Diurnal and seasonal cycles of ozone precursors observed from continuous measurement at an urban site in Taiwan

Yang, Kai; Ting, Chien Chung; Wang, Jia Lin; Wingenter, O. W.; Chan, Chang-Chuan

doi:10.1016/j.atmosenv.2005.02.003

Cited by 59 publications

(20 citation statements)

References 29 publications

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“…A closer look at isoprene's diurnal pattern reveals a sharp contrast to tailpipe compounds, such as ethylene and CO (See Supporting Information). In this illustration, isoprene shows a clear midday maximum because its production is largely solar radiation and temperature driven, as has been demonstrated by numerous previous studies .…”

Section: Resultssupporting

confidence: 71%

Construction of a cryogen-free thermal desorption gas chromatographic system with off-the-shelf components for monitoring ambient volatile organic compounds

et al. 2016

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An automated gas chromatographic system aimed at performing unattended measurements of ambient volatile organic compounds was configured and tested. By exploiting various off-the-shelf components, the thermal desorption unit was easily assembled and can be connected with any existing commercial gas chromatograph in the laboratory to minimize cost. The performance of the complete thermal desorption gas chromatographic system was assessed by analyzing a standard mixture containing 56 target nonmethane hydrocarbons from C2 -C12 at sub-ppb levels. Particular attention was given to the enrichment efficiency of the C2 compounds, such as ethane (b.p. = -88.6°C) and ethylene (b.p. = -104.2°C), due to their extremely high volatilities. Quality assurance was performed in terms of the linearity, precision and limits of detection of the target compounds. To further validate the system, field measurements of target compounds in ambient air were compared with those of a commercial total hydrocarbon analyzer and a carbon monoxide analyzer. Highly coherent results from the three instruments were observed during a two-month period of synchronized measurements. Moreover, the phenomenon of opposite diurnal variations between the biogenic isoprene and anthropogenic species was exploited to help support the field applicability of the thermal desorption gas chromatographic method.

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Section: Resultssupporting

confidence: 71%

Construction of a cryogen-free thermal desorption gas chromatographic system with off-the-shelf components for monitoring ambient volatile organic compounds

et al. 2016

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“…In light of the fact that traffic emission is a major source of acetylene, Na and Kim [13] explained the relatively high A/THC ratio during winter as the result of a decrease in non-traffic source activities (e.g., gasoline evaporation and the use of solvents). The cause of such differences in temporal variation patterns was also studied in a Taiwanese urban area [22]. Due to a strong seasonality, temperature inversion is suspected to promote a maximum concentration of pollutants in the winter, while such an effect is not significant enough during the summer.…”

Section: Seasonal Variation Patterns Of Vocmentioning

confidence: 99%

Volatile organic compounds at an urban monitoring station in Korea

Nguyen

Kım

Kim³

2009

Journal of Hazardous Materials

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“…Variation in source strength has dominating influence on variations in VOC concentrations in close proximity to the source. However, when distance between source and receptor increases, meteorological parameters Yang et al, 2005;Cheng et al, 1997) and photochemical activity (Na and Kim, 2001) may become more important factors affecting variations in VOC concentrations. Diurnal, weekday-weekend, and seasonal variations in VOC concentrations measured in this study are discussed in the following.…”

Section: Temporal Variations Of Vocsmentioning

confidence: 99%

“…Reactions of VOCs with nitrogen oxides (NO x ) in the atmosphere result in formation of photochemical smog, which is known to harm both human health and ecosystems (Finlayson and Pitts, 1993;Lippmann, 1991). Both their toxicity and ozone-forming potential attracted attention on VOCs in the last decade and led to extensive measurements of their levels and assessment of their sources in urban airsheds in -different parts of the world (Srivastava et al, 2005;Yang et al, 2005;Na, Kim, and Moon, 2003;Pankow et al, 2003;Barletta et al, 2002;Bravo et al, 2002;Edwards et al, 2001;Liu et al, 2000). However, there are few measurements of VOCs in different urban and industrial areas in Turkey, including measurements performed at Izmir, (Müezzinoğlu,there are no major industries in the city.…”

Section: Introductionmentioning

confidence: 99%

C5–C12 volatile organic compounds at roadside, residential, and background locations in Ankara, Turkey: Temporal and spatial variations and sources

Kuntasal

Kılavuz

Karman

et al. 2013

Journal of the Air & Waste Management Association

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Concentrations of 91 volatile organic compounds (VOCs) ranging from C5 to C12 were measured at three sites in Ankara, the capital of Turkey, in the summer of 2003 and winter of 2004. Samples were collected at roadside, residential and background stations at consecutive 4-hr intervals over a 24-hr period for six weeks in each season. Air samples were collected onto cartridges packed with Tenax TA and Carbopack B resins and analyzed by thermal desorption, followed by gas chromatography coupled to a mass selective detector (GC/MSD). Time resolved data provided information on ambient levels, temporal and spatial variations and sources of VOCs in Ankara. Toluene is the most abundant compound at all sites with and average concentration of 13.1 ?g m-3. The mean concentrations of benzene are 12.6, 5.2, and 2.4 ?g m-3 during winter at roadside, residential and background stations, respectively. Diurnal variation in the data together with toluene to benzene concentration ratio (T:B) that is close to 2.0 indicated the influence of traffic related emissions at residential and roadside stations during winter season. Higher T:B ratio observed at residential and background stations during summer period and correlation analysis indicated additional VOC sources. Temporal variations and low m,p-xylene to ethylbenzene ratio (mpX:E) indicated that transported air mass is the major VOC source influencing VOC concentrations measured at the background station.Implications: VOC measurement at three sites in Ankara, the capital of Turkey showed that VOC concentrations measured at the roadside station are reasonably higher than concentrations measured at residential and background sites. Diurnal variations of VOC concentrations revealed that traffic emissions at roadside and residential locations are a significant VOC source in Ankara. On the other hand, VOC levels measured at the background site are transported from more polluted parts of Ankara.

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Diurnal and seasonal cycles of ozone precursors observed from continuous measurement at an urban site in Taiwan

Cited by 59 publications

References 29 publications

Construction of a cryogen-free thermal desorption gas chromatographic system with off-the-shelf components for monitoring ambient volatile organic compounds

Construction of a cryogen-free thermal desorption gas chromatographic system with off-the-shelf components for monitoring ambient volatile organic compounds

Volatile organic compounds at an urban monitoring station in Korea

C5–C12 volatile organic compounds at roadside, residential, and background locations in Ankara, Turkey: Temporal and spatial variations and sources

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