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Narlagiri LM, Bharati M, Beeram R, Banerjee D, Soma VR. Recent trends in laser-based standoff detection of hazardous molecules. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2022.116645] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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2
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Major KJ, Sanghera JS, Farrell ME, Holthoff E, Pellegrino PM, Ewing KJ. Spectral Considerations for Standoff Infrared Detection of RDX on Reflective Aluminum. APPLIED SPECTROSCOPY 2022; 76:163-172. [PMID: 34643139 DOI: 10.1177/00037028211053865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
This paper examines infrared spectroscopic effects for the standoff detection of an explosive material, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), inkjet printed on an aluminum surface. Results of a spectroscopic study are described, using multiple optical setups. These setups were selected to explore how variations in the angles of incidence and collection from the surface of the material result in corresponding variations in the spectral signatures. The goal of these studies is to provide an understanding of these spectral changes since it affects standoff detection of hazardous materials on a reflective substrate. We demonstrate that variations in spectral effects are dependent on the relative surface concentration of the deposited RDX. We also show that it is reasonable to use spectroscopic data collected in a standard laboratory infrared spectrometer outfitted with a variable angle reflectometer set at 0° as reference spectra for data collected in a standoff configuration. These results are important to provide a systematic approach to understanding infrared (IR) spectra collection using standoff systems in the field, and to allow for comparison between such data, and data collected in the laboratory. Although the precise results are constrained to a specific material system (thin layers on a reflective substrate), the approach and general discussion provided are applicable to a broad range of IR standoff sensing techniques and applications.
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Affiliation(s)
- Kevin J Major
- Optical Sciences Division, US Naval Research Laboratory, Washington, DC, USA
| | | | - Mikella E Farrell
- United States Army Research Laboratory, RDRL-SEE-E, Adelphi, MD, USA
| | - Ellen Holthoff
- Office of the Deputy Assistant of the Army for Research and Technology, Arlington, VA, USA
| | - Paul M Pellegrino
- United States Army Research Laboratory, RDRL-SEE-E, Adelphi, MD, USA
| | - Kenneth J Ewing
- Optical Sciences Division, US Naval Research Laboratory, Washington, DC, USA
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3
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Carter JC, Paul PH, Ottaway JM, Haugen P, Manuel AM. Standoff Detection of Oil and Powder Mixtures at 12 Meters Using a Tunable Quantum Cascade Laser-Based System with a Close Focus Telescope and Uncooled Infrared Detector. APPLIED SPECTROSCOPY 2022; 76:19-27. [PMID: 34965744 DOI: 10.1177/00037028211060389] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
We have designed and demonstrated a quantum cascade laser (QCL) based standoff system that utilizes an uncooled mercury cadmium telluride (MCT) detector with lock-in signal processing for chemical identification at a distance of 12.5 meters in indoor ambient light conditions. In the system, a tunable quad-QCL operating (1 MHz) in quasi-continuous wave mode between 8.45 and 10.03 μm (∼1182 to 1000 cm-1) serves as the active mid-infrared source for remotely interrogating mineral, powder, and thin film oil samples including powder mixtures (6, 12.5, 25, and 50%) of crystalline quartz (SiO2) in KBr. Light as reflected from a given sample is collected using a 10-inch (25.4 cm) Dall Kirkham telescope and coupled with ZnSe optics to an uncooled MCT detector. The mixture dependence of the highly transparent KBr and strongly absorbing quartz was found to fit a modified version of the Schatz reflectance model for compacted powder mixtures. All reflectance spectra reported are relative to an Au-coated diffuse reflector. A NIST traceable polystyrene standard reflector was also used to determine the QCL wavelength tuning range and calibration.
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Affiliation(s)
- J Chance Carter
- 4578Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Phillip H Paul
- 4578Lawrence Livermore National Laboratory, Livermore, CA, USA
| | | | - Peter Haugen
- 4578Lawrence Livermore National Laboratory, Livermore, CA, USA
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Agranat AJ, Kabessa Y, Shemer B, Shpigel E, Schwartsglass O, Atamneh L, Uziel Y, Ejzenberg M, Mizrachi Y, Garcia Y, Perepelitsa G, Belkin S. An autonomous bioluminescent bacterial biosensor module for outdoor sensor networks, and its application for the detection of buried explosives. Biosens Bioelectron 2021; 185:113253. [PMID: 33930754 DOI: 10.1016/j.bios.2021.113253] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/26/2021] [Accepted: 04/12/2021] [Indexed: 11/19/2022]
Abstract
We describe a miniaturized field-deployable biosensor module, designed to function as an element in a sensor network for standoff monitoring and mapping of environmental hazards. The module harbors live bacterial sensor cells, genetically engineered to emit a bioluminescent signal in the presence of preselected target materials, which act as its core sensing elements. The module, which detects and processes the biological signal, composes a digital record that describes its findings, and can be transmitted to a remote receiver. The module is an autonomous self-contained unit that can function either as a standalone sensor, or as a node in a sensor network. The biosensor module can potentially be used for detecting any target material to which the sensor cells were engineered to respond. The module described herein was constructed to detect the presence of buried landmines underneath its footprint. The demonstrated detection sensitivity was 0.25 mg 2,4-dinitrotoluene per Kg soil.
