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MVA Attendee: Richard S. Brown

Dates: August 3 – August 7, 2014
Location: Harford, CT

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MVA Attendee: Tim Vander Wood, Ph.D.

Dates: August 19 – August 21, 2014
Location: Baltimore, MD

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Presenting a poster on “Microscopical Methods in Particulate Matter Sizing and Compositional Analysis”

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MVA Attendees: Mary Miller and *Rich Brown

Date: Sep 28 – Oct 03, 2014
Location: Reno-Tahoe, Nevada

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*Rich Brown is Presenting:

Complimentary Techniques of Micro-Spectroscopy and Micro-Spectrometry in Industrial Forensic Investigations

Industrial Forensic investigations involve quality control issues that affect product quality, consumer safety and manufacturing costs. Foreign material appearing in a product during manufacture or after manufacture generates questions about the source of the material. The investigation, when initiated by the manufacturer, attempts to track raw materials, machinery, contact surfaces and the manufacturing environment to determine any source(s) of the foreign material. Small particles, one millimeter or less, discovered during the investigation are difficult to characterize using bulk analysis or non-microscopical methods. During this type of investigation preliminary data is used to determine the analysis work flow. The type of particle determines what type of testing is performed. Preliminary examination using low power stereomicroscopes, fluorescence, reflected brightfield, reflected darkfield and oblique illumination are used to determine how many types of particles are present, if the particles can be sub-sampled for multiple analyses to occur simultaneously and what type of testing will give the most information in the least amount of time. In this laboratory, particles are prepared for scanning electron microscopy-energy dispersive x-ray spectrometry (SEM-EDS) by placing them on a beryllium substrate. SEM-EDS is performed using high vacuum conditions if the particles are not prone to charging in the electron beam. Low vacuum analysis is performed when the particles are prone to charging or otherwise unstable. The particle, if an organic phase is suspected, is next analyzed by either Fourier transform infrared microspectroscopy (FTIR) and/or Confocal Raman microspectroscopy (CRM). Micro-extractions and examination of pyrolyzates may be necessary for polymers that are opaque or that are heavily loaded with inorganic fillers. A sub-sample of the particle, if it is transparent is obtained for examination of its optical properties by polarized light microscopy (PLM). At this point, the particle will be well characterized and sufficient information is available to determine suspected sources of the contamination. Additional work may be necessary if the particle contains multiple types of inorganic fillers, multiple coatings or if more than one particle type is present. Work done in this laboratory will be presented demonstrating the application of this analysis procedure and the practical limitations observed.