Raman remote sensing

Mostafa Ahangrani and Torsten Gogolla. 1999. Spontaneous Raman Scattering in Optical Fibers with Modulated Temperature Raman Remote Sensing. Journal of Light wave Technology 17 1378 1391. 

The use of optical fibers has been another technological advance that has created new applications for RS [25,123-125]. Raman remote sensing via optical fibers allows for measurements to be made in harsh and hostile environments (e.g., radioactive sites or high-temperature reactors) or where samples are difficult to access (probes with total diameters less than 1 mm are available). Moreover, sample alignment requirements are reduced, sample perturbation is minimal, and samples can be at large distances from the spectrometer (up to several hundred of meters [126-128]). Also, due to the ability to easily move the probe from one site to another without moving the spectrometer workstation, experimental setup times are minimized. 

The FT-Raman remote sensing probe was used to discriminate ivory specimens [405]. FT-Raman should not be used to study catalysts, carbons and emulsion polymerisation, where D-Raman can provide very useful spectra. 

Alarie J.P., Stokes D.L., Sutherland W.S., Edwards A.C., Vo-Dinh T., Intensified charge coupled device-based fiberoptic monitor for rapid remote surface-enhanced Raman-scattering sensing, Appl. Spectrosc. 1992 46 1608-1612. 

The Applications of Laser-induced Time-resolved Spectroscopic Techniques chapter starts with a short description of laser-induced spectroscopies, which may be used in combination with laser-induced luminescence, namely Breakdown, Raman and Second Harmonic Generation. The chapter contains several examples of the application of laser-based spectroscopies in remote sensing and radiometric sorting of minerals. The proljlem of minerals as geomaterials for radioactive waste storage is also considered. 

Remote sensing - [NONDESTRUCTIVE EVALUATION] (Vol 17) -by infrared spectroscopy [SPECTROSCOPY, OPTICAL] (Vol 22) -infrared technology for [INFRARED TECHNOLOGY AND RAMAN SPECTROSCOPY - INFRARED TECHNOLOGY] (Vol 14) -by Raman spectroscopy [INFRARED TECHNOLOGY AND RAMAN SPECTROSCOPY - RAMAN SPECTROSCOPY] (Vol 14)... 

Satellites - [ALUMINUMAND ALUMINUM ALLOYS] (Vol 2) -batteries for [BATTERIES - SECOND ARYCELLS - ALKALINE] (Vol 3) -hydrazine fuel for [HYDRAZINE AND ITS DERIVATIVES] (Vol 13) -infrared remote sensing from [INFRARED TECHNOLOGY AND RAMAN SPECTROSCOPY - INFRAREDTECHNOLOGY] (Vol 14) -synthetic quartz crystals for [SILICA - SYNTHETIC QUARTZ CRYSTALS] (Vol 21) -thermoelectric power supplies for [THERMOELECTRIC ENERGY CONVERSION] (Vol 23)... 

Raman spectroscopy has its main strength in the combination of a fairly high chemical selectivity and a true remote sensing capability. In comparison, NIR has been used extensively in the manufacturing industry due to its ruggedness and simplicity with respect to interfacing of probes to process vessels. However, due to fairly poor spectral selectivity it has to be paired with multivariate data evaluation and is thus sometimes considered as a black box technique. Mid-IR, on the other hand, offers a high selectivity and is also well established... 

Philbrick C.R. (2002). Overview of Raman lidar techniques for air pollution measurements in lidar remote sensing for industry and environmental monitoring. SPIE Proceedings, 4484, 136-150. 

G. R. Abell and C. E. Gillespie, Remote Sensing and Analyzing of Gaseous Materials Using Raman Radiation, US Patent 3625613 19680628 (1971). 

Whitley, A. and Barnett, S. Advances and useful applications of Raman spectroscopy, imaging, and remote sensing. SPIE 3261 250-259,1998. 

As for Raman and mid-IR spectroscopy, advances in data manipulation and the availability of chemometric analytical software have greatly assisted extraction of useful information from near-IR spectra. This is particularly important for NIR spectra because they are difficult to interpret in terms of chemical structure. An additional technical advance, fiber optics, has allowed the acquisition of NIR spectra by remote sensing. 

Quantitative and qualitative analyses of inorganic and organic compounds can be performed by Raman spectroscopy. Raman spectroscopy is used for bulk material characterization, online process analysis, remote sensing, microscopic analysis, and chemical... 

As noted earlier, fused silica optical fiber is used for remote NIR measurements. The same type of fiber optic probe can be used for Raman spectroscopy, and enables remote measurement of samples and online process measurements. In situ reaction monitoring by Raman spectroscopy has been used to study catalytic hydrogenation, emulsion polymerization, and reaction mechanisms. Remote sensing of molecules in the atmosphere can be performed by Raman scattering measurements using pulsed lasers. 

Enhanced Raman Detection using Spray-On Nanoparticles/Remote Sensed Raman Speetroseopy... 

One consequence of this dependence of particular significance to remote sensing of aerosols is that it would be a mistake to assume that any fluorescent or Raman signals are simply proportional to the number of active molecules contained in the particle. 

The various techniques of Raman scattering that enable laser-based diagnostics of technical combustion processes as well as species identification on the micrometer scale or remote sensing of molecular species and pollutant in the atmosphere. 

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