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Silicon-containing groups were introduced into fluoroacrylate polymer to further improve the comprehensive performance of pressure-sensitive adhesive (PSA) for expanded polytetrafluoroethylene (ePTFE) bonding.

A series of silicon-containing fluorinated acrylic copolymers were synthesized through free radical solution polymerization with vinyloxy trimethylsilane, allyltrimethylsilane, 3-(trimethoxysilyl)propyl methacrylate or 1,3,5-tris(3,3,3-trifluoropropyl) methylcyclotrisiloxane as silicon monomers, and comprehensive performance of the copolymers was evaluated based on Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), gel permeation chromatography, glass transition temperatures (T_g), differential scanning calorimetry, thermogravimetric analysis, water contact angle, the track, 180° peel strength, and shear holding power.

Based on the FTIR and XPS results, it is confirmed that the silicon monomers were successfully introduced into the fluorinated acrylate copolymer. XPS analysis indicated that the silicon groups had the tendency to enrich on the surface of the film, thereby reducing the F content on the film surface. The glass transition temperatures (T_g) of the PSAs increased when silicon monomers were introduced, while the thermal stability declined. The contact angles of the acrylic PSA films were increased with the introduction of silicon monomers. From the perspective of bonding performance, the track, 180° peel strength and shear holding power decreased to varying degrees compared to silicon-free PSA, except significantly elevated holding power with MPS as the silicon monomer.

Silicon-containing fluorinated acrylic copolymers were synthesized, and the comprehensive performance was evaluated as PSAs of ePTFE for the first time.

This study investigates the influence of trading mechanisms on cross-market integration between stocks and corporate bonds on the Tel Aviv Stock Exchange (TASE) during the COVID-19 crisis. Unlike the worldwide practice of trading corporate bonds on an over-the-counter (OTC) market, TASE uses a limit-order-book (LOB) for both stocks and bonds, potentially creating unique volatility dynamics through direct information spillover. We analyze the volatility dynamics and spillover effects between TASE’s stock and corporate bond markets.

We employ an exponential general autoregressive conditional heteroskedastic (EGARCH)(1,1) model to assess the impact of stock market fear, measured by implied volatility, on Tel-Bond 20 Index returns and volatility. A bivariate diagonal Baba-Engle-Kraft-Kroner (BEKK) model is also applied to capture time-series integration and cross-volatility spillovers between the TA-35 Index (stocks) and the Tel-Bond 20 Index (corporate bonds), especially during financial stress.

The EGARCH model reveals a significant contagion effect, with increased stock market fear lowering corporate bond returns and increasing bond volatility. It also indicates a leverage effect, where negative shocks disproportionately amplify bond volatility. Diagonal BEKK results confirm strong cross-market volatility persistence, especially during crises, highlighting substantial financial contagion between stocks and bonds in TASE. While TASE’s market design improves the overall market quality, these findings underscore the LOB trading mechanism in facilitating financial contagion and systemic risk.

The LOB trading in TASE facilitates direct information flow, intensifying volatility spillover and cross-market integration, with the degree of integration fluctuating based on market conditions. Investors and managers should consider alternative hedging strategies during volatile periods, as stock market sentiment significantly impacts bond stability. Regulators should assess how trading mechanisms affect market integration and risk, especially during periods of distress.

This study offers new insights into how trading mechanisms influence cross-market dynamics, contributing to the literature on market design and financial contagion.

The construction industry’s pursuit of sustainable and high-performance materials has led to the exploration of alternative aggregates and innovative additives. This paper investigates the combined influence of recycled aggregates (RA) and nano TiO₂ particles on M20 and M30 concretes, addressing ecological concerns and seeking to improve material properties. RA, sourced from construction and demolition waste, presents a sustainable solution to alleviate the environmental impact associated with traditional virgin aggregates (VA). However, challenges related to the mechanical strength and durability often hinder the widespread use of RA in concrete. This study aims to bridge this gap by exploring the reinforcing potential of nano TiO₂ particles.

Nanomaterial such as TiO₂ is known for its photocatalytic properties and reinforcement capabilities and has emerged as a promising additive in construction materials. The investigation herein involves the incorporation of nano TiO₂ at percentages of 0.5% and 1% in both VA- and RA-based M20 and M30 concretes. Comprehensive series of tests on mechanical, durability and microstructural properties are conducted for each concrete mix.

Results unequivocally indicate that the addition of TiO₂ significantly improves the properties of concrete, with RA-based concrete exhibiting performance comparable to that of VA-based counterparts. This breakthrough suggests a viable application of RA with TiO₂ in construction projects, promoting sustainability without compromising performance. Following experimental analyses, linear regression and multiple linear regression analyses are used to establish predictive equations correlating interfacial transition zone (ITZ) thickness with TiO₂ percentage, compressive strength, tensile strength, flexural strength and chloride penetration.

