对氦气介质阻挡放电等离子体和氦气毛细管介质阻挡放电冷等离子体射流失活酵母菌的效率和机制进行了比较研究.分析比较了两种等离子体处理的菌液存活曲线和pH值的变化情况;利用扫描电子显微镜观察了菌体表面超微结构的变化.结果显示两...对氦气介质阻挡放电等离子体和氦气毛细管介质阻挡放电冷等离子体射流失活酵母菌的效率和机制进行了比较研究.分析比较了两种等离子体处理的菌液存活曲线和pH值的变化情况;利用扫描电子显微镜观察了菌体表面超微结构的变化.结果显示两种等离子体对酵母菌均有较强的杀灭作用,介质阻挡放电等离子体处理5 m in后可使其减少约7个数量级,而毛细管介质阻挡放电冷等离子体射流处理后可使其减少约8个数量级;同时经过两种等离子体处理后的pH值均明显下降,且毛细管介质阻挡放电冷等离子体射流处理菌液的pH下降幅度大于介质阻挡放电等离子体处理的菌液;从扫描电子显微镜的照片可以看到两种等离子体处理后的菌体均已破裂.实验结果表明毛细管介质阻挡放电冷等离子体射流失活酵母菌的效率要高于介质阻挡放电等离子体,并且杀菌机理应该与细胞破裂及pH值的变化有关.展开更多
Non-thermal plasma jet at atmospheric pressure has recently attracted lots of attention because of its applications in plasma bullet or plasma plume.Thus,we studied on generating plasma jet by coplanar dielectric barr...Non-thermal plasma jet at atmospheric pressure has recently attracted lots of attention because of its applications in plasma bullet or plasma plume.Thus,we studied on generating plasma jet by coplanar dielectric barrier discharge in a device driven by sinusoidal voltage.The processes of plasma discharges in both positive and negative half cycles were recorded using a high-speed ICCD(intensified charge-coupled device)camera;based on the results we estimated the velocity of plasma propagation,and investigated the influence of gas flow on the plasma development.It is shown that the plasma bullets,which have velocity in the order of 103~104m/s,exist only outside the cathode.APPJ(atmospheric pressure plasma jet)is created by the electron beam from the cathode,and then sustained by a strong radial electric field near and outside the cathode.The gas flow influences the APPJ length in air but not the APPJ discharge,while the discharge is affected significantly by the applied voltage.展开更多
文摘对氦气介质阻挡放电等离子体和氦气毛细管介质阻挡放电冷等离子体射流失活酵母菌的效率和机制进行了比较研究.分析比较了两种等离子体处理的菌液存活曲线和pH值的变化情况;利用扫描电子显微镜观察了菌体表面超微结构的变化.结果显示两种等离子体对酵母菌均有较强的杀灭作用,介质阻挡放电等离子体处理5 m in后可使其减少约7个数量级,而毛细管介质阻挡放电冷等离子体射流处理后可使其减少约8个数量级;同时经过两种等离子体处理后的pH值均明显下降,且毛细管介质阻挡放电冷等离子体射流处理菌液的pH下降幅度大于介质阻挡放电等离子体处理的菌液;从扫描电子显微镜的照片可以看到两种等离子体处理后的菌体均已破裂.实验结果表明毛细管介质阻挡放电冷等离子体射流失活酵母菌的效率要高于介质阻挡放电等离子体,并且杀菌机理应该与细胞破裂及pH值的变化有关.
基金Project supported by National Natural Science Foundation of China (10875010 11175017).
文摘Non-thermal plasma jet at atmospheric pressure has recently attracted lots of attention because of its applications in plasma bullet or plasma plume.Thus,we studied on generating plasma jet by coplanar dielectric barrier discharge in a device driven by sinusoidal voltage.The processes of plasma discharges in both positive and negative half cycles were recorded using a high-speed ICCD(intensified charge-coupled device)camera;based on the results we estimated the velocity of plasma propagation,and investigated the influence of gas flow on the plasma development.It is shown that the plasma bullets,which have velocity in the order of 103~104m/s,exist only outside the cathode.APPJ(atmospheric pressure plasma jet)is created by the electron beam from the cathode,and then sustained by a strong radial electric field near and outside the cathode.The gas flow influences the APPJ length in air but not the APPJ discharge,while the discharge is affected significantly by the applied voltage.