Sodium hydroxide autoclaving is the main method for smelting scheelite in China. In this method, sodium phosphate added as an additive to realize highly efficient decomposition of scheelite, and a crude tungstate solution containing obtained. subsequent process ion exchange, phosphorus ions compete with resin adsorption tungstate, which reduces capacity endangers purity solution. To remove from...

The influence of inelastic relaxation time on the intrinsic spin Hall effects in a disordered two-dimensional electron gas with Rashba interaction is studied; we clarify the controversy as regards impurity effects in the system. We reveal that, due to the existence of inelastic scattering, the spin Hall conductivity does not vanish when the impurity concentration diminishes to zero, regardless ...

A nonequilibrium Green’s function method is applied to model high-field quantum transport and electronphonon resonances in semiconductor superlattices. The field-dependent density of states for elastic ~impurity! scattering is found nonperturbatively in an approach which can be applied to both high and low electric fields. I-V curves, and specifically electron-phonon resonances, are calculated ...

When subject to a weak magnetic impurity distribution, the order parameter and quasi-particle energy gap of a weakly disordered bulk s-wave superconductor are suppressed. In the Born scattering limit, recent investigations have shown that ‘optimal fluctuations’ of the random impurity potential can lead to the nucleation of ‘domains’ of localised states within the gap region predicted by the con...

We report the density-functional-theory calculations of the exchange interactions and Curie temperature for a series of III-V and II-VI diluted magnetic semiconductors. We focus the discussion on the role of the holes in the establishing the ferromagnetic order in various systems. We suggest a method of the quantitative characterization of the properties of the holes. It is shown that there are...

Room-temperature tensile experiments on sub-micrometer freestanding thin films deposited at varied base pressures reveal two distinct classes of mechanical response. Samples that contain sufficient impurity concentrations to stabilize the microstructure against an applied stress show strong but brittle response. However, films that were deposited at lower vacuum base pressures that still allow ...

photocatalytic reduction of carbon dioxide to formaldehyde was investigated on four semiconductor photocatalysts (fes, fes/fes2, nio and tio2). the reaction was carried out in continues flow of co2 gas bubbled into the reactor. semiconductor photocatalysts were characterized by x-ray diffraction (xrd) and diffuse reflectance spectroscopic (drs) methods. sulfide ion was used as hole scavenger. t...

We investigated the in-plane resistivity anisotropy for underdoped Ba(Fe(1-x)Co(x))(2)As(2) single crystals with improved quality. We demonstrate that the anisotropy in resistivity in the magnetostructural ordered phase arises from the anisotropy in the residual component which increases in proportion to the Co concentration x. This gives evidence that the anisotropy originates from the impurit...

A one-dimensional system of masses with nearest-neighbor interactions and periodic boundary conditions is used to study mode decay and ergodicity in nonlinear, disordered systems. The system is given an initial periodic displacement, and the total system energy within a specific frequency channel is measured as a function of time. Results indicate that the rate of mode decay at early times incr...

We study a quenched disordered d = 3 tJ Hamiltonian with static vacancies as a model of nonmagnetic impurities in high-Tc materials. Using a position-space renormalization-group approach, we calculate the evolution of the finite-temperature phase diagram with impurity concentration p, and find several features with close experimental parallels: away from half-filling we see the rapid destructio...