气体分子对纳米材料硅石气凝胶热传导的影响  

Gas Thermal Conduction of Nano - porous Silica Aerogels

作　　者：张会林[1] 王珏[1] 邓忠生[1] 周斌[1] 

机构地区：[1]同济大学波耳固体物理研究所,上海200092

出　　处：《同济大学学报（自然科学版）》1999年第5期541-544,共4页Journal of Tongji University:Natural Science

基　　金：国家自然科学基金!59802007;上海市启明星后基金!98QME1406

摘　　要：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．In this Paper, we measured the gas thermal conductivity of pure and TiO2 doped silica aerogels at low pressure (<105Pa) by using the transient hot wire method, and researched the affection of the dopant on the gas thermalconductivity of silica aerogels. Considering the thermal motion of the gas molecules confined in the micro - holes of thesilica aerogels, and the scattering between the gas molecules and the solid particles affect the mean the Path of the gasmolecules, we explain the gas thermal conduction in silica aerogels. Both the theory and the experiments show that thedopant increases the gas thermal conductivity of TiO2 doped silica aerogels.

关 键 词：硅石气凝胶 动态热线 气态热导率 二氧化钛 

分 类 号：O648.17[理学—物理化学] TU551.3[理学—化学]