Remote LIBS

Sharma S, Misra A, Lucey P et al (2007) Combined remote LIBS and Raman spectroscopy of sulfur-containing minerals, and minerals coated with hematite and covered with basaltic dust at 8.6 m. Spectrochim Acta A 68 1036-1045... 

LIBS standoff mineralogical applications have been previously considered and it was proved that effective information may be obtained remotely (Cremers and Radziemski 2006 Sharma et al. 2003 Palanco and Lasema 2004 Salle et al. 2007). To prove such possibility in real life scenario. Laser Distance Spectrometry (LDS) constructed and successfully tested in real field conditions a remote LIBS (ReLIBS)... 

The LIBS technique has found application in several different areas. Metals, semiconductors, ceramics, polymers, and pharmaceuticals have been analyzed by LIBS. In addition to solid samples, gaseous and liquid samples can be used, in fact, the first applieaiions of LIBS were for the remote analyses of hazardous gases in industrial environments. Various process litj-uids, biological solutions, aqueous environmental solutions. and pharmaceutical preparations have also been analyzed... 

LIBS has been also successfully applied to the analysis of geochemical samples [1485]. The most accurate information can be obtained for the relative concentrations of different elements in a sample. This is important, for example, for the classification of minerals on earth or in meteroites when it is not clear whether two different samples come from the same source. Also for archeological samples the precise knowledge of elemental composition is very helpful for the exact dating and assignment. The applications of LIBS has benefitted from the use of fiber optics which allows remote sensing, where the laser and detection systems are far away... 

Remote (standoff) LIBS systems have been built by Applied Photonics Ltd. with a range capability of >100 m for defense departments. They also built a transportable standoff LIBS with a 20 m range to characterize radioactive materials in a hot cell at the Sellafield, UK, high-level nuclear waste vitrification plant by directing the laser beam through the lead-glass window of the cell. LIBS is an excellent tool for remote and in situ detection of uranium oxide fuel located in hard-to-reach... 

A relative newcomer to the atomic emission instruments commercially available, LIBS has some significant advantages over the other emission techniques and over ICP-MS and XRF. It is virtually nondestructive and often can be used with no sample preparation. It has the ability to detect all of the elements in virtually any sample type. Versions are available that are field-portable, and versions are available for remote/standoff analysis. Instrumentation is relatively inexpensive. The major disadvantage is the lack of LIBS spectral libraries for easy fingerprint matching, but that is being remedied as the instrumentation becomes more common. 

The methods most widely in use now for understanding and monitoring chemical processes that affect our environment and the atmosphere are those of TDLAS, and remote absorption/Raman spectroscopy based on lidar (absoiption-Hdar/ Raman-lidar). Application examples of these two techniques are outlined in Sections 28.1—28.3 and Sections 28.4-28.6 respectively. The chapter will conclude with the description of some less-developed techniques, which, however, provide information not easily obtained, or not accessible at all. All of them are based on ionization in one form or other, and include laser-induced breakdown spectroscopy (LIBS), matrix-assisted laser desorption ionization (MALDl) and aerosol TOFMS (ATOFMS). Examples of these are provided in Section 28.7. 

Figure 28.30 Examples of LIBS spectra spectra are normalized to the strongest line in the traces. Prominent elemental lines are indicated, (a) Brick sample, submerged under water. Experimental parameters optical fibre remote set-up ( 10 m distance) laser pulse energy 10 m3 observation delay time 3 ps. Adapted from Beddows et at, Spectrochim. Acta B, 2002, 57, with permission of Elsevier, (b) Aqueous solution of 1000 ppm technetium (Tc) in water. Experimental parameters telescopic remote set-up ( 5 m distance) laser pulse energy 30 mJ observation delay time 5 ps. Reproduced from Samek et at, Opt Eng., 2000, 39 2248, with permission of the International Society for Optical Engineering, (c) Stack emission at RKIS incinerator facility Cd hits n = 24) and corresponding ensemble-averaged spectrum n — 600) the two traces are shifted for clarity. Adapted from Buckley et at. Waste Manage., 2000, 20 455, with permission of Elsevier...

LIBS demonstrated a great capacity for accurate analysis of samples of various compositions, even for in-situ sampling of soils that may exhibit surface dust accumulation. LIBS remote sensing capabilities also make this method an attractive option for a variety of soils analysis and agronomic applications. The ability to obtain immediate results from analyses allows for on-site evaluation of contaminants or pollutants, which can be particularly useful for environmental and... 

Classical and novel laser ablation arrangements with ICP-MS detection have made mapping biological (and botanical) tissues a revolutionary and high-resolution tool in medical research. Laser ablation s older cousin, laser-induced breakdown spectroscopy (LIBS), has reached the ultimate remote measurement on Mars and is expected to visit Venus in the next decade. 

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