Hierarchically porous ZSM‐5 (SiO2/Al2O3 ≈ 120) containing phosphorus was prepared by a one‐step post‐synthesis treatment involving controlled desilication and phosphorous modification. The hierarchically porous ZS...Hierarchically porous ZSM‐5 (SiO2/Al2O3 ≈ 120) containing phosphorus was prepared by a one‐step post‐synthesis treatment involving controlled desilication and phosphorous modification. The hierarchically porous ZSM‐5 featured high thermal and hydrothermal stability. The obtained ZSM‐5zeolites were systematically characterized by X‐ray diffraction, scanning electron microscopy,transmission electron microscopy, N2 adsorption‐desorption, NH3 temperature‐programmed desorption,and 27Al and 31P magic‐angle spinning nuclear magnetic resonance spectroscopy. Theprepared ZSM‐5 displayed enhanced activity and prolonged lifetime toward hydrocarbon cracking.The high activity was attributed to improved coke tolerance owing to the presence of the highlystable mesoporous network of ZSM‐5 and acid sites introduced upon phosphorus modification.Additionally a mechanism of the stabilization of the zeolites by phosphorus was proposed and discussed.展开更多
Thailand rice husk ash was used to synthesize zeolite by hydrothermal treatment. Raw rice husk ash material and zeolitic products were characterized in terms of specific surface area (BET method), morphological anal...Thailand rice husk ash was used to synthesize zeolite by hydrothermal treatment. Raw rice husk ash material and zeolitic products were characterized in terms of specific surface area (BET method), morphological analysis (SEM), mineralogical composition (XRD) and CEC (cation exchange capacity). LOI (Loss of ignition) of rice husk ash was also evaluated. Result indicated that the rice husk ash sample from Roi-Et Green power plant in the Northeastern of Thailand with combustion temperature of 650 ℃ has a high content of SiO2 (above 90 wt.%). Zeolite-X from rice husk ash with high content of Si was successfully synthesized using hydrothermal treatment. The zeolitic material synthesized with the optimal condition possessed a maximum value of CEC of 503 meq/100g, and it has potentiality to be used as ion exchangers.展开更多
Novel nitrogen doped carbon quantum dots were successfully fabricated by a hydrothermal method wxth eggplam sepals as carbon source. The carbon materials were characterized by transmission electron microscopy (TEM),...Novel nitrogen doped carbon quantum dots were successfully fabricated by a hydrothermal method wxth eggplam sepals as carbon source. The carbon materials were characterized by transmission electron microscopy (TEM), UV-Vis adsorption, Fourier-transformed infrared spectroscopy (FTIR), fluorescence and the X-ray photoelectron spectroscopy (XPS) measurements, respectively. The carbon quantum dots showed excellent photoluminescence property with high stability in phosphate buffer solution with different pH values from 5 to 9, even in the cell culture medium supplied with the fetal bovine serum. Meanwhile, we also studied the interaction of carbon quantum dots with living HeLa cells with confocal microscopy. Our results indicated that the carbon quantum dots can enter the living HeLa cells by cellular penetration.展开更多
基金supported by the National Natural Science Foundation of China (21403070, 21573073)National Key Technology Research and De-velopment Program (2012BAE05B02)Shanghai Leading Academic Discipline Project (B409)~~
文摘Hierarchically porous ZSM‐5 (SiO2/Al2O3 ≈ 120) containing phosphorus was prepared by a one‐step post‐synthesis treatment involving controlled desilication and phosphorous modification. The hierarchically porous ZSM‐5 featured high thermal and hydrothermal stability. The obtained ZSM‐5zeolites were systematically characterized by X‐ray diffraction, scanning electron microscopy,transmission electron microscopy, N2 adsorption‐desorption, NH3 temperature‐programmed desorption,and 27Al and 31P magic‐angle spinning nuclear magnetic resonance spectroscopy. Theprepared ZSM‐5 displayed enhanced activity and prolonged lifetime toward hydrocarbon cracking.The high activity was attributed to improved coke tolerance owing to the presence of the highlystable mesoporous network of ZSM‐5 and acid sites introduced upon phosphorus modification.Additionally a mechanism of the stabilization of the zeolites by phosphorus was proposed and discussed.
文摘Thailand rice husk ash was used to synthesize zeolite by hydrothermal treatment. Raw rice husk ash material and zeolitic products were characterized in terms of specific surface area (BET method), morphological analysis (SEM), mineralogical composition (XRD) and CEC (cation exchange capacity). LOI (Loss of ignition) of rice husk ash was also evaluated. Result indicated that the rice husk ash sample from Roi-Et Green power plant in the Northeastern of Thailand with combustion temperature of 650 ℃ has a high content of SiO2 (above 90 wt.%). Zeolite-X from rice husk ash with high content of Si was successfully synthesized using hydrothermal treatment. The zeolitic material synthesized with the optimal condition possessed a maximum value of CEC of 503 meq/100g, and it has potentiality to be used as ion exchangers.
基金supported by the National Science Foundation for Excellent Young Scholar of China(21322510)the Natural Science Foundation of Jilin Province(201215092)the President Funds of the Chinese Academy of Sciences
文摘Novel nitrogen doped carbon quantum dots were successfully fabricated by a hydrothermal method wxth eggplam sepals as carbon source. The carbon materials were characterized by transmission electron microscopy (TEM), UV-Vis adsorption, Fourier-transformed infrared spectroscopy (FTIR), fluorescence and the X-ray photoelectron spectroscopy (XPS) measurements, respectively. The carbon quantum dots showed excellent photoluminescence property with high stability in phosphate buffer solution with different pH values from 5 to 9, even in the cell culture medium supplied with the fetal bovine serum. Meanwhile, we also studied the interaction of carbon quantum dots with living HeLa cells with confocal microscopy. Our results indicated that the carbon quantum dots can enter the living HeLa cells by cellular penetration.