A novel process is provided for the preparation of 4-aryl piperidines, and the useful intermediates obtained therein. The device has a bladder located in the interior of the belt layer that provides structural support for the belt layer and surface layer and a hub that is in contact with the surface layer and is connected to an axle. The method includes providing a continuous actuation button configured to initiate the communication link. Subsequently, when the noise level reaches Level 2, the CPU is suspended. However, time release pellets could also be used. The determination unit determines the charge build-up state of the substrate based on a change in the current value, the change being accompanied by a change in the scan position.