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The sol-gel approach prepared Sr-doped BiFeO3 samples using citric acid as fuel. The structure, lattice dynamics, magnetization, and dielectric properties have all been studied using various techniques, including the LCR meter for dielectric analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and vibrating sample magnetometer (VSM). X-ray diffraction (XRD) analysis of powdered Sr-doped BiFeO3 shows the formation of a pure BiFeO3 rhombohedral structure of the perovskite-type. The FESEM micrograph shows the morphology of the pallets of the samples unaffected by Sr doping at low concentrations. Vibrational modes surrounding the Fe–O–Fe stretching bonds are briefly described by FTIR spectra in transmittance mode. Moreover, it has been found that at room temperature, the dielectric constant and dielectric loss tangent of the samples, evaluated in the frequency range of 100–107 Hz, decrease significantly. The magnetic investigation results indicate that the saturation magnetization is slightly enhanced with an increased concentration of Sr2+. The pristine BiFeO3 had the lowest remanent magnetization value. The ions' saturation magnetization and remanence magnetization values reached 1.85 emu/g and 0.88 emu/g, respectively, at x = 0.25. [ABSTRACT FROM AUTHOR]

In daily routine movement, the ankle joint plays a crucial role in stability and mobility, especially when different types of terrain are involved. However, the simple task of standing can become a biomechanical difficulty when performed on a slope since demands that have to be accommodated are made on the complex structure of the ankle joint. The purpose of this study is to develop finite element (FE) models of the ankle joint with different inclined foot postures and to analyse the stress distributions on the ankle joint while standing on an inclined or declined surface. In this study, the FE model of the foot was developed, and von Mises stress distribution at the ankle joint was explored. The results show that the bone, cartilage, and ligament of the ankle experienced a different von Mises stress distribution pattern during flat standing in comparison with slope standing. In addition, this study found that the maximum von Mises stress distribution at the component of the ankle joint is higher during slope standing than flat standing. Taken together, these results suggest that slope standing, both inclined and declined, with more than 10° inclination, might contribute to a higher risk of injury as a higher maximum stress was observed. Therefore, to maintain proper body posture, it is suggested that weight be evenly distributed at both feet, since this can reduce stress at the ankle. [ABSTRACT FROM AUTHOR]

Surgeons face a significant challenge due to the heat generated during drilling, as excessive temperatures at the bone–tool interface can lead to irreversible damage to the regenerative soft tissue and result in thermal osteonecrosis. While previous studies have explored the use of machine learning to predict the temperature rise during bone drilling, this in vitro study introduces a comprehensive approach by combining the Response Surface Methodology (RSM) with advanced machine learning techniques. The main objective lies in the comprehensive evaluation and comparison of support vector machine (SVM) and random forest (RF) models specifically for the optimization of the bone drilling parameters to prevent thermal bone necrosis. A total of 27 experiments were conducted using a multi-level factorial method, with analysis performed via the Minitab software version 19.1. Performance metrics such as the mean squared error (MSE), mean absolute percentage error (MAPE), and coefficient of determination (R2) were used to assess model accuracy. The RF model emerged as the most effective, with R2 values of 94.2% for testing and 97.3% for training data, significantly outperforming other models in predicting temperature fluctuations. This study demonstrates the superior predictive capabilities of the RF model and offers a robust framework for the optimization of surgical procedures to mitigate the risk of thermal damage. [ABSTRACT FROM AUTHOR]

The sol–gel auto-combustion process synthesized materials with Mg2+ and Ce3+-substituted CoFe2O4 nano ferrites. The research focuses on the nanoparticles, specifically Co1−xMgxFe2−yCeyO4 (where x = 0.0, 0.25, 0.5, and 0.75; y = 0.0, 0.03, 0.06, and 0.09) (CMC) ferrite nanomaterials characterizations utilizing techniques such as XRD, FESEM with EDS, FTIR, electrical analysis, and VSM. The X-ray powder diffraction (XRD) patterns indicate the formation of a spinel structure, with no distinct peaks for rare earth ions, likely due to their minimal doping. Increasing the ionic sizes of RE3+ ions decreases the lattice parameter of the resulting nanoferrites. Field emission scanning electron microscopy (FESEM) shows the samples are aggregated and nearly spherical. At the same time, energy-dispersive X-ray spectroscopy (EDS) confirms the presence of Co, Mg, Ce, Fe, and O. Fourier-transform infrared spectroscopy (FTIR) absorption bands predict the range of spinel ferrites, indicating that RE3+ ions replace Fe3+ ions in the B sites. DC electrical resistivity decreases with the concentration of substituted ions. Dielectric properties, including the dielectric constant, dielectric loss, and AC conductivity, were studied using LCR meters across various frequencies. AC conductivity increases with frequency while both the dielectric constant and loss decrease. These observations align with the Maxwell–Wagner polarization theory. The magnetic properties of CMC nanoparticles, such as squareness ratio (SQR = Mr/Ms), coercivity, saturation magnetization, remanence, and magnetic moment, were determined and analyzed using the vibrating sample magnetometer (VSM). [ABSTRACT FROM AUTHOR]

