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An effective method for substance detection using the broad spectrum THz signal with a "terahertz nose".

Trofimov VA, Varentsova SA - Sensors (Basel) (2015)

Bottom Line: This pulse excites, for example, many vibrational or rotational energy levels of molecules simultaneously.Comparing the absorption and emission spectrum dynamics of a substance under analysis with the corresponding data for a standard substance, one can detect and identify the substance under real conditions taking into account the influence of packing material, water vapor and substance surface.For quality assessment of the standard substance detection in the signal under analysis, we propose time-dependent integral correlation criteria.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Computational Mathematics and Cybernetics, Lomonosov Moscow State University, Leninskiye Gory, Moscow 119992, Russia;. vatro@cs.msu.ru.

ABSTRACT
We propose an effective method for the detection and identification of dangerous substances by using the broadband THz pulse. This pulse excites, for example, many vibrational or rotational energy levels of molecules simultaneously. By analyzing the time-dependent spectrum of the THz pulse transmitted through or reflected from a substance, we follow the average response spectrum dynamics. Comparing the absorption and emission spectrum dynamics of a substance under analysis with the corresponding data for a standard substance, one can detect and identify the substance under real conditions taking into account the influence of packing material, water vapor and substance surface. For quality assessment of the standard substance detection in the signal under analysis, we propose time-dependent integral correlation criteria. Restrictions of usually used detection and identification methods, based on a comparison between the absorption frequencies of a substance under analysis and a standard substance, are demonstrated using a physical experiment with paper napkins.

No MeSH data available.


Related in: MedlinePlus

TDS transmission setup (a); Reflection stand-off setup (b).
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sensors-15-12103-f002: TDS transmission setup (a); Reflection stand-off setup (b).

Mentions: The measurements were carried out in real conditions with a temperature 18 °C and a relative humidity of about 50%–60%. The distance between the parabolic mirror and the object was about 3.5 m. For TDS measurements of PWM C4 and other explosives (RDX, HMX, PETN), the Teraview TPS 3000 unit was used in transmission (Figure 2a) and reflection (Figure 2b) mode.


An effective method for substance detection using the broad spectrum THz signal with a "terahertz nose".

Trofimov VA, Varentsova SA - Sensors (Basel) (2015)

TDS transmission setup (a); Reflection stand-off setup (b).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4507671&req=5

sensors-15-12103-f002: TDS transmission setup (a); Reflection stand-off setup (b).
Mentions: The measurements were carried out in real conditions with a temperature 18 °C and a relative humidity of about 50%–60%. The distance between the parabolic mirror and the object was about 3.5 m. For TDS measurements of PWM C4 and other explosives (RDX, HMX, PETN), the Teraview TPS 3000 unit was used in transmission (Figure 2a) and reflection (Figure 2b) mode.

Bottom Line: This pulse excites, for example, many vibrational or rotational energy levels of molecules simultaneously.Comparing the absorption and emission spectrum dynamics of a substance under analysis with the corresponding data for a standard substance, one can detect and identify the substance under real conditions taking into account the influence of packing material, water vapor and substance surface.For quality assessment of the standard substance detection in the signal under analysis, we propose time-dependent integral correlation criteria.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Computational Mathematics and Cybernetics, Lomonosov Moscow State University, Leninskiye Gory, Moscow 119992, Russia;. vatro@cs.msu.ru.

ABSTRACT
We propose an effective method for the detection and identification of dangerous substances by using the broadband THz pulse. This pulse excites, for example, many vibrational or rotational energy levels of molecules simultaneously. By analyzing the time-dependent spectrum of the THz pulse transmitted through or reflected from a substance, we follow the average response spectrum dynamics. Comparing the absorption and emission spectrum dynamics of a substance under analysis with the corresponding data for a standard substance, one can detect and identify the substance under real conditions taking into account the influence of packing material, water vapor and substance surface. For quality assessment of the standard substance detection in the signal under analysis, we propose time-dependent integral correlation criteria. Restrictions of usually used detection and identification methods, based on a comparison between the absorption frequencies of a substance under analysis and a standard substance, are demonstrated using a physical experiment with paper napkins.

No MeSH data available.


Related in: MedlinePlus