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Oil-matching by using a simple vector model for fluorescence spectra
T J Killeen1, D Eastwood, M S Hendrick
1Department of Statistics, University of Connecticut, Storrs, CT 06268, U.S.A.
Talanta
|January 1, 1981
Summary
This study introduces a vector model using angular distance to compare weathered oil fluorescence spectra. This method aids forensic oil identification by finding the best spectral match for oil spill samples.
Area of Science:
- Analytical Chemistry
- Forensic Science
Background:
- Fluorescence spectroscopy is crucial for analyzing oil composition.
- Weathering alters oil spectra, complicating identification.
- Existing methods may lack precision in comparing weathered oil spectra.
Purpose of the Study:
- To develop a novel vector model for comparing weathered oil fluorescence spectra.
- To apply this model for accurate forensic identification of oil spill sources.
- To enhance the precision of oil spill sample matching.
Main Methods:
- Representing digitized fluorescence spectra as vectors in n-dimensional space.
- Utilizing angular distance in n-space as a parameter for spectral comparison.
- Projecting oil-spill spectrum vectors onto a hyperlane defined by unweathered and laboratory-weathered oil spectra.
Main Results:
- The vector model effectively quantifies spectral differences using angular distance.
- The 'best fit' vector with minimal angular deviation was identified for oil spill samples.
- Successful application demonstrated in forensic oil identification scenarios.
Conclusions:
- The developed vector model provides a robust method for comparing weathered oil fluorescence spectra.
- Angular distance in n-space is a valuable parameter for forensic oil identification.
- This approach improves the accuracy of matching oil spill samples to potential sources.
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