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The purpose of this paper is to investigate thermal properties at Cu/Al interfaces.

A hybrid (molecular dynamics-interface stress element-finite element model (MD-ISE-FE) model is constructed to describe thermal behaviors at Cu/Al interfaces. The heat transfer simulation is performed after the non-ideal Cu/Al interface is constructed by diffusion bonding.

The simulation shows that the interfacial thermal resistance is decreasing with the increase of bonding temperature; while the interfacial region thickness and interfacial thermal conductivity are increasing with similar trends when the bonding temperature is increasing. It indicates that the higher bonding temperature can improve thermal properties of the interface structure.

The MD-ISE-FE model proposed in this paper is computationally efficient for interfacial heat transfer problems, and could be used in investigations of other interfacial behaviors of dissimilar materials. All these are helpful for the understanding of thermal properties of wire bonding interface structures. It implies that the MD-ISE-FE multiscale modeling approach would be a potential method for design and analysis of interfacial characteristics in micro/nano assembly.

The purpose of this paper is to develop a systematic experimental investigation for testing dynamic behavior of plastic ball grid array (PBGA) integrity in electronic packaging and to investigate the dynamic behavior of PBGA assembly by considering fixed‐modes for design and reliability evaluation of PBGA packaging.

A PBGA assembly prototype with different structure and material parameters is designed and manufactured. The modal distribution under excitation cycling can be tested by hammering test. The dynamic test about the PBGA assembly prototype can be implemented with different structure characteristics, materials parameters and fixed‐modes. To illustrate the validity of experimental test, the numerical simulation for the dynamic behavior of the PBGA assembly prototype is developed by using finite element method. Comparison between the experimental results and simulation can illustrate the validity of the experimental test and finite element modeling each other.

The modal distribution test shows the influence of structure characteristics, materials parameters and fixed‐modes of PBGA assembly board. The changing trends of the dynamic modal characteristics during the dynamic excitation can be obtained with different structure characteristics, materials parameters and fixed‐modes of PBGA assembly. Test shows that the fixed location of the assembly board is the most important factor to influence the first frequency and modal deformation of the assembly board. Higher frequency and smaller deformation can be obtained when there are more constraints in printed circuit board.

The numerical model is a compendious model by predigesting structure. The research on more accurate mathematical model of the PBGA assembly prototype is a future work.

It can imply the dynamics of PBGA assembly. It builds a basis for future work for design and reliability evaluation of PBGA packaging.

This paper provides useful information about the dynamic behavior of PBGA assembly with different structure characteristics, materials parameters and fixed‐modes.

The purpose of this work is to controllably synthesize a carbon aerogel with programmable functionally graded performance via a simple and effective strategy.

This work uses polyvinyl alcohol (PVA) via the controllable sol-gel, lyophilization, and carbonization approach to achieve a programmable carbon aerogel. This design has the advantages of low raw material and preparation cost, simple and controllable synthetic process and low carbonization temperature.

The thermal stability and microstructure of PVA aerogel can be controlled by the crosslinking agent content within a certain range. The crosslinking agent content and the carbonization temperature are the key factors for functionally graded programming of carbon aerogels, including microstructure, oxygen-containing functional groups and adsorption performance. The adsorption ratio and adsorption rate of uranium can be controlled by adjusting initial concentration and pH value of the uranium solution. The 2.5%25 carbon aerogel with carbonization temperature of 350 °C has excellent adsorption performance when the initial concentration of uranium solution is 32 ppm at pH 7.5.

As a new type of lightweight nano-porous amorphous carbon material, this carbon aerogel has many excellent properties.

This work presents a simple, low cost and controllable strategy for functionally graded programming of novel carbon aerogel. This carbon aerogel has great potential for application in various fields such as uranium recovery, wastewater treatment, sound absorption and shock absorption.

This paper aims to study the upgradation of the lubricating performance of the renewable base oil , and to study the tribological behavior of graphene oxide (GO) sheets used as lubricating additives in bio-oil for iron/steel contact.

A multifunctional end-face tribometer was used to characterize the friction coefficient and wear loss of the tribosystem under different lubricants.

The experimental results show that GO sheets with small size benefit lubricating effects and the optimal concentration of GO sheets in bio-oil is 0.4-0.6 per cent, which can form a complete lubricating film on the frictional interfaces and obtain a low friction coefficient and wear loss. Higher concentration of GO sheets can result in a significant aggregation of the sheets, reducing the content of the lubricating components in the bio-oil, which results in the increase in friction and wear; at this stage, the main wear pattern was ascribed to adhesive wear.

These results show a promising prospect of improving the tribological performance of renewable base oil with the introduction of GO sheets as additives.

No literature has covered the tribological behaviour of GO sheets in bio-oil. This study contributes to accelerating the application of bio-oil.

Conceptual and empirical research over the past 20 years has moved the social media (SM) literature beyond the embryotic stage to a well-developed academic discipline. As the lead article in the special issue in the Journal of Research in Interactive Marketing on Cutting-Edge Research in Social Media and Interactive Marketing, this review and agenda article has two key goals: (1) to review key SM and interactive marketing research over the past three years and (2) to identify the next wave of high priority challenges and research opportunities.

