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YAG powders and coatings were developed for the first time by a novel precursor plasma spraying technique using the radio frequency (RF) induction plasma technique. The XRD of the as -sprayed coating confirms the presence of YAG, H-YAP or O-YAP or a mixture of the above depending on the spray conditions. 27Al MAS NMR of the YAG coating corroborates the x-ray results. TEM studies on the coatings confirm that the coating consists of nano-structured particles. The successful spraying of these complex oxide coatings proves that chemistry of phase formation can be controlled in the plasma, thus opening up new avenues in material synthesis.

Future application is presented for ultra- and nanodispersed powders in the technology of simple and complex oxide ceramics. Ceramic materials based on these powders are considered relating to different functional classes, their properties, features of their preparation and fields of application are described in detail. The development of ceramic materials with high operating properties will make it possible to resolve important scientific and technical problems connected with developing new technology

The influence of alloying elements on oxidation behavior of TiAl has been investigated using an ion-implantation technique and the mechanisms were discussed. The influence can be classified into several groups according to their effects. The implantation of β-forming elements, halogens, Cu and Zn results in a significant improvement of the oxidation behavior through formation of Al 2 O 3 layer in the initial stage of oxidation. The improvement by Zn is attributed to the formation of complex oxide of Zn and selective oxidation of Al beneath the layer. The implantation of Al , Si or P is also effective. On the other hand, implantation of Ag , Se and other several elements enhance the oxidation. The deterioration by Ag or Se is explained in terms of Al depletion in the implanted layer.

The wet oxidation of various organic compounds was carried out in the presence of the Co–Bi (5:1) complex oxide catalyst. The catalyst was especially effective for the oxidation of all refractory lower carboxylic acids, which are intermediates in the wet oxidation of many organic compounds.

Present works report the luminescent properties of M 2 YSbO 6 :R 3+ (M=Ba, Ca; R=Sm, Dy, Ho, Er, Tm). Ca 2 YSbO are found to be the effective host for activators such as Sm 3+ , Dy 3+ , Ho 3+ , Er 3+ . The R 3+6 emission depends strongly on the structure of the complex oxide. The dependence of the yellow-to-blue intensity ratio of the Dy 3+ luminescence on the concentration of Dy 3+ is discussed.

Ferroelectric behaviour in polycrystalline BaTiO3 films with thicknesses down to 100 ± 20 A has been found. PS for films 100 to 5000 A is 2 to 10 μC/cm2. Vacuum deposits of solid solutions (Ba,Sr)TiO3 in the range 1000 to 3000 A have been grown with different Curie points. Studies have been carried out on films of some new complex oxide structure ferroelectrics.

Dielectric characteristics of several complex-oxide compounds have been investigated. The materials investigated are those with rutile- or rutile-like crystal structure, and the complex-oxides related to TiO2. Some candidates for microwave resonator materials are shown.

The cation distribution in W3Nb14O44, determined by time-of-flight, powder diffraction on a pulsed neutron source, is found to be consistent with the site potentials calculated using an electrostatic model.