Fume suppression mechanisms and the effect of expanded graphite on the performance of asphalt were studied by applying infrared spectroscopy(FT-IR), X-ray diffraction(XRD), scanning electron microscopy(SEM) and ...Fume suppression mechanisms and the effect of expanded graphite on the performance of asphalt were studied by applying infrared spectroscopy(FT-IR), X-ray diffraction(XRD), scanning electron microscopy(SEM) and comprehensive thermal analysis(TG, DSC). The experimental results confirm that asphalt which is mixed with expandable graphite will expand in the process of hot mix, and the expanded graphite layer will swell by the light component in the asphalt. The light component in the asphalt and PAHs adsorption on expanded graphite surface or part of the plug in the expanded graphite layer between plates made nucleation crystallization growth. And the Van der Waals force and the bonding of the lattice can effectively restrain the asphalt fume release. Meanwhile, the expanding agent with oxidative can spread into the asphalt, leading to asphalt oxygenated and plastic abate, while the ductility decreases. Expanded graphite, SBS modifier and environment- friendly plasticizers are used to composite modified asphalt. According to asphalt fume release experiment, normal test of asphalt performance, Brookfield viscosity test, RTFOT test and asphalt mixture tests(high temperature stability, low temperature stability, water stability), it has been proven that the modified asphalt’s performance is better than that of matrix asphalt and equivalent to that of SBS modified asphalt. Furthermore, it has good fume suppression effect.展开更多
This study presents two kinds of rolling robots that are able to roll by deforming their outer shapes with a single degree of freedom.Each robot is an essential multi-loop planar expandable linkage constructed by a co...This study presents two kinds of rolling robots that are able to roll by deforming their outer shapes with a single degree of freedom.Each robot is an essential multi-loop planar expandable linkage constructed by a concave outer loop and several inner parallelogram loops.In this study,the mechanical design of the robots is introduced.Dynamic rolling process is further analyzed on the basis of zero moment point method,and a morphing strategy is proposed to guarantee a stable dynamic rolling process.A novel passive rolling locomotion is also developed,which enables the robots to roll and stand on a slope.To verify the design,two prototypes are manufactured,wherein the dynamic and passive rolling locomotion are carried out.展开更多
基金Funded by the National Natural Science Foundation of China(No.51078372)the Doctoral Program of Higher Specialized Research Foundation(No.20105522110002)
文摘Fume suppression mechanisms and the effect of expanded graphite on the performance of asphalt were studied by applying infrared spectroscopy(FT-IR), X-ray diffraction(XRD), scanning electron microscopy(SEM) and comprehensive thermal analysis(TG, DSC). The experimental results confirm that asphalt which is mixed with expandable graphite will expand in the process of hot mix, and the expanded graphite layer will swell by the light component in the asphalt. The light component in the asphalt and PAHs adsorption on expanded graphite surface or part of the plug in the expanded graphite layer between plates made nucleation crystallization growth. And the Van der Waals force and the bonding of the lattice can effectively restrain the asphalt fume release. Meanwhile, the expanding agent with oxidative can spread into the asphalt, leading to asphalt oxygenated and plastic abate, while the ductility decreases. Expanded graphite, SBS modifier and environment- friendly plasticizers are used to composite modified asphalt. According to asphalt fume release experiment, normal test of asphalt performance, Brookfield viscosity test, RTFOT test and asphalt mixture tests(high temperature stability, low temperature stability, water stability), it has been proven that the modified asphalt’s performance is better than that of matrix asphalt and equivalent to that of SBS modified asphalt. Furthermore, it has good fume suppression effect.
基金Supported by the Fundamental Research Funds for the Central Universities(Grant No.2019JBZ109).
文摘This study presents two kinds of rolling robots that are able to roll by deforming their outer shapes with a single degree of freedom.Each robot is an essential multi-loop planar expandable linkage constructed by a concave outer loop and several inner parallelogram loops.In this study,the mechanical design of the robots is introduced.Dynamic rolling process is further analyzed on the basis of zero moment point method,and a morphing strategy is proposed to guarantee a stable dynamic rolling process.A novel passive rolling locomotion is also developed,which enables the robots to roll and stand on a slope.To verify the design,two prototypes are manufactured,wherein the dynamic and passive rolling locomotion are carried out.