From Kin-Tek Laboratories Inc.
Teflon® permeation tubes are a proven method for making trace concentration gas mixtures when used in their equilibrium state. Permeation rates are established by a gravimetric weight loss method after equilibration at a stable temperature. Frequently, permeation tubes are subjected to drastic temperature changes when stored at low temperatures or used over a range of temperatures. Such changes can cause transient characteristics that result in substantial deviation from expected permeation rate data. Performing calibrations during non-equilibrated transient phases affect analyses and wastes time. This paper investigates transient temperature characteristics and establishes equilibrium times for disposable type permeation tubes containing hydrogen sulfide (H2S), carbonyl sulfide (COS), toluene (C6H5CH3), and water (H2O).
Topics of Interest
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S.IPSALE FINE Permeation Tubes, Messina, ITALY N.DONATO Dept. of Matter Physics and Advanced Technologies and INFM, University of Messina, ITALY G. NERI, A.BONAVITA, G.RIZZO, S.GALVAGNO...
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