The invention relates to a holding device provided with a receiving system for receiving a mobile telephone, said holding device comprising a housing. A developer carrier conveys a one-component non-magnetic developer and develops the latent image either in close proximity to or in contact with the latent image carrier. The rotationally-asymmetrical aspherical surface has a first rotationally-asymmetrical component to add said cylindrical power for correcting astigmatism of an eye and a second rotationally-asymmetrical component to correct the aberrations in the directions between first and second principal meridians caused by adding the cylindrical power. 0 parts by mass of a mercaptobenzimidazole compound. Furthermore, there are described different embodiments and devices for these elements. A combustion boiler and a generator engine, driven with synthesis gas, are associated with a single gasifier, and the gasifying apparatus produces synthesis gas proper to a technical field of the gasifier by selectively applying an upflow gasifier and a downflow gasifier according to the technical field of the gasifier.