Surface tension of sodium aluminate solution and the contact angle between Al(OH)3 particles and aluminate solution were measured, then the dependence of Al(OH)3 solubility on its particle size was calculated and ...Surface tension of sodium aluminate solution and the contact angle between Al(OH)3 particles and aluminate solution were measured, then the dependence of Al(OH)3 solubility on its particle size was calculated and thus the variation of the critical nucleus sizes was determined based on the Ostwald ripening formula. The results show that the Al(OH)3 solubility in sodium aluminate solution decreases with the increment of particle size, and the critical nucleus sizes increase with the rise of alkali concentration, caustic ratio and precipitation temperature. The results also imply that the presence of small particles in seeded precipitation system is an important factor to limit the depth of precipitation.展开更多
The interplay between chemistry and interfacial-tension-driven hydrodynamic instabilities has been studied experimentally. The system on hand consists of two immiscible liquids separated along an initially plane inter...The interplay between chemistry and interfacial-tension-driven hydrodynamic instabilities has been studied experimentally. The system on hand consists of two immiscible liquids separated along an initially plane interface at which an interfacial reaction takes place to produce in situ a surfactant. It is identified that the dynamics of the system depends on the orientation of the Hele-Shaw cell with respect to the vector of gravity. If the nele-Shaw cell is placed vertically, Marangoni cells with vigorous convection develop in both phases along a nearly planar interface. However, if the Hele-Shaw cell is tilted off the gravity, the instabilities in the system are characterized by the large scale interracial deformation with a spatio-temporal periodicity together with the chemo-Marangoni convection. The focus is on the exploration of the transition from the cellular mode to the large scale interfacial deformation.展开更多
基金Project(51274242)supported by the National Natural Science Foundation of China
文摘Surface tension of sodium aluminate solution and the contact angle between Al(OH)3 particles and aluminate solution were measured, then the dependence of Al(OH)3 solubility on its particle size was calculated and thus the variation of the critical nucleus sizes was determined based on the Ostwald ripening formula. The results show that the Al(OH)3 solubility in sodium aluminate solution decreases with the increment of particle size, and the critical nucleus sizes increase with the rise of alkali concentration, caustic ratio and precipitation temperature. The results also imply that the presence of small particles in seeded precipitation system is an important factor to limit the depth of precipitation.
基金Deutsche Forschung Gemainschaft(Ec/201/1-5)Deutsches Zentrum fuer Luft und Raumfahrt(50WM0058).
文摘The interplay between chemistry and interfacial-tension-driven hydrodynamic instabilities has been studied experimentally. The system on hand consists of two immiscible liquids separated along an initially plane interface at which an interfacial reaction takes place to produce in situ a surfactant. It is identified that the dynamics of the system depends on the orientation of the Hele-Shaw cell with respect to the vector of gravity. If the nele-Shaw cell is placed vertically, Marangoni cells with vigorous convection develop in both phases along a nearly planar interface. However, if the Hele-Shaw cell is tilted off the gravity, the instabilities in the system are characterized by the large scale interracial deformation with a spatio-temporal periodicity together with the chemo-Marangoni convection. The focus is on the exploration of the transition from the cellular mode to the large scale interfacial deformation.