【摘要】 为了研究纳米气泡接触角小于其宏观接触角这一问题,通过分析醇-水替换前后在高序热解石墨表面上测量得到的力-距离曲线,验证界面气体富集与纳米气泡共存的现象。结合Das提出的杂质与接触角的关系模型,讨论杂质对纳米气泡接触角的影响。根据改进的Young方程分析了线张力降低纳米气泡接触角的机理。结果表明:纳米气泡接触角受界面气体富集、杂质及线张力的影响,纳米气泡接触角小于其宏观接触角是三者共同作用的结果。更多还原

【Abstract】 This paper is aimed at investigating the way the contact angle of surface nanobubbles is smaller than the Young contact angle. The investigation is performed by analyzing from three aspects,such as the interfacial gas enrichment( IGE),line tension and contamination; verifying the phenomenon of coexistence of IGE and nanobubbles by measuring the force-distance curves on highly ordered pyrolytic graphite( HOPG)-liquid surface before and after alcohol-water exchange; discussing the influence of contamination on the contact angle of nanobubble,based on the model of das; and analyzing and identifying the mechanism of line tension reducing the contact angle according to the modified Young equation. The results indicate that surface nanobubbles have a contact angle subjected to the effects of IGE,line tension and contamination and owe their abnormally smaller angle to the combined action of these three facotrs.更多还原