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Previously, the effect of pore-forming agents on the properties of pore size and morphology was studied. In this paper, we determine the optimal combination of parameters by tensile strength and perform tribological tests with optimal combination of parameters.

In this paper, porous polyimide (PI) materials were fabricated using vacuum hot molding technology. The orthogonal experiment was designed to test the mechanical properties of porous PI materials with the process parameters and the content of pore-forming agent as the changing factors. The porous PI oil-bearing materials were obtained by vacuum immersion, and tribological test were carried out.

The results showed that porous PI oil-bearing materials are suitable for low-speed and low-load conditions. The actual value of the friction coefficient basically match with the theoretical value of the regression analysis, and the errors of the friction coefficient are within 10% and 3%, respectively, which proves that the method used in the study is feasible for the friction coefficient prediction.

In this paper, we have produced a new porous oil-bearing material with good tribological properties. This study can effectively predict the friction coefficient of PI porous material.

This paper aims to investigate the tribological properties of polytetrafluoroethylene (PTFE) composites modified by nano-serpentine and nano-lanthanum oxide in a seawater environment.

In this paper, seven PTFE composites were prepared by unified design method and vacuum thermoforming method, and their hardness, water absorption and tribological properties were measured under seawater environment. The modification effects and thermal stability of the materials were analyzed by Fourier transform infrared spectroscopy, thermal gravimetry and differential scanning calorimetry. This paper analyzed the wear mechanism of PTFE composites by scanning electron microscopy and energy spectroscopy.

The results showed that the hardness of the PTFE composites were all improved, but the water absorption was increased with the increase of additives. The modification of nano-serpentine was successful and the thermal stability of PTFE composites was better. The lowest coefficient and minimum wear rate are 0.0267 and 8.67 × 10⁻⁵ · mm³ · (N · m)⁻¹ respectively, which is 34.9% and 76% less than the pure PTFE.

The analysis showed that the wear mechanism of PTFE composites was abrasive wear and a small amount of adhesive wear, and when the additive content was appropriate, it easily formed a transfer film on the surface mating parts.

The purpose of this study is to improve the dispersion of nanoserpentine modified with OA, KH550 and KH550/oleic acid in lubricating oil. The main aims are to analyze the influence of the dispersion and stability of nanoserpentine modified by different modifiers on the friction properties of lubricating oil.

The nanoserpentine particles obtained by ball-milling were modified by silane coupling agent KH550, OA and KH550/OA, respectively. The dispersity and stability of nanoserpentine in base lubricating oil were characterized by the absorbance value method, centrifuge precipitation rate method and static observation method. The MMU-5G screen display friction and wear tester was used to evaluate the tribological properties of C45E4/C45E4 friction pairs in corresponding lubricating oils. The surface morphology of the friction pairs was observed by scanning electron microscopy and energy dispersive spectroscopy.

The results showed that the dispersity and stability of nanoserpentine particles in lubricating oil were best modified by OA, followed by the KH550/OA and finally, the KH550. Nanoserpentine particles modified with oleic acid showed optimum tribological properties as lubricant additives.

This study can improve the dispersion stability of nanoserpentine particles in lubricating oil, increasing the antiwear and antifriction performance of lubricating oil, which has great significance in economic and military aspects.

The content of pore-foaming agent directly affects pore characteristics and oil-absorption properties of polyimide (PI) porous materials, which further influence the tribological performance of PI pore material. This research paper aims to discuss these issues.

Thermal vacuum molding technology was adopted to prepare PI porous material with different structures by changing the content of the pore-forming agent to control pore size and porosity of the PI material. PI oil-bearing materials were obtained by vacuum oil immersion. The tribological experiments of PI oil-bearing materials were conducted on the CETR friction and wear testing machine.

The study results showed that PI porous material with a specific structure can be obtained by controlling the content of a pore-forming agent. In a certain range, with the increase in the content of the pore-forming agent, the average pore size and porosity increased, also the oil content increased, which means that the friction coefficient and wear rate decreased to a very large extent, and antifriction and wear resistant properties of the PI porous materials greatly improved. When the content of the pore-forming agent exceeds 8 per cent, the wear rate and friction coefficient of the PI porous materials began to increase.

Because the complexity of the tribological system consists of lubricating oil, porous material and friction pair, the physical understanding of the mechanism of this process remains limited. Therefore, the present research was undertaken to identify the phenomena involved, which will provide practical guidance for the tribological application in the field of bearing parts.

Based on social cognitive theory, this study aims to explore the effect of authentic leadership on employee green creativity by studying the mediating role of reflection and rumination and the moderating role of psychological capital.

This study used experience sampling methodology to test hypothesis. Specifically, this study applied two-level path analysis to analyze 1,290 observations from 129 employees.

The results show that authentic leadership positively influences reflection but negatively influences rumination, which in turn impact employees’ green creativity. Psychological capital positively moderates the effects of authentic leadership on reflection and negatively moderates the effects of authentic leadership on rumination. Furthermore, psychological capital moderates the linkages between authentic leadership, self-reflection and employee green creativity.

Organizations should make efforts in promoting authentic leadership and recruiting employees who possess high psychological capital. Moreover, managers can make effective efforts to stimulate employees’ reflection and mitigate rumination, thereby facilitating organizational sustainable development.

