An orthorhombic phase mixed metal oxide is produced selectively in quantitative yield. At least one cavity is formed adjacent the gate electrode. The results of such decoding are processed to recover successive shortened BCH codewords, some of which are in TRUE form and others of which have had their bits ONEs’ complemented. The inlet channel of the device may also include an adjustable section, or a fixed section and an airflow damper, which allows air flow along the channel to be controlled in a periodic fashion.