Download or read book Development and Application of an Inverse Spatially Offset Raman Spectroscopic Method for the Detection of Concealed Substances written by Thomas Bedward and published by . This book was released on 2017 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the creation of the ʻDark Netʼ in mid-1990ʼs, the way in which drugs are bought, sold, and transported has changed dramatically (Bartlett 2014). A digital age of drug trade has begun, and it has only been growing, with tens of thousands of websites now available on the Darknet, many of which are dedicated to the sale and trade of illicit substances (Anderson 2015). While techniques utilised by Customs and Border Security offices, both domestically and internationally, have evolved to stem this growing problem, the methodologies used by drug transporters and vendors have advanced even more rapidly, causing there to be a growing need for new detection techniques. In 2016, the postal system has become one of the largest channels through which illicit substances are trafficked, with suppliers simply mailing their products to customers, greatly reducing and even removing the risk of ever being caught. Furthermore, suppliers have adopted a new, ʻscatter-gunʼ approach, in which large shipments are broken down and sent in smaller, less obvious quantities. This approach has two main benefits, firstly, shipments are easier and cheaper to transport, and secondly, if one or two smaller parcels are intercepted, the bulk of the shipment is still far more likely to slip by Customs and Border Security offices. It is the combination of these practises, as well as the inability to examine every piece of mail that is sent and received that has helped to create a growing problem and a damaging trend. In this paper, a Spatially Offset Raman Spectroscopy (SORS) method was developed and implemented specifically to detect, identify, and quantify samples of illicit substances concealed within twenty-five common packaging types. Utilising an axicon, conventional Raman spectrometer and chemometric software, it was shown that a rapid and non-destructive SORS method could be easily and successfully implemented for the bulk of packaging materials commonly encountered within Australia and at Australian borders, as well as potentially aiding in the detection and identification of many concealed drug samples. Ultimately, it was found that nineteen of the twenty-five packaging types could be successfully interrogated using the developed method, with strong signals and accurate detections made through envelopes, padded bags, and a variety of tapes, plastics, and papers. Furthermore, it was found that the method could detect and identify complex, powdered samples involving up to four components, as well as detecting target substances through more complex multi-layered parcels with a relatively high degree of accuracy and certainty.

Download or read book Surface Enhanced Raman Spectroscopy written by Marek Prochazka and published by Springer. This book was released on 2015-12-12 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives an overview of recent developments in RS and SERS for sensing and biosensing considering also limitations, possibilities and prospects of this technique. Raman scattering (RS) is a widely used vibrational technique providing highly specific molecular spectral patterns. A severe limitation for the application of this spectroscopic technique lies in the low cross section of RS. Surface-enhanced Raman scattering (SERS) spectroscopy overcomes this problem by 6-11 orders of magnitude enhancement compared with the standard RS for molecules in the close vicinity of certain rough metal surfaces. Thus, SERS combines molecular fingerprint specificity with potential single-molecule sensitivity. Due to the recent development of new SERS-active substrates, labeling and derivatization chemistry as well as new instrumentations, SERS became a very promising tool for many varied applications, including bioanalytical studies and sensing. Both intrinsic and extrinsic SERS biosensing schemes have been employed to detect and identify small molecules, nucleic acids and proteins, and also for cellular and in vivo sensing.

Download or read book Development of Inverse Raman Spectroscopy for Probing Rapidly Decomposing Explosives and Propellants written by and published by . This book was released on 1981 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: The techniques of inverse Raman spectroscopy and coherent anti-stokes Raman spectroscopy are considered for the purpose of development of rapid (single-shot) broad band detection of species in rapidly (explosively) decomposing materials. Experiments using inverse Raman spectroscopy with pulsed ruby laser, broad-band dye, 1-M spectrometer and optical multichannel analyzer are described. Results on benzaldehyde (neat and in mixtures with toluene) yield information on the quantitative limits of inverse Raman detection.

