The aim of this study is to evaluate the effect of different concentrations of citral on glutathione (GSH), nitric oxide (NO), lipid peroxide (LPO) and vitamin C. Also, the protective effect of N. sativa was studied. Fertilized eggs of the chick Gallus domesticus were divided into control or experimental groups which received three different concentrations of citral (50, 100 and 200 μM), N. sativa extract (5 μl) or a combination of N. sativa extract with citral. Citral and N. sativa groups decreased GSH & vitamin C and NO, while increased LPO. Co-treatment with citral and N. sativa increased GSH & vitamin C and decreased LPO levels. Citral induced oxidative stress by inhibiting RA synthesis. The limited mitigative properties of N. sativa are attributed to either its antineoplastic properties, the high levels of oxidative stress provoked by citral and above its antioxidative capacity or the low administered dose.

Purpose – This paper aims to investigate the entropy generation due to magnetohydrodynamic natural convection flow and heat transfer in a porous enclosure filled with Cu-water nanofluid in the presence of viscous dissipation effect. The left and right walls of the cavity are thermally insulated. There are heated and cold parts, and these are placed on the bottom and top wall, respectively, whereas the remaining parts are thermally insulated. Design/methodology/approach – The finite volume method is used to solve the dimensionless partial differential equations governing the problem. A comparison with previously published woks is presented and is found to be in an excellent agreement. Findings – The minimization of entropy generation and local heat transfer according to different values of the governing parameters are presented in details. It is found that the presence of magnetic field has negative effects on the local entropy generation because of heat transfer and the local total entropy generation. Also, the increase in the heated part length leads to a decrease in the local Nusselt number. Originality/value – This problem is original, as it has not been considered previously.

Magnetohydrodynamic natural convection flow and heat transfer in a square porous cavity differentially heated and cooled by heat source and sink, respectively, and filled with the Cu–Al2O3–water hybrid nanofluid isstudied numerically. The active parts of theleft and the right side walls of the cavity are maintained at cooled temperature, and the active parts of the top and bottom walls are maintained at hot temperature. The enclosure’s inactive parts of its side walls are kept insulated. The governing equations in the two-dimensional space are discretized using finite difference methodology. A proper upwinding scheme is employed to obtain stabilized solutions. Using the developed code, a parametric study is undertaken, and the effects of the Rayleigh number, the locations of the active parts of the side walls, and the volume fraction of the nanoparticles on the fluid flow and heat transfer inside the cavity are investigated. It is observed from the results that the average Nusselt number decreases substantially for hybrid suspension when the location of the heat source D changes. It is noted that the velocity decreases in magnitude when Hartmann number Ha increases. The local Nusselt number gets enhanced for the hybrid suspension as the nanoparticle volume fraction ϕ increases. It is also shown that, as compared to Cu and Al2O3, the hybrid suspension has lower magnitude of average Nusselt number.

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Chalcogenide glasses have received lots of attention because of their superior optical properties. To optimize these properties and expand areas of applications, more studies are required to establish the extent to which the parameters can be tuned over a wide range of annealing temperatures and heating rates. To do this, bulk and thin ∼150 nm As30Te67Ga3 films were prepared by melt-quenching and thermal evaporation techniques,respectively. The phase transition was investigated using differential scanning calorimeter (DSC) while the crystal structures were studied by X-ray diffraction (XRD). Characteristic temperatures such as the glass transition, crystallization and melting temperature of the bulk glass were found to depend on the heating rate. The activation energy of glass transition was 167.29 kJ/mol while the energy of crystallization was 103.98 kJ/mol. XRD results indicated that the annealed films showed more crystallinity, larger average crystallite size, lower dislocation density and lower strain as annealing temperature increased. According to the Avrami exponent, a combination of two and three-dimensional crystal growth with heterogeneous nucleation are possible mechanisms for the crystallization process. Moreover, optical constants such as the optical band gap, refractive index, extinction coefficient, high-frequency dielectric constants, real and imaginary parts of dielectric constants were found to strongly depend on the annealing temperature. The optical energy gap decreased from 1.1 to 0.89 eV as the annealing temperature increased from 373 to 433K. These results indicate that thermal annealing is a major factor that can be used to tune the crystal structure, and hence the optical properties of As30Te67Ga3 system.

Chalcogenide glasses have received lots of attention because of their superior optical properties. To optimize these properties and expand areas of applications, more studies are required to establish the extent to which the parameters can be tuned over a wide range of annealing temperatures and heating rates. To do this, bulk and thin ∼150 nm As30Te67Ga3 films were prepared by melt-quenching and thermal evaporation techniques,respectively. The phase transition was investigated using differential scanning calorimeter (DSC) while the crystal structures were studied by X-ray diffraction (XRD). Characteristic temperatures such as the glass transition, crystallization and melting temperature of the bulk glass were found to depend on the heating rate. The activation energy of glass transition was 167.29 kJ/mol while the energy of crystallization was 103.98 kJ/mol. XRD results indicated that the annealed films showed more crystallinity, larger average crystallite size, lower dislocation density and lower strain as annealing temperature increased. According to the Avrami exponent, a combination of two and three-dimensional crystal growth with heterogeneous nucleation are possible mechanisms for the crystallization process. Moreover, optical constants such as the optical band gap, refractive index, extinction coefficient, high-frequency dielectric constants, real and imaginary parts of dielectric constants were found to strongly depend on the annealing temperature. The optical energy gap decreased from 1.1 to 0.89 eV as the annealing temperature increased from 373 to 433K. These results indicate that thermal annealing is a major factor that can be used to tune the crystal structure, and hence the optical properties of As30Te67Ga3 system.

Although there is a plenty of work in many publications concerning three-dimensional (3D) pore formation by an anodization process, though no definitive conclusion has been given to the mechanism of its formation. Accordingly, the process of 3D architecture is still a subject of considerable debate. The aim of the present study is to extend the previous findings, bringing out the relationship between different components such as the thermodynamic role of the precipitations mechanism in dilute aluminum (Al) alloy at the alloy/oxide interface, film thickness, anodizing potential and the resulting porous anodic alumina (PAA) film morphology. Dislocation movement following Orowan mechanism and its role in enriching layer formation is connected for the first time in explaining the formation of the enriched layer. Consequently, the precise disruption of the 3D morphologies within the anodic films is developed. The distributions of copper (Cu) spices in the alloy as well as within the enriched layer on the alloy/oxide surface are carefully investigated and explained using different experimental techniques. In addition, the oxygen generation is explored. The present study is designed to reveal the influences of impurities on the PAA architecture. It has the advantage of being a direct explanation for the mechanism of the defect in the PAA and its incorporation into the anodic film throughout the anodic film. Moreover, a reliable explanation for current density oscillation is explored. That help to gain further understanding of this phenomenon o control PAA structure in thermodynamically similar alloys. Based on the present study, free Cu atoms in solid solution are swept driven by vacancies according to Orowan interface during anodization forming an enriched ~2 nm layer of Cu just beneath the anodic film. The Cu is not significantly incorporated into the anodic film before the formation of θ′ precipitates in a thick film; whereas of thickness500 nm, the Cu atom migrates outward forming patterned precipitates rest at the surface for the thin film. The concentration of θ′ precipitates is calculated and found ~9×1015m−3. Accordingly, the Cu incorporation into the anodic film and 3D structure mechanism are correctly explored.