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Article
Publication date: 30 May 2023

Rawid Banchuin

The purpose of this paper is to originally present the generic analytical models of memelement and inverse memelement with time-dependent memory effect.

33

Abstract

Purpose

The purpose of this paper is to originally present the generic analytical models of memelement and inverse memelement with time-dependent memory effect.

Design/methodology/approach

The variable order forward Grünwald–Letnikov fractional derivative and the memristor and inverse memristor models proposed by Fouda et al. have been adopted as the basis. Both analytical and numerical studies have been conducted. The applications to the candidate practical memristor and inverse memelements have also been presented.

Findings

The generic analytical models of memelement and inverse memelement with time-dependent memory effect, the simplified ones for DC and AC signal-based analyses and the equations of crucial parameters have been derived. Besides the well-known opposite relationships with frequency, the Lissajous patterns of memelement and inverse memelement also use the opposite relationships with the time. The proposed models can be well applied to the practical elements.

Originality/value

To the best of the authors’ knowledge, for the first time, the models’ memelement and inverse memelement with time-dependent memory effect have been presented. A new contrast between these elements has been discovered. The resulting models are applicable to the practical elements.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 42 no. 6
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 14 August 2019

Abdelaziz S. Fouda, Mohamed A. Ismail, Rabab M. Abou-shahba, Walaa A. Hussein, Esraa S. El-habab and Ashraf S. Abousalem

The purpose of this paper is to investigate three Arylfuranylnicotinamidine derivatives against corrosion of carbon steel (C-steel) in 1.0 M HCl by chemical and electrochemical…

97

Abstract

Purpose

The purpose of this paper is to investigate three Arylfuranylnicotinamidine derivatives against corrosion of carbon steel (C-steel) in 1.0 M HCl by chemical and electrochemical means. The inhibition efficiency (%IE) increases with increasing the dose of inhibitors. The tested compounds exhibited improved performance at elevated temperature, with %IE reaching 93 percent at 21 µM. Tafel polarization method revealed that the tested compounds act as mixed-type inhibitors. The inhibition action was rationalized due to chemical adsorption of inhibition molecules on C-steel surface following Temkin’s isotherm. Surface examination was carried out by AFM and FTIR techniques. Further, theoretical chemical approaches were used to corroborate the experimental findings.

Design/methodology/approach

Experimental and computational methods were applied to investigate the efficiency of these new compounds. These studies are complemented with spectral studies and surface morphological scan by AFM. The theoretical results indicate good correlation with experimental findings.

Findings

The tested derivatives are promising corrosion inhibitors for C-steel in the acid environment. The molecular scaffold of this class of compounds can be used to design new highly efficient inhibitors by screening its activity by modeling studies.

Originality/value

The studied compounds are safe inhibitors and greatly adsorbed on Fe surface. The action of compounds is enhanced with temperature, which means these compounds can be used in higher temperature systems. The new compounds are effective at very low concentration.

Details

Multidiscipline Modeling in Materials and Structures, vol. 15 no. 6
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 1 August 1989

A.S. Fouda, S.S Elkaabi and A.K. Mohamed

The inhibitive effect of some substituted phenyl n‐phenylcarbamates on corrosion of iron in 2N HCI have been studied using gaivanostatic polarization measurement. Studies carried…

26

Abstract

The inhibitive effect of some substituted phenyl n‐phenylcarbamates on corrosion of iron in 2N HCI have been studied using gaivanostatic polarization measurement. Studies carried out with different concentrations of the inhibitor indicated that the compounds act as a mixed inhibitor. The results indicate that the additives reduce the corrosion rate by way of adsorption through the oxygen atom of phenoxy group and nitrogen atom of NH group. The inhibitory character of the compounds depends upon the concentration of the inhibitor, as well as its chemical composition. The results of electrocapillary measurements are consistent with the electrochemical measurements. Thermodynamic parameters for absorption of inhibitors have been calculated and discussed.

