Atmospheric Chemistry and Physics Discussions
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2002
10.5194/acpd-2-469-2002
http://www.atmos-chem-phys-discuss.net/2/469/2002/
http://www.atmos-chem-phys-discuss.net/2/469/2002/acpd-2-469-2002.html
http://www.atmos-chem-phys-discuss.net/2/469/2002/acpd-2-469-2002.pdf
469
506
2002-04-19
New particle formation during α- and β-pinene oxidation by O<sub>3</sub>, OH and NO<sub>3</sub>, and the influence of water vapour: particle size distribution studies
B. Bonn
G. K. Moortgat
Max-Planck-Institut für Chemie, Atmospheric Chemistry Division, Mainz, Germany
New particle formation during the oxidation of
<font face="Symbol" >a</font>- and
<font face="Symbol" >b</font>-pinene
(C<sub>10</sub>H<sub>16</sub>) by ozone, OH and NO<sub>3</sub> was studied by measuring the particle size
distributions with a scanning mobility particle sizer (TSI 3936). The results indicate a drastically higher nucleation potential of
the ozonolysis than in the reaction with either OH or NO<sub>3</sub>. On the contrary, the contribution of the individual
oxidation reactions to form new aerosol volume was found to depend on the location of the carbon double bond to be oxidized: for the
<i>endocyclic</i> <font face="Symbol" >a</font>-pinene reactions the ozonolysis
contributed mostly to the aerosol volume yield, whereas for the <i>exocyclic</i>
<font face="Symbol" >b</font>-pinene reactions the oxidation
by O<sub>3</sub>, OH and NO<sub>3</sub> yielded a similar aerosol volume.<br>
<br>
In a second part of this study the influence of water vapour on the nucleation in all three possible oxidation routes was
examined. The observations revealed only an effect of water vapour during the ozonolysis reactions.