title: [Dynamic pre-concentration method of gas sample].
abstract: By utilizing the combination of frontal chromatography at ambient temperature, back-flushing and temperature gradient thermal desorption, a prototype of a dynamic pre-concentration system has been designed and evaluated. It realized the enrichment for gas samples of boiling point higher than - 103 degrees C without cryogenic facilities. To reduce the sample volume and enhance enrichment factor, the technique of momentarily non-steady state produced at the beginning of back-flushing, and the negative temperature gradient generated during thermal desorption were utilized, resulting a very sharp desorption band. Standard samples were tested to demonstrate the applicability of the method. At 10 mL sample volume, the enrichment factor was 100.
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116012, China.
authors.forename: H
authors.initials: H
authors.lastname: Miao
authors.forename: Y F
authors.initials: YF
authors.lastname: Guan
authors.forename: H W
authors.initials: HW
authors.lastname: Wang
authors.forename: D Q
authors.initials: DQ
authors.lastname: Zhu
mesh_terms: D000042:Absorption; D000473:Alkanes; D001288:Attention; D002849:Chromatography, Gas / Q000295:instrumentation / Q000379:methods*; D004980:Ethane / Q000032:analysis / Q000737:chemistry; D005030:Ethylenes / Q000032:analysis* / Q000737:chemistry; D013048:Specimen Handling / Q000379:methods*; D013696:Temperature
chemical_list: D000473:Alkanes; D005030:Ethylenes; C036216:ethylene; D004980:Ethane