To understand the mechanisms for selective productions of NO 2 − and NO 3 − as reactive nitrogen species (RNS) in plasma activated water, we studied the oxidation reactions of NO as the primary species supposing O, O 2 , O 3 , OH, and H 2 O 2 as possible oxidants. A coaxial-type dielectric barrier discharge reactor was employed in cascade connection to a reservoir and/or a water bubbler. First, the densities of NO and NO 2 in the gas phase were measured with gas sensors in two gas systems: N 2 admixed with water vapor and N 2 admixed with O 2 , for comparison. It was found that while the density of NO in the latter case was one third of that in the former case owing to the difference in the first-step oxidation to NO 2 or HNO 2 , the total yields of RNS in both cases were comparable. To investigate the oxidation pathways, admixing NO and NO

中文翻译：

---

NO氧化工艺在等离子体活化水中产生活性氮的过程

为了了解在等离子体活化水中选择性产生NO 2-和NO 3-作为活性氮物质（RNS）的机理，我们研究了NO作为主要物质的氧化反应，假设O，O 2，O 3，OH和H 2 O 2为可能的氧化剂。同轴型介电势垒放电反应器用于与储罐和/或注水器的级联。首先，在两个气体系统中使用气体传感器测量气相中NO和NO 2的密度：N 2与水蒸气混合和N 2与O 2混合，以进行比较。结果发现，由于第一步氧化成NO 2或HNO 2的差异，在后一种情况下NO的密度是前一种情况下的三分之一，而在两种情况下RNS的总产率是可比的。为了研究氧化途径，将NO和NO混合