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Complex oxides La 0. 9 7 Ba 0. 0 3 MnO3, La 0. 7 3 Ba 0. 2 7 MnO3 and La 0. 5 Ba 0. 5 MnO3 were synthesized and their structural properties were studied. The structural investigation of the samples is done by incorporating X-ray diffraction (XRD) and scanning electron microscope (SEM) technique at room temperature. The Rietveld method was successfully used for the analysis of the obtained diffraction spectra. It was determined that these compounds have a perovskite structure. Partial substitutions La→Ba do not disturb the ideal perovskite structure and the cubic crystal structure with the space group Pm-3m is preserved. Crystallographic parameters, lattice parameters and interatomic distances were determined for each compound. As a result of SEM studies, it was determined that the size of crystallites in LaxBa 1 − x MnO3 solid solutions ranged from 2 to 10 μ m. [ABSTRACT FROM AUTHOR]

The current study demonstrates the effect of Ni-substitution on the structural, dielectric and ferroelectric properties of Ba0.90Sr0.10Ti1-xNixO3 (where x = 0.000, 0.005, 0.015 and 0.025) ceramics, synthesized by solid-state reaction approach. A pure perovskite phase with tetragonal structure has been confirmed by X-ray diffraction (XRD) analysis. Scanning electron microscope (SEM) images revealed change in microstructure. The dielectric behavior of the prepared ceramics was investigated as a function of temperature (30–150°C) at different frequencies. The results indicate that there is an increase in dielectric constant (ϵRT) and low dielectric loss (tanδRT) were obtained at room temperature by substitution of Ni2+ ions in BST ceramics, offering a promising material for capacitor applications at room temperature. Room temperature P-E loops were recorded at different applied electric fields and typical hysteresis loops were obtained. Improvement in the values of Pr and Pmax was observed by substitution of Ni2+ ions. [ABSTRACT FROM AUTHOR]

The economic spray pyrolysis process were used to prepare Zinc oxide thin films. Ahigh - quality thin film is obtained by optimizing factors that include concentration, flow rate, nozzle to substrate distance. The temperature is differed between 350°C to 450°C. The structural and optical qualities were studied through physical investigation. According to XRD, the films have a hexagonal crystal structure. A scanning electron microscope reveals the material's uniform deposition &adhesion across a glass substrate. A direct band gap of about 2.4 to 2.6 eV was obtained for different temperatures. [ABSTRACT FROM AUTHOR]

The aim of the present work was to evaluate six commercially available abutment screws by characterising roughness parameters, microstructure and mechanical properties. Six abutment screws from each implant system, were used. The surface roughness parameters (S a , S q , S sk , S ku , S pk , S k and S vk) were identified by an optical interferometric profiler. Microstructural observations and crystallographic analysis were performed using a scanning electron microscope (SEM) equipped with an energy dispersive X-ray spectroscopy (EDX) device for elemental analysis and an X-ray diffractometer (XRD), respectively. The Martens Hardness (HM), Indentation Modulus (E IT), elastic index (η IT) and Vickers hardness (HV) of all specimens were determined by instrumented indentation testing (IIT). The results were analyzed by one-way ANOVA and Tukey multiple-comparison tests (a=0.05). EDX and XRD showed the abutment screws to be mixed α- and β-phase titanium alloys. Microstructural analysis revealed a fine homogeneous microstructure without porosity, consisting of fine dispersoid rods of β-phase embedded in a continuous α-phase matrix. Statistically significant differences were found among the mechanical properies and surface roughness parameters apart from S q , S pk and S vk. The tested abutment screws showed significant differences in the probed properties, and, thus, differences in their clinical behaviour are anticipated. [ABSTRACT FROM AUTHOR]

