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The effect of different cooling methods on the corrosion behaviour at welded area of aluminium alloy 5083 was investigated by using weight loss study, potendynamic polarization study and morphology study. All samples were cooled by using air cooling method and quenching method. There was an increase of weight loss for both cooling methods where samples with air cooling method showed lower percentage of weight loss as compared to samples with quenching methods. The corrosion rate gained from this study revealed that samples with air cooling method showed lower corrosion rate compared to samples with quenching method. In potentiodynamic polarization study, the value of corrosion current density, I_corr increased with respect to immersion period. This behaviour signifies the occurrence of porosity where the air cooled samples show lower value of I_corr compared to quenched samples. The increase in I_corr causes the value of polarization resistance, R_p to decrease and corrosion rate to increase. The morphology study conducted revealed the existence of porosity and caused pitting corrosion on quenched samples which proved the samples with quenching method was more corroded as compared to samples with air cooling method.

The effect of different cooling methods on the corrosion behaviour at welded area of aluminium alloy 5083 was investigated by using weight loss study, potendynamic polarization study and morphology study. All samples were cooled by using air cooling method and quenching method. There was an increase of weight loss for both cooling methods where samples with air cooling method showed lower percentage of weight loss as compared to samples with quenching methods. The corrosion rate gained from this study revealed that samples with air cooling method showed lower corrosion rate compared to samples with quenching method. In potentiodynamic polarization study, the value of corrosion current density, I_corr increased with respect to immersion period. This behaviour signifies the occurrence of porosity where the air cooled samples show lower value of I_corr compared to quenched samples. The increase in I_corr causes the value of polarization resistance, R_p to decrease and corrosion rate to increase. The morphology study conducted revealed the existence of porosity and caused pitting corrosion on quenched samples which proved the samples with quenching method was more corroded as compared to samples with air cooling method.

The purpose of this paper is to study the inhibitory activity of benzene‐1,2,4,5‐tetracarboxylic dianhydride (PMDH) on aluminium corrosion in hydrochloric acid 1 M HCl.

The inhibitive effect of PMDH towards the corrosion of aluminium in 1 M HCl solution is studied by means of electrochemical impedance spectroscopy, polarization curves (LSV) and scanning electron microscopic techniques. The effect of inhibitor concentration and temperature against inhibitor action is investigated.

In the presence of inhibitor (PMDH), the corrosion resistance of aluminium is improved and the corrosion rate and corrosion current are reduced, therefore the inhibition efficiency and polarization resistance are increased. With increasing temperature and decreasing inhibitor concentrations, the rate of aluminium corrosion increased. The surfactant acts as mixed type inhibitor and obeys a Langmuir isotherm.

The results shown in this paper are an insight to the understanding of the corrosion resistance and electrochemical behaviour of aluminium for future industrial applications and development.

The purpose of this paper is to report the studies on the corrosion inhibition property of 4-amino-5-phenyl-4H-1,2,4-triazole-3-thiol (APTT) for the corrosion of 6061 Al-15 vol. pct. SiC(p) composite.

The corrosion behavior of 6061 Al-15 vol. pct. SiC(p) composite was studied at different temperatures in 0.5-M sodium hydroxide (NaOH) solution in the presence of APTT by potentiodynamic polarization (PDP) and electrochemical impedance spectroscopic techniques. The effect of inhibitor concentration and temperature on the inhibitor effect of APTT was studied. The surface morphology of the metal surface was investigated by scanning electron microscopy. The activation parameters for the corrosion of the composite and base alloy, as well as the thermodynamic parameters for the adsorption of APTT on the composite and alloy surfaces, were calculated.

The inhibition efficiency of APTT increases with the increase in the concentration of the inhibitor and decreases with the increase in temperature. The adsorption of APTT on the composite was found to be through physisorption, obeying Langmuir’s adsorption isotherm. APTT acts as a mixed inhibitor with predominant cathodic action on the composite.

APTT can be used as an inhibitor for the corrosion of 6061 Al-15 vol. pct. SiC(p) composite in the NaOH medium.

This paper provides information regarding the corrosion inhibition property of APTT on 6061 Al-15 vol. pct. SiC(p) composite. An attempt was made to explain the mechanism of the inhibition action by APTT.

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

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.

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.

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

The purpose of this paper is to investigate the effect of polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) and blended formulations on the corrosion inhibition of aluminium in HCl solutions at 30-60°C and to study the mechanism of action.

The inhibitive effect of the homopolymers and polymer blend was assessed using weight loss and hydrogen evolution methods at 30 and 60°C. The morphology of the corroding aluminium surface without and with the additives was visualized using atomic force microscopy. The trend of inhibition efficiency with temperature was used to propose the mechanism of inhibition and type of adsorption.

Results obtained show that inhibition efficiency (η%) increases with increase in concentration of the polymers but decreases with increase in temperature. The inhibition efficiency of the homopolymers and their blends decreased with rise in temperature. Inhibition efficiency was found to be synergistically enhanced on blending the two homopolymers with highest inhibition efficiency obtained for (PEG:PVP) blending ratio of 1:3. The phenomenon of physical adsorption is proposed from the trend of inhibition efficiency with temperature.

The mechanistic aspect of the corrosion inhibition can be better understood using electrochemical studies such as potentiodynamic polarization and electrochemical impedance spectroscopy.

