Download or read book Compact Femtosecond Pulse Approach to Explosives Detection Combining InN Based Time Domain Terahertz Spectroscopy and Laser Induced Breakdown Spectroscopy written by and published by . This book was released on 2008 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: The feasibility of attaining improved explosives detection and identification using complementary InN-based time-domain terahertz spectroscopy (TDTS) and laser-induced breakdown spectroscopy (LIBS) techniques employing 1550-nm femtosecond (fs) pulse technology has been investigated. The use of very low-energy, ultra-short, near-infrared laser pulses for both TDTS and LIBS has been demonstrated. Novel approaches exploiting polarization fields in wurtzite nitride semiconductors such as InN and GaN led to an enhancement of TMz generation by more than a factor of 3 relative to more conventional sources fabricated from these materials. These results could lead to improved TMz sources at fs fiber laser wavelengths of interest, with further advances in materials quality. Threshold LIBS pulse energies used in this investigation are the lowest reported to date, and gated detection is not required, potentially leading to an overall simpler and inexpensive system more amenable to field use. Finally, the use of low pulse energies in these studies currently available from more compact mode-locked fiber laser systems indicates potential for incorporation in field-deployable explosives-detection platforms.

Download or read book Laser Based Optical Detection of Explosives written by Paul M. Pellegrino and published by CRC Press. This book was released on 2018-09-03 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser-Based Optical Detection of Explosives offers a comprehensive review of past, present, and emerging laser-based methods for the detection of a variety of explosives. This book: Considers laser propagation safety and explains standard test material preparation for standoff optical-based detection system evaluation Explores explosives detection using deep ultraviolet native fluorescence, Raman spectroscopy, laser-induced breakdown spectroscopy, reflectometry, and hyperspectral imaging Examines photodissociation followed by laser-induced fluorescence, photothermal methods, cavity-enhanced absorption spectrometry, and short-pulse laser-based techniques Describes the detection and recognition of explosives using terahertz-frequency spectroscopic techniques Each chapter is authored by a leading expert on the respective technology, and is structured to supply historical perspective, address current advantages and challenges, and discuss novel research and applications. Readers are left with an in-depth understanding and appreciation of each technology’s capabilities and potential for standoff hazard detection.

Download or read book Terahertz and Mid Infrared Radiation Detection of Explosives and CBRN Using Terahertz written by Mauro F. Pereira and published by Springer. This book was released on 2014-03-10 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: The reader will find here a timely update on new THz sources and detection schemes as well as concrete applications to the detection of Explosives and CBRN. Included is a method to identify hidden RDX-based explosives (pure and plastic ones) in the frequency domain study by Fourier Transformation, which has been complemented by the demonstration of improvement of the quality of the images captured commercially available THz passive cameras. The presented examples show large potential for the detection of small hidden objects at long distances (6-10 m). Complementing the results in the short-wavelength range, laser spectroscopy with a mid-infrared, room temperature, continuous wave, DFB laser diode and high performance DFB QCL have been demonstrated to offer excellent enabling sensor technologies for environmental monitoring, medical diagnostics, industrial and security applications. From the new source point of view a number of systems have been presented - From superconductors to semiconductors, e.g. Detection of Terahertz Waves from Superconducting Bi2Sr2CaCu2O8+δ Intrinsic Josephson Junctions. The quest for a compact room temperature THz source and the recent advances in high power mid-IR QCLs lead to the development of a semiconductor THz source based on intracavity difference frequency generation. Furthermore, alternative electrically pumped THz sources based on the high emission efficiency predicted for polaritonic states in the ultra-strong coupling regime led to the demonstration of electroluminescent devices. Finally, antipolaritons in dispersive media were discussed and different aspects of the interaction of THz radiation with biomatter were presented.

Download or read book Laser Induced Breakdown Spectroscopy written by Jagdish P. Singh and published by Elsevier. This book was released on 2020-06-02 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser-Induced Breakdown Spectroscopy, Second Edition, covers the basic principles and latest developments in instrumentation and applications of Laser Induced Breakdown Spectroscopy (LIBS). Written by active experts in the field, it serves as a useful resource for analytical chemists and spectroscopists, as well as graduate students and researchers engaged in the fields of combustion, environmental science, and planetary and space exploration. This fully revised second edition includes several new chapters on new LIBS techniques as well as several new applications, including flame and off-gas measurement, pharmaceutical samples, defense applications, carbon sequestration and site monitoring, handheld instruments, and more. LIBS has rapidly developed into a major analytical technology with the capability of detecting all chemical elements in a sample, of real- time response, and of close-contact or stand-off analysis of targets. It does not require any sample preparation, unlike conventional spectroscopic analytical techniques. Samples in the form of solids, liquids, gels, gases, plasmas, and biological materials (like teeth, leaves, or blood) can be studied with almost equal ease. This comprehensive reference introduces the topic to readers in a simple, direct, and accessible manner for easy comprehension and maximum utility. - Covers even more applications of LIBS beyond the first edition, including combustion, soil physics, environment, and life sciences - Includes new chapters on LIBS techniques that have emerged in the last several years, including Femtosecond LIBS and Molecular LIBS - Provides inspiration for future developments in this rapidly growing field in the concluding chapter

