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High Entropy Alloys (HEA) are multi-principal element materials that have been intensively studied over the past decade. In this work, two Al–Fe–Cr–Ni–Cu HEAs were synthesized and processed into thin films by DC magnetron sputtering, and their structural, mechanical and electrochemical properties were systematically evaluated. The coatings exhibited dense, uniform structures with strong adhesion to 304 L stainless steel. Coatings hardness was higher than the substrate material. Electrochemical tests in 3.5 g/L NaCl solution revealed superior corrosion resistance for the I8-10-derived coating, which achieved the lowest corrosion rate (5.54E-05 mm/year) and the highest polarization resistance (5.470.008 Ω), outperforming both the bulk alloys and uncoated substrates.

Materials used in the marine industry are exposed to extreme conditions, so it is necessary to meet remarkable characteristics, such as mechanical resistance, low density, and good corrosion resistance. The challenging environment requires continuous performance improvements, so this work is focused on developing new materials with superior properties, using the electrochemical deposition technique, which are convenient for marine engineering. High-entropy alloys have been attracting tremendous interest in many applications, due to their simple crystal structures and advantageous physical-chemical properties, such as high strength, anti-corrosion, erosion, and electro-magnetic capabilities. To identify the most appropriate compositions, MatCalc software was used to predict the structure and characteristics of the required materials, and thermodynamic and kinetic criteria calculations were performed. The modelling processes generated a series of optimal compositions in the AlCrCuFeNi alloy system, that are suitable to be used in anticorrosive and tribological applications. The composition and morphology of the obtained high entropy alloy thin films revealed a uniform structure, with a small grain profile. The corrosion resistance was investigated in artificial seawater to observe the behavior of the newly developed materials in demanding conditions, and the results showed improved results compared to the copper foil substrate.

The Bi-Sn, Bi-Sn-Ag, and Bi-Sn-Sb solder alloy systems represent lead-free, environmentally friendly alternatives for reliable electronic assembly. These alloys comply with increasingly strict environmental and health regulations, while offering low melting points suitable for soldering temperature-sensitive components. Microstructural analysis revealed distinct phase segregation in all alloys, with Sb promoting coarse Sn2Sb3 intermetallic compounds and Ag inducing fine needle-like Ag3Sn precipitates. Eutectic refinement and compositional contrast were confirmed by SEM-BSE and EDS mapping. Vickers microhardness measurements revealed increased hardness in Sb- and Ag-modified Bi–Sn alloys, with Ag3Sn dispersion yielding the highest strengthening effect, indicating enhanced mechanical potential. This study also reports the thermal and electrical conductivities of Bi60Sn40, Bi60Sn35Ag5, and Bi60Sn35Sb5 alloys over the 25–140 °C range. Bi60Sn40 showed an increase in thermal conductivity across the full temperature range from 16.93 to 26.93 W/m·K, while Bi60Sn35Ag5 reached 18.28 W/m·K at 25 °C, and Bi60Sn35Sb5 exhibited 13.90 W/m·K. These findings underline the critical influence of alloying elements on microstructure, phase stability, and thermophysical behavior, supporting their application in low-temperature soldering technologies.

Protection against microbiologically influenced corrosion (MIC) is critical for materials used in aquatic environments, as MIC accelerates material degradation and leads to faster structural failure. Copper (Cu) has the potential to substantially improve the MIC resistance in alloys. In this study, high-entropy alloy (HEA) coatings containing Cu were deposited using DC (Direct Current) magnetron sputtering to enhance the corrosion resistance and mechanical properties of various substrates. Two CuCrFeMnNi HEA compositions in the form of bulk alloys and PVD (Physical Vapor Deposition) coatings, with 5% and 10% Cu, were analyzed for their microstructural, mechanical, and anticorrosive characteristics. Deposition parameters were varied to select the optimal values. Microstructural evaluations using SEM-EDS (scanning electron microscopy and energy dispersive X-ray spectroscopy), XRD (X-ray diffraction), and AFM (atomic force microscopy) revealed uniform, dense coatings with good adhesion composed of dendritic and interdendritic BCC (body-centered cubic) and FCC (face centered cubic) structures, respectively. Microhardness tests indicated improved mechanical properties for the samples coated with developed HEAs. The coatings exhibited improved corrosion resistance in NaCl solution, the 10% Cu composition displaying the highest polarization resistance and lowest corrosion rate. These findings suggest that Cu-containing HEA coatings are promising candidates for applications requiring enhanced corrosion protection.

This study investigates the application of robocasting technology for fabricating high-density yttria-stabilized zirconia (8YSZ) electrolytes used in solid oxide fuel cells (SOFCs). The primary goal is to overcome the limitations of traditional manufacturing techniques, such as low density and poor microstructural control. Using a combination of hydrothermal synthesis, rheological testing, and robocasting, we achieved dense 8YSZ structures (over 95% density) with minimal porosity. The fabricated electrolytes underwent sintering and debinding processes, with thermal treatment profiles optimized for structural integrity. A microstructural analysis through SEM and XRD confirmed the formation of stable crystalline phase. This research opens new avenues for the use of additive manufacturing in electrochemical applications, particularly for producing complex ceramic components with superior characteristics.