In the present investigation, aluminum metal matrix composites (AMMs) reinforced with aluminum nitride (AlN) nanoparticulates at different volumetric ratios of (0, 0.5, 1, 1.5, and 2 vol.%) were manufactured via a microwave-assisted powder metallurgy technique. The morphological, physical, mechanical, and electrochemical properties of the produced billets were examined to reflect the impact of the successive addition of AlN into the aluminum (Al) matrix. The morphological analysis revealed the high crystalline patterns of the formation of the Al-AlN composites. The microstructural analysis confirmed the presence of the elemental constituents of Al and AlN particles in the fabricated composites, showing an enhanced degree of agglomeration in conjunction with the additional amount of AlN. Positive behavior exhibited by the micro- and nanohardness was noticeable in the Al-AlN composites, especially at the ultimate concentration of AlN in the Al matrix of a 2 vol.%, where it reached 669.4 ± 28.1 MPa and 659.1 ± 11 MPa compared to the pure Al metal at 441.2 ± 20 MPa and 437.5 ± 11 MPa, respectively. A declining trend in the compressive strength was recorded in the reinforced Al samples. The corrosion resistance of the AlN-reinforced Al metal matrix was estimated at 3.5 wt.% NaCl using electrochemical impedance spectroscopy and potentiodynamic polarization. The results reveal that the inclusion of 2.0 vol.%AlN led to the lowest corrosion rate. [ABSTRACT FROM AUTHOR]

MoO3 thin film was fabricated on an indium tin oxide substrate using the physical vapor deposition technique. X‐ray diffraction and scanning electron microscopy study to investigate surface morphology, grain size, and surface structure, which are critical for absorbing solar spectra in water splitting for hydrogen energy generation. Ultraviolet–visible spectroscopy was used to confirm the absorption of solar spectra and the percentage of transmittance. Fourier‐transform infrared analysis provided the functional groups present in the deposited thin film. The Tauc plot was used to determine the thin‐film band gap, which allowed for the analysis of charge carrier transitions from the conduction band to the valence band. Electrochemical impedance spectroscopy investigations confirmed the charge transfer processes to the counter electrode and electrolyte interfaces. The observed low curve for MoO3 indicated low resistance and allowed efficient charge transfer. Linear sweep voltammetry analysis was used to measure photocurrent and solar light to hydrogen emission when the thin film was exposed to solar spectra. The thin film's observed hydrogen emission rate was 3731.74 mol g−1 h−1, and the STH% of MoO3 was found to be 0.345% at 0.8 V. These findings highlight the promising potential of MoO3 as a material for hydrogen energy generation using solar light. [ABSTRACT FROM AUTHOR]

