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Article
Publication date: 1 April 2002

A. Dafali, B. Hammouti, R. Touzani, S. Kertit, A. Ramdani and K. El Kacemi

The inhibition of the copper corrosion in aerated 3 per cent sodium chloride solution was studied by using electrochemical polarisation, weight loss and impedance…

Abstract

The inhibition of the copper corrosion in aerated 3 per cent sodium chloride solution was studied by using electrochemical polarisation, weight loss and impedance measurements in the presence of different concentration of synthesised bipyrazolic compounds: N,N‐bis (3,5‐dimethylpyrazol‐1‐ylmethyl) butylamine (bipy1); N,N‐bis (3,5‐dimethylpyrazol‐1‐ylmethyl) allylamine (bipy2); N,N‐bis (3,5‐dimethylpyrazol‐1‐ylmethyl) ethanolamine. (bipy3); N,N‐bis (3,5‐dimethylpyrazol‐1‐ylmethyl) cyclohexylamine (bipy4); N,N‐bis (3‐carbomethoxy‐5‐methylpyrazol‐1‐ylmethyl) cyclohexylamine (bipy5); N,N‐bis(3‐carboethoxy‐5‐methylpyrazol‐1‐ylmethyl) cyclohexylamine (bipy6). The inhibition efficiencies obtained from cathodic Tafel plots, polarisation resistance and weight loss are in good agreement with electrochemical impedance spectroscopy (EIS) measurements. All these additives were found to be excellent inhibitors of copper corrosion. The difference in inhibition efficiencies of these inhibitors was not big, but the optimum concentration for maximum efficiency was slightly dependent on the substitution of each molecule. The studied molecules act as mixed‐type inhibitors. Detailed study of bipy1 shows that the maximum inhibition efficiency revolves around 99 per cent from 5×10−4 M of inhibitor. This latter adsorbs on the copper surface according to the Frumkin isotherm model. The inhibition efficiency of bipy1 decreases with the rise of temperature in the range 25 – 60°C.

Details

Anti-Corrosion Methods and Materials, vol. 49 no. 2
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 December 2004

M. Elayyachy, M. El Kodadi, B. Hammouti, A. Ramdani and A. Elidrissi

The inhibition of corrosion of steel in 1 M HCl solution by newly synthesised pyrazole derivatives has been studied by weight loss and polarisation techniques at 308°K…

Abstract

The inhibition of corrosion of steel in 1 M HCl solution by newly synthesised pyrazole derivatives has been studied by weight loss and polarisation techniques at 308°K. Its inhibitory power is compared to N,N′‐bis(3,5‐dimethylpyrazol‐1‐yl‐methyl)‐pentanolamine (Bipyr). The results obtained reveal that tripyrazole exhibits a good protection. Inhibition is found to increase with increase in inhibitor concentration. The inhibition behaviour of the compound has been explained on the basis of molecule size and charge density of adsorption active centres. The adsorption phenomenon obeys the Langmuir adsorption isotherm model.

Details

Pigment & Resin Technology, vol. 33 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 June 2002

A. El Ouafi, B. Hammouti, H. Oudda, S. Kertit, R. Touzani and A. Ramdani

The inhibition of the corrosion of the mild steel in 1M HCl by new bipyrazolic compounds has been studied by weight loss, electrochemical polarisation and electrochemical…

Abstract

The inhibition of the corrosion of the mild steel in 1M HCl by new bipyrazolic compounds has been studied by weight loss, electrochemical polarisation and electrochemical impedance spectroscopy (EIS) measurements. Results obtained reveal that these compounds are very good inhibitors. The inhibition efficiency increases with the increase of inhibitor concentration and reached 94 at 10–3M for the bipyrazoles studied. Potentiodynamic polarisation studies clearly reveal that the presence of the bipyrazoles does not change the mechanism of the hydrogen evolution reaction and they act essentially as cathodic inhibitors. The effect of temperature on the corrosion behaviour of mild steel in 1M HCl without and with the bipyrazoles at 10–3M was studied in the temperature range from 298° to 343°K. EIS measurements show the increase of the transfer resistance with the inhibitor concentration.

