A flame spray pyrolysis process for the preparation of ultrafine titania particles coated with a smooth, homogeneous coating of one or more metal oxides is provided. The system includes an indexer that stores a plurality of reticles and a removable reticle cassette. The impingement sleeve has a plurality of openings where a portion of the openings each have a feed tube extending through the opening and into the passageway. The compensation voltage is applied to the DC output voltage to thereby regulate the voltage level of the DC output voltage.