Plasma-activated water (PAW) has been utilised in various application fields, and a deep understanding on the plasma chemistry is the foundation of application-orientated optimisation. In this paper, a global model is built to study the chemical properties of PAW produced by a dielectric barrier discharge that is powered by nanosecond voltage pulses. The applied voltage is firstly repeated with 10 kHz frequency for 100 s, and then shut down for 200 s afterglow, providing a long-term evolution regarding the production and consumption of some typical reactive oxygen/nitrogen species (RONS) in PAW. The calculated results agree principally with experimental measurements from literature. During the pulsed discharge, the water gradually acidises, and the long-lived species accumulate; while in the afterglow, most of the aqueous RONS decay rapidly, except for O_3aq, ${\mathrm{NO}}_{\text{3aq}}^{-}$, H₂O_2aq and N₂O_aq, which might be the main sources to sustain long-term effects. Furthermore, the effects of applied voltage and gap distance on RONS are investigated. Correlation analyses from Pearson correlation coefficient indicate that gaseous RONS are more sensitive to the gap distance, while the aqueous ones are more sensitive to the voltage amplitude, suggesting the possibility to independently regulating the gaseous and aqueous chemistry.

中文翻译：

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长时间尺度上等离子体活化水的全局模型：脉冲放电和余辉

等离子体活化水 (PAW) 已被用于各种应用领域，对等离子体化学的深刻理解是面向应用优化的基础。在本文中，建立了一个全局模型来研究由纳秒电压脉冲供电的介质阻挡放电产生的 PAW 的化学性质。施加的电压首先以 10 kHz 的频率重复 100 秒，然后关闭 200 秒的余辉，提供关于 PAW 中一些典型活性氧/氮物种 (RONS) 的生产和消耗的长期演变。计算结果主要与文献中的实验测量结果一致。在脉冲放电期间，水逐渐酸化，长寿物种积累；而在余辉中，大部分水性 RONS 迅速衰减，_3水,${不}_{\text{3aq}}^{-}$, H ₂ O _2aq和 N ₂ O _aq，它们可能是维持长期影响的主要来源。此外，研究了施加电压和间隙距离对 RONS 的影响。Pearson 相关系数的相关分析表明，气态 RONS 对间隙距离更敏感，而水相 RONS 对电压幅度更敏感，表明独立调节气态和水相化学的可能性。