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Article
Publication date: 1 October 1997

M.M. Osman and M.N. Shalaby

The inhibition effect of some non‐ionic surfactants Tween 20, Tween 40, Tween 60, Tween 80 and O1 (EO)20 on steel in acidic chloride solution has been investigated by studying…

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Abstract

The inhibition effect of some non‐ionic surfactants Tween 20, Tween 40, Tween 60, Tween 80 and O1 (EO)20 on steel in acidic chloride solution has been investigated by studying their adsorption behaviour and the use of the gravimetric method in order to determine the inhibition efficiency. The results obtained show that these compounds are very good inhibitors. High inhibition efficiency is observed around their critical micelle concentrations (CMC), and it increases with the number of carbon atoms in the chain length of their molecules.

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Anti-Corrosion Methods and Materials, vol. 44 no. 5
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 October 2001

M.N. Shalaby and M.M. Osman

Sodium oleic sulfonate (SOS), polyoxyethylene (20) sorbitan monooleate (Tween 80 or T80) and their mixtures have been studied as acid corrosion inhibitors for mild steel in 1M HCl…

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Abstract

Sodium oleic sulfonate (SOS), polyoxyethylene (20) sorbitan monooleate (Tween 80 or T80) and their mixtures have been studied as acid corrosion inhibitors for mild steel in 1M HCl using adsorption and gravimetric techniques. All the data reveal that the compounds act as inhibitors in the acid environment. The adsorption and inhibition efficiency are discussed as a function of the concentration and the nature of mixing the two surfactants. T80 + αSOS mixtures show a better inhibition effect than SOS + αT80, that increases with the value of αSOS. The interaction and synergism of the investigated mixtures are studied by calculating the interaction parameters (β) and the degree of synergism (S) from surface tension‐concentration and corrosion data. The degree of synergism for T80 + αSOS is higher than that of SOS + αT80. This is believed to be due to the presence of the small amount of the co‐surfactant SOS which serves as an anchor molecule for the nonionic molecules.

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Anti-Corrosion Methods and Materials, vol. 48 no. 5
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 August 1999

M.N. Shalaby, M.M. Osman and A.A. El Feky

Corrosion inhibition of carbon steel by nonionic polyoxy ethylene (80) monopalmitate (Pa (EO)80), cationic hexadecyltrimethylammonium bromide (HTABr) and anionic sodium dodecyl…

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Abstract

Corrosion inhibition of carbon steel by nonionic polyoxy ethylene (80) monopalmitate (Pa (EO)80), cationic hexadecyltrimethylammonium bromide (HTABr) and anionic sodium dodecyl sulfate (SDS) in sea water has been evaluated by weight loss method, correlated with adsorption measurements and X‐ray analysis. The inhibition efficiency of these compounds increases with their concentration and reaches a maximum value around their critical micelle concentrations (CMCs). The adsorption isotherms of the tested samples exhibit an L‐shape and the experimental data fit the Langmuir adsorption isotherm. The maximum amount adsorbed at the pseudo‐plateau region (Gmax) calculated from the Langmuir equation increases in the order SDS < HTABr < Pa (EO)80. The X‐ray spectra showed that the steel surfaces inhibited with these compounds were covered with lepidocrocite (FeOOH). The crystallite size is influenced by the type of the surfactant following their inhibition efficiency in the same order.

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Anti-Corrosion Methods and Materials, vol. 46 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 October 2001

P. Manjula, S. Manonmani, P. Jayaram and S. Rajendran

The inhibition efficiency of N‐cetyl‐N,N,N‐trimethylammonium bromide (CTAB), a cationic surfactant, in controlling the corrosion of carbon steel in an aqueous solution containing…

420

Abstract

The inhibition efficiency of N‐cetyl‐N,N,N‐trimethylammonium bromide (CTAB), a cationic surfactant, in controlling the corrosion of carbon steel in an aqueous solution containing 60ppm Cl, in the absence and presence of Zn2+ and also calcium gluconate (CG), had been evaluated by the weight‐loss method. Weight‐loss studies revealed that the behaviour of CTAB changed when its concentration is ≥ 150ppm. Organisation of assembly of CTAB molecules is expected to take place at this critical concentration. The protective film has been analysed using FTIR spectra. In the presence of CTAB, the protective film consists of Fe2+‐CTAB complex. In the presence of CTAB and Zn2+, the protective film consists of Fe2+‐CTAB complex and Zn(OH)2. In the presence of CTAB and calcium gluconate, the protective film consists of Fe2+‐CTAB complex, Fe2+‐gluconate complex and Ca(OH)2.