In investigating green issues related to employees’ daily cognitive processes, this study focuses on within-personal reaction mechanism to authentic leadership, concerning the moderating effect of individual psychological capital.

Prior research has suggested that abusive supervision has negative impacts on various work outcomes. However, little attention has been paid to the relationship between abusive supervision and employees’ safety behaviour. The purpose of this study is, therefore, to address these limitations by developing and testing a theoretically based conceptual model that explicitly considers the underlying mechanism and boundary condition of the relationship between abusive supervision and safety behaviour of underground coal miners in China.

At Time 1, the authors conducted a survey of 630 employees to assess their supervisors’ abusive leadership behaviours, their own power distance beliefs and their self-reflection. At Time 2, the authros sent questionnaires to the leaders and invited them to evaluate employees’ safety behaviour in the workplace. After cleaning the survey data, the authors tested our model using a multi-level analysis on a sample (n = 458) of underground miners across 96 coal mining sites in China.

The authors propose that abusive supervision decreases employees’ safety compliance/participation by reducing reflection but strengthening rumination. The authors further find that the linkage from abusive supervision to reflection/rumination to safety compliance/participation is affected by power distance.

To the best of the authors’ knowledge, This is one of the first empirical studies to investigate the mediating effects of a deep cognitive processing variable – namely, self-reflection – and the moderating effects of power distance on the relationship between abusive supervision and safety behaviour.

Based on social information processing (SIP) theory, this study explores the cross-level effect of high-involvement work practices (HIWPs) on employee innovative behavior by studying the mediating role of self-reflection/rumination and the moderating role of transactive memory system (TMS).

This study collects data from 452 employees and their direct supervisors in 94 work units, and tests a cross-level moderated mediation model using multilevel path analysis.

The results suggest that HIWPs significantly contribute to employee innovative behavior. Both self-reflection and self-rumination mediate the above relationship. TMS not only positively moderates the relationship between HIWPs and self-reflection, but also reinforces the linkage of HIWPs. →self-reflection→employee innovative behavior. Furthermore, TMS negatively moderates the relationship between HIWPs and self-rumination, and attenuates the mediating effect of self-rumination.

The study suggests that enterprises should invest more in promoting HIWPs and TMS in the workplace. Furthermore, managers should provide employees training programs to enhance their self-reflection, as well as lower self-rumination, in order to facilitate employee innovative behavior.

This research identifies self-reflection and self-rumination as key mediators that link HIWPs to employee innovative behavior and reveals the moderating role of TMS in the process.

The purpose of this paper is to investigate the government roles in cloud computing assimilation along two dimensions: government regulation and government support.

A research model was developed to depict the dual roles of government regulation and government support in cloud computing assimilation as well as the mediating effect of top management support (TMS). Using survey data collected from 376 Chinese firms that have already adopted cloud services, the authors tested the research model.

The impacts of both government regulation and government support on cloud computing assimilation are partially mediated by TMS. Government support exerts stronger impacts on TMS than government regulation.

This study extends the current information systems literature by highlighting the specific mechanisms through which governments influence firms’ assimilation of cloud computing.

Governments in developing countries could actively allocate funds or enact policies to effectively encourage cloud computing assimilation.

This study would complement previous findings about government regulation, and develop a more holistic understanding about the dual roles of governments in information technology innovation assimilation.

The purpose of this paper is to provide a balanced and nuanced understanding of the relationship between high-performance work systems (HPWS) and employee thriving at work by aiming to consider the “dark-side” of HPWS and to uncover the “black box.”

This research draws from data from 377 employees nested in 77 work teams and tests a multilevel moderated mediation model using multilevel path analysis.

The findings indicate that employees appraise HPWS as both a challenge and a hindrance simultaneously. The challenge appraisal associated with HPWS positively influences employees' thriving at work whereas hindrance appraisal of HPWS negatively influences thriving experience. The results also support the hypothesized relationships in which servant leadership moderates the indirect effect of HPWS on employee thriving via challenge and hindrance appraisals accordingly.

This research demonstrates both positive and negative sides of HPWS as evaluated by employees in relation to an important employee outcome of thriving at work. It enriches the strategic HRM literature by identifying the “black box” of HPWS-employee outcomes and associated boundary condition from the theoretical perspective of cognitive appraisals.

The purpose of this paper is to explore the cross-level effect of servant leadership on employee innovative behavior by studying the mediating role of thriving at work and the moderating role of team reflexivity.

This research collected data from 199 dyads of employees and their direct supervisors in 55 work units, and tested a cross-level moderated mediation model using multilevel path analysis.

The findings suggest that thriving at work mediates the relationship between servant leadership and innovative behavior. The results also show that team reflexivity positively moderates the relationship between servant leadership and thriving at work and the mediating effect of thriving at work.

The empirical findings suggest that organizations should make efforts to promote servant leadership and encourage team reflexivity. Moreover, managers should make efforts to stimulate employees’ thriving at work, thereby facilitating employee and organizational development.

This research identifies thriving at work as a key mediator that links servant leadership to innovative behavior and reveals the role of team reflexivity in strengthening the effect of servant leadership on employee innovative behavior.