Monophase and polyphase ceramic materials based on Magneli phases of titanium oxides of composition Ti3O5, Ti4O7, Ti5O9, and Ti6O11 were synthesized. The materials were obtained by mechanical activation of rutile with titanium and additives of niobium, vanadium, and iron, with subsequent sintering both in reductive atmosphere (hydrogen) and in neutral atmosphere (argon) in the temperature interval of 1060-1080°C. The dependences of the potentials of the obtained ceramic samples on time and composition during anodic polarization at current density of 5A/dm2 in a 1M solution of sulfuric acid were investigated. We developed a technique for manufacturing anodes in the form of hollow cylinders 60 mm in diameter with a wall 5 mm thick, and flat discs more than 60 mm in diameter

Co-Ni-Cu/Cu multilayers were electrodeposited directly onto n-doped GaAs substrates with two different crystal orientations, (001) and ( 111), without the use of any seed layer. X-ray diffraction and transmission electron microscopy showed that epitaxial growth occurred on GaAs(001), with either the {001} or {211} planes parallel to the substrate, but not on GaAs(111). On this substrate, the multilayers grow preferentially with the {111} planes parallel to the substrate, but the crystallites have no preferred orientation in-plane. The presence of superlattice satellite peaks in the X-ray data for the multilayers grown on GaAs(001) and their absence for those grown on GaAs(111) indicated that the latter had a less perfect layer structure. Multilayers grown on both substrates exhibited giant magnetoresistance (GMR). For small Cu layer thicknesses, t Cu < 20 Å, the GMR was suppressed for multilayers grown on both substrate orientations. For t Cu between ϳ20 and ϳ30 Å, the GMR was much greater for the multilayers electrodeposited on GaAs(001) than for those on GaAs(111), while for larger layer thicknesses, the GMR for both substrate orientations was similar. This behavior can be explained qualitatively by the presence of different numbers of defects producing different degrees of ferromagnetic coupling in the two sets of multilayers.

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