二氧化硅@聚合物同轴纳米纤维

The preparation and formation mechamsm ot silica/polyvinylpyrrolidone(PAN) coaxial nanofibers were presented in this paper. The PVP-PAN composite nanofibers were obtained via an electrospinning technique, while SiO2 nanoparticles were prepared according to a Stoeher method. The measurements of water contact angle(WCA), the compared results of silica coating PVPPAN composite nanofibers with PAN nanofibers indicate that much PVP resided on the composite nanofiber surface, which resuks in the occurrence of SiO2@polymer coaxial nanofibers due to the formation of hydrogen bonding between silica and composite nanofibers and subsequent adsorption of silica on the fiber surface.     

聚丙烯腈纳米纤维的再细化

通过电纺丝法研究了溶剂种类、溶液浓度、纺丝倾斜角、聚合物分子量对纳米纤维形态和直径的影响,寻找到最佳工艺条件,并得到了平均直径为20nm的超细纤维.     

Preparation of Functional Gradient Material n-PbTe with Continuous Carrier Concentration

Functional gradient materials （FGMs） in thermoelectric materials can raise the maximal power output of the thermoelectric generator （TEG）. We report an FGM of n-PbTe with continuous carrier concentration successfully prepared by a unidirectional solidification method. The continuous carrier concentration for n-Pb Te was optimized by different dopants of PbI2, Al and Zr and solidifying temperature. The effective maximum outputting power for continuous FGM PbTe is about 30% larger than that for jointed FGM PbTe.