, Hosni A. Goomaa, Medhat E. Owda and H. Abd El-Wahab
This paper aims to focus on the synthesis of the macrocyclic complexes (Cu and Zn) and their applications as anticorrosive materials in epoxy paint formulation for surface coating…
Abstract
Purpose
This paper aims to focus on the synthesis of the macrocyclic complexes (Cu and Zn) and their applications as anticorrosive materials in epoxy paint formulation for surface coating application.
Design/methodology/approach
A selected macrocyclic Cu(II) and Zn(II) complexes were prepared via template synthesis and characterized using Fourier transform infrared, thermal gravimetric analysis, scanning electron microscope, flexibility, hardness and adhesion of coating films prepared using epoxy paint.
Findings
The corrosion resistance of the epoxy-painted films was improved due to the incorporation of the Zn and Cu complexes into the formulation.
Originality/value
It was found that the metal complex-based formulation with Cu(II) and Zn(II) had outperformed the sample blank.
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Nashwa Mostafa Saleh, Maha Mohammed Elsawy, Hamada Abd El-Wahab, Salem Salah Salem and Nour El-Din Abd El-Sattar
The purpose of this study is to develop a new protective coating formulation for industrial use, using benzodiazepine derivatives as double function additives.
Abstract
Purpose
The purpose of this study is to develop a new protective coating formulation for industrial use, using benzodiazepine derivatives as double function additives.
Design/methodology/approach
Benzodiazepine’s derivatives of types (3–5) were prepared and confirmed by infrared, Mass, 1H-Proton nuclear magnetic resonance (NMR) and 13C NMR spectra. The synthesized compound was physically incorporated in the alkyd paint formulation by pebble mill grinding until all particulates are smaller than 20 ums. The prepared coatings were applied by air spray on steel panels. The physical, mechanical characteristics, corrosion resistance and antimicrobial test of the prepared coatings were studied to evaluate the prepared compounds drawbacks.
Findings
The results of the mechanical and physical properties of the paint formulation revealed that the paint formulation incorporating benzodiazepines derivatives 3–5 performed best and improved corrosion-resistance and antibacterial activity tests.
Research limitations/implications
In alkyd paint, heterocyclic compounds are the most used antibacterial additives. Other functionalities of these compounds, such as corrosion inhibitors, might be studied to see if they are suited for these applications.
Practical implications
Because of the activity of various benzodiazepine derivatives, which may be attributable to the presence of some function groups such as sulfonamide aromatic amino NH2 group, and elements such as Sulphur, Nitrogen, Chlorine, in its chemical structure. As a result, paint compositions including these compounds as additives can be used as dual-purpose paint and for a variety of industrial applications.
Originality/value
The research demonstrates how a low-cost paint composition based on synthesized benzodiazepine derivatives 3–5 may be used as a dual-function paint for industrial use.
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Roma G. Elfadel, Hala M. Refat, H. Abdelwahab, Salem S. Salem, Mohamed A. Awad and M.A.M. Abdel Reheim
This paper aims to investigate the prepared modified alkyd and poly(ester-amide) (PEA) resins as antimicrobial and insecticide binders for surface coating applications.
Abstract
Purpose
This paper aims to investigate the prepared modified alkyd and poly(ester-amide) (PEA) resins as antimicrobial and insecticide binders for surface coating applications.
Design/methodology/approach
Salicylic diethanolamine and 4-(N, N-dimethylamino) benzylidene glutamic acid were prepared and used as new sources of polyol and dibasic acid for PEA and alkyd resins, then confirmed by: acid value, FT-IR and 1H-NMR. The coating performance of the resins was determined using measurements of physico-mechanical properties. The biological and insecticide activities of the prepared resins were investigated.
Findings
The tests carried out revealed that the modified PEA and alkyd enhanced both phyisco-mechanical and chemical properties in addition to the biological and insecticide activities. The results of this paper illustrate that the introduction of salicylic diethanolamine and 4-(N, N-dimethylamino) benzylidene glutamic acid within the resin structure improved the film performance and enhanced the antimicrobial activity performance of PEA and alkyd resins.
Research limitations/implications
The modified alkyd and PEA organic resins can be used as biocidal binders when incorporated into paint formulations for multiple surface applications, especially those that are exposed to several organisms.
