L. Dzib‐Pérez, J. González‐Sánchez, J.M. Malo and F.J. Rodríguez
The aim of this paper is to study and analyse the advantages and limitations of the scanning reference electrode technique (SRET) to detect and assess localised electrochemical…
Abstract
Purpose
The aim of this paper is to study and analyse the advantages and limitations of the scanning reference electrode technique (SRET) to detect and assess localised electrochemical activity based on an evaluation of the influence of the principal test parameters on the sensitivity and resolution of the technique.
Design/methodology/approach
Measurements of Ohmic potential gradients induced by ionic flux close to a point current source (PCS) were carried out using a scanning reference electrode technique (SRET) instrument, which comprised a vertical rotating working electrode and a scanning probe formed by a pair of platinum electrodes of approximately 200 μm of diameter. Ionic flux was induced by anodic polarisation applied to a gold micro‐disc electrode, which acted as the PCS. Measurements were conducted in electrolytes of ten different conductivities, using different scanning probe tips to sample surface distance and different working electrode rotation rates. The range of conductivities used included most of the possible electrolytes to which metallic materials can be in contact under real service conditions.
Findings
The SRET signal sensed from a polarised PCS showed a strong dependence on the rotation rate of the working electrode for electrolytes of low conductivity but a minimal effect on electrolytes with conductivities higher than 50 mS/cm.
Originality/value
This work presents the effect of wide variations on the electrochemical and operational conditions on the sensitivity and resolution of SRET signal response and discusses the limitations of the technique to assess localised electrochemical activity due to the effect of high conductivity electrolytes, large separation distance between the SRET scanning probe and developing dissolution and scanning rate of a the localised site.
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Fernando García‐Hernandez, Luis Hernández‐Sandoval, Carlos Regalado‐González, José Mojica‐Gómez, Yunny Meas‐Vong, Guillermo Espinosa‐Acosta, Miriam Estévez and Victor Castaño
The purpose of this paper is to study the corrosion of carbon steel without coating and when protected using three different hybrid coatings, i.e. a bi‐component polyurethane with…
Abstract
Purpose
The purpose of this paper is to study the corrosion of carbon steel without coating and when protected using three different hybrid coatings, i.e. a bi‐component polyurethane with nano‐particles of SiO2 with and without sacrificial anode particles, and a mono‐component polyurethane with SiO2 particles.
Design/methodology/approach
In this investigation three different nano‐structured coatings are developed and applied to steel substrates and then tested for their corrosion resistance (defined as “Rn”), under a very aggressive medium (pH=1.5) in a dynamic system (loop reactor). Their performance is evaluated using an electrochemical noise (EN) resistance technique. The electrodes are connected to a potentiostat and measurements are recorded as per the EN technique over a 2,048 s duration at 0, 24, and 48 h intervals. Scanning electron microscopy (SEM) are obtained before and after the corrosion trials to characterize the control and the different coating systems.
Findings
The results show that a bicomponent coating, made up of alkyd resin and silica nanoparticles demonstrated the best performance, whereas the coating formed by SiO2 nanoparticles and polyurethane resin showed relatively low corrosion resistance. The inclusion of zinc nanoparticles in a third coating as sacrificial nano‐anodes led to segregation and resulted in moderate corrosion resistance. These results are confirmed by SEM observations.
Originality/value
The results obtained in this paper provide an insight to the understanding of the anticorrosion properties of three different hybrid coatings in a dynamic system (loop reactor).
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V. Torres‐Mendoza, F.J. Rodríguez‐Gómez, E.M. García‐Ochoa and J. Genesca
The aim of this work is to evaluate the electrochemical noise (EN) method as a way of evaluating quickly the aggressiveness of natural atmospheres.
Abstract
Purpose
The aim of this work is to evaluate the electrochemical noise (EN) method as a way of evaluating quickly the aggressiveness of natural atmospheres.
Design/methodology/approach
Wire‐on‐bolt tests were used, which implies an exposure of at least three months of bimetallic specimens such as aluminium wire/steel bolt and aluminium wire/copper bolt (CLIMAT units). Electrochemical noise measurements (ENM) also were used.
Findings
EN is a powerful tool in the assessing of aggressiveness of atmospheres in short time exposure. Statistical analyses of EN were carried out and provided clear differences between atmospheres depending on pollutants. Results of noise resistance (Rn), root mean square of current (Irms) and localization index are discussed.
