Urban background, PNCs

Fig. 2 Typical contribution of various sources towards (a) roadside PNCs in the 14.9-10,000 nm size range London, and (b) urban background PNCs in the 13-800 nm size range in Barcelona. Roadside and urban background data has been taken from Harrison et al. [19] and Pey et al. [18], respectively...

Fig. 4 Typical urban background average PNCs in different European cities. Data has been taken from the references listed in Table 1...

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