Crystal Research and Technology最新文献

This study employs molecular dynamics (MD) simulations to investigate the mechanical properties of the $��C�r�F�e�M�n�N�i�$ high entropy alloy (HEA) with grain boundaries Σ5 and Σ13, as well as the structure without GBs and edge dislocations. To evaluate size-dependent effects, models of increasing dimensions (initial, four times larger, 9th times larger) were examined. The outcomes of our study reveal that the variation in atomic sizes among constituent elements causes lattice distortion, leading to deformation in HEAs. GB Σ5 exhibited increased strength and hardness, as evidenced by Young's modulus of 271.86 GPa, bulk modulus of 177.17 GPa, and shear modulus of 109.25 GPa, all higher than those of the non-GB system. In contrast, GB Σ13 demonstrated superior ductility, with Cauchy's pressure of 52.64 GPa, Poisson's and Pugh's ratios of 0.311 and 2.31, respectively, based on the initial model. The mechanical properties of HEA were seen to be greatly affected by the grain boundaries, which in turn influenced the ductility. Additionally, the study highlights that the inclusion of edge dislocations and grain boundaries significantly improves the yield strength of the $��C�r�F�e�M�n�N�i�$ HEA boosts its overall mechanical performance. This study reveals how grain boundaries affect HEAs' mechanics, highlighting GB engineering and dislocations for stronger, high-performance materials design.

BaGa₂GeSe₆ crystal is a promising material for mid- to far-infrared frequency conversion. The synthesis of phase-pure polycrystalline BaGa₂GeSe₆ is crucial for growing high-quality single crystals. In this paper, the transportation and reaction properties of the dual-zone synthesis of BaGa₂GeSe₆ polycrystalline materials were investigated. The quenching technique was employed to identify major reaction intermediates, which PXRD analysis revealed to be α-BaGa₂Se₄. The dual-zone synthesis is used to eliminate GeSe₂ escape, and selenium vapor transported from the low-temperature zone reacts with Ba, Ga, and Ge in the high-temperature zone (1203 K) to form pure BaGa₂GeSe₆, as confirmed by XRD. Using this phase-pure polycrystalline material with extra GeSe₂, a large single crystal of BaGa₂GeSe₆ with the dimensions of 24 mm in diameter and 60 mm in length was successfully grown by the vertical Bridgman method. A sample sized 6 × 6 × 10 mm³ was fabricated from the as-grown crystal. The as-grown BGGSe crystal exhibited a narrow FWHM of 39.60'' and broad optical transmittance.

BaGa₂GeSe₆ crystal is a promising material for mid- to far-infrared frequency conversion. The synthesis of phase-pure polycrystalline BaGa₂GeSe₆ is crucial for growing high-quality single crystals. In this paper, the transportation and reaction properties of the dual-zone synthesis of BaGa₂GeSe₆ polycrystalline materials were investigated. The quenching technique was employed to identify major reaction intermediates, which PXRD analysis revealed to be α-BaGa₂Se₄. The dual-zone synthesis is used to eliminate GeSe₂ escape, and selenium vapor transported from the low-temperature zone reacts with Ba, Ga, and Ge in the high-temperature zone (1203 K) to form pure BaGa₂GeSe₆, as confirmed by XRD. Using this phase-pure polycrystalline material with extra GeSe₂, a large single crystal of BaGa₂GeSe₆ with the dimensions of 24 mm in diameter and 60 mm in length was successfully grown by the vertical Bridgman method. A sample sized 6 × 6 × 10 mm³ was fabricated from the as-grown crystal. The as-grown BGGSe crystal exhibited a narrow FWHM of 39.60'' and broad optical transmittance.

In this study, we report the microwave-assisted synthesis of morphology-controlled cupric oxide (CuO) nanostructures using ethylenediaminetetraacetic acid (EDTA) and polyethylene glycol (PEG) as morphology-controlling agents. The structural, morphological, and optical properties of the prepared CuO nanostructures are thoroughly investigated using XRD, FTIR, FESEM, EDX, PL, and UV–vis spectroscopy. XRD analysis revealed the development of monoclinic CuO with different crystallinity. FESEM analysis showed that the CuO synthesized in the absence of an organic modifier exhibited a flake-like nanostructure, whereas the use of PEG and EDTA as morphology controllers resulted in the formation of spherical and rod-like nanostructures, respectively. The photocatalytic test was conducted on eosin yellow dye degradation using the synthesized CuO nanostructures under visible light for 120 min. The shape-dependent photocatalytic degradation of eosin yellow dye by the synthesized CuO nanostructures was observed with the respective degradation efficiencies of 81.70%, 95.50%, and 98.13% for flake-like, spherical, and rod-like nanostructures. Hence, morphology-controlled synthesis plays a key role in optimizing the photocatalytic performance of CuO nanostructures, making them more effective for environmental remediation.

Pharmaceutical cocrystals are emerging as a promising strategy to modify the physicochemical properties of the API (Active Pharmaceutical Ingredient). Solvent-based cocrystallization techniques involve the use of a large quantity of organic solvent and energy consumption, making continuous manufacturing challenging. The current research aimed to manufacture Fluconazole cocrystals via a mechanochemical process. The kilogram scale batch of fluconazole (FLZ) and para-hydroxy benzoic acid (PHBA) cocrystals is prepared using neat grinding and liquid-assisted grinding. Results suggested liquid-assisted grinding to be the ideal cocrystallization technique, where complete cocrystals are developed within 90 min of processing time. The FLZ-PHBA CC showed good flow characteristics with improved compressibility, tabletability, and compactibility properties. The Cocrystals showed a reduced elastic recovery rate, which is favourable for powder compression. The Heckel and Kawakita analysis of FLZ-PHBA cocrystals resulted in reduced P_k and P_y, depicting more plastic deformation and particle rearrangement. Moreover, the cocrystal presented better hygroscopic and accelerated stability than FLZ alone. The in vivo pharmacokinetic parameters of FLZ, FLZ-BA CC, and FLZ-PHBA CC are studied in Wistar rats. The study revealed that after cocrystallization, no significant change is observed in the pharmacokinetic parameters of FLZ.