\frac{dx_{1}}{dt} = -1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{1} / k_{31}\\
\frac{dx_{2}}{dt} = \left(-1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{2} + 1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{1}\right) / k_{31}\\
\frac{dx_{3}}{dt} = \left(1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{2} + -1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{3}\right) / k_{31}\\
\frac{dx_{4}}{dt} = \left(1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{3} + -1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{4}\right) / k_{31}\\
\frac{dx_{5}}{dt} = \left(1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{4} + -1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{5}\right) / k_{31}\\
\frac{dx_{6}}{dt} = \left(1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{5} + -1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{6}\right) / k_{31}\\
\frac{dx_{7}}{dt} = \left(1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{6} + -1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{7}\right) / k_{31}\\
\frac{dx_{8}}{dt} = \left(1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{7} + -1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{8}\right) / k_{31}\\
\frac{dx_{9}}{dt} = 1 \cdot k_{31} \cdot k_{29} \cdot \exp\left(k_{30} \cdot t\right) \cdot x_{8} / k_{31}