Concentrated sulfuric and concentrated nitric acids treated multi-walled carbon nanotubes(MWNTs) and polystyrene(PS) composites were prepared by solution mixing.Their structures and properties were investigated via TE...Concentrated sulfuric and concentrated nitric acids treated multi-walled carbon nanotubes(MWNTs) and polystyrene(PS) composites were prepared by solution mixing.Their structures and properties were investigated via TEM,FTIR,SEM and DMA.The results showed that acid may also oxidize MWNTs and produce carboxyl groups,which in turn may enhance interaction between polymer and MWNTs.The storage modulus and glass translation tempersture of the comosites can be improved with the increasing of the MWNTs contnet.The composite with 5wt% MWNTs showed its conductivity of an order of 10-3S/cm.展开更多
针对发酵工程实验教学中存在的问题,引入了OBE(Outcomes Based Education)教育理念。本文介绍了OBE教育理念的主要特点和实施的基本过程,探讨了OBE项目教学法在发酵工程实验教学中的应用,主要涉及学习成果的确定、教与学的实施和评估体...针对发酵工程实验教学中存在的问题,引入了OBE(Outcomes Based Education)教育理念。本文介绍了OBE教育理念的主要特点和实施的基本过程,探讨了OBE项目教学法在发酵工程实验教学中的应用,主要涉及学习成果的确定、教与学的实施和评估体系的设计三方面内容。展开更多
文摘Concentrated sulfuric and concentrated nitric acids treated multi-walled carbon nanotubes(MWNTs) and polystyrene(PS) composites were prepared by solution mixing.Their structures and properties were investigated via TEM,FTIR,SEM and DMA.The results showed that acid may also oxidize MWNTs and produce carboxyl groups,which in turn may enhance interaction between polymer and MWNTs.The storage modulus and glass translation tempersture of the comosites can be improved with the increasing of the MWNTs contnet.The composite with 5wt% MWNTs showed its conductivity of an order of 10-3S/cm.