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This paper aims to study the effects of MnO₂ on the ZnO–Bi₂O₃-based varistor prepared via flash sintering (FS)

MnO₂-doped ZnO–Bi₂O₃-based varistors were successfully prepared by the FS with a step-wise increase of the .current in 60 s at the furnace temperature <750°C under the direct current electric field of 300 V cm⁻¹. The FS process, microstructure and the electrical performance of ZnO–Bi₂O₃-based varistors were systematically investigated.

The doping of MnO₂ significantly decreased the onset temperature of FS and improved the electrical performance of FS ZnO varistor ceramic. The sample with 0.5 mol% MnO₂ doping shows the highest improvement, with the nonlinear coefficient of 18, the leakage current of 16.82 µA, the threshold voltage of 459 V/mm and the dielectric constant of 1,221 at 1 kHz.

FS is a wonderful technology to enhance ZnO varistors for its low energy consumption, and a short sintering time can reduce grain growth and inhabit Bi₂O₃ volatilize, yet few research studies work on that. In this research, the authors analyzed the FS process and improved the electrical characteristics through MnO₂ doping.

The purpose of this paper is to obtain liquid acrylate oligomers containing carboxyl groups as excellent toughening agents for epoxy resins.

Liquid acrylate oligomers containing carboxyl groups were synthesised by the solution polymerisation of butyl acrylate (BA), acrylic acid (AA) and acrylonitrile (AN) as monomers. The liquid acrylate oligomers were used as the toughening agents for epoxy resins. The chemical structure of the oligomers was characterised by ¹³C nuclear magnetic resonance (NMR) spectroscope. The morphology of modified epoxy networks was analysed by scanning electron microscope (SEM). The mechanical and thermodynamic properties were measured by universal testing machine and dynamic mechanical analyser (DMA).

The results show that AA and oligomer concentrations have great influence on the morphology, mechanical and thermodynamic properties of the modified epoxy networks. When the 10 wt percent oligomer containing BA and AN and AA in the ratio of 75/20/5 is used to modify the epoxy resin, the increase in impact strength of the modified epoxy network is 291.5 percent over the unmodified epoxy network due to addition of the oligomers without a sacrifice in heat‐resistance properties. Fracture surface analysis by SEM indicates the presence of a two‐phase microstructure.

The modified epoxy networks can be used as high performance materials such as adhesives, sealants and matrices of composites.

The liquid acrylate oligomers containing carboxyl and nitrile groups which were synthesised with BA, AA and AN as monomers by the solution polymerisation are novel and can greatly increase the toughness of epoxy resins without loss of thermal resistance.

This study aims to examine the determinants of the female representations on Chinese listed firm’s boards. This study also investigates the effect of gender diversity on corporate social responsibility activities.

The Tobit regression model is used because the data is censored and using ordinary least square regression can give spurious results. For robust check, the authors also used Heckman’s (1979) two-stage self-selection model to remove the sample self-selection bias.

The authors find that the female representations on the corporate board are positively associated with firm age, firm performance, corporate governance, family ownership, institutional ownership and managerial ownership while negatively related to firm size and state ownership. This study also incorporates predictors of the critical mass of women on the Chinese listed firm’s board. The study also tests the female-led hypothesis and concludes that the female representation increases in firms with female chief executive officer (CEO) or female chairpersons. The Chinese listed firms with gender-diverse board are socially responsible.

The importance of diversity in corporate boards has been demonstrated in light of the agency theory and the resource dependence framework. The results contribute to the previous literature by documenting the determinants of female representations on board, robust by alternative measures of gender diversity, firm size, corporate governance and estimation techniques.

The economic significance of gender diversity stirred the firms to increase female representation. The policymakers can understand the reasons for female underrepresentation in Chinese boards and can reform the regulation to enhance governance quality, non-state ownership and risk aversion among the listed firms.

This study contributes to the literature by providing empirical evidence on the key predictor of the world’s largest emerging economy, specifically the study focuses on the firm specific determinants, different governance attributes, ownership structure and firm risk measures. This study also seeks to answer if the presence of a female in the Chairperson or CEO position encourages the firms to hire more female directors or not?

Outlines the ideas incorporated in “development economics” and criticizes the lack of distinction made by some writers between development and economic growth. Asks whether underdeveloped countries really need a different economic theory from Western Europe and suggests that growth (in gross national product) and development (i.e. structural change) are actually complementary processes. Reviews various theories on the causes of underdevelopment (e.g. market failure, government failure) and strategies to cure it (e.g. government intervention, private initiative, market mechanism); and cites some examples of successful positive intervention.

In order to obtain functionalized core-shell nanoparticles (CSNPs) as excellent toughening agents for epoxy resins. The paper aims to discuss these issues.

Functionalized CSNPs containing epoxy groups on the surface were synthesized by emulsion polymerization with butyl acrylate as the core and methyl methacrylate copolymerizing with glycidyl methacrylate (GMA) as the shell. CSNPs were used as toughening agents for epoxy resins and their chemical structure was characterized by FT-IR. The morphology of modified epoxy networks (MEPN) was analyzed by SEM and TEM. Both the mechanical properties and thermodynamic properties were studied.

