Particle composition, sources and evolution during the COVID-19 lockdown period in Chengdu, southwest China: Insights from single particle aerosol mass spectrometer data

Abstract. A light-scattering module was coupled to an airborne, compact time-of-flight aerosol mass spectrometer (LS-AMS) to investigate collection efficiency (CE) while obtaining nonrefractory aerosol chemical composition measurements during the Southeast Nexus (SENEX) campaign. In this instrument, particles scatter light from an internal laser beam and trigger saving individual particle mass spectra. Nearly all of the single-particle data with mass spectra that were triggered by scattered light signals were from particles larger than ∼ 280 nm in vacuum aerodynamic diameter. Over 33 000 particles are characterized as either prompt (27 %), delayed (15 %), or null (58 %), according to the time and intensity of their total mass spectral signals. The particle mass from single-particle spectra is proportional to that derived from the light-scattering diameter (dva-LS) but not to that from the particle time-of-flight (PToF) diameter (dva-MS) from the time of the maximum mass spectral signal. The total mass spectral signal from delayed particles was about 80 % of that from prompt ones for the same dva-LS. Both field and laboratory data indicate that the relative intensities of various ions in the prompt spectra show more fragmentation compared to the delayed spectra. The particles with a delayed mass spectral signal likely bounced off the vaporizer and vaporized later on another surface within the confines of the ionization source. Because delayed particles are detected by the mass spectrometer later than expected from their dva-LS size, they can affect the interpretation of particle size (PToF) mass distributions, especially at larger sizes. The CE, measured by the average number or mass fractions of particles optically detected that had measurable mass spectra, varied significantly (0.2–0.9) in different air masses. The measured CE agreed well with a previous parameterization when CE > 0.5 for acidic particles but was sometimes lower than the minimum parameterized CE of 0.5.

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The real part of the refractive indices and effective densities for chemically segregated ambient aerosols in Guangzhou measured by a single-particle aerosol mass spectrometer

Atmospheric Chemistry and Physics ◽

10.5194/acp-16-2631-2016 ◽

2016 ◽

Vol 16 (4) ◽

pp. 2631-2640 ◽

Cited By ~ 6

Author(s):

Guohua Zhang ◽

Xinhui Bi ◽

Ning Qiu ◽

Bingxue Han ◽

Qinhao Lin ◽

...

Keyword(s):

Mass Spectrometer ◽

Atmospheric Aerosols ◽

Single Particle ◽

Refractive Indices ◽

Chemical Compositions ◽

Aerosol Mass Spectrometer ◽

The Real ◽

Aerosol Mass ◽

Wide Range ◽

The Impact

Abstract. Knowledge on the microphysical properties of atmospheric aerosols is essential to better evaluate their radiative forcing. This paper presents an estimate of the real part of the refractive indices (n) and effective densities (ρeff) of chemically segregated atmospheric aerosols in Guangzhou, China. Vacuum aerodynamic diameter, chemical compositions, and light-scattering intensities of individual particles were simultaneously measured by a single-particle aerosol mass spectrometer (SPAMS) during the fall of 2012. On the basis of Mie theory, n at a wavelength of 532 nm and ρeff were estimated for 17 particle types in four categories: organics (OC), elemental carbon (EC), internally mixed EC and OC (ECOC), and Metal-rich. The results indicate the presence of spherical or nearly spherical shapes for the majority of particle types, whose partial scattering cross-section versus sizes were well fitted to Mie theoretical modeling results. While sharing n in a narrow range (1.47–1.53), majority of particle types exhibited a wide range of ρeff (0.87–1.51 g cm−3). The OC group is associated with the lowest ρeff (0.87–1.07 g cm−3), and the Metal-rich group with the highest ones (1.29–1.51 g cm−3). It is noteworthy that a specific EC type exhibits a complex scattering curve versus size due to the presence of both compact and irregularly shaped particles. Overall, the results on the detailed relationship between physical and chemical properties benefits future research on the impact of aerosols on visibility and climate.

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Mass spectra features of biomass burning boiler and coal burning boiler emitted particles by single particle aerosol mass spectrometer

The Science of The Total Environment ◽

10.1016/j.scitotenv.2017.04.132 ◽

2017 ◽

Vol 598 ◽

pp. 341-352 ◽

Cited By ~ 14

Author(s):

Jiao Xu ◽

Mei Li ◽

Guoliang Shi ◽

Haiting Wang ◽

Xian Ma ◽

...

