The results covered by the research program have deepened the basic knowledge and were the subject of two doctoral thesis and two master degrees. The research report covers most prospective results, which are of a key importance for the science by itself and have, however, also a technical value. This can be justified by the fact that the results were published in high-ranking journals with the highest impact factor for this research area, i.e. J. Am. Cer. Soc; (1/25), besides some results were also patented. We have shown that a detrimental anomalous grain growth can be circumvented when the grain growth process in MnZn-ferrites is planed in advance by applying a retarded solution-reprecipitation process. This phenomena is of a general importance for all systems where a liquid phase is associated with a sintering process. The segregation of cations on the grain boundaries is associated with the presence of ferrous ions. This process takes place in the grain boundary of a thickness of about 10 nm where a relative large concentration gradient of ferrous ions is present. This process is governed by the nearness of the grain surface where special conditions influence the solid state chemistry of the intrinsic grain boundary. This finding holds more or less for all iron containing oxide based ceramic magnetic materials. The results showed that beside the classical cation - donors occupying the lattice sites also the anion-donors can be applied in order to modify the semi conducting properties of the barium titantes, as for instance fluorine on oxygen sites. The doped material with donors on oxygen lattice sites can have a very low room temperature electric resisitivity, what is important for the production of commercial posistors.