Details

Anti-Corrosion Methods and Materials, vol. 49 no. 3
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 August 2005

M. Bouklah, B. Hammouti, M. Benkaddour, A. Attayibat and S. Radi

To study the effect of inhibition of new bipyrazole derivatives on the corrosion of steel in HCl media at various temperatures.

Abstract

Purpose

To study the effect of inhibition of new bipyrazole derivatives on the corrosion of steel in HCl media at various temperatures.

Design/methodology/approach

In this study, novel corrosion inhibitors, namely bipyrazoles were synthesised and tested as corrosion inhibitors for steel in 1 M HCl. The degree of corrosion was measured using various techniques including weight loss measurements, potentiodynamic polarisation, linear polarisation resistance (Rp) and impedance spectroscopy (EIS).

Findings

It was found that 1,5,5′‐trimethyl‐1H,2′H‐3,3′‐bipyrazole (P1) gave the best inhibition effect. The inhibition efficiency increased with the concentration of P1 to attain 79 per cent at 10−3 M. Good agreement between the various methods explored was observed. Polarisation measurements also showed that P1 acted essentially as a cathodic inhibitor. The cathodic curves indicated that the reduction of proton at the steel surface was an activating mechanism. P1 adsorbed on the steel surface according to Frumkin adsorption model.

Research limitations/implications

The synthesis route offers the possibility of other pyrazolic compounds to be tested in the future.

Practical implications

The inhibitory efficiency of P1 increased with the increase of both the concentration and the temperature (in the 298‐353 K range). As such, P1 can be used in chemical cleaning and pickling processes.

Originality/value

The originality of this work is the synthesis of new inhibitors based on pyrazolic organic compounds.

Details

Pigment & Resin Technology, vol. 34 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 21 May 2020

Parisa Maroufkhani, Wan Khairuzzaman Wan Ismail and Morteza Ghobakhloo

Big data analytics (BDA) is recognized as a turning point for firms to improve their performance. Although small- and medium-sized enterprises (SMEs) are crucial for every…

Abstract

Purpose

Big data analytics (BDA) is recognized as a turning point for firms to improve their performance. Although small- and medium-sized enterprises (SMEs) are crucial for every economy, they are lagging far behind in the usage of BDA. This study aims to provide a single and unified model for the adoption of BDA among SMEs with the integration of the technology–organization–environment (TOE) model and resource-based view.

Design/methodology/approach

A survey of 112 manufacturing SMEs in Iran was conducted, and the data were analysed using structural equation modelling to test the model of this study.

Findings

The results offer evidence of a BDA mediation effect in the relationship between technological, organizational and environmental contexts, and SMEs performance. The findings also demonstrated that technological and organizational elements are the more significant determinants of BDA adoption in the context of SMEs. In addition, the result of this study confirmed that BDA adoption could enhance the financial and market performance of SMEs.

Practical implications

Providing a single unified framework of BDA adoption for SMEs enables them to appreciate the importance of most influential elements (technology, organization and environment) in the adoption of BDA. Also, this study may encourage SMEs to be more willing to use BDA in their businesses.

Originality/value

Although there are studies on BDA adoption and firm performance among large companies, there is a lack of empirical research on SMEs, in particular, based on the TOE model. SMEs differ from large companies in terms of the availability of resources and size. Therefore, this study aimed to initiate a conceptual framework of BDA adoption for SMEs to assist them to be able to take advantage of the adoption of such technology.

Details

Journal of Science and Technology Policy Management, vol. 11 no. 4
Type: Research Article
ISSN: 2053-4620

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Article
Publication date: 19 August 2019

P. Satyabama, Susai Rajendran and Tuan Anh Nguyen

This paper aims to evaluate the inhibition efficiency (IE) of oxalate ions in controlling corrosion of aluminum at pH 10.

Abstract

Purpose

This paper aims to evaluate the inhibition efficiency (IE) of oxalate ions in controlling corrosion of aluminum at pH 10.