Details

Anti-Corrosion Methods and Materials, vol. 36 no. 8
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 June 1994

A.A. Al‐Suhybani and I.H. Al‐Hwaidi

Introduction The corrosion of iron has been extensively studied in various media. In nitric acid solutions, the corrosion of iron is much faster than in other mineral acids at…

52

Abstract

Introduction The corrosion of iron has been extensively studied in various media. In nitric acid solutions, the corrosion of iron is much faster than in other mineral acids at comparable concentrations. This is attributed to an autocatalytic process involving some nitrogen oxides, nitrous acid and/or some iron complexes. At high nitric acid concentrations, passivation of iron takes place. The factors affecting the dissolution and the passivation processes are not fully understood. The effect of various inhibitors on the corrosion of iron in acid media has been studied. Thus Ammar et al. have studied the passivation of iron and the effect of some anions, e.g. Br− and I− on the passive film. The effect of amides as inhibitors for iron in nitric acid has been reported by Fouda and Gouda. These authors have found that the corrosion process is controlled by the reaction of amides with HNO3 and not by the surface reaction. The effect of aniline and some aminobenzoic acids on the rate of corrosion of iron has been reported. The present work is aimed at examining the efficiencies of some aniline substitutes as corrosion inhibitors for the corrosion of iron in concentrated nitric acid solution.

Details

Anti-Corrosion Methods and Materials, vol. 41 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 19 November 2021

Rawid Banchuin

The purpose of this paper is to compare the suitability of fractional derivatives in the modelling of practical capacitors. Such suitability refers to ability to provide the…

59

Abstract

Purpose

The purpose of this paper is to compare the suitability of fractional derivatives in the modelling of practical capacitors. Such suitability refers to ability to provide the analytical capacitance function that matches the experimental ones of each fractional derivative.

Design/methodology/approach

The analytical capacitance functions based on various fractional derivatives of both local and nonlocal types including the author’s have been derived. The derived capacitance functions have been simulated and compared with the experimental ones of aluminium electrolytic and electrical double layer capacitors (EDLCs).

Findings

This paper has found that any local fractional derivative with fractional power law-based relationship with the conventional one is suitable for modelling the aluminium electrolytic capacitor (AEC) by incorporating with the conventional capacitance definition. On the other hand, the author’s nonlocal fractional derivatives have been found to be more suitable than the others for modelling the EDLC by incorporating with the revisited definition of capacitance.

Originality/value

The proposed comparative analysis has been originally presented in this work. The criterion for local fractional derivative, to be suitable for modelling the AEC, has been found. The nonlocal fractional operators which are most suitable for modelling the EDLC have been derived where the unsuitable one has been pointed out.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 1
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 16 November 2021

Emad ElDin El-Katori and Nady Hashem

The purpose of this paper is to minimize corrosion-related pollution in the environment. From the lemongrass extract (LGE), the authors selected one of the best green inhibitors.

106

Abstract

Purpose

The purpose of this paper is to minimize corrosion-related pollution in the environment. From the lemongrass extract (LGE), the authors selected one of the best green inhibitors.

Design/methodology/approach

The corrosion and inhibition of mild steel in traditional acidification solutions were estimated by electrochemical measurements. The corrosion appearance was observed with scanning electron microscopy, atomic force microscopy micrographs and attenuated total reflectance infrared spectroscopy spectrum. The correlation was formed between the gained inhibition efficiency (IE)% from electrochemical measurements and certain quantum chemical parameters.

Findings

The results displayed that the IE was up to 90% when the LGE concentration was 300 ppm. The results confirmed that the theoretical experiments are very similar to the experimental observations.

Originality/value

For the first time, LGE was used as a cheap and safe corrosion inhibitor for mild steel corrosion in the acidification process. The mechanism of mild steel corrosion and anti-corrosion in acid solution has been suggested.

Details

Anti-Corrosion Methods and Materials, vol. 69 no. 1
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 12 March 2018

Samy Shaban, Abd Elaziz Fouda, Mohamed Elmorsi, Tarek Fayed and Omar Azazy

The purpose of this study is to inspect the corrosion inhibition of API N80 steel pipelines in uninhibited solution and inhibited with a synthesized surfactant compound…

252

Abstract

Purpose

The purpose of this study is to inspect the corrosion inhibition of API N80 steel pipelines in uninhibited solution and inhibited with a synthesized surfactant compound [N-(3-(dimethyl octyl ammonio) propyl) palmitamide bromide] (DMDPP), which is prepared through a simple and applicable method.

Design/methodology/approach

Weight loss was inspected at five different temperatures of 25°C, 30°C, 40°C, 50°C and 60°C Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation were used at room temperature. Density functional theory was used to study the relation between the molecular structure and inhibition theoretically.

Findings

Adsorption of the prepared DMDPP fits the Langmuir isotherm model. The inhibition efficiency of the prepared DMDPP amphipathic inhibitor is directly proportional to temperature increase. Polarization results reveal that the investigated DMDPP amphipathic compound behaves as a mixed-type inhibitor. EIS spectra produced one individual capacitive loop.