In recent decades there has been an increasing interest in Elliptic curve cryptography (ECC) and, especially, the Elliptic Curve Digital Signature Algorithm (ECDSA) in practice. The rather recent developments of emergent technologies, such as blockchain and the Internet of Things (IoT), have motivated researchers and developers to construct new cryptographic hardware accelerators for ECDSA. Different types of optimizations (either platform dependent or algorithmic) were presented in the literature. In this context, we turn our attention to ECC and propose a new method for generating ECDSA moduli with a predetermined portion that allows one to double the speed of Barrett’s algorithm. Moreover, we take advantage of the advancements in the Artificial Intelligence (AI) field and bring forward an AI-based approach that enhances Schoof’s algorithm for finding the number of points on an elliptic curve in terms of implementation efficiency. Our results represent algorithmic speed-ups exceeding the current paradigm as we are also preoccupied by other particular security environments meeting the needs of governmental organizations.

Lithium lanthanum titanate (LLTO) is a very promising material due to its ability to conduct lithium ions. It has many potential applications in the field of lithium batteries and sensors. Typical synthesis methods include solid-state reaction and sol–gel synthesis. We report a novel solvothermal synthesis method that produces almost single-phase LLTO samples at significantly reduced costs. The samples thus obtained were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), electrical impedance spectroscopy (EIS), and chemical analysis. The results obtained for the newly synthesized samples were compared with results obtained from samples prepared using the solid-state reaction method. The XRD data show the formation of orthorhombic LLTO for the solvothermal synthesis, tetragonal LLTO for the hydrothermal synthesis, and cubic LLTO for the solid-state reaction. Additionally, XRD showed that the solid-state reaction of LLTO is a multi-stage process in which intermediary compounds such as La2Ti2O7 are formed. The bulk ionic conductivity of the LLTO samples produced through the solvothermal and hydrothermal processes is estimated at 10−4 S/cm, and the grain boundary conductivity is estimated at 10−6 S/cm.

The aim of this paper was to investigate the structure and thermal properties of zirconia ceramics co-doped with rare earth (RE) elements in equimolar concentrations. We prepared (1 − x)ZrO2 − x(yLa2O3 + yNd2O3 + ySm2O3 + yGd2O3 + yYb2O3) (x = 0.2; y = 0.2) powders by a hydrothermal method in mild conditions (200 °C, 2 h, 60–100 atm.) The powder was analyzed by XRD, SEM-EDAX, BET, and FT-IR after synthesis and heat treatments at 1200 °C and 1500 °C. The samples exhibit good thermal stability, with a single cubic phase presented after heat treatment at 1500 °C. The compound exhibits a low thermal conductivity (0.61 W·m−1·K−1), a low heat capacity (0.42 J·g−1K−1), and a low thermal diffusivity (0.34 mm2·s−1). The values are lower than reported for conventional RE-doped zirconia.

The combination of ZnO and Fe3O4 nanoparticles represents a synergistic strategy for the treatment of skin cancer, exploiting both oxidative stress-induced cytotoxicity and hyperthermic effects for improved anticancer activity. These nanoparticles also function as drug carriers, facilitating targeted delivery and reducing systemic toxicity. Furthermore, controlled-release systems activated by external stimuli, such as light, pH, temperature, or magnetic fields, optimize the accumulation of the drug in tumor tissues. In the present study, Fe3O4-ZnO composite powders were synthesized in aqueous solution through the hydrothermal method under high pressure and temperature. All synthesized powders were characterized by physicochemical and morpho-structural methods such as: FT-IR, XRD, SEM, DLS, and BET. The influence of the hydrothermal synthesis parameters (pressure and time) on the morpho-structural properties of the magnetite–zinc oxide nanocomposites was studied.

Carbon-based materials are promising candidates for enhancing thermal properties of phase change materials (PCMs) without lowering its energy storage capacity. Nowadays, researchers are trying to find a proper porous structure as PCMs support for thermal energy storage applications. In this context, the main novelty of this paper consists in using a ZnO-CNT-based nanocomposite powder, prepared by an own hydrothermal method at high pressure, to obtain porous 3D printed support structures with embedding capacity of PCMs. The morphology of 3D structures, before and after impregnation with three PCMs inorganic salts (NaNO3, KNO3 and NaNO3:KNO3 mixture (1:1 vol% saturated solution) was investigated by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX). For structure impregnated with nitrates mixture, SEM cross-section morphology suggest that the inorganic salts impregnation started into micropores, continuing with the covering of the 3D structure surface and epitaxial growing of micro/nanostructured crystals, which led to reducing the distance between the structural strands. The variation of melting/crystallization points and associated enthalpies of impregnated PCMs and their stability during five repeated thermal cycles were studied by differential scanning calorimetry (DSC) and simultaneous DSC-thermogravimetry (DSC-TGA). From the second heating-cooling cycle, the 3D structures impregnated with NaNO3 and NaNO3-KNO3 mixture are thermally stable.