The quest for lightweight, high-performance structural materials for demanding applications such as in the fields of automotive, aerospace, and other high-tech and military industries pushes the boundaries of material science. The present work aims to draw attention to a novel, sustainable manufacturing approach for the development of next-generation 7xxx series aluminum alloys that have higher strength by rejuvenating a sustainable compositional and thermomechanical processing strategy. Our innovative strategy integrates two key synergies: trace hafnium (Hf) addition for microstructural refinement, unique thermomechanical treatment involving cryorolling, and a short annealing method. Experimental results revealed that our base alloy exhibited a 33 µm grain size and impressive initial mechanical properties (334 MPa UTS, 150 HV). Adding 0.6 wt.% Hf and employing 50% cryorolling with short annealing led to a remarkable 10 µm grain size reduction and significant mechanical property leaps. The resulting alloy boasts a 452 MPa UTS and 174 HV, showcasing the synergistic advantageous effect of Hf and cryorolling plus annealing treatment. The developed alloys were compositional- and work hardening-dependent, leading to a rich mix of strengthening mechanisms. Optical and scanning electron microscopy reveal several intermetallic phases within the fcc matrix, wherein the Al3Hf phase plays a key role in strengthening by impeding dislocation movement. In addition to experimental results, a 12-full-factorial design experiment via ANOVA analysis was also utilized to validate the significant influence of Hf and cryorolling on properties with (p-values < 0.05). Among the different parameters, cryorolling plus annealing appeared as the most noteworthy factor, followed by the composition. Using the regression model, the ultimate tensile strength and hardness were predicted to be 626 MPa UTS and 192 HV for an alloy with 0.6 wt.% Hf and 85% cryorolling, which opens a new avenue for ultra-high-strength Al7xxx alloys. [ABSTRACT FROM AUTHOR]

In the process of solar photovoltaic, ferroelectric semiconductors such as BiFeO3 are found to be new class of materials as an alternative to traditional semiconductors for more energy generations. The efficient chare transformation as well as the enhanced optical absorbance are the key factors for better performance of these ferroelectric semiconductors, which can be facilitated by depositing plasmonic Au nanoparticles on the surface of BiFeO3. As a result, the photoelectrochemical (PEC) and photovoltaic (PV) performance of BFO could be enhanced. We developed the BiFeO3 nanostructures via a facile approach and then we have deposited Au nanoparticles on the surfaces of the BiFeO3 nanoparticles. Electron microscopic images revealed the aggregation of 20–40 nm sized BiFeO3 nanoparticles and the spherical shaped Au nanoparticles of ~ 30 nm. In addition to a noticeable enhancement in the optical spectrum, the plasmonic effect could be seen in the absorbance spectra after the decoration of Au nanoparticles. In order to assess the enhanced photovoltaic and photoelectrochemical performance of the Au-decorated BFO nanostructures, a comparative examination of pristine BFO was performed. Studies on the time-dependent photocurrent density also confirmed the stability of treated photoelectrode materials using Au nanoparticles. This really raised the charge transfer efficiency by delivering better conductivity, which was investigated using Nyquist plot. The incident photon-to-current conversion efficiency [IPCE(%)] also confirmed the enhancement of photovoltaic by Au nanoparticles. The DSSC efficiency of produced Au-decorated BiFeO3 nanostructures is ~ 20% higher than the pristine BiFeO3-based cells. [ABSTRACT FROM AUTHOR]

Postural stability may be affected during slope walking, as there are different body kinetics and kinematic responses compared with level walking. Understanding body adaptations toward different inclinations is essential to prevent the risk of injury from falls or slips. This study was conducted to determine the correlations between stability parameters and loading response in terms of joint reaction force at the lower-extremity joints during inclined and declined walking. Twenty male subjects walked in the level, incline, and decline directions on a custom-built platform at three different slope angles (i.e., 5°, 7.5°, and 10°). To determine the ground reaction force (GRF), joint reaction force (JRF), center of pressure (COP), and center of mass (COM), a motion capture system was used to read the data of the ten reflective markers and transfer them to visual three-dimensional (3D) software. Pearson's correlation test was performed with statistical significance set at p < 0.05 to evaluate the correlation of the required coefficient of friction (RCOF), postural stability index (PSI), and COP-COM distance with the JRF. This study has identified that the JRF changes in opposition to the changes in the RCOF during the initial strike during incline and decline walking, as JRF increases, the RCOF decreases with different strengths of correlation. There is also a strong positive correlation between the PSI and JRF in the proximal–distal direction, where the JRFs change in accordance with the change in the PSI, and the JRF increases with the increment of PSI. In addition, the JRF of the lower extremity also changed in a manner similar to the COP-COM distance in the medial–lateral direction. Overall, each stability parameter was correlated with the JRF of the lower-extremity joints in different directions and strengths. This study demonstrated that slope walking is particularly affected by surface inclination in terms of stability and loading. Therefore, this research can serve as a basis for future studies on slopes, as there is no specific basis for a maximum degree of inclination that is safe and suitable for all applications. [ABSTRACT FROM AUTHOR]