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The galvanic corrosion interactions of zinc and SS.304 have been studied in a tropical marine environment over a period of 427 days, under different area ratios. The galvanic interaction of zinc and SS.304 are highlighted in terms of the corrosion rate of zinc or SS.304 resulting from galvanic coupling, and the susceptibility of zinc to pitting due to galvanic corrosion. The galvanic potential and galvanic current of the system are monitored. The corrosion products at the interface of the bimetallic contacts are analysed with XRD technique and the pitting/grooving on zinc resulting from galvanic corrosion is measured using a high resolution microscope. The weathering parameters and environmental pollutants are monitored to give an insight into the possible means of favouring the galvanic interactions. The results of the study are discussed in the light of the above factors towards predicting a mechanism for the galvanic interactions of zinc and SS.304.

It is now fairly well established that steel reinforcements need some additional protection and various types of coatings such as fusion‐bonded epoxy, galvanizing and cement slurry have been used. Evaluation of such coated rebars in aggressive marine conditions is done usually by conducting some accelerated corrosion tests. These accelerated corrosion tests cannot be truly representative of field conditions and they often give higher corrosion rates. Validity of such tests becomes questionable. In the present work, corrosion rates of cement slurry‐coated rebars, obtained by ASTM impressed voltage test, salt‐spray test, precracked cantilever model slab test, alternate wetting and drying test and macrocell corrosion test, have been compared with uncoated rebars. It is shown that for a passivating type of coating such as cement slurry, accelerated corrosion tests could be equally valid.

The criteria importance through intercriteria correlation (CRITIC) and range of value (ROV) combined methods were used to determine a single index for all multiple responses.

This paper used cold metal transfer (CMT) and pulse metal-inert gas (MIG) welding processes to study the weld-on-bead geometry of AA2099-T86 alloy. This study used Taguchi's approach to find the optimal setting of the input welding parameters. The welding current, welding speed and contact-tip-to workpiece distance were the input welding parameters for finding the output responses, i.e. weld penetration, dilution and heat input. The L9 orthogonal array of Taguchi's approach was used to find out the optimal setting of the input parameters.

The optimal input welding parameters were determined with combined output responses. The predicted optimum welding input parameters were validated through confirmation tests. Analysis of variance showed that welding speed is the most influential factor in determining the weld bead geometry of the CMT and pulse MIG welding techniques.

The heat input and weld bead geometry are compared in both welding processes. The CMT welding samples show superior defect-free weld beads than pulse MIG welding due to lesser heat input and lesser dilution.

Medical textile is one aspect of technical textiles and it is classified according to performance and functional properties for hygienic and healthcare products. Seaweeds have curative powers for curing most degenerative diseases. The paper aims to discuss these issues.

The present study focusses on the extraction of dyes from five seaweeds such as Ulva reticulata, Ulva lactuca, Sargassum wightii, Padina tetrastomatica and Acanthophora spicefera. The presence of bioactive compounds, antioxidant and antimicrobial properties of dye extracted from seaweeds was analysed. The dye extracted from green seaweed was applied on cotton fabric to obtain antimicrobial and other properties used to make non- implantable materials.

A maximum antioxidant inhibition percentage of 86.48+2.84 and a maximum antibacterial activity of 27 mm inhibition zone were obtained on the fabric treated with the dye extract from the Ulva lactuca seaweed. The physical properties such as tensile strength and tearing strength did not show much significant difference in untreated and treated fabric. The air permeability, water absorbency and wicking behaviour of treated fabric were reduced compared with untreated fabric. The washing and rubbing properties of treated fabric were very good after repeated washing.

This bioactive fabric has been used for non-implantable materials such as wound healing, face mask, surgical gowns and hygienic textiles in recent years.

This study examines the dynamic linkages between the Indian Nifty index futures traded on the offshore Singapore Exchange (SGX) and US stock indices (DJIA, NASDAQ and S&P 500) under the closure of the spot market for Nifty futures.

With high-frequency 5-min overlapping price data, the authors employ the Johansen cointegration test to investigate long-run relationships, the Granger causality test to assess short-run dynamics and the BEKK-GARCH model for volatility spillover investigation.

The empirical findings reveal that the SGX Nifty futures market is cointegrated with the US DJIA market. The US DJIA stock index strongly influences the price discovery of SGX Nifty futures and past innovations in the US markets strongly impact the current volatility of SGX Nifty futures.