Studies involving the use of polymer blends/mixtures as corrosion inhibitor for metals in corrosive environments are scarce. The results suggest that the mixture could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the use of polymer–polymer mixtures to control acid-induced corrosion of metal.

The purpose of this study is to research the effects of interrupted aging on the corrosion behavior of Al–Cu–Mg–Ag heat-resistant alloy by means of intergranular corrosion (IGC) testing, potentiodynamic polarization combined with optical microscopy and transmission electron microscopy.

The results show that the IGC began on the grain boundaries and continued along the grain boundary. The corrosion resistance property of Al–Cu–Mg–Ag alloy was enhanced by interrupted aging. The precipitations of the interrupted aged sample both in the grains and on the grain boundaries were fine, and the chain-like phases on the grain boundary were distributed nearly continuously.

The corrosion resistance of Al–Cu–Mg series Al alloy with equilibrium phase (Al₂Cu) is notably determined by precipitation-free zone (PFZ) as the self-corrosion potentials of (Al₂Cu), PFZ and the matrix satisfied the relation EPFZ < E_θ<EMatrix.

The connections of the PFZ on both sides of the grain boundary decreased the corrosion resistance of Al–Cu–Mg–Ag alloy treated by the single aging.

This paper reports an empirical examination of the societal, financial and technology-related challenges amid the ongoing pandemic (COVID-19) in the service supply chain network.

A combination of qualitative approach (for items generation pertinent to the constructs involved) and quantitative approach (self-administered questionnaires from the top and middle management of the sampled companies) was used for data collection. In total, 272 complete responses were received and analyzed through structural equation modeling.

The results provided empirical evidence that social and physical distancing, travel restrictions, work from home and lockdown practices have two conflicting effects: On one hand, these practices have contributed to the reduction of economic activities, including the low economic outlook, low productivity, high unemployment, poverty, fall in customer demands, dissatisfaction and mental health, that ultimately impacts rise financial and societal issues. On the other hand, the results revealed an insignificant influence of COVID-19 on creating technology-related challenges in the service sector. It shows that the organizations are doing well in combating the technology-related challenges amidst the current pandemic.

Findings of the inquiry recommend implications for the services industry to harmonize a comprehensive strategy and revisit the global norms in sustainable supply chain management activities that have been the backdrop in their operations for a long time.

Findings of the inquiry recommend implications for the services industry to harmonize a comprehensive strategy and revisit the global norms in supply chain management activities that have been the backdrop in their operations for a long time.

Prior studies in the context of the COVID-19 outbreak and its implications have given more attention to the exploratory and theoretical discussion than to empirical evidence. This paper contributes to filling this knowledge gap by empirically exploring the societal, financial and technology-related challenges created by COVID-19. The analysis in this paper covers three dimensions of the PEST model, namely economic, societal and technological factors. This study also helps in laying out a platform for investigating the PEST (political, economic, social and technological) model for guiding the services industry in strategic decision-making in a new era due to COVID-19.

This paper explores the new normal activities and strategic responses of the service industry towards the challenges created by the coronavirus disease 2019 (COVID-19) outbreak and other constructs and validates the measurement scale for socio-economic and technological new normal activities following lockdown and social distancing practices.

First, structured interviews with 28 participants helped us generate items and develop survey instruments for cross-sectional data collection in the second phase. So, the authors received 256 complete responses from the top and middle management of the services industry. Exploratory factor analysis helped us explore the factors and reliability of the items. Confirmatory factor analysis aided us in generating and confirming the factorial structure of the constructs.

Results indicated that amid COVID-19's pandemic, new normal activities are emerging in which organizations are deploying crisis strategies to safeguard their business and stakeholders. Organizations are re-opening swiftly, focusing on digital transformation, developing digital platforms for ease in working and improved consumer services, to name a few operational changes.

Discussion on empirical analysis revolves around the guidelines to service industry's managers and top management to improve shortcomings in combating the challenges they face in their operations.

Prior studies have provided substantial insights on the COVID-19 pandemic, but relatively little research exists on new normal activities in the supply chain network of the service industry. Among other reasons for such less empirical evidence on new normal activities is the unavailability of a comprehensive tool for measuring the socio-economic and technological new normal activities. This paper is a contribution to bridging this knowledge gap.

The global economy is plagued by an unprecedented shock that has devastated economic growth under the coronavirus pandemic. The prolonged movement control orders, social distancing, and lockdowns have triggered the global economic downturn, disrupted the demand and supply chains, reduced the pool of workforce, and caused many jobs loss. This paper aims to analyze the global economic cost of the coronavirus pandemic, and its current and future implications.

Based on contingency theory, this paper provides an in-depth analysis of the current situation on the global economic cost of the COVID-19 outbreak and gives insights from an organizational perspective.

This paper found that the world has witnessed far-ranging economic consequences due to the coronavirus pandemic in four aspects: (i) decline in personal consumption; (ii) decline in the investments and stock prices in capital market; (iii) decline in government spending in developmental projects and increase in new borrowing; and (iv) decline of exports of goods to international markets.

The novelty lies in investigating the effects of the COVID-19 pandemic on micro and macroeconomic levels — the components of GDP, consumer behavior, business investments, government spending, and global exports. The paper suggests the need for urgent actions by the world leaders to oversee, anticipate, and manage the risks and cushion the economic consequences. It concludes that the flexibility and adaptability of leaders, effectiveness, workforce protection, efficient use of modern technology, including automation and artificial intelligence, would enhance the resilience of supply chains which will support organizations to sustain in this critical time.