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With respect to severe working conditions such as heavy load and impact, this paper aims to investigate the friction reduction and anti-wear performance of kaolin and molybdenum dialkyl dithiophosphate (MoDDP) composite lubricant additives to improve the lubrication effect of a single additive.

A four-ball friction test was carried out to determine the optimal concentration of kaolin and organic molybdenum additives and the tribological properties of the kaolin/MoDDP composite lubricant additives. A ring block test of composite lubricant additives was designed to investigate its lubrication performance under the severe working conditions of low speed, heavy load and impact.

The results showed that the optimal addition mass fractions of kaolin and MoDDP were 4.0 and 1.5 Wt.%, respectively, when kaolin and MoDDP were used as single lubricant additives. Compared with the single additive, the 4.0 Wt.% kaolin/1.5 Wt.% MoDDP composite lubricant additive showed excellent friction reduction and anti-wear effects under heavy load and impact conditions. Physicochemical analysis of the wear surface revealed that the lamellar kaolin additive and MoDDP had excellent synergistic effects, and the friction process promoted the generation of lubricant films containing a chemically reactive layer of MoS₂, MoO₂, FeS₂ and Fe₂O₃ and a physically adsorbent layer containing SiO₂ and Al₂O₃, which play important roles in anti-wear and friction reduction.

The excellent friction reduction and anti-wear effects of lamellar silicate minerals and the excellent antioxidant properties and good synergistic effects of molybdenum were comprehensively used to develop the composite additives with great lubricating properties.

The primary aim of this paper is to concurrently use the data types to enhance econometric analysis in the housing market in developing countries, particularly Namibia.

Scholarly discussions on econometric analysis in the housing market in sub-Saharan Africa suggest that the inadequacy of time series data has impeded studies of such nature in the region. Hence, this paper aims to comparatively analyse the impact of economic fundamentals on house prices in Namibia using real and interpolated data from 1990 to 2021 supported by the ARDL model.

It was discovered that in all the three types of data house prices were affected by fundamentals except real GDP in the long term. It was also noted that there were not much significant variations between the real data and the interpolated data frequencies. However, the results of the annual data and the semi-annual interpolated data were more analogously comparable to the quarterly interpolated data

It is suggested that the adoption of interpolated data frequency type should be based on the statistical significance of the result. In addition, the need to monitor the nexus of the housing market and fundamentals is necessary for stable and sustainable housing market for enhanced policy direction and prudent property investment decision.

The study pioneer to concurrently use the data types to enhance econometric analysis in the housing market in developing countries.

The purpose of this paper is to study the corrosion behavior of Q235 steel in saturated acidic red and yellow soils.

The corrosion behavior of Q235 steel in saturated red and yellow soils was compared by weight-loss, SEM/EDS, 3D ultra-depth microscopy and electrochemical measurements.

R_p of the steel gradually increases and i_corr gradually decreases in both the red and yellow soils with time. The R_p of the steel in the red soil is lower, but its i_corr is higher than that in the yellow soil. The uniform corrosion rate, diameter and density of the corrosion pit on the steel surface in the red soil are greater than those in the yellow soil. Lower pH, higher contents of corrosive anions and high-valence Fe oxides in the red soil are responsible for its higher corrosion rates and local corrosion susceptibility.

This paper investigates the difference in corrosion behavior of carbon steel in saturated acidic red and yellow soils, which can help to understand the mechanism of soil corrosion.

This study aims to examine the relationship between managerial ability and innovation efficiency, the mediating effect of digital transformation and the moderating effect of internal control.

This study collected A-share manufacturing listed companies in China from 2008 to 2019 and analyzed the data by means of multiple regression analysis, mediating effect test, moderating effect test and heterogeneity test. Finally, the authors conducted robustness test by remeasuring key variables and adding control variables.

The empirical results show that the higher managerial ability can improve innovation efficiency, internal control has a positive moderating effect and digital transformation plays a partial mediating effect on the relationship between managerial ability and innovation efficiency. Specially, it is found that the mediating effect of digital transformation is not significant in non-state-owned firms.

