| The existence of nanobubbles was just emerging up recently and the proposed existence of nanobubble was around 20 years. At first, many people denied the possibility of the existence of nanometer bubbles, and now it has almost reached a consent that nanobubbles are present at the interface and relevant to many surface phenomena. All the evidence above could just prove the presence of nanaobubbles in an indirect way. The evidence searching made a breakthrough in 2000 and 2001 when AFM images of nanobubbles were published. After that, the presence of nanobubble was proven further by the measurements of neutron reflectivity. Meanwhile, the studies found that through degassing method using Freeze-Pump-Thaw(F-P-T) process could remove the dissolved gas and nano bubbles. Till now, there were controversial issues on the nanobubbles, including the sources and the topography of nanobubbles. As for the formation and the properties of nanobubbles, they have not been touched up to now.At present for its strongpoint of imaging with nanometer resolution and measuring force with sub-piconewton resolution, tapping-mode AFM imaging in fluid has provided visual evidence of the presence of nanobubbles at solid/liquid interface. Unfortunately, except for morphological information and mechanical characteristics of nanobubbles, it was difficult for AFM to reveal nanobubbles qualitatively. In this study , by exchanging ethanol and water in a repeatable way, nanobubbles were formed at hydrophilic mica/water interface. The influences of image conditions and de-aeration on nanobubbles were investigated. The nanobubbles were observed by tapping mode AFM in fluid , but were too fragile to be observed by using contact mode and susceptible to deformation and destruction by the force from tapping mode AFM. Degassing ethanol and water reduced the amounts and the formation possibility of nanobubbles. It was concluded that the dissolved gas was the origin of the nanobubbles on mica surface formed by the exchange of ethanol and water. Furthermore, the change of the amounts and the formation possibility of nanobubbles with the quantity of dissolved gas in liquid was a qualitative evidence of the existence of nanobubbles and nanofilms at solid/liquid interface. But the lack of AFM was unable to qualitative, the characteristics of morphology observed what materials could not be determined. Using soft X-ray Testing Technology(STXM), the measurement ofOxygen nanobbles in the K absorption spectrum compared with the oxygen absorpti--on spectrum, Combining the stack and dual-energy chemical element analysis, it could make up for lack of AFM.This paper studied the accumulation of oxygen micro/nanobubbles on hydrophobic surfaces in water. The solid/liquid sol samples were prepared by dispersing particles into deeply degassed water. The pure oxygen was pumped into sol samples for producing micro/nanobubbles on the particles surfaces. STXM and the determination of Dissolved Oxygen had application in the measurement for the samples. The test results of STXM was further verified that the real existence of nanobubbles. Dissolved oxygen test results indicated that, micro/nanobubbles enriched the oxygen of water significantly, especially in the magnetic stirring, ultrasonic treatment conditions, the dissolved oxygen in water increased rapidly.The presence, properties and applications of nanobubbles were worth to explore, In this paper, firstly, the existence of nano-bubbles was further verified. Then made a preliminary study on water restoration . The super micro bubble water repair technology was the most advanced international technology, now research on nanoscale bubble repairing technology was very few, this technique can effectively solve the current social water pollution problems, as it is purely physical methods used to solve the problems of water pollution and which could not be formed in the process of secondary pollution. |
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