摘要
There are still fundamental problems lying in the basic research of bulk nanobubbles.Are the bulk nanobubbles reported in the literature nano scale bubbles or contaminants in fact?At present,there is not yet sufficient experimental evidence to show that the bulk nanoparticles are only gas bubbles but not other nano scale contaminants.If they are indeed nanobubbles,what causes the bulk nanobubbles observed in the literature to be much more stable than being predicted by the Epstein-Plesset theory?This paper firstly discusses the contradiction between the traditional theory prediction and the observed lifetime of the bulk nanobubbles,and then discusses whether the so-called nanobubbles are gas aggregates.We review the existing typical models,and the influence of different conditions on the stability of bulk nanobubbles,for paving the road to a clear understanding of the stability mechanism of bulk nanobubbles.In addition,the representative production methods and characterization methods of bulk nanobubbles are discussed in order to offer some guidance to their wide range of commercial applications.
基金
Financial support from the Ministry of Science and Technology,China(No.ZK20210004)
the Department of Science and Technology of Shandong Province,China(No.ZK20200026),are gratefully acknowledged.
