A method for booting up a mobile phone quickly is disclosed. The hood is hinged adjacent one end for upward pivoting between a closed position in which an associated engine is covered and an open position which provides access to the engine. The aryl group can be a five- or six-membered heterocyclic ring. The method and apparatus may also include an x-ray detector having a small-area, for example, a PIN-diode type semiconductor x-ray detector, that can provide effective x-ray detection at room temperature.