Near infrared fibers

M. Daneshvar, G. A. Casay, M. Lipowska, G. Patonay, and L. Strekowski, Investigation of a near-infrared fiber-optic immunosensor, SPIE—The International Society for Optical Engineering Chemical, Biochemical, and Environmental Fiber Sensors V 2063, 128-138(1993). 

DE2 DeRosa, M.E., DeRosa, R.L., Noni, L.M., and Hendrick, E.S., Phase separation of poly(A-isopropylacrylamide) solutions and gels using a near infrared fiber laser, J. Appl. Polym. Sci., 105, 2083, 2007. 

In principle, Raman spectroscopy is a microtechnique [161) since, for a given light flux of a laser source, the flux of Raman radiation is inversely proportional to the diameter of the laser-beam focus at the sample, i.e., an optimized Raman sample is a microsample. However, Raman microspectroscopy able to obtain spatially resolved vibrational spectra to ca. 1 pm spatial resolution and using a conventional optical microscope system has only recently been more widely appreciated. For Raman microspectroscopy both conventional [162] and FT-Raman spectrometers [ 163], [ 164] are employed, the latter being coupled by near-infrared fiber optics to the microscope. 

Chan K., Ito H., Inaba H., Humio H., Remote sensing system for near-infrared differential absorption of methane gas using low-loss optical fiber link. Appl. Optics 1984 23 3415. 

Inaba H., Chan K., Ito H., All-optical remote gas sensor system over a 20 km range based on low-loss optical fibers in the near infrared region, Proc. SPIE-Int. Soc. Opt. Eng. 1984 514 211. 

The pH measurement can by realized using sol-gel films and evanescent-wave sensors method74. To incorporate a near-infrared pH sensitive fluorescent dye, a thin-film coating on the core of a multimode fiber was used. By evanescent wave excitation an absorption or fluorescent based sensor can be realized for use in high pH regions. 

Miniaturized chemical analysis systems have been developed for most macroscopic counterparts (Dittrich et al. 2006). The availability of optical fibers, light sources, and detectors in the visible UV and near-infrared (NIR) wavelengths makes it possible to integrate spectroscopic measurements in microreactors (Lobbecke et al. 2005). Fourier transform infrared spectroscopy (FTIR) is an efficient, broadly applicable... 

Fiber glass-reinforced plastic tanks, 24 299 Fiber grating, 11 150-151 Fiber length (FL), 18 148 Fiber manufacture, sodium bisulfite in, 23 673 Fiber-matrix bonding, 26 771-772 Fiber modification, chemical, 16 14 Fibernodes, 11 595 Fiber-optic probes, 16 524 Fiber optics, 11 128-162, 15 469 attenuation in, 11 132-133 dispersion in, 11 134-135 fiber drawing in, 11 141-145 fiber strength in, 11 141-145 history of, 11 128-131 inside processes for, 11 136-140 near-infrared, 23 141 optical amplifiers with, 11 145-146 optical fiber fabrication for,... 

Infrared spectra, of fats and oils, 10 823 Infrared spectral region, 19 564 Infrared spectroscopy, 14 224-243 23 136-143. See also Chromatography-infrared spectroscopy Far- infrared spectroscopy ir-selective surfaces Ir (infrared) spectroscopy Near- infrared spectroscopy Thermal analysis-infrared spectroscopy applications of, 14 239-240 23 140-141 in composition measurements, 20 682 in fiber optic fabrication, 11 138 industrial applications of, 14 240 instrumentation in, 14 225-228 23 137-138... 

T. Okazaki, T. Imasaka, and N. Ishibashi, Optical-fiber sensor based on the second-harmonic emission of a near-infrared semiconductor laser as light source, Anal Chim Acta 209, 327-331 (1988). 

Simply stated, fiber-optic cable allows for the transfer of light from one point to another withont going in a straight line, and as such their use in process analytical apphcations is highly seductive. In a likely near-infrared process application there may be multiple sample stream take-offs, each with different sample characteristics, located in positions spread around a process unit, with the only apparently convenient analyzer location some distance away. 

C. Coffey, A. Predoehl, D.S. Walker, Dryer effluent monitoring in a chemical pilot plant via fiber-optic near-infrared spectroscopy, Appl. Spectrosc., 52(5), 717-724 (1998). 

S.C. Harris and D.S. Walker, Quantitative real-time monitoring of dryer effluent using fiber optic near-infrared spectroscopy, J. Pharm. Sci., 89(9), 1180-1186 (2000). 

S.2.2.2 ICLS Example 2 This example discusses the determination of sodium hydroxide (caustic) concentration in an aqueous sample containing sodium hydroxide and a salt using NIR spearoscopy. An example of this problem in a chemical process occurs in process scrubbers where CO, is converted to Na,CO and H,S is converted to Na,S in the presence of caustic. Although caustic and salts have no distinct bands in the NIR, it has been demonstrated that they perturb the shape of the water bands (Watson and Baughman, 1984 Phelan et al., 1989)-Near-infrared spectroscopy is therefore a viable measurement technique. This method also has ad tages as an analytical technique for process analysis because of the stability of the instrumentation and the ability to use fiber-optic probes to multiplex tlie interferometers and Icx ate them rcm< >tely from the processes. 

Petrov, G. L, Yakovlev, V. V., and Minkovski, N. I. 2003. Near-infrared continuum generation of femtosecond and picosecond pulses in doped optical fibers. Appl. Phys. B 77 219-25. 

Gift, A. D., Ma, J., Haber, K. S., McClain, B. L., and Ben-Amotz, D. (1999), Near-infrared Raman imaging microscope based on fiber-bundle image compression, J. Raman Spectrosc., 30,757-765. 

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