Findings from this study have significant implications for market participants, particularly foreign investors and portfolio managers. These findings might be helpful for market participants to improve the prediction power of expected SGX Nifty futures price and volatility, especially under the closure of the spot market. Also, SGX market participants can take the significant role of the US market into account when formulating hedging and trading strategies with Indian Nifty futures. Besides, our findings have significant implications for policymakers in evaluating market stability.

This article adds to the very limited research on offshore or international stock index futures; it is the first study that empirically examines the international linkages of offshore SGX Nifty futures under the closure of its underlying spot market and also the driving force behind the linkages.

This study empirically explores the intraday price discovery mechanism and volatility transmission effect between the dual-listed Indian Nifty index futures traded simultaneously on the onshore Indian exchange, National Stock Exchange (NSE) and offshore Singapore Exchange (SGX) and its spot market by using high-frequency data.

This study applies the vector error correction model to analyze the lead-lag relationship in price discovery among three markets. The contributions of individual markets in assimilating new information into prices are measured using various measures, Hasbrouck's (1995) information share, Lien and Shrestha's (2009) modified information share and Gonzalo and Granger's (1995) component share. Additionally, the Granger causality test is conducted to determine the causal relationship. Lastly, the BEKK-GARCH specification is employed to analyze the volatility transmission.

This study provides robust evidence that Nifty futures lead the spot in price discovery. The offshore SGX Nifty futures consistently ranked first in contributing to price discovery, followed by onshore NSE Nifty futures and finally by the spot. Empirical results also show unidirectional causality and volatility transmission from Nifty futures to spot, as well as bidirectional causal relationship and volatility spillovers between NSE and SGX Nifty futures. These novel findings provide fresh insights into the informational efficiency of the dual-listed Indian Nifty futures, which is distinct from previous literature.

These findings can potentially help market participants, policymakers, stock exchanges and regulators.

Unlike previous studies in this area, this is the first study that empirically examines the intraday price discovery mechanism and volatility spillover between the dual-listed futures markets and its spot market using 5-min overlapping price data and trivariate econometric models.

The spread of broadband Internet has resulted in the increase of spyware and adware. This study highlights their damaging effects and proposes a model that captures defensive measures adopted by Internet users. Specifically, our model indicates that knowledge has a positive impact on self‐efficacy that, in turn, is presumed to trigger technical defensive measures. Moreover, concerns for privacy and previous experience with spyware and adware are likely to evoke both tactical and technical defense measures. Data collected by the PEW Internet and American Life research project are utilized to test the proposed model and the findings are discussed.

This study aims to evaluate the influence of corporate governance index (CGI), ownership concentration (OC) and other features on the dividends of listed Indian pharmaceutical companies. The other features included are leverage, excess return over cost of equity and stock-market return. This study thus helps to provide more insights on the dividend distribution issues for a shareholder in the challenging and demanding pharma industry, especially when stakes are high.

The data for all 26 pharmaceutical companies which form part of the NSE NIFTY-500 index for six years (2014–2019) is procured using Centre for Monitoring Indian Economy’s (CMIEs) Prowess database. An eight-pointer scale (unweighted scale) is used to develop the CGI. For OC, this paper considers the proportion of promoters’ shareholding, domestic institutional investors’ shareholding and foreign owners’ shareholding. Both static and dynamic panel data models are used to evaluate the effect of CGI and OC on dividends.

The panel data analysis depicts that CGI significantly positively influences the dividends of pharmaceutical companies in India. Thus, the authors find support for La Porta et al.’s outcome agency model. The results also reveal that only promoters’ holdings are significantly inversely related to dividends out of the three OC variables used for this study. This discussion implies that family-run pharmaceutical companies in India tend to retain profits instead of distributing dividends.

This study provides two direct insights for policymakers and stakeholders. First, because this study shows that CGI significantly positively influences dividends, corporate governance (CG) is an essential factor for determining dividends. Second, because the results also reveal that OC in the hands of promoters hurts dividends, it implies that the higher the promoter holding, lesser is the dividend distributed by the company. Both these results can be used as a quantitative tool by investors to assess Indian pharmaceutical companies better. However, a similar study could be directed to assess the impact of CGI and OC on dividends of other industries. Moreover, additional variables of CG and OC can also be evaluated in further detail. There is also a need to empirically validate the impact of CG and OC on a company’s performance.

The results are robust and reveal that variation in CGI does impact dividend policy. This aids in confirming that CG is a crucial aspect influencing dividends. The findings also add to the increasing studies across the globe evaluating the influence of CG and OC on dividends.