The Studies On The Synthesis And Characterization Of Magnetic Nanocomposites And Its Effect On The Biocatalytic Properties Of Metalloporphyrins

In this thesis, Fe₃O₄ nanoparticles were synthesized by chemical common precipitation method. After a series of experiments, the different factors that affected the chemical common precipitation synthesis were investigated and the appropriate conditions of chemical common precipitation synthesis were confirmed. And using tetraethylorthosilicate (TEOS) as a precursor of silica, Fe₃O₄ nanocomposites uniformly coated in silica matrix(F/S) were successfully synthesized by using microemulsion method. The effect of working condition on the synthesis of the F/S nanocomposites by the microemulsion method was also studied. We find that the ratio of the reactants was important to the composition of the nanocomposites. For example, the volume of H2O and TEOS in W/O microemulsion would affect the diameter and the appearance of the F/S nanocomposites. The best ratio of the reactants was found by carrying a series of experiments. In addition the characterization and discussion of samples prepared were carried out. The magnetic properties and the appearance of the samples were studied in detail. As a result, the relation between the saturated magnetization and the appearance of samples was also discussed.Furthermore, chemical common precipitation method was used respectively to make the substitute experiments. Then nanometer magnetic spinel compound oxides (ZnFe2O4,CoFe2O4,NiFe2O4,CuFe2O4,MnFe2O4) were prepared and them were uniformly coated in silica matrix(X/S) by using the same method noted in the paper before. The characterization and discussion of samples prepared were carried out. The magnetic properties and appearance of samples were studied in detail.In addition, we founded the model of metalloporphyrins catalyzing PHIO to oxide of cyclohexane in order to simulate Cytochrome P-450 monoxygenase catalyzed hydroxylation of hydrocarbon in the living organisms by using the magnetic nanocomposites as a resource of magnetic field. It may be helpful to uncover some phenomena that are very important to the living organisms.Then magnetic nanoparticles materials were of broad application in so many fields, the investigations of those materials were of universal significance. Studying the effects of the magnetic nanoparticles materials on the catalytic properties of metalloporphyrins is also very important. It can discovery the process of forming life in the living organisms and make us understanding and applying our earth which we lived on better.