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Affiliation(s)
- Aharon J Agranat
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Yossef Kabessa
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel.
| | - Benjamin Shemer
- Department of Plant & Environmental Sciences, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Etai Shpigel
- Department of Plant & Environmental Sciences, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Offer Schwartsglass
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Loay Atamneh
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Yonatan Uziel
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Meir Ejzenberg
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Yosef Mizrachi
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Yehudit Garcia
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Galina Perepelitsa
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Shimshon Belkin
- Department of Plant & Environmental Sciences, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
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Standoff pump-probe photothermal detection of hazardous chemicals. Sci Rep 2020; 10:15053. [PMID: 32929139 PMCID: PMC7490358 DOI: 10.1038/s41598-020-71937-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 07/01/2020] [Indexed: 11/17/2022] Open
Abstract
A novel pump-probe Photothermal methodology using Quartz Tuning Fork (QTF) detector has been demonstrated for the first time. A tunable mid-IR Quantum Cascade Laser (QCL) and a CW fixed wavelength visible laser have been used as the pump and probe beam respectively. The developed Photothermal (PT) technique is based on Quartz Tuning Fork (QTF) detector for the detection of hazardous/explosive molecules adsorbed on plastic surface and also in aerosols form. PT spectra of various trace molecules in the fingerprinting mid- infrared spectral band 7–9 µm from distance of 25 m have been recorded. The PT spectra of explosives RDX, TNT and Acetone have been recorded at very low quantities. Acetone is the precursor of explosive Tri-Acetone Tri-Phosphate (TATP). The experimentations using pump and probe lasers, exhibit detection sensitivity of less than 5 μg/cm2 for RDX, TNT powders and of ~ 200 nl quantity for Nitrobenzene (NB) and Acetone (in liquid form) adsorbed on surfaces, from a distance of ~ 25 m. The sensitivity of the same order achieved from a distance of 15 m by using only a mid-IR tunable pump laser coupled to QTF detector. Thus the pump-probe PT technique is more sensitive in comparison to single tunable QCL pump beam technique and it is better suited for standoff detection of hazardous chemicals for homeland security as well as for forensic applications.
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Standoff Chemical Detection Using Laser Absorption Spectroscopy: A Review. REMOTE SENSING 2020. [DOI: 10.3390/rs12172771] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Remote chemical detection in the atmosphere or some specific space has always been of great interest in many applications for environmental protection and safety. Laser absorption spectroscopy (LAS) is a highly desirable technology, benefiting from high measurement sensitivity, improved spectral selectivity or resolution, fast response and capability of good spatial resolution, multi-species and standoff detection with a non-cooperative target. Numerous LAS-based standoff detection techniques have seen rapid development recently and are reviewed herein, including differential absorption LiDAR, tunable laser absorption spectroscopy, laser photoacoustic spectroscopy, dual comb spectroscopy, laser heterodyne radiometry and active coherent laser absorption spectroscopy. An update of the current status of these various methods is presented, covering their principles, system compositions, features, developments and applications for standoff chemical detection over the last decade. In addition, a performance comparison together with the challenges and opportunities analysis is presented that describes the broad LAS-based techniques within the framework of remote sensing research and their directions of development for meeting potential practical use.
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Simin N, Park Y, Lee D, Thundat T, Kim S. Enhanced nanoplasmonic heating in standoff sensing of explosive residues with infrared reflection-absorption spectroscopy. OPTICS LETTERS 2020; 45:2144-2147. [PMID: 32287177 DOI: 10.1364/ol.387653] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 03/10/2020] [Indexed: 06/11/2023]
Abstract
Various standoff sensing techniques employing optical spectroscopy have been developed to address challenges in safely identifying trace amounts of explosives at a distance. A flexible anodic aluminum oxide (AAO) microcantilever and a high-power quantum cascade laser utilized as the infrared (IR) source are used for standoff IR reflection-absorption spectroscopy to detect explosive residues on a metal surface. Standoff sensing of trinitrotoluene (TNT) is demonstrated by exploiting the high thermomechanical sensitivity of a bimetallic AAO microcantilever. Moreover, sputtering gold onto the fabricated AAO nanowells generates a strong scattering and absorption of IR light in the wavelength range of 5.18 µm to 5.85 µm resulting in enhanced nanoplasmonic heating. Utilizing the IR absorption enhancement in this wavelength range, the plasmonic AAO cantilever could detect TNT molecules 7 times better than could the bimetallic AAO cantilever.