Download or read book MURI Real Time Explosive Specific Chemical Sensors Spectroscopic and Time Domain Detection of Trace Explosives in Condensed and Vapor Phases written by and published by . This book was released on 2008 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: Under this MURI, research into the use of terahertz spectroscopy, femtosecond laser-induced breakdown spectroscopy, infrared spectroscopy, laser ionization-mass spectrometry and cavity ring-down spectroscopy for explosives detection was pursued. Fundamental studies have been completed that contribute to our understanding of explosives and how they behave when being sensed using the techniques selected for study. The highest level conclusion reached in this program is that all of the techniques have the ability to detect explosives in the environment - the critical issues that are still unresolved are the ultimate selectivities and sensitivities of these techniques. At this time, it is clear that the current sensitivities of terahertz techniques allow for detection of column/surface concentrations of approximately 10 micro-g/cm2, laser induced breakdown spectroscopy can detect at levels below 10 micro-g/cm2, and cavity ring-down spectroscopy can detect vapor phase concentrations below 1 ppb. While these levels of detection have been demonstrated through work in the MURI, more important results have been obtained that point in critical directions for the success of sensing schemes that might be pursued in the future.

Download or read book Laser Induced Breakdown Spectroscopy in Biological Forensic and Materials Sciences written by Gábor Galbács and published by Springer Nature. This book was released on 2022-12-13 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a comprehensive overview of recent advances in the area of laser-induced breakdown spectroscopy (LIBS), focusing on its application to biological, forensic and materials sciences. LIBS, which was previously mainly used by physicists, chemists and in the industry, has now become a very useful tool with great potential in these other fields as well. LIBS has a unique set of characteristics including minimal destructiveness, remote sensing capabilities, potential portability, extremely high information content, trace analytical sensitivity and high throughput. With its content divided into two main parts, this book provides not only an introduction to the analytical capabilities and methodology, but also an overview of the results of recent applications in the above fields. The application-oriented, multidisciplinary approach of this work is also reflected in the diversity of the expert contributors. Given its breadth, this book will appeal to students, researchers and professionals interested in solving analytical/diagnostic/material characterization tasks with the application of LIBS.

Download or read book Laser Induced Breakdown Spectroscopy written by Sergio Musazzi and published by Springer. This book was released on 2014-07-08 with total page 577 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with the Laser-Induced Breakdown Spectroscopy (LIBS) a widely used atomic emission spectroscopy technique for elemental analysis of materials. It is based on the use of a high-power, short pulse laser excitation. The book is divided into two main sections: the first one concerning theoretical aspects of the technique, the second one describing the state of the art in applications of the technique in different scientific/technological areas. Numerous examples of state of the art applications provide the readers an almost complete scenario of the LIBS technique. The LIBS theoretical aspects are reviewed. The book helps the readers who are less familiar with the technique to understand the basic principles. Numerous examples of state of the art applications give an almost complete scenario of the LIBS technique potentiality. These examples of applications may have a strong impact on future industrial utilization. The authors made important contributions to the development of this field.

Download or read book Detection of Bulk Explosives Advanced Techniques against Terrorism written by Hiltmar Schubert and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Detection of Bulk Explosives: Advanced Techniques against Terrorism contains reviews of: existing and emerging bulk explosives detection techniques; scientific and technical policy of the Federal Border Service of the Russian Federation; challenges in application and evaluation of EDS systems for aviation security; multi-sensor approach to explosives detection. There are also reports devoted to the following individual explosive detection techniques: X-ray systems in airports; neutron in, gamma out techniques; neutron and gamma backscattering; nuclear quadruple resonance, including remote NQR; sub-surface radars; microwave scanners; laser-induced burst spectroscopy (LIBS); acoustic sensors; nonlinear location (NUD); systems for localization and destruction of explosive objects.

