Abstract
A simple Instrumental setup for quantitative chemical analysis, based on the measurement of the time-resolved voltage Induced on electrodes by MPI-generated charges, Is suggested and evaluated. The method Is suitable for on-line measurements and may achieve detectability close to the ppb range for highly efficient Ionization (either by resonant MPI or by use of ps-lasers) and up to two parts In 107(for nonresonant two-photon Ionization by ns-lasers). The dynamical range of the detectable concentrations Is considerably larger compared to other related techniques. With a KrF exclmer laser used for Ionization, the Instrument can be used as an artificial nose for sensing organic compounds In atmospheric air. The method performs best In the determination of the mass and number of Ions In a monocomponent system; however, simple binary mixtures can be resolved as well. The measurements reported here are carried out at pressures up to 10-3mbar, using an unfocused laser beam. The “heart” of the method Is a chemometrlc set of algorithms that extracts the Information on the masses and number of Ions out of the easily obtained signal.
Original language | English |
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Pages (from-to) | 2787-2796 |
Number of pages | 10 |
Journal | Analytical Chemistry |
Volume | 64 |
Issue number | 22 |
DOIs | |
State | Published - Nov 1992 |
Externally published | Yes |