Download or read book Surface enhanced Raman Spectroscopy written by Vinay Bhardwaj and published by . This book was released on 2019 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the last decade, we have seen spurring growth in academic and industrial interest in Raman spectroscopy and its modifications, in particular, Surface-Enhanced Raman Spectroscopy (SERS). This is evident by the number of SERS publications in the last decade, from 580 in 2005 to almost 2000 in 2014. There are now companies worldwide that are dedicated to manufacturing SERS substrate, sensors, and other SERS-based products. The miniaturization of Raman instrumentation from bulky and expensive bench-top designs to inexpensive handheld spectrometers has allowed SERS to be employed as an in situ detection technique. Some examples of the industrial success of Raman and SERS are rapid raw material identification (RMID), Process Analytical Technology (PAT) and drug screening in pharma and biotech industries, continuous surveillance of food, water, and environmental safety, and the diagnosis and continuous monitoring of diseases like cancer, diabetes, etc. This progress in translating Raman and SERS techniques into commercial use and commercial products is possible because of the close collaboration between scientists and engineers. However, the weak signals of Raman spectroscopy is an inherent limitation of the spontaneous Raman spectroscopy technique. Therefore, several modifications have been made, including but not limited to, surface-enhanced Raman spectroscopy (SERS), spatially offset Raman spectroscopy (SORS), transmission Raman spectroscopy (TRS), coherent anti-Stokes Raman spectroscopy (CARS), and tip-enhanced Raman spectroscopy (TERS). Spontaneous Raman spectroscopy has become a one-of-a kind, portable, and affordable technology for in-situ detection and continuous monitoring in resource-limited-settings. The primary focus of this textbook is to try to cover the fundamentals in SERS methods of preparing substrates and sensors, and efficient spectral analysis approaches like chemometrics for diverse applications, listed in the paragraph above. However, with a goal to give a true picture to the audience when assessing the scope of spontaneous Raman and Surface-enhanced Raman for specific applications, we have briefly introduced industrially successful examples of other types of Raman spectroscopy techniques, such as SORS, TRS, and CARS.

Download or read book Raman Spectroscopy written by Dheeraj Kumar Singh and published by Springer Nature. This book was released on with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Raman Spectroscopy written by Gustavo Morari Do Nascimento and published by BoD – Books on Demand. This book was released on 2018-04-18 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives a wide overview of the state-of-the-art applications of Raman spectroscopy in characterization of materials and biomaterials. The Raman signal is intrinsically smaller than other vibrational techniques; however, mainly through intensification processes, such as resonance Raman (RR) and surface-enhanced Raman spectroscopy (SERS), the Raman cross section can be strongly amplified. Thoroughly in these signal amplifications, the study of a diversity of chemical systems and the use of Raman technique for in situ and in vivo measurements is possible. The main goal of this book is to open up to an extended audience the possibilities of uses of Raman spectroscopy. In fact, this collective work will be beneficial to students, teachers, and researchers of many areas who are interested to expand their knowledge about Raman spectroscopy applied to nanotechnology, biotechnology, environmental science, inorganic chemistry, and health sciences.

Download or read book Non Linear Raman Spectroscopy and Its Chemical Aplications written by W. Kiefer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 623 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years a number of non-linear Raman spectroscopic techniques have been substantially developed and are now proving to be powerful methods for the solution of many problems not only in spectroscopy but also in chemistry, physics and biology. These techniques include hyper Rayleigh and hyper Raman spectroscopy, coherent anti-Stokes Raman Spectroscopy (CARS), Raman Gain and In verse Raman Spectroscopy, Photoacoustic Raman Spectroscopy (PARS) and the Raman Induced Kerr Effect (RIKE). Hyper Raman spectro scopy although experimentally difficult is valuable for investi gating transitions which are not active in the infrared or in the linear Raman effect; and the other non-linear Raman effects can provide signal strength and resolution which are orders of magni tude higher than those obtainable with linear Raman spectroscopy. The thirty chapters in this book will form the basis of lectures presented at the NATO Advanced Study Institute in Bad Windsheim, F. R. Germany from August 23 - September 3, 1982.

Download or read book In situ Spectroscopic Techniques at High Pressure written by Andreas Braeuer and published by Elsevier. This book was released on 2015-12-07 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt: In situ Spectroscopic Techniques at High Pressure provides a comprehensive treatment of in-situ applications of spectroscopic techniques at high pressure and their working principles, allowing the reader to develop a deep understanding of which measurements are accessible with each technique, what their limitations are, and for which application each technique is best suited. Coverage is also given to the instrumental requirements for these applications, with respect to the high pressure instrumentation and the spectroscopic components of the equipment. The pedagogical style of the book is supplemented by the inclusion of "study questions" which aim to make it useful for graduate-level courses. Bridges the gap between supercritical fluid science/technology and in-situ spectroscopic techniques Provides a powerful guide to applying spectroscopic techniques as gainful sensors at high pressure Highlights the influence of a high pressure environment and high pressure equipment on spectroscopic techniques Presents a deep understanding of which measurements are accessible with each technique, what their limitations are, and for which application each technique is best suited

