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The purpose of this paper is to investigate the tribological properties, antiwear mechanism and anticorrosion properties of two novel halogen-free borate ionic liquids (ILs) in 500 N base oil.

Different qualities of borate ILs were added to 500 N, and their tribological properties were tested on a four-ball machine. The tribological properties of the additives were evaluated by measuring the wear scar diameter (WSD) and average coefficient of friction. The antiwear and antifriction mechanism of ILs was analyzed by energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS).

The corrosion degrees of the two borate ILs 1-butyl-3-octyl-imidazole bis(mandelato)-borate ([OBIM][BMB]) and 1-butyl-3-(3-methoxypropyl)-imidazole bis(mandelato)-borate ([MPBIM][BMB]) are 1b and 1a, respectively, suggesting that they both possess significant corrosion resistance and can effectively protect the steel surface. When the concentration of [OBIM][BMB] and [MPBIM][BMB] is 2.5 Wt.%, the friction coefficient of 500 N is reduced by 37.3% and 26.2%, respectively. According to the analysis of the thermo gravimetric analyzer curves, [OBIM][BMB] and [MPBIM][BMB] decomposed at 369.7°C and 374.3°C, respectively, indicate that two additives both can be applied in higher temperature condition. The results of XPS and scanning electron microscope (SEM) reveal that [OBIM][BMB] and [MPBIM][BMB] both can react with the steel surface, thereby forming chemical films composed of iron oxide, B₂O₃ and organic N-containing compounds.

Two new environmentally friendly borate ILs were synthesized and their tribological properties in 500 N base oil were investigated for the first time.

The brake pipe system was an essential braking component of the railway freight trains, but the existing E-type sealing rings had problems such as insufficient low-temperature resistance, poor heat stability and short service life. To address these issues, low-phenyl silicone rubber was prepared and tested, and the finite element analysis and experimental studies on the sealing performance of its sealing rings were carried out.

The low-temperature resistance and thermal stability of the prepared low-phenyl silicone rubber were studied using low-temperature tensile testing, differential scanning calorimetry, dynamic thermomechanical analysis and thermogravimetric analysis. The sealing performance of the low-phenyl silicone rubber sealing ring was studied by using finite element analysis software abaqus and experiments.

The prepared low-phenyl silicone rubber sealing ring possessed excellent low-temperature resistance and thermal stability. According to the finite element analysis results, the finish of the flange sealing surface and groove outer edge should be ensured, and extrusion damage should be avoided. The sealing rings were more susceptible to damage in high compression ratio and/or low-temperature environments. When the sealing effect was ensured, a small compression ratio should be selected, and rubbers with hardness and elasticity less affected by temperature should be selected. The prepared low-phenyl silicone rubber sealing ring had zero leakage at both room temperature (RT) and −50 °C.

The innovation of this study is that it provides valuable data and experience for the future development of the sealing rings used in the brake pipe flange joints of the railway freight cars in China.

The paper aims to examine the consumption behavior of Chinese residents during economic transition. It explores whether Western theories of consumption are applicable to the Chinese situation, and then tests the hypothesis based on Chinese traditional culture and dynamic nature of system change.

The paper opted for an empirical‐based approach. A regression model was used to analyze annual consumption data from 1986 to 2008 in China.

The paper provides empirical insights and suggests that under the influence of Chinese traditional culture and dynamic change of the Chinese economic system, Chinese urban residents exhibit a special consumption pattern of an intermittent and cyclical nature.

The paper concludes that in order to make the consumption stimulation policy in China more effective, it is necessary to establish a series of measures such as establishing a sound social welfare system as well as narrowing the gap between the rich and the poor, which will substantially increase the buying power of the less‐privileged groups and thus will increase the overall spending in the society. Although the econometric model used in this paper is adequate, a different approach like time series econometrics may give us additional insights. Researchers are encouraged to test the hypothesis further by employing other methodologies. Second, due to the lack of its own theories in the emerging market, this study remains exploratory.

This paper fulfils an identified need to study the special consumption behavior of Chinese urban residents during the economic transition.