This study suggests that it is necessary to focus on the managerial ability in terms of both cultivation and supervision, to further deepen the digital transformation from the aspects of firms, government and society, especially to support the digital transformation of non-state-owned firms, and to make efforts to improve the corporate governance mechanism and internal control system, so as to better comprehensively realize the improvement of enterprise innovation efficiency.

Based on the mediating effect analysis of digital transformation and the moderating effect analysis of internal control, this study explores the role of managerial ability on innovation efficiency from a new perspective, expanding the related theoretical framework and research boundaries.

This paper aims to investigate the motivational drivers for knowledge sharing (KS) through the application of mobile social networking (MSN) and their influence on employee productivity in the Malaysian construction industry.

The data was collected by distributing a self-administered questionnaire among employees working in the construction industry. A total of 250 questionnaires were collected and analysed using partial least squares structural equation modeling. This study used a variety of analysis methodologies including correlation analysis, reliability and validity testing, as well as a structural model in evaluating the relationships between KS, motivational factors and influence on productivity.

The empirical results of this study reveal that utilitarian motivation is positively related to internal and external KS. Similarly, internal and external KS have a positive influence on productivity, while internal and external hedonic motivation does not show any significant relationship with productivity.

Considering the paucity of evidence regarding the determinants of KS motivational drives on employee productivity in the Malaysian construction industry, this study enriches the social cognitive theory-based literature on KS.

This study provides some insights to the players in the construction industry in implementing the most appropriate KS promotion strategies that could potentially influence employee productivity. Organisations in the construction industry that place great emphasis on utilitarian motivation including competency, reward and incentives are more likely to have a better influence on KS and, in turn, positively impact employee productivity.

This study meaningfully contributes to enhancing the understanding of the motivational drivers for sharing knowledge on MSN and its influence on productivity. The findings of this study potentially assist construction practitioners in developing a holistic blueprint for managing their KS towards improving the overall productivity of their employees.

The aim was to investigate the effect of Cr₃C₂ mass fraction the high-temperature tribological performance of laser cladded WC-10Co₄Cr coating, in which the Cr₃C₂ played the role in enhancing wear resistance.

The WC-10Co₄Cr-xCr₃C₂ (x = 5%, 10% and 15%) were prepared on H13 steel using laser cladding, and their coefficients of friction and wear rates at 500°C were investigated using a ball-on-disc wear tester.

The WC-10Co4Cr-xCr₃C₂ powders are composed of WC, Co₃W₃C, CoCr and Cr₃C₂ phases, and the defects such as pores and cracks are reduced by the addition of Cr₃C₂. The coefficient of friction and wear rats of WC-10Co4Cr-xCr₃C₂ coatings are decreased with the Cr₃C₂ mass fraction, showing that the addition of Cr₃C₂ significantly enhances the tribological properties of WC-10Co₄Cr coating. The wear mechanism is adhesive wear and oxidation wear, and the Cr₃C₂ plays the roles of friction reduction and wear resistance, which provides valuable insights into optimizing the performance of WC-10Co₄Cr coating.

The Cr₃C₂ was first added into the laser cladded WC-10Co₄Cr coating, which improved its high-temperature tribological performance.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2024-0471/

The study aims to investigate the association between environmental reporting (ER) and firm performance and whether board independence plays any role in this relationship in the context of Bangladesh, an emerging economy.

The study has used a sample of 289 firm-years derived from the listed manufacturing companies of Bangladesh for the years 2018–2023. To measure ER, content analysis has been performed. Financial performance has been calculated using both accounting-based (ROA, ROE and EPS) and market-based (Tobin’s Q) performance measures. Two-step system generalized method of moments method has been used to test the hypotheses.

The study has found a very low level of ER practice by the sample firms. The regression results show a positive and significant impact of ER on both accounting-based and market-based performance measures. In addition, existence of greater board independence is found to positively affect this relationship between ER and performance.

The findings of the study emphasize the importance of ER in improving performance which will have significant implications for the practitioners. Besides, the importance of greater board independence in enhancing the capability of ER to improve performance will provide valuable insights to the policymakers and regulators.

To the best of the authors’ knowledge, this is the first study to investigate the role of an effective corporate mechanism, board independence, in improving the relationship between ER and performance in the context of an environmentally sensitive country such as Bangladesh.

