The detection of a mixture of nine explosive compounds, including nitrate esters, nitroaromatics, and a nitramine in less than 140 sec is described. The new method employs a commercially available pulsed-discharge electron capture detector (PDECD) coupled with a microbore capillary gas chromatography (GC) column in a standard GC oven to achieve on-column detection limits between 5 and 72 fg for...

An abscisic acid derivative was formed by reaction with pentafluorobenzyl bromide which allowed highly sensitive detection by gas-liquid chromatography with electron capture detection. In comparison to the methyl ester derivative, the pentafluorobenzyl derivative of abscisic acid was four times more sensitive to electron capture detection and was stable at room temperature in the presence of ul...

Chlorine has been widely used to kill disease-causing microbes in drinking water. During the disinfection process, organic and inorganic material in source waters can combine with chlorine and certain other chemical disinfectants to form disinfection by-products. The kind of disinfectant used can produce different types and levels of disinfectant byproducts in the drinking water, such as trihal...

A reliable and simple procedure to extract polychlorinated biphenyls (PCBs) from marine mussels using microwave energy is proposed. Freeze-dried mussels were subjected to MASE (Microwave Assisted Solvent Extraction) in a closed-vessel microwave system with n-pentane-sodium hydroxide (5 %) or dichloromethane-pentane (1:1) at different temperatures (70 and 90 oC), the extraction time was 10 minut...

Gas chromatography–mass spectrometry and gas chromatography with electron-capture detection have been investigated for analysis of persistent chlorinated aromatic compounds in the aquatic environment. A range of polychlorinated veratroles, guaiacols, and catechols produced during pulp bleaching and during PCB degradation were derivatized with pentafluorobenzyl bromide to improve their chromatog...

The electron capture gas liquid chromatography test method for chick edema factor has been modified by replacing the alumina column s t ep with an additional sulfuric acid cleanup and a caustic wash which permits a reduction in sample cleanup time. Samples are subjected to double preliminary sulfuric acid cleanup and caustic wash and extracted each time with t r imethyl pentane. The final extra...