Matthew P. Fraser, Ph.D.

Associate Professor
Department of Civil and Environmental Engineering
Rice University

Use of Optical Sensors of Studying Air Pollution in Houston - TexAQS 2006

In Houston, the presence of highly reactive alkenes in the emissions from petrochemical manufacturing results in the rapid formation of ground-level ozone and is one of the most pressing environmental problems facing the region. Laser based trace gas sensors provide an unprecedented ability to rapidly and accurately quantify trace gases important to urban air pollution including formaldehyde and ethylene.

Currently, we are involved in a coordinated study of ozone formation in southeastern Texas called TexAQS 2006. Our research team has deployed an mid-infrared optical sensor for quantification of gas-phase ethylene and formaldehyde, two trace gases vitally important in understanding ozone chemistry in Houston. The optical sensor uses interband cascade lasers (ICLs) to access the absorption features of formaldehyde at ~ 2807 cm-1 and ethylene at ~ 2997 cm-1. Using a 100 meter astigmatic Herriott multipass absorption cell, two TEC cooled MCT detectors, and a LN2 cryostat, we will measure the concentrations of both formaldehyde and ethylene with ppb precision. This talk will describe both the specific sensor system deployed as well as the general application of mid-infrared optical sensors for environmental sensing applications.
Thursday, September 7, 2006
3:00 p.m. - Duncan Hall 1049
Rice University

ECE Affiliates Meeting



Last modified: August 10, 2006