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This paper aims to study the tribological behavior of the WS2/oil-impregnated porous polyimide (PPI) solid/liquid composite system, in which both PFPE (perfluoropolyether) and SiCH (silahydrocarbons) oils with different hydrocarbon chains were used, respectively. Lubricating mechanism of the composite system was also explored.

The tribological behaviors of the WS2 films against the PPI cylindrical pins before and after immersing oil were evaluated under different loads by a reciprocating-type ball-on-disc tribometer.

The composite system exhibited the low and stable friction coefficient after the running-in stage, and the lubricant oil played a positive effect. It was found that the WS2/PFPE composite system exhibited more excellent lubricating property, although sole SiCH far exceeds PFPE in lubrication. The abnormal phenomenon mainly resulted from the influence of the oil amount. XRD results on the wear track surfaces indicated that PFPE and SiCH oils with different hydrocarbon chains were likely to preferentially adsorb to the edge plane and basal plane of the WS2 crystals, respectively.

In previous studies, liquid lubricants were directly dripped or spin-coated on the solid lubricant surface. Based on its potential advantage in application, the tribological behavior and mechanism of the solid lubricating film/oil-impregnated PPI composite system were investigated in this study.

The aim of this paper was to inhibit the serious corrosion of conventional ionic liquids, a series of new ionic liquids (ILs) containing the triazole functionality, as the anti-corrosion groups were synthesized in this work.

It is well known that nitrogen and sulfur containing organic compounds have been traditionally used as corrosion inhibitors. Among them, triazole derivatives are most often used as corrosion inhibitors. To alleviate the corrosion of the ILs and further improve the anti-wear property, the authors prepared a series of imidazolium ILs modified with the triazole functionality in the present study.

The corrosion behavior of the ILs was evaluated with the iron disk corrosion test and their tribological properties were investigated on an Optimol SRV IV oscillating friction and wear tester at elevated temperatures. The results showed that the ILs with the triazole functionality could effectively reduce the corrosion and exhibit a smaller friction coefficient and wear volume than the unmodified counterpart. The ILs containing the triazole functionality can be used as the single component anti-corrosion base oils even at elevated temperatures.

The results showed that the ILs with the triazole functionality could effectively reduce the corrosion and exhibit a smaller friction coefficient and wear volume than the unmodified counterpart. The ILs containing the triazole functionality can be used as the single component anti-corrosion base oils even at elevated temperatures.

The purpose of this paper is to design the crown‐type phosphate ionic liquid additive which can dissolve in poly(ethylene glycol) (shortened to PEG) completely, and evaluate the tribological properties as additive in PEG for steel/steel contacts.

To improve the solubility and the tribological performance of ionic liquid additive in PEG, the crown‐type phosphate ionic liquid additive was prepared. The tribological properties of the crown‐type phosphate ionic liquid additive in PEG were evaluated at different concentrations and rubbing frequencies on an Optimol SRV oscillating friction and wear tester. The morphology and chemical compounds of the wear scars were analyzed by scanning electron microscope (SEM) and X‐ray photoelectron spectroscopy (XPS).

The experimental results show that the crown‐type phosphate ionic liquid additive applied in based oil exhibits better tribological properties for steel/steel contacts at different loads, concentrations and rubbing frequencies. It could improve the anti‐wear ability and reduce the friction coefficients as the increased concentration. By the SEM and XPS analysis, it is found that there were the effective boundary lubricant films in the worn surface. The boundary films were composed of various tribochemical products, ferric oxide, ferric phosphate and pyrophosphate, together with the absorbed films.

Compared with the poor miscibility of some ionic liquid in PEG, the crown‐type phosphate ionic liquid additive can dissolve in PEG perfectly. It can improve the anti‐wear ability and reduce the friction coefficient of PEG at different concentrations and rubbing frequencies.

The purpose of this paper is to synthesize a novel kind of crown‐type phosphate ionic liquids with better tribological properties for steel/Al system. The anions of crown‐type phosphate ionic liquids contain no F element, which are non‐corrosive to metal.

To improve the tribological properties of ionic liquid lubricants for the extremely difficult system of the steel‐against‐aluminum metal couple, novel crown‐type phosphate ionic liquids were prepared. The tribological properties of the crown‐type phosphate ionic liquids were evaluated at different loads and frequencies on an Optical SRV oscillating friction and wear tester. The morphology and chemical compounds of the wear scars were investigated by scanning electron microscope (SEM) and X‐ray photoelectron spectroscopy (XPS).

