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The purpose of this paper is to investigate the mechanical and wear properties of Y-TZP/Al₂O₃ nanocomposites.

In this paper, the Y-TZP/Al₂O₃ nanocomposites with different crystal-sizes are designed and fabricated by hot pressing. Their mechanical and anti-wear properties are investigated, and the wear mechanism is studied by scanning electron microscopy, X-ray diffraction, and transmission electron microscope and so on.

The experimental results indicate that the wear of Y-TZP/Al₂O₃ nanocomposites can be divided into two regimes: mild wear regime and normal wear regime. In mild wear regimes, the relationship between wear resistance (ɛ) and hardness (H) of the material can be described as: ɛ−1∝H−1. The corresponding relationship among wear resistance, hardness and toughness (K_IC) of the material in normal wear regime can be described as: ɛ−1∝H−1K _IC −4.

In this paper, the mechanical and anti-wear properties of Y-TZP/Al₂O₃ nanocomposites are systematically investigated. The relation between mechanical properties and wear resistance is revealed.

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 investigate the hydrolytic stability of several S‐hydroxyethyl N,N‐dialkyl dithiocarbamate‐derived borates SNB1, SNB2, and SNB3, to evaluate their tribological performances used as additives in polyalpha olefins (PAO), and to explore the tribochemical action mechanism.

First, the three additives are synthesized and characterized. Second, the hydrolytic stabilities of the three compounds are investigated. As the third step, they are, respectively, added to PAO and a series of samples with different concentrations of the additives in PAO are prepared, respectively. Their tribological properties are evaluated with two types of four‐ball machines, and then the wear scars were observed using a JSM‐5600LV scanning electron microscope. Finally, the elements on the worn surface are analyzed with a X‐ray photoelectron spectroscope (XPS).

The three novel compounds possess relatively good hydrolytic stabilities, excellent anti‐wear (AW) performances, friction reduction properties, and load‐carrying capacity. There is an optimum concentration of each of the three additives for their AW properties. According to the XPS analytical results, a boundary lubrication protective film has formed during friction consisting of FeSO₄ film, Fe₂O₃ film, and the complicated adsorption film composed of N‐containing organic compounds. In the protective films, a large quantity of compounds containing element B is not found.

The antioxidation performances and the anticorrosion properties are not estimated.

Three novel AW/extreme pressure (EP) additives are synthesized, and may be they have the potential industrial application as AW/EP additives in lubricating oil.

The present work provides a research method of N,S‐containing organic borates as lubricating oil additives.

Despite the importance of tourism ethnocentrism in emerging tourism destinations, there is limited, but growing, research interest in this area. This study aims to respond to current calls for investigating mechanisms that can promote tourism ethnocentrism in both emerging and developed tourism destinations.

There is an increasing focus on the significance of tourism ethnocentrism in determining the success of tourism development and marketing. However, the relationship between tourism ethnocentrism and various tourism-related concepts remains inadequately explored. Hence, this study aims to address the growing need to examine the factors that bolster tourism ethnocentrism in emerging tourism destinations using stimulus-organism-response (S-O-R) paradigm.

Using a quantitative cross-sectional survey design, the study gathered data from 434 respondents, which were subsequently analyzed using structural equation modeling.

The results highlight crucial findings: destination promotional videos contribute to the accumulation of tourism knowledge, which, in turn, fosters tourism ethnocentrism. These findings imply that tourism knowledge mediates the relationship between destination promotional videos and tourism ethnocentrism.

The study strongly advocates for using destination promotional videos to enhance resident support for tourism by augmenting perceived tourism knowledge. Managers in destination marketing organizations (DMOs) are encouraged to adopt destination promotional videos as a novel approach for promoting inclusive tourism development by enhancing tourism knowledge as mechanisms for promoting tourism ethnocentrism.

By considering and proposing destination promotional videos as an ambivalent mechanism of tourism ethnocentrism, this study is an academic endeavor that advances insights into the occurrence of tourism ethnocentrism as an important component of inclusive tourism development.