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Choi S, Jeong Y, Koh YJ, Lee JH, Nam H, Lee J. Analysis of Raman Spectral Characteristics of Chemical Warfare Agents by Using 248‐nm UV Raman Spectroscopy. B KOREAN CHEM SOC 2019. [DOI: 10.1002/bkcs.11679] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Sun‐Kyung Choi
- Agency for Defense Development (ADD) Daejeon 34188 South Korea
- Department of ChemistryKyungpook National University Daegu 41566 South Korea
| | - Young‐Su Jeong
- Agency for Defense Development (ADD) Daejeon 34188 South Korea
| | - Young Jin Koh
- Agency for Defense Development (ADD) Daejeon 34188 South Korea
| | - Jae Hwan Lee
- Agency for Defense Development (ADD) Daejeon 34188 South Korea
| | - Hyun‐Woo Nam
- Agency for Defense Development (ADD) Daejeon 34188 South Korea
| | - Juno Lee
- Agency for Defense Development (ADD) Daejeon 34188 South Korea
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Ewing KJ, Sanghera J, Major KJ, Farrell ME, Holthoff EL, Pellegrino PM. Infrared Reflectance Spectroscopic Evaluation of Inkjet Printed Standards of Cyclotrimethylenetrinitramine (RDX) on Aluminum Substrates. APPLIED SPECTROSCOPY 2019; 73:214-220. [PMID: 30347995 DOI: 10.1177/0003702818809944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The Department of Defense (DOD) and first responder communities are evaluating and developing optical systems for the detection and identification of explosives and components used for assembling homemade explosives (HMEs). Emerging detection technologies must be evaluated with authentic hazard material concentrations to ensure their accurate and reliable use in the field. In this work, infrared (IR) reflectance spectra over the spectral rage of 1000-1700 cm-1 were collected for different concentrations of inkjet-printed RDX (cyclotrimethylenetrinitramine) samples deposited onto aluminum substrates. A plot of the integrated area of both the symmetric and asymmetric NO2 vibrational bands for RDX on aluminum exhibited good linearity over the concentration range 20-500 µg/cm2. Detection limits for RDX on an aluminum surface were calculated to be 10.7 µg/cm2 for the symmetric NO2 vibrational band and 1.4 µg/cm2 for the asymmetric NO2 vibrational band. Evaluation of the NO2 vibrational band areas at different locations of the RDX array demonstrated that the samples exhibited good homogeneity across the surface. The concentration of an unknown sample of RDX on aluminum was determined using the fitted equations; results showed good agreement between the calculated and actual RDX surface concentration. The lot-to-lot variation of RDX on the aluminum surface was compared using the long wavelength infrared (LWIR) spectral band areas for two different lots of standards printed at the same RDX surface concentration. Results showed excellent lot-to-lot agreement indicating good reproducibility of the standards for RDX.
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10
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Quantum Cascade Laser Infrared Spectroscopy for Online Monitoring of Hydroxylamine Nitrate. Int J Anal Chem 2018; 2018:7896903. [PMID: 30344609 PMCID: PMC6174729 DOI: 10.1155/2018/7896903] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 07/26/2018] [Accepted: 08/29/2018] [Indexed: 11/18/2022] Open
Abstract
We describe a new approach for high sensitivity and real-time online measurements to monitor the kinetics in the processing of nuclear materials and other chemical reactions. Mid infrared (Mid-IR) quantum cascade laser (QCL) high-resolution spectroscopy was used for rapid and continuous sampling of nitrates in aqueous and organic reactive systems, using pattern recognition analysis and high sensitivity to detect and identify chemical species. In this standoff or off-set method, the collection of a sample for analysis is not required. To perform the analysis, a flow cell was used for in situ sampling of a liquid slipstream. A prototype was designed based on attenuated total reflection (ATR) coupled with the QCL beam to detect and identify chemical changes and be deployed in hostile environments, either radiological or chemical. The limit of detection (LOD) and the limit of quantification (LOQ) at 3σ for hydroxylamine nitrate ranged from 0.3 to 3 and from 3.5 to 10 g·L−1, respectively, for the nitrate system at three peaks with wavelengths between 3.8 and 9.8 μm.
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11
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Kilgus J, Duswald K, Langer G, Brandstetter M. Mid-Infrared Standoff Spectroscopy Using a Supercontinuum Laser with Compact Fabry-Pérot Filter Spectrometers. APPLIED SPECTROSCOPY 2018; 72:634-642. [PMID: 29164925 DOI: 10.1177/0003702817746696] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Mid-infrared (MIR) supercontinuum (SC) lasers are an attractive new option in the field of IR spectroscopy, especially for standoff detection. Supercontinuum radiation unites high brightness, high spatial coherence, and broadband spectral coverage, thereby surpassing thermal IR sources and challenging quantum cascade lasers. The employed SC source operates in the spectral region of 1.2-4.6 µm, filling the spectral gap where quantum cascade lasers lack broader availability. In this work, the SC radiation was recorded by compact Fabry-Pérot filter spectrometers ideally suited for sensitive standoff detection with real-time capability. The noise performance of the setup and measurements of different substances at standoff distances are presented, e.g., of different paints on a metal surface and an explosive precursor. Furthermore, the real-time capability of the setup is demonstrated by monitoring the evaporation of liquid 2-propanol.
