The lubricating characteristics of CVTF(continuously variable transmission fluid) mixed with a multi-functional complex additive were studied. The said complex additive contained an organic borate ester and a new type...The lubricating characteristics of CVTF(continuously variable transmission fluid) mixed with a multi-functional complex additive were studied. The said complex additive contained an organic borate ester and a new type of friction improver comprising phosphorus element and poly-methylmethacrylate(PMMA), and a viscosity index improver. The viscosity-pressure characteristics were evaluated by a high-pressure quartz viscometer, and the anti-wear property was investigated by a four-ball friction tester. The mechanism of lubrication by the CVTF was studied using X-ray photoelectron spectroscopy(XPS). The results showed that CVTF T10, which contained a multi-functional complex additive, exhibited excellent properties, featuring greater solidification pressure and pressure-viscosity coefficient, improved oil film strength, and low wear value. These attributes meet the special CVTF requirements for "high friction and low wear" that make it possible to provide both traction and lubrication. The lubricating mechanism was varied using different functional elements, such as inert and active elements. Sulfur and phosphorus are active extreme pressure elements that can react on the metal friction surface and produce an extreme pressure lubrication film. Boron is an inert functional element and does not react upon the metal surface; boron is only adsorbed onto the metal surface to act as a lubricant for adsorption film and fillers.展开更多
The primary objective of this study was to evaluate the existing conditions and the stability of a mining site in which the unique features of seismicity, mining activity, hydrological conditions, geological condition...The primary objective of this study was to evaluate the existing conditions and the stability of a mining site in which the unique features of seismicity, mining activity, hydrological conditions, geological conditions, environmental conditions, and future development plans were considered. In particular, the potential subsidence locations near the proposed construction site, the effects of mining boundary profile,and the influence scope of the mining activity on the neighboring areas were investigated using the finite element method. The study results indicate:(1) the overlying sandstone layer to the coal layer is the key to the stability of the mining roof;(2) the broken boundary has the most effect, followed by the arc boundary and linear boundary;(3) the safe distance from the mining boundary should be at least400 m if the proposed structure is to be built near an active mining site. Other relevant engineering recommendations are also proposed. The concluded results from this study may serve as a guide to other similar sites in the world.展开更多
基金financially supported by the China National Machinery Industry Corporation Science & Technology Development Fund (SINOMACH12 No.180)
文摘The lubricating characteristics of CVTF(continuously variable transmission fluid) mixed with a multi-functional complex additive were studied. The said complex additive contained an organic borate ester and a new type of friction improver comprising phosphorus element and poly-methylmethacrylate(PMMA), and a viscosity index improver. The viscosity-pressure characteristics were evaluated by a high-pressure quartz viscometer, and the anti-wear property was investigated by a four-ball friction tester. The mechanism of lubrication by the CVTF was studied using X-ray photoelectron spectroscopy(XPS). The results showed that CVTF T10, which contained a multi-functional complex additive, exhibited excellent properties, featuring greater solidification pressure and pressure-viscosity coefficient, improved oil film strength, and low wear value. These attributes meet the special CVTF requirements for "high friction and low wear" that make it possible to provide both traction and lubrication. The lubricating mechanism was varied using different functional elements, such as inert and active elements. Sulfur and phosphorus are active extreme pressure elements that can react on the metal friction surface and produce an extreme pressure lubrication film. Boron is an inert functional element and does not react upon the metal surface; boron is only adsorbed onto the metal surface to act as a lubricant for adsorption film and fillers.
基金Shaanxi Research Institute of Seismic Engineering, China for providing the necessary financial support for this study
文摘The primary objective of this study was to evaluate the existing conditions and the stability of a mining site in which the unique features of seismicity, mining activity, hydrological conditions, geological conditions, environmental conditions, and future development plans were considered. In particular, the potential subsidence locations near the proposed construction site, the effects of mining boundary profile,and the influence scope of the mining activity on the neighboring areas were investigated using the finite element method. The study results indicate:(1) the overlying sandstone layer to the coal layer is the key to the stability of the mining roof;(2) the broken boundary has the most effect, followed by the arc boundary and linear boundary;(3) the safe distance from the mining boundary should be at least400 m if the proposed structure is to be built near an active mining site. Other relevant engineering recommendations are also proposed. The concluded results from this study may serve as a guide to other similar sites in the world.
