A discharge ignited by an AC power source in contact with deionized water as one of the electrodes is investigated. Immediately after initiation, the discharge exhibits a unique phenomenon: the gas-phase discharge is extended into the liquid. Later, a cone-like structure is observed at the liquid surface. Synchronous monitoring of current–voltage characteristics and liquid properties versus time suggests that the discharge shapes are functions of the liquid properties. The spatio-temporal profiles indicate the potential effects of water, ambient air impurities, and metastable argon on the discharge chemistry. This becomes more obvious near the liquid surface due to increasing production of various transient reactive species such as OH and NO. Moreover, it is revealed that thermalization of the rotational population distributions of the rotational states in the Q ₁ branch of the OH band ro-vibrational system is influenced by the humid environment near the liquid surface. In addition, the transient behaviors of instantaneous concentrations of long-lived reactive species (LRS) such as H₂O₂, and are observed with lengthening the discharge time. The production of multiple transient and LRS proposes AC excited gas–liquid argon discharge as a potential applicant in industrial wastewater cleaning, clinical medicine, and agriculture.

研究了交流电源作为电极之一与去离子水接触引起的放电。启动后，放电立即表现出独特的现象：气相放电扩展到液体中。之后，在液体表面观察到锥形结构。电流-电压特性和液体特性随时间的同步监控表明，放电形状是液体特性的函数。时空分布表明水，环境空气杂质和亚稳氩对放电化学的潜在影响。由于增加了各种瞬态反应性物质（如OH和NO）的产生，这种现象在液面附近变得更加明显。而且，OH波段旋转振动系统的Q ₁分支中，受液面附近潮湿环境的影响。此外，瞬时浓度的瞬态行为长寿命反应性物种（LRS）如H ₂ ö ₂，和与延长放电时间被观察。多种瞬态和LRS的生产建议将AC激发的气液氩排放作为工业废水清洁，临床医学和农业中的潜在申请人。