Omar El Hajj, Ph.D. in Engineering, Research Scientist/R&D/Post-Doctoral Position

OMAR EL HAJJ, University of Georgia

     Abstract Number: 614
     Working Group: Meet the Job Seekers

Abstract
My current research focuses on the physicochemical properties of combustion carbonaceous aerosols. In my research, I perform controlled combustion experiments to generate aerosols and measure their physical properties (size distribution and optical properties), in addition to collecting filter samples for offline chemical analysis using different mass spectrometry techniques (LDI, ESI-MS, nano-DESI-MS). My research led to the discovery of new aerosols that form under low temperature combustion (LTC) conditions with two-stage ignition fuels. The results were published in the journal Fuel.

Currently, we are exploring the effect of blending octane boosters on aerosol formation in LTC of two-stage ignition fuels, including biofuels additves. Part of my research also includes investigating the properties and cytoxicity of brown carbon (BrC) aerosols generated from biomass combustion, where I contributed in building a biomass gravimetric micro-feeder to perform controlled biomass combustion. Moreover, during November of last year I participated in a research campaign at the National Transportation Research Center (NTRC) at Oak Ridge national lab. The campaign’s objective was to study the effects of engine operation modes and fuels on the properties of the exhaust aerosols. I measured light absorption data of the aerosols emitted at each condition using a photoacoustic spectrometer and combined it with size distribution data to obtain optical properties.

Prior to my PhD research, I worked on sampling aerosols and gas phase emissions from electronic cigarettes (ECIGs). This was part of my masters thesis research and was funded by the FDA in order to regulate ECIGs in the US. I developed an experimental method that would predict operating conditions that release volatile carbonyl compound based on ECIG design features and user puffing behavior.

I am seeking a research scientist or postdoc position where I can utilize my technical skills in aerosol sampling, collection, analysis, and instrumentation in laboratory or field settings.