Peroxyacetyl nitrate (PAN) and peroxypropionyl nitrate (PPN) in urban and suburban atmospheres of Beijing, China

Abstract

Peroxyacetyl nitrate (PAN) and peroxypropionyl nitrate (PPN) were measured sequentially in situ by an online gas-phase chromatograph with electron capture detector at urban (Peking University, PKU) and suburban (Yufa, A town in the south of Beijing) sites in Beijing during the photochemical season in 2006. Maximum and average values of PAN were 11.22 ppbv and 1.95 ppbv at PKU during 15 to 27 August, and maximum and average values of PPN were 2.51 ppbv and 0.41 ppbv at Yufa during 2 to 12 September. Average mixing ratios (PAN/PPN) were 5.60 (at PKU) and 5.83 (at Yufa), which is much lower than those in other metropolitan areas. High correlation between PAN and PPN reflects similar volatile organic compound origins. Thermal loss of PAN and PPN was remarkable when compared with their ambient concentrations. PAN and PPN with ozone have similar trend by day. Thermal decompositions of PAN and PPN were calculated, and results indicated that thermal losses influence their atmospheric lifetime significantly. The percentages of PAN loss at the two sites were very similar; however, PPN urban loss was higher than that in suburban

Seasonal and diurnal variations of atmospheric peroxyacetyl nitrate, peroxypropionyl nitrate, and carbon tetrachloride in Beijing

“…The ΔO 3 /ΔPAN values obtained by this study in the summer months were 9.92-18.0, which were close to the value of 18.87 reported by Zhang et al (2011) in August 2006 in Beijing, but were generally lower than the values reported in other cities (e.g. 24.3 reported at an urban site of Ontario by Shepson et al, 1992), in forest regions (e.g., 38.2-81.9 reported by Pippin et al, 2001), and at rural sites (e.g.…”

“…PAN, as the most abundant species among PANs, has been recognized as lachrymators (Altshuller, 1978), mutagens (Shepson et al, 1986), and phytotoxins (Sun and Huang, 1995;Taylor, 1969). PPN as the second largest species among PANs, its atmospheric concentration usually accounts for 4%-20% of PAN (Grosjean et al, 2001(Grosjean et al, , 2002Lee et al, 2008;Zhang et al, 2011), and it is four times phytotoxic (Kleindienst et al, 1990) and five times eye-irritant than that of PAN (Altshuller, 1978). Furthermore, PAN and some of its analogues have been found to 10-50 times toxic to the plant than that of O 3 Marley, 2001a, 2001b;Taylor, 1969).…”

“…However, the measurements of PANs as the indicator of photochemical pollution, in the megacity are relatively sparse (Wang and Zhang, 2007;Yang et al, 2009;Zhang et al, 2011), and the existing studies mostly carried out over short period during summer, generally a few weeks.…”

Equipment for Diluting Air Pollution

“…Oxidants can kill plant cells, causing leaves to develop brown spots or drop off the plant, reduce plant growth, and make plants more susceptible to damage from other causes. Oxidants such as ozone can also corrode and destroy many materials such as rubber, nylon, fabric, and paint [3].…”

Decoupling peroxyacetyl nitrate from ozone in Chinese outflows observed at Gosan Climate Observatory

“…As thermal decomposition is a major PAN sink in the troposphere (Beine et al, 1997;Jacob, 2000;Kenley and Hendry, 1982;Talukdar et al, 1995), the lifetime of PAN depends on temperature. For example, the PAN lifetime is ∼ 5 years at −26 • C and 1 h at 20 • C (Fischer et al, 2010;Zhang et al, 2011). At high altitudes above ∼ 7 km, photolysis becomes the most important loss process for PAN (Talukdar et al, 1995).…”