Abstract: A system operable to allowing viewing of a physical subject with information regarding at least an item separate from the subject overlaid thereon. The system includes a viewscreen. The system is further able to determine the position of the item relative to the subject.

Abstract: Maximum removal of asphaltic material, including high molecular weight metallic contaminants, from a hydrocarbonaceous charge stock is achieved through the utilization of a solvent extraction zone provided with direct heating facilities in an upper portion thereof.

Abstract: Maximum removal of asphaltic material, including high molecular weight metallic contaminants, from a hydrocarbonaceous charge stock is achieved through the utilization of a solvent extraction zone provided with direct top-heating facilities in the upper portion thereof. The top-heating section of the extraction zone is divided into two liquid-collecting zones in partial open communication with each other. A portion of the liquid is removed from the lower liquid-collecting zone, increased in temperature and returned to the extractor in the upper liquid-collecting zone. The flow rate of liquid withdrawn from the lower zone is controlled in response to the differential pressure between the two liquid-collecting zones.