These equations serve as valuable tools for predicting ITZ thickness in future concrete formulations based on specified parameter quantities, thereby contributing to informed decision-making in sustainable construction practices. The findings of this study have the potential to contribute to the improvement of environmentally conscious construction methods while also improving the performance and durability of concrete structures.

The purpose of this study is to develop a protective coating system on mild steel panel incorporating epoxidized natural rubber with acrylic polyol resin.

In this work, a novel attempt is made to develop binder coatings using epoxidized natural rubber-based material and an organic resin (acrylic resin) for corrosion protection on metal substrate. Seven different samples of multifunctional coatings are developed by varying the compositions of epoxidized natural rubber (ENR) and acrylic resin. The properties of the developed coatings have been characterized using analytical methods such as Fourier transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS). EIS has been carried out for 30 days to evaluate the corrosion resistance after immersing into 3.5 wt.% of sodium chloride. Cross hatch cut tester (CHT) has been used to study the adhesive properties. UV–Visible Spectroscopy (UV–Vis) was also used to assess changes in the coating-film transparency of the natural rubber-based coating systems in this study.

The developed coatings have formed uniform layer on the substrate. CHT results show excellent adhesion of the coatings. Higher concentrations of ENR have higher transparency level, which reduces when the acrylic concentration increases. FTIR analysis confirms the crosslinking that occurred between the components of the coatings. Based on the impedance data from EIS, the incorporation of natural rubber can be an additive for the corrosion protection, which has the coating resistance values well above 108Ω even after 30 days of immersion.

The blending method provides a simple and practical solution to improve the strength and adhesion properties of acrylic polyol resin with epoxidized natural rubber. There is still improvement needed for long-term applications.

The work has been conducted in our laboratory. The combination of natural rubber-based materials and organic resins is a new approach in coating research.

The purpose of this study is to develop a green corrosion inhibitor (GCI) from the parthenium hysterophorus (PHS) leaf and identifying its efficiency in corrosion inhibition of AZ31 alloy.

GCI from PHS leaf is extracted with the aid of Soxhlet apparatus and analysed through Fourier transform infrared spectroscopy (FTIR) and phytochemical tests to identify the functional groups and chemical compounds present. Inhibition efficiency (IE) of PHS extract is identified through polarization analysis and immersion tests in which concentration of PHS extract (0–300 ppm) and temperature (303–353 K) is varied.

Maximum IE of 84% is exhibited by the prepared PHS extract at a concentration of 250 ppm at 303 K and further addition diminishes IE. The developed GCI is found effective in room temperature (303 K) as it exhibits lower IE when temperature increased. Both physical and chemical absorption mechanisms were identified for PHS extract over AZ31 surface, whereas FTIR and SEM analysis confirms the development of passivation layer.

Development of GCI from the leaf of a weed (PHS) that disturbs the ecosystem and identifying its efficiency in preventing corrosion of AZ31 under saline environment.

This study aims to provide data references for deposit cleaning, fuel formulation and lubricant formulation.

The engine disassembly procedure was carried out based on the IO540 operation manual part number 60297-10-1-7 document. Except for the normal disassembly and assembly of the engine and the measurement of parts, the main test contents included break-in run operation, cylinder pressure test, oil consumption run, pretest calibration run, post-test calibration test and the most critical endurance test. The Lycoming IO-540-V4V5 engine and the customized Hartzell CK319 propeller were selected for the test run.

The deposits were mainly composed of C, O, B, Al, Br and Pb, which were mainly sourced from fuel, lubricating oil and body materials. XPS analysis showed that the presence of O determined the richness of the deposit components, giving the deposit structure with organic and inorganic components.

This work provides certain data support and reference for subsequent aircraft maintenance, fuel formula and lubricating oil formula. The long-term stability and safety of the aircraft run can be ensured through continuous research, improvement and optimizing the operating of the engine.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2024-0300/

This paper aims to develop carbon dots using whey as a valuable resource and to create a sustainable and biocompatible nanomaterial with potential applications in a variety of fields owing to its unique optical properties and antimicrobial capabilities, which are frequently used as sensing agents for detecting specific molecules in food, environmental and biomedical applications. Versatility of carbon dots (CDs) allows the utilization of these dots for a wide range of applications in areas such as food safety, antibacterial properties, production of composite polymers for food packaging, treatment of different diseases and detection of food-borne pathogens. Owing to their high brightness, low toxicity and excellent biocompatibility, CDs have attracted significant interest in food safety. This is also a cutting-edge technology that bids new ideas for treating various diseases.

