Radial diffusive samplers

Cocheo, V., Boaretto, C. and Sacco, P. (1996) High uptake rate radial diffusive sampler suitable for both solvent and thermal desorption. American Industrial Hygiene Association Journal, 57, 897-904. 

Radiello radial diffusive sampler with activated charcoal... 

Other types of diffusive sampler have been less widely applied for indoor air studies. These include tube type samplers that are solvent desorbed and radial type samplers consisting of a cylindrical adsorbent surface that has a short diffusive path resulting in an effective uptake rate that is typically 100 times that of the tube type sampler (Cocheo, Boaretto and Sacco, 1996). One type of radial sampler developed for measuring carbonyl compounds in indoor air comprises silica gel coated with 2,4-DNPH as the adsorbent within a sintered polyethylene tube that acts as a diffusive membrane (Uchiyamaa, Aoyagi and Ando, 2004). 

Badge-type or radial samplers which have a shorter diffusive path length but a high cross-sectional area. 

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