Evaluating the Mixing of Organic Aerosol Components Using High-Resolution Aerosol Mass Spectrometry

2011 ◽  
Vol 45 (15) ◽  
pp. 6329-6335 ◽  
Author(s):  
Lea Hildebrandt ◽  
Kaytlin M. Henry ◽  
Jesse H. Kroll ◽  
Douglas R. Worsnop ◽  
Spyros N. Pandis ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
High Resolution ◽  
Organic Aerosol ◽  
Aerosol Mass ◽  
Aerosol Mass Spectrometry

scholarly journals Evaluating the degree of oxygenation of organic aerosol during foggy and hazy days in Hong Kong using high-resolution time-of-flight aerosol mass spectrometry (HR-ToF-AMS)

2013 ◽  
Vol 13 (2) ◽  
pp. 3533-3573 ◽  
Author(s):  
Y. J. Li ◽  
B. Y. L. Lee ◽  
J. Z. Yu ◽  
N. L. Ng ◽  
C. K. Chan
Keyword(s):  
Mass Spectrometry ◽  
Hong Kong ◽  
High Resolution ◽  
Time Of Flight ◽  
Organic Aerosol ◽  
Present Observation ◽  
Particle Phase ◽  
Resolution Time ◽  
Aerosol Mass ◽  
Aerosol Mass Spectrometry

Abstract. The chemical characteristics of organic aerosol (OA) are still poorly constrained. Here we present observation results of the degree of oxygenation of OA based on high-resolution time-of-flight aerosol mass spectrometry (HR-ToF-AMS) measurements made at a coastal site in Hong Kong from late April to the end of May in 2011. Two foggy periods and one hazy period were chosen for detailed analysis to compare the changes in the degree of oxygenation of OA due to different processes. The Extended Aerosol Inorganic Model (E-AIM) predicted a fine particle liquid water content (LWCfp) up to 85 μg m−3 during the foggy days. Particle concentration as measured by HR-ToF-AMS was up to 60 μg m−3 during the hazy days and up to 30 μg m−3 during the foggy days. The degree of oxygenation of OA, as indicated by several parameters including the fraction of m/z 44 in organic mass spectra (f44), the elemental ratio of oxygen to carbon (O : C), and the carbon oxidation state (OSc), was evaluated against the odd oxygen (Ox) concentration, LWCfp, ionic strength (IS), and in-situ pH (pHis). Results suggest that the high concentration of OA (on average 11 μg m−3) and the high degree of oxygenation (f44 = 0.15, O : C = 0.51, and OSc = −0.31) during the hazy period were mainly due to gas-phase oxidation. During the foggy periods with low photochemical activities, the degree of oxygenation of OA was almost as high as that on the hazy days and significantly higher than that during non-foggy/non-hazy days. However, the OA evolved quite differently in the two foggy periods. The first foggy period in late April saw a larger LWCfp and a lower Ox concentration and the OA was made up of ~ 20% semi-volatile oxygenated organic aerosol (SVOOA) as resolved by positive matrix factorization (PMF). In the second foggy period in mid-May, higher Ox concentration and lower LWCfp were observed, and the OA was found to contain >50% low-volatility oxygenated organic aerosols (LVOOA). An examination of the particle-phase constituents suggests that partitioning may have been the dominating process through which oxygenated species were incorporated into the particle phase during the first foggy period, while oxidation in the aqueous phase may have been the dominating process during the second foggy period. Both physical and chemical processes were found to be important for oxygenated OA formation.

scholarly journals On-line measurement of organic aerosol elemental composition based on high resolution aerosol mass spectrometry

2010 ◽  
Vol 55 (35) ◽  
pp. 3391-3396 ◽  
Author(s):  
YuanHang ZHU Tong ZHANG ◽  
彤 朱 ◽  
Min HU ◽  
Lian XUE ◽  
XiaoFeng HUANG ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
High Resolution ◽  
Elemental Composition ◽  
Organic Aerosol ◽  
Aerosol Mass ◽  
Aerosol Mass Spectrometry ◽  
Line Measurement ◽  
On Line

scholarly journals Evaluating the degree of oxygenation of organic aerosol during foggy and hazy days in Hong Kong using high-resolution time-of-flight aerosol mass spectrometry (HR-ToF-AMS)

