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This study aims to develop synthetic ester lubricating oil using renewable sinapic acid as raw material, to explore the structural design and selection of raw materials for green, high-performance synthetic ester oils.

A series of the sinapate ester oils were synthesized through esterification and alkoxylation reactions using renewable source sinapic acid as the raw material. The molecular structures of the oils were characterized by nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy spectroscopy and elemental analysis. The oils were evaluated for safety, viscosity-temperature properties, thermal and oxidative stability, as well as friction reducing and anti-wear characteristics.

Compared to commercial base oil tris (2-ethylhexyl) trimellitate (Phe-3Ci8), the bio-lubricant exhibits superior antifriction and anti-wear properties. Notably, the JCi8-C12 sample performed exceptionally well, reducing the friction coefficient by 11.42% and wear volume (WV) by 54.44% in steel/steel tribo-pairs. In steel/aluminum tribo-pairs, the friction coefficient decreased by 27.48%, while WV was reduced by 85.81%. Mechanistic studies reveal that the introduction of short-chain methoxy groups and stable conjugated systems (aromatic rings and double bonds) inhibit oxidation and decomposition at elevated temperatures. The p-p stacking effect enables lubricant molecules to arrange stably on friction surfaces, forming a durable lubricating film.

The utilization of biomass resources to develop green synthetic lubricating oil with excellent performance not only enhances the added value of waste from agricultural processing but also offers significant benefits in terms of both economic and environmental sustainability.

The underground logistics system (ULS) is noted to be an innovative delivery alternative that confers benefits such as improved logistics efficiency, reduced traffic congestion and better environmental protection for society. Consumer acceptance is crucial for the widespread application of ULS. Hence, this study aims to explore the drivers affecting consumers’ willingness to adopt an ULS anchored on the uses and gratification theory.

An online survey was implemented among 551 Singapore citizens and structural equation modeling was adopted to examine the theoretical model.

The findings suggest that most gratification variables (i.e. hedonic gratification, environmental protection gratification (EPG) and social gratification), mediated by perceived well-being and conscious attention, have significant effects on consumer adoption of the ULS. Moreover, as shown in the results of total effects, well-being perception exerts the largest impact on consumers’ adoption of ULS, followed by conscious attention, EPG, social gratification, hedonic gratification and convenience gratification.

This study contributes to enriching current theoretical research on consumers’ willingness to accept ULS, and providing several practical implications for logistic service providers and the government to promote consumers’ adoption of ULS.

This study addresses a gap in understanding consumer retention in omnichannel retailing. It explores the impact of omnichannel capabilities on consumer retention by examining the roles of consumer empowerment, cross-channel integration, retailer uncertainty and consumer satisfaction.

Utilising the stimulus-organism-response theory, data from 338 Indian omnichannel consumers were analysed using SmartPLS V3 and Process Macro for SPSS. A structured questionnaire guided the investigation into the interconnected dynamics of omnichannel capabilities, consumer empowerment, cross-channel integration, retailer uncertainty and consumer satisfaction.

Findings suggest that omnichannel capabilities significantly and positively influence consumer retention, with a significant mediation impact on consumer empowerment and cross-channel integration. The results indicate that retailer uncertainty negatively moderates, whereas consumer satisfaction positively moderates the association between omnichannel capabilities and consumer retention. Moreover, the study unravels the mechanisms driving consumer retention in the omnichannel landscape.

This research pioneers unravelling the complexities of consumer retention in omnichannel retailing. It explores how consumer retention is enhanced through omnichannel capabilities. This study bridges a gap in existing research by examining the impact of omnichannel capabilities, consumer empowerment and cross-channel integration in omnichannel retailing. Therefore, this study provides innovative, unique and strategic adaptations in the retail industry.

This paper aims to investigate the crucial roles of textured surfaces on oil-impregnated polytetrafluoroethylene (PTFE) created by a facile tattoo strategy in improving tribological properties.

