Till sidans topp

Sidansvarig: Webbredaktion
Sidan uppdaterades: 2012-09-11 15:12

Tipsa en vän
Utskriftsversion

Parameterization of Therm… - Göteborgs universitet Till startsida
Webbkarta
Till innehåll Läs mer om hur kakor används på gu.se

Parameterization of Thermal Properties of Aging Secondary Organic Aerosol Produced by Photo-Oxidation of Selected Terpene Mixtures

Artikel i vetenskaplig tidskrift
Författare Eva U. Emanuelsson
T. F. Mentel
Ågot Watne
C. Spindler
B. Bohn
T. Brauers
H. P. Dorn
Åsa M. Hallquist
R. Haseler
A. Kiendler-Scharr
K. P. Muller
Håkan Pleijel
F. Rohrer
F. Rubach
E. Schlosser
R. Tillmann
Mattias Hallquist
Publicerad i Environmental Science and Technology
Volym 48
Nummer/häfte 11
Sidor 6168-6176
ISSN 0013-936X
Publiceringsår 2014
Publicerad vid Institutionen för biologi och miljövetenskap
Institutionen för kemi och molekylärbiologi
Sidor 6168-6176
Språk en
Länkar dx.doi.org/10.1021/es405412p
Ämneskategorier Annan teknik

Sammanfattning

Formation and evolution of secondary organic aerosols (SOA) from biogenic VOCs influences the Earth's radiative balance. We have examined the photo-oxidation and aging of boreal terpene mixtures in the SAPHIR simulation chamber. Changes in thermal properties and chemical composition, deduced from mass spectrometric measurements, were providing information on the aging of biogenic SOA produced under ambient solar conditions. Effects of precursor mixture, concentration, and photochemical oxidation levels (OH exposure) were evaluated. OH exposure was found to be the major driver in the long term photochemical transformations, i.e., reaction times of several hours up to days, of SOA and its thermal properties, whereas the initial concentrations and terpenoid mixtures had only minor influence. The volatility distributions were parametrized using a sigmoidal function to determine T-VFR0.5 (the temperature yielding a 50% particle volume fraction remaining) and the steepness of the volatility distribution. T-VFR0.5 increased by 0.3 +/- 0.1% (ca. 1 K), while the steepness increased by 0.9 +/- 0.3% per hour of 1 x 10(6) cm(-3) OH exposure. Thus, aging reduces volatility and increases homogeneity of the vapor pressure distribution, presumably because highly volatile fractions become increasingly susceptible to gas phase oxidation, while less volatile fractions are less reactive with gas phase OH.

Sidansvarig: Webbredaktion|Sidan uppdaterades: 2012-09-11
Dela:

På Göteborgs universitet använder vi kakor (cookies) för att webbplatsen ska fungera på ett bra sätt för dig. Genom att surfa vidare godkänner du att vi använder kakor.  Vad är kakor?