Fiber optic gas sensors

In context with methane detection during offshore oil drilling, another infrared fiber optic methane sensor was reported25. The detector comprises 3 main units a microcomputer-based signal processing and control unit, a nonconducting fiber optic gas sensor, and an optical fiber cable module. The system operates at an absorption line of methane where silica fibers have very low losses. 

Mizaikoff B et al (1995) Infrared fiber optic gas sensor for chlorofluorohydrocarbons. Vib Spectrosc 8 103-108... 

Silicones are extremely versatile materials that have found manifold apphcations in optical sensing of chemical species. Their high gas permeability, processability, optical transparency, composition tunabihty, resihency to biofilm adhesion and low cost, together with good chemical and thermal stability, have made silicones one of the polymer materials of choice to immobilize optical indicator dyes at the sensitive layer of fiber-optic gas sensors (mostly for monitoring). Silicones can also be used to manufacture optosensors for nonvolatile species, as long as they are modified with other materials to confer the required permeability to the indicator films. 

Figure 9. Hydrogen response data as a function of time after quenching for gas metal arc welded ASTM A36 steel (0.1% H2/Ar shielding gas) using prototype fiber optic weld sensor.

Figure 11. Experimental hydrogen response curves for prototype fiber optic weld sensor (gas metal arc welded HSLA 100 steel)...

For the evaluation of the SIM technique in chemical sensors application, an experimental set-up was developed as shown in Fig. 31. A fiber-optic chemical sensor was prepared, using polyaniline as the modified cladding for a short MM sensing fiber. The spin-casting method was used for coating a thin layer of polyaniline material on the fiber core surface. Then, the modified fiber was tested for the detection of HCl vapor and NH3 gas. The sensor was tested by both the total intensity modulation and the SIM techniques. 

Chan K, Ito H, Inable H (1984) An optical fiber based gas sensor for remote adsorption measurement of low level methane gas in near infrared region. J Lightwave Technol 2 234—237... 

Pyruvate Corn kernei Pyruvate decarboxyiase CO2 gas sensor, fiber-optic CO2 sensor... 

Miura N (1991) New-type calorimetric gas sensor using temperature characteristics of piezoelectric quartz crystal fitted with noble metal catalyst film. Sens Actuators B 5 211-217 Monz6n-Hemdndez D, Luna-Moreno D, Martfnez-Escobar D (2009) Fast response fiber optic hydrogen sensor based on palladium and gold nano-layers. Sens Actuators B 136 562-566 Mueller WM, Blackledge IP, Libowitz GG (1968) Metal hydrides. Academic, New York, NY Noh J-S, Lee JM, Lee W (2011) Low-dimensional palladium nanostmctures for fast and rehable hydrogen gas detection. Sensors 11 825-851... 

Allen MG (1998) Diode laser absorption sensors for gas-dynamic and combustion flows. Meas Sci Technol 9 545-562 Anderson MS, Andringa JM, Carlson RW, Conrad P, Hartford W, Shafer M, Soto A, Tsapin AI, Dybwad JP, Wadsworth W, Hand K (2005) Fourier transform infrared spectroscopy for Mars science. Rev Sci Instrum 76 034101 Ashizawa H, Yamaguchi S, Endo M, Ohara S, Takahashi M, Nanri K, Fujioka T (2003) Development of a nitrogen dioxide gas sensor based on mid-infrared absorption spectroscopy. Rev Laser Eng 31 151-155 Baldini F, Chester AN, Homola J, Martellucci S (eds) (2006) Optical chemical sensors. Springer, Dordrecht Bansal L (2004) Development of a fiber optic chemical sensor for detection of toxic vapors. Ph.D. thesis, Drexel University, Philadelphia, PA... 

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