Pored PTFE (PPTFE) was prepared by mixing powder PTFE and citric acid and experienced a cold-press sintering molding process. Subsequently, textured surfaces were obtained with using a tattoo strategy. Surface-textured PPTFE was thus impregnated with polyethylene glycol 200, yielding oil-impregnated and pore-connected PPTFE.

This study found that oil-impregnated and surface-textured PPTFE exhibited excellent tribological performances with an 82% reduction in coefficient of friction and a 72.5% lowering in wear rate comparing to PPTFE.

This study shows an efficient strategy to improve the tribological property of PTFE using a tattoo-inspired surface texturing method.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2024-0378/

This study examines the impact of female directors on cash holdings in Egyptian listed firms, particularly in light of Decree 123/2019, which mandates female board representation. This study aims to determine if female directors mitigate agency conflicts related to cash holdings and how these dynamics shift post-quota implementation.

Using a panel fixed-effects model, the research analyzes 1,563 firm-year observations from 223 non-financial Egyptian firms listed on the EGX between 2014 and 2022. The robustness of the findings is tested through additional analyses using alternative proxies for cash holdings, different sample periods and a two-stage least squares approach to address endogeneity concerns.

This study finds a significant negative association between female directors and cash holdings, suggesting that female board members may promote more conservative cash management practices. However, this relationship weakens post-quota implementation, becoming statistically insignificant. This implies that while quotas increase female representation, they do not necessarily enhance corporate governance effectiveness regarding cash management. The pre-quota positive link between female directors and excess cash holdings also becomes insignificant post-quota.

The study focuses on female directors’ impact on cash holdings, excluding potential effects on other board subcommittees or functions. It does not capture long-term benefits of increased female representation, which may emerge as the pool of qualified female directors grows. Future research should explore broader implications of gender diversity guidelines and other diversity dimensions across various corporate governance aspects and institutional contexts.

This research provides empirical evidence from an emerging market context on the understudied impact of gender diversity on cash holdings. It critically evaluates the unintended consequences of mandatory gender quotas, highlighting the complexity of regulatory interventions in corporate governance. The study stresses the need for policymakers to address factors limiting the effectiveness of such quotas and to consider potential suboptimal outcomes when increasing female board representation without a corresponding increase in the supply of qualified female directors.

Based on the perspective of knowledge management, this study aims to discuss how to build cross-city emergency management collaboration mechanism in major emergencies and explore the important role of knowledge management in emergency management collaboration.

Based on the theoretical analysis of knowledge management and the typical case study of cross-city emergency management collaborative rescue, this study provides an in-depth analysis of how these cities achieve high emergency management performance through multidimensional and multilevel knowledge collaboration, thus revealing the mechanism of knowledge transfer, integration and sharing in achieving high emergency management performance.

Through analyzing typical cases, this study finds that building a smooth mechanism for multichannel emergency rescue information can promote the diversification of knowledge transfer methods, building a platform-based integration mechanism for emergency rescue information can enhance knowledge integration capabilities and building a linkage mechanism for emergency rescue materials between cities can promote knowledge-sharing level, thereby improving emergency management performance level.

This study has great significance for how to build cross-city emergency management collaboration mechanism in the digital era. In the future, the authors need to further discuss the following two aspects in depth: research on the impact of cross-city emergency management collaboration mechanism on improving the knowledge management capabilities of government emergency management departments; and research on the impact mechanism of knowledge management capabilities on city resilience.

Through case analysis of cross-city emergency management collaborative rescue for major emergencies in China in recent years, this study proposes three specific strategies for cross-city emergency management (smooth, integration and linkage mechanisms) and reveals that these three strategies are essentially aimed at improving the government’s knowledge management level.

The purpose of this study is to reveal the significant contribution of MXene on enhancing tribological properties and to obtain the influence mechanism of various factors on friction characteristics of rolling bearing under extreme conditions.

Under extreme working conditions, the friction characteristics of rolling bearings directly determine the safety and reliability of the transmission system. In this study, MXene is added to the origin lubricating grease (OLG) of rolling bearing to enhance their friction characteristics. Then, the effects of inner ring speed, radial load, grease filling volume and other factors on the friction coefficient of rolling bearing are analyzed using the Taguchi method.

