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以动态热线法测量不同气压下纯硅石气凝胶和ＴｉＯ２掺杂硅石气凝胶的气态热导率，研究ＴｉＯ２掺杂对硅石气凝胶气态热传导的影响．实验结果表明，硅石气凝胶的微孔洞中气体分子热运动受限，考虑气体分子间、气体分子与团体颗粒间碰撞对气体分子平均自由程影响的气态热传导理论能很好地解释实验现象，理论和实验都表明，ＴｉＯ２掺杂使硅石气凝胶的气态热导率变大．
The dynamic thermal line method was used to measure the gaseous thermal conductivity of pure silica airgel and TiO2-doped silica aerogels at different pressures, and the effect of TiO2 doping on the gaseous heat conduction of silica aerogels was investigated. The experimental results show that the thermal motion of gas molecules in the micropore of silica aerogels is limited. The gaseous heat conduction theory, which considers the influence of gas molecules, gas molecules and group particles on the mean free path of gas molecules, can well explain the experimental phenomena Both theoretical and experimental results show that the doping of TiO2 increases the thermal conductivity of silica aerogels.