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Article
Publication date: 1 August 1988

Awad I. Ahmed, S.N. Basahel and R.M. Khalil Chemistry

The inhibitive effect of some morpholine and thiosemicarbazide derivatives on the dissolution of aluminium in 2M HCI has been investigated by using thermometric, weight loss and…

59

Abstract

The inhibitive effect of some morpholine and thiosemicarbazide derivatives on the dissolution of aluminium in 2M HCI has been investigated by using thermometric, weight loss and hydrogen evolution techniques. The effect of the inhibitors on the protection efficiency and the corrosion rate were determined at various inhibitor concentrations and temperatures. It was observed that the percentage inhibition of aluminium increases with the increase of inhibitor concentration and decreases with rise of reaction temperature. Retardation of dissolution is due to weak adsorption of the additives on the metal surface. The order of inhibition efficiency of the inhibitors used depends on the number of adsorption sites in the molecule, their charge density and molecular size.

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Anti-Corrosion Methods and Materials, vol. 35 no. 8
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 24 April 2024

Ali Hassanzadeh, Ebrahim Ghorbani-Kalhor, Khalil Farhadi and Jafar Abolhasani

This study’s aim is to introduce a high-performance sorbent for the removal of both anionic (Congo red; CR) and cationic (methylene blue; MB) dyes from aqueous solutions.

23

Abstract

Purpose

This study’s aim is to introduce a high-performance sorbent for the removal of both anionic (Congo red; CR) and cationic (methylene blue; MB) dyes from aqueous solutions.

Design/methodology/approach

Sodium silicate is adopted as a substrate for GO and AgNPs with positive charge are used as modifiers. The synthesized nanocomposite is characterized by FTIR, FESEM, EDS, BET and XRD techniques. Then, some of the most effective parameters on the removal of CR and MB dyes such as solution pH, sorbent dose, adsorption equilibrium time, primary dye concentration and salt effect are optimized using the spectrophotometry technique.

Findings

The authors successfully achieved notable maximum adsorption capacities (Qmax) of CR and MB, which were 41.15 and 37.04 mg g−1, respectively. The required equilibrium times for maximum efficiency of the developed sorbent were 10 and 15 min for CR and MB dyes, respectively. Adsorption equilibrium data present a good correlation with Langmuir isotherm, with a correlation coefficient of R2 = 0.9924 for CR and R2 = 0.9904 for MB, and kinetic studies prove that the dye adsorption process follows pseudo second-order models (CR R2 = 0.9986 and MB R2 = 0.9967).

Practical implications

The results showed that the proposed mechanism for the function of the developed sorbent in dye adsorption was based on physical and multilayer adsorption for both dyes onto the active sites of non-homogeneous sorbent.

Originality/value

The as-prepared nano-adsorbent has a high ability to remove both cationic and anionic dyes; moreover, to the high efficiency of the adsorbent, it has been tried to make its synthesis steps as simple as possible using inexpensive and available materials.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 12 August 2024

Ali Hassanzadeh, Ebrahim Ghorbani Kalhor, Khalil Farhadi and Jafar Abolhasani

This study aims to investigate the efficacy of Ag@GO/Na2SiO3 nanocomposite in eliminating As from aqueous solutions. Employing response surface methodology, the research…

15

Abstract

Purpose

This study aims to investigate the efficacy of Ag@GO/Na2SiO3 nanocomposite in eliminating As from aqueous solutions. Employing response surface methodology, the research systematically examines the adsorption process.

Design/methodology/approach

Various experimental parameters including sample pH, contact time, As concentration and adsorbent dosage are optimized to enhance the As removal process.

Findings

Under optimized conditions, the initial As concentration, contact time, pH and adsorbent dosage are determined to be 32 ppm, 50 mins, 6.5 and 0.4 grams, respectively. While the projected removal of As stands at 97.6% under these conditions, practical application achieves a 93% removal rate. Pareto analysis identifies the order of significance among factors as follows: adsorbent dosage > contact time > pH > As concentration.