Design/methodology/approach

The IE has been determined by the classical weight loss method. The corrosion behavior of aluminum was investigated by using potentiodynamic polarization and electrochemical impedance measurements. Ultra violet (UV)-visible and Fluorescence spectra have been used to analyze the film formed on the aluminum surface after immersion.

Findings

The maximum IE was 88 per cent, which was offered by a mixture of 250 ppm oxalate ions and 50 ppm [Zn2+]. Potentiodynamic polarization data revealed that the protective film was formed on the metal surface. UV-visible and Fluorescence spectra indicated the presence of Al3+−oxalate complex in the protective film formed on aluminum substrate after immersion in [OX]/[Zn2+] solution.

Originality/value

The findings of this work shed more light on the corrosion inhibition of aluminum by oxalate self-assembling monolayers.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 January 2016

Basak Dogru Mert, Mehmet Erman Mert, Gülfeza Kardas and Birgül Yazici

The purpose of this paper is to investigate the adsorption and corrosion inhibition of two isomeric compounds (C4H5N3) as aminopyrazine (AP) and 2-amino-pyrimidine (2AP…

Abstract

Purpose

The purpose of this paper is to investigate the adsorption and corrosion inhibition of two isomeric compounds (C4H5N3) as aminopyrazine (AP) and 2-amino-pyrimidine (2AP) on mild steel (MS) in 0.5 M HCl. The study was a trial to combine experimental and modelling studies and research effect of molecular geometry on inhibition effect of inhibitor molecules.

Design/methodology/approach

The thermodynamic, kinetic and quantum parameters were determined. The electrochemical impedance spectroscopy and anodic polarisation measurements were obtained. The scanning electron microscope was used for monitoring electrode surface. The highest occupied molecular orbital, energy of the lowest unoccupied molecular orbital, Mulliken and natural bonding orbital charges on the backbone atoms, absolute electronegativity, absolute hardness were calculated by density functional theory (DFT)/B3LYP/6-311G (++ d,p).

Findings

Results showed that AP and 2AP suppressed the corrosion rate of MS. The corrosion current values were 0.530, 0.050 and 0.016 mA cm-2 in HCl, AP and 2AP containing HCl solutions, respectively. It was illustrated with the blocked fraction of the MS surface by adsorption of inhibitors which obeyed the Langmuir isotherm. The inhibition efficiency follows the order: 2AP > AP which is in agreement with experimental and quantum results.

Originality/value

This paper provides lay a bridge on the molecular geometry and inhibition efficiency by electrochemical tests and modelling study. The inhibition effect of AP and 2AP has not been compared with each other, neither experimentally nor theoretically. This study put forward possible application of 2AP as corrosion inhibitor especially for closed-circuit systems.

Details

Anti-Corrosion Methods and Materials, vol. 63 no. 5
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 22 May 2020

Sunil Nandankar and Amit Sachan

Despite the substantial research in the domain of electronic procurement adoption, usage and performance (EP AUP), there is no structured review of these studies and most…

Abstract

Purpose

Despite the substantial research in the domain of electronic procurement adoption, usage and performance (EP AUP), there is no structured review of these studies and most of the literature is in fragmented form. Therefore, the purpose of this paper is to investigate and synthesize EP AUP research in the past two decades and map key research approaches, prevailing theories and antecedents used by researchers to study EP AUP at the individual user and organizational level.

Design/methodology/approach

To evaluate and comprehend past and current patterns/themes in the EP AUP research area, a systematic literature review is undertaken. Significant peer-reviewed studies covering three categories – adoption, usage and performance and seven classification criteria are critically reviewed.

Findings

The findings reveal that most investigators mainly used “technology acceptance model,” “technology–organization–environment” framework and their extensions, demonstrating that “perceived ease of use,” “perceived usefulness,” “trust,” “organizational size,” “organizational readiness” and “behavioral intentions” are the most critical drivers of EP AUP.

