الفهرس 
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Abstract
An experimental study of some selected fluorescent dyes has been carried out for the development of fluorescence based fiber optic temperature sensor. Fluorescent dyes like: Fluorescein (F) and two of its derivatives [allyl Fluorescein (DA-F) and diallyl Fluorescein (DA-F)] are solidified in glycidyl methacrylate (GMA) polymer matrix. These two Fluorescein derivatives were investigated in order to study the influence of substituted groups on Fluorescein dye sensitivity for temperature changes. The concentration of the dyes in the used polymer is 5x10-3 M. The dye-polymer discs have been investigated separately before being integrated in a fiber optic system in order to determine their sensitivities in the temperature ranges from 10K to 300K and from 297K to 370K. The dye-polymer disc is excited by Argon-ion laser (488 nm, 50 mW) and the fluorescence intensity is measured using lock-in technique. Below room temperature (F) dye in (GMA) polymer shows very weak sensitivity towards temperature changes in the range from 10K up to 297K. The fitting curve therefore gave a polynomial equation of second degree with R2 value of 0.6758. For (AF) dye in (GMA) polymer its fluorescence exhibits temperature tendency for decreasing slightly while the dye is warmed up from 40K to 245K. The calibration curve fits a linear equation with an R2 value of 0.9795. Also, the (DA-F) dye in (GMA) shows good sensitivity in the range from 49K to 300K. Its calibration curve fits with an exponential equation with R2 value of 0.9385. Above room temperature (F) dye in (GMA) polymer showed some sensitivity, in the temperature range from 302K to 370K. The fitting curve gave an exponential equation with an R2 value of 0.8332 therefore the Intensity change/ Temperature change (sensitivity) varies along the exponential line. For application purpose the range of temperature measurement can be divided into two ranges. For the (AF) dye in (GMA) it showed good sensitivity towards temperature changes in the range of temperatures from 301K to 370K. The calibration curve fits an exponential equation with an R2 value of 0.993 therefore the Intensity change/ Temperature change (sensitivity) varies along the exponential line. For application purpose the range of temperature measurement is to be divided into three ranges. Also, the (DA-F) dye in (GMA) showed good sensitivity. The fitting curve gave an exponential equation with R2 value of 0.9825 therefore the Intensity change/ Temperature change (sensitivity) varies along the exponential line. For application purpose the range of temperature measurement can be divided into three ranges. Thermo-gravimetric analysis (TGA) was performed to insure that there is no thermal decomposition happens in the range of temperature measurement for the three dyes in (GMA). Also, photodegradation effect of laser was tested by exposing the samples to laser with continuous light emission for a specific time. Three devices of dye-polymer optical fiber sensors were constructed for the three dyes and tested. The excitation source Argon-ion laser (488 nm and 75 mW). The (F) dye in (GMA) sensor shows good sensitivity. The fitting curve followed a polynomial equation of a second order with R2 value of 0.9907. In the practical use the second order curve is not reliable and the optode device of (F) dye in (GMA) is therefore has poor sensitivity. For the (AF) dye in (GMA) sensor the fitting curve followed an exponential equation with an R2 value of 0.6904. The experimental points are fluctuating along the exponential curve this leads to low Intensity hange/Temperature change (sensitivity). Whereas the (DA-F) dye in (GMA) sensor yielded the closest fit tendency for a linear regression model, with R2 value of 0.99 in the temperature range from 296K to 348K.