الفهرس 
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Abstract
This work is aimed to use the advantages of 29Si, 27Al, 23Na, and 11B NMR as a sensitive powerful tool to give specific correlation between structure and properties of sodium borosilicate glasses. We devoted our trials to study the microstructural properties of these glasses in terms of glass composition. In addition, the magnetic properties of iron oxide containing glasses has to be studied. The present results showed that the substitution of B2O3 by iron oxide brings changes in the structure and properties be havior of the resulting glass. Modern solid-state nuclear magnetic resonance (NMR) methodologies are applied to investigate two spin -5/2 nuclei (11B and 27Al) as well as half spin 29Si nuclei in different coordination environments. High resolution (12.3T) MAS NMR is applied in order to characterize the material structure which may be depended on the electric field gradient (EFG) and nuclear magnetic shielding of these nuclei. The advantages of using high MAS NMR technique were appeared in detecting 29Si, 27Al and 11B spectra directly at ambient temperatures. As a result, successful investigations of the different boron, aluminum and silicon sites in more complex glass system containing iron oxide were simply carried out. In all investigated glasses, the high-field 27Al, 11B and 29Si NMR spectra are analyzed and dominated by chemical shift interaction. Solid-state 27Al NMR experiments are employed to determine the composition and number of aluminum distinct sites in these borosilicate glasses. It is evidenced that aluminum oxide as a glass former species AlO4 is the main formed type in glass of Al2O3/SiO2 <1. In this situation, AlO4 is coordinated with silicate units only. On the other hand, at higher Al2O3/SiO2 ratio, AlO4 are coordinated with both silicate and borate specie In this thesis, we have followed the structure changes in the network of the quaternary borosilicate glasses by using additional structural techniques. XRD and EDP spectroscopy are carried out to differentiate between different range ordered species upon Fe2O3 additions. TEM and SEM were used to study the morphological changes as a result of changing glass composition. The local environments of iron, their clustering behaviors and their dependence on glass compositions have been obtained. It is concluded that replacement of boron by iron is accompanied with strong effects on crystallization and clustering behaviors. The tendency of Fe toward crystallization and clustering is much higher in glasses enriched with nonbrdging bonds as is evidenced from NMR data. These phases are confirmed to be present at specific low concentrations from iron oxide. In general SEM, X-ray diffraction, EDX pattern and FTIR spectra of the iron containing glasses revealed the presence of nanostructure of iron silicate and sodium silicate species. The type of crystalline silicate phases are found to have some direct effects on some material properties. In this regard, magnetic behavior of the glasses is found to be affected by presence of iron oxide in silicate clustered phases.