We report on the laser damage resistance of ion beam-sputtered oxide materials (Al2O3, Nb2O5, HfO2, SiO2, Ta2O5, ZrO2) and mixtures of Al2O3-SiO2, Nb2O5-SiO2, HfO2-SiO2, Ta2O5-SiO2, and ZrO2-SiO2, irradiated by single 500 fs pulses at 1030 nm. Laser-induced damage threshold (LIDT), refractive index, and bandgaps of the single-layer coatings are measured. For pure oxide materials a linear evolut...

We present gas-phase infrared spectra of tantalum cluster cations containing 6-20 atoms. Infrared multiple photon dissociation of their complexes with argon atoms is used to obtain vibrational spectra in the region between 90 and 305 cm(-1). Many spectra have features in common with the vibrational spectra of the lighter homologs, vanadium and niobium, pointing to a common cluster growth mechan...

We examine a contact between a superconductor whose order parameter changes sign across the Brillioun zone, and an ordinary, uniform-sign superconductor. Within a Ginzburg-Landau-type model, we find that if the barrier between the two superconductors is not too high, the frustration of the Josephson coupling between different portions of the Fermi surface across the contact can lead to surprisi...

The geometry, energetic, and spectroscopic properties of molecular structures of silica-supported niobium oxide catalysts are studied using periodic density functional calculations (DFT) and compared with experimental data. The calculations are done for Nb oxide species inserted or grafted in/on an amorphous hydroxylated silica surface. Different positions of the Nb atom/atoms in the silica str...

Solubility of mixed niobium-titanium carbonitrides in commercially relevant High-Strength Low-Alloy (HSLA) steel was investigated by combined use electrical resistivity measurements and APT after interrupted quenching from soaking temperatures between 950 1250 °C. Increasing the bulk material towards higher proportional to nominal niobium addition which varied 0.002 0.022–0.043–0.085 wt.-%. Cor...

The characteristics of Baiyun Obo niobium-bearing minerals are complex physicochemical properties that make the beneficiation niobium extremely difficult. In this paper, X-ray diffraction, fluorescence and mineral liberation analyzer (MLA) systems were used to study occurrence state distribution in samples from Obo. results show chemical compositions sample complex, with a Nb2O5 grading 0.24%. ...