A centrifuge container transport rack designed with symmetrical opposing sides located over a central pivot. The exhaust system may have a passageway connected to receive an exhaust flow from the combustion source, and a sensor disposed within the passageway. The system is arranged so that when the reflection detecting means detect that the light beam is reflected by an element, the corresponding position of incidence of the light on the detector is taken as an indication of the displacement of the element. Each array produces respective electrical signals that are characteristic of magnetic transitions recorded on a magnetic recording medium. The modified yttrium hydroxycarbonate may have a pore size distribution with a pore diameter peak of less than or equal to 10 nm. Methods and apparatus are provided which use pre-set digital gains or digital gain adjustments to compensate for the non-linearities as a function of total transmit power such that at the output, the desired relative powers are observed.