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In this paper, we used the first-principles method to investigate the structural, electronic, mechanical and thermodynamic parameters of the ternary $\beta$-Ti–15Nb–xSi alloys with $x=0.6,0.8,1,1.2,1.4,1.6$wt.%. We have carried out theoretical computations inside the density functional theory (DFT) utilizing the generalized gradient approximation (GGA) with the Perdew–Burke–Ernzerhof (PBE) model. The random distribution of Nb atoms in the alloy was described by using both virtual crystal approximation (VCA), special quasirandom structure (SQS) and the coherent potential approximation (CPA) techniques, in combination with first-principles plane-wave pseudopotential (PW-PP) and exact muffin-tin orbital (EMTO) methods. We determined the elastic constants as well as the bulk, shear, Young’s modulus and Poisson’s ratio. Our structural results are in good agreement with the available experimental and theoretical results for the pure structure of the titanium. In addition, we have estimated the band structure and the density of state (DOS) for the electronic computations. Our findings demonstrate that all of the compounds are metallic, stable and meet the requirements for stability. Young’s modulus of Ti–15Nb–0.6Si and Ti–15Nb–1.6Si is 86.5GPa and 15.11GPa, respectively, which are similar to Young’s moduli of human bone (10–30GPa). All calculated parameters of the alloys decreased with increasing of Si concentration except for Poisson’s ratio, anisotropy and B/G ratio. Furthermore, all of the materials investigated showed ductile nature, and Young’s modulus values are needed for further applications. Excitations from the quasi-harmonic Debye approximation’s vibrational part were applied to the 0K free energy calculated via ab-initio calculations. The influence of temperatures up to 800 K on phase stability was investigated. These findings can be utilized to help designers create alternative low-modulus alloys for biomedical applications.

This study began by preparing gallium oxide (Ga₂O₃) doped with zinc fluoride (ZnF₂) and manufacturing a target material. Subsequently, electron beam (e-beam) deposition was employed to coat silicon substrates with the prepared material. Different heat treatment conditions were applied to the deposited films, followed by material and electrical property analyses. The investigation explored the impact of pre-sintering Ga₂O₃ at 950°C to transform it into a more stable $\beta$-phase. For comparative purposes, some samples underwent annealing at 600°C in a nitrogen–hydrogen (95% N${}_2+5\%$ H₂, abbreviated as N${}_2+{\mathrm{\text{H}}}_2$) mixed gas, which was used as a reduction atmosphere, to increase oxygen vacancies in the ZnF₂-doped Ga₂O₃ thin films and consequently enhance their conductivity. The deposited ZnF₂-doped Ga₂O₃ thin films initially exhibited an amorphous phase, with diffraction peaks appearing only after a 600°C annealing process. Pre-sintering Ga₂O₃ powder at 950°C promoted the emergence of the $\beta$-phase, and the bandgap value increased after annealing. Measurements using B1500A revealed that sintering and annealing ZnF₂-doped Ga₂O₃ thin films were essential steps to enhance their conductivity. X-ray photoelectron spectroscopy (XPS) further confirmed a significant correlation between the conductivity variation and the concentration of oxygen vacancies. Additionally, it was observed that the use of an N${}_2+{\mathrm{\text{H}}}_2$ mixed gas further increased the presence of oxygen vacancies in the films. The results of this study provide an important method to make Ga₂O₃ thin films with conductivity, which can be utilized in the fabrication of Ga₂O₃ thin-film-based semiconductor devices in the future.

The Poly(vinylidene) fluoride (PVDF) thin films with a high content of β-phase were prepared by controlling heat-treatment temperature using casting from the poled solvents. The crystallite microstructure of thin films was depicted by the techniques of X-ray diffraction and FTIR. The results showed that heat treatment was favorable for inducing the β- and γ-phase formation of PVDF. The β phase films were obtained with heat treatment at temperatures ranging from 60°C to 120°C and annealing at 120°C after casting from DMF. The thermo-optical effect of β phase PVDF films was investigated using a spectroscopic ellipsometer. At temperatures ranging from 20°C to 100°C, the refractive index of PVDF was negatively correlated with the temperature between 350 and 1500 nm. The value of the t.o. coefficient of PVDF films was calculated at all temperatures. The maximum value of the t.o. coefficient was about 3.3 × 10^-4/°C at the ascending stage of temperature and 3.0 × 10^-4/°C at the descending stage of temperature. Therefore, it is possible to use the thermo-optic effect of the β phase PVDF for long wavelength infrared imaging.

A simple and effective electrochemical deposition method to fabricate lead oxide micro-octahedrons is reported. Unlike previous reports in which the current densities of electrochemical deposition were normally not more than 5 mA/cm² and resulted in the deposition of lead flakes, the current densities in our process were improved to more than 15 mA/cm² which results in the deposition of lead oxide micro-octahedrons. Our results indicated that well-shaped lead oxide micro-octahedrons could form at current densities in the range of 15–25 mA/cm².