1. X-ray Diffraction Study Of New York City Aerosols Particles Junior Nkrumah Summer Program of 2007 CCNY Dr. Jeff Steiner Ph.D. Student Nick Steiner Dr. Liz Rudolph Abstract Introduction The study of Aerosols in New York City has been one of the major studies in the New York State. Aerosols are suspensions of small solid or liquid particles. Aerosols can be dust particles. These dust particles may be dangerous to human health. Dust particles can cause contamination and can effect many parts of our earth system. In 2000-2003 scientists from different locations measured gaseous aerosols HCL, HNO 3 and NH 3 in the Bronx and Manhattan. When the measurements were collected and tested, large concentrations were observed in both boroughs. Scientists discovered that chemicals that were collected originated in wind parcels from from south to west of New York. City Materials and Methods/sampling X-ray diffraction is used to identify compounds in unknowns by recognizing structures. When a sample is being analyzed by X-ray diffraction, the beam (x-ray) hits the sample. If the sample is a solid, the x-ray will be diffracted and give us unique shapes and pattern. E bam (Met-one E bam) is a portable real-time beta gauge. E bam is the most reliable machine ever built. Its ability to collects aerosol particles is very interesting. Diagram of (XRD) http://images.google.com/image In the XRD there is a x-ray (beam) that hits the aerosols. Diffracted rays are directed to and counted by the spectrometer. Data/Results Pink lines represents 6-27-07 a Blue lines represents 6-26-07 a The height of the peaks are reflection of how much material and minerals that are presented. 2-theta shows the angle of the X- ray(XRD) to give us the structure of the samples Experimental Setup Met-one E bam was set up on the roof of the administration building. Air samples were collected for 24 hours. Particles that were collected on the silica ribbon filter paper are then taken to the lab for analysis. The Aerosols on the Filter paper were placed in a petri dish for storage. The sample, was then removed and placed on a (XRD) background free sample holder. The slide is then placed in the XRD and examined with a program evaluating 2-theta angles from 15 to 55 degrees lasting for about 50 minutes. When samples are done, we then use the Philips computer program Identify, to find the compounds present. We are getting closer to identifying and classifying aerosols by composition based on the differences between diffractograms from day to day. We will be using X-Ray Fluorescence (XRF) to find and identify the metals in the aerosols samples We need to identify large scale changes and figure out how weather patterns affect the composition of aerosols. http://images.google.com/image Materials and Method analysis This research is the study of Aerosols in New York City. Aerosols particles can cause acid rain as well as cardiovascular and respiratory problems. Due to the increasing population and pollution in New York City aerosol concentration is increasing. Some aerosols are produced naturally (pollen, spores) and others originate from burning fossil fuels, human activities and organic molecules. To determine aerosol concentration in NYC, samples are collected by using a system called, Met-One E Bam and determine the aerosol composition, we use X-ray diffraction, which is used to find compounds in the sample by recognizing the structure. Discussion/Conclusion These results are significant because they help the investigator to identify the particles. Also with these results the investigator will be able to figure out the origins of these particles. One interesting observation about these results is that even though the scans were taken on different days they have similar results. Sponsors National Aeronautics and Space Administration (NASA) NASA Goddard Space Flight Center (GSFC) NASA Goddard Institute for Space Studies (GISS) NASA New York City Research Initiative (NYCRI) Contributors Dr. Jeff Steiner- Professor Of Geochemistry City College Of New York. Dr. Elizabeth Rudolph- Professor Earth Science City College of New York. Ph.D. student Nick Steiner -City College of New York. Future work References www.outreach.phy.cam.ac.uk/camphy/xraydiffraction/xraydiff raction3 Mage, D., Ozolins,G., Peterson,.P Webster, A, Orthofer, R Vandeweerd, V.,Gwayne, M., 1996. Urban air pollution in megacitices of the world indarticles.com/p/articles/mi_m0HST/is_5_4/ai91913259 26k 1 -www.giss.nasa.gov/ dept.physics.upenn.edu/~ heiney/talks/hires/whatis.html