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Affiliation(s)
- Jakob Kilgus
- RECENDT - Research Center for Non Destructive Testing, Linz, Austria
| | - Kristina Duswald
- RECENDT - Research Center for Non Destructive Testing, Linz, Austria
| | - Gregor Langer
- RECENDT - Research Center for Non Destructive Testing, Linz, Austria
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12
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Nabiev SS, Palkina LA. Modern technologies for detection and identification of explosive agents and devices. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B 2017. [DOI: 10.1134/s1990793117050190] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Rasskazov G, Ryabtsev A, Dantus M. Eye-safe near-infrared trace explosives detection and imaging. OPTICS EXPRESS 2017; 25:5832-5840. [PMID: 28381055 DOI: 10.1364/oe.25.005832] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We report the development of a non-contact no-reagents system operating in the eye-safe 1560-1800 nm wavelength range for standoff trace detection of explosives and high-speed imaging. Experimental results are provided for a number of chemicals including explosives on a variety of surfaces at sub-microgram per cm2 concentration. Chemically specific images were collected at 0.06 ms per pixel. Results from this effort indicate that the combination of modern industrial fiber lasers and nonlinear optical spectroscopy can address next generation eye-safe trace detection of chemicals including explosives.
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Major KJ, Poutous MK, Dunnill KF, Deguzman PC, Sanghera JS, Aggarwal ID, Ewing KJ. Biomimetic Optical-Filter Detection System for Discrimination of Infrared Chemical Signatures. Anal Chem 2016; 88:11491-11497. [PMID: 27934095 DOI: 10.1021/acs.analchem.6b02674] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Optical-filter-based chemical sensors have the potential to dramatically alter the field of hazardous materials sensing. Such devices could be constructed using inexpensive components, in a small and lightweight package, for sensing hazardous chemicals in defense, industrial, and environmental applications. Filter-based sensors can be designed to mimic human color vision. Recent developments in this field have used this approach to discriminate between strongly overlapping chemical signatures in the mid-infrared. Reported work relied on using numerically filtered FTIR spectra to model the infrared biomimetic detection methodology. While these findings are encouraging, further advancement of this technique requires the collection and evaluation of directly filtered data, using an optical system without extensive numerical spectral analysis. The present work describes the design and testing of an infrared optical breadboard system that uses the biomimetic mammalian color-detection approach to chemical sensing. The set of chemicals tested includes one target chemical, fuel oil, along with two strongly overlapping interferents, acetone and hexane. The collected experimental results are compared with numerically filtered FTIR spectral data. The results show good agreement between the numerically filtered data model and the data collected using the optical breadboard system. It is shown that the optical breadboard system is operating as expected based on modeling and can be used for sensing and discriminating between chemicals with strongly overlapping absorption bands in the mid-infrared.
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Affiliation(s)
- Kevin J Major
- Sotera Defense Solutions, Herndon, Virginia 20171, United States
| | - Menelaos K Poutous
- Department of Physics and Optical Science, UNC Charlotte , Charlotte, North Carolina 28223, United States
| | - Kevin F Dunnill
- Department of Physics and Optical Science, UNC Charlotte , Charlotte, North Carolina 28223, United States
| | - Panfilo C Deguzman
- Center for Optoelectronics and Optical Communications, UNC Charlotte , Charlotte, North Carolina 28223, United States
| | - Jasbinder S Sanghera
- Optical Sciences Division, U.S. Naval Research Laboratory, Washington DC, 20375, United States
| | - Ishwar D Aggarwal
- Sotera Defense Solutions, Herndon, Virginia 20171, United States.,Department of Physics and Optical Science, UNC Charlotte , Charlotte, North Carolina 28223, United States
| | - Kenneth James Ewing
- Optical Sciences Division, U.S. Naval Research Laboratory, Washington DC, 20375, United States
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Sun J, Deng H, Liu N, Wang H, Yu B, Li J. Mid-infrared gas absorption sensor based on a broadband external cavity quantum cascade laser. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:123101. [PMID: 28040920 DOI: 10.1063/1.4968041] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We developed a laser absorption sensor based on a pulsed, broadband tunable external cavity quantum cascade laser (ECQCL) centered at 1285 cm-1. Unlike traditional infrared spectroscopy system, a quartz crystal tuning fork (QCTF) as a light detector was used for laser signal detection. Fast Fourier transform was applied to extract vibration intensity information of QCTF. The sensor system is successfully tested on nitrous oxide (N2O) spectroscopy measurements and compared with a standard infrared detector. The wide wavelength tunability of ECQCL will allow us to access the fundamental vibrational bands of many chemical agents, which are well-suited for trace explosive, chemical warfare agent, and toxic industrial chemical detection and spectroscopic analysis.
