Stable DC atmospheric pressure normal glow discharges in ambient air were produced between the water surface and the metallic capillary coupled with influx of helium gas. Multiple independent repeated trials indicated that vibrational temperature of nitrogen rises from 3200 to 4622 K, and rotational temperature of nitrogen decreases from 1270 to 570 K as gas flux increasing from 20 to 80 sccm and discharge current decreasing from 11 to 3 mA. Furthermore, it was found that the vibrational degree of the nitrogen molecule has priority to gain energy than the rotational degree of nitrogen molecule in nonequilibrium helium microplasma.
Ionization by bulk heating of electrons in capacitive radio frequency atmospheric pressure microplasmas
采用Particle in Cell模拟和半解析模型研究了氦气中大气压下电容耦合射频微等离子体的电子加热和电离动力学。在RF周期内的不同时间观察到由于高体积电场导致的等离子体体积中的电子和电离的强烈加热。基于该模型,确定了该电场是由大气压下高电子-中性粒子碰撞频率导致的低电导率引起的漂移场。因此,在这种“Ω模式”中,电离主要由欧姆加热引起。驱动电压幅值影响最强体电场和电离的相位。在高振幅下,等离子体密度高,使得鞘层阻抗与体电阻相当。因此,电压和电流约为45 °异相,在鞘膨胀期间观察到最大电离,在鞘边缘处具有局部最大值。在低驱动电压下,等离子体密度低并且放电变得更具电阻性,导致约4 °的较小相移。因此,最大电离发生在RF周期内的后期,在放电中心具有最大值。显着的类比电负性低压宏观放电中的漂移双极模式下工作,其中类似的机制引起的高电负性,而不是高碰撞频率已被确定。
Space-resolved characterization of high frequency atmospheric-pressure plasma in nitrogen applying optical emission spectroscopy and numerical simulation
Influence of nitrogen impurities on an electron-excited helium atoms concentration in the self-sustained normal dc glow discharge at atmospheric pressure
Zero-dimensional and pseudo-one-dimensional models of atmospheric-pressure plasma jet in binary and ternary mixtures of oxygen and nitrogen with helium background
Proof of operation of a micro-hollow cathode discharge driven by a true ns-pulsed high voltage: emission properties and atomic nitrogen production
Laboratoire des Sciences des Procédés et des Matériaux (LSPM), CNRS, Université Sorbonne Paris Nord(材料过程与科学实验室,法国国家科学研究中心,索邦巴黎北大学);Laboratoire Energétique Moléculaire et Macroscopique, Combustion (EM2C), CNRS, Université Paris Saclay(分子与宏观能量、燃烧实验室,法国国家科学研究中心,巴黎萨克雷大学)
The role of oxygen and surface reactions in the deposition of silicon oxide like films from HMDSO at atmospheric pressure
本文研究了用六甲基二硅氧烷(HMDSO)和氧气混合气体的大气压微等离子体射流沉积SiO $_x$ C $_y$ H $_z$或SiO $_x$ H $_y$薄膜以及表面反应在薄膜生长中的作用。两种类型的微等离子体射流,一个与平面电极和氦气中操作,另一个与同轴几何操作在氩气中,被用来研究沉积过程。膜的生长速率和膜中的碳含量被测量为平面射流中的O $_2$和HMDSO混合物的函数,并与HMDSO消耗的质谱测量进行比较。此外,本地化的性质的喷射基板相互作用被用来研究表面反应,通过施加两个射流在旋转基板上。向气体混合物中添加氧气增加HMDSO耗尽和生长速率,并导致无碳膜的沉积。表面反应负责从生长的膜中去除碳。此外,当用氩气操作的同轴射流用于表面处理时,甚至在不添加氧气的情况下也可以沉积无碳膜。我们假设,离子或激发物种(可吸收)可能是负责观察到的效果。
Synergistic control of radical generation in a radio frequency atmospheric pressure plasma jet via voltage waveform tailoring and structured electrodes
Sustainable improvement of seeds vigor using dry atmospheric plasma priming: evidence through coating wettability, water uptake and plasma reactive chemistry