从确定性到随机性的黏附接触理论

发布时间：2017-12-31 08:30

  本文关键词：从确定性到随机性的黏附接触理论　出处：《科学通报》2016年07期 　论文类型：期刊论文

  更多相关文章： 黏附 接触力学 纳米颗粒 热涨落 随机脱黏

【摘要】：胶体、药物输运、细胞-病毒等体系中广泛涉及纳米颗粒与弹性固体表面之间的黏附相互作用.本文简要回顾了黏附接触理论的发展历史:已有的确定性黏附接触理论(如JKR,DMT等模型)预测,颗粒在低于临界分离拉力的作用下不会与基底分离,这一结论在颗粒特征尺寸减小到纳米尺度时不再适用.研究表明:当纳米颗粒与固体表面黏附的能量尺度接近环境热噪声的特征能量时,其界面黏附呈现出显著的尺寸效应和由此导致的随机性.基于经典的Kramers理论,建立了统计的黏附接触理论,将纳米颗粒与固体表面的黏附状态演化视为广义扩散过程,并用黏附寿命的概率分布描述黏附界面的相对强弱.两个纳米颗粒同时与弹性固体表面作用时,二者的黏附状态呈现明显的时空关联,可通过改变其中一颗粒的状态,间接调控另一颗粒的黏附寿命.
[Abstract]:Colloid, drug delivery. The adhesion interaction between nanoparticles and elastic solid surfaces is widely involved in cell-virus systems. The history of adhesion contact theory is briefly reviewed in this paper. Like JKR. DMT et al.) it is predicted that particles will not be separated from the substrate under the action of lower critical separation tension. This conclusion is no longer applicable when the particle characteristic size is reduced to nanometer scale. The results show that when the energy scale of the adhesion between nanoparticles and solid surface is close to the characteristic energy of ambient thermal noise. The interfacial adhesion shows significant size effect and randomness. Based on the classical Kramers theory, the statistical adhesion contact theory is established. The adhesion state evolution between nanoparticles and solid surfaces is regarded as a generalized diffusion process, and the relative strength of the adhesion interface is described by the probability distribution of the adhesion life. When the two nanoparticles interact with the elastic solid surface at the same time. The adhesion state of the two particles is spatially and temporally related, and the adhesion life of the other particle can be indirectly regulated by changing the state of one of the particles.
【作者单位】： 浙江大学航空航天学院应用力学研究所;香港大学机械工程系;
【基金】：国家自然科学基金(11202184,11321202)资助
【分类号】：O343.3
【正文快照】： 1黏附接触理论发展历史接触力学的起源可以追溯到1882年,Hertz[1]在研究通过机械力改变材料光学性质的过程中,发现玻璃球与棱镜的接触区域出现了椭圆形的牛顿环,由此推断并验证了玻璃球对棱镜的压力分布为椭圆型分布.在经典弹性力学体系下,Hertz接触模型可解析的应用于球体与，

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