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Affiliation(s)
- Juan Sun
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, 23061 Hefei, China
| | - Hao Deng
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, 23061 Hefei, China
| | - Ningwu Liu
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, 23061 Hefei, China
| | - Hongliang Wang
- National Deep Sea Center, State Oceanic Administration, 266237 Qingdao, China
| | - Benli Yu
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, 23061 Hefei, China
| | - Jingsong Li
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, 23061 Hefei, China
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Chae I, Khan MF, Song J, Kang T, Lee J, Thundat T. Standoff Mechanical Resonance Spectroscopy Based on Infrared-Sensitive Hydrogel Microcantilevers. Anal Chem 2016; 88:9678-9684. [PMID: 27599117 DOI: 10.1021/acs.analchem.6b02540] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
This paper reports a highly sensitive and selective remote chemical sensing platform for surface-adsorbed trace chemicals by using infrared (IR)-sensitive hydrogel microcantilevers. Poly(ethylene glycol) diacrylate (PEG-DA) hydrogel microcantilevers are fabricated by ultraviolet (UV) curing of PEG-DA prepolymer introduced into a poly(dimethylsiloxane) mold. The resonance frequency of a PEG-DA microcantilever exhibits high thermal sensitivity due to IR irradiation/absorption. When a tunable IR laser beam is reflected off a surface coated with target chemical onto a PEG-DA microcantilever, the resonance frequency of the cantilever shifts in proportion to the chemical nature of the target molecules. Dynamic responses of the PEG-DA microcantilever can be obtained in a range of IR wavelengths using a tunable quantum cascade laser that can form the basis for the standoff mechanical resonance spectroscopy (SMRS). Using this SMRS technique, we have selectively detected three compounds, dimethyl methyl phosphonate (DMMP), cyclotrimethylene trinitramine (RDX), and pentaerythritol tetranitrate (PETN), located 4 m away from the PEG-DA microcantilever detector. The experimentally measured limit of detection for PETN trace using the PEG-DA microcantilever was 40 ng/cm2. Overall, the PEG-DA microcantilever is a promising candidate for further exploration and optimization of standoff detection methods.
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Affiliation(s)
- Inseok Chae
- Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta T6G 2V4, Canada
| | - M Faheem Khan
- Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta T6G 2V4, Canada
| | | | | | | | - Thomas Thundat
- Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta T6G 2V4, Canada
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Galán-Freyle NJ, Pacheco-Londoño LC, Román-Ospino AD, Hernandez-Rivera SP. Applications of Quantum Cascade Laser Spectroscopy in the Analysis of Pharmaceutical Formulations. APPLIED SPECTROSCOPY 2016; 70:1511-1519. [PMID: 27558366 DOI: 10.1177/0003702816662609] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 03/07/2016] [Indexed: 06/06/2023]
Abstract
Quantum cascade laser spectroscopy was used to quantify active pharmaceutical ingredient content in a model formulation. The analyses were conducted in non-contact mode by mid-infrared diffuse reflectance. Measurements were carried out at a distance of 15 cm, covering the spectral range 1000-1600 cm(-1) Calibrations were generated by applying multivariate analysis using partial least squares models. Among the figures of merit of the proposed methodology are the high analytical sensitivity equivalent to 0.05% active pharmaceutical ingredient in the formulation, high repeatability (2.7%), high reproducibility (5.4%), and low limit of detection (1%). The relatively high power of the quantum-cascade-laser-based spectroscopic system resulted in the design of detection and quantification methodologies for pharmaceutical applications with high accuracy and precision that are comparable to those of methodologies based on near-infrared spectroscopy, attenuated total reflection mid-infrared Fourier transform infrared spectroscopy, and Raman spectroscopy.
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Affiliation(s)
- Nataly J Galán-Freyle
- ALERT DHS Center of Excellence for Explosives Research, Department of Chemistry, University of Puerto Rico, USA School of Basic and Biomedical Sciences, Universidad Simón Bolívar, Barranquilla, Colombia
| | - Leonardo C Pacheco-Londoño
- ALERT DHS Center of Excellence for Explosives Research, Department of Chemistry, University of Puerto Rico, USA Environmental Engineering Program, Vice-Rectory for Research, ECCI University, Bogotá, D.C., Colombia
| | | | - Samuel P Hernandez-Rivera
- ALERT DHS Center of Excellence for Explosives Research, Department of Chemistry, University of Puerto Rico, USA
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Kabessa Y, Eyal O, Bar-On O, Korouma V, Yagur-Kroll S, Belkin S, Agranat AJ. Standoff detection of explosives and buried landmines using fluorescent bacterial sensor cells. Biosens Bioelectron 2016; 79:784-8. [PMID: 26774094 DOI: 10.1016/j.bios.2016.01.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 01/03/2016] [Accepted: 01/05/2016] [Indexed: 11/16/2022]
Abstract
A standoff detection scheme for buried landmines and concealed explosive charges is presented. The detection procedure consists of the following: Live bacterial sensor strains, genetically engineered to produce a dose-dependent amount of green fluorescent protein (GFP) in the presence of explosives' vapors, are encapsulated and spread on the suspected area. The fluorescence produced by the bacteria in response to traces of the explosive material in their microenvironment is remotely detected by a phase-locked optoelectronic sampling system. This scheme enables fast direct access to a large minefield area, while obviating the need to endanger personnel and equipment. Moreover, the employment of phase locking detection efficiently isolates the bacterial sensors' fluorescent output from the background optical signals. This facilitates the application of bacterial sensors in an outdoor environment, where control of background illumination is not possible. Using this system, we demonstrate standoff detection of 2,4-DNT both in aqueous solution and when buried in soil, by sensor bacteria either in liquid culture or agar-immobilized, respectively, at a distance of 50 m in a realistic optically noisy environment.