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Anti-Corrosion Methods and Materials, vol. 48 no. 5
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 February 2000

S. Rajendran, B.V. Apparao and N. Palaniswamy

The influence of a cationic surfactant, N‐cetyl‐N, N, N‐trimethyl ammonium bromide (CTAB) on the inhibition efficiency (IE) of calcium gluconate (CG) – Zn2+ system in controlling…

387

Abstract

The influence of a cationic surfactant, N‐cetyl‐N, N, N‐trimethyl ammonium bromide (CTAB) on the inhibition efficiency (IE) of calcium gluconate (CG) – Zn2+ system in controlling corrosion of mild steel in a neutral aqueous environment containing 60ppm Cl has been evaluated by weight‐loss method. The formulation consisting of 200 ppm CG and 50ppm Zn2+ has 86 per cent IE (immersion period = three days). Addition of various concentrations of CTAB to the above system improves the IE to 99 per cent. Presence of CTAB facilitates the transport of CG and Zn2+ from the bulk of the solution to the metal surface. The nature of the protective film formed on the surface of mild steel has been analysed by FTIR and fluorescence spectra. The protective film is found to be fluorescent and to consist of iron‐CG complex, iron‐CTAB complex and Zn(OH)2.

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Anti-Corrosion Methods and Materials, vol. 47 no. 1
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 23 October 2021

M.M. Elsawy, Mohamed A. Awad, Nashwa M. Saleh and H. Abd El-Wahab

Paper aims to Preparation and evaluation of isoxazole benzene sulfonamide derivatives and incorporated it with waterborne household paints to develop coating compositions as an…

162

Abstract

Purpose

Paper aims to Preparation and evaluation of isoxazole benzene sulfonamide derivatives and incorporated it with waterborne household paints to develop coating compositions as an insecticidal coating against Musca domestica adults.

Design/methodology/approach

The synthesized compounds were prepared and confirmed by different analyzes, fourier transform infra-red (FTIR), mass, proton nuclear magnetic resonance (1HNMR) and Carbon 13 nuclear magnetic resonance (13CNMR) spectra. The prepared compound has been blended with waterborne household paint formulation, the physical and mechanical properties of the paint formulation has been studied. The efficiency of the isoxazole benzene sulfonamide derivatives when incorporated with waterborne paint against Culex quinquefasciatus and Mosquito house fly adults, also have been examined.

Findings

The obtained results of the paint formulations confirmed their best performance and providing good scrub resistance. Also, the finding promising results of the insecticide test of the paint formulation may be because of the biological activity of these compounds and containing sulfonamide, cyanide and free aromatic amine groups comparing with the standard recommended organophosphorus insecticide. The order activity increase with increasing the dose concentration of the isoxazole derivatives and the activity of chemical compounds itself is represented in terms of their medium lethal concentrations LC50 (LC90), which recorded 0.90(1.62), 0.89(1.61) and 0.86(1.56) g/ml for 5, 3 and 4 chemical compounds, respectively, after 72 h from treatment.

Practical implications

These types of organic compounds are friendly environmentally and can be used as a biocide with different types of paint formulations.

Originality/value

Insecticide waterborne household paints based on isoxazole benzene sulfonamide derivatives as insecticide agents are novel.

Details

Pigment & Resin Technology, vol. 51 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 January 2006

Dong Youp Ryu and Michael L. Free

To evaluate mild steel corrosion using a new surfactant‐inhibition model which was derived, in part, from the concept of intermolecular energy and molecular separation distance.

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Abstract

Purpose

To evaluate mild steel corrosion using a new surfactant‐inhibition model which was derived, in part, from the concept of intermolecular energy and molecular separation distance.

Design/methodology/approach

A Gamry potentiostat was used for polarization resistance tests to determine corrosion rate and the level of adsorption of surfactant at the solution‐metal interface was determined using UV‐spectroscopy. The relationship between inhibition and surfactant adsorption as well as metal corrosion was investigated using a traditional surfactant‐inhibition model, which assumes inhibition is directly proportional to surfactant coverage and new model.

Findings

The comparison of adsorption data and corrosion inhibition data shows inhibition was not directly proportional to physical coverage as assumed by the traditional inhibition model. Instead, it was found that coverage was related to inhibition through a power‐law dependency that is similar to that used to determine molecular interaction energies.

Research limitations/implications

The new model was evaluated only for dodecyl pyridinium chloride mild steel system. The evaluation of the new model for various surfactant‐metal systems is suggested for future research.

Originality/value

The new model was found to more accurately predict the relationship between inhibition and coverage rather than traditional models for dodecyl pyridinium chloride‐mild steel system.

Details

Anti-Corrosion Methods and Materials, vol. 53 no. 1
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 8 May 2017

Manish Kumar Chatli, Neeraj Gandhi and Parminder Singh

The sensory quality and yield of mozzarella cheese deteriorate as the fat content in milk is reduced. This study aims to evaluate the efficacy of sodium alginate as a fat replacer…

278

Abstract

Purpose

The sensory quality and yield of mozzarella cheese deteriorate as the fat content in milk is reduced. This study aims to evaluate the efficacy of sodium alginate as a fat replacer in low-fat buffalo mozzarella cheese on the basis of processing and storage (4 ± 1°C) quality.