Practical implications

This study highlights the potential Ag@GO/Na2SiO3 as a promising adsorbent for efficiently removing industrial As from aqueous solutions, and it is likely to have a good sufficiency in the filtration of water and wastewater treatment plans to remove some chemical pollution, including paints and heavy metals.

Originality/value

The simplicity of the nanocomposite preparation method without the need for advanced equipment and the cheapness of the raw materials and its potential ability to remove As are the prominent advantages of this research.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 December 2003

A.M. Abdel‐Gaber, N. Khalil and A. Abou El‐Fetouh

The dissolution behaviour of steel in 1 N solutions of HCl, H2SO4 and HClO4 acid containing 10 per cent (v/v) ethanol was investigated at 30‐60°C using gas volume measurements…

835

Abstract

The dissolution behaviour of steel in 1 N solutions of HCl, H2SO4 and HClO4 acid containing 10 per cent (v/v) ethanol was investigated at 30‐60°C using gas volume measurements, polarisation and electrochemical impedance spectroscopy techniques. The data revealed that the rate of corrosion decreased in the order Cl>SO42−>ClO4. The corrosion mechanism of the acid dissolution for steel at low pH was found to be dependent on the counter ion present. The mechanism was discussed on the basis that the acid anion is first adsorbed on the steel surface, followed by the formation of a surface complex in the anodic process and finally the complex was desorbed from the surface. In general, if the adsorbed anion or the surface complex was stable, the corrosion of steel was suppressed. The calculated values of the activation energy for the steel in different acid indicated that the dissolution process proceeded via similar mechanisms.

Details

Anti-Corrosion Methods and Materials, vol. 50 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 April 2001

H.A. Abdel‐Hakim Ali, A.A. Attia, A.N. Al‐Masri and A.M. Baraka

This article presents the galvanostatic anodic oxidation of two types of stainless steel alloys, ferritic (15.03% Cr) and austenitic (20.45% Cr, 8.37% Ni), in molten NaNO3‐KNO3

1029

Abstract

This article presents the galvanostatic anodic oxidation of two types of stainless steel alloys, ferritic (15.03% Cr) and austenitic (20.45% Cr, 8.37% Ni), in molten NaNO3‐KNO3 eutectic mixture at different temperatures ranging from 673‐873K. At a temperature of 673K the shape of polarization curves for the alloys is complex, while at higher temperatures it is simple. The passivity potential range was calculated as the difference between the passivation potential, Ep, and the breakdown potential, Eb. The value of Eb – Ep decreases with the increase of temperature. The amount of iron, chromium and nickel dissolved in the melt was determined after each experiment using atomic absorption spectroscopy. The composition and structure of the corrosion products formed on the surface of electrodes were examined by X‐ray diffraction analysis. Corrosion parameters derived from the polarization curves are calculated; these are: polarization resistance at low current densities, Rp, exchange current density, io, corrosion current density, icorr, passivation current density, ip. It was found that the increase of temperature increases io, icorr, and ip while Rp, decreases. From these results it was found that, under the given conditions, the austenitic stainless steel alloy is more corrosion resistant than the ferritic one. The activation energy of corrosion was estimated for the two alloys.

Details

Anti-Corrosion Methods and Materials, vol. 48 no. 2
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 September 1985

This report is taken from the recently published 1984 Annual Report of the International Tin Research Council, Fraser Road, Greenford Middx

53

Abstract

This report is taken from the recently published 1984 Annual Report of the International Tin Research Council, Fraser Road, Greenford Middx

Details

Pigment & Resin Technology, vol. 14 no. 9
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 April 1995

Sh.A. El‐Shazly, A.A. Zaghloul, M.T. Mohamed and R.M. Abdullah

The results of the corrosion of metals and alloys with the use of solvent mixtures covering a wide range of compositions are limited in the literature. These mixed solvent systems…

