Fe3O4 catalyst supported on spherical γ-Al2O3 was prepared with and without ultrasonic treatment during the impregnation step,and the heterogeneous catalytic oxidation of dimethoate wastewater was conducted with Fent...Fe3O4 catalyst supported on spherical γ-Al2O3 was prepared with and without ultrasonic treatment during the impregnation step,and the heterogeneous catalytic oxidation of dimethoate wastewater was conducted with Fenton reagent.Then,the physical and chemical properties of the catalysts were analyzed by means of XRD,ICP-AES and SEM,especially the effect of Fe3O4 dispersity on γ-Al2O3.The results showed that the activity of the supported catalysts prepared with ultrasonic treatment for dimethoate was higher than those without ultrasonic treatment and the corresponding degradation rate doubled those of the catalyst obtained by impregnation.The probable cause was that for catalysts prepared with ultrasonic treatment,Fe3O4 was well dispersed on the catalyst surface with small particle size,or existed in non-crystalline amorphous state,and Fe content on the catalyst surface was higher than those without ultrasonic treatment.展开更多
为研究不同功率超声辅助浸渍冷冻对牛肉品质的影响,选取传统风冷和0、200、400、600 W 4组不同功率超声波辅助冷冻处理牛肉,以鲜肉组为对照,分析其冻结速率、蒸煮损失、解冻损失、嫩度、色差值、水分分布和微观结构等变化情况。结果表明...为研究不同功率超声辅助浸渍冷冻对牛肉品质的影响,选取传统风冷和0、200、400、600 W 4组不同功率超声波辅助冷冻处理牛肉,以鲜肉组为对照,分析其冻结速率、蒸煮损失、解冻损失、嫩度、色差值、水分分布和微观结构等变化情况。结果表明:超声波辅助可以提升牛肉的冻结速率,影响牛肉色泽和水分状态,减轻冷冻过程中肌肉组织结构破坏和品质劣变。当超声波功率为400 W时,牛肉冻结速率最快,且蒸煮损失和解冻损失最低,分别为32.44%和1.66%,剪切力与鲜肉组也最为接近;另外,功率400 W时冷冻牛肉可冻结水质量分数最小,为51.11%;低场核磁分析表明,T21振幅最大,T22振幅变化较小,水分分布也更加均匀;微观结构观察显示,适当的功率超声辅助处理下,能减少冷冻过程对肌纤维及组织网络结构的破坏,从而改善冷冻肉的品质。展开更多
文摘Fe3O4 catalyst supported on spherical γ-Al2O3 was prepared with and without ultrasonic treatment during the impregnation step,and the heterogeneous catalytic oxidation of dimethoate wastewater was conducted with Fenton reagent.Then,the physical and chemical properties of the catalysts were analyzed by means of XRD,ICP-AES and SEM,especially the effect of Fe3O4 dispersity on γ-Al2O3.The results showed that the activity of the supported catalysts prepared with ultrasonic treatment for dimethoate was higher than those without ultrasonic treatment and the corresponding degradation rate doubled those of the catalyst obtained by impregnation.The probable cause was that for catalysts prepared with ultrasonic treatment,Fe3O4 was well dispersed on the catalyst surface with small particle size,or existed in non-crystalline amorphous state,and Fe content on the catalyst surface was higher than those without ultrasonic treatment.
文摘为研究不同功率超声辅助浸渍冷冻对牛肉品质的影响,选取传统风冷和0、200、400、600 W 4组不同功率超声波辅助冷冻处理牛肉,以鲜肉组为对照,分析其冻结速率、蒸煮损失、解冻损失、嫩度、色差值、水分分布和微观结构等变化情况。结果表明:超声波辅助可以提升牛肉的冻结速率,影响牛肉色泽和水分状态,减轻冷冻过程中肌肉组织结构破坏和品质劣变。当超声波功率为400 W时,牛肉冻结速率最快,且蒸煮损失和解冻损失最低,分别为32.44%和1.66%,剪切力与鲜肉组也最为接近;另外,功率400 W时冷冻牛肉可冻结水质量分数最小,为51.11%;低场核磁分析表明,T21振幅最大,T22振幅变化较小,水分分布也更加均匀;微观结构观察显示,适当的功率超声辅助处理下,能减少冷冻过程对肌纤维及组织网络结构的破坏,从而改善冷冻肉的品质。
