| In this thesis, preparation and properties of mechanically alloying, solid state reaction, nano materials and technology, rare earth oxides and ferrite materials, especially ceria(CeO2) prepared and applied were reviewed in details. To counter troubles and limits of preparing method of rare earth oxides and ferrite, first united mechanically alloying with solid state reaction use to salt-salt reaction system by means of two step method of preparing precursor and thermal decomposition, relevant the products were obtained. The thermal change, phase, crystallization degree, appearance, size were studied by TG-DTA, XRD, SEM, TEM.We have obtained a lot of high quality nano rare oxides and ferrite. The party data of potical and electromagnetic characteristic paramenter were determined. As a study result of two system reaction mechanism, some important theorelical basis were obtained for confirming "mechnically ball milling salt-salt solid state reaction". About effecting reason of the surface active agent, the templates and the ligand to nano powder appearance. The main crentive results and new progress in this thesis are presented as follows:1.Getting a simple and direct, easy operation, good effect method by united mechanically alloying with solid state chemical reaction, and put to use it in salt-salt system, preparing nano rare earth oxides and ferrites in using market raw materials. Especially, the method have more convenient for preparing precursor at ambient temperature. The stable paramenters of preparing different precursors were obtained . A lot of precursors or mixing precursors of Ce, La, Pr, Nd, Fe, Ni, Zn, Mn, Co ect. Elements were prepared by with H2C2O4·2H2O, NH4HCO3 and 8-hydroxyquinoline (C9ONH9). The"ball milling method" is better compare with "hand milling method". 2. According to mechanism of thermal decomposition, using data of thermal anality (TG-DTA) and controlling appropriate temperature paramenter. One after another obtained CeO2, La2O3, Pr2O3, Nd2O3, Co3O4, γ-Fe2O3, CuO, SnO2, ZnFe2O4, Ni1.5FeCu2.5O5.5, Ce0.25NiFeO3, Ce0.25NiFeO3, (Ni0.5Co0.5)FeO5, Cu0.5Zn0.5FeO5 ect. oxides and compound oxides by decompose their precursors on heatting. The size of these products was in 15-90nm. Their appearance are difference spherical, plate-like, reticulation, short granularity and strips. The method have originality and superiority on preparing nano powder.3. At present, preparation of difference appearance nano powder with the surface active agent, the templates and the ligand , that is one of the important study on nano materials and technology. The varity appearance products were obtained by means of sodium dodecylbenzene sulfonate, ethylene glycol monobutyl ether, templates NaCl, ligand H2C2O4 ·2H2O, NH4HCO3 and 8-hydroxyquinoline ect..4. At present, the study of reaction mechanism for solid state reaction is no more; "mechanical ball milling salt-salt solid state reaction" have no the report. CeO2 and ZnFe2O4 reaction system were selected to study reaction thermodynamics and dynamics. The thermal chemistry paramenters of preparing ZnFe2O4 were determined and counted. The reaction mechanism of preparing CeO2 have step. Preparing precursors Ce2(C2O4)3 ·10H2O have paramenters:ΔHCe2(C2O4)3·10H2O =504.34KJ/mol;ΔSCe2(C2O4)3·10H2O = 2.07KJ/℃?mol; ΔGCe2(C2O4)3·10H2O =-112.52KJ/mol;Ea= 0.342KJ/mol. Thermal decompsition paramenters of Ce2(C2O4)3?10H2O: ΔHCeO2 = 1465.95 KJ/mol,ΔS CeO2 = 3.27KJ/℃?mol, ΔG CeO2= -2044.32KJ/mol, Ea。'=4.96KJ/mol. This shows, the preparing reaction and the thermal decomposition reaction of Ce2(C2O4)3 ·10H2O are all endothermic reaction, and can completed quikly, spontaneously.5.The characteristics of some nano powder was studied:Polishing and opital characteristics of nanometer CeO2 was studied: ①The temperature may effect polishing property at thermal decomposition , CeO2 active will reduce bring about impair polishing results when excessive temperature; ②Nano CeO2 have good absorbable characteristics for ultraviolet ray (21...
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