Research limitations/implications
The possible application of ENM to atmospheric corrosion is interesting from a practical point of view. However, more experiments are necessary in order to test a wide range of atmospheres.
Practical implications
EN has proved to be a useful tool when localised corrosion is detected and the presence of chlorides in atmospheres, due to sea fog, results in pitting on the metallic samples.
Originality/value
Illustrates that electrochemical noise can be a powerful tool for assessing the aggressiveness of natural atmospheres.
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Aynaz Lotfata and Shrinidhi Ambinakudige
The elevated level of nitrate in groundwater is a serious problem in Texas aquifers. To control and manage groundwater quality, the characterization of groundwater contamination…
Abstract
Purpose
The elevated level of nitrate in groundwater is a serious problem in Texas aquifers. To control and manage groundwater quality, the characterization of groundwater contamination and identification of the factors affecting the nitrate concentration of groundwater are significant. The purpose of this paper is to determine factors which have significant impacts on the elevated groundwater nitrate concentrations of the Southern High-Plains and the Edwards-Trinity aquifers.
Design/methodology/approach
The characterization of groundwater nitrate contamination was undertaken by analyzing the hydrochemical data of groundwater within a statistical framework. The multivariate statistical analysis (ordinary least square) and geographically weighted regression (GWR) models were used to study the relationship between groundwater nitrate contamination and land use of the study areas.
Findings
Results show groundwater nitrate contamination is typically due to an overapplication of N fertilizers to cotton in the Southern High-Plains aquifer and to grassland in the Edwards-Trinity aquifer. Adjusted R2 (0.45) explains variations of nitrate concentration by well-depth, cotton production, shrubland and grassland in the Edwards-Trinity aquifer. The results of an analysis of variations in N concentration with well depth for all 192 wells indicate that nitrate concentrations in water from wells in the Southern High-Plains and Edwards-Trinity aquifers tend to decrease with increasing well-depth.
Originality/value
In this study, the GWR model was built to identify nitrate concentration within a geographic framework to ensure sustainable use of groundwater, which is important for local management purposes. The analysis should include local spatial variations of elements such as hydrologic characteristics and the land use activities if groundwater nitrate contamination causes adverse effects on human and ecosystem health.
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Suhair Alkilani and Martin Loosemore
This research uses contingency theory and Venkatraman’s concept of moderating fit to explore how key project stakeholders (clients, consultants and suppliers) influence project…
Abstract
Purpose
This research uses contingency theory and Venkatraman’s concept of moderating fit to explore how key project stakeholders (clients, consultants and suppliers) influence project performance from the perspective of small and medium contractors in the Jordanian construction industry.
Design/methodology/approach
An anonymous structured survey was performed comprising 200 key informants including senior project managers, construction managers, engineers and general managers working for small- and medium-sized contractors in the Jordanian construction industry. The Partial Least Squares Structural Equation Modelling (PLS-SEM) was used to analyse the data.
Findings
The results of this study show that consultant-related factors (quality of documentation produced, ability to communicate and technical competencies) are perceived to have the most significant direct effect on project performance, followed by client-related factors (payment promptness, decision certainty and documentation control) and supplier-related factors (supplier performance, defects control and logistics management).
Originality/value
The results contribute new theoretical, empirical and practical insights to existing construction project performance research by highlighting the key performance factors which need to be managed for each stakeholder group to ensure effective project performance from a small- and medium-sized contractor perspective.
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Wesam Beitelmal, Keith R. Molenaar, Amy Javernick-Will and Eugenio Pellicer
The increased need for, and maintenance of, infrastructure creates challenges for all agencies that manage infrastructure assets. To assist with these challenges, agencies…
Abstract
Purpose
The increased need for, and maintenance of, infrastructure creates challenges for all agencies that manage infrastructure assets. To assist with these challenges, agencies implement asset management systems. The purpose of this paper is to investigate and compare the importance of barriers faced by agencies establishing transportation asset management systems in the USA and Libya to contrast a case of a developed and developing country.
