\begin{table}%t1
%\centering
\par
\caption{\label{journal}Journal of observations.} 
\begin{tabular}{l c c c l c c c}
\hline \hline
Quasar  & $V$     & $z_{\rm em}$ & $z_{\rm abs}$ & Observing date & Mode & Wavelength range & Exposure time \\
        & [mag] &              &               &                &      & [nm]             & [s]     
\\    \hline  
Q0100+13   & 16.6 & 2.69 & 2.309 & September 2001 & dic2 (390+860) & 330$-$452/670$-$1000 & 7200 \\
Q1331+17   & 16.7 & 2.08 & 1.776 & June--July 2001 & dic1 (346+860) & 312$-$387/670$-$1000 & 13~500 \\
Q2231$-$00 & 17.5 & 3.02 & 2.066 & September 2000 & dic2 (390+800) & 335$-$452/610$-$990  & 15~700 \\
Q2343+12   & 17.0 & 2.55 & 2.431 & August 2001    & dic1 (346+860) & 315$-$387/670$-$1000 & 14~400 \\
\hline
\end{tabular}
\end{table}