改性SiO2载体对邻菲咯啉钌荧光特性及氧敏感荧光膜性能的影响

为提高极性荧光指示剂Ru(dpp)₃Cl₂在非极性硅橡胶中的分散性,以沉淀白炭黑、气相白炭黑和甲基MQ树脂,载负荧光指示剂Ru(dpp)₃Cl₂,再填充到二甲基硅橡胶(PDMS)中,制备氧敏感荧光膜.以分光光度计和荧光光谱仪,研究载体种类对Ru(dpp)₃Cl₂的吸附性、荧光特性及氧敏感荧光膜性能的影响.白炭黑载负Ru(dpp)₃Cl₂的荧光发射光谱相对其稀溶液约红移20 nm.载体表面的甲基可减弱SiO₂载体对Ru(dpp)₃Cl₂分子的吸附性和相互作用,减少荧光发射光谱的红移12 nm,提高荧光强度近10倍.白炭黑有助改善Ru(dpp)₃Cl₂在PDMS中的分散性和氧敏感荧光膜的荧光输出和猝灭比,尤以MQ树脂的效果最为显著.     

荧光指示剂载体对荧光法溶氧传感器荧光膜性能的影响

以沉淀白炭黑、气相白炭黑和MQ树脂负载荧光指示剂Ru(dpp)3Cl2,添加到二甲基硅橡胶,制备氧敏感荧光膜,研究指示剂载体和用量对荧光膜荧光输出的影响。结果表明:纯硅橡胶荧光膜的荧光输出很低,SiO2填料可作荧光指示剂的载体提高指示剂的分散和荧光效率,SiO2填料提高荧光效率的能力为MQ树脂>气相白炭黑>沉淀白炭黑。含10%SiO2载体的硅橡胶制备的荧光膜,其荧光输出随指示剂用量线性增加,直至指示剂用量达0.1%,但SiO2填料降低荧光膜的响应速度。     

Directional Motion of Droplets in a Conical Tube or on a Conical Fibre

Manipulating the directional movement of liquid droplets is of significance for design and fabrication of some microfluidic devices, An energy-based method is adopted to analyse the directional movement of a droplet deposited in a conical tube or on a conical fibre. We perform an experiment to investigate the directional motion of a droplet in an open conical tube. Our theoretical analysis and experimental observations both demonstrate that surface tension can drive the droplet to move in the conical tube. The critical condition of the liquid moving in the conical tube is presented. We also analyse a droplet on a conical hydrophilic fibre, which can move from the thinner to the thicker end.