Related Experiment Video
Updated: May 29, 2026
09:40
A Scanning Electron Microscopy-Compatible Optical Imaging Method for Mesoscopic All-Cell Brain Mapping
Published on: February 20, 2026
Analysis and discrimination of electrical tapes: part II. Backings
Andria H Mehltretter1, Maureen J Bradley, Diana M Wright
1Laboratory Division, Federal Bureau of Investigation, 2501 Investigation Parkway, Quantico, VA 22135, USA. andria.mehltretter@ic.fbi.gov
Journal of Forensic Sciences
|September 3, 2011
Summary
Forensic analysis of electrical tape backings using multiple techniques like FTIR and Py-GC/MS can effectively distinguish between samples. Combining these methods offers high discrimination rates for tape backing identification.
Area of Science:
- Forensic Science
- Materials Science
- Analytical Chemistry
Background:
- Electrical tapes are common in various settings, including crime scenes.
- Characterizing tape backings is crucial for forensic investigations.
- Previous studies focused on adhesive analysis, leaving backing characterization less explored.
Purpose of the Study:
- To evaluate chemical components of electrical tape backings.
- To assess the discriminatory power of individual analytical techniques.
- To determine the combined effectiveness of techniques for sample distinction.
Main Methods:
- Stereomicroscopy and physical measurements (surface features, width, thickness).
- Fourier transform infrared spectroscopy (FTIR) with a microscope accessory.
- Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS).
- Scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS).
Main Results:
- Individual techniques showed varying discrimination capabilities: Stereomicroscopy (c. 64%), FTIR (c. 83%), Py-GC/MS (c. 81%), SEM/EDS (c. 87%).
- A combination of these analytical methods achieved 94% discrimination of tape backings.
- Integrating backing analysis with prior adhesive data yielded an overall discrimination of nearly 96%.
Conclusions:
- Multiple analytical techniques provide robust discrimination of electrical tape backings.
- Combined analysis of tape backings and adhesives offers superior forensic identification.
- This comprehensive approach enhances the evidential value of electrical tape analysis.
Related Concept Videos
01:12Taping Over Different Ground Profiles
Taping over varying ground profiles requires careful adaptation to achieve accurate measurements. On smooth, level ground with minimal vegetation, the tape can rest directly on the ground. Here, the taping team, typically consisting of a head and a rear tapeman, coordinates their positions with clear communication. The rear tapeman holds the tape at the starting point and guides the head tapeman toward a range pole placed beyond the endpoint, using hand or voice signals to ensure alignment.On...
01:18Distance Measurements by Taping
Tapes are essential in surveying for accurate, durable, and short-distance measurements. Made from lightweight, nylon-coated steel, they offer flexibility and strength for rugged outdoor use. The nylon coating protects against rust and wear, extending the tape's life. Standard lengths, around 30 meters, are marked in meters and millimeters for precision.Surveyors select tapes based on site conditions and accuracy needs. Lightweight, nylon-coated tapes are commonly used for ease of handling and...
01:18Errors in Taping
Errors in taping arise from multiple factors that can significantly impact measurement accuracy in surveying. Misalignment of the tape, often due to human error, is one primary source. A skilled rear tapeman, using a telescope, can help correct alignment by guiding the head tapeman; however, human limitations still lead to small inaccuracies. These errors may include misplacement of pins or inaccurate tape readings due to common visual confusions, such as mistaking a six for a nine. Such...
01:23Insulation Coordination
Insulation coordination is the process of matching electric equipment's insulation strength with protective device characteristics to protect the equipment against expected overvoltages. This selection is based on engineering judgment and cost. Equipment can generally withstand short-duration high transient overvoltages, but repeated tests with identical waveforms can yield inconsistent results. As a result, standard impulse voltage waveforms are used for testing, defined by specific times for...
01:24Bode Plots Construction
The Bode plot is an essential tool in control system analysis, mapping the frequency response of a system through a magnitude plot and a phase plot, both against a logarithmic frequency axis. To construct a Bode plot, consider the transfer function H(ω):
01:25Resistance and Conductance
A conductor's DC resistance at a given temperature is influenced by its resistivity, length, and cross-sectional area. Resistivity is an inherent property of the conductor material, with annealed copper serving as the international standard for measurement. For instance, the resistivity of hard-drawn aluminum at 20 degrees Celsius is 61% of the standard conductivity of annealed copper.
Various factors impact the resistance of a conductor. Spiraling in stranded conductors increases their length...
Various factors impact the resistance of a conductor. Spiraling in stranded conductors increases their length...