Epoxidation of cyclohexene to cyclohexene oxide was studied in a new type reactor—the ultrasound airlift loop reactor. The influences of ultrasound intensity, molar ratio of isobutyraldehyde to cyclohexene and oxy-ge...Epoxidation of cyclohexene to cyclohexene oxide was studied in a new type reactor—the ultrasound airlift loop reactor. The influences of ultrasound intensity, molar ratio of isobutyraldehyde to cyclohexene and oxy-gen gas flow rate on the conversion of cyclohexene and selectivity of cyclohexene oxide were investigated and dis-cussed, and the optimal operation condition was found, under which 95.2% conversion of cyclohexene and 90.7% selectivity of cyclohexene oxide were achieved. The ultrasonic airlift loop reactor utilizes the synergistic effect of sonochemsitry and higher oxygen transfer rate. Possible reaction mechanisms were outlined and the reason of ul-trasound promotion of epoxidation reactionwas analyzed.展开更多
Using the nonequilibrium Green's function technique,we investigate the current induced heat generationin Kondo regime.The Kondo effect influences the heat generation significantly.In the curve of heat generation v...Using the nonequilibrium Green's function technique,we investigate the current induced heat generationin Kondo regime.The Kondo effect influences the heat generation significantly.In the curve of heat generation versusthe bias,a negative differential of the heat generation is exhibited.The symmetry of the heat generation is destroyed bythe strong electron-electron interaction and the electron-phonon interaction.展开更多
The concept of using an externally applied magnetic field to add the drag force of a hypersonic reentry vehicle during the blackout was proposed by Bush in 1958.The increased drag force is caused by electromagnetic fo...The concept of using an externally applied magnetic field to add the drag force of a hypersonic reentry vehicle during the blackout was proposed by Bush in 1958.The increased drag force is caused by electromagnetic force that is introduced by interaction between the applied magnetic field and the weakly ionized airflow around the reentry vehicle.We investigated the influences of magnetic field intensities on the drag forces of a reentry vehicle by three dimensional(3-D)magnetohydrodynamics(MHD)simulation.The results showed that the drag fore exerted on the vehicle reached 25 kN when the magnetic field was 0.4 T.The drag force increased with the enhanced intial magnetic field.The bow shock was also pushed far away from the vehicle when the magnetic field was strengthened.展开更多
基金Supported by Qinglan Project Foundation of Jiangsu Province and Doctoral Dissertation Innovate Foundation of Nanjing Uni-versity of Technology (No.BSCS200508).
文摘Epoxidation of cyclohexene to cyclohexene oxide was studied in a new type reactor—the ultrasound airlift loop reactor. The influences of ultrasound intensity, molar ratio of isobutyraldehyde to cyclohexene and oxy-gen gas flow rate on the conversion of cyclohexene and selectivity of cyclohexene oxide were investigated and dis-cussed, and the optimal operation condition was found, under which 95.2% conversion of cyclohexene and 90.7% selectivity of cyclohexene oxide were achieved. The ultrasonic airlift loop reactor utilizes the synergistic effect of sonochemsitry and higher oxygen transfer rate. Possible reaction mechanisms were outlined and the reason of ul-trasound promotion of epoxidation reactionwas analyzed.
基金Supported by the Scientific Research Fund of Hunan Provincial Education Department,China under Grant Nos.08B016 and 09B021
文摘Using the nonequilibrium Green's function technique,we investigate the current induced heat generationin Kondo regime.The Kondo effect influences the heat generation significantly.In the curve of heat generation versusthe bias,a negative differential of the heat generation is exhibited.The symmetry of the heat generation is destroyed bythe strong electron-electron interaction and the electron-phonon interaction.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41204105,41104093,41174122)the Chinese Academy of Sciences (Grant No. KZZD-EW-01-3)
文摘The concept of using an externally applied magnetic field to add the drag force of a hypersonic reentry vehicle during the blackout was proposed by Bush in 1958.The increased drag force is caused by electromagnetic force that is introduced by interaction between the applied magnetic field and the weakly ionized airflow around the reentry vehicle.We investigated the influences of magnetic field intensities on the drag forces of a reentry vehicle by three dimensional(3-D)magnetohydrodynamics(MHD)simulation.The results showed that the drag fore exerted on the vehicle reached 25 kN when the magnetic field was 0.4 T.The drag force increased with the enhanced intial magnetic field.The bow shock was also pushed far away from the vehicle when the magnetic field was strengthened.