The Combustion Diagnostics and
Environmental Measurements Laboratory
|
|
The Combustion Diagnostics and Environmental Measurements Laboratory |
|
|
Laser-Induced Breakdown Spectroscopy (LIBS)
for Measurement of Ambient Particles
Here, we aim to understand the inorganic composition of ambient PM 2.5 in an urban atmosphere. Particulate matter smaller than 2.5 microns has been implicated in a variety of health effects. We would like to understand the composition / size relationship both for possible connection to health effects and also to develop source / receptor relationships for PM. In addition, we have recently demonstrated LIBS discrimination of various biological aerosols, focusing on the differentiation of anthrax simulant from other aerosols of biological origin, such as pollen. The ambient measurements project has been funded by the U.S. Department of Energy, through a subcontract with Carnegie Mellon University. Work described here has been performed as part of the Pittsburgh Air Quality Study, jointly funded by the U.S. DOE and EPA. In addition, baseline funding for the investigation of the aerosol / plasma interaction, which supports this work, is from the NSF Early CAREER Development Program . |
What is LIBS? In LIBS, a pulsed laser creates a microplasma that can be between 10,000 - 15,000 K. The plasma vaporizes particles and fragments molecules into atoms, thermally exciting electrons into excited states. As the plasma cools, the electrons relax, yielding familiar atomic emissions lines that can be used to quantify elemental mass concentrations. Recent publications / papers: Recent Results: Talk from the LIBS 2002 conference, Sept 26. Ambient particles talk from AAAR, Oct 2003 Bioaerosol discrimination talk from AAAR, Oct 2003
|
||
