A strong interplay between charge, lattice, orbital and spin degrees of freedom exists in transition-metal oxides yielding the emergence of a large spectrum of functionalities such as hightemperature superconductivity, metal/insulator transition, multiferroicity, thermoelectricity... More specifically, mixed valence states of 3d elements issue as a driving force in such interplay. In addition, ...

Cerium–manganese mixed oxides with compositions of Ce0.5Mn0.5O1.75 and Ce0.8Mn0.2O1.9 were prepared by the citric-acid (Pechini) method and their catalytic properties were compared to CeO2 and Mn2O3. The mixed oxides exhibited higher specific rates than either CeO2 or Mn2O3 for oxidation of both methane and nbutane. While XRD measurements of the mixed oxides suggested that the materials had pri...

Silicon carbide grains of type X constitute ~1% of all presolar SiC grains found in primitive meteorites. These grains have N and Si excesses, mostly light C, high inferred Al/Al ratios, and evidence (from Ca and Ti excesses) for the initial presence of the short-lived radioisotopes Ti and V. These isotopic signatures clearly indicate an origin in the ejecta of Type II supernovae (SNe) and mate...

Room-temperature ferromagnetism is observed in (110) oriented ZnO films made from targets containing 5 at. % of Sc, Ti, V, Fe, Co, or Ni, but not Cr, Mn, or Cu ions. There are large moments, 2.6 micro(B) and 0.5 micro(B)/dopant atom for Co- and Ti-containing oxides, respectively. There is also a moment of 0.3 micro(B)/Sc. Magnetization is very anisotropic, with variations of up to a factor of 3...

This study investigated the effects of Ti content and vacuum annealing on the microstructure evolution of TixFeCoNi (x = 0, 0.5, and 1) thin films and the underlying mechanisms. The as-deposited thin film transformed from an FCC (face center cubic) structure at x = 0 into an amorphous structure at x = 1, which can be explained by determining topological instability and a hard ball model. After ...

Composites of the Cu47Ti34Zr11Ni8 bulk metallic glass, reinforced with up to 30 vol % SiC particles are synthesized and characterized. Results based on x-ray diffraction, optical microscopy, scanning Auger microscopy, and differential scanning calorimetry ~DSC! are presented. During processing of the composites, a TiC layer forms around the SiC particles and Si diffuses into the Cu47Ti34Zr11Ni8...

Transition metal oxides are among the most promising solar materials, whose properties rely on the generation, transport and trapping of charge carriers (electrons and holes). Identifying the latter's dynamics at room temperature requires tools that combine elemental and structural sensitivity, with the atomic scale resolution of time (femtoseconds, fs). Here, we use fs Ti K-edge X-ray absorpti...

TiAl with between 0 and 20 volume percent (v%)Ti5Si3 was produced by reactive sintering of cofd pressed compacts of elemental Ti, Al and Si powder mixtures at 7OO0C for 15 minutes in vacuum. The results show that adding Si to Ti and A1 reduces the swelling associated with reactive sintering of TiAI, as composites containing more than 5 vYoTigSi3 densified during reactive sintering. However, com...

Objective. The aim of this study was to assess the influence of implant-abutment interface (IAI) placement depths on peri-implant tissues in the presence of ligature-induced peri-implant inflammation. Materials and Methods. Two implants with screwed-in IAIs (SI) and two implants with tapped-in IAIs (TI) were inserted in one side of the mandible in six dogs eight weeks after tooth extraction. Fo...