Abstract: A control unit for a motor vehicle, having a supply connection for receiving a supply voltage from a supply line needing to be secured against a reaction from the control unit, wherein to protect against the reaction there is provision in a current path of the supply connection for a unidirectional first blocking element, and a diagnostic circuit is configured to check the blocking effect thereof by a predetermined diagnostic routine. An additional, second unidirectional blocking element is connected in series with the blocking element in the current path of the supply connection, wherein the first and the second blocking element each provide for a unidirectional flow of current to the device circuit, and the diagnostic circuit is configured to use the diagnostic routine to also check the blocking effect of the second blocking element.

Abstract: A solid-state nuclear magnetic resonance (NMR) method for investigating a sample material, which contains protons H and also spin-1/2 hetero nuclei X, uses a sample material rotated at the magic angle. The method comprises the steps of increasing the equilibrium polarization of X; eliminating (2) proton magnetization; transferring polarization from X to H; and recording the proton signals (8) under a condition of line narrowing. A radio frequency (RF) pulse sequence effects polarization transfer between X and the closest protons H, via dipole coupling with coupling constant DXH. A parameter, which is associated with the transfer process, is varied to determine the dipole coupling constant DXH and thereby permits precise determination of the binding separation X—H, even when the concentration of X is small compared to H.

Abstract: A solid-state nuclear magnetic resonance (NMR) method for investigating a sample material, which contains protons H and also spin-1/2 hetero nuclei X, uses a sample material rotated at the magic angle. The method comprises the steps of increasing the equilibrium polarization of X; eliminating (2) proton magnetization; transferring polarization from X to H; and recording the proton signals (8) under a condition of line narrowing. A radio frequency (RF) pulse sequence effects polarization transfer between X and the closest protons H, via dipole coupling with coupling constant DXH. A parameter, which is associated with the transfer process, is varied to determine the dipole coupling constant DXH and thereby permits precise determination of the binding separation X-H, even when the concentration of X is small compared to H.