Prediction of Uptake Rates for Diffusive Tubes

28 Jul 2015

This Application Note describes the theory and practice of predicting the uptake rate for a particular analyte–sorbent combination when using diffusive (passive) samplers. This can help analysts to overcome the limitation of having to experimentally determine uptake rates for every analyte–sorbent combination of interest.

Sorbent sampling tubes

Markes International Ltd

Thermal desorption sorbent sampling tubes for air sampling. Backed up by fast and friendly service, Markes’ tubes provide optimum sampling and analytical performance. Our range includes everything from cost-effective packages of industry-standard tubes to the last word in sorbent tube innovation. Features: Our industry-standard (3½-inch (89 mm) long x ¼-inch (6.4 mm) o.d.) sorbent tubes are available in stainless steel, inert-coated stainless steel and glass. Compatible with thermal desorption instruments manufactured by Markes International, PerkinElmer and Shimadzu. All tubes are permanently labelled with a unique serial number, barcode and sampling flow arrow, so that they are easy to use and track. Further labelling options for tube tracking – includes laser-etching, banding and RFID-tagging (TubeTAG™). Diffusion-locking SafeLok™ options for additional peace of mind. Stringent quality control – our tubes are packed to a tolerance of ±2.5% or better. Application-specific sorbent tubes – optimally packed for applications ranging from air toxics to material emssions testing. Our sorbent tubes can also be ordered conditioned and capped, so that they’re ready for use on arrival. All our sorbent tubes can be supplied: empty for you to pack yourself (or for direct desorption); pre-packed with one sorbent bed for diffusive (passive) monitoring applications; or pre-packed with up to three sorbent beds for pumped (active) monitoring applications. We also supply 4½-inch DAAMS tubes (regular and high-flow, in any of the above materials) – contact us for details.

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