Compared with conventional ionic liquids, the novel crown‐type phosphate ionic liquids prepared in the present work exhibit a more excellent anti‐wear ability for steel/Al2024 contact at different loads and frequencies. By the morphological analysis with SEM, less debris was observed in the worn surface lubricated with crown‐type phosphate ionic liquids, though more debris was observed when lubricated with LB106 and LP106. By the XPS analysis, boundary lubrication film composed of aluminum (III) oxide, organometallic compounds, and silicon aluminum phosphate were found in the worn surface. Namely, the tribological behaviors of the crown‐type phosphate ionic liquids could be attributed to their stronger adsorption and tribochemical interactions with the Al alloys.

Because of the higher mean friction coefficients of crown‐type phosphate ionic liquids in the research, researchers are encouraged to modify their structure for better tribological properties.

The crown‐type phosphate ionic liquid exhibited better anti‐wear performance for steel/aluminum contact than the conventional ionic liquids containing F element. This will expand the application of high strength aluminum alloys.

The phosphate ionic liquid is a non‐corrosive liquid and would not cause metal corrosion. Also, the tribological properties of crown‐type phosphate ionic liquid with steel/aluminum contact are better than that of conventional ionic liquids. By the designing of molecular structure, new phosphate ionic liquids will exhibit excellent tribological properties: lower wear volume and lower friction coefficient.

The purpose of this paper is to synthesize a series of cyclophosphazene derivatives with better tribological properties.

To improve the adsorptivity to substrate, a series of cyclophosphazene derivatives substituted with ionic liquids were synthesized. The lubricity characteristics of phosphazene derivatives were evaluated on an Optimol SRV IV oscillating friction and wear tester. Scanning electron microscope and X‐ray photoelectron spectroscope analyses were conducted to examine the morphology and chemical composition of the wear scars and the possible tribochemical changes involved in the friction process.

Alkoxycyclophosphazene derivatives substituted with ionic liquids synthesized in the present work show better antiwear ability and load‐carrying capacity in steel‐steel contacts. The density of ion pairs plays an important role on tribological properties.

The paper deals with only a limited compounds and steel‐steel contacts. The paper works on the subject progressively to explore more combinations for better tribological properties.

All the cyclophosphazene derivatives present better tribological performance and could be used as base oils, such as hard disk surface lubricants.

Ionic liquids are introduced to cyclophosphazene derivatives in this paper. This is a new method to improve the tribological properties of cyclophosphazene derivatives.

The purpose of this paper is to examine the tribological behavior of the synthetic chlorine‐ and fluorine‐containing silicon oil as an aerospace lubricant.

The chlorinated‐phenyl and methyl terminated silicone oil (CPSO), chlorinated‐phenyl and trifluorinated‐propyl with methyl terminated silicone oil (FCPSO) were prepared. Their physical properties such as saturated vapor pressure and the evaporation weight loss were evaluated. The tribological properties of the silicon oils under moderate load were investigated with an Optimol SRV oscillating friction and wear tester, as well as Four‐ball friction and wear tester according to the standard method of ASTM D 4172 under higher load. The elemental composition generated on steel ball surface were analyzed on a scanning electron microscope with a Kevex energy dispersive X‐ray analyzer attachment (SEM/EDS), and the chemical nature of elements on worn surface lubricated with FCPSO were studied by X‐ray photoelectron spectrometer (XPS).

It is found that the CPSO and FCPSO show good tribological behavior for steel/CuSn alloy tribological pairs and are superior to hosphazene (X‐1P) and perfluoropolyether in terms of friction‐reduction ability and anti‐wear performance. The anti‐wear performance of FCPSO as lubricants for steel‐steel contacts is superior to CPSO. The EDS results showed existence of F and Si on the worn surface with lubrication of FCPSO, while XPS results indicated the occurrence of tribochemical reaction of FCPSO with friction pair during sliding process with the formation of FeCl₂, FeF₂ and the absorption silicon oil films on the lubricated metal surface.

