The influence of nano-particles on CO2absorption was studied experimentally in a stirred thermostatic reactor.Nano-Al2O3and carbon nanotube(CNT) particles which showed different hydrophobic properties were chosen for ...The influence of nano-particles on CO2absorption was studied experimentally in a stirred thermostatic reactor.Nano-Al2O3and carbon nanotube(CNT) particles which showed different hydrophobic properties were chosen for the investigation.The experimental results were compared with that of micron-size activated carbon(AC)and Al2O3particles.From the results,no enhancement by micron-size Al2O3was found,and with the increase of Al2O3concentration,the enhancement factor decreased.However,nano-Al2O3showed a weak enhancement for the CO2absorption.AC and CNT particles all intensified the gas-liquid mass transfer effectively,yet the trend of the enhancement factor with stirring speed for the two particles was different.With increasing stirring speed,the enhancement factor of AC particles was decreased,whereas in CNT suspensions it was increased.The experimental phenomena demonstrated a difference in enhancement mechanism for different size particles.For nano-particles,besides the influence of adsorbability and hydrophobicity,the micro-convection caused by Brownian motion should be also taken into account.Considering the micro-convection effect,a theoretical model was developed to shed light on the absorption enhancement by nano-particles.展开更多
采用磁控溅射工艺在PET衬底上依次沉积了Al_2O_3和SiO_2薄膜,制备出SiO_2/Al_2O_3/PET复合膜。利用扫描电镜和透湿仪对复合膜的表面形貌和透湿性能进行表征。研究了制备Al_2O_3膜层的射频功率、氩气流量、本底真空度和溅射时间4个参数...采用磁控溅射工艺在PET衬底上依次沉积了Al_2O_3和SiO_2薄膜,制备出SiO_2/Al_2O_3/PET复合膜。利用扫描电镜和透湿仪对复合膜的表面形貌和透湿性能进行表征。研究了制备Al_2O_3膜层的射频功率、氩气流量、本底真空度和溅射时间4个参数对复合膜透湿率的影响。结果表明:复合膜的透湿率随着本底真空度的升高而减小,随着射频功率、氩气流量和溅射时间的增加均呈现先减小后增大的变化趋势;4个制备参数对复合膜透湿率的影响程度由大到小依次是本底真空度、氩气流量、射频功率、溅射时间;4个制备参数的较优组合为本地真空度0.5×10^(-3)Pa,射频功率300 W,溅射时间6 min,氩气流量70 m L·min^(-1)。展开更多
文摘The influence of nano-particles on CO2absorption was studied experimentally in a stirred thermostatic reactor.Nano-Al2O3and carbon nanotube(CNT) particles which showed different hydrophobic properties were chosen for the investigation.The experimental results were compared with that of micron-size activated carbon(AC)and Al2O3particles.From the results,no enhancement by micron-size Al2O3was found,and with the increase of Al2O3concentration,the enhancement factor decreased.However,nano-Al2O3showed a weak enhancement for the CO2absorption.AC and CNT particles all intensified the gas-liquid mass transfer effectively,yet the trend of the enhancement factor with stirring speed for the two particles was different.With increasing stirring speed,the enhancement factor of AC particles was decreased,whereas in CNT suspensions it was increased.The experimental phenomena demonstrated a difference in enhancement mechanism for different size particles.For nano-particles,besides the influence of adsorbability and hydrophobicity,the micro-convection caused by Brownian motion should be also taken into account.Considering the micro-convection effect,a theoretical model was developed to shed light on the absorption enhancement by nano-particles.
文摘采用磁控溅射工艺在PET衬底上依次沉积了Al_2O_3和SiO_2薄膜,制备出SiO_2/Al_2O_3/PET复合膜。利用扫描电镜和透湿仪对复合膜的表面形貌和透湿性能进行表征。研究了制备Al_2O_3膜层的射频功率、氩气流量、本底真空度和溅射时间4个参数对复合膜透湿率的影响。结果表明:复合膜的透湿率随着本底真空度的升高而减小,随着射频功率、氩气流量和溅射时间的增加均呈现先减小后增大的变化趋势;4个制备参数对复合膜透湿率的影响程度由大到小依次是本底真空度、氩气流量、射频功率、溅射时间;4个制备参数的较优组合为本地真空度0.5×10^(-3)Pa,射频功率300 W,溅射时间6 min,氩气流量70 m L·min^(-1)。