A 3D finite element (FE) model based on the double ellipsoidal heat source was developed to investigate the evolution of temperature and stress fields during the multilayer and multi-pass wire and arc additive manufacturing (WAAM) process. This paper aims to investigate the evolution of temperature and stress fields during the multilayer and multi-pass wire and arc additive manufacturing (WAAM) process by developing a 3D finite element (FE) model based on the double ellipsoidal heat source.

Experimental thermal cycle curves and residual stresses were obtained by thermocouples and X-ray diffraction, respectively. The validity of the model was verified by the corresponding experimental results.

The deposition process of the upper pass led to the partial remelting of the lower deposited pass. The thermal process of the current-deposited pass alleviated the stress concentration in the previous-formed passes. A more uniform temperature distribution could be obtained by using the reciprocating deposition path. Compared to the reciprocating deposition path, the peak values of the transverse and longitudinal tensile residual stresses of the deposited sample under the unidirectional deposition path were reduced by 15 MPa and increased by 13 MPa, respectively. The heat conduction in the deposited passes could be improved by extending the inter-pass cooling time appropriately. With an increase in the inter-pass cooling time, the longitudinal residual stress in the middle region of sample along longitudinal and transverse directions showed increase and decrease–increase trends, respectively, while the transverse residual stress exhibited decrease trend.

This study enhances the understanding of temperature and stress fields evolution during the multilayer and multi-pass cold metal transfer-WAAM processes of magnesium alloy and provides the reference for parameter optimization.

Political factors play a crucial role in China's initial public offering (IPO) market due to its distinctive institutional context (i.e. “economic decentralization” and “political centralization”). Given the significant level of IPO underpricing in China, we examine the impact of local political uncertainty (measured by prefecture-level city official turnover rate) on IPO underpricing.

Using 2,259 IPOs of A-share listed companies from 2001 to 2019, we employ a structural equation model (SEM) to examine the channel (voluntarily lower the issuance price vs aftermarket trading) through which political uncertainty affects IPO underpricing. We check the robustness of the results using bootstrap tests, adopting alternative proxies for political uncertainty and IPO underpricing and employing subsample analysis.

Local official turnover-induced political uncertainty increases IPO underpricing by IPO firms voluntarily reducing the issuance price rather than by affecting investor sentiment in aftermarket trading. These relations are stronger in firms with pre-IPO political connections. The effect of political uncertainty on IPO underpricing is also contingent upon the industry and the growth phase of an IPO firm, more pronounced in politically sensitive industries and firms listed on the growth enterprise market board.

Local government officials in China usually have a short tenure and Chinese firms witness significantly severe IPO underpricing. By introducing the SEM model in studying China IPO underpricing, this study identifies the channel through which local government official turnover to political uncertainty on IPO underpricing.

The purpose of this paper is to explore how emerging market firms (EMFs), in the face of intense international competition within global value chains (GVCs), continuously accumulate the knowledge and capabilities needed to support leapfrog upgrading. Based on this, this paper aims to construct a process model of the dynamic evolution of EMFs’ control over GVC core activities.

This paper conducts a longitudinal case study of Ninestar Corporation, a leading company in the Chinese printer industry, to investigate its leapfrog upgrading practices. From the perspective of dynamic capabilities theory, the study explores the dynamic processes and intrinsic mechanisms through which EMFs achieve the evolution of their control over GVC core activities.

It is revealed that the dual-dimensional expansion of controlling the core activities of GVC from vertical functional architecture to horizontal product architecture is the pathway for manufacturing enterprises in emerging economies to achieve leapfrogging upgrades. It is also found that the dynamic capabilities of EMFs undergo iterative evolution during the upgrading process. The self-reinforcing logic and the path-creation logic of dynamic capabilities are the internal mechanisms for controlling GVC core activities to achieve the breakthrough in both the vertical functional division chain and the horizontal product division chain.

This paper provides an insightful case for how EMFs can achieve leapfrog upgrading in the new normal of global trade patterns. It explores how these firms can gain control over GVC core activities through the evolution of dynamic capabilities. The research findings extend the boundaries of the theory of firm upgrading.