Figures & data
FIG. 1 Experimental setup used for studying the filter artifact. Depending on the aerosol composition, DMM, SMPS, and/or gas analyzer are connected to the system. Letter c denotes the common port of the three-way valves. MFC, mass flow controller.
TABLE 1 Summary of the performed experiments showing soot and hydrocarbon (HC) concentrations, initial filter soot load (expressed as the percentage of clean filter mass), sampling time, and associated figures presenting the results
FIG. 2 Effect of sampling time on filter artifact for initially clean filters (open squares) and sooty filters with 0.13% soot content (filled squares). Arrows indicate filter artifact for pentadecane concentrations other than 12 ppm. Error bars indicate the estimated uncertainty of measurement results.
FIG. 3 Filter artifact for an initially clean filter and for filters with different soot loads (expressed as the percentage of clean filter mass). The pentadecane concentration was 12 ppm during the 20-min measurement. Photographs of the filters are shown in the subfigure. Error bars indicate the estimated uncertainty of measurement results. (Color figure available online.)
FIG. 4 Filter mass gain when sampling only soot (white columns) and a mixture of soot and pentadecane (dotted columns and artifact corrected result as checkered columns). The soot concentrations were kept constant at 130 μg/m3 (low soot content) and 700 μg/m3 (high soot content) and the pentadecane concentration was 10 ppm during the 20-min measurement. Error bars indicate the estimated uncertainty of measurement results.
