Ta2O5 nanoparticles have been synthesized from alkoxy carboxylates of tantalum via the sol-gel route. Tantalum alkoxides were reacted with chlorocarboxylic acids in order to lower the susceptibility hydrolysis. When these modified alkoxy carboxylates were used in the sol-gel synthesis, they yielded Ta2O5 nanoparticles of better properties than those of the alkoxide-derived Ta2O5 nanoparticles. ...

In sheet metal forming (SMF), the major failure reason is galling. Galling is a process of different wear stages that leads to destruction of both the forming tool and the sheet metal working piece and is, because of that, of big economic importance for the SMF industries. Therefore, investigations and researches about how tool steels microstructure affect the tool steels galling resistance is ...

The mass absorption coefficients of tungsten and tantalum were measured with soft x-ray photons from 1450 eV to 2350 eV using an undulator source. This region includes the M3, M4, and M5 absorption edges. X-ray absorption fine structure was calculated within a real-space multiple scattering formalism; the predicted structure was observed for tungsten and to a lesser degree tantalum as well. Sep...

A series of niobium and tantalum imido complexes with mono-anionic ortho-metallated acetophenone imine ligands have been prepared and characterized using NMR spectroscopy, mass spectrometry and elemental analysis. These low symmetry complexes are produced with only one or two structural isomers in all cases and display interesting correlations between the steric bulk of the ligands employed and...

A waveguide laser in an ytterbium-doped tantalum pentoxide film is reported. The waveguide is formed of a rib of sputtered tantalum pentoxide on top of oxidized silicon with an over-cladding of silica. Emission at a wavelength of 1025 nm was achieved with an absorbed pump power threshold and slope efficiency of ≈29  mW and 27%, respectively, for a cavity formed by a high reflector mirror and an...

The ESR in a tantalum capacitor is a culmination of the resistivities associated with the contact of each capacitive element within the capacitor structure. The basis of the structure is an extremely porous pellet of pressed tantalum particles that are sintered in a vacuum to enhance the contact areas between these particles. The cathode contact is the deposited MnO2 material, which snakes thro...

Amorphous tantalum oxide thin films were deposited by reactive rf magnetron sputtering onto @001# silicon substrates. Growth temperature, oxygen partial pressure, and total gas pressure have been varied to obtain thin films with different densities. The thin films were analyzed by glancing angle-of-incidence x-ray diffraction, atomic force microscopy, and variable angle-of-incidence spectroscop...

OBJECTIVES the aim of this study was to evaluate the surgical technique and determine the initial results, with a minimum follow-up of two years, from total knee arthroplasty revisions in which trabecular metal cones made of tantalum were used at the Knee Surgery Center of the National Institute of Traumatology and Orthopedics (INTO) or at the authors' private clinic between July 2008 and Decem...