This paper reports a complete micro gas chromatography(μGC)system in which all the components are lithographically microfabricated and electronically interfaced.The components include a bi-directional Knudsen pump,a ...This paper reports a complete micro gas chromatography(μGC)system in which all the components are lithographically microfabricated and electronically interfaced.The components include a bi-directional Knudsen pump,a preconcentrator,separation columns and a pair of capacitive gas detectors;together,these form the iGC3.c2 system.All the fluidic components of the system are fabricated by a common three-mask lithographic process.The Knudsen pump is a thermomolecular pump that provides air flow to theμGC without any moving parts.The film heaters embedded in the separation columns permit temperature programming.The capacitive detectors provide complementary response patterns,enhancing vapor recognition and resolving coeluting peaks.With the components assembled on printed circuit boards,the system has a footprint of 8×10 cm^(2).Using room air as the carrier gas,the system is used to experimentally demonstrate the analysis of 19 chemicals with concentration levels on the order of parts per million(p.p.m.)and parts per billion(p.p.b.).The tested chemicals include alkanes,aromatic hydrocarbons,aldehydes,halogenated hydrocarbons and terpenes.This set of chemicals represents a variety of common indoor air pollutants,among which benzene,toluene and xylenes(BTX)are of particular interest.展开更多
基金The study was supported in part by the Global Challenges for a Third Century(GCTC)project at University of Michigan.
文摘This paper reports a complete micro gas chromatography(μGC)system in which all the components are lithographically microfabricated and electronically interfaced.The components include a bi-directional Knudsen pump,a preconcentrator,separation columns and a pair of capacitive gas detectors;together,these form the iGC3.c2 system.All the fluidic components of the system are fabricated by a common three-mask lithographic process.The Knudsen pump is a thermomolecular pump that provides air flow to theμGC without any moving parts.The film heaters embedded in the separation columns permit temperature programming.The capacitive detectors provide complementary response patterns,enhancing vapor recognition and resolving coeluting peaks.With the components assembled on printed circuit boards,the system has a footprint of 8×10 cm^(2).Using room air as the carrier gas,the system is used to experimentally demonstrate the analysis of 19 chemicals with concentration levels on the order of parts per million(p.p.m.)and parts per billion(p.p.b.).The tested chemicals include alkanes,aromatic hydrocarbons,aldehydes,halogenated hydrocarbons and terpenes.This set of chemicals represents a variety of common indoor air pollutants,among which benzene,toluene and xylenes(BTX)are of particular interest.