Download or read book Explosives Detection Via Stand Off Raman Spectroscopy written by Bernhard Zachhuber and published by Sudwestdeutscher Verlag Fur Hochschulschriften AG. This book was released on 2012-05 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: The increasing worldwide threat of terrorism requires the capability of sytems to remotely detect and identify explosives. A stand-off Raman system was built and optimised which meets these demands including the identification of substances concealed in opaque containers. To meet the challenging situations in real life, explosives and their precursors were analysed in the presence of interfering substances and on a variety of background materials, including plastics or different car doors. The influence of the laser excitation wavelength was also investigated. The stand-off distance was successfully extended to 100 metres at a testing ground at the Austrian Armed Forces. The combination of stand-off Raman with spatial offset Raman scattering has enabled the identification and quantification of substances up to 40 metres in packaging which is non-transparent to the human eye. An alternative way to probe substances inside turbid bottles was found by using depth-resolved stand-off Raman spectroscopy. This methodology employs the speed of light to distinguish between samples located at different distances from the setup.

Download or read book The Application of Stimulated Raman Gain and Inverse Raman Spectroscopy to the Remote Detection of Chemical Agents written by and published by . This book was released on 1987 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of inverse Raman spectroscopy/stimulated Raman gain for the remote detection of chemical agents is analyzed. The sensitivity of this technique is calculated for ranges 1 and 10 kilometers and target cloud widths of 10 and 50 m. The sensitivity is also shown to decrease tremendously as the agent or target cloud moves away from the focal point of the laser.

Download or read book Raman Spectroscopy Volume I written by Günter G. Hoffmann and published by Momentum Press. This book was released on 2019-01-16 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book provides an up-to-date overview of the fast growing area of Raman spectroscopy. The two-volume work describes how analytic methods using Raman spectroscopy allow for the chemical analysis of materials, providing even spatial resolution without precedent. In addition, external perturbations (strain, temperature, pressure) on molecules and their alignment can be analyzed. Raman spectroscopy can also provide information about the interactions of components, again at a high level of spatial resolution. In the form of tip-enhanced Raman spectroscopy (TERS), the method is a valuable tool for nanotechnology. This book is intended for researchers or lecturers in chemistry and materials science, who are interested in the composition and properties of their samples. It describes how Raman spectroscopy will enable them to examine thin layers, surfaces, and interfaces and improve their knowledge about the properties of composites. In addition, it can serve as a short introduction to vibrational spectroscopy.

Download or read book Infrared and Raman Spectroscopy written by Bernhard Schrader and published by Wiley-VCH. This book was released on 1995-03-07 with total page 788 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an excellent introduction to vibrational spectroscopy for scientists in academia and industry. Both infrared and Raman spectroscopy are covered comprehensively and up-to-date. Therefore the book may also be used as a handbook for easy reference. Written in the language of chemists, it explains the basic theory and instrumentation, the interpretation and evaluation of spectra. Furthermore numerous, worked-out examples of practical applications are presented. Therefore the reader is enabled to apply infrared and Raman spectroscopy for solving his own problem and to design suitable experimental procedures. This book also serves as a guide to the relevant literature

Download or read book Surface Enhanced Raman Scattering New Theoretical Approaches Materials and Strategies written by Ivano Alessandri and published by Frontiers Media SA. This book was released on 2020-03-25 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Raman Spectroscopy in Archaeology and Art History written by Howell G. M. Edwards and published by Royal Society of Chemistry. This book was released on 2005 with total page 497 pages. Available in PDF, EPUB and Kindle. Book excerpt: Raman Spectroscopy in Archaeology and Art History highlights the important contributions Raman spectroscopy makes as a non-destructive method for characterising the chemical composition and structure and in determining the provenance and authenticity of objects of archaeological and historical importance. It brings together studies from diverse areas and represents the first dedicated work on the use of this technique in this increasingly important field. Coverage includes: An Introduction to Raman Spectroscopy, including practical aspects of Raman spectroscopy and complementary techniques; Dyes and Pigments; Artefacts; Biological Materials and Degradation; Jewellery and Precious Stones. The book contains a broad selection of real-world examples in the form of case studies to provide the reader with a true appreciation of the procedures that need to be invoked to derive spectroscopic information from some of the most challenging specimens and systems. Colour illustrations of objects of investigation and a database of 72 Raman spectra of relevant minerals are included. With its extensive examples, Raman Spectroscopy in Archaeology and Art History will be of particular interest to specialists in the field, including researchers and scientific/conservation staff in museums. Academics will find it an invaluable reference to the use of Raman spectroscopy.