2013 ◽  
Vol 13 (17) ◽  
pp. 8739-8753 ◽  
Author(s):  
Y. J. Li ◽  
B. Y. L. Lee ◽  
J. Z. Yu ◽  
N. L. Ng ◽  
C. K. Chan
Keyword(s):  
Mass Spectrometry ◽  
Hong Kong ◽  
High Resolution ◽  
Gas Phase ◽  
Time Of Flight ◽  
Organic Aerosol ◽  
Resolution Time ◽  
Aerosol Mass ◽  
Aerosol Mass Spectrometry ◽  
Inorganic Species

Abstract. The chemical characteristics of organic aerosol (OA) are still poorly constrained. Here we present observation results of the degree of oxygenation of OA based on high-resolution time-of-flight aerosol mass spectrometry (HR-ToF-AMS) measurements made at a coastal site in Hong Kong from late April to the end of May in 2011. Two foggy periods and one hazy period were chosen for detailed analysis to compare the changes in the degree of oxygenation of OA due to different processes. Using HR-ToF-AMS measured inorganic species as input, the Extended Aerosol Inorganic Model (E-AIM) predicted a fine-particle liquid water content (LWCfp) up to 85 μg m−3 during the foggy days. Particle concentration as measured by HR-ToF-AMS was up to 60 μg m−3 during the hazy days and up to 30 μg m−3 during the foggy days. The degree of oxygenation of OA, as indicated by several parameters including the fraction of m/z 44 in organic mass spectra (f44), the elemental ratio of oxygen to carbon (O : C), and the carbon oxidation state (OSc), was evaluated against the odd oxygen (Ox) concentration, LWCfp, ionic strength (IS), and in situ pH (pHis). Observations suggest that the high concentration of OA (on average 11 μg m−3) and the high degree of oxygenation (f44 = 0.15, O : C = 0.51, and OSc = −0.31) during the hazy period were mainly due to gas-phase oxidation. During the foggy periods with low photochemical activities, the degree of oxygenation of OA was almost as high as that on the hazy days, and significantly higher than that during non-foggy/non-hazy days. However, the OA evolved quite differently in the two foggy periods. The first foggy period in late April saw a larger LWCfp and a lower Ox concentration and the OA were made up of ~ 20 % semi-volatile oxygenated organic aerosol (SVOOA) as resolved by positive matrix factorization (PMF). In the second foggy period in mid-May, higher Ox concentration and lower LWCfp were observed, and the OA were found to contain > 50 % low-volatility oxygenated organic aerosols (LVOOA). An examination of the particle characteristics (pHis, IS, and LWCfp) suggests that partitioning may have been the dominating process through which oxygenated species were incorporated into the particle phase during the first foggy period, while oxidation in the aqueous phase dominated over gas-phase processes during the second foggy period.

Identification of amines in wintertime ambient particulate material using high resolution aerosol mass spectrometry

2018 ◽  
Vol 180 ◽  
pp. 173-183 ◽  
Author(s):  
Courtney L.H. Bottenus ◽  
Paola Massoli ◽  
Donna Sueper ◽  
Manjula R. Canagaratna ◽  
Graham VanderSchelden ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
High Resolution ◽  
Particulate Material ◽  
Aerosol Mass ◽  
Aerosol Mass Spectrometry

Aerosol Chemical Composition in Cloud Events by High Resolution Time-of-Flight Aerosol Mass Spectrometry

2013 ◽  
Vol 47 (6) ◽  
pp. 2645-2653 ◽  
Author(s):  
Liqing Hao ◽  
Sami Romakkaniemi ◽  
Aki Kortelainen ◽  
Antti Jaatinen ◽  
Harri Portin ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Chemical Composition ◽  
High Resolution ◽  
Time Of Flight ◽  
Resolution Time ◽  
Aerosol Mass ◽  
Aerosol Mass Spectrometry ◽  
Aerosol Chemical Composition

scholarly journals Rural continental aerosol properties and processes observed during the Hohenpeissenberg Aerosol Characterization Experiment (HAZE2002)

