||Development of Improved Systems for Obtaining Time Integrated Measurements of SO2, NO2, NOx, and Other Pollutants.
Huebne, Victor R. ;
||Instra-Tech, Inc., Fullerton, Calif.
Air pollution ;
Sulfur dioxide ;
Nitrogen oxides ;
Chemical reactions ;
Digital recording ;
Chemical analysis ;
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
The aims were to develop methods of detecting light emitted by chemiluminescence which are more stable and reliable than those presently used and to develop a simplified method of time-integrating and recording the outputs of chemiluminescence instruments. Primary effort was placed on elimination of the photomultiplier tube system by using photographic film as the detector as well as recorder. When this approach proved to be unsuccessful, digital photon counting methods were explored. This approach was quite successful. A system was developed that amplified each photoelectron, discriminated against noise pulses, accumulated all the photon counts, and displayed the sum of the photon counts on a 5 x 7 light emitting diode display.