Abstract-Discrimination and identification of RDX/PETN explosives by chemometrics applied to terahertz time-domain spectral imaging

J. Bou-Sleiman, J.-B. Perraud, J.-P. Guillet, P. Mounaix

IMS, CNRS, Bordeaux Univ. (France)

B. Bousquet

CELIA, CNRS, Bordeaux Univ. (France)

N. Palka

Military Univ. of Technology (Poland)

Proc. SPIE 9651, Millimetre Wave and Terahertz Sensors and Technology VIII, 965109 (October 21, 2015); doi:10.1117/12.2197442

http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=2466618

Detection of explosives has always been a priority for homeland security. Jointly, terahertz spectroscopy and imaging are emerging and promising candidates as contactless and safe systems. In this work, we treated data resulting from hyperspectral imaging obtained by THz-time domain spectroscopy, with chemometric tools. We found efficient identification and sorting of targeted explosives in the case of pure and mixture samples. In this aim, we applied to images Principal Component Analysis (PCA) to discriminate between RDX, PETN and mixtures of the two materials, using the absorbance as the key-parameter. Then we applied Partial Least Squares-Discriminant Analysis (PLS-DA) to each pixel of the hyperspectral images to sort the explosives into different classes. The results clearly show successful identification and categorization of the explosives under study.
 © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

Course-Terahertz Technology in Homeland Security and Defense (SC718)

Course Level: Introductory
Instructor: Ruth M. Woodward, HT Consultants Ltd. (United Kingdom)
http://spie.org/x1145.xml?course_id=M0000782&topic_id=5

Course Details

This course will introduce the basic techniques in terahertz technology for imaging and spectroscopy in homeland security and defense. The course reviews the progress of the technology in the security and defense arena, including recent developments in sources and detectors. The focus will be specifically on the application of the technology for improvised explosive device (IED) detection and chemical and biological sensing. The methods required for the successful imaging and spectroscopy of target materials will be discussed, in addition to the appropriate implementation of standards for identifying the viability of terahertz technology in this arena. The student will receive an understanding of the challenges and potential of terahertz technology in homeland security and defense.

Learning Outcomes

This course will enable you to:

• describe the current progress of terahertz technology in homeland security and defense
• explain the signatures observed in the terahertz region and associated merits for time or frequency domain analysis
• understand the limitations of the terahertz technology for stand-off detection
• identify problems associated with image generation and spectroscopy
• understand the appropriate experiments required for identify the viability of terahertz technology in security and defense
• conclude the areas where terahertz technology has potential

Intended Audience

This material is directed at scientists, researchers, managers and government interested in the application of terahertz technology for homeland security and defense initiatives. Those currently in the field of terahertz technology or wishing to enter and explore this field will find this course valuable.

Instructor

Ruth M. Woodward is director and founder of HT Consultants Ltd., a specialist consultancy firm in terahertz technology. She has been involved in the application of terahertz pulsed imaging and spectroscopy to the medical industry since its foundation in 1999. During her PhD research on ‘Terahertz pulsed imaging and spectroscopy applied to dermatology’, she identified a terahertz contrast between diseased and normal tissue in basal cell carcinoma, the most common form of skin cancer, which led to an explosion of interest in the application of terahertz technology to the medical industry, and the subsequent commercialization of terahertz imaging systems in this area. As Chair of SPIE Global Homeland Security Technical Group Standards Subcommittee, she also takes an active interest in the implementation of product and safety standards in security and defense, in addition to alternate methods for improving homeland security.

Abstract-Feasibility of Terahertz Time-Domain Spectroscopy to Detect Tetracyclines Hydrochloride in Infant Milk Powder

Jianyuan Qin , Lijuan Xie , and Yibin Ying

Anal. Chem., Just Accepted Manuscript

DOI: 10.1021/ac503212q

Publication Date (Web): October 27, 2014

Copyright © 2014 American Chemical Society

http://pubs.acs.org/doi/abs/10.1021/ac503212q

We report the use of terahertz time-domain spectroscopy (THz-TDS) to detect tetracyclines hydrochloride (TCsH) in infant milk powder for the first time. Four kinds of TCsH exhibited their unique spectral features in the region of 0.3-1.8 THz. The main spectral features of these TCsH were still detectable when mixed with infant milk powder with concentrations at 1%-50%, even in the ternary mixtures. The results from chemometrics analysis showed that qualitative and quantitative detection of TCsH in infant milk powder could be successfully achieved. The residual predictive deviation (RPD) values of all these TCsH models were all higher than 2, indicating these models were considered good, and could be used in screening purposes. The RPD values of TCH, DTCH and CTCH models were higher than 3, which were considered excellent for prediction purposes. These preliminary results indicated that THz-TDS combined with chemometrics analysis was suitable for detecting the presence of TCsH residues in a food matrix.