Despite numerous studies focused on the hydrothermal (HT) synthesis of fly ash zeolites (FAZs), this method still has many limitations, the main of which is the low yield of zeolites. Hydrothermally synthesized zeolites are typically multiphase and exhibit low purity, which limits their applicability. Pure-phase zeolites have been primarily prepared from filtrates after alkaline mineralization of fly ashes, not directly in suspension. In addition, the published methodologies have not been tested in a wider set of samples, and thus their reproducibility is not confirmed. The aim of the study is to propose a reproducible methodology that overcomes the mentioned limitations. The influence of the Si/Al ratio (1.3:1–1:2), the type and concentration of the activator (2/4 M NaOH/KOH/LiOH), the reagent (30% LiCl), the duration (24–168 h), and the temperature (50–180 °C) of the synthesis phases were studied. The sequence of the synthesis phases was also optimized, depending on the type of heat transfer. The fly ashes were analyzed by wavelength-dispersive X-ray fluorescence (WD XRF), flame atomic absorption spectrometry (F-AAS), and X-ray diffraction (XRD). The energy intensity of the synthesis was reduced through the application of unique microwave digestion technology. Both microwave and combined (microwave and convection) syntheses were conducted. FAZs were identified and quantified by XRD analysis. This study presents a three-stage (TS) hydrothermal synthesis of pure-phase sodalite in suspension. Sodalite (>99 wt.%) was prepared from nine fly ashes under the following conditions: I. microwave phase: 120 °C, 150 min, solid-to-liquid ratio (S/L) 1:5, Si/Al ratio 1:1.5, and 4 M NaOH; II. convection phase: 120 °C, 24 h, S/L 1:40, and the addition of 30 mL of 30% LiCl; and III. crystallization: 70 °C for 24 h. The formation of rhombododecahedral sodalite crystals was confirmed by scanning electron microscope (SEM) images. [ABSTRACT FROM AUTHOR]

Magnesium alloys have become suitable candidates for potential biomedical materials due to their excellent mechanical properties, biocompatibility, and biodegradability. Among different Mg alloys, the Mg–Zn–Ca system is the most popular degradable implant material. The aim of this work is the structure and thermal investigation of the ternary Mg66Zn30Ca4 alloy by a high-energy ball milling process for 5, 8, 13, and 20 h. Morphology changes (SEM) and phase analysis (XRD) of searching materials were investigated. The morphology of the obtained powders and the chemical composition were examined using a scanning electron microscope (SEM) with the energy-dispersive spectrometer (EDS). The distribution of powder size of the samples was determined using the laser particle size analyzer. The thermal characteristics of the powders have been investigated up to 450 °C by differential scanning calorimetry (DSC). Additionally, a microhardness test was carried out. The XRD diffraction patterns of powders show the presence of a solid solution of αMg and the Mg51Zn20 phase. The characteristic Bragg lines of unreacted Zn and Ca can be observed in addition. The DSC analyses showed phase transformations taking place in the alloy. SEM analysis showed a lamellar morphology, which is the result of the deformation process within milling. The results of the microhardness (HV0.05) measuring showed that increasing the milling time improved the microhardness of the Mg66Zn30Ca4 alloy. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the structure, physical properties, and antifungal activity of ZnTe single-layer, ZnTe/Cu/ZnTe (ZCZ), and ZnTe/Ag/ZnTe (ZAZ) multilayer films. The ZAZ multilayer had the greatest antifungal efficacy, with ZCZ and ZnTe following in descending order of effectiveness. We observed that ZCZ had a MIC of 0.30 mol/ML and that ZAZ had a MIC of 20 mol/L. An X-ray diffraction (XRD) test confirmed a cubic crystal structure for all films, indicating that the crystals were mainly arranged along the (111) plane. For ZnTe films, the average size of crystallites was estimated to be roughly 15 nm, while for ZAZ and ZCZ films, it remained relatively constant at around 14.2 nm and 14.1 nm, respectively. We determined the particle size of ZnTe, ZCZ, and ZAZ using a scanning electron microscope (SEM) and ImageJ analysis. The obtained sizes were 98 nm, 200 nm, and 81 nm for ZnTe, ZCZ, and ZAZ, respectively. We used Swanepoel method and the Cauchy equation to determine the refractive index (n), film thickness (d), and refractive index as a function of wavelength. We used the Tauc equation to find that the optical band gaps (E g) of the films were 1.67 eV for ZnTe, 1.5 eV for ZCZ, and 1.55 eV for ZAZ. We analyzed six new frequency bands found through FTIR analysis. These bands showed important information about the chemical structure of the films. [Display omitted] • ZAZ films have superior antifungal activity. • The Ag middle layer boosts ZAZ composite efficacy. • Enhanced understanding of ZnTe multilayer's antifungal properties. [ABSTRACT FROM AUTHOR]