Download or read book Development Optimization and Characterization of a Surface Enhanced Raman Spectroscopic Method for Detection of Dipicolinic Acid written by Joy D. Guingab and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Surface Enhanced Raman Spectroscopy (SERS) has been explored as a tool to study biological agents. The anthrax distribution in the US postal in October 2001 intensified the need for a rapid and accurate detection of bacterial spores. Dipicolinic acid (DPA) is a unique component of bacterial spores and has been used as a signature molecule for detection schemes. The feasibility of using SERS as a detection technique for bacterial spores is evaluated in this research.

Download or read book Through Barrier Detection Using Surface Enhanced Spatially Offset Raman Spectroscopy written by Fay Nicolson and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Calculated limits of detection suggest that these SERRS nanotags can be detected at concentrations as low as 104 fM using SESORRS.

Download or read book Applications of Raman Spectroscopic Techniques in Forensic and Security Contexts written by Esam Mohamed Abdalla Ali and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Drug trafficking and smuggling is an ongoing challenge for law enforcement agencies. Cocaine smuggling is a high-value pursuit for smugglers and has been attempted using a variety of concealment methods including the use of bottled liquids, canned milk, wax and suspensions in cans of beer. In particular, traffickers have used clothing impregnated with cocaine for smuggling. Handling, transportation or re-packaging of drugs of abuse and explosives will inevitably leave residual material on the clothing and other possessions of the involved persons. The nails and skin of the person may also be contaminated through the handling of these substances. This research study describes the development of Raman spectroscopic techniques for the detection of drugs of abuse and explosives on biomaterials of forensic relevance including undyed natural and synthetic fibres and dyed textile specimens, nail and skin. Confocal Raman microscopy has been developed and evaluated for the detection and identification of particulates of several drugs of abuse and explosives on different substrates. The results show that excellent spectroscopic discrimination can be achieved between single particles and substrate materials, giving a ubiquitous non-destructive approach to the analysis of pico-gram quantities of the drugs and explosives in-situ. Isolating the particle in this way corresponds with an analytical sensitivity comparable with the most sensitive analytical techniques currently available e.g. the highly sensitive, yet destructive ionization desorption mass spectrometry. With the confocal Raman approach, this work demonstrates that definitive molecular-specific information can be achieved within seconds without significant interference from the substrate. The potential for the application of this technique as a rapid preliminary, forensic screening procedure is obvious and attractive to non-specialist operators as it does not involve prior chemical pretreatmentiior detachment of the analyte from the substrate. As a result, evidential materials can be analysed without compromising their integrity for future investigation. Also, the applications of benchtop and portable Raman spectroscopy for the in-situ detection of drugs of abuse in clothing impregnated with the drugs have been demonstrated. Raman spectra were obtained from a set of undyed natural and synthetic fibres and dyed textiles impregnated with these drugs. The spectra were collected using three Raman spectrometers; one benchtop dispersive spectrometer coupled to a fibre-optic probe and two portable spectrometers. High quality spectra of the drugs could be acquired in-situ within seconds and without any sample preparation or alteration of the evidential material. A field-portable Raman spectrometer is a reliable instrument that can be used by emergency response teams to rapidly identify unknown samples. This method lends itself well to further development for the in-situ examination by law enforcement officers of items associated with users, handlers and suppliers of drugs of abuse in the forensics arena. In the last section of this study, a portable prototype Raman spectrometer (DeltaNuAdvantage 1064) equipped with 1064 nm laser excitation has been evaluated for the analysis of drugs of abuse and explosives. The feasibility of the instrument for the analysis of the samples both as neat materials and whilst contained in plastic and glass containers has been investigated. The advantages, disadvantages and the analytical potential in the forensics arena of this instrument have been discussed.