M.N. DESAI, V.K. SHAH and M.H. GANDHI
Due to the constituent nitrogen atom of the amino group, amines have been extensively used as inhibitors of metallic corrosion. This article reviews the reported uses of aniline…
Abstract
Due to the constituent nitrogen atom of the amino group, amines have been extensively used as inhibitors of metallic corrosion. This article reviews the reported uses of aniline and related aromatic amines as corrosion inhibitors.
M.N. Desai and Y.C. Shah
α‐naphthylamine, thioglycolic acid and urea have been investigated as inhibitors of the corrosion of 63/37 brass in nitric acid. Thioglycolic acid is the most efficient inhibitor…
Abstract
α‐naphthylamine, thioglycolic acid and urea have been investigated as inhibitors of the corrosion of 63/37 brass in nitric acid. Thioglycolic acid is the most efficient inhibitor which affords nearly complete protection to brass. All the three substances predominantly act on local cathodic areas.
M.N. Desai, G.H. Thanki and D.K. Shah
2: Aminobenzoic acids as inhibitors in nitric acid Ortho, meta and para aminobenzoic acids have been studied as corrosion inhibitors for 60/40 brass in nitric acid. Ortho and para…
Abstract
2: Aminobenzoic acids as inhibitors in nitric acid Ortho, meta and para aminobenzoic acids have been studied as corrosion inhibitors for 60/40 brass in nitric acid. Ortho and para aminobenzoic acids are cathodic in action whereas meta aminobenzoic acid acts by influencing both the cathodic and anodic reactions.
Lacan et. al. studied oleic acid, naphthenic acid, stannous chloride, potassium dihydrogen phosphate and cobalt linolate for the prevention of corrosion of brass in sodium…
Abstract
Lacan et. al. studied oleic acid, naphthenic acid, stannous chloride, potassium dihydrogen phosphate and cobalt linolate for the prevention of corrosion of brass in sodium hydroxide solutions.
J.D. Talati, M.N. Desai and N.K. Shah
The evaluation of Schiff bases derived from o‐, m‐ and p‐aminophenols and salicylaldehyde as corrosion inhibitors of zinc in sulfuric acid and to study their action mechanism.
Abstract
Purpose
The evaluation of Schiff bases derived from o‐, m‐ and p‐aminophenols and salicylaldehyde as corrosion inhibitors of zinc in sulfuric acid and to study their action mechanism.
Design/methodology/approach
The effect of various parameters on the behaviour of these inhibitors has been studied using the weight loss and polarization measurements.
Findings
In general, the ortho isomer was highly effective as a corrosion inhibitor because it formed a chelate with a six‐membered ring and moreover the ortho isomer possessed pronounced electromeric effect. These inhibitors obey the Langmuir adsorption isotherm. The almost constant performance with temperature in the case of ortho and para isomers in 0.5 M sulfuric acid suggested strong adsorption bonds. The thermodynamic parameters suggested that this strong interaction of the inhibitor molecules with the metal surface resulted in spontaneous adsorption. It may be concluded that a good inhibitor is characterised by a relatively greater decrease in free energy of adsorption, lower entropy of adsorption and higher heat of adsorption. Polarization data indicated that all these isomers were predominantly cathodic inhibitors. The conjoint effect of external cathodic current and these inhibitors was either synergistic or additive.
Research limitations/implications
Even more powerful Schiff bases need to be synthesised and evaluated as corrosion inhibitors with a number of metals and alloys in diverse media, which may be effective at low concentrations.
Originality/value
Very few inhibitors exhibit such excellent inhibitive effect on zinc in aggressive corrosive media. Rarely do we find such detailed studies.
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M.N. Desai, J.D. Talati and N.K. Shah
A survey of technical literature indicates that there is a shortage of excellent corrosion inhibitors for zinc in non‐oxidizing acids, particularly sulphuric acid. This paper aims…
Abstract
Purpose
A survey of technical literature indicates that there is a shortage of excellent corrosion inhibitors for zinc in non‐oxidizing acids, particularly sulphuric acid. This paper aims to describe the behaviour of ethylenediamine‐N‐N′‐dibenzylidene, ethylenediamine‐N‐N′‐disalicylidene, ethylenediamine‐N‐N′‐dicinnamylidene, triethylenetetramine tribenzylidene and triethylenetetramine trisalicylidene as corrosion inhibitors for zinc in sulphuric acid solutions. The objective of this research work also is to have an insight into the action mechanism of these inhibitors.
Design/methodology/approach
The effect of the various parameters affecting the action of the above‐mentioned corrosion inhibitors has been studied using weight‐loss data and polarisation measurements. Adsorption data also were utilized.
Findings
The inhibitors showed excellent corrosion inhibition (>99 per cent) at effective inhibitor concentrations. The two salicylidenes were better corrosion inhibitors than were corresponding benzylidenes. It appeared from this study that an efficient inhibitor is characterised by a relatively greater decrease in free energy of adsorption, lower entropy of adsorption and relatively lower heat of adsorption. Basically, these inhibitors were cathodic, as was revealed by polarisation data, and the inhibitors followed Langmuir adsorption isotherm behaviour. In general, the conjoint action of the inhibitor and the cathodic current was synergistic.
