Girijavallabhan, C P; Radhakrishnan, P; Nampoori, V P N; Thomas Lee, S; Jose, Gin; Unnikrishnan, N V(Journal of Optics A : Pure and Applied Optics, July 12, 2001)
[+]
[-]
Abstract:
The fabrication and characterization of a fibre optic pH sensor based on
evanescent wave absorption is presented. The unclad portion of a
multi-mode optical fibre is coated with a pH sensitive dye, which is
immobilized by the sol–gel route. The sensitivity of the device has been
found to increase when multiple sol–gel coatings are used as the sensing
region. The dynamic range and the temporal response of the sensor are
investigated for two different dyes, namely bromocresol purple and
bromocresol green. The performance of the device is evaluated in terms of
the results obtained during actual measurements
Radhakrishnan, P; V P N Nampoori; Girijavallabhan, C P; Thomas Lee, S; Jose, Gin; Unnikrishnan, N V(Journal of Optics A: Pure and Applied Optics, July 12, 2001)
[+]
[-]
Abstract:
The fabrication and characterization of a fibre optic pH sensor based on
evanescent wave absorption is presented. The unclad portion of a
multi-mode optical fibre is coated with a pH sensitive dye, which is
immobilized by the sol–gel route. The sensitivity of the device has been
found to increase when multiple sol–gel coatings are used as the sensing
region. The dynamic range and the temporal response of the sensor are
investigated for two different dyes, namely bromocresol purple and
bromocresol green. The performance of the device is evaluated in terms of
the results obtained during actual measurements
V P N Nampoori; Radhakrishnan, P; Girijavallabhan, C P; Thomas Lee, S; Jose, Gin; Unnikrishnan, N V(Journal of Optics A: Pure and Applied Optics, July 12, 2001)
[+]
[-]
Abstract:
The fabrication and characterization of a fibre optic pH sensor based on
evanescent wave absorption is presented. The unclad portion of a
multi-mode optical fibre is coated with a pH sensitive dye, which is
immobilized by the sol–gel route. The sensitivity of the device has been
found to increase when multiple sol–gel coatings are used as the sensing
region. The dynamic range and the temporal response of the sensor are
investigated for two different dyes, namely bromocresol purple and
bromocresol green. The performance of the device is evaluated in terms of
the results obtained during actual measurements.
Sol–gel glasses with Fe3O4 nanoparticles having particle sizes laying in the range 10–20 nm were encapsulated
in the porous network of silica resulting in nanocomposites having both optical and magnetic
properties. Spectroscopic and photoluminescence studies indicated that Fe3O4 nanocrystals are embedded
in the silica matrix with no strong Si–O–Fe bonding. The composites exhibited a blue luminescence. The
optical absorption edge of the composites red shifted with increasing concentration of Fe3O4 in the silica
matrix. There is no obvious shift in the position of the luminescence peak with the concentration of Fe3O4
except that the intensity of the peak is decreased. The unique combinations of magnetic and optical
properties are appealing for magneto–optical applications.
Anantharaman, M R; Senoy, Thomas; Sakthi Kumar, D; Yasuhiko, Yoshida(Springer, December 31, 2006)
[+]
[-]
Abstract:
Sol–gel glasses with Fe3O4 nanoparticles having particle sizes laying in the range 10–20 nm were encapsulated
in the porous network of silica resulting in nanocomposites having both optical and magnetic
properties. Spectroscopic and photoluminescence studies indicated that Fe3O4 nanocrystals are embedded
in the silica matrix with no strong Si–O–Fe bonding. The composites exhibited a blue luminescence. The
optical absorption edge of the composites red shifted with increasing concentration of Fe3O4 in the silica
matrix. There is no obvious shift in the position of the luminescence peak with the concentration of Fe3O4
except that the intensity of the peak is decreased. The unique combinations of magnetic and optical
properties are appealing for magneto–optical applications.
Description:
Journal of Nanoparticle Research (2008) 10:203–206