Example An Oxygen Sensor

Platinum and palladium porphyrins in silicon rubber resins are typical oxygen sensors and carriers, respectively. An analysis of the characteristics of these types of polymer films to sense oxygen is given in Ref. 34. For the sake of simplicity the luminescence decay of most phosphorescence sensors may be fitted to a double exponential function. The first component gives the excited state lifetime of the sensor phosphorescence while the second component, with a zero lifetime, yields the excitation backscatter seen by the detector. The excitation backscatter is usually about three orders of magnitude more intense in small optical fibers (100 than the sensor luminescence. The use of interference filters reduce the excitation substantially but does not eliminate it. The sine and cosine Fourier transforms of/(f) yield the following results  

Other applications of the instrumentation and techniques here presented may include (i) temperature sensing employing alexandrite, ruby crystals, and Nd YAG crystals.(35 41) pH and partial pressure of carbon dioxide (pCCh) may be determined employing carboxy seminaphtorhodafluor (SNARF)-6.(42) 

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