Photo ionization plays a critical role in the formation and propagation of atmospheric pressure plasma jet plumes. But in experiments, it is very difficult to observe the photo ionization due to its relative lower density of photo electrons. In the present study, we develop a portable cold air plasma jet device and observe the ionization wave in a dc spark air plasma jet. The discharge images acquired by an ICCD camera show that the ionization wave front performs as a quickly moving bright ball. Breakdown could take place at another side of the quartz plate or pork tissue layer (6 mm thick), which suggests that the ionization should be attributed to photo ionization. The laser schlieren images indicate there is propagation of a shock wave along with the plasma bullet. Based on the photo ionization theory and the photo-electric measurement, the direct photo ionization and multistage photo ionization are the main factors in charge of generating the cold air plasma jet. In addition...

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便携式冷空气等离子体射流装置的研制及其光电离过程的观察

光电离在大气压等离子体射流的形成和传播中起着至关重要的作用。但是在实验中，由于光电子的相对较低密度，很难观察到光离子化。在本研究中，我们开发了一种便携式冷空气等离子体射流装置，并在直流火花空气等离子体射流中观察了电离波。由ICCD摄像机获取的放电图像显示，电离波阵面表现为快速移动的明亮球。击穿可能发生在石英板或猪肉薄纸层（6毫米厚）的另一侧，这表明电离应归因于光电离。激光纹影图像表明，冲击波与等离子子弹一起传播。基于光电离理论和光电测量，直接光电离和多级光电离是产生冷空气等离子体射流的主要因素。此外...