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Affiliation(s)
- Yossef Kabessa
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
| | - Ori Eyal
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Ofer Bar-On
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Victor Korouma
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Sharon Yagur-Kroll
- Department of Plant & Environmental Sciences, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Shimshon Belkin
- Department of Plant & Environmental Sciences, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Aharon J Agranat
- Department of Applied Physics and the Brojde Center for Innovative Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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Castro-Suarez JR, Hidalgo-Santiago M, Hernández-Rivera SP. Detection of highly energetic materials on non-reflective substrates using quantum cascade laser spectroscopy. APPLIED SPECTROSCOPY 2015; 69:1023-1035. [PMID: 26414522 DOI: 10.1366/14-07626] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A quantum cascade laser spectrometer was used to obtain the reflection spectra of highly energetic materials (HEMs) deposited on nonideal, low-reflectivity substrates, such as travel-bag fabric (polyester), cardboard, and wood. Various deposition methods were used to prepare the standards and samples in the study. The HEMs used were the nitroaromatic explosive 2,4,6-trinitrotoluene (TNT), the aliphatic nitrate ester pentaerythritol tetranitrate (PETN), and the aliphatic nitramine 1,3,5-trinitroperhydro-1,3,5-triazine (RDX). Chemometrics algorithms were applied to analyze the recorded spectra. Partial least squares (PLS) regression analysis was used to find the best correlation between the infrared signals and the surface concentrations of the samples, and PLS combined with discriminant analysis (PLS-DA) was used to discriminate, classify, and identity similarities in the spectral datasets. Several preprocessing steps were applied to prepare the mid-infrared spectra of HEMs deposited on the target substrates. The results demonstrate that the infrared vibrational method described in this study is well suited for the rapid screening analysis of HEMs on low-reflectivity substrates when a supervised model has been previously constructed or when a reference spectrum of the clean substrate can be acquired to be subtracted from the HEM-substrate spectrum.
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Affiliation(s)
- John R Castro-Suarez
- University of Puerto Rico-Mayagüez, ALERT DHS Center of Excellence for Explosives Research, Department of Chemistry, Mayagüez, Puerto Rico 00681
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Zaharov VV, Farahi RH, Snyder PJ, Davison BH, Passian A. Karhunen-Loève treatment to remove noise and facilitate data analysis in sensing, spectroscopy and other applications. Analyst 2015; 139:5927-35. [PMID: 25252650 DOI: 10.1039/c4an01300j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Resolving weak spectral variations in the dynamic response of materials that are either dominated or excited by stochastic processes remains a challenge. Responses that are thermal in origin are particularly relevant examples due to the delocalized nature of heat. Despite its inherent properties in dealing with stochastic processes, the Karhunen-Loève expansion has not been fully exploited in measurement of systems that are driven solely by random forces or can exhibit large thermally driven random fluctuations. Here, we present experimental results and analysis of the archetypes (a) the resonant excitation and transient response of an atomic force microscope probe by the ambient random fluctuations and nanoscale photothermal sample response, and (b) the photothermally scattered photons in pump-probe spectroscopy. In each case, the dynamic process is represented as an infinite series with random coefficients to obtain pertinent frequency shifts and spectral peaks and demonstrate spectral enhancement for a set of compounds including the spectrally complex biomass. The considered cases find important applications in nanoscale material characterization, biosensing, and spectral identification of biological and chemical agents.
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Affiliation(s)
- V V Zaharov
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6123, USA.
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Li JS, Yu B, Fischer H, Chen W, Yalin AP. Contributed review: quantum cascade laser based photoacoustic detection of explosives. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:031501. [PMID: 25832204 DOI: 10.1063/1.4916105] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Detecting trace explosives and explosive-related compounds has recently become a topic of utmost importance for increasing public security around the world. A wide variety of detection methods and an even wider range of physical chemistry issues are involved in this very challenging area. Optical sensing methods, in particular mid-infrared spectrometry techniques, have a great potential to become a more desirable tools for the detection of explosives. The small size, simplicity, high output power, long-term reliability make external cavity quantum cascade lasers (EC-QCLs) the promising spectroscopic sources for developing analytical instrumentation. This work reviews the current technical progress in EC-QCL-based photoacoustic spectroscopy for explosives detection. The potential for both close-contact and standoff configurations using this technique is completely presented over the course of approximately the last one decade.
