Ozone, atmosphere pinene reactions

As exemplified by the stmctural formulas of a-pinene, P-pinene, A -carene, isoprene, and limonene, shown in Figure 16.1, terpenes contain alkenyl (olefinic) bonds, in some cases two or more per molecule. Because of these and other structural features, terpenes are among the most reactive compounds in the atmosphere. The reaction of terpenes with hydroxyl radical is very rapid, and terpenes also react with other oxidizing agents in the atmosphere, particularly ozone, O3. Turpentine, a mixture of terpenes, has been widely used in paint because it reacts with atmospheric oxygen to form a peroxide, then a hard resin. It is likely that compounds such as a-pinene and isoprene undergo similar reactions in the atmos-... 

Grosjean D, EL Williams, E Grosjean, JM Andino, JH Seinfeld (1993c) Atmospheric oxidation of biogenic hydrocarbons reaction of ozone with 3-pinene, D-limonene, and rra -caryophyllene. Environ Sci Technol 27 2754-2758. 

Organic aerosols formed by gas-phase photochemical reactions of hydrocarbons, ozone, and nitrogen oxides have been identified recently in both urban and rural atmospheres. Aliphatic organic nitrates, such dicarboxylic acids as adipic and glutaric acids, carboxylic acids derived from aromatic hydrocarbons (benzoic and phenylacetic acids) and from terpenes emitted by vegetation, such as pinonic acid from a pinene, have been identified. The most important contribution in this held has been that of Schuetzle et al., who used computer-controlled... 

Grosjean, D., E. L. Williams, II, E. Grosjean, J. M. Andino, and J. H. Seinfeld, Atmospheric Oxidation of Biogenic Hydrocarbons Reaction of Ozone with /J-Pinene, d-Limonene, and trans-Caryophyllene, Em iron. Sci. Techriol., 27, 2754-2758 (1993a). 

Chambers were also used in the research on heterogeneous reactions of isoprene and of other atmospheric trace compounds. As already discussed, Czoschke et al. (2003) studied the formation of SOA from products of isoprene oxidation in 500 dm Teflon-bag chambers at UNC. FoUcers et al. (2003a,b,c) studied the partitioning and influence of dicarboxylic acids on aerosol formation in Aerosol Chamber in Julich. Shantz et al. (2003) investigated the growth of aqueous organic particles and cloud condensation nuclei in the CALSPAN chamber, linuma et al. (2004 paper submitted to this book) studied the reaction of a-pinene with ozone on acidic particles in the Leipzig tent-chamber (9 m ). 

Grosjean, D., E.L. Williams, E. Grosjean, J.M. Andino, and J.H. Seinfeld. 1993c. Atmospheric oxidation of biogenic hydrocarbons reaction of ozone with [i-pinene, D-liminene, and frans-caryophyllene. Environ. Sci. Technol. rZ7 2754—2758. Grosser, R.J., D. Warshawsky, and J.R. Vestal. 1991. Indigenous and enhanced mineralization of pyrene, benzo[a]pyene, and carbazole in soils. Appl. Environ. Microbiol. 57 3462-3469. 

Biogenic hydrocarbons are principally emitted by trees. Isoprene and a- and /3-pinene are the most abundant biogenic hydrocarbons which are emitted (Dimitriades, 1981) (see Fig. 7). The rate constants of the reactions of the biogenics with OH, ozone, and nitrate radicals have been well investigated (Atkinson, 1991 Atkinson et ai, 1990). However, limited data are available concerning the products of biogenic reactions in the atmosphere. 

Amts et al. (1982) have measured the dispersion of alpha-pinene from a loblolly pine forest with the help of SF6, which was released inside the forest and served as a tracer for air motions. Both SF6 and alpha-pinene were measured downwind at a number of receptor sites. An atmospheric plume dispersion model was used to describe the observations and to infer emission rates. Losses of alpha-pinene due to reactions with ozone and OH radicals were incorporated into the model. Emission rates derived ranged from 11 to 19 pg/m2 min. No direct comparison was made with the rate of alpha-pinene emissions from three branches by the bag enclosure technique. Instead, available data from Rasmussen (1972) and Zimmerman (1979b) were used to estimate the rate expected for this particular forest site at the temperatures encountered during the measurements. The values obtained were 14-35 p.g/m2 min and 47 p.g/m2 min, respectively. Although the alpha-pinene fluxes inferred from the tracer release approach are lower, the differences are not great enough in view of the large variability of actual emission rates to raise doubts about the applicability of the bag enclosure technique. 

Because of their double bonds, isoprene and a-pinene are Ukely to react with ozone (Weschler and Shields, 1999). These reactions may cause a difference between indoor and outdoor atmospheric chemistry, since these compounds have known indoor sources. An important product from these reactions may be the far more reactive OH- radical (Atkinson et al., 1992 Weschler and Shields, 1996). 

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