\begin{table} \caption{\label{Table:Ratios}Physical parameters and abundances.} \small%\centerline { \begin{tabular}{lccccccc} \hline\hline Parameter & knot~1 & knot~2 & knot~3 & knot~4 & knot~5 & Nucleus & Integrated \\ \hline &&&&&&& \\[-8pt] $\log\left(\frac{\left[\mbox{\ion{O}{iii}}\right]\;\lambda5007}{\Hb}\right)$ & $ 0.56\pm0.02$ & $ 0.54\pm0.02$ & $ 0.50\pm0.03$ & $ 0.25\pm0.03$ & $ 0.52\pm0.04$ & $ 0.37\pm0.05$ & $ 0.50\pm0.02$ \\[2pt] $\log\left(\frac{\left[\mbox{\ion{N}{ii}}\right]\;\lambda6584}{\Ha}\right)$ & $-1.04\pm0.02$ & $-1.00\pm0.02$ & $-1.12\pm0.05$ & $-0.97\pm0.05$ & $-1.18\pm0.09$ & $-0.94\pm0.08$ & $-1.03\pm0.02$ \\[2pt] $\log\left(\frac{\left[\mbox{\ion{S}{ii}}\right]\;\lambda\lambda6717,\;6731}{\Ha}\right)$ & $-0.79\pm0.02$ & $-0.73\pm0.02$ & $-0.75\pm0.03$ & $-0.59\pm0.04$ & $-0.77\pm0.07$ & $-0.46\pm0.06$ & $-0.61\pm0.02$ \\ &&&&&&& \\[-8pt] \hline &&&&&&& \\[-8pt] $N_{\rm e}$([\ion{S}{ii}]) (cm$^{-3}$) & 190 & ${\leq}100$ & ${\leq}100$ & 108 & ${\leq}100$ & ${\leq}100$ & ${\leq}100$ \\ $T_{\rm e}$([\ion{O}{ii}]) (10$^{4}$ K) & $1.18\pm0.07$ & $1.22\pm0.07$ & --- & --- & --- & --- & $1.67\pm0.30$ \\ $T_{\rm e}$([\ion{O}{iii}]) ($10^{4}$ K) & $1.27\pm0.10 $ & $1.33\pm0.10 $ & --- & --- & --- & --- & $1.96\pm0.42$ \\ $12+\log(O/H)$ -- ($T_{\rm e}$) & $8.09\pm0.06 $ & $8.03\pm0.06 $ & --- & --- & --- & --- & $7.71\pm0.13$ \\ $12+\log(\rm {O/H})$ -- ($N2$) & 8.26 & 8.28 & 8.23 & 8.30 & 8.20 & 8.31 & 8.27 \\ $12+\log({\rm O/H})$ -- ($O3N2$) & 8.22 & 8.24 & 8.21 & 8.34 & 8.19 & 8.31 & 8.24 \\ $12+\log({\rm S}^{+}/{\rm H}^{+})$ & $5.87\pm0.05$ & $5.90\pm0.05$ & --- & --- & --- & --- & $5.80\pm0.10$ \\ $12+\log({\rm N}^+/{\rm H}^+)$ & $6.52\pm0.05$ & $6.59\pm0.05$ & --- & --- & --- & --- & $6.26\pm0.11$ \\ $\log({\rm N/O})$ & $-1.29\pm0.10$ & $-1.18\pm0.10$ & --- & --- & --- & --- & $-1.27\pm0.21$ \\ \hline \end{tabular}} \medskip Notes: $T_{\rm e}$ ([\ion{O}{ii}]) derived from the relation: $T_{\rm e} {\rm ([\mbox{\ion{O}{ii}}])}=0.72$~$\times$ $T_{\rm e} {\rm ([\mbox{\ion{O}{iii}}])} + 0.26$ found by \cite{Pilyugin2006}; $T_{\rm e}$ ([\ion{O}{iii}]): electron temperature measured from [\ion{O}{iii}]~$\lambda4363$; $12+\log({\rm O/H})$~-- ($T_{\rm e}$): direct O/H~abundance derived from $T_{\rm e}$[\ion{O}{iii}]; $12+\log({\rm O/H})$~-- ($N2$): O/H derived from the $N2$~index \citep{PettinPagel2004}; the associated uncertainty is ${\pm}0.38$; $12+\log({\rm O/H})$~-- ($O3N2$): O/H derived from the $O3N2$~index \citep{PettinPagel2004}; the associated uncertainty is $\pm0.25$. \end{table}