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Increasing public concern regarding air quality has led to the development of efficient aerosol-monitoring techniques. Among the various aerosol measurement instruments based on electrical methods, in this study, an electrical cascade impactor (ECI) was designed and fabricated in our laboratory and was used to measure the real-time size distributio...
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... reasons for the lower DLPI effectiveness are as follows: i) Any diluter was applied ahead of the DLPI; thus, it was impossible to cover the entire combustion period using one DLPI (column DLPI coverage, Table S4). The two available impactors were used sequentially during the combustion tests with a time delay due to their cleaning, reassembly and pre-heating. The average values measured in the adjacent collections were used to calculate the EFs. The number of used DLPIs is mentioned in Table S4. It is recommended to increase the dilution ratio to cover the entire period of sampling by the DLPI to avoid filling the DLPI or use a diluter ahead of the DLPI. ii) A decrease of pressure below the 8 th stage in the DLPI (< 0.4 bar) could cause desorption of PAHs, especially from the PM 1 fraction, and hence lower the EF Σ 4 PAHs in PM 10 that were measured via the DLPI ( Hays et al., 2003). A solution could be the use of less stages in the DLPI so the pressure would not be that low and the pressure would be comparable with the pressure in the dilution tunnel. The effectiveness of the DLPI and cyclone should be compared by including the rinsing of the DLPI, especially in the case of lighter PAHs; however, the DLPI was rinsed only in tests no. 3 and 4 (not included in Fig. 4). The highest EFs of 4 PAHs were observed in the old- type boiler (B3) by comparison of the same fuel and the same conditions of combustion, see Table S4 and Fig. 4. It was confirmed that the efficient combustion at P nom generated lower emissions of 4 PAHs and PM (for all fractions) as compared for B1, B4 and B5 boilers which was reported as well in other studies (Kubica, 2007;Ravindra, ...
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... reasons for the lower DLPI effectiveness are as follows: i) Any diluter was applied ahead of the DLPI; thus, it was impossible to cover the entire combustion period using one DLPI (column DLPI coverage, Table S4). The two available impactors were used sequentially during the combustion tests with a time delay due to their cleaning, reassembly and pre-heating. The average values measured in the adjacent collections were used to calculate the EFs. The number of used DLPIs is mentioned in Table S4. It is recommended to increase the dilution ratio to cover the entire period of sampling by the DLPI to avoid filling the DLPI or use a diluter ahead of the DLPI. ii) A decrease of pressure below the 8 th stage in the DLPI (< 0.4 bar) could cause desorption of PAHs, especially from the PM 1 fraction, and hence lower the EF Σ 4 PAHs in PM 10 that were measured via the DLPI ( Hays et al., 2003). A solution could be the use of less stages in the DLPI so the pressure would not be that low and the pressure would be comparable with the pressure in the dilution tunnel. The effectiveness of the DLPI and cyclone should be compared by including the rinsing of the DLPI, especially in the case of lighter PAHs; however, the DLPI was rinsed only in tests no. 3 and 4 (not included in Fig. 4). The highest EFs of 4 PAHs were observed in the old- type boiler (B3) by comparison of the same fuel and the same conditions of combustion, see Table S4 and Fig. 4. It was confirmed that the efficient combustion at P nom generated lower emissions of 4 PAHs and PM (for all fractions) as compared for B1, B4 and B5 boilers which was reported as well in other studies (Kubica, 2007;Ravindra, ...
Context 3
... stages in the DLPI so the pressure would not be that low and the pressure would be comparable with the pressure in the dilution tunnel. The effectiveness of the DLPI and cyclone should be compared by including the rinsing of the DLPI, especially in the case of lighter PAHs; however, the DLPI was rinsed only in tests no. 3 and 4 (not included in Fig. 4). The highest EFs of 4 PAHs were observed in the oldtype boiler (B3) by comparison of the same fuel and the same conditions of combustion, see Table S4 and Fig. 4. It was confirmed that the efficient combustion at P nom generated lower emissions of 4 PAHs and PM (for all fractions) as compared for B1, B4 and B5 boilers which was ...
Context 4
... DLPI and cyclone should be compared by including the rinsing of the DLPI, especially in the case of lighter PAHs; however, the DLPI was rinsed only in tests no. 3 and 4 (not included in Fig. 4). The highest EFs of 4 PAHs were observed in the oldtype boiler (B3) by comparison of the same fuel and the same conditions of combustion, see Table S4 and Fig. 4. It was confirmed that the efficient combustion at P nom generated lower emissions of 4 PAHs and PM (for all fractions) as compared for B1, B4 and B5 boilers which was reported as well in other studies (Kubica, 2007;Ravindra, ...
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The particle size distribution of urban aerosols is typically dominated by ultrafine particles (UFP) originating from local sources such as traffic and industrial emissions. Due to their negligible mass they are clearly underrepresented by legislative PM10 mass measurements. This is one reason why their contribution to urban air quality is better c...
Citations
... The electrical low-pressure cascade impactor was developed further for achieving higher resolution with 100 or 500 size fractions (i.e. HR-ELPI+) (Saari S. et al., 2018) or measuring nanoparticle mass concentration using a wire-to-rode corona charger to eliminate the new particle formation which may occur in the pin-to-plate corona charger (Han J. et al., 2018). ...
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