LASER TWO-PHOTON IONIZATION FOR TRACE DETECTION OF BTEX IN AMBIENT AIR

摘要

The following conclusions can be drawn from the data of Figure 2, Figure 3, and Figure. 4. The total amount of BTEX can be obtained sensitively only if its signal current is detected by laser two-photon ionization technique. Experimental results showed that the method not only can realize high speed and real time but also high sensitivity detection. The detection limits of BTEX are on the order of 10 ppb. As regards sensitivity, the experiments also indicated that the collection efficiency of the electrodes could be increased providing adequate electrode area and voltage, and the repetition rate of UV laser was raised. Hence, this method is a very sensitive technique for detection of BTEX in ambient air.