Influence of water content on the inactivation of P. digitatum spores using an air–water plasma jet  

作　　者：胡友谊 朱卫东 刘坤 韩冷 郑振峰 胡慧敏 

机构地区：[1]The State Key Laboratory of Power Transmission Equipment & System Security and New Technology,Chongqing University, No. 174 Shazheng Street, Shapingba, Chongqing 400044, People's Republic ofChina [2]Saint Peter's University, Jersey City, NJ 07306, United States of America [3]The Citrus Research Institute, Chinese Academy of Agricultural Sciences, Chongqing 400712, People'sRepublic of China

出　　处：《Plasma Science and Technology》2018年第4期71-77,共7页等离子体科学和技术（英文版）

基　　金：supported by National Natural Science Foundation of China (NSFC) under Grants No. 51407020;National Key Technology Research and Development Program of the Ministry of Science and Technology of China under Grants No. 2014BAC13B05;Visiting Scholarship of State Key Laboratory of Power Transmission Equipment & System Security and New Technology (Chongqing University) No. 2007DA10512716404

摘　　要：In order to investigate whether an air–water plasma jet is beneficial to improve the efficiency of inactivation, a series of experiments were done using a ring-needle plasma jet. The water content in the working gas（air） was accurately measured based on the Karl Fischer method. The effects of water on the production of OH（A;Σ;–X;Π;） and O（3p;P–3s;S） were also studied by optical emission spectroscopy. The results show that the water content is in the range of 2.53–9.58 mg l;, depending on the gas/water mixture ratio. The production of OH（A;Σ;–X;Π;） rises with the increase of water content, whereas the O（3p;P–3s;S） shows a declining tendency with higher water content. The sterilization experiments indicate that this air–water plasma jet inactivates the P. digitatum spores very effectively and its efficiency rises with the increase of the water content. It is possible that OH（A;Σ;–X;Π;） is a more effective species in inactivation than O（3p;P–3s;S） and the water content benefit the spore germination inhibition through rising the OH（A;Σ;–X;Π;） production. The maximum of the inactivation efficacy is up to 93% when the applied voltage is -6.75 kV and the water content is 9.58 mg l;.In order to investigate whether an air–water plasma jet is beneficial to improve the efficiency of inactivation, a series of experiments were done using a ring-needle plasma jet. The water content in the working gas(air) was accurately measured based on the Karl Fischer method. The effects of water on the production of OH(A^2Σ^+–X^2Π_i) and O(3p^5P–3s^5S) were also studied by optical emission spectroscopy. The results show that the water content is in the range of 2.53–9.58 mg l^(-1), depending on the gas/water mixture ratio. The production of OH(A^2Σ^+–X^2Π_i) rises with the increase of water content, whereas the O(3p^5P–3s^5S) shows a declining tendency with higher water content. The sterilization experiments indicate that this air–water plasma jet inactivates the P. digitatum spores very effectively and its efficiency rises with the increase of the water content. It is possible that OH(A^2Σ^+–X^2Π_i) is a more effective species in inactivation than O(3p^5P–3s^5S) and the water content benefit the spore germination inhibition through rising the OH(A^2Σ^+–X^2Π_i) production. The maximum of the inactivation efficacy is up to 93% when the applied voltage is -6.75 kV and the water content is 9.58 mg l^(-1).

关 键 词：air–water plasma jet water content inactivation efficiency P. digitatum spores OH(A2Σ+–X2Πi) O(3p5P–3s5S) 

分 类 号：O53[理学—等离子体物理]