Literature review related to using whey as the carbon source for synthesis of CDs was collected and studied from different sources like Google Scholar, Research Gate, online journals available at library of Banaras Hindu University, Web of Science and Scopus. A database of more than 100 scientific sources from different sources was made as per the headings and sub headings of the paper.

Whey generated as a by-product from the cheese industry contained a good amount of carbon and nitrogen that can be used for the fabrication of CDs. CDs produced using whey exhibited great photostability, high sensitivity and outstanding biocompatibility and also showed that Fe3+ ions could be quickly, sensitively and extremely selectively detected in an aqueous solution of CDs, with a revealing limit of 0.409 µM in the linear range of 0–180 µM. CDs are a promising area of study to a key component of next-generation multifunctional nanomaterials, promoting creativity, sustainability and useful solutions across a variety of industries, including health care and energy. The susceptibility of S. typhimurium (Gram-negative) was found to be higher than that of L. monocytogenes (Gram-positive) bacteria with MIC and MBC of 500  and 1000 µL/mL, respectively.

Whey-derived CDs are an environmentally beneficial substitute for conventional additives and their biocompatibility guarantees that they adhere to food safety regulations. In light of the future, the green volarization of dairy waste for the synthesis of CDs is consistent with the increasing worldwide focus on environmental responsibility and sustainability.

The main purpose of this study is to examine the effect of corporate digital transformation on bond credit spreads. Additionally, it also explores the two potential channels, information asymmetry and default risk, through which digital transformation can influence bond credit spreads.

We use the bond issuance data of Chinese listed companies over the period 2008–2020. Corporate digital transformation of these companies is measured with textual analysis of the management discussion and analysis part of annual reports. We employ a panel regression model to estimate the effect of digital transformation on bond credit spreads.

We find robust evidence that companies with higher digital transformation experience lower bond credit spreads. We further observe that credit spread reduction is higher for firms that are smaller, non-state-owned, have lower credit ratings and have less analyst coverage. We also find evidence that digital transformation reduces credit spreads by reducing the information asymmetry between firms and investors with enhanced information transformation mechanisms and lowering corporate default risk by strengthening operating efficiency.

To the best of our knowledge, this study is the first attempt to understand the impact of corporate digital transformation on bond credit spreads. Our findings help to understand the effect of digital transformation on firms’ credit worthiness and access to capital.

This paper aims to unveil the greenwashing intention of green bonds issuing in Chinese enterprises through the lens of stock pricing efficiency.

Drawing on data of Chinese listed companies during 2012–2021, this study uses a difference-in-differences method to study how and through what mechanisms issuing green bonds impacts stock pricing efficiency.

Issuing green bonds lowers stock pricing efficiency, verifying the greenwashing intention of green bonds in China. Potential mechanisms underlie the increased investor attention and sentiment resulting from the information disclosures about corporate green and low-carbon development. This greenwashing issue is more pronounced in firms facing lower financing constraints, having stronger relations with the government, and located in highly marketized regions. In the context of uncertainty surrounding economic policies, especially trade policies, issuing green bonds can signal a weakening of the greenwashing effect.

The quality of information disclosure should be emphasized to ensure a substantive commitment to environmental responsibility signaled by green bond issuance, thereby mitigating greenwashing concerns.

Regulators and standard-setters should improve the issuance system for green bonds and promote the sustainable development of the green bond market through formulating unified certification criteria for green bonds and implementing a stringently periodic reporting system.

First, to the best of the authors’ knowledge, it is the first study to draw on the quality of information disclosure and the perspective of stock pricing efficiency to identify whether firms issuing green bonds engage in greenwashing. Second, the study uncovers the black-box underlying this greenwashing issue through investor attention and sentiment and examines further the moderating role of economic policy uncertainties.

This paper examines the effect of bond market development on economic growth of selected developing countries from 1990 to 2020. Previous studies provide inconsistent results on the effect of bond market development on economic growth. Some results reveal positive effects while others show negative effects of bond market development on economic growth. These conflicting findings have motivated research.

The autoregressive distributed lag (ARDL) and co-integration methods are used for analysis. The gross domestic product per capita proxies economic growth while government bond capitalisation and corporate bond capitalisation measure bond market development.

The findings unveil a long-term effect within the series. The results disclose that government bond capitalisation, trade openness and inflation positively affect economic growth while corporate bond capitalisation and domestic credit to the private sector presents negative effects on economic growth.

The results propose that the governments should issue more bonds to raise funds for long-term economic growth initiatives. The governments should promote bond market development such that the corporate bonds issued boost economic growth by limiting lengthy documentations and bottlenecks in the bond market listing and issue procedures. The policymakers and regulatory authorities should implement policies which attract investors and encourage companies' listing in the countries' bond markets.

The study’s findings add value that government bond capitalisation positively impacts economic growth, while corporate bond capitalisation negatively affects economic growth in developing countries.