Automated Gas Sampling System for Laboratory Analysis of CH4 and N2O.

Analyzing the flux of CH[SUB4] and N[SUB2]O from soil is labor intensive when conventional hand injection techniques are utilized in gas chromatography. An automated gas sampling system was designed and assembled from a prototype developed at the National Soil Tilth Laboratory in Ames, IA. The sampler was evaluated for accuracy and precision when attached to a Varian[SUB-1] 3700 gas chromatograph configured with flame ionization and electron capture detectors. The automated gas sampling system is easy to operate and provides acceptable results (standards ranging from 1.0-5.0ppmv CH[SUB4] and 0.342-2.0ppmv N[SUB2]O had coefficients of variation ranging from 1.7-5.6%) while providing an economical approach for analyzing large numbers of gas samples with minimal labor and equipment cost. [ABSTRACT FROM AUTHOR]