Abstract: A method and a device for measuring nitrogen oxides in a gas stream. A functional layer in the sensor senses nitrogen oxides and a measurable physical variable of the functional layer changes in direct correlation with the concentration of nitrogen oxide molecules in the gas. The functional layer is made of a material that, when heated to a specific operating temperature and held at that temperature, maintains an equilibrium between storage and desorption of the nitrogen oxide molecules, and this eliminates the need for a regeneration phase, as is the case with a dosimeter. At the specified operating temperature, the gas sensor indicates a direct relationship between the measured variable and the concentration of the surrounding gas.

Abstract: The invention relates to an arrangement for fill-level measurement of an electrically conductive liquid in a container, in particular for fill-level measurement in a reducing agent tank of an exhaust gas aftertreatment system, whereby a large number of electrodes (3, 4) are arranged some distance apart above one another in the vertical direction (2), so that the filling level can be derived from a change in the electrical potential difference between the two electrodes (3, 4) that results from the bridging of the distance between two electrodes (3, 4) with a conductive liquid, whereby the electrodes (3, 4) are connected to terminals by strip conductors (7, 8), whereby the electrodes (3, 4) and the strip conductors (7, 8) are embedded in a flexible carrier medium (1), and the strip conductors (7, 8) are elastic and crushable.