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Affiliation(s)
- J S Li
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, Hefei, China
| | - B Yu
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, Hefei, China
| | - H Fischer
- Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz, Germany
| | - W Chen
- Laboratoire de Physicochimie de l'Atmosphére, Université du Littoral Côte d'Opale, Dunkerque, France
| | - A P Yalin
- Department of Mechanical Engineering, Colorado State University, Fort Collins, Colorado 80523-1374, USA
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Castro-Suarez JR, Pacheco-Londoño LC, Vélez-Reyes M, Diem M, Tague TJ, Hernandez-Rivera SP. FT-IR standoff detection of thermally excited emissions of trinitrotoluene (TNT) deposited on aluminum substrates. APPLIED SPECTROSCOPY 2013; 67:181-186. [PMID: 23622437 DOI: 10.1366/11-06229] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A standoff detection system was assembled by coupling a reflecting telescope to a Fourier transform infrared spectrometer equipped with a cryo-cooled mercury cadmium telluride detector and used for detection of solid-phase samples deposited on substrates. Samples of highly energetic materials were deposited on aluminum substrates and detected at several collector-target distances by performing passive-mode, remote, infrared detection measurements on the heated analytes. Aluminum plates were used as support material, and 2,4,6-Trinitrotoluene (TNT) was used as the target. For standoff detection experiments, the samples were placed at different distances (4 to 55 m). Several target surface temperatures were investigated. Partial least squares regression analysis was applied to the analysis of the intensities of the spectra obtained. Overall, standoff detection in passive mode was useful for quantifying TNT deposited on the aluminum plates with high confidence up to target-collector distances of 55 m.
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23
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Farahi RH, Passian A, Tetard L, Thundat T. Critical issues in sensor science to aid food and water safety. ACS NANO 2012; 6:4548-4556. [PMID: 22564109 DOI: 10.1021/nn204999j] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The stability of food and water supplies is widely recognized as a global issue of fundamental importance. Sensor development for food and water safety by nonconventional assays continues to overcome technological challenges. The delicate balance between attaining adequate limits of detection, chemical fingerprinting of the target species, dealing with the complex food matrix, and operating in difficult environments are still the focus of current efforts. While the traditional pursuit of robust recognition methods remains important, emerging engineered nanomaterials and nanotechnology promise better sensor performance but also bring about new challenges. Both advanced receptor-based sensors and emerging non-receptor-based physical sensors are evaluated for their critical challenges toward out-of-laboratory applications.
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Affiliation(s)
- R H Farahi
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6123, USA
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Abstract
Raman spectroscopy is an analytical technique with vast applications in the homeland security and defense arenas. The Raman effect is defined by the inelastic interaction of the incident laser with the analyte molecule’s vibrational modes, which can be exploited to detect and identify chemicals in various environments and for the detection of hazards in the field, at checkpoints, or in a forensic laboratory with no contact with the substance. A major source of error that overwhelms the Raman signal is fluorescence caused by the background and the sample matrix. Novel methods are being developed to enhance the Raman signal’s sensitivity and to reduce the effects of fluorescence by altering how the hazard material interacts with its environment and the incident laser. Basic Raman techniques applicable to homeland security applications include conventional (off-resonance) Raman spectroscopy, surface-enhanced Raman spectroscopy (SERS), resonance Raman spectroscopy, and spatially or temporally offset Raman spectroscopy (SORS and TORS). Additional emerging Raman techniques, including remote Raman detection, Raman imaging, and Heterodyne imaging, are being developed to further enhance the Raman signal, mitigate fluorescence effects, and monitor hazards at a distance for use in homeland security and defense applications.
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Abstract
The safety of the food supply is a subject of intense interest to consumers, particularly as a result of large-scale outbreaks that involve hundreds and sometimes thousands of consumers. During the last decade, this concern about food safety has expanded to include the diets of companion animals as a result of several incidences of chemical toxicities and infectious disease transmission. This has led to increased research into the causes and controls for these hazards for both companion animals and their owners. The following summary provides an introduction to the issues, challenges and new tools being developed to ensure that commercial pet foods are both nutritious and safe.
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Menzel S, Diehl L, Pflügl C, Goyal A, Wang C, Sanchez A, Turner G, Capasso F. Quantum cascade laser master-oscillator power-amplifier with 1.5 W output power at 300 K. OPTICS EXPRESS 2011; 19:16229-16235. [PMID: 21934985 DOI: 10.1364/oe.19.016229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report quantum cascade laser (QCL) master-oscillator power-amplifiers (MOPAs) at 300 K reaching output power of 1.5 W for tapered devices and 0.9 W for untapered devices. The devices display single-longitudinal-mode emission at λ = 7.26 µm and single-transverse-mode emission at TM(00). The maximum amplification factor is 12 dB for the tapered devices.