The results substantiate that chemical reactive elemental such as chlorine or fluorine, which is substituted into silicon oil, helps to improve the anti‐wear and load‐carrying capacity of the liquid lubricant. So the excellent thermal stability, low‐temperature fluidity, very low‐saturated vapor pressure and excellent lubricity for steel/CuSn alloy of the silicon oil of FCPSO and CPSO make it an attractive alternative to conventional liquid lubricant for space mechanism.

The concept of entrepreneurship in platform enterprises has evolved and developed. The purpose of this paper is to explore how entrepreneurship in platform enterprises can be transformed into the sustainable innovation capability of enterprises based on knowledge integration.

This study adopts a questionnaire survey. The research samples are mainly from well-known domestic platform enterprises, EMBA students and professional online websites, 389 valid questionnaires were collected.

The results show that entrepreneurship has a positive impact on the sustainable innovation capability of platform enterprises, knowledge integration plays a partial mediating role between entrepreneurship and sustainable innovation capability of platform enterprises. Shared leadership plays a moderating role between entrepreneurship and knowledge integration and knowledge-sharing atmosphere plays a moderating role between knowledge integration and sustainable innovation capability of platform enterprises.

This paper emphasizes the key role of entrepreneurship in platform enterprises on the sustainable innovation capability and discusses the realization path of the sustainable innovation capability of platform enterprises from the perspective of knowledge integration, which is of great significance for developing the research system of entrepreneurship and promoting the construction of sustainable innovation capability of platform enterprises.

The internet-based transition is the major trend for Chinese organizations with increasing demands imposed on their organization and management. As the organizational structures gradually improve flexibility, employees desire respect and development to a greater degree, which has given rise to a new leadership model-integrative leadership. This paper aims to investigate the impact of integrative leadership on employee’s innovation performance through a multilevel analysis.

This paper proposes the two situational factors employee psychological empowerment and human resource flexibility as the mediating factors impact the relationship between integrative leadership and employee innovation performance. Valid questionnaires were collected from 619 employees from 135 leader groups of High-tech companies in China.

The results show that integrative leadership has positive impact on employees’ innovation performance through its multilevel impacts on two mediation factors include psychological empowerment of employees and human resource flexibility.

This research used cross-sectional studies due to constraints of research conditions. The measurements of all variables are done simultaneously, whereas the effects of integrative leadership on the development of corporations should be presented in a dynamic process. Therefore, in the future research, vertical research design should be adopted to deeply explore the effectiveness mechanism of integrative leadership in the context of corporate internet-based transition.

In the internet era, leaders cannot blindly pursue organizational performance. They must establish a flexible organizational structure and institutions to provide a platform for employee development, and integrative leaders need to pay attention to inspire the potential of employees and stimulate the enthusiasm of employees.

This study investigates a new leadership-integrative leadership and the relationship between integrative leadership and innovation performance in the context of Internet-based transitional Chinese organizations, thereby making important theoretical contributions as well as offering practical suggestions for improving leadership efficiency and innovation performance.

This study aims to analyze the impact of the source of online word-of-mouth (WOM) on retail sales. Specifically, the authors focus on the relative impact of external and internal WOMs on book sales.

An empirical analysis is conducted with a panel data of sales and WOM for 87 books from Dangdang and Douban over a 14-day period based on two generalized least square regression models.

Results suggest that both internal WOM and external WOM have significant impact on product sales, and the impact of external WOM is relatively more significant.

WOM, especially the external WOM, plays an important role in consumers’ online purchase decisions.

This study is helpful for retailers to better understand the factors influencing the sales and thereby forecast the future sales more precisely. Besides, the research conclusion could also enlighten related decision makers to constantly improve technical platforms.

The purpose of this paper is to establish the horizontal displacement angle limit values under different performance level, use damage as the quantitative index of performance level and determine the design principle of the RACFST column for performance-based seismic fortification target based on the damage.

The paper is based on the seismic performance test of the RACFST column.

First, three-level seismic are introduced into the performance design foundation of the RACFST column. Second, the performance level of the RACFST column is divided into five grades: normal use, temporary use, use after repair, life safety and prevention of collapse. Third, the seismic performance targets of RACFST columns are divided into four categories: unacceptable situation, basic performance target, important performance target and special performance target.

The initial damage of the recycled aggregate occurs in the process of crushing and screening, and the damage evolution and development of the RACFST column occur under cyclic load. This is one of the problems that should not be avoided in the design of the seismic performance of the RACFST column. New levels are introduced in the performance design foundation of the RACFST column.