Download or read book Explosives Detection written by Lorenzo Capineri and published by Springer Nature. This book was released on 2020-01-29 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents selected contributions from the “Advanced Research Workshop on Explosives Detection” hosted by the Department of Information Engineering of the University of Florence, Italy in 2018. The main goal of the workshop was to find out how Science for Peace and Security projects in the field of Explosives Detection contribute to the development and/or refinement of scientific and technical knowledge and competencies. The findings of the workshop, presented in the last section of the book, determine future actions and direction of the SPS Programme in the field of explosives detection and management.The NATO Science for Peace and Security (SPS) Programme, promotes dialogue and practical cooperation between NATO member states and partner nations based on scientific research, technological innovation and knowledge exchange. Several initiatives were launched in the field of explosive detection and clearance, as part of NATO’s enhanced role in the international fight against terrorism. Experts and scientists from NATO members and partner countries have been brought together in multi-year projects, within the framework of the SPS Programme, to cooperate in the scientific research in explosive detection field, developing new technologies and methods to be implemented in order to detect explosive substances in different contexts.

Download or read book Laser Based Detection Methods for Explosives written by and published by . This book was released on 2007 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many well-known explosive detection techniques such as mass spectrometry and chromatography rely on close-contact sampling of surface residues or explosive vapors. Effective detection of explosive materials using laser-based methods has been demonstrated in close-contact and standoff (tens of meters) configurations. This work reviews the current technical progress in laser-based explosive detection methods such as infrared spectroscopy, Raman spectroscopy, terahertz spectroscopy, laser-induced breakdown spectroscopy, and photo fragmentation. The potential for standoff detection using these techniques is also discussed.

Download or read book Assessment of Millimeter Wave and Terahertz Technology for Detection and Identification of Concealed Explosives and Weapons written by National Research Council and published by National Academies Press. This book was released on 2007-04-06 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: The security of the U.S. commercial aviation system has been a growing concern since the 1970's when the hijacking of aircraft became a serious problem. Over that period, federal aviation officials have been searching for more effective ways for non-invasive screening of passengers, luggage, and cargo to detect concealed explosives and weapons. To assist in this effort, the Transportation Security Administration (TSA) asked the NRC for a study of emerging screening technologies. This report-the third of four-focuses on currently maturing millimeter-wavelength/terahertz imaging and spectroscopy technologies that offer promise in meeting aviation security requirements. The report provides a description of the basic operation of these imaging systems, an assessment of their component technologies, an analysis of various system concepts, and an implementation strategy for deployment of millimeter-wavelength/terahertz technology screening systems.

Download or read book Tailored Ultrafast Pulses for Selective Energetic Residue Sampling written by and published by . This book was released on 2008 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Femtosecond pulses offer several advantages over more conventional nanosecond pulses for laser-induced breakdown spectroscopy applications. These advantages include improved ablation, lower breakdown threshold, more efficient energy deposition, and less thermal damage to surrounding areas. The scope of this work is to determine if femtosecond laser-induced breakdown spectroscopy offers advantages for detecting trace explosive residues. Also, additional laser pulses, focused and nonfocused, were used to enhance the emission signal. It was determined that the lower breakdown threshold was the most important characteristic of the femtosecond pulse for, explosive residue detection. Enhancement of the plasma becomes more critical if lower-energy pulses are used since emission intensity is sacrificed.

Download or read book Counterterrorist Detection Techniques of Explosives written by Jehuda Yinon and published by Elsevier. This book was released on 2011-10-13 with total page 455 pages. Available in PDF, EPUB and Kindle. Book excerpt: The detection of hidden explosives has become an issue of utmost importance in recent years. While terrorism is not new to the international community, recent terrorist attacks have raised the issue of detection of explosives and have generated a great demand for rapid, sensitive and reliable methods for detecting hidden explosives. Counterterrorist Detection Techniques of Explosives covers recent advances in this area of research including vapor and trace detection techniques (chemiluminescence, mass spectrometry, ion mobility spectrometry, electrochemical methods and micromechanical sensors, such as microcantilevers) and bulk detection techniques (neutron techniques, nuclear quadrupole resonance, x-ray diffraction imaging, millimeter-wave imaging, terahertz imaging and laser techniques). This book will be of interest to any scientists involved in the design and application of security screening technologies including new sensors and detecting devices which will prevent the smuggling of bombs and explosives. * Covers latest advances in vapor and trace detection techniques and bulk detection techniques* Reviews both current techniques and those in advanced stages of development* Techniques that are described in detail, including its principles of operation, as well as its applications in the detection of explosives

