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Combined experimental and theoretical analysis reveals the superior properties of Co1−xNixFe2O4 nanoparticles – a putative candidate for energy-harvesting applications.

The present study focuses on optimization of operating parameters in wire electric discharge machining of AA2024 aluminium alloy reinforced with lithium and silicon nitride particles. Aluminium composite was produced through the two-step stir casting route with the combination of 2% lithium and 10% silicon nitride reinforcements. Experiments were performed using the Taguchi design of experiments to optimize the selected input parameters such as pulse on time, pulse off time, current and wire feed for the response parameter, material removal rate, and surface roughness. An ANOVA-based regression equation with genetic algorithm was used to optimize the input variables. The gray relational grade was also performed to optimize multiple performance characteristics. Taguchi-based optimization analysis results in wire feed as the domination factor for material removal rate and surface roughness. Increased wire feed increases the material removal rate with good surface finish as confirmed from gray relational grade analysis. Regression equation generated results with minimum error (

Pr2O3 doped bismuth-phosphate glasses have been produced via an ordinary melt quenching tool. Glasses have a chemical content (5–x) Al2O3–15Na2O–20Bi2O3–60 P2O5 –xPr2O3 with x values between 0 and 2 mol%. The structural and mechanical features of the prepared phosphate-based glasses were investigated. The XRD spectra confined the amorphous type of these glasses. Furthermore, the influence of Pr2O3 on the mechanical features has been explored and related to the structure. The relationship between structural variations and the contents of Pr2O3 has been investigated in terms of FTIR and by the determination of the density and the ultrasonic velocity. The density and the ultrasonic velocities were utilized to calculate the elastic moduli of the glasses. The acquired results indicate that the ultrasonic velocity and the elastic moduli increase as a function of Pr2O3 in the whole explored studied glasses. The analysis of FTIR spectra refers that Pr2O3 is interstitial settled in the phosphate network with [PrO7] associated with covalent Pr–O–P bonds, whereas Bi2O3 and Al2O3 settle on the network with [BiO6], and [AlO6] units. These experimental features coincide with a compact structure and act in a manner that Pr2O3 incorporates the glassy network with plenty of bridging oxygen atoms. These arguments encourage the use of these glasses in radiation shielding materials.

This article is allocated to study optical characteristics of a-(Cu2ZnGe)50−xSe50+x, CZGSe, ( 0 ≤ x ≤ 20 at wt % ) films. The amorphous nature of films was affirmed via X-ray diffractograms. energy-dispersive X-ray spectroscopy confirmed the matching between selected compositional element percentages and those measured for all films. Many optical properties and parameters of CZGSe films were studied using UV–vis-INR spectroscopic transmission and reflection measurements. The envelope methods have been successfully applied on the measured transmission spectra according to Swanepoel technique, along with reflection spectra in accordance with Minkov method. Obtained results based on Swanepoel analysis are in excellent agreement with those inferred from Minkov method. A clear blueshift of the absorption edge was observed from 854 nm to 720 nm, in accordance with the increasing optical bandgap energy values from 1.456 eV to become 1.722 eV, as Se-content increases from 50 to 70 at wt%. The electronic transitions of (Cu2ZnGe)50−xSe50+x films arose from allowed indirect transitions. This observed energy gap increases was interpreted according to the Mott and Davies model. The absorption coefficient values have been estimated and discussed, it is found to be larger than 10−4 cm−1. All discussed parameters strongly depend on the Se-concentration. The bonding strength between the elements of samples strongly affects the optical properties.

The Co0.5Ni0.5CexSmyFe2-x-yO4 (CNCSF) XRD pattern revealed the purity of the samples without any secondary phase. The crystallite size CNCSF are in nano range. Further, the calculated lattice parameter of CNCSF are found to increasing with the RE content. From SEM micrographs surface morphology and the microstructure of the CNCSF was studied. The porous nature of the samples is revealed by SEM, which will aid in increasing their sensing response. Energy dispersive X-ray spectroscopy (EDS) patterns have confirmed the stoichiometric presence of Co2+ Ni2+, Ce3+, Sm3+ and Fe3+, those are used to prepare the CNCSF. The dielectric behaviour is similar to that of conventional spinel ferrite structures, in that the dielectric constant is highest at low frequencies and decreases at higher frequencies due to electron hopping, resulting in dielectric dispersion. Only one semicircle is seen in each Cole-Cole plot, which has uncovered that the contribution to conductivity is predominantly from the grain boundaries. At room temperature, the gas sensing responses of CNCSF thin films were investigated. For liquified petroleum gas (LPG), the gas sensing characteristics of the prepared thin films were investigated. At room temperature, the x = 0.03 thin films showed excellent sensitivity to liquified petroleum gas. The sensing response and recovery time of all of the thin films that had been prepared were reported. The sensing response of x = 0.03 thin films was highly stable over a period of 60 days on exposure to LPG (1000 PPMv), according to the stability analysis. The sample thin film with x = 0.03 can be utilized in gas sensor technology, particularly for the detection of LPG at room temperature, due to its increased sensitivity, quick response and recovery times, and stability.

Se–Te materials have shown promise in optoelectronic applications. A combination of enhanced optical and mechanical properties represents a good candidate for optical limiting devices. Here, we report the influence of Ag additive on the optical and mechanical properties of ( S e 70 T e 30 ) 100 − x A g x ( 0.0 ≤ x ≤ 8.0 a t . % ) chalcogenide thin films. The reflectance spectra of amorphous thin films have been analyzed in the spectral range 0.3 μm–2.5 μm. The optical parameters are obtained using reflectance spectra of the thin films. The refractive index increases with the addition of Ag, while the optical band gap decreases from 1.40 eV to 1.11 eV. The reduction in the optical band gap is correlated with the raise in the concentration of defect states and the disorder. The nonlinear refractive index and nonlinear susceptibility have been evaluated and found to show an augmented response with Ag content. The value of ( χ ( 3 ) ) increases from 3.44 × 10−11 esu to 7.66 × 10−11 esu and n2 from 3.98 × 10−10esu to 8.08 × 10−10esu. The mechanical properties have also been analyzed theoretically and ultrasonically with Ag incorporation to SeTe thin films.

Highly homogenous crystal violet (CV) thin films are grown by spin coating technique. X-ray diffraction (XRD) measurements have been carried out to identify the dominant orientation of the films. The XRD pattern of as-deposited film showed an amorphous structure which turns into nanocrystalline by thermal annealing at 150 °C for 1 h. The spectroscopic characterization of as-deposited and annealed CV films was estimated via spectrophotometric measurements of transmission and reflection in the spectral range 190–2000 nm. Optical constants of CV films were determined. Wemple-DiDomenico model was applied to the normal dispersion region of refractive index spectrum and from which, many dispersion parameters were calculated. The type of most probable transitions and values of optical energy gaps for CV films were estimated by Tauc plot. The dissipation energy and volume & surface loss functions were estimated. The influence of annealing temperature on the spectroscopic properties, dispersion parameters and energy loss functions were investigated which revealed an improvement in the optical properties and decreased values of energy loss functions for the annealed CV films. The obtained results of optical features for CV films reveals that CV films are an excellent potential absorbing material in solar energy conversion and storage devices.