\section{Das Verhalten der Feldgrössen an Grenzflächen}

\begin{minipage}{0.6\linewidth}
  \includegraphics[width=\textwidth]{fig/Fig39.png}
\end{minipage}
\begin{minipage}{0.4\linewidth}

  \[
  J_{n_1} = J_{n_2}
  \]

  \[
  \frac{E_{n_1}}{E_{n_2}} = \frac{\kappa_2}{\kappa_1}
  \]  

  \[
  E_{t_1} = E_{t_2}
  \]
  
  \[
  \frac{J_{t_1}}{J_{t_2}} = \frac{\kappa_1}{\kappa_2}
  \]
  
\end{minipage}