الفهرس 
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Abstract
Two different groups of glass samples having the general formula:
1) X (Na2O). 0.53 (5102). 0.08 (Bi203). (0.39-X) (B2O3), where
(X = 0.05, 0.15, 0.25, 0.35) for SI, S2, S3 and S4 respectively And, II) 0.25 (Y). 0.53 (SiO2). 0.08 (13i203). 0.14 (B2O3), where Y = Na2O,
K2O and Ag2O for S3, S5 and S6 respectively, were prepared by using conventional method. The I.R and X— ray diffraction were carried out to assure the preparation of the sample in the proper form. Many bands were appeared in the I.R transmission spectra. The obtained data are discussed and reported in the thesis. DSC for three samples was carried out to identify the transition points that are obtained in the
electrical properties.
Seebeck coefficient was measured in the same range of temperature as that of the A.0 conductivity. In order to get information about the type of charge carriers participating in the conduction
mechanism.
The DC conductivity for the investigated samples was measured at an applied electric field as a function of temperature from room temperature up to the crystallization temperature of the sample.
The dielectric constant s’ and A.0 conductivity were also measured in the same range of temperature as the function of the applied frequency. The A.0 conductivity data show that more than one straight the intersecting at the transition temperature were obtained indicating the different conduction mechanism. The values of the obtained activation energy from the experimental data indicate the semi-conducting behavior of the investigated glasses. The measurements of the drift mobility as a function of temperatures at different frequencies indicates that, the hopping mechanism for either electrons or holes and positive polaron are the most predominant one. More than one type of polarization was found to play a role in the dielectric properties of the samples, depending on the temperature region. The calculated values of electric dipole moment proved that, same displacement takes place for the charge carriers with the result of increasing the magnetic moment.
The ion exchange was carried out by immersing the prepared sample in silver nitrate at 623 K. All samples indicating the switching property. The interpretation of this phenomenon could be attained with the electrothermal model to enhance this mechanism.
The 1-V characteristic was carried out by measurement the ion exchange of the samples X (Na20) (0.39-X) (B203) 0.08 (Bi203) 0.53 (SiO2), where (X = 0.05(S1), 0.15(S2), 0.25(S3), 0.35(S4)), at different ambient temperatures (298, 313, 333, 353, 373, 393 K) and different investigated time exchange diffusion (12, 24, 36, 48 h) at 623 K. In addition to vary concentration of sodium as alkali oxide metal glass.
The magnetic susceptibility was carried out using the conve-ntional Gouy’s method at different temperatures as a function of the magnetic field intensity. The magnetic constants were calculated and reported.