ThOC



Code: ThOC Time Slot/Poster Number: 10:30 - 11:00 am Session: Forensics/Geoscience/Environmental/Astrobiology

On the contribution of Raman spectroscopy to forensic science
Patrick Buzzini1; Genevieve Massonnet2
1West Virginia University, Morgantown, WV; 2University of Lausanne, Lausanne, Switzerland

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Summary
Raman spectroscopy has only recently sparked interest from forensic laboratories. The Raman technique has demonstrated important advantages such as its non-destructive nature, its fast analysis time, and especially the possibility of performing microscopical in situ analyses. In forensic applications, it is a versatile technique that covers a wide spectrum of substances such as trace evidence, illicit drugs and inks. An overview of the recent developments of Raman spectroscopy in forensic science will be discussed. Also, the requirements for an analytical technique for the examination of physical evidence will be described. Examples of casework will be depicted.

Code: ThOC Time Slot/Poster Number: 11:00 - 11:30 am Session: Forensics/Geoscience/Environmental/Astrobiology

Excited- and Ground-State Reaction Dynamics of Nitrosyl Chloride in Solution
Phil Reid
University of Washington, Seattle, WA

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Summary
The excited- and ground-state reaction dynamics of nitrosyl chloride (ClNO) in solution are investigated. Resonance Raman Intensity Analysis (RRIA) is used to provide a mode-specific picture of the excited-state relaxation dynamics. This evolution is dominated by motion along the Cl-N stretch and bend coordinates. Ground-state photoproduct formation dynamics are studied using time-resolved infrared absorption spectroscopy. The quantum yield for geminate recombination of primary Cl and NO photofragments to reform ground-state ClNO is determined to be 0.5. In solution, geminate recombination results in a reduction in the quantum yield for Cl production relative to the gas phase.

Code: ThOC Time Slot/Poster Number: 11:30 am - 12:00 pm Session: Forensics/Geoscience/Environmental/Astrobiology

Discriminant Analysis of Raman Spectra for Body Fluid Identification for Forensic Purposes
Vitali Sikirzhytski; Kelly Virkler; Igor Lednev
Department of Chemistry, University at Albany, SUN, Albany, NY

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Summary
We elaborate a novel nondestructive, confirmatory method for the fast identification of body fluid traces on a crime scene using near IR Raman microspectroscopy. To date, an unknown biological stain has been identified via series of destructive chemical and biochemical tests. An efficient, on-field, nondestructive, and confirmatory method for body fluid identification is long awaited by the forensic community. Discriminant analysis (SIMCA, LDA and PLS-DA) allowed for discriminating semen, blood and saliva traces with over 99% confidence under laboratory conditions. The ability to make this identification on-site at a crime scene would be a major advance in the forensic analysis.

Code: ThOC Time Slot/Poster Number: 12:00 - 12:20 pm Session: Forensics/Geoscience/Environmental/Astrobiology

Time-Resolved Remote Raman Spectroscopy for Characterizing Surface Mineralogy on Planetary Surfaces
Shiv Sharma; Anupam Misra
University of Hawaii, Honolulu, HI

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Summary
Advancements in lasers, spectrographs and holographic optical components have led to the development of time-resolved (TR) remote Raman systems for planetary exploration from a lander or a rover. A TR remote Raman spectrometer capable of detecting minerals, inorganic and organic chemicals, and biogenic materials during daytime and nighttimes to radial distances in the range 10 to 125 m has been tested under terrestrial environments. In this contribution we discuss applications of a compact TR remote Raman system for detecting minerals to 50 m radial range under the Earth environment, and under simulated environments for Venus and Mars.

Code: ThOC Time Slot/Poster Number: 12:20 - 12:40 pm Session: Forensics/Geoscience/Environmental/Astrobiology

Detection of High Energy Materials at Safe Distances
Rick Cox; Brad Williams; Matt Russell; Bryan Ray
DeltaNu, Laramie, WY

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Summary
We will demonstrate results from portable stand-off Raman systems for identification of high energy materials. The first system is a handheld 785 based system with distance capabilities from 0.3 to 3 meters. The second system is a larger tripod mounted system based on 1064 nm laser excitation that measures distances from 3 to 10 meters.