Oxygen. Paramagnetic, Zirconia, Tunable Diode Lasers
Oxygen is vitally important to the existence of animal life, not only for respiration, but also for the many aspects of the combustion reaction (power generation, vehicular movement, heating) and process control, safety and quality. Continuous measurement techniques are correspondingly important and very specialized. The ability of zirconium oxide to conduct oxygen ions at high temperatures has enabled specific measurement in situ in combustion processes. Less studied and understood have been the older established paramagnetic properties of oxygen and the more recent near infrared absorption enabling measurement via tunable diode lasers. These analytical methods are both related to the unusual electronic structure of the oxygen molecule.
Lavoisier, a chemical revolutionary, bequeathed the name Oxygen and finally established that oxygen was the reactive component of air (Ref. 1). He famously demonstrated the combustion reaction by vaporizing the Holy Emperor's diamonds, forming carbon dioxide, in an early example of the worlds most useful, although now increasingly worrying, chemical reaction.
The exothermic reaction of oxygen with hydrocarbons drives the planet's land, sea and air-based vehicles and provides heat and power for industrial and domestic use.
On Line Measurement of Oxygen: Review and New Developments