Research limitations/implications

For researchers and practitioners, the review highlights a taxonomy of contextual factors to be considered for successful EP AUP. It further makes suggestions for future research meeting challenges of Industry-4.0.

Originality/value

To the best of the authors’ knowledge, this is the first systematic literature review undertaken in the field of EP that studies it from three different perspectives. It further builds on the determinants of EP AUP and classifies them in four distinct categories: organizational, individual, information system level and environmental.

Details

Journal of Science and Technology Policy Management, vol. 11 no. 4
Type: Research Article
ISSN: 2053-4620

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Book part
Publication date: 6 September 2018

Wonlop Buachoom

As there is inclusive evidence on relationship between board characteristics and firm performance in the Thai context, and mixed findings of this relationship are usually…

Abstract

As there is inclusive evidence on relationship between board characteristics and firm performance in the Thai context, and mixed findings of this relationship are usually reported from previous studies, this study tries to clarify a reason for the mixed finding by determining the impact of board structures on different quantile levels of firm performance. Building on extant literature and using a developed econometric technique, the Quantile Analysis, on a sample of 446 listed firms in Thailand for a 15-year period ranging from 2000 to 2014, empirical evidence is provided which is consistent with prior studies that some characteristics of the board as the core mechanisms of corporate governance, i.e., board independence, board size, board meeting frequency, and dual role leadership on board, have significant influence on performance of Thai firms. In particular, when considering different quantile levels of firm performance, board structures are found to have different effects across quantile of performance distribution. Board independence and dual role leadership on board are found to have a significant influence on only moderate-performing firms, while board size and board meeting frequency are revealed as having significant impact on only firms with high-performance which need more effectiveness of the board in overseeing and supervising decision-making of the executives. Thus, these findings indicate that considering different quantile levels of firm performance for the board structures and performance relationship should be a reason of previous mixed findings. Moreover, the findings should be important information in encouraging better understanding an optimal governance system in Thailand for related stakeholders such as policymakers, corporate firms, and investors.

Details

Advances in Pacific Basin Business, Economics and Finance
Type: Book
ISBN: 978-1-78756-446-6

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Article
Publication date: 4 October 2019

Klaus North, Nekane Aramburu and Oswaldo Jose Lorenzo

The purpose of this paper is to provide guidance to SMEs to sense and seize digitally enabled growth opportunities as well as start a project-based learning process to…

Abstract

Purpose

The purpose of this paper is to provide guidance to SMEs to sense and seize digitally enabled growth opportunities as well as start a project-based learning process to transform the organization in order to remain competitive in turbulent environments.

Design/methodology/approach

The proposed framework is nurtured from a dynamic capabilities approach as well as from digital transformation studies and mitigates shortcomings of existing frameworks on IT-enabled business transformation. A pilot study has also been carried out for testing the proposed framework.

Findings

The results of the pilot study show that the framework is well understood by SME owners or managers and contributes to a comprehensive perception of digitalization challenges and potentials. The overall maturity level of the 52 companies analyzed is moderate. Firms are better at “sensing” than “seizing”, that is, at identifying digitally based growth opportunities than in profiting from them. The test of the proposed framework also contributes to its further adjustment and refinement.

Practical implications

The developed framework is useful for owners and managers of SMEs as a self-assessment of digital maturity. It sets a baseline regarding the current position and supports coordinated initiatives for digitally enabled growth.

Originality/value

Few frameworks regarding digital maturity have been developed. Most of them lack a sound theoretical foundation and are less suited to the needs of SMEs. There are few studies on digitalization in SMEs and they are not focussed on capabilities development but mostly on processes (Trung Pham 2010; Blatz et al., 2018; Mittal et al., 2018). Therefore, the originality of this paper is to propose a framework that allows SMEs to assess their digital maturity level and the capabilities associated with each level to enhance digitally enabled growth, contributing to expand the research on the relationship between dynamic capabilities and digitalization (Teece, 2017).

Details

Journal of Enterprise Information Management, vol. 33 no. 1
Type: Research Article
ISSN: 1741-0398

Keywords

1 – 10 of 201