Про титан и тантал:
http://jeep.avtograd.ru/cherokee/inj.../89jeepefi.pdf
4.0 LITER MULTI-POINT FUEL INJECTION (1987-1990 RENIX System)
Страница 45 - The resistance element in the O2 sensor is a small
titania semiconductor. The
titania oxygen sensor must be connected into a voltage network..........................
..........................
The heater is needed to maintain the
titania semiconductor at its operational temperature of approximately 1475 degrees (850 degrees C)