# Influence of Oxygen Impurity on Nitrogen Atmospheric-Pressure Plasma Jet
## 2 Materials and Methods
\begin{table}
\begin{tabular}{l c c c} \hline \hline \multicolumn{1}{c}{**k**} & \multicolumn{1}{c}{**Reaction**} & \multicolumn{1}{c}{**Reaction Rate \({}^{*}\)**} & **Reference** \\ \hline k1 & e+N\({}_{2}\)\(\rightarrow\)2N+e & \(1.249\times 10^{-10}\times(11608\times\mathrm{Te})^{0.49}\times\mathrm{e}^{-1.6 \times 10^{5}/11608\times\mathrm{Te}}\) & [31; 32] \\ k2 & e+N\({}_{2}\)\(\rightarrow\)N\({}_{2}\)(A)+e & \(1.23\times 10^{-6}\times(11608\times\mathrm{Te})^{-0.47}\times\mathrm{e}^{-1.0 \times 10^{5}/11608\times\mathrm{Te}}\) & [31; 32] \\ k3 & e+N\({}_{2}\)\(\rightarrow\)N\({}_{2}\)(B)+e & \(4.06\times 10^{-5}\times(11608\times\mathrm{Te})^{-0.74}\times\mathrm{e}^{-1.1 7\times 10^{5}/11608\times\mathrm{Te}}\) & [31; 32] \\ k4 & e+N\({}_{2}\)\(\rightarrow\)N\({}_{2}\)(C)+e & \(8.3\times 10^{-11}\times(1.5\times\mathrm{Te})^{2}\times\mathrm{e}^{-3.43/ \mathrm{Te}}\) & [31; 32] \\ k5 & e+N\({}_{2}\)\(\rightarrow\)N\({}_{2}\)(a)+e & \(1.85\times 10^{-11}\times(1.5\times\mathrm{Te})^{1.5747}\times\mathrm{e}^{-2.3658/ \mathrm{Te}}\) & [31; 32] \\ k6 & N\({}_{2}\)\(\rightarrow\)N\({}_{2}\)(A)+N & \(1.2\times 10^{-12}\times\mathrm{Te}^{-1.5}\times\mathrm{e}^{-6.2/ \mathrm{Te}}\) & [33] \\ \hline k7 & N+N+M\(\rightarrow\)N\({}_{2}\)+M, M=N\({}_{2}\), 100–600 K & \(8.3\times 10^{-34}\times\mathrm{e}^{600/\mathrm{T}}\) & [34] \\ k8 & N+N+M\(\rightarrow\)N\({}_{2}\)+M, M=N\({}_{2}\), 600–6300 K & \(1.91\times 10^{-33}\) & [34] \\ k9 & 100–400 K & \(1.8\times 10^{-33}\times\mathrm{e}^{435/\mathrm{T}}\) & [34] \\ k10 & N+N+M\(\rightarrow\)N\({}_{2}\)+M, M=O, N & \(5.4\times 10^{-33}\times\mathrm{e}^{435/\mathrm{T}}\) & [34] \\ k11 & N\({}_{2}\)+M\(\rightarrow\)N+N+M, M=O\({}_{2}\), NO, N\({}_{2}\) & \(5.4\times 10^{-8}\times\left(1-\mathrm{e}^{-3354/\mathrm{T}}\right)\times\mathrm{e}^{-1 13200/\mathrm{T}}\) & [34] \\ k12 & N\({}_{2}\)+M\(\rightarrow\)N+N+M, M=O, N & \(3.564\times 10^{-7}\times\left(1-\mathrm{e}^{-3354/\mathrm{T}}\right)\times\mathrm{e}^{-1 13200/\mathrm{T}}\) & [34] \\ k13 & N\({}_{2}\)+N+N\(\rightarrow\)N\({}_{2}\)(A)+N\({}_{2}\) & \(8.27\times 10^{-34}\times\mathrm{e}^{500/\mathrm{T}}\) & [32] \\ k14 & N\({}_{2}\)(A)+N\({}_{2}\)\(\rightarrow\)N\({}_{2}\)+N\({}_{2}\) & \(4\times 10^{-17}\) & [32; 33; 35] \\ k15 & N\({}_{2}\)(A)+N\({}_{2}\)\(\rightarrow\)N\({}_{2}\)+N\({}_{2}\) & \(9.6\times 10^{-11}\) & [32; 33; 35; 36] \\ k16 & N\({}_{2}\)+N+N\(\rightarrow\)N\({}_{2}\)(B)+N\({}_{2}\) & \(1.2\times 10^{-33}\) & [35] \\ k17 & N\({}_{2}\)(A)+N\({}_{2}\)(A)\(\rightarrow\)N\({}_{2}\)(B)+N\({}_{2}\) & \(7.0\times 10^{-11}\) & [32; 33] \\ k18 & N\({}_{2}\)(B)\(\rightarrow\)N\({}_{2}\)(A)+hv & \(1.5\times 10^{5}\) & [32; 33; 35; 36] \\ k19 & N\({}_{2}\)(B)+N\({}_{2}\)\(\rightarrow\)N\({}_{2}\)(A)+N\({}_{2}\) & \(5\times 10^{-11}\) & [32; 35; 36] \\ k20 & N\({}_{2}\)(A)+N\({}_{2}\)(A)\(\rightarrow\)N\({}_{2}\)(C)+N\({}_{2}\) & \(3\times 10^{-10}\) & [32; 33; 35; 37] \\ k21 & N\({}_{2}\)(C)\(\rightarrow\)N\({}_{2}\)(B)+hv & \(3\times 10^{7}\) & [32; 33; 35; 36] \\ k22 & N\({}_{2}\)(C)+N\({}_{2}\)\(\rightarrow\)N\({}_{2}\)(a)+N\({}_{2}\) & \(10^{-11}\) & [36] \\ k23 & N\({}_{2}\)(a)+N\({}_{2}\)\(\rightarrow\)N\({}_{2}\)(B)+N\({}_{2}\) & \(2\times 10^{-13}\) & [32; 36] \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Reaction rates considered in this computing model. The species considered in the diluted species transfer equation included N\({}_{2}\)(A), N\({}_{2}\)(B), N\({}_{2}\)(C), N\({}_{2}\)(a), N, O, O\({}_{3}\), NO, NO\({}_{2}\), and NO\({}_{3}\). \[\
abla\cdot\left(-D_{i}^{f}\
abla c_{i}\right)+\mathbf{u}\cdot\
abla c_{i}=R_{i} \tag{9}\]  
Because the concentration (\(c_{i}\)) of these rare species is much lower than that of the surrounding air, the calculation of the diluted species and of N\({}_{2}\), O\({}_{2}\), and N\({}_{2}\)O should be separated to avoid a numerical round-off error.