Design/methodology/approach
A literature review identified 28 potential barriers for implementing an asset management system. Practitioners who participate in decision-making processes in each country were asked to rate the importance of each barrier in an online survey questionnaire. Descriptive statistics, Kendall Concordance W., and Mann-Whitney are used to analyze the collected data.
Findings
Through an analysis of 61 completed questionnaires, 14 barriers were identified as important by both the US and Libyan practitioners. A total of 11 additional barriers, primarily in the areas of political and regulatory obstacles, were determined to be important only for Libya. These 11 barriers provide reasonable insights into asset management systems’ barriers for developing countries.
Practical implications
The list of barriers identified from this research will assist decision makers to address and overcome these barriers when implementing asset management systems in their specific organizational and country conditions.
Originality/value
The research identified standard barriers to implementing asset management systems and identified barriers that were specific to the country context, such as political and regulatory barriers in Libya. When viewed with the asset management literature, the results show broad applicability of some asset management barriers and the need to contextualize to country context (e.g. developing countries) for other barriers.
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Sang Hoon Han, Kaifeng Jiang and Jaideep Anand
This chapter discusses how the real options theory can be useful for understanding the adoption of human resources management (HRM) practices. The authors review how the real…
Abstract
This chapter discusses how the real options theory can be useful for understanding the adoption of human resources management (HRM) practices. The authors review how the real options theory has provided insights into the processes through which firms manage uncertainties involved in the adoption of HRM practices. The authors offer propositions for future HRM research from the real options perspective. The authors contend that analyzing HRM practice adoptions through the lens of real options theory can enhance our understanding of the mechanisms through which firms choose which HRM practices to adopt and how they adjust the timing, scale, and methods of investment in these practices. Specifically, the authors suggest that differences in information relevant to valuation of HRM options are the source of distinct choices of HRM options across firms. Finally, the authors propose advancing knowledge on HRM practice adoptions by using a portfolio of options approach, as well as considering factors like competitors, path dependence, and switching options.
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Nora Munguía, Andrea Zavala, Amina Marin, Rafael Moure‐Eraso and Luis Velazquez
The purpose of this article is to explore the pollution prevention practices performed by workers in the Mexican auto refinishing industry as well as their implications on the…
Abstract
Purpose
The purpose of this article is to explore the pollution prevention practices performed by workers in the Mexican auto refinishing industry as well as their implications on the occupational, safety and environmental health of workers and community.
Design/methodology/approach
Interviewer‐administered questionnaires were conducted with shop owners, workers, and neighbors, and repeated site visits to collect information on occupational practices (personal protective equipment (PPE) in use, engineering controls, hazard communication, level of technology), environmental impact (chemicals usage, wastes amounts, disposal, supply chain, impact to the neighborhood), and possible symptoms of work‐related adverse health effects.
Findings
The findings indicate that the Mexican auto body shop industry is not consistent with the accepted precepts of sustainability because it is not addressing the underlying topics of health, safety, and environment. When comparing working conditions between auto body workers in developed countries and those in Mexico, it is evident that Mexican workers perform their tasks under critical conditions; therefore, under considerable occupational and environmental risks.
Practical implications
This article reveals five P2 opportunities that seem to have a potential relevance to the development of prevention and intervention strategies in the region to secure long‐term economic growth while improving environmental and working conditions.
Originality/value
This article provides the first insights about several opportunities for adopting pollution prevention strategies that improve environmental and occupational conditions in the auto refinishing industry in developing countries.
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Chhotu Ram, Chhaya Sharma and A K Singh
– This paper aims to report on corrosivity of secondary-stage paper mill effluent and corrosion performance of stainless steels.
Abstract
Purpose
This paper aims to report on corrosivity of secondary-stage paper mill effluent and corrosion performance of stainless steels.
Design/methodology/approach
For this purpose, immersion test and electrochemical polarization tests were conducted in mill and synthetic effluent to evaluate the uniform and localized corrosion.
Findings
Corrosivity of mill effluent has been compared with synthetic and primary-stage effluent of the same mill. It is observed that anions present in them, viz. SO4−, PO34−, NO2− and NO3−, impart inhibition, whereas Cl− and chlorophenols enhance the corrosivity of the effluent. The overall effect of various components was reduction in corrosivity of secondary mill effluent.
Originality/value
These observations can be useful for material selection and helpful in corrosion mitigation in paper mill effluent treatment plants.