Originality/value
Modified alkyd and PEA resins based on newly synthesized modifiers have a significant potential to be promising in the production and development of antimicrobial and insecticide paints, allowing them to function to restrict the spread of insects and microbial infection.
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Rania Miniesy and Hadia Fakhreldin
The formalisation – switch from the informal to the formal sector – of micro, small and medium enterprises (MSMEs) has serious ramifications on the Egyptian economy. This study…
Abstract
Purpose
The formalisation – switch from the informal to the formal sector – of micro, small and medium enterprises (MSMEs) has serious ramifications on the Egyptian economy. This study investigates the effect of the factors perceived by Egyptian informal entrepreneurs to encourage/deter formalisation on those entrepreneurs' intentions of formalising their MSMEs. Social media (SM) usage is a novel factor whose impact on the intention of formalisation is also examined.
Design/methodology/approach
The conceptual framework of the theory of planned behaviour (TPB) is used, and a logistic regression model is utilised. Relevant data were collected from self-assessment questionnaires of a sample of Egyptian informal female and young male entrepreneurs, who constitute the majority of informal entrepreneurs in Egypt.
Findings
Results reveal that for female entrepreneurs, only the support of the government and other institutions positively affects their intention of formalisation, whilst direct costs and lack of family support affect their intention negatively. For young male entrepreneurs, the number of employees and prospects of contract enforcement positively affect their intention of formalisation, whilst being involved in a trading activity affects it negatively. For both groups, higher levels of education and SM usage adversely affect their intention of formalisation. These varying results have a crucial policy implication: the one-size-fits-all public policies intended to stimulate formalisation might not work, and thus, more tailored policies are required.
Originality/value
Worldwide, research on the impact of SM on the formalisation of MSMEs is scant, if existent. In Egypt, research on MSMEs is limited, those focusing on the impact of SM on Egyptian MSMEs are even scarcer and those targeting SM's effect on their formalisation are absent.
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El Khashab G. Narmeen, Abd El-Wahab H., Albohy A.H. Salwa, Moustafa G.M. Fouda and Sharaby M. Carmen
This study aims to synthesize new cyclodiphosph(V)azane derivatives, 2,2,4,4-tetrachloro-1,3-di-[o-nitriyl]-2,4-di-[N-(pyrimidin-2-yl)benzenesulfonamide]-1,3,2,4…
Abstract
Purpose
This study aims to synthesize new cyclodiphosph(V)azane derivatives, 2,2,4,4-tetrachloro-1,3-di-[o-nitriyl]-2,4-di-[N-(pyrimidin-2-yl)benzenesulfonamide]-1,3,2,4- diazadiphosphetidine(H2L) ligand and their Fe(III) and Ag(I) metal complexes as insecticides for protective coatings.
Design/methodology/approach
The substitutes of cyclodiphosph(V)azane sulfonomide and their Fe(III), Ag(I) metal complexes were prepared and confirmed by a combination of elemental analyses, mass spectra, conductivity measurement-vis, FTIR, 1H,13C-NMR TGA, XRD and Docking investigation of the ligand and some complexes to verify their drug ability. The prepared compounds have been incorporated with a polyurethane (PU) coating formula. Gloss, scratch resistance, flexibility and adhesion are some of the coating attributes investigated; mechanical capabilities include impact resistance and shore hardness and physicochemical properties such as chemical resistance of coated PU samples are also investigated.
Findings
The results of the experiments revealed that all PU coatings based on the prepared compounds had good scratch resistance which varied from >1.8 to >2.2 kg. Gloss value varied from 85 to 95 and impact resistance from 1.4 to 2.0 (J), whereas the authors noticed that there was no effect of the prepared compounds in the flexibility and adhesion test. These PU coatings have excellent chemical resistance except the alkali resistance. Insecticide activities of the prepared compounds are promising for resistance to these insects. It was noticed that, metal complex > incorporated PU with Fe (III) metal complex > incorporated PU with ligand.
Originality/value
Insecticide paints based on cyclodiphosph(V)azane sulfonamide and their Fe(III), Ag(I) metal complexes as insecticide agents are novel.