Spectroscopic diagnosis of plasma in atmospheric pressure negative pulsed gas-liquid discharge with nozzle-cylinder electrode

The plasma characteristics of a gas-liquid phase discharge reactor were investigated by optical and electrical methods.The nozzle-cylinder electrode in the discharge reactor was supplied witha negative nanosecond pulsed generator.The optical emission spectrum diagnosis revealed that OH（A2∑＋ → X2Π,306–309 nm）,N32（CΠ→B3Πg,337 nm）,O（3p5p→3s-5s-0,777.2 nm）and O（3p3p→3s3s0,844.6 nm）were produced in the discharge plasma channels.The electron temperature（Te）was calculated from the emission relative intensity ratio between the atomic O 777.2 nm and 844.6 nm,and it increased with the applied voltage and the pulsed frequency and fell within the range of 0.5–0.8 e V.The gas temperature（Tg）that was measured by Lifbase was in a range from 400 K to 600 K.

大气压纳秒负脉冲放电对水中大肠杆菌的灭活

采用自行研制的喷嘴-板-筒式反应器,研究了大气压纳秒负脉冲空气放电对水中大肠杆菌(Escherichia coli,E.coli)灭菌率的影响因素及规律。实验中空气自放电喷嘴电极进入反应器,气流带动放电生成的活性粒子流到达并作用于水中大肠杆菌。研究结果表明:本实验装置可有效实现对水中大肠杆菌的灭活,灭菌率随着放电电压和脉冲重复频率的增加、放电处理时间的延长而升高;随着鼓气速率的增大先增大后减小;随着喷嘴电极直径的增加先减小后增大。当采用1.30 mm喷嘴电极,在脉冲峰值电压为-32 kV、重复频率80 Hz,鼓气速率为80 mL/min时,连续放电处理12 min,灭菌率达到91%。