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
The study evaluated the feasibility of using microwave enhanced hot air heating system for simultaneous dry blanching and dehydration of mushroom slices. The technology involves application of microwave energy at the ...The study evaluated the feasibility of using microwave enhanced hot air heating system for simultaneous dry blanching and dehydration of mushroom slices. The technology involves application of microwave energy at the beginning of dehydration process to inactivate enzymes as well as to remove a certain amount of moisture at the same time and then followed by hot air drying to complete the process. The study investigated effects of different processing parameters, i.e., microwave power level and exposure time on dehydration and quality characteristics of mushroom slices. Mushroom slices were pretreated with different microwave power levels of 240, 360 and 480 W for 1, 3 and 5 min before the hot air-drying. The optimum range of the microwave power level and pretreatment time was found to be 360 W, 3 min and 360 W, 1 min in obtaining the maximum and minimum levels of response parameters.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The study evaluated the feasibility of using microwave enhanced hot air heating system for simultaneous dry blanching and dehydration of mushroom slices. The technology involves application of microwave energy at the beginning of dehydration process to inactivate enzymes as well as to remove a certain amount of moisture at the same time and then followed by hot air drying to complete the process. The study investigated effects of different processing parameters, i.e., microwave power level and exposure time on dehydration and quality characteristics of mushroom slices. Mushroom slices were pretreated with different microwave power levels of 240, 360 and 480 W for 1, 3 and 5 min before the hot air-drying. The optimum range of the microwave power level and pretreatment time was found to be 360 W, 3 min and 360 W, 1 min in obtaining the maximum and minimum levels of response parameters.
