Esther Coz1,2, Gary Casuccio3, Traci L. Lersch3, Teresa Moreno2 and Begoña Artíñano1
5th DAURE Science MeetingBarcelona, May 26
DAURE Microscopy
1 Ciemat, Madrid2 IDAEA-CSIC, Barcelona
3 RJ Lee Inc., Pittsburgh (USA)
Methodology
Particle Collection
Scanning Electron MicroscopyEnergy
Dispersive X-ray Spectroscopy
Digital Image Analysis
Elemental Composition Morphology
Data Analysis
How?
Sampling Particle Collection
Low-Vol sampler Eight-stage cascade
impactor (Andersen)
Impactor Stage (cut-off size)Stage 1 2 3 4 5 6 7 8
D50 (m) 16 10 4.0 2.4 1.5 0.85 0.47 0.29
PM2.5 samples:
• Period: Feb 25 – 28
• Times: 7 am, 11 am, 5 pm and 8 am
• Intervals: 30 min – 2 hours
PM2.5: PC filters PM2.5-10: Aluminum substrates
No fiber filters
Sampling BCN site
0
20
40
60
80
100
120
140
2:00
8:00
14:0
0
20:0
0
2:00
8:00
14:0
0
20:0
0
2:00
8:00
14:0
0
20:0
0
2:00
8:00
14:0
0
20:0
0
2:00
8:00
14:0
0
20:0
0
02/24 02/25 02/26 02/27 02/28
PM-10 PM-2.5 PM-1.0
0
3000
6000
9000
12000
15000
18000
0:00
2:00
4:00
6:00
8:00
10:00
12:00
14:00
16:00
18:00
20:00
22:00
0:00
2:00
4:00
6:00
8:00
10:00
12:00
14:00
16:00
18:00
20:00
22:00
0:00
2:00
4:00
6:00
8:00
10:00
12:00
14:00
16:00
18:00
20:00
22:00
0:00
2:00
4:00
6:00
8:00
10:00
12:00
14:00
16:00
18:00
20:00
22:00
0:00
2:00
4:00
6:00
8:00
10:00
12:00
14:00
16:00
18:00
20:00
22:00
02/24 02/25 02/26 02/27 02/28
BC(ng/m3)
CSIC data
CSIC data
Sampling BCN site
• PM2.5 concentrations ~ 20-60 g·m-3
• Coarse to fine PM ratios: 0
10
20
30
40
50
60
16:12
18:12
20:12
22:12
0:12
2:12
4:12
6:12
8:12
10:12
13:22
15:22
17:22
19:22
21:22
23:22
1:22
3:22
5:22
7:22
9:22
11:22
13:22
15:22
17:22
19:22
21:22
23:22
1:22
3:22
5:22
7:22
9:22
11:22
14:40
16:40
18:40
20:40
22:39
0:45
2:44
4:45
6:45
8:44
10:45
12:45
18:40
20:40
22:40
23:54
SO4 NO3 NH4 Org Chl
Which complementary information does
electron microscopy give?
PSI data
Methodology Scanning Electron Microscopy
Electron Emission
Electromagneticlenses
X-raydetector
SEdetector
SEdetector
Signalconversion
Signalconversion
Pump
Scanningcoils
Sample
Methodology Scanning Electron Microscopy
Quantitative AnalysisQualitative Analysis
Personal SEM (Aspex Inc.)
Fully Computer Controlled SEM
(CCSEM) FEI Sirion 400Hitachi S5000
High Resolution SEM (HRSEM)
10-E4
Field
Shape Parameters
Dmin
DmaxSp1=Dp/Dmax
Sp2=Dmin/Dmax
AR=Dmax/D’min
Dp=(4/Area)1/2
DmaxDmin
Data Analysis
Particle by particle (>20,000): C, O, Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Zn, Ba, Pb
Minerals Heavy MetalOxides
Ammonium Sulfate(bisulfate)
Primary Biogenic Organic Aerosols
Carbonaceous & Nitrates
Silicates & Aluminosilicates
Calcium Carbonates
Sulfates
Non sulfate salts
Iron Oxides
Ti Oxides
…
Clustering
• Particle number, Volume and mass contribution
• Size distribution
• Associated quantitative morphology (circularity, convexity, elongation and
compactness)
Cluster by cluster:
Data Analysis
Aluminosilicates: Natural vs.
Industrial origin
Soot-like agglomerates: Fresh vs. Aged