PMID- 22568856
OWN - NLM
STAT- MEDLINE
DCOM- 20120917
LR  - 20120608
IS  - 1520-5851 (Electronic)
IS  - 0013-936X (Linking)
VI  - 46
IP  - 11
DP  - 2012 Jun 5
TI  - Comparison of methods for online measurement of diesel particulate matter.
PG  - 6127-33
LID - 10.1021/es3003537 [doi]
AB  - Gravimetric analysis is the regulatory method for diesel particulate mass 
      measurement. Because of issues such as adsorption/volatilization artifacts, it 
      faces obstacles in measuring ultra low level emissions from modern diesel 
      engines. Alternative methods of suspended particle mass measurement have been 
      developed that show improvements in time resolution, sensitivity, and accuracy. 
      Three size-resolved methods were considered here. Two methods rely on converting 
      number size distributions obtained using a scanning mobility particle sizer 
      (SMPS). Conversion techniques were based on effective density measurements and 
      the Lall-Friedlander aggregate model. The third method employs the Universal 
      Nanoparticle Analyzer (UNPA) to measure the aggregate size distribution from 
      which mass is calculated. Results were compared with mass concentrations obtained 
      using gravimetric analysis. The effective density conversion resulted in mass 
      concentrations that were highly correlated (R(2) >0.99) with filter mass. The 
      ratios to filter mass concentration were found to be 0.99 +/- 0.04, 0.45 +/- 0.03, 
      and 0.45 +/- 0.19 for the effective density conversion, the Lall-Friedlander 
      conversion, and the UNPA, respectively, for a wide range of engine operating 
      conditions. In addition, the diesel aerosol mass distributions measured by the 
      online techniques are in agreement to within 15-20% with respect to the mass 
      median diameter, while discrepancies were observed in the mass concentration.
FAU - Liu, Zhun
AU  - Liu Z
AD  - Department of Mechanical Engineering, University of Minnesota, Minneapolis, 
      Minnesota 55455, United States. liuxx776@umn.edu
FAU - Swanson, Jacob
AU  - Swanson J
FAU - Kittelson, David B
AU  - Kittelson DB
FAU - Pui, David Y H
AU  - Pui DY
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20120521
PL  - United States
TA  - Environ Sci Technol
JT  - Environmental science & technology
JID - 0213155
RN  - 0 (Gasoline)
RN  - 0 (Particulate Matter)
RN  - 0 (Soot)
SB  - IM
MH  - Adsorption
MH  - Artifacts
MH  - Catalysis
MH  - Environmental Monitoring/*methods
MH  - Filtration
MH  - Gasoline/*analysis
MH  - Microscopy, Electron, Transmission
MH  - Molecular Weight
MH  - *Online Systems
MH  - Particle Size
MH  - Particulate Matter/*analysis
MH  - Soot/analysis
EDAT- 2012/05/10 06:00
MHDA- 2012/09/18 06:00
CRDT- 2012/05/10 06:00
PHST- 2012/05/10 06:00 [entrez]
PHST- 2012/05/10 06:00 [pubmed]
PHST- 2012/09/18 06:00 [medline]
AID - 10.1021/es3003537 [doi]
PST - ppublish
SO  - Environ Sci Technol. 2012 Jun 5;46(11):6127-33. doi: 10.1021/es3003537. Epub 2012 
      May 21.