为探究纳米膜和PVC膜对西兰花的保鲜作用,分别采用0.03 mm厚的纳米膜、PVC膜和0.04 mm PE膜(CK)包装西兰花,于常温下贮藏,对其感官、生理指标和营养指标进行测定。结果表明:室温下贮藏,纳米膜和PVC膜包装有效延缓了西兰花外观品质、水分...为探究纳米膜和PVC膜对西兰花的保鲜作用,分别采用0.03 mm厚的纳米膜、PVC膜和0.04 mm PE膜(CK)包装西兰花,于常温下贮藏,对其感官、生理指标和营养指标进行测定。结果表明:室温下贮藏,纳米膜和PVC膜包装有效延缓了西兰花外观品质、水分及TSS、V_C、叶绿素等营养物质含量的下降;纳米膜和PVC膜包装可显著抑制西兰花的黄化及MDA积累,增强西兰花POD和CAT活性。这说明纳米膜和PVC膜包装对西兰花的保鲜效果有显著影响,PVC膜包装的西兰花保鲜效果更好。展开更多
TiO2/glass film was prepared by a solgel method with titanium tetrabutoxide as precursor,and used in photocatalytic degradation of 4Chlorophenol(4CP)in aqueous solution.The crystal type and size of TiO2 in f...TiO2/glass film was prepared by a solgel method with titanium tetrabutoxide as precursor,and used in photocatalytic degradation of 4Chlorophenol(4CP)in aqueous solution.The crystal type and size of TiO2 in film prepared in different experimental conditions were characterized by using XRD.The experiments indicated that the TiO2 particles in different film appear regular anatase structure with size about 833nm after heating treatment at 500℃ temperature,and the film coated 5 layers of TiO2 sol in the case of higher(pH≥10)and lower pH value(pH≤2) showed a higher catalytic activity.The relationship between initial 4CP concentration(C0) and reaction rate(r0) follow LangmuirHinshelwood equation,and the photocatalytic degradation of 4CP(C0≤07mmol·L-1)can be expressed by first order kinetics.展开更多
采用电沉积方法在表面活性剂与电解液的界面上制备了银纳米膜。通过对甲磺酸银体系和硝酸银体系中纳米银膜的电沉积速率及纳米银膜颗粒进行比较发现,相同条件下硝酸银体系得到的纳米膜晶粒粒径比较小,膜的生长速率较快。选定硝酸银体系...采用电沉积方法在表面活性剂与电解液的界面上制备了银纳米膜。通过对甲磺酸银体系和硝酸银体系中纳米银膜的电沉积速率及纳米银膜颗粒进行比较发现,相同条件下硝酸银体系得到的纳米膜晶粒粒径比较小,膜的生长速率较快。选定硝酸银体系为电沉积体系。考察了槽压、电解液的浓度和温度及溶液的pH值对制备银纳米膜的影响,确立了制备银纳米膜的最佳工艺条件为硝酸银浓度5 mm o l/L,槽压4 V,pH 3.0,硬脂酸的质量浓度0.2 g/L。实验表明,最佳工艺条件下制备的银纳米膜晶粒粒径均匀,平均粒径在20 nm左右,近似球形。本方法制备的银纳米膜将在非线性光学材料方面得到应用。展开更多
文摘为探究纳米膜和PVC膜对西兰花的保鲜作用,分别采用0.03 mm厚的纳米膜、PVC膜和0.04 mm PE膜(CK)包装西兰花,于常温下贮藏,对其感官、生理指标和营养指标进行测定。结果表明:室温下贮藏,纳米膜和PVC膜包装有效延缓了西兰花外观品质、水分及TSS、V_C、叶绿素等营养物质含量的下降;纳米膜和PVC膜包装可显著抑制西兰花的黄化及MDA积累,增强西兰花POD和CAT活性。这说明纳米膜和PVC膜包装对西兰花的保鲜效果有显著影响,PVC膜包装的西兰花保鲜效果更好。
文摘TiO2/glass film was prepared by a solgel method with titanium tetrabutoxide as precursor,and used in photocatalytic degradation of 4Chlorophenol(4CP)in aqueous solution.The crystal type and size of TiO2 in film prepared in different experimental conditions were characterized by using XRD.The experiments indicated that the TiO2 particles in different film appear regular anatase structure with size about 833nm after heating treatment at 500℃ temperature,and the film coated 5 layers of TiO2 sol in the case of higher(pH≥10)and lower pH value(pH≤2) showed a higher catalytic activity.The relationship between initial 4CP concentration(C0) and reaction rate(r0) follow LangmuirHinshelwood equation,and the photocatalytic degradation of 4CP(C0≤07mmol·L-1)can be expressed by first order kinetics.
文摘采用电沉积方法在表面活性剂与电解液的界面上制备了银纳米膜。通过对甲磺酸银体系和硝酸银体系中纳米银膜的电沉积速率及纳米银膜颗粒进行比较发现,相同条件下硝酸银体系得到的纳米膜晶粒粒径比较小,膜的生长速率较快。选定硝酸银体系为电沉积体系。考察了槽压、电解液的浓度和温度及溶液的pH值对制备银纳米膜的影响,确立了制备银纳米膜的最佳工艺条件为硝酸银浓度5 mm o l/L,槽压4 V,pH 3.0,硬脂酸的质量浓度0.2 g/L。实验表明,最佳工艺条件下制备的银纳米膜晶粒粒径均匀,平均粒径在20 nm左右,近似球形。本方法制备的银纳米膜将在非线性光学材料方面得到应用。