Week #4 Report

This week more samples are here to be analyzed! The ones specific I would like to share are some filter samples. The major difference of these samples from the samples I have analyzed before is that they are collected in a laboratory rather than on the field. The samples to be discussed are collected from the fumes emitted from a burning of Douglas fir in a controlled environment. Those laboratory samples are able to help us to understand the composition and behavior of aerosols coming from a single source (in this case, a biomass burning aerosol ). Such knowledge can play an important role in our analysis of ambient (field) aerosol samples.

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Week #3 Progress

More data analysis is happening this week. This time I derived quantitative information from our data set, i.e. I tried to figure out exactly how much organic and inorganic species exists in each sample. A quick way to do so is to perform integration on the high-resolution time series plot for the sample set. Let me take the following time series plot for CALE sample set as an example. Notice that the green trace represents the amount of organics detected by the mass spectrometer at that time. If we integrate through the time series for one injection, i.e. calculate the area under one peak, we are able to obtain the number for the amount of organics (Org) present in that one injection of sample. A program file was written for Igor to perform the calculation.

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Summary for the first 2 weeks of research experience

Welcome to the research! In this first 2 weeks, I mainly focused on investigating the AMS data set we collected during the last semester. The ambient aerosol samples examined were collected in Toronto and Lethbridge, Canada (named CADO and CALE, with a total of 51 sample sets), and were run in the AMS of NASA. As a preliminary data processing step, I paid more attention on qualitative information: 1) the amount of organic matter in each sample run, 2) the organic composition of the collected aerosol sample, 3) the degree of oxidation of organics in each sample.

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Abstract: Study on chemical compositions and sources of organic aerosols in urban areas

Aerosols are small liquid droplets or solid particles suspended in the atmosphere. They can be formed naturally in the atmosphere or produced from human activities. Several examples of these anthropogenic aerosols are haze, smoke, and particulate air pollutants. Such pollutants, as a major part of urban air pollution, can lead to approximately 3 million premature deaths worldwide per year. Understanding the sources and compositions of these aerosol particles can be crucial for epidemiological studies and risk assessment on long-term human-exposure to urban air pollution. In this project, I will be investigating organic aerosols from locations around the world to study 1) the major chemical compositions of urban organic aerosols, 2) the molecular composition/structure for some organic aerosol components of interest (e.g. organic nitrogen species), and 3) possible sources of these aerosols. Several analytical techniques will be involved in this project, such as aerosol mass spectromety (AMS) and ultra-high resolution mass spectrometry (UHR-MS). This will be the first look at organic aerosols with these techniques in many of the cities. The obtained data and results will hopefully become a valuable resource for further research on atmospheric aerosols in these regions, and can be applied in health effects research through the understanding of the health-damaging effects of the particulate matter in urban air.124801351_origScreen-Shot-2015-05-08-at-14.56.37