Spatial Distribution of Secondary Organic Aerosol Formation Potential in China Derived from Speciated Anthropogenic Volatile Organic Compound Emissions

2018 ◽  
Vol 52 (15) ◽  
pp. 8146-8156 ◽  
Author(s):  
Rongrong Wu ◽  
Shaodong Xie
Keyword(s):  
Spatial Distribution ◽  
Organic Compound ◽  
Volatile Organic Compound ◽  
Secondary Organic Aerosol ◽  
Organic Aerosol ◽  
Aerosol Formation ◽  
Formation Potential ◽  
Volatile Organic ◽  
Volatile Organic Compound Emissions ◽  
Secondary Organic Aerosol Formation

scholarly journals Temperature and volatile organic compound concentrations as controlling factors for chemical composition of <i>α</i>-pinene-derived secondary organic aerosol

2021 ◽  
Vol 21 (15) ◽  
pp. 11545-11562
Author(s):  
Louise N. Jensen ◽  
Manjula R. Canagaratna ◽  
Kasper Kristensen ◽  
Lauriane L. J. Quéléver ◽  
Bernadette Rosati ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Organic Compound ◽  
Organic Acids ◽  
Organic Acid ◽  
Elemental Composition ◽  
Volatile Organic Compound ◽  
Secondary Organic Aerosol ◽  
Organic Aerosol ◽  
Oxidation Level ◽  
Volatile Organic

Abstract. This work investigates the individual and combined effects of temperature and volatile organic compound precursor concentrations on the chemical composition of particles formed in the dark ozonolysis of α-pinene. All experiments were conducted in a 5 m3 Teflon chamber at an initial ozone concentration of 100 ppb and initial α-pinene concentrations of 10 and 50 ppb, respectively; at constant temperatures of 20, 0, or −15 ∘C; and at changing temperatures (ramps) from −15 to 20 and from 20 to −15 ∘C. The chemical composition of the particles was probed using a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). A four-factor solution of a positive matrix factorization (PMF) analysis of the combined HR-ToF-AMS data is presented. The PMF analysis and the elemental composition analysis of individual experiments show that secondary organic aerosol particles with the highest oxidation level are formed from the lowest initial α-pinene concentration (10 ppb) and at the highest temperature (20 ∘C). A higher initial α-pinene concentration (50 ppb) and/or lower temperature (0 or −15 ∘C) results in a lower oxidation level of the molecules contained in the particles. With respect to the carbon oxidation state, particles formed at 0 ∘C are more comparable to particles formed at −15 ∘C than to those formed at 20 ∘C. A remarkable observation is that changes in temperature during particle formation result in only minor changes in the elemental composition of the particles. Thus, the temperature at which aerosol particle formation is induced seems to be a critical parameter for the particle elemental composition. Comparison of the HR-ToF-AMS-derived estimates of the content of organic acids in the particles based on m/z 44 in the mass spectra show good agreement with results from off-line molecular analysis of particle filter samples collected from the same experiments. Higher temperatures are associated with a decrease in the absolute mass concentrations of organic acids (R-COOH) and organic acid functionalities (-COOH), while the organic acid functionalities account for an increasing fraction of the measured particle mass.

Sign in / Sign up

Export Citation Format

Share Document