有许多种方法可用于在大气中产生等离子体射流,冷等离子体(离子温度在室温附近)射流即是其中的一种.近年来,人们发现氦气或其它惰性气体通过毛细管介质阻挡放电形成的冷等离子体射流具有类似子弹的传输特性,在有机材料表面改性、等离子体医学等领域获得了广泛的应用.通过专门设计的一系列实验,我们逐渐揭示了其产生机理,并深入研究了传输特性.文章简要介绍近年来我们所做的有关大气压冷等离子体的实验过程以及获得的一些重要结论.在对这种等离子体深入了解的基础上,作者还开发了一种新装置,该装置的最大特点是既利用了氦气在辅助放电方面的特性,又不消耗这种昂贵的资源;并且它还特别适合于在臭氧层修复、等离子体医学等方面的应用.
Various plasma jets have been produced by using different designs,which can protrude into the ambient air for centimeters.Cold plasma jets are one of such plasma jet,with 'cold' here we mean that the ion temperature is roughly the room temperature.It has been found that the helium (or other inert gas) atmospheric pressure plasma jet (APPJ) which was believed to be produced via dielectric barrier discharge (DBD) blows plasma-bullets into the plume,and such a jet promises various applications in polymer surface modification,plasma medicine and so on.However,the generation mechanism and transport properties of APPJ are far from being well clarified.In the past a few years,we gradually revealed the veil over this interesting plasma phenomenon.In this paper a brief summary over our work in this field is presented.Besides some discussion over the mechanism of APPJ and the interplay between gas flow and plasma plume therein,also a new device is described,of which the most interesting feature is that it employs the profitable property of the inert gas for plasma generation,yet without consuming a bit of it.The results can promote the applications of APPJ in material processing,ozone generation,plasma medicine and many other fields.