Microcellular polystyrene/LCP in situ composites with cell diameter less than 4 μm are prepared by using pressure quenching after supercritical CO 2 saturating at 25?MPa, 80℃ for 6 h. Characterization of the microce...Microcellular polystyrene/LCP in situ composites with cell diameter less than 4 μm are prepared by using pressure quenching after supercritical CO 2 saturating at 25?MPa, 80℃ for 6 h. Characterization of the microcellular structure of these blends is conducted to reveal the influence of LCP addition, LCP ratio and compatibilizer on the microcellular blends. The typical structure of these microcellular PS/LCP blends is that the microvoids only exist in the polystyrene phase. This structure results from the poor adsorption of supercritical CO 2 by LCP under the experimental conditions. The cell diameter of the microcellular blends is smaller than that of microcellular PS. An increase of cell size is also found from skin to core in microcellular blends. The microcellular blends with ZnSPS has larger cell size than those without ZnSPS, which is the consequence of the improvement of interfacial adhesion. It is because CO 2 could easily diffuse out through the gap between poor adhesion interface of blends without ZnSPS.展开更多
The process based on supercritical fluid extraction for reprocessing of the spent nuclear fuel has some remarkable advantages over the plutonium-uranium extraction(PUREX) process.Especially,it can minimize the generat...The process based on supercritical fluid extraction for reprocessing of the spent nuclear fuel has some remarkable advantages over the plutonium-uranium extraction(PUREX) process.Especially,it can minimize the generation of secondary waste.Dynamic reactive extraction of neodymium oxide(Nd2O3) in supercritical carbon dioxide(SC-CO2) containing tri-n-butyl phosphate-nitric acid(TBP-HNO3) complex was investigated.Temperature showed a positive effect on the extraction efficiency,while pressure showed a negative effect when the unsaturated TBP-HNO3 complex was employed for the dynamic reactive extraction of Nd2O3 in SC-CO2.Both temperature and pressure effects indicated that the kinetic process of the reactive extraction was controlled by the chemical reaction.A kinetic model was proposed to describe the extraction process.展开更多
Phase behavior of paclitaxel in solvent mixtures of dichloromethane and supercritical carbon dioxide was investigated using a supercritical phase monitor.Cloud point pressures were determined as a function of temperat...Phase behavior of paclitaxel in solvent mixtures of dichloromethane and supercritical carbon dioxide was investigated using a supercritical phase monitor.Cloud point pressures were determined as a function of temperature,pressure and paclitaxel content from 313.1 to 343.1K and pressures up to 33.52 MPa.The ternary mixtures exhibit a typical lower critical solution temperature behavior.When paclitaxel content increases,the single-phase region shrinks in size.Three cubic equations of state(Redlich-Kworng,Soave-Redlich-Kwong and Peng-Robinson equation of state) coupled with the van der Waals one-fluid mixing rules were selected to correlate the experimental data.The results indicate that SRK EOS coupled with two binary interaction parameters kij and lij can predict paclitaxel solubility for the best fit of experimental data.展开更多
文摘Microcellular polystyrene/LCP in situ composites with cell diameter less than 4 μm are prepared by using pressure quenching after supercritical CO 2 saturating at 25?MPa, 80℃ for 6 h. Characterization of the microcellular structure of these blends is conducted to reveal the influence of LCP addition, LCP ratio and compatibilizer on the microcellular blends. The typical structure of these microcellular PS/LCP blends is that the microvoids only exist in the polystyrene phase. This structure results from the poor adsorption of supercritical CO 2 by LCP under the experimental conditions. The cell diameter of the microcellular blends is smaller than that of microcellular PS. An increase of cell size is also found from skin to core in microcellular blends. The microcellular blends with ZnSPS has larger cell size than those without ZnSPS, which is the consequence of the improvement of interfacial adhesion. It is because CO 2 could easily diffuse out through the gap between poor adhesion interface of blends without ZnSPS.
基金Supported by the National Natural Science Foundation of China （20506014）.
文摘The process based on supercritical fluid extraction for reprocessing of the spent nuclear fuel has some remarkable advantages over the plutonium-uranium extraction(PUREX) process.Especially,it can minimize the generation of secondary waste.Dynamic reactive extraction of neodymium oxide(Nd2O3) in supercritical carbon dioxide(SC-CO2) containing tri-n-butyl phosphate-nitric acid(TBP-HNO3) complex was investigated.Temperature showed a positive effect on the extraction efficiency,while pressure showed a negative effect when the unsaturated TBP-HNO3 complex was employed for the dynamic reactive extraction of Nd2O3 in SC-CO2.Both temperature and pressure effects indicated that the kinetic process of the reactive extraction was controlled by the chemical reaction.A kinetic model was proposed to describe the extraction process.
基金Supported by the National Natural Science Foundation of China （21076084 20676046） the Fundamental Research Funds for the Central Universities （2011ZZ0006）
文摘Phase behavior of paclitaxel in solvent mixtures of dichloromethane and supercritical carbon dioxide was investigated using a supercritical phase monitor.Cloud point pressures were determined as a function of temperature,pressure and paclitaxel content from 313.1 to 343.1K and pressures up to 33.52 MPa.The ternary mixtures exhibit a typical lower critical solution temperature behavior.When paclitaxel content increases,the single-phase region shrinks in size.Three cubic equations of state(Redlich-Kworng,Soave-Redlich-Kwong and Peng-Robinson equation of state) coupled with the van der Waals one-fluid mixing rules were selected to correlate the experimental data.The results indicate that SRK EOS coupled with two binary interaction parameters kij and lij can predict paclitaxel solubility for the best fit of experimental data.
