Environmental factors affecting rapid shear in fibers from the passage of a bullet.

In forensic casework, examination of garment damage can provide insight into the mechanism of the specific cause of fiber failure. Different methods of damage impart differing physical characteristics on individual fibers. These alterations are determined by a multitude of factors, among them increased temperature of affected fibers.

A More Efficient Method for Synthetic Textile Fiber Analysis Using Polarized Light Microscopy.

The efficiency of conventional polarized light microscopy (PLM) methods for analyzing synthetic fiber evidence analyses is improved. Historically, using PLM for fiber identification relied on measuring refractive index. This prior PLM technology is reliable, but it is not efficient.

The Evidentiary Significance of Automotive Paint from the Northeast: A Study of Red Paint.

This population study was conducted to assess the frequency of physical, microscopical, and chemical properties of automotive paint chips. Population studies of trace evidence provide valuable analytical data for criminalists to assess evidentiary significance. Two-hundred automotive paint chips were collected from auto body shops from the Northeastern United States.

Collecting Quality Infrared Spectra from Microscopic Samples of Suspicious Powders in a Sealed Cell.

The infrared (IR) microspectroscopical analysis of samples within a sealed-cell containing barium fluoride is a critical need when identifying toxic agents or suspicious powders of unidentified composition. The dispersive nature of barium fluoride is well understood and experimental conditions can be easily adjusted during reflection-absorption measurements to account for differences in focus between the visible and IR regions of the spectrum. In most instances, the ability to collect a viable spectrum is possible when using the sealed cell regardless of whether visible or IR focus is optimized.

Development and Applications of Portable Gas Chromatography-Mass Spectrometry for Emergency Responders, the Military, and Law-Enforcement Organizations.

Portable gas chromatography-mass spectrometry (GC-MS) systems are being deployed for field use, and are designed with this goal in mind. Performance characteristics of instruments that are successful in the field are different from those of equivalent technologies that are successful in a laboratory setting. These field-portable systems are extending the capabilities of the field user, providing investigative leads and confirmatory identifications in real time.

Characterization of multilayered glitter particles using synchrotron FT-IR microscopy.

Multilayered glitter particles were cut with a microtome into thin cross-sections and examined using an FT-IR microscope with a synchrotron infrared source. The high brightness of the synchrotron source enabled high-quality infrared spectra to be quickly obtained from individual layers in the glitter particle cross-section, providing additional chemical information that could increase the glitter particle's value as associative evidence in criminal cases.

Synchrotron infrared confocal microspectroscopical detection of heterogeneity within chemically modified single starch granules.

This reports the first detection of chemical heterogeneity in octenyl succinic anhydride modified single starch granules using a Fourier transform infrared (FT-IR) microspectroscopical technique that combines diffraction-limited infrared microspectroscopy with a step size that is less than the mask projected spot size focused on the plane of the sample. The high spatial resolution was achieved with the combination of the application of a synchrotron infrared source and the confocal image plane masking system of the double-pass single-mask Continuum infrared microscope. Starch from grains such as corn and wheat exists in granules.

A novel approach to the examination of soil evidence: mineral identification using infrared microprobe analysis.

Identification of minerals using the infrared microprobe with a diamond internal reflection objective is a rapid and reliable method for forensic soil examinations. Ninety-six mineral varieties were analyzed, and 77 were differentiated by their attenuated total reflection (ATR) spectra. Mineral grains may be mounted in oil for conventional polarized light microscope characterization and their ATR spectrum obtained with little or no interference by the liquid.

Remembering Walter C. McCrone--scientist, mentor, leader and friend.

Walter C. McCrone (1916-2002) was a special person. While books, journals and ledgers record over 400 of his technical contributions, his true legacy is his inspiration and leadership.