Chemical characterization of submicron aerosol in summertime Beijing: A case study in southern suburbs in 2018

<p>The mechanical behavior of a natural stone ventilated facade is inevitably based on the correct execution of both anchoring elements, stone cladding and enclosure support, either with brick masonry walls or reinforced concrete walls. In the case studied in the present work, the origin of the damages on the facade of&#160;a building located in Lisbon has been analyzed,&#160;where stone detachments were starting to occur. This enclosure is a ventilated facade cladded with Portuguese limestone Lioz slabs. Non-destructive borescope analysis of the metallic anchoring system employed was performed, as well as X-Ray fluorescence laboratory analysis (FRX) for chemical characterization of the anchoring material. Results obtained demonstrated the problem cause on the stone facade due to incorrect metallic anchoring selection and poor execution combined with stress corrosion effect, especially for slabs with larger dimensions.</p>

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Counterflow Virtual Impactor Based Collection of Small Ice Particles in Mixed-Phase Clouds for the Physico-Chemical Characterization of Tropospheric Ice Nuclei: Sampler Description and First Case Study

Aerosol Science and Technology ◽

10.1080/02786820701501881 ◽

2007 ◽

Vol 41 (9) ◽

pp. 848-864 ◽

Cited By ~ 58

Author(s):

S. Mertes ◽

B. Verheggen ◽

S. Walter ◽

P. Connolly ◽

M. Ebert ◽

...

Keyword(s):

Chemical Characterization ◽

Mixed Phase ◽

Ice Nuclei ◽

Ice Particles ◽

Virtual Impactor ◽

First Case ◽

Physico Chemical ◽

Mixed Phase Clouds

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Chemical characterization of submicron regional background aerosols in the Western Mediterranean using an Aerosol Chemical Speciation Monitor

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-15-965-2015 ◽

2015 ◽

Vol 15 (1) ◽

pp. 965-1000 ◽

Cited By ~ 5

Author(s):

M. C. Minguillón ◽

A. Ripoll ◽

N. Pérez ◽

A. S. H. Prévôt ◽

F. Canonaco ◽

...

Keyword(s):

Real Time ◽

Chemical Speciation ◽

Chemical Characterization ◽

Western Mediterranean ◽

Data Matrix ◽

Mass Spectral ◽

Submicron Aerosol ◽

Regional Background ◽

Multilinear Engine

Abstract. An Aerosol Chemical Speciation Monitor (ACSM, Aerodyne Research Inc.) was deployed at Montseny (MSY, 720 m a.s.l.) regional background site in the Western Mediterranean from June 2012 to July 2013 to measure real-time inorganic (nitrate, sulphate, ammonium and chloride) and organic submicron aerosol concentrations. Co-located measurements were also carried out including real-time submicron particulate matter (PM1) and black carbon (BC) concentrations, and off-line PM1 chemical analysis. This is one of the few studies that compare ACSM data with off-line PM1 measurements, avoiding the tail of the coarse mode included in the PM2.5 fraction. The ACSM + BC concentrations agreed with the PM1 measurements, and strong correlation was found between the concentrations of ACSM species and the off-line measurements, although some discrepancies remain unexplained. Results point to a current underestimation of the relative ionization efficiency (RIE) established for organic aerosol (OA), which should be revised in the future. The OA was the major component of submicron aerosol (53% of PM1), with a higher contribution in summer (58% of PM1) than in winter (45% of PM1). Source apportionment of OA was carried out by applying Positive Matrix Factorization (PMF) using the Multilinear Engine (ME-2) to the organic mass spectral data matrix. Three sources were identified in summer: hydrocarbon-like OA (HOA), low-volatile oxygenated OA (LV-OOA), and semi-volatile oxygenated OA (SV-OOA). The secondary OA (SOA, 4.7 μg m−3, sum of LV-OOA and SV-OOA) accounted for 85% of the total OA and its formation during daytime (mainly SV-OOA) was estimated to be 1.1 μg m−3. In winter, HOA was also identified (12% of OA), a contribution from biomass burning OA was included, and it was not possible to differentiate two different SOA factors but a single OOA factor was resolved. The OOA contribution represented the 60% of the total OA, with a degree of oxidation higher than both OOA summer factors. An intense wildfire episode was studied obtaining a region-specific BBOA profile.

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Chemical characterization of submicron regional background aerosols in the western Mediterranean using an Aerosol Chemical Speciation Monitor

Atmospheric Chemistry and Physics ◽

10.5194/acp-15-6379-2015 ◽

2015 ◽

Vol 15 (11) ◽

pp. 6379-6391 ◽

Cited By ~ 31

Author(s):

M. C. Minguillón ◽

A. Ripoll ◽

N. Pérez ◽

A. S. H. Prévôt ◽

F. Canonaco ◽

...

Keyword(s):

Real Time ◽

Chemical Speciation ◽

Chemical Characterization ◽

Western Mediterranean ◽

Data Matrix ◽

Mass Spectral ◽

Submicron Aerosol ◽

Regional Background ◽

Multilinear Engine

Abstract. An Aerosol Chemical Speciation Monitor (ACSM, Aerodyne Research Inc.) was deployed at the Montseny (MSY; 41° 46'46" N, 02° 21'29" E, 720 m a.s.l.) regional background site in the western Mediterranean, Spain, from June 2012 to July 2013 to measure real-time inorganic (nitrate, sulfate, ammonium and chloride) and organic submicron aerosol concentrations. Co-located measurements, including real-time submicron particulate matter (PM1) and black carbon (BC) concentrations, and off-line PM1 chemical analysis were also carried out. This is one of the few studies that compare ACSM data with off-line PM1 measurements, avoiding the tail of the coarse mode included in the PM2.5 fraction. The ACSM + BC concentrations agreed with the PM1 measurements, and a strong correlation was found between the concentrations of ACSM species and the off-line measurements, although some discrepancies remain unexplained. Results point to a current underestimation of the relative ionization efficiency (RIE) established for organic aerosol (OA), which should be revised in the future. The OA was the major component of submicron aerosol (53% of PM1), with a higher contribution in summer (58% of PM1) than in winter (45% of PM1). Source apportionment of OA was carried out by applying positive matrix factorization (PMF), using the multilinear engine (ME-2) to the organic mass spectral data matrix. Three sources were identified in summer: hydrocarbon-like OA (HOA), low-volatile oxygenated OA (LV-OOA), and semi-volatile oxygenated OA (SV-OOA). The secondary OA (SOA; 4.8 μg m−3, sum of LV-OOA and SV-OOA) accounted for 85% of the total OA, and its formation during daytime (mainly SV-OOA) was estimated to be 1.1 μg m−3. In winter, HOA was also identified (12% of OA), a contribution from biomass burning OA (BBOA) was included and it was not possible to differentiate between two different SOA factors, but a single oxygenated OA (OOA) factor was resolved. The OOA contribution represented 60% of the total OA, with a degree of oxidation higher than both OOA summer factors. An intense wildfire episode was studied, obtaining a region-specific BBOA profile.

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