Membrane fouling seriously restricts applications of membrane technology. A novel strategy was applied in this study to retard membrane fouling by changing operating pressure with the pressure responsibility membrane....Membrane fouling seriously restricts applications of membrane technology. A novel strategy was applied in this study to retard membrane fouling by changing operating pressure with the pressure responsibility membrane. A polyurethane-based hollow fiber membrane was used to treat surface water for evaluating the effect of operating pressure on membrane fouling. Some bench-scale tests in dead-end mode were carried out. In the experiments without backwashing, as operating pressure increased, severe membrane fouling occurred on membrane surface, while the permeate quality was improved obviously, which is considered to be due to shrinkage deformation. The total resistance, irreversible resistance and reversible resistance under different backwash pressures were determined in filtration/backwashing test. With the increase of backwash pressure, the total resistance decreased, and more importantly, the irreversible resistance also decreased, which implies that small particles deposited inside membrane pores and cake layers on membrane surface are effectively removed. Similar results could be obtained in mass balance tests. The results of the present study indicate that the application of pressure responsibility membrane in surface water treatment may be an effective strategy for reducing membrane fouling.展开更多
Amorphous indium-gallium-zinc oxide （IGZO） transparent conductive thin films are prepared on glass substrates by radio frequency （RF） magnetron sputtering. The effects of seven factors, which are substrate tempera...Amorphous indium-gallium-zinc oxide （IGZO） transparent conductive thin films are prepared on glass substrates by radio frequency （RF） magnetron sputtering. The effects of seven factors, which are substrate temperature, sputtering atmosphere, working pressure, sputtering power, annealing temperature, negative bias voltage and sputtering time, on Hall mobility, transmittance and surface roughness are studied through orthogonal experiments. The results show that the effects of working pressure, substrate temperature and sputtering atmosphere on performance of films are the most prominent. According to the experimental results and discussion, relatively reasonable process parameters are obtained, which are working pressure of 0.35 Pa, substrate temperature of 200 ℃, sputtering atmosphere of Ar, sputtering power of 125 W, sputtering time of 30 min, negative bias voltage of 0 V and annealing temperature of 300 ℃.展开更多
基金Supported by the National Natural Science Foundation of China(51078264,51108314,51108315,51138008)
文摘Membrane fouling seriously restricts applications of membrane technology. A novel strategy was applied in this study to retard membrane fouling by changing operating pressure with the pressure responsibility membrane. A polyurethane-based hollow fiber membrane was used to treat surface water for evaluating the effect of operating pressure on membrane fouling. Some bench-scale tests in dead-end mode were carried out. In the experiments without backwashing, as operating pressure increased, severe membrane fouling occurred on membrane surface, while the permeate quality was improved obviously, which is considered to be due to shrinkage deformation. The total resistance, irreversible resistance and reversible resistance under different backwash pressures were determined in filtration/backwashing test. With the increase of backwash pressure, the total resistance decreased, and more importantly, the irreversible resistance also decreased, which implies that small particles deposited inside membrane pores and cake layers on membrane surface are effectively removed. Similar results could be obtained in mass balance tests. The results of the present study indicate that the application of pressure responsibility membrane in surface water treatment may be an effective strategy for reducing membrane fouling.
文摘Amorphous indium-gallium-zinc oxide （IGZO） transparent conductive thin films are prepared on glass substrates by radio frequency （RF） magnetron sputtering. The effects of seven factors, which are substrate temperature, sputtering atmosphere, working pressure, sputtering power, annealing temperature, negative bias voltage and sputtering time, on Hall mobility, transmittance and surface roughness are studied through orthogonal experiments. The results show that the effects of working pressure, substrate temperature and sputtering atmosphere on performance of films are the most prominent. According to the experimental results and discussion, relatively reasonable process parameters are obtained, which are working pressure of 0.35 Pa, substrate temperature of 200 ℃, sputtering atmosphere of Ar, sputtering power of 125 W, sputtering time of 30 min, negative bias voltage of 0 V and annealing temperature of 300 ℃.