Download or read book Laser Induced Breakdown Spectroscopy with Improved Detection Sensitivity and Isotopic Discrimination written by Kyle Hartig and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser-induced breakdown spectroscopy (LIBS) could be used to perform rapid, real-time, elemental, and isotopic analysis of materials relevant to nuclear forensics, safeguards, and counterproliferation. The detection sensitivity of LIBS is element dependent and the limits of detection (LODs) are higher than competing techniques used in nuclear forensics like secondary ionization mass-spectroscopy or gamma spectroscopy. LIBS non-invasiveness, small sample size requirements, and a need for minimal or no sample preparation, are the main attributes and moderately responsible for the challenges encountered when identifying and quantifying elements with this technique. Secondly, interference of the individual spectral lines in the plasma emission spectrum limit the LIBS detection selectivity and reliability. Finally, the matrix effects also limit the performance of LIBS since the emission intensity from the target element depends on not only the concentration, but also the chemical and physical properties of the matrix.In this dissertation, optimization of the characteristics of the laser pulse have been pursued and new analysis techniques were introduced to improve LIBS detection sensitivity and isotope selectivity. Optimization of the laser pulse shape through simple and more complex pulse shaping techniques was shown to influence the overall LIBS emission intensity, signal-to-background, and the ionization state of the plasma. Similarly, 2.05 m femtosecond (fs) laser pulses were observed to produce a plasma of lower temperature and density compared to 800 nm fs laser pulses, resulting in an increased signal-to-background ratio (SBR). Ab initio mod- eling was applied to show that the reduced plasma temperature and density for longer wavelength laser pulses leads to the increased SBR.As an extension of LIBS, laser ablation molecular isotopic spectrometry (LAMIS) was adapted for use with fs-laser pulses. Expansion of the LAMIS technique to isotopic analysis of uranium using fs-laser pulses and the capability to per- form this analysis at remote distances through the combination of fs-filamentation LAMIS (F2LAMIS) was demonstrated. The molecular isotope shift for the UO emission band at 593.57 nm was measured to be ~0.05 0.007 nm, which is twice as large as the largest known atomic/ionic isotope shift of 0.025 nm for the 424.43 nm U II emission line. Spatio-temporally resolved spectral and shad- owgraphic measurements showed that the UO species expanded at a slower rate compared to the uranium atomic species.The bulk matrix composition of the sample was observed to affect the measured LIBS and LAMIS signal, and resulted in a reduced analytic capability of the technique for both elemental and isotopic measurement. In specific examples, the measured LIBS emission intensity for an analyte of interest was observed to increase with the presence of a second element of greater concentration, which is the inverse of what is expected for many other analytical techniques. The increase in the analyte emission intensity was studied via temporally resolved plasma and emission diagnostics and through the use of ab initio modeling.The results of this work provide new insights that will aid the development of LIBS/LAMIS as a technique capable of not just elemental analysis, but also isotopic analysis at standoff distances in real time, which is important to remote sensing applications in nuclear forensics, safeguards, and counterproliferation.

Download or read book Detection of Energetic Materials and Explosive Residues with Laser induced Breakdown Spectroscopy written by and published by . This book was released on 2007 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser-induced breakdown spectroscopy (LIBS) has been investigated for the detection of energetic materials. After an initial survey of explosives and propellants, key elemental and molecular emission lines in the LIBS spectra were identified. Techniques for improving the sensitivity and selectivity of LIBS for explosives detection, such as the use of an argon buffer gas and double pulse LIBS, have been investigated with laboratory and field-portable instruments. We present results demonstrating the ability of LIBS to discriminate between energetic and non-energetic materials.

Download or read book Detection of Energetic Materials and Explosive Residues With Laser Induced Breakdown Spectroscopy 1 Laboratory Measurements written by and published by . This book was released on 2007 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser-induced breakdown spectroscopy (LIBS) has been investigated for the detection of energetic materials. After an initial survey of explosives and propellants, key elemental and molecular emission lines in the LIBS spectra were identified. Techniques for improving the sensitivity and selectivity of LIBS for explosives detection, such as the use of an argon buffer gas and double pulse LIBS, have been investigated with laboratory and field-portable instruments. We present results demonstrating the ability of LIBS to discriminate between energetic and non-energetic materials.

Download or read book Stand off Detection of Suicide Bombers and Mobile Subjects written by Hiltmar Schubert and published by Springer Science & Business Media. This book was released on 2006-09-22 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is derived from lectures at an international NATO-Russian Advanced Research Workshop on the Stand-off-Detection of concealed explosives carried by suicide-bombers or in vehicles. Ideally, explosives should be detected by harmless methods at a distance, and unknown to the persons under inspection. The aim is to devise sensing techniques that will allow the shortest developing time sufficient to start commercial production. Short time availability is a prioritizing isssue.