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Affiliation(s)
- Stefan Menzel
- Harvard University, School of Engineering and Applied Sciences, 29 Oxford St., Cambridge, MA 02138, USA
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27
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Rao GN, Karpf A. External cavity tunable quantum cascade lasers and their applications to trace gas monitoring. APPLIED OPTICS 2011; 50:A100-A115. [PMID: 21283214 DOI: 10.1364/ao.50.00a100] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Since the first quantum cascade laser (QCL) was demonstrated approximately 16 years ago, we have witnessed an explosion of interesting developments in QCL technology and QCL-based trace gas sensors. QCLs operate in the mid-IR region (3-24 μm) and can directly access the rotational vibrational bands of most molecular species and, therefore, are ideally suited for trace gas detection with high specificity and sensitivity. These sensors have applications in a wide range of fields, including environmental monitoring, atmospheric chemistry, medical diagnostics, homeland security, detection of explosive compounds, and industrial process control, to name a few. Tunable external cavity (EC)-QCLs in particular offer narrow linewidths, wide ranges of tunability, and stable power outputs, which open up new possibilities for sensor development. These features allow for the simultaneous detection of multiple species and the study of large molecules, free radicals, ions, and reaction kinetics. In this article, we review the current status of EC-QCLs and sensor developments based on them and speculate on possible future developments.
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Affiliation(s)
- Gottipaty N Rao
- Department of Physics, Adelphi University, Garden City, New York 11530, USA.
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28
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Grills DC, Cook AR, Fujita E, George MW, Preses JM, Wishart JF. Application of external-cavity quantum cascade infrared lasers to nanosecond time-resolved infrared spectroscopy of condensed-phase samples following pulse radiolysis. APPLIED SPECTROSCOPY 2010; 64:563-570. [PMID: 20537222 DOI: 10.1366/000370210791414344] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Pulse radiolysis, utilizing short pulses of high-energy electrons from accelerators, is a powerful method for rapidly generating reduced or oxidized species and other free radicals in solution. Combined with fast time-resolved spectroscopic detection (typically in the ultraviolet/visible/near-infrared), it is invaluable for monitoring the reactivity of species subjected to radiolysis on timescales ranging from picoseconds to seconds. However, it is often difficult to identify the transient intermediates definitively due to a lack of structural information in the spectral bands. Time-resolved vibrational spectroscopy offers the structural specificity necessary for mechanistic investigations but has received only limited application in pulse radiolysis experiments. For example, time-resolved infrared (TRIR) spectroscopy has only been applied to a handful of gas-phase studies, limited mainly by several technical challenges. We have exploited recent developments in commercial external-cavity quantum cascade laser (EC-QCL) technology to construct a nanosecond TRIR apparatus that has allowed, for the first time, TRIR spectra to be recorded following pulse radiolysis of condensed-phase samples. Near single-shot sensitivity of DeltaOD <1 x 10(-3) has been achieved, with a response time of <20 ns. Using two continuous-wave EC-QCLs, the current apparatus covers a probe region from 1890-2084 cm(-1), and TRIR spectra are acquired on a point-by-point basis by recording transient absorption decay traces at specific IR wavelengths and combining these to generate spectral time slices. The utility of the apparatus has been demonstrated by monitoring the formation and decay of the one-electron reduced form of the CO(2) reduction catalyst, [Re(I)(bpy)(CO)(3)(CH(3)CN)](+), in acetonitrile with nanosecond time resolution following pulse radiolysis. Characteristic red-shifting of the nu(CO) IR bands confirmed that one-electron reduction of the complex took place. The availability of TRIR detection with high sensitivity opens up a wide range of mechanistic pulse radiolysis investigations that were previously difficult or impossible to perform with transient UV/visible detection.
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Affiliation(s)
- David C Grills
- Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973-5000, USA.
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Laser-based standoff detection of explosives: a critical review. Anal Bioanal Chem 2009; 395:259-74. [DOI: 10.1007/s00216-009-2844-3] [Citation(s) in RCA: 182] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Revised: 05/05/2009] [Accepted: 05/07/2009] [Indexed: 11/26/2022]
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Laser-induced breakdown spectroscopy for detection of explosives residues: a review of recent advances, challenges, and future prospects. Anal Bioanal Chem 2009; 395:283-300. [PMID: 19418042 DOI: 10.1007/s00216-009-2802-0] [Citation(s) in RCA: 181] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2009] [Revised: 04/08/2009] [Accepted: 04/14/2009] [Indexed: 10/20/2022]
Abstract
In this review we discuss the application of laser-induced breakdown spectroscopy (LIBS) to the problem of detection of residues of explosives. Research in this area presented in open literature is reviewed. Both laboratory and field-tested standoff LIBS instruments have been used to detect explosive materials. Recent advances in instrumentation and data analysis techniques are discussed, including the use of double-pulse LIBS to reduce air entrainment in the analytical plasma and the application of advanced chemometric techniques such as partial least-squares discriminant analysis to discriminate between residues of explosives and non-explosives on various surfaces. A number of challenges associated with detection of explosives residues using LIBS have been identified, along with their possible solutions. Several groups have investigated methods for improving the sensitivity and selectivity of LIBS for detection of explosives, including the use of femtosecond-pulse lasers, supplemental enhancement of the laser-induced plasma emission, and complementary orthogonal techniques. Despite the associated challenges, researchers have demonstrated the tremendous potential of LIBS for real-time detection of explosives residues at standoff distances.
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