Close-Range and Standoff Detection and Identification of Liquid Explosives by Means of Raman Spectroscopy

Surface-enhanced Raman spectroscopy (SERS) is a very promising analytical technique for the detection and identification of trace amounts of analytes. Among the many substrates used in SERS of great interest are nanostructures fabricated using physical methods, such as semicontinuous metal films obtained via electron beam physical vapor deposition. In these studies, we investigate the influence of morphology of semicontinuous silver films on their SERS properties. The morphologies studied ranged from isolated particles through percolated films to almost continuous films. We found that films below the percolation threshold (transition from dielectric-like to metal-like) made of isolated silver structures provided the largest SERS enhancement of 4-aminothiophenol (4-ATP) analyte signals. The substrate closest to the percolation threshold has the SERS signal about four times lower than the highest signal sample.

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Detection of Nitro-aromatic Compound in Soil and Sand using Time Gated Raman Spectroscopy

Defence Science Journal ◽

10.14429/dsj.67.10290 ◽

2017 ◽

Vol 67 (5) ◽

pp. 588 ◽

Cited By ~ 2

Author(s):

Kamal Kumar Gulati ◽

Vijayeta Gambhir ◽

M. N. Reddy

Keyword(s):

Raman Spectroscopy ◽

Benzoic Acid ◽

Signal To Noise Ratio ◽

Terrorist Attack ◽

Laser Pulses ◽

High Background ◽

Detection And Identification ◽

Set Up ◽

Detection Of Explosives ◽

Nitro Aromatic

<p>Laser based time-gated Raman Spectroscopy experiments for detection and identification of nitro-aromatic sample which premixed with soil and sand in different concentrations are conducted. A back-scattered stand-off Raman spectroscopy set-up using a frequency double Nd:YAG pulsed laser (532 nm, 8 ns, 10 Hz) was employed to evaluate samples made up of standard nitro- aromatic compounds, p-nitro Benzoic acid (PNBA) premixed with soil and sand at different concentrations. A sensitive ICCD detector was used to capture the weak Raman signals buried in high background noise at optimised experiments parameters like laser pulse energy, ICCD gate width, background subtraction, number of laser pulses averaging etc. p- nitro benzoic acid up to 5 per cent (v/v) concentration in sand with appreciable signal to noise ratio has been detected. This feasibility study also becomes relevant to evaluate the remnants for post-blast detection of explosives in terrorist attack as most of the explosives used in such attacks contain nitro-aromatic based high energetic explosives.</p>

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Standoff detection of trace amounts of solids by nonlinear Raman spectroscopy using shaped femtosecond pulses

Applied Physics Letters ◽

10.1063/1.2918014 ◽

2008 ◽

Vol 92 (17) ◽

pp. 171116 ◽

Cited By ~ 72

Author(s):

O. Katz ◽

A. Natan ◽

Y. Silberberg ◽

S. Rosenwaks

Keyword(s):

Raman Spectroscopy ◽

Femtosecond Pulses ◽

Standoff Detection

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Utilization of advanced clutter suppression algorithms for improved standoff detection and identification of radionuclide threats

10.1117/12.2049831 ◽

2014 ◽

Cited By ~ 1

Author(s):

Bogdan R. Cosofret ◽

Kirill Shokhirev ◽

Phil Mulhall ◽

David Payne ◽

Bernard Harris

Keyword(s):

Clutter Suppression ◽

Standoff Detection ◽

Detection And Identification

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Detection and identification of cancerous murine fibroblasts, transformed by murine sarcoma virus in culture, using Raman spectroscopy and advanced statistical methods

Biochimica et Biophysica Acta (BBA) - General Subjects ◽

10.1016/j.bbagen.2012.11.023 ◽

2013 ◽

Vol 1830 (3) ◽

pp. 2720-2727 ◽

Cited By ~ 25

Author(s):

A. Salman ◽

E. Shufan ◽

L. Zeiri ◽

M. Huleihel

Keyword(s):

Raman Spectroscopy ◽

Statistical Methods ◽

Detection And Identification ◽

Murine Fibroblasts ◽

Murine Sarcoma Virus ◽

Sarcoma Virus ◽

Murine Sarcoma

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A Fast Approximation for Adaptive Wavelength Selection for Infrared Chemical Sensors

10.26434/chemrxiv.7286243 ◽

2018 ◽

Author(s):

Mark Chilenski ◽

Cara Murphy ◽

Gil Raz

Keyword(s):

Synthetic Data ◽

Optical Power ◽

Laser Wavelength ◽

Information Theoretic ◽

Standoff Detection ◽

Detection And Identification ◽

Sensor Control ◽

Selection For ◽

Trace Chemicals ◽

Selection Of

<p>Active mid-infrared spectroscopy with tunable lasers is a leading technology for standoff detection and identification of trace chemicals. Information-theoretic optimal selection of the laser wavelength offers the promise of increased detection confidence at lower abundances and with fewer wavelengths. Reducing the number of wavelengths required enables faster detections and lowers sensor power consumption while keeping the optical power under eye safety limits. This paper presents an approximation to the mutual information which operates ~40000x faster than traditional techniques, thereby making near-optimal real-time sensor control computationally feasible. Application of this technique to synthetic data suggests it can reduce the number of wavelengths needed by a factor of two relative to an evenly-spaced grid, with even higher gains for chemicals with weak signatures.</p>

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Raman Spectroscopic and Advanced Signal Processing analyses for Real Time Standoff Detection and Identification of Explosives

10.21203/rs.3.rs-426964/v1 ◽

2021 ◽

Author(s):

Adel Abdallah ◽

Alaaeldin Mahmoud ◽

Mohamed Mokhtar ◽

Aiman Mousa ◽

Yahia Elbashar ◽

...

Keyword(s):

Raman Spectroscopy ◽

Signal Processing ◽

Real Time ◽

Laser Raman Spectroscopy ◽

Identification System ◽

Second Phase ◽

Accurate Identification ◽

Laser Raman ◽

Detection And Identification ◽

Two Phases

Abstract Laser Raman spectroscopy is a powerful instrument commonly used for detection of bulk and trace amounts of explosives. The work carried out in this paper is divided into two phases; the first phase is to propose a real time standoff explosive detection and identification system based on Raman spectroscopy that can be deployed in static checkpoints. The measurement is performed for samples placed in contact and at distances up to 1 meter in ambient light conditions. The second phase is to propose a novel sophisticated signal processing and pattern recognition techniques for accurate identification and classification of the investigated materials.

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