Design/methodology/approach

Five treatments of buffalo mozzarella cheese, viz., control full-fat cheese (6.0 per cent milk fat; CFFC), control low-fat cheese (<0.5 per cent milk fat) without sodium alginate (CLFC), low-fat cheese with 0.1 per cent sodium alginate (LFC-1), 0.2 per cent sodium alginate (LFC-2) and 0.3 per cent sodium alginate (LFC-3), were comparatively evaluated.

Findings

Increase in the level of sodium alginate increased the percent yield of treated low-fat cheese than CLFC. Addition of sodium alginate to low-fat cheese resulted in decrease in hardness (p = 0.023) and chewiness than CLFC. Meltability was significantly decreased (p = 0.03) in low-fat cheese than CFFC. It was recorded as 1.5 ± 0.14 cm for CFFC to 0.2 ± 0.08 cm in LFC-3. Sensory panellists awarded LFC-3 highest and lowest to LFC-1; however, treated products at all selected levels were superior to CLFC. Oxidative stability and microbial stability were improved in LFC-3 than CFFC during storage.

Practical implications

Results concluded that 0.3 per cent sodium alginate is optimum for the development of extended shelf-life functional/low-fat/low-calorie buffalo mozzarella cheese.

Originality/value

Processing interventions can be successfully used to develop low-fat/low-calorie mozzarella cheese with acceptable sensory attributes and longer storage life.

Details

Nutrition & Food Science, vol. 47 no. 3
Type: Research Article
ISSN: 0034-6659

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Article
Publication date: 13 May 2024

Christina Zacharia Hawatmeh, Iman Abu Hashish and Rawand Rami Alazzeh

This article aims to illuminate the gendered organisational structure of higher education in Jordan by collecting and analysing a national-level snapshot of the current…

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Abstract

Purpose

This article aims to illuminate the gendered organisational structure of higher education in Jordan by collecting and analysing a national-level snapshot of the current distribution of women and men in leadership positions and academic ranks across Jordanian universities to pinpoint inequalities in specific levels and fields.

Design/methodology/approach

Grounded in gendered organisational theory, this study presents a snapshot of the gender composition of 10 public and 14 private universities in Jordan. The snapshot, collected in September 2022 from these universities’ websites, examines counts of male and female administrative leaders as well as academic staff across all ranks for all faculties in both STEM and liberal arts fields.

Findings

The distribution of women and men in leadership positions in universities across Jordan is highly unequal, with men outnumbering women in the uppermost positions by nearly 10:1. This gap decreases as the rank of positions decreases, indicative of a highly gendered organisational structure, with only three to four fields approaching gender parity.

Research limitations/implications

This paper offers a comprehensive and detailed quantitative foundation for researchers to investigate the underlying social, cultural, legal, political and economic factors perpetuating gender inequality in academia in Jordan and in comparative studies.

Practical implications

This study is relevant for targeting policies for advancing sustainable development goals, specifically 5.5, which aim at women’s full and effective participation and equal opportunities for leadership at all levels of decision-making.

Originality/value

This study provides the most detailed and extensive macro-level analysis of the gender composition of universities in Jordan.

Details

International Journal of Organizational Analysis, vol. 33 no. 2
Type: Research Article
ISSN: 1934-8835

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Article
Publication date: 26 July 2024

Bolanle Oyindamola Adebayo and Hannah M. Sunderman

To maximize the benefits of intercultural mentoring relationships, which are increasing in today’s diverse higher education environment, the current article conceptualizes the…

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Abstract

Purpose

To maximize the benefits of intercultural mentoring relationships, which are increasing in today’s diverse higher education environment, the current article conceptualizes the connection between intercultural mentoring and cultural competence among mentors and mentees as a learning process.

Design/methodology/approach

The conceptual paper discusses the nuanced aspects of intercultural mentoring. Ultimately, the current article presents a framework for a bidirectional relationship between intercultural mentoring and cultural competence through experiential learning theory and intergroup contact theory, resulting in implications for practitioners and actionable research directions.

Findings

The article highlights the interplay and interdependence of cultural competence and intercultural mentoring through experiential learning and intergroup contact theory. Cultural competence influences the quality of intercultural mentoring relationships. Conversely, intercultural mentoring relationships can develop cultural competence in mentors and mentees through experiential learning, producing positive intergroup contact behaviors. Findings suggest the need for active learning and unlearning among mentors and mentees in intercultural mentoring relationships to maximize developmental outcomes (e.g. cultural competence).

Originality/value

The proposed framework emphasizes that (1) the possession of cultural competence is a critical success factor for intercultural mentoring relationships, (2) the development of cultural competence is an outcome of successful intercultural mentoring relationships, and (3) intercultural mentoring relationships should be regarded as experiential learning platforms that can produce positive intercultural traits such as cultural competence.

Details

International Journal of Mentoring and Coaching in Education, vol. 14 no. 1
Type: Research Article
ISSN: 2046-6854

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