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Title: Individual Particle Analysis of Ambient PM 2.5 Using Advanced Electron Microscopy Techniques

Abstract

The overall goal of this project was to demonstrate a combination of advanced electron microscopy techniques that can be effectively used to identify and characterize individual particles and their sources. Specific techniques to be used include high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), STEM energy dispersive X-ray spectrometry (EDX), and energy-filtered TEM (EFTEM). A series of ambient PM{sub 2.5} samples were collected in communities in southwestern Detroit, MI (close to multiple combustion sources) and Steubenville, OH (close to several coal fired utility boilers). High-resolution TEM (HRTEM) -imaging showed a series of nano-metal particles including transition metals and elemental composition of individual particles in detail. Submicron and nano-particles with Al, Fe, Ti, Ca, U, V, Cr, Si, Ba, Mn, Ni, K and S were observed and characterized from the samples. Among the identified nano-particles, combinations of Al, Fe, Si, Ca and Ti nano-particles embedded in carbonaceous particles were observed most frequently. These particles showed very similar characteristics of ultrafine coal fly ash particles that were previously reported. By utilizing HAADF-STEM, STEM-EDX, and EF-TEM, this investigation was able to gain information on the size, morphology, structure, and elemental composition of individual nano-particles collected in Detroit and Steubenville. The results showedmore » that the contributions of local combustion sources - including coal fired utilities - to ultrafine particle levels were significant. Although this combination of advanced electron microscopy techniques by itself can not identify source categories, these techniques can be utilized as complementary analytical tools that are capable of providing detailed information on individual particles.« less

Authors:
;
Publication Date:
Research Org.:
University Of Michigan Systems
Sponsoring Org.:
USDOE
OSTI Identifier:
920187
DOE Contract Number:
FG26-05NT42542
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; BOILERS; COAL; COMBUSTION; COMMUNITIES; ELECTRON MICROSCOPY; FLY ASH; MORPHOLOGY; TRANSITION ELEMENTS; TRANSMISSION ELECTRON MICROSCOPY; X-RAY SPECTROSCOPY

Citation Formats

Gerald J. Keeler, and Masako Morishita. Individual Particle Analysis of Ambient PM 2.5 Using Advanced Electron Microscopy Techniques. United States: N. p., 2006. Web. doi:10.2172/920187.
Gerald J. Keeler, & Masako Morishita. Individual Particle Analysis of Ambient PM 2.5 Using Advanced Electron Microscopy Techniques. United States. doi:10.2172/920187.
Gerald J. Keeler, and Masako Morishita. Sun . "Individual Particle Analysis of Ambient PM 2.5 Using Advanced Electron Microscopy Techniques". United States. doi:10.2172/920187. https://www.osti.gov/servlets/purl/920187.
@article{osti_920187,
title = {Individual Particle Analysis of Ambient PM 2.5 Using Advanced Electron Microscopy Techniques},
author = {Gerald J. Keeler and Masako Morishita},
abstractNote = {The overall goal of this project was to demonstrate a combination of advanced electron microscopy techniques that can be effectively used to identify and characterize individual particles and their sources. Specific techniques to be used include high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), STEM energy dispersive X-ray spectrometry (EDX), and energy-filtered TEM (EFTEM). A series of ambient PM{sub 2.5} samples were collected in communities in southwestern Detroit, MI (close to multiple combustion sources) and Steubenville, OH (close to several coal fired utility boilers). High-resolution TEM (HRTEM) -imaging showed a series of nano-metal particles including transition metals and elemental composition of individual particles in detail. Submicron and nano-particles with Al, Fe, Ti, Ca, U, V, Cr, Si, Ba, Mn, Ni, K and S were observed and characterized from the samples. Among the identified nano-particles, combinations of Al, Fe, Si, Ca and Ti nano-particles embedded in carbonaceous particles were observed most frequently. These particles showed very similar characteristics of ultrafine coal fly ash particles that were previously reported. By utilizing HAADF-STEM, STEM-EDX, and EF-TEM, this investigation was able to gain information on the size, morphology, structure, and elemental composition of individual nano-particles collected in Detroit and Steubenville. The results showed that the contributions of local combustion sources - including coal fired utilities - to ultrafine particle levels were significant. Although this combination of advanced electron microscopy techniques by itself can not identify source categories, these techniques can be utilized as complementary analytical tools that are capable of providing detailed information on individual particles.},
doi = {10.2172/920187},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Dec 31 00:00:00 EST 2006},
month = {Sun Dec 31 00:00:00 EST 2006}
}

Technical Report:

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