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This study aims to analyze the wettability of the self-developed Sn–Bi–Zn solder and to conduct a series of analysis on the wetting kinetics, diffusion phenomenon and interfacial reaction of Sn–Bi–Zn solder on Cu substrate.

The wetting kinetics, diffusion phenomenon and interfacial reaction of Sn–Bi–Zn solder on Cu substrate were analyzed by experiments. The interface was observed by scanning electron microscope to study the effect of Zn content on its interface.

With the increase in brazing temperature, the final spreading equivalent radius of the solder increases significantly, and the final contact angle of the solder decreases significantly. In addition, when the Zn content is 1%, the spreading effect of solder is the best, the equivalent radius is the largest and the contact angle is the smallest. According to the microstructural analysis, the thick intermetallic compounds layer of the Sn–15Bi–xZn solders on the Cu substrate can be effectively decreased by adding appropriate Zn content.

The wetting kinetics, diffusion phenomenon and interfacial reaction of Sn–15Bi–xZn solder on Cu substrate at different temperatures have not been studied yet.

For moderate pressure and high pressure gear pumps, the temperature failure problem of bearings is now of considerable concern because of their heavy loads. However, the compact structure and the efficiency consideration make it extremely difficult to improve the bearing cooling. A self-circulating oil bearing system is developed for gear pumps with self-lubricating bearings to solve this problem. The oil is aspirated in from the low pressure chamber of the gear pump and discharged to the same chamber by using the pressure difference in the journal bearing, thus achieving the self-circulation.

An experiment test rig has been built for the feasibility study. The oil flow rate under different speeds has been recorded. Furthermore, the temperatures of the bearings with or without the oil circulation have been compared. Additionally, the oil flow in the test rig has been simulated using computational fluid dynamics codes.

The experimental and numerical results agree well. The experimental results indicate that the oil flow rate increases approximately linearly with the speed and the bearing temperature can be lowered successfully. The calculation results indicate that the bearing load capacity is nearly the same. Both the experimental and numerical studies establish that the self-circulating oil bearing system works successfully.

As far as the authors know, it is the first time to find that the self-circulation can be built using the pressure difference in the bearing oil film, and this principle can be applied in the cooling and lubrication of the gear pumps to solve the temperature failure problem.

The booming social media attracts construction professionals (CPs) to express emotions caused by work pressure (WP) through online behaviors. Previous works focus on the analysis of WP and emotions but do not adequately consider how WP can be reflected through online emotions. Thus, this study aims to attempt to explore the quantitative relationship between online emotional intensity and WP.

This study developed a linguistic-sticker (LS) model to quantitatively evaluate the sentiment intensity of posts published on social media. Moreover, the authors designed two econometric models of ordinary least squares regression and negative binomial regression to test the hypothesis.

The research found that posts with stronger negative sentiment (or positive sentiment) indicate that CPs face higher (or lower) WP. Besides, there is a negative bias between the sentiment intensity of posts and the comment quantity.

The positive correlation between sentiment intensity of posts and WP has been confirmed, which indicates that construction managers should pay more attention to CPs' behavior on social media, and take a more direct way to analyze work-related online behavior (e.g. posting, commenting). The dynamic monitoring of emotion-related posts also provides a direct basis for the management team to learn about CP's pressure status and propose measures to reduce their negative emotions. Furthermore, the emotional posts published by CPs on social media provide a direct basis for team managers to obtain their psychological state.

The research contributes to incorporating CPs' emotions into the LS model and to providing information systems artifacts and new findings on the analysis of WP and online emotions.

This study aims to understand the normative expectations of travelers on the services and experiences provided by Buddhism-themed hotels as well as how service providers perceive such expectations. The growth of religion-themed hotels in China follows a larger and more generalized global marketing trend in terms of providing tourists and consumers with “themed” experiences.

Using the service quality model, this study investigates these expectations of Buddhism-themed hotels in China. The Delphi method was used with two expert panels, namely, travelers and tourism/hotel practitioners. Preliminary interviews revealed 98 normative expectations from Buddhism-themed hotels. Two sets of Delphi questionnaires were used to compare tourist expectations with practitioner perceptions.

Results show a wide range of expectations of travelers staying in Buddhism-themed hotels. They also reveal how the expectations of the two groups aligned as well as differed.

This study extends the application of the service quality model to the context of religion-themed hotels. As this study adopted the Delphi technique through criterion sampling, future studies should use a larger random sample to verify the results of this study.

The results help religion-themed hoteliers to understand their customer expectations better.

Given the lack of studies on religion-themed hotels, especially on the gap between tourist expectations and service providers’ perceptions, this study is a timely contribution to improve the understanding on the needs and expectations of customers when visiting religion-themed hotels.

This paper is written as an attempt to employ the Chinese Social Science Citation Index (CSSCI) in the evaluation of Chinese humanities and social science research.

This paper uses statistics in the CSSCI (2000‐2004) to analyze the academic impact of researchers, papers and works, institutions and regions on Chinese humanities and social science research.

The authors identify 100 highly cited people, 50 highly cited papers, 50 highly cited works, 20 highly productive institutions and 20 highly cited institutions. Also provided is some regional information about Chinese humanities and social science research.

It is hoped that the CSSCI, as well as the analysis and evaluation based on it, will give researchers a better understanding of Chinese humanities and social science research.

The lubrication of the high-speed reducer of an electric vehicle is investigated. The specific contents include visualization of the flow field inside reducer, lubrication evaluation of bearings and efficiency experiment.

The flow field inside reducer at five working conditions: straight, uphill, downhill, left lean and right lean is simulated by smoothed particle hydrodynamics (SPH). According to the instantaneous number of particles through bearings, the lubrication states of bearings are evaluated. The test platform is set up to measure the efficiency of the reducer.

The flow field inside the reducer is obtained, the lubrication of bearings needs to be improved, the efficiency of the electric vehicle reducer meets the requirement.

The SPH method is used to simulate lubrication instead of using the traditional grid-based finite volume method. A novel method to evaluate the lubrication of bearings is proposed. The method and conclusions can guide electric vehicle reducer design.