Collection efficiency annular denuders

The efficiency of HN03 collection with a single annular denuder should be confirmed by each user with a known source of HN03, regardless of denuder coating used. On the basis of laboratory studies, Ferm and Sjodin (42) reported a technique that can be used to correct simultaneously for penetration of HN03 through the first of tandem denuders as well as for artifact N03" due to atmospheric species retained with low efficiency. 

Figure 1. Collection efficiency (f)for a denuder of annular geometry in which only the inner surface of the annulus is a sink as a function of axial position X (see equation 14). The curves are based on numerical data in reference 54. From top to bottom, the traces correspond to dj/d0 = 1.0, 0.5, 0.25, 0.1, 0.05,...

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