Originality/value

The originality is the preparation of cationic surfactants through a simple method, which can be used as corrosion inhibitors in oil production. The synthesized inhibitors were prepared from low-price materials. The work studied the behavior of the synthesized surfactants in inhibiting the corrosion of the steel in an acidic medium. Electrochemical and theoretical studies were presented, besides gravimetric and surface examination.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 2
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 April 2005

A.S. Fouda, A. Abd El‐Aal and A.B. Kandil

To show the effect of organic compounds containing O and N atoms on the corrosion inhibition of Cu in HNO3 and; the effect of some donating substituent groups on the corrosion…

407

Abstract

Purpose

To show the effect of organic compounds containing O and N atoms on the corrosion inhibition of Cu in HNO3 and; the effect of some donating substituent groups on the corrosion inhibition.

Design/methodology/approach

A range of published papers (1956‐1995), which aim to discuss the effect of organic compounds on the corrosion inhibition process. Two methods were used to determine the rate of corrosion, these methods were weight loss and polarisation. The effect of temperature and concentration were studied. The thermodynamic parameters for the process were computed and discussed.

Findings

Provides information about weight loss and polarisation methods and how to prepare the Cu samples before and after tests. This will provide many academics relevant information before teaching or researching duties.

Research limitation/implications

The paper may be using withdrawing substituting groups in addition to donating groups, this will improve the discussion, also the paper does not use the technique of impedance spectroscopy for comparison.

Practical implications

To use Cu alloy for comparison and to use other compounds with larger molecular weights.

Originality value

The use of some phthalimide derivatives as corrosion inhibitors for Cu in HNO3, provide more information on Cu corrosion for academic researchers and provide practical help for starting researchers.

Details

Anti-Corrosion Methods and Materials, vol. 52 no. 2
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 22 March 2011

A.S. Fouda, S.A. EL‐Sayyad and M. Abdallah

The purpose of this paper is to investigate the inhibiting properties of four N‐3‐hydroxyl‐2‐naphthoyl hydrazone derivatives in 0.5 M H2SO4 solution and to study the mechanism of…

321

Abstract

Purpose

The purpose of this paper is to investigate the inhibiting properties of four N‐3‐hydroxyl‐2‐naphthoyl hydrazone derivatives in 0.5 M H2SO4 solution and to study the mechanism of their action.

Design/methodology/approach

The effect of various parameters on the behavior of these inhibitors has been studied using the weight loss and polarization measurements.

Findings

The inhibiting action of the investigated compounds depends primarily on their concentration and molecular size. The compounds act as mixed type inhibitors and function via adsorption on carbon steel surface, which follows Frumkin adsorption isotherm. The addition of KI, KBr and KSCN to N‐3‐hydroxyl‐2‐naphthoyl hydrazone derivatives had a synergistic effect in enhancing the efficiency of corrosion inhibition.

Originality/value

This paper provides useful information regarding inhibition effect of N‐3‐hydroxyl‐2‐naphthoyl hydrazone derivatives and clarifies the role of the molecular structure and substituents on the inhibition efficiency of these investigated compounds on the corrosion of carbon steel in acidic solutions.

Details

Anti-Corrosion Methods and Materials, vol. 58 no. 2
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 September 1989

M.M. El‐Tagouri, M.R. Mostafa, H.M. Abu El‐Nader and G.M. Abu El‐Reash

The efficiency of some 2‐heterocarboxaldehyde‐2′‐pyridyl‐hydrazones as inhibitors for the acid dissolution of Al was studied by mass loss, hydrogen evolution and polarization…

17

Abstract

The efficiency of some 2‐heterocarboxaldehyde‐2′‐pyridyl‐hydrazones as inhibitors for the acid dissolution of Al was studied by mass loss, hydrogen evolution and polarization measurement techniques. The corrosion rate was measured in 2M HCI at different temperature and concentrations; maximum percentage protection (85%) was obtained at 103M for the compound containing oxygen atom. The activation energies were calculated for all the additives used. The rate constant decreases as the inhibition efficiency increases. The results show that the studied materials influencing both the cathodic and anodic process. The mechanism of inhibition was proposed on the basis of the formation of a protective monolayer by the inhibitors molecules on the metal surface according to Langmuir isotherm.

Details

Anti-Corrosion Methods and Materials, vol. 36 no. 9
Type: Research Article
ISSN: 0003-5599

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