The results show that nearly spherical CSNPs with the particle size of 50-100 nm are obtained. A certain amount of CSNPs are uniformly dispersed in epoxy resins by the grinding method and the MEPN shows the ductile fracture feature. The miscibility between CSNPs and epoxy matrix increases with the increase of GMA concentration which makes more bonds form between them. Epoxy resins toughened with 10 wt% CSNPs containing 10 wt% GMA show the best mechanical properties and the increase in tensile strength and impact strength of the MEPN is 13.5 and 59.7 percent, respectively, over the unmodified epoxy networks. And the improvement in impact strength is not accompanied with loss of thermal resistance.

The MEPN can be used as high-performance materials such as adhesives, sealants and matrixes of composites.

The functionalized CSNPs are novel and it can greatly increase the toughness of epoxy resins without loss of thermal resistance.

As academic social Q&A networking websites become more popular, scholars are increasingly using them to meet their information needs by asking academic questions. However, compared with other types of social media, scholars are less active on these sites, resulting in a lower response quantity for some questions. This paper explores the factors that help explain how to ask questions that generate more responses and examines the impact of different disciplines on response quantity.

The study examines 1,968 questions in five disciplines on the academic social Q&A platform ResearchGate Q&A and explores how the linguistic characteristics of these questions affect the number of responses. It uses a range of methods to statistically analyze the relationship between these linguistic characteristics and the number of responses, and conducts comparisons between disciplines.

The findings indicate that some linguistic characteristics, such as sadness, positive emotion and second-person pronouns, have a positive effect on response quantity; conversely, a high level of function words and first-person pronouns has a negative effect. However, the impacts of these linguistic characteristics vary across disciplines.

This study provides support for academic social Q&A platforms to assist scholars in asking richer questions that are likely to generate more answers across disciplines, thereby promoting improved academic communication among scholars.

This study aims to focus on the clothing recycling supply chain and aims to provide optimal decisions and managerial insights into supply chain strategies, thereby facilitating the sustainable development of the clothing industry.

Based on previous single- and dual-channel studies, game theory was employed to analyze multiple recycling channels. Concurrently, clothing consumer types were integrated into the analytical models to observe their impact on supply chain strategies. Three market scenarios were modeled for comparative analysis, and numerical experiments were conducted.

The intervention of fashion retailers in the clothing recycling market has intensified competition across the entire market. The proportions of various consumer types, their preferences for online platforms and their preference for the retailer’s channel influence the optimal decisions and profits of supply chain members. The diversity of recycling channels may enhance the recycling volume of clothes; however, it should meet certain conditions.

This study extends the existing theory from a channel dimension by exploring multiple channels. Furthermore, by investigating the classifications of clothing consumers and their influence on supply chain strategies, the theory is enhanced from the consumer perspective.

The purpose of this study is to assess the validity of the psychological safety (PS), psychological empowerment (PE), intrapreneurial behaviour (IB) and individual performance (IP) construct measurements originally developed in Western individualistic cultures.

Proportionate stratified systematic sampling was used among the production/operations middle managers in Nigerian medium enterprises (MEs), resulting in 355 valid responses. The measurements were analysed through internal consistency analysis, content, convergent and discriminant validity analysis.

The result shows that all four construct measurements are suitable and appropriate to gauge the respective constructs in collectivistic cultures such as Nigeria.

Cross-sectional self-reported data were used to analyse the result of this study, which may lead to common method variance.

Organizations, especially MEs, can use the validated measurements of this study to enhance work results in the Nigerian context.

Collectivistic cultures can benefit from the widely used measurements of PS, PE, IB and IP despite been originally developed in Western individualistic cultures.

This paper extends the body of knowledge by validating the measurements of PS, PE, IB and IP in collectivistic cultures such as Nigeria. Measurement validation for these constructs is scarce in this context. Thus, this study will provide a consistent and efficient reference for forthcoming studies and improve the credibility and replicability of future research results in collectivistic cultures.

This article’s indented contribution is to provide novel theoretical insights and empirical observations on “who gets what” in the way of incomes, including wages. The article challenges the conventional wisdom about stratification, especially power and status, as an outcome or function of economic distribution. It posits that income distribution is conditional on pre‐existing social stratification expressed in antecedent differences in class, power, status and related factors.

Learning from errors is important for employees, particularly at early stages of their career. The purpose of this paper is to examine the influence of perceived trainer responses to errors on trainee learning from errors in a workplace setting. In Study 1, the authors test a model that examines the associations between perceived trainer responses to errors and trainee learning from errors, which are mediated by affective-motivational adaptivity. In Study 2, the authors further hypothesize that the link between perceived trainer responses and affective-motivational adaptivity is moderated by perceived error climate.

The authors test the hypotheses using data from 213 Swiss apprentices (Study 1) and 1,012 German apprentices (Study 2) receiving dual vocational training.

Study 1 suggests that negative trainer reaction impedes trainee learning from errors by impairing trainees’ affective-motivational adaptability. Trainer tolerance of errors and trainer support following errors were not related to trainee learning from errors. Study 2 indicates that perceived error climate is an important boundary condition that affects the relationship between trainer responses and trainee learning from errors.

This study contributes to research on learning from errors in three ways. First, it enriches the understanding regarding the role of trainers in enhancing learning from errors in organizations. Second, it extends research on learning from errors by investigating the interaction effects between perceived trainer responses and error climate. Third, it refines knowledge about the role of positive affect in learning from errors. Findings of this study also offer practical insights to trainers and managers regarding what they should do to encourage trainee learning from errors.