A methodology accounting for the contributions of static displacements of atoms to X-ray diffuse scattering by binary solid solutions with a face-centered cubic lattice was proposed. By microscopic accounting of static displacements of the atoms on the particular shell, we identified short- range order parameters on the first eight shells of Ni-13.1at. %W alloy from the intensity of X-ray diffuse scattering. The Fourier transform of static displacement of the atoms on every considered shell was calculated with the De Launay model using expressions of elements of dynamical matrix and Fourier transforms of quasi elastic forces, which are calculated by the pseudopotential method.

High entropy alloys (HEAs), or concentrated solid solution alloys, are chemically complex metallic solid solutions in which five or more elements occupy the same crystallographic lattice sites with nearly equal compositions. The high degree of chemical disorder gives rise to considerable local lattice distortions, atomic-level stresses, and complex electronic structure, resulting in interesting properties. We calculated the electronic structure and the atomic-level stresses of AlxTiyZryPdyCuyNiy, x = 0.5, y = 1 (Al0.5TiZrPdCuNi) HEA in the glassy phase using the density functional theory (DFT) approach. We also briefly discuss the electronic structure in its crystalline phase. Whereas it has been reported recently that the crystalline phase of this HEA is obtained as a metastable phase during the crystallization of a glassy phase, the crystalline phase was found to be unstable at T = 0 in the DFT calculation. For this reason, we focus mainly on the glassy phase in this work. The importance of charge transfer among elements on the atomic-level pressure and the role for atomic-level stresses to characterize the electronic and structural heterogeneity are discussed.

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Submicron-sized calcium carbonate (CaCO3) particles were prepared using an aerosol method in which two commercial air humidifiers containing 0.05 M of Na2CO3 and CaCl2 aqueous solutions were utilized as aerosol suppliers. Two streams of aerosols evaporated from the separate humidifiers were allowed to meet in 17-meter long, spiral reaction tube where collisions between two types of droplets containing precursor reagents leaded to grow of CaCO3 particles and precipitate onto the inner walls. XRD and SEM analysis revealed that CaCO3 particles were formed in calcite phase almost entirely.

For disordered binary solid solutions, a new method is proposed for calculating the ordering energies in an arbitrary coordination sphere, taking into account the linear size effect. Using the model potential of transition metals, the Animalu calculated the ordering energies of the Ni-14at.% Pt solid solution in twelve coordination spheres. The temperature of the order-disorder phase transition was estimated for the Ni-14at.%Pt alloy. Satisfactory agreement with the experimental data is obtained.