Keyword(s):

Mass Spectrometer ◽

Biomass Burning ◽

Single Particle ◽

Mass Spectra ◽

Aerosol Mass Spectrometer ◽

Coal Burning ◽

Aerosol Mass

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Analysis of Cigarette Smoke Aerosol by Single Particle Aerosol Mass Spectrometer

Chinese Journal of Analytical Chemistry ◽

10.1016/s1872-2040(11)60555-0 ◽

2012 ◽

Vol 40 (6) ◽

pp. 936-939 ◽

Cited By ~ 9

Author(s):

Mei LI ◽

Jun-Guo DONG ◽

Zheng-Xu HUANG ◽

Lei LI ◽

Wei GAO ◽

...

Keyword(s):

Cigarette Smoke ◽

Mass Spectrometer ◽

Single Particle ◽

Aerosol Mass Spectrometer ◽

Smoke Aerosol ◽

Aerosol Mass

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An aerosol mass spectrometer for quantitative on-line sampling of particle composition

Journal of Aerosol Science ◽

10.1016/s0021-8502(00)90353-7 ◽

2000 ◽

Vol 31 ◽

pp. 342-343

Author(s):

H. Coe ◽

P.I. Williams ◽

M.W. Gallagher ◽

K.N. Bower ◽

T.W. Choularton ◽

...

Keyword(s):

Mass Spectrometer ◽

Particle Composition ◽

Aerosol Mass Spectrometer ◽

Aerosol Mass ◽

Line Sampling ◽

On Line

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Elemental analysis of chamber organic aerosol using an aerodyne high-resolution aerosol mass spectrometer

Atmospheric Chemistry and Physics ◽

10.5194/acp-10-4111-2010 ◽

2010 ◽

Vol 10 (9) ◽

pp. 4111-4131 ◽

Cited By ~ 132

Author(s):

P. S. Chhabra ◽

R. C. Flagan ◽

J. H. Seinfeld

Keyword(s):

High Resolution ◽

Elemental Composition ◽

Mass Spectrometer ◽

Organic Aerosol ◽

Uptake System ◽

Aerosol Mass Spectrometer ◽

Aerosol Mass ◽

Single Ring ◽

Spectrometer Data ◽

Ambient Measurements

Abstract. The elemental composition of laboratory chamber secondary organic aerosol (SOA) from glyoxal uptake, α-pinene ozonolysis, isoprene photooxidation, single-ring aromatic photooxidation, and naphthalene photooxidation is evaluated using Aerodyne high-resolution time-of-flight mass spectrometer data. SOA O/C ratios range from 1.13 for glyoxal uptake experiments to 0.30–0.43 for α-pinene ozonolysis. The elemental composition of α-pinene and naphthalene SOA is also confirmed by offline mass spectrometry. The fraction of organic signal at m/z 44 is generally a good measure of SOA oxygenation for α-pinene/O3, isoprene/high-NOx, and naphthalene SOA systems. The agreement between measured and estimated O/C ratios tends to get closer as the fraction of organic signal at m/z 44 increases. This is in contrast to the glyoxal uptake system, in which m/z 44 substantially underpredicts O/C. Although chamber SOA has generally been considered less oxygenated than ambient SOA, single-ring aromatic- and naphthalene-derived SOA can reach O/C ratios upward of 0.7, well within the range of ambient PMF component OOA, though still not as high as some ambient measurements. The spectra of aromatic and isoprene-high-NOx SOA resemble that of OOA, but the spectrum of glyoxal uptake does not resemble that of any ambient organic aerosol PMF component.

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CHEMICAL COMPOSITION OF AEROSOLS IN THE WEST COAST OF TAIWAN STRAIT, CHINA

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-3-w9-233-2019 ◽

2019 ◽

Vol XLII-3/W9 ◽

pp. 233-237

Author(s):

L. Zhao ◽

C. Yang

Keyword(s):

Chemical Composition ◽

Mass Spectrometer ◽

Single Particle ◽

Inorganic Ions ◽

Water Soluble ◽

Ion Concentration ◽

Aerosol Mass Spectrometer ◽

Average Mass ◽

Inorganic Ion ◽

Aerosol Mass

Abstract. The chemical composition of aerosols was investigated using regular environmental air quality observation, a single particle aerosol mass spectrometer (SPAMS 0515) and an ambient ion monitor (URG 9000D) in Xiamen in 2018. The results showed that the annual average mass concentrations of PM2.5 was 22 μm/m3, and concentrations of water-soluble inorganic ions was 9.94 μm/m3 which accounted for 45.2% of PM2.5. SO42−, NO3− and NH4+ were main components of secondary reactions which contributed more than 77 percent of water-soluble inorganic ion concentration. As a coastal city, Cl− and Na+ contributed 13.9 percent of water-soluble inorganic ion concentration. Based on single particle aerosol mass spectrometer analysing, mobile sources emission was the most important sources of particle matter which contributed over 30%.

