الفهرس 
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Abstract
The structure and physical properties of different types of modified vanadium phosphate were studied. The nuclear magnetic resonance spectra of phosphorus and vanadium nuclei were used to clearly identify the structure of the glass network. The experimental studies based on the principle of spinning magnetic resonance showed that, the presence of vanadium oxide in the glass sample results in the formation of many structural units such as:(1) Pyramid coordination, (2) Quadrilateral coordination, (3) Quadrilateral coordination units related to some phosphorus units. On the other hand, when replacing vanadium oxide with modified oxide, the pentagonal groups decrease exponentially and the quadrilateral groups containing many non-bridging oxygen atoms (NBO) increase. This behavior continues until the NBO concentration reaches its maximum end. This behavior leads to the widening of the distances between the layers or annotations of the composition of the glass structure, which increases the capacity and density of electric charge carriers between these layers. Other complementary measurements play an active role in the knowledge and study of the crystalline network and how it is formed as a neatly arranged or random structure. In this regard, measurements were carried out using X-ray diffraction spectroscopy and transmission electron microscopy. FTIR spectroscopy is applied to know the types of functional groups as an integrated unit. Infra-red spectra showed some results that agree well with magnetic resonance results, since the relative area under the spectral curve decreases by increasing the modified oxide at the expense of the glass former oxide of the studied glass. The NMR spectra were all quantitatively analyzed to calculate the concentration of the pentavalent and quaternary vanadium groups in all the glass studied. It was found that the concentrations of quaternary vanadium ions are always increasing at the expense of decreasing the pentavalent concentrations. This behavior is consistent with the characteristics of vanadium as a catalyst, which has been referred to earlier. This behavior depends mainly on the ability of vanadium oxide to produce the non-bonded oxygen atoms that act as oxygen centers, which play a key role in the work of vanadium as a catalyst. The images and results of the transmission electron microscope show that, there are separate synthetic aggregates of different sizes located in the range of 20 to 50 nm. X-ray diffraction and electron diffraction patterns results from electron microscopy measurements were found, however, that this unorganized random structure is transformed into a coordinated, phased arrangement by thermally treating those glasses. The linear change in both the measured density and calculated molar volume with the CdO content are associated with the structural evolution of a regular increase in non-bridging bonds in the glasses as V2O5 is replaced by CdO. It is observed that the density of these glasses increases with the introduction of CdO and associated molar volume is reduced accordingly. This behavior may indicate that the vanadium and phosphate polyhedra form some more open structure due to increasing non bridging bonds with increasing CdO contents. In addition, transformation of both phosphate and vanadate from long chain like structure (high volume) to depolymerized and separate species (lower volumes) is considered. This consideration is correlated to the structural evolution of a frequent increase in non-bridging bonds in the glasses upon substitution of V2O5 with CdO as indicated by both NMR and FTIR measurements.