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PubMed · 12541851

[Dynamic pre-concentration method of gas sample].

H Miao·Y F Guan·H W Wang·D Q Zhu
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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.

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AbsorptionAlkanesAttentionChromatography, GasEthaneEthylenesSpecimen HandlingTemperatureEnglish AbstractJournal Article

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H Miao, Y F Guan, H W Wang, D Q Zhu. 2001. [Dynamic pre-concentration method of gas sample].. https://pubmed.ncbi.nlm.nih.gov/12541851/

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