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Receptor modeling of near-roadway aerosol mass spectrometer data in Las Vegas, Nevada, with EPA PMF

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-11-22909-2011 ◽

2011 ◽

Vol 11 (8) ◽

pp. 22909-22950 ◽

Cited By ~ 2

Author(s):

S. G. Brown ◽

T. Lee ◽

G. A. Norris ◽

P. T. Roberts ◽

J. L. Collett ◽

...

Keyword(s):

Mass Spectrometer ◽

Las Vegas ◽

Organic Aerosol ◽

Receptor Modeling ◽

Factor Solution ◽

Aerosol Mass Spectrometer ◽

Source Profiles ◽

Aerosol Mass ◽

The Us ◽

Spectrometer Data

Abstract. Ambient non-refractory PM1 aerosol particles were measured with an Aerodyne High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-AMS) at an elementary school 20 m from the US 95 freeway in Las Vegas, Nevada, during January 2008. Additional collocated continuous measurements of black carbon (BC), carbon monoxide (CO), nitrogen oxides (NOx), and meteorological data were collected. The US Environmental Protection Agency's (EPA) positive matrix factorization (PMF) data analysis tool was used to apportion organic matter (OM) as measured by HR-AMS, and rotational tools in EPA PMF were used to better characterize the solution space and pull resolved factors toward known source profiles. Three- to six-factor solutions were resolved. The four-factor solution was the most interpretable, with the typical AMS PMF factors of hydrocarbon-like organic aerosol (HOA), low-volatility oxygenated organic aerosol (LV-OOA), biomass burning organic aerosol (BBOA), and semi-volatile oxygenated organic aerosol (SV-OOA). When the measurement site was downwind of the freeway, HOA composed about half the OM, with SV-OOA and LV-OOA accounting for the rest. Attempts to pull the PMF factor profiles toward source profiles were successful but did not qualitatively change the results, indicating that these factors are very stable. Oblique edges were present in G-space plots, suggesting that the obtained rotation may not be the most plausible one. Since solutions found by pulling the profiles or using Fpeak retained these oblique edges, there appears to be little rotational freedom in the base solution. On average, HOA made up 26 % of the OM, and it made up nearly half of the OM when the monitoring site was downwind of US 95 during morning rush hour. LV-OOA was highest in the afternoon and accounted for 26 % of the OM. BBOA occurred in the evening hours, was predominantly from the residential area to the north, and on average constituted 12 % of the OM; SV-OOA accounted for the remaining third of the OM. Use of the pulling techniques available in EPA PMF and ME-2 suggested that the four-factor solution was very stable.

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Quantitative single particle analysis with the Aerodyne aerosol mass spectrometer: development of a new classification algorithm and its application to field data

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-6-5653-2013 ◽

2013 ◽

Vol 6 (3) ◽

pp. 5653-5691 ◽

Cited By ~ 1

Author(s):

F. Freutel ◽

F. Drewnick ◽

J. Schneider ◽

T. Klimach ◽

S. Borrmann

Keyword(s):

Mass Spectrometer ◽

Single Particle ◽

Field Data ◽

Classification Algorithm ◽

Particle Mass ◽

Submicron Particles ◽

Particle Analysis ◽

Mixing State ◽

Aerosol Mass Spectrometer ◽

Aerosol Mass

Abstract. Single particle mass spectrometry has proven a valuable tool for gaining information on the mixing state of aerosol particles. With the Aerodyne aerosol mass spectrometer (AMS) equipped with a light scattering probe, non-refractory components of submicron particles with diameters larger than about 300 nm can even be quantified on a single particle basis. Here, we present a new method for the analysis of AMS single particle mass spectra. The developed algorithm classifies the particles according to their components (e.g., sulphate, nitrate, different types of organics) and simultaneously provides quantitative information about the composition of the single particles. This classification algorithm was validated by applying it to data acquired in laboratory experiments with particles of known composition, and applied to field data acquired during the MEGAPOLI summer campaign (July 2009) in Paris. As shown, it is not only possible to directly measure the mixing state of atmospheric particles, but also to directly observe repartitioning of semi-volatile species between gas and particle phase during the course of the day.

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