الفهرس 
Chapter 1 : Introduction and Object of InvestigationOnly 14 pages are availabe for public view
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Abstract
This thesis presents and discusses the results of the synthesis and characterization of some rare earth metal oxides (Sm203 Th02 and Gd203) and some transition m’etal oxides (Nb20s, Fe203 and a-Mn203)’ To accomplish this objective, a joint study of thermal analysis, IR spectroscopy, X-ray diffraction and measurements of nitrogen and water vapour adsorption isotherms have been carried out. Nitrogen adsorption has been determined using the volumetric technique at -196°C. whereas, the adsorption isotherms of water vapour have been determined gravimetrically at 30°C.
Motivated by the above characteristic advantageous (Introduction (Chapter I)) we choosed these oxides (rare earth and transition metal oxides) for comparison proposes. Texture assessment (surface area and porosity) was carried out via an:alysis of nitrogen adsorption isotherms at (-196°C) adopting BET-, t- methods and pore size distribution curves (PSDs). Thermal behaviour of parent oxide precursors of niobium nitrate, iron hydroxide, manganese nitrate, samarium acetylacetonate, gadolinium acetate and thorium nitrate were explored by thermogravimetry (TG) and differential thermal analysis (DT A). Accordingly, the calcination products of the oxides were obtained at the appropriate temperatures. The final oxide materials were characterized by XXray difractometry (XRD) and the chemical identity of metal-oxygen species by IR spectroscopy.