2007 ◽  
Vol 7 (3) ◽  
pp. 8617-8662 ◽  
Author(s):  
N. Hock ◽  
J. Schneider ◽  
S. Borrmann ◽  
A. Römpp ◽  
G. Moortgat ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Particle Number ◽  
Dicarboxylic Acids ◽  
Organic Aerosol ◽  
Particle Formation ◽  
Total Carbon ◽  
Submicron Particles ◽  
Aerosol Mass ◽  
Aerosol Mass Spectrometry ◽  
Meteorological Observatory

Abstract. Detailed investigations of the chemical and microphysical properties of rural continental aerosols were performed during the HAZE2002 experiment, which was conducted in May 2002 at the Meteorological Observatory Hohenpeissenberg (DWD) in Southern Germany. The online measurement data and techniques included: size-resolved chemical composition of submicron particles by aerosol mass spectrometry (AMS); total particle number concentrations and size distributions over the diameter range of 3 nm to 9 μm (CPC, SMPS, OPC); monoterpenes determined by gas chromatography- ion trap mass spectrometry; OH and H2SO4 determined by atmospheric pressure chemical ionization mass spectrometry (CIMS). Filter sampling and offline analytical techniques were used to determine: fine particle mass (PM2.5), organic, elemental and total carbon in PM2.5 (OC2.5, EC2.5, TC2.5), and selected organic compounds (dicarboxylic acids, polycyclic aromatic hydrocarbons, proteins). Overall, the non-refractory components of submicron particles detected by aerosol mass spectrometry (PM1, 6.6±5.4 μg m−3, arithmetic mean and standard deviation) accounted for ~62% of PM2.5 determined by filter gravimetry (10.6±4.7 μg m−3). The relative proportions of non-refractory submicron particle components were: 11% ammonium, 19% nitrate, 20% sulfate, and 50% organics (OM1). In spite of strongly changing meteorological conditions and absolute concentration levels of particulate matter (3–13 μg m−3 PM1), OM1 was closely correlated with PM1 (r2=0.9) indicating a near-constant ratio of non-refractory organics and inorganics. In contrast, the ratio of nitrate to sulfate was highly dependent on temperature (14–32°C) and relative humidity (20–100%), which could be explained by thermodynamic model calculations of NH3/HNO3/NH4NO3 gas-particle partitioning. From the combination of optical and other sizing techniques (OPC, AMS, SMPS), an average refractive index of 1.40–1.45 was inferred for the measured rural aerosol particles. The average ratio of OM1 to OC2.5 was 2, indicating a high proportion of heteroelements in the organic fraction of the sampled rural aerosol. This is consistent with the high ratio of oxygenated organic aerosol (OOA) over hydrocarbon-like organic aerosol (HOA) inferred from the AMS results (4:1), and also with the high abundance of proteins (~3%) indicating a high proportion of primary biological material (~30%) in PM2.5. Moreover, the low abundance of PAHs (<1 ng m−3) and EC (<1 μg m−3) in PM2.5 confirm a low contribution of combustion emissions, which are usually also major sources for HOA. Slightly enhanced HOA concentrations indicating fresh anthropogenic emissions were observed during a period when air masses were advected from the densely populated Po Valley, Italy. Detection of several secondary organic aerosol compounds (dicarboxylic acids) and their precursors (monoterpenes) confirmed the finding that secondary aerosol from natural sources was an important aerosol constituent. A sharp decrease of the short lived monoterpenes indicated that during night-time the measurement station was isolated from ground emission sources by a stable inversion layer. Nighttime values can therefore be regarded to represent regional or long range transport. New particle formation was observed almost every day with particle number concentrations exceeding 104 cm−3 (nighttime background level 1000–2000 cm−3). Closer inspection of two major events indicated that ternary H2SO4/H2O/NH3 nucleation triggered particle formation and that condensation of both organic and inorganic species contributed to particle growth.

Sign in / Sign up

Export Citation Format

Share Document