\begin{table}%t6
\caption{Aliphatic column density ($N[3.4] = N{\rm [CH}_{2}] + N{\rm [CH}_{3}$], see
Table~\ref{aliphatic}) in the region
2800$-$3000~cm$^{-1}$ and silicate column density ($N$[10]) around 1000~cm$^{-1}$)
of  the IDPs after the HF treatment, calculated after a baseline correction.  See text for error estimates.\label{SiO-postHF}}
%%\centerline
\par
{
    	\begin{tabular}{cccccc}
        \hline	\hline
        IDP & area [3.4]  & area [10] &  $N$[3.4]  & $N$[10]  &  SiO remaining  \\
	&  & & (aliph C atom/cm$^{2}$)  & (Si atoms/cm$^{2}$) & $\%$  \\
        \hline
W7116B-N  & 0.20 & 0.9 & $2.6 \times 10^{16}$ & $1.1 \times 10^{16}$ & 40 \\
W7116B-Y  & 0.33 & 5.1 & $4.2 \times 10^{16}$ & $5.9 \times 10^{16}$ & 98  \\
W7116B-U  & 0.15 & 2.6 & $2.3 \times 10^{16}$ & $3.1 \times 10^{16}$ & 26  \\
L2036-E19 & 0.02 & 0.3 & $^{*}2.0 \times 10^{15}$ & $3.7 \times 10^{15}$ & 6 \\
L2021-K3  & 0.12 & 0.1 & $1.4 \times 10^{16}$ & $1.3 \times 10^{15}$ & 3  \\
L2021-K2  & 0.17 & 0.9 & $1.9 \times 10^{16}$ & $1.1 \times 10^{16}$ & 30  \\
L2011-F2  & 0.09 & 0.1 & $1.3 \times 10^{16}$ & $1.6 \times 10^{15}$ & 2   \\
        \hline
\end{tabular}}
\medskip
$^{*}$ This value was obtained by integration of the
whole 3.4~$\mu$m feature, since the CH$_{2}$ and CH$_{3}$ peaks were not well resolved.
	\end{table}