Given the “cutting-edge” research focus of the special issue, this review and research agenda paper focused on articles published in 25 key marketing journals between January 2021 and March 2024. Initially, the search request was for articles with “social media, social selling, social commerce” located in the article title, author-selected key words and journal-selected keywords. Later, we conducted searches based on terminology from articles presented in the final review. In total, over 1,000 articles were reviewed across the 25 journals, plus additional ones that were cited in those journals that were not on the initial list.

Our review uncovered eight key content areas: (1) data sources, methodology and scale development; (2) emergent SM technologies; (3) artificial intelligence; (4) virtual reality; (5) sales and sales management; (6) consumer welfare; (7) influencer marketing; and (8) social commerce. Table I provides a summer of key articles and research findings for each of the content areas.

As a literature review and research agenda article, this paper is one of the most extensive to date on SM marketing, and particularly with regard to emergent research over the past three years. Recommendations for future research are integrated through the paper and summarized in Figure 2.

Consumer welfare is one of the eight emergent content areas uncovered in the literature review. Specific focus is on SM privacy, misinformation, mental health and misbehavior.

As an optimal microstructure of pipeline steels, acicular ferrite is widely found in steels used in oil and gas pipeline transportation because it possesses both high strength and good toughness. In this paper, the microstructure of acicular ferrite and its continuous cooling transformation (CCT) diagrams of six steels with different carbon and alloy additions have been studied by using dilatometry, optical metallography. And the effects of different hot deformation processes on the CCT diagrams and microstructures have also been studied. Furthermore, the effects of microalloyed elements and hot deformation on continuous cooling transformation have been discussed. The results show that lower carbon content and alloy additions such as Mn, Nb, Ti, Mo, Ni and/or Cu in steels will promote the formation of acicular ferrite. The hot deformation promotes the acicular ferrite transformation and refines the microstructures of final products.

Demonetization and pandemic-related restrictions in India propelled the usage of mobile payments (M-payments). The culture of online smartphone transactions is expected to rise over the coming years, even after things return to normal. This study aims to unveil the factors that escalate the satisfaction levels of M-payment users and eventually stimulate them to continue using M-payments for their daily activities.

This study evaluated the intention to continue using M-payments for 710 users utilizing structural equation modeling and augmenting the technology acceptance model (TAM) as well as the expectation confirmation model (ECM). Mediation and moderation analysis examined the proposed model's direct and indirect relationships.

The findings unveil that perceived value co-creation participation, service quality and cognitive processing magnify user satisfaction, significantly escalating M-payment continuance usage intention. Perceived value co-creation participation and user satisfaction with M-payment partially mediate the linkage among the constructs. Furthermore, perceived usefulness strengthens the link, while perceived severity of security threats weakens the linkage between user satisfaction with M-payment and continuance usage intention.

The study's findings could benefit M-payment service providers, users, policymakers and the telecom industry to strengthen India's digital payment framework.

The perceived value co-creation participation and cognitive processing domain have not garnered much attention in the M-payment literature. The study strives to comprehend these constructs by widening the purview of TAM and ECM models. It also measures the moderating role of perceived severity of security threats and perceived usefulness to unfurl potential linkages between the identified constructs.

This paper aims to explore whether or not and how brand community supportive climates (information- versus emotion-supportive climates) have an impact on consumer-to-consumer helping behavior.

A survey of users of cell phone brand communities was conducted, and data from 413 participants were used to validate the hypotheses of this study.

Results indicated that emotion- and information-supportive climates enhance consumer-to-consumer helping behavior through consumer–community relationships (i.e. brand community identification and brand community commitment).

To enhance the external validity of this research, future studies could investigate other settings (e.g. social media-based brand communities and brands of other product types) in countries with different religious beliefs.

Marketers should create an environment where consumers feel informationally and emotionally supported within the brand community, thereby enabling the former to enhance their relationships with their brand communities and ultimately increase consumers' helping behavior.

By dividing the supportive climate into two parts, the current study enriched the literature on community climate. Moreover, the authors complemented and expanded the literature on consumer helping behavior.

In the context of China’s efforts to build world-class enterprises through mixed-ownership reform, this study aims to build an agency theory framework to analyze the differential relation between ownership structure and firm performance in majority versus minority state-owned enterprises (SOEs). It also evaluates the differential influence that political connectedness has on firm performance in the two types of SOEs.

Using a panel data set of Chinese state-controlled mixed-ownership enterprises covering the period 2010–2019, this paper uses ordinary least squares, random-effects, fixed-effects and three stage least squares regression analysis to study the differential impact of ownership structure and political connectedness on firm performance in majority versus minority SOEs.

In minority SOEs, firm performance is positively related to the ownership share of the largest private shareholder and state ownership positively moderates this relation. Furthermore, minority SOEs with a politically connected chairman perform worse than those with a politically connected chairman. In majority SOEs, there is no relation between the ownership share of the largest private shareholder and firm performance. In addition, majority SOEs with a politically connected chairman perform similar to those without a politically connected chairman.

The theoretical framework demonstrates that agency problems are substantially different in minority versus majority SOEs and that this influences how changes in ownership structure and in the type of chairman that is assigned affect firm performance. The empirical analysis confirms these predictions.