The results indicate that the ranking of various factors affecting the friction coefficient is: radial load, inner ring speed, MXene additive content in grease and grease filling volume. Especially, the radial load and inner ring speed exhibit extremely significant effects, while the MXene additive content in grease (P < 0.05) has a significant influence on the friction coefficient of rolling bearing. The optimal condition for rolling bearing lubricated with MXene additives lubricating grease (MALG) achieves the lowest friction coefficient of 0.0049 under 1,000 rpm, 9 kN and 35% grease filling volume.

This study could offer reference solution for utilizing MXene nano-lubrication to fufill the demands of precision, heavy-load, or long-lifespan bearings. Furthermore, the lubrication approach has the potential to be expanded into aerospace, defense, and various industrial fields, thereby significantly promoting its practial engineering applications.

Given the interest in sustainable development, this study aims to assess the relationship between CO₂ and urbanization as well as the role of world uncertainty in this association in a South African context.

This study focuses on yearly data from 1968 to 2020. To do this, the authors use the autoregressive distributed lag (ARDL) approach.

The authors find that urbanization’s effect on CO₂ emissions is only significant when it is augmented with world uncertainty. Moreover, this effect is negative (referring to a reduction in CO₂ emissions). Meanwhile, the authors find that GDP has a positive (that is, increasing) and significant effect on CO₂ emissions. Overall, policymakers should focus on decoupling economic growth from traditional fossil fuels that produce greenhouse gas emissions.

The existing body of research contains numerous studies examining the relationship between urbanization and CO₂ emissions. However, the dearth of research on the impact of global uncertainty on this connection is weak. Hence, this study aims to fill this gap and make a significant contribution to the field.

The present study explored the interrelationships between intellectual capital (IC) dimensions, inbound open innovation (IOI) and construction firm performance.

A quantitative approach was chosen for this study. Data were collected from 130 construction firms in Ghana using survey questionnaires. Partial least squares structural equation modelling was employed to test the hypotheses of the study.

The results indicate that while human capital and structural capital both have direct effects on IOI, relational capital does not. IOI positively influences firm performance (FP) linearly but shows a curvilinear (inverted U-shaped) relationship with FP at higher levels of IOI. IOI has a partial mediating effect in the relationships between human or structural capital and FP but does not show any mediation between relational capital and FP.

To the best of the authors’ knowledge, this study is among the first to explore the influence of inbound open innovation on the performance of project-based firms, such as construction, as well as the role of inbound open innovation as a mediator between firms’ intellectual capital and performance in the general management and the construction management literature.

Damage of engineering structures is a nonlinear evolutionary process that spans across both material and structural levels, from mesoscale to macroscale. This paper aims to provide a comprehensive review of damage analysis methods at both the material and structural levels.

This study provides an overview of multiscale damage analysis of engineering structures, including its definition and significance. Current status of damage analysis at both material and structural levels is investigated, by reviewing damage models and prediction methods from single-scale to multiscale perspectives. The discussion of prediction methods includes both model-based simulation approaches and data-driven techniques, emphasizing their roles and applications. Finally, summarize the main findings and discuss potential future research directions in this field.

In the material level, damage research primarily focuses on the degradation of material properties at the macroscale using continuum damage mechanics (CDM). In contrast, at the mesoscale, damage research involves analyzing material behavior in the meso-structural domain, focusing on defects like microcracks and void growth. In structural-level damage analysis, the macroscale is typically divided into component and structural scales. The component scale examines damage progression in individual structural elements, such as beams and columns, often using detailed finite element or mesoscale models. The structural scale evaluates the global behavior of the entire structure, typically using simplified models like beam or shell elements.

To achieve realistic simulations, it is essential to include as many mesoscale details as possible. However, this results in significant computational demands. To balance accuracy and efficiency, multiscale methods are employed. These methods are categorized into hierarchical approaches, where different scales are processed sequentially, and concurrent approaches, where multiple scales are solved simultaneously to capture complex interactions across scales.