Research limitations/implications
Powerful Schiff bases still need to be synthesized so as to be effective at extremely low concentrations. The behaviour with other metals and alloys in diverse media also requires to be investigated.
Originality/value
Very few inhibitors demonstrate such excellent corrosion inhibition of zinc in aggressive corrosive media. Such detailed investigations on corrosion inhibitors are unusual.
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Valmiane Vieira Azevedo Almeida, Carlos Francisco Simões Gomes, Luis Hernan Contreras Pinochet and Marcos dos Santos
This paper aims to comprehensively analyze renewable energy alternatives in Brazil, focusing on identifying the most suitable option for investment in the country’s sustainable…
Abstract
Purpose
This paper aims to comprehensively analyze renewable energy alternatives in Brazil, focusing on identifying the most suitable option for investment in the country’s sustainable development.
Design/methodology/approach
The study adopts the step-wise weight assessment ratio analysis-multiobjective optimization by ratio analysis −3NAG (a combination of three normalization methods) methodology, a multicriteria decision-making approach, to evaluate and rank renewable energy sources based on key criteria such as resource availability, cost-effectiveness, job creation potential and environmental impact.
Findings
The analysis reveals that solar energy emerges as the preferred choice for Brazil, offering significant advantages over other alternatives such as hydroelectric, wind and biomass energy. Solar energy’s distributed generation capability, cost reduction trends and positive environmental impact contribute to its favorable position in meeting Brazil’s energy needs.
Research limitations/implications
While the study provides valuable insights into renewable energy selection, there are limitations regarding the criteria’ scope and the exclusion of specific renewable energy options. Future research could explore sensitivity analyses and incorporate additional criteria to enhance the study’s comprehensiveness.
Originality/value
This research contributes to the existing literature by thoroughly analyzing renewable energy alternatives in Brazil using a robust multicriteria decision-making methodology. The study’s findings provide actionable guidance for policymakers, businesses and stakeholders seeking to promote sustainable energy development in the country.
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People face barriers and failures in various kinds of information seeking experiences. These are often attributed to either the information seeker or the system/service they use…
Abstract
Purpose
People face barriers and failures in various kinds of information seeking experiences. These are often attributed to either the information seeker or the system/service they use. The purpose of this paper is to investigate how and why individuals fail to fulfill their information needs in all contexts and situations. It addresses the limitations of existing studies in examining the context of the task and information seeker’s strategy and seeks to gain a holistic understanding of information seeking barriers and failures.
Design/methodology/approach
The primary method used for this investigation is a qualitative survey, in which 63 participants provided 208 real life examples of failures in information seeking. After analyzing the survey data, ten semi-structured interviews with another group of participants were conducted to further examine the survey findings. Data were analyzed using various theoretical frameworks of tasks, strategies, and barriers.
Findings
A careful examination of aspects of tasks, barriers, and strategies identified from the examples revealed that a wide range of external and internal factors caused people’s failures. These factors were also caused or affected by multiple aspects of information seekers’ tasks and strategies. People’s information needs were often too contextual and specific to be fulfilled by the information retrieved. Other barriers, such as time constraint and institutional restrictions, also intensified the problem.
Originality/value
This paper highlights the importance of considering the information seeking episodes in which individuals fail to fulfill their needs in a holistic approach by analyzing their tasks, information needs, strategies, and obstacles. The modified theoretical frameworks and the coding methods used could also be instrumental for future research.
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Mrs. D.K. Padma and T.L. Rama Char
Thiourea and nicotinic acid are good inhibitors for the corrosion of brass in nitric acid solutions. Polarisation studies indicate that the anode polarisation with nicotinic acid…
Abstract
Thiourea and nicotinic acid are good inhibitors for the corrosion of brass in nitric acid solutions. Polarisation studies indicate that the anode polarisation with nicotinic acid is less than that on the cathode side. Both the inhibitors increase the cathode and anode polarisation considerably.
This conceptual paper aims to demonstrate a holistic, multifaceted framework of interest development, information search, and knowledge construction (ISK) on children’s diverse…
Abstract
Purpose
This conceptual paper aims to demonstrate a holistic, multifaceted framework of interest development, information search, and knowledge construction (ISK) on children’s diverse information search behaviors.
Design/methodology/approach
By reviewing previous literature on children’s interest development, online information seeking and search, and knowledge construction, we propose the ISK framework. Then, we provide example case studies with pilot analyses using qualitative approaches (e.g. video-based interaction analysis, thematic analysis) showing how the framework can be applied to different types of authentic information-seeking situations for children.
Findings
The ISK framework demonstrates the multifaceted interplays between children’s information behavior and their cognitive and affective development. This framework was supported using previous studies and pilot empirical applications. We also included potential research questions that could be addressed using the framework.
Originality/value
Our paper provides a conceptual grounding to an in-depth, multidimensional understanding of children’s information behavior, which have been limitedly addressed in previous studies. Considering that children begin to search from their early stage of development and their search behaviors are tightly associated with other developmental states, our paper highlights the importance of investigating children’s search and information seeking and provides theoretical and empirical implications.