Sreekumar, K(Optical society of America, June 20, 2004)
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Abstract:
A methylene-blue-sensitized polymer blend of polyvinyl alcohol and polyacrylic acid is fabricated and
tested for holographic recording. It was found to have good characteristics such as high sensitivity,
storage stability, ease of fabrication, and environmental stability. Optimization of the ratio of polyvinyl
alcohol polyacrylic acid, the sensitizer concentration, pH, energy, diffraction efficiency measurements,
etc., have been done. pH is found to have a great influence on the recovery of the dye in this matrix.
The results of experimental investigations into the properties of this new material are reported.
Remalakshmy,Poduval; Girish Kumar,K(Department of applied chemistry, 2006)
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Abstract:
In this study Fabrication of Potentiometric sensors for the determination of certain metal ions, presents the synthesis and characterization of seven ionophores, their use in the fabrication of potentiometric sensors and the results and discussion of fourteen sensors developed for the determination of five transition metal ions. As part of the present investigations a total of fourteen potentiometric sensors have been developed and fabricated. A three fold approach has been taken in developing he sensors, PVC plasticized membrane sensor, carbon paste electrode and chemically modified carbon paste electrode. All the sensors are highly useful in the determination of metal ions such as manganese, nickel, copper, mercury and lead. A through analytical study has been carried out with respect to each other developed. Based on these studies, optimum conditions have been developed for the quantitative determinations of the selected metal ions using the sensors. Systematic application studies have also been carried out for all the developed sensors and the results revealed that the presently developed sensors are far superior than most of the sensors reported.
Bijumon, P V; Dr.Sebastian, M T; Mohanan, P(Regional Research Laboratory (CSIR), August , 2005)
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Abstract:
This thesis presents the microwave dielectric properties of two novel dielectric
resonator materials with the composition Ca(Ca1/4Nb2/4Ti1/4)O3 and Ca(Ca1/4Ta2/4Ti1/4)O3
ceramics and their application in the fabrication of wideband antennas. The microwave
dielectric properties of the ceramics were tailored by several techniques such as doping,
glass addition and solid solution formations in the complex perovskite A and B-sites with
suitable substitutions. Among the wide variety of DRs developed, ceramic resonators
with optimum properties were identified to fabricate broadband dielectric resonator
loaded microstrip patch antennas. Furthermore, wideband, high permittivity dielectric
resonator antennas were fabricated and explored the possibility of tuning their
characteristics by modifying the feed line geometries.