Current Status off Prominent Selective Gas Chromatographic Detectors: A Critical Assessment

Waste tank ventilation rates measured with a tracer gas method

“…Three calibration ranges were needed to minimize the . effects of the nonlinear response of the ECD to this strongly electron-capturing compound (Farwell et al 1981). The three,calibration curves ranged from 0.030 to 1.0 ppbv (linear regression based on 3 points), 1 to 20 ppbv (quadratic fit based on 4 points), and 20 to 160 ppbv (cubic fit based on 5 points).…”

Applications of Supercritical Fluids in Industrial Analysis

“…The alkali metal stimulates the formation of ions from electronegative species, particularly nitrogen and phosphorus, compared to carbon compounds (Farwell et al, 1981). The first study with SFC in carbon dioxide and in nitrous oxide was performed by Fjeldsted et al (1983a).…”

Instrumental Aspects of Gas Chromatography

“…The structure-selective, electron-capture detector (ECD) is the second most widely used ionization detector [115][116][117][118]. It owes much of its popularity to its unsurpassed sensitivity to a wide range of toxic and biologically active compounds.…”

“…The most widely used element-selective electrochemical detector is the Hall electrolytic conductivity detector (HECD) [98,116,206]. This is an improved version of an earlier design by…”

“…The liquid phase is separated from insoluble gases in a gas-liquid separator and then passed through a conductivity cell. Hall also improved the method of measuring sample conductance by employing an AC conductivity bridge in earlier designs and, more recently, a bipolar, pulsed, differential conductance circuit and cell design [116,210,211]. The HECD employs a small-volume, concentric cylinder cell for mixing, separating, and monitoring the concentration of conducting species, Figure 3.16.…”