Environmental optical fibers

Bariain, C Matias, I.R., Fdez-Valdivielso, C Elosiia, C Luquin, A., Garrido, J. and Laguna, M. (2005) Optical fiber sensors based on vapochromic gold complexes for environmental applications. Sensors and Actuators B, 108, 535—541. 

Grattan K.T.V., Meggitt B.T., Optical fiber sensor technology, Vol.4 Chemical and environmental sensing, Kluwer Academic Publishers, 1999, pp. 205-248. 

Orellana G., Moreno-Bondi M.C., From Molecular Engineering of Luminescent Indicators to Environmental Analytical Chemistry in the Field with Fiber-Optic (Bio)sensors, in 15th Optical Fiber Sensors Conference Technical Digest (OFS-2002), IEEE, Piscataway, NJ, 2002 pp. 115-118 (ISBN 0-7803-7289-1). 

Traditionally, UV curable polymers have been utilized as coatings for wood and vinyl floors, but their applications have increased dramatically over the last twenty years to encompass many diverse areas, including optical fiber coatings (7), adhesives (2), disc replications (3-5), and microelectronics (6). This widespread use of UV cross-linked systems is attributed to their rapid, energy efficient curing and their solvent free, one piece formulations. Typically, UV curable systems require only a small fraction of the power normally utilized in thermally cured systems and their solvent free nature offers an environmentally safer alternative. 

Tests for Fire Resistance of Roof Covering Materials, 1983. (similar to ASTM E 108) Tests for Flame Propagation and Smoke Density Values for Electrical and Optical Fiber Cables in Spaces Transporting Environmental Air, 1991. 

It is desirable to have means to measure organohalides such as carbon tetrachloride in situ in water and other environmental media. One approach to doing this has been demonstrated by the in situ analysis of chloroform-contaminated well water using remote fiber fluorimetry (RFF) and fiber optic chemical sensors (FOGS) (Milanovich 1986). With this approach, fluorescence of basic pyridine in the presence of an organohalide (Fujiwara reaction) is measured from a chemical sensor immersed in the water at the end of an optical fiber. Carbon tetrachloride undergoes a Fujiwara reaction, so its determination might be amenable to this approach. 

Cable—An assembly of optical fibers and other material providing mechanical and environmental protection. 

Thus, a poly isobutylene coating on silver halide optical fiber was used for environmental analysis of chlorinated hydrocarbons in water in an instrument designed for operation in seawater 500 m under the surface (Fig. 9.27). The enrichment membrane concept can be used for FTIR-ATR analysis of liquid and gaseous samples alike. 

Bowen, J.M. Sullivan, P.J. Blanche, M.S. Essington, M. Noe, L.J. Optical-Fiber Raman Spectroscopy Used for Remote In-Situ Environmental Analysis US 4,802,761 Assigned to Western Research Institute Filed in 1987. 

IN-LINE OPTICAL FIBER STRUCTURES FOR ENVIRONMENTAL SENSING... 

In-Line Optical Fiber Structures for Environmental Sensing 427... 

Solid-phase microextraction (SPME) is a sampling and concentration technique used to increase the sensitivity of HS methods. This technique is utilized for arson analysis and environmental monitoring purposes and also for clinical and forensic procedures. Short, narrow diameter, fused-silica optical fibers coated with stationary phase polymers are either immersed in the sample or the HS and compounds are adsorbed or absorbed (depending on... 

Optical fibers were originally designed for transmission of information in telecommunication systems for many years. Such fibers have to be protected from interference or the influence of surrounding environmental conditions. 

Holst G, Mizaikoff B (2001) Fiber optic sensors for environmental sensing. In Lopez-Higuera JM (ed) Handbook of optical fiber sensing technology. Wiley, New York, pp 729-749... 

Raman and UV-Vis spectra were recorded on the bisected pellets at several points in time after impregnation. UV-Vis spectra were obtained using a house-built set-up, which is schematically depicted in Fig. 4. The use of optical fibers with different diameter allows one to record a UV-Vis spectrum from a small spot of 50- 100 pm on the sample. Manipulation of the sample can be carried out with great precision with the aid of an automated X-Y-Z-table. The sample is placed in an environmental cell under water-saturated air to prevent dehydration of the wet pellets during measurements. 

Optical fibers offer the unique possibility of performing spectroscopy at the site of interest. In other words, the sample no longer has to come to the spectrometer, but rather the spectrometer goes to the sample. Hence all problems associated with sampling, surface deposition of analyte, delay in analysis, work-up procedures, and decomposition of samples and analytes during the work-up can, in principle, be avoided. It is for these reasons that tremendous expectations are associated with fiber sensor technology in environmental sciences. 

Also for CO sensing, the present sensors are available only for the field of security not for environmental use because of the insufficient sensitivity and selectivity to monitor CO in the atmosphere. Examples of CO sensor which have been improved their sensitivity and selectivity are, for example, SnO semiconductor sensors operated under periodic temperature cycle[85-87], a electrochemical sensor using nafion membrane[88], a catalytic combustion sensor composed of catalysts and hydrophobic pol uner[89], a SnOj diode sensor doped with Pd[90] and an optical fiber catalytic sensor with Au/CogO as combustion catalyst[91]. 

Optical fiber Dye/Polymer matrix Hydrocarbons Environmental monitoring PetroSense... 

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