39

Abstract

The results of the corrosion of metals and alloys with the use of solvent mixtures covering a wide range of compositions are limited in the literature. These mixed solvent systems possess a wide range of viscosity, dielectric constant and acid‐base properties. With this view, a kinetic study on the corrosion of metals in different aquo‐organic solvent systems has been undertaken. The corrosion of metals and alloys is strongly affected by the presence of water, the latter being found to have a passivating effect and sometimes a passivity breakdown effect. It is therefore of much interest to study the influence of varying water concentration on the corrosion and electrochemical behaviour of metal and alloys. The present work is a continuation of our studies on the kinetic of corrosion of metals in mixed aqueous‐organic solvents. Also, the corrosion rates are correlated to the dielectric constant and the total number of moles (n1 + n2) of water and ethylene glycol. This latter new correlation is described by El‐Shazly et al. for calculating the chemical potential (Δμ*) from kinetic data and molar thermodynamic excess functions for binary mixtures.

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Anti-Corrosion Methods and Materials, vol. 42 no. 4
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: 1 March 1990

M.N. Moussa, M.M. El‐Tagoury, A.A. Radi and S.M. Hassan

Inhibition of carboxylic acids of aluminium corrosion in hydrochloric acid and sodium hydroxide solutions has been studied using weight‐loss and hydrogen evolution methods. The…

137

Abstract

Inhibition of carboxylic acids of aluminium corrosion in hydrochloric acid and sodium hydroxide solutions has been studied using weight‐loss and hydrogen evolution methods. The order of inhibition action of aromatic acids depends on the number and position of the carboxylic groups and the other substituents in the benzene ring. Increase of the chain length increases the inhibiting power of aliphatic acids. The inhibition efficiency in NaOH is higher than that in HCI solutions. The action of inhibition was discussed in terms of the chemical structure of the inhibitors.

Details

Anti-Corrosion Methods and Materials, vol. 37 no. 3
Type: Research Article
ISSN: 0003-5599

Available. Open Access. Open Access
Article
Publication date: 12 July 2024

Osama Habbal, Ahmad Farhat, Reem Khalil and Christopher Pannier

The purpose of this study is to assess a novel method for creating tangible three-dimensional (3D) morphologies (scaled models) of neuronal reconstructions and to evaluate its…

242

Abstract

Purpose

The purpose of this study is to assess a novel method for creating tangible three-dimensional (3D) morphologies (scaled models) of neuronal reconstructions and to evaluate its cost-effectiveness, accessibility and applicability through a classroom survey. The study addresses the challenge of accurately representing intricate and diverse dendritic structures of neurons in scaled models for educational purposes.

Design/methodology/approach

The method involves converting neuronal reconstructions from the NeuromorphoVis repository into 3D-printable mold files. An operator prints these molds using a consumer-grade desktop 3D printer with water-soluble polyvinyl alcohol filament. The molds are then filled with casting materials like polyurethane or silicone rubber, before the mold is dissolved. We tested our method on various neuron morphologies, assessing the method’s effectiveness, labor, processing times and costs. Additionally, university biology students compared our 3D-printed neuron models with commercially produced counterparts through a survey, evaluating them based on their direct experience with both models.

Findings

An operator can produce a neuron morphology’s initial 3D replica in about an hour of labor, excluding a one- to three-day curing period, while subsequent copies require around 30 min each. Our method provides an affordable approach to crafting tangible 3D neuron representations, presenting a viable alternative to direct 3D printing with varied material options ensuring both flexibility and durability. The created models accurately replicate the fidelity and intricacy of original computer aided design (CAD) files, making them ideal for tactile use in neuroscience education.

Originality/value

The development of data processing and cost-effective casting method for this application is novel. Compared to a previous study, this method leverages lower-cost fused filament fabrication 3D printing to create accurate physical 3D representations of neurons. By using readily available materials and a consumer-grade 3D printer, the research addresses the high cost associated with alternative direct 3D printing techniques to produce such intricate and robust models. Furthermore, the paper demonstrates the practicality of these 3D neuron models for educational purposes, making a valuable contribution to the field of neuroscience education.

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