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This study investigates the characteristics of an unsteady, incompressible, and electrically conductive flow. The flow consists of H2O based nanofluid that contains suspended sphere-shaped Cu nanoparticles. The flow occurs across an oscillating and porous vertical plate. Simultaneous non-dimensional governing partial differential equations are solved by pdepe solver in MATLAB 22a, accounting for thermophysical properties and relevant parameters. We analyzed the behavior of the Cu -H2O nanofluid in relation to various fundamental parameters, including thermal buoyancy force, kinetic energy, thermal conductivity, volume fraction of nanoparticles, and time. Additionally, we determined the rate of local heat transfer and skin friction of the Cu-water nanofluid, presenting the results in tabular form. Our findings were compared with previously reported results to validate the accuracy and reliability of the pdepe solver. The pdepe solver in MATLAB is a straightforward and convenient tool for simulating and visualizing models, It is an alternative method for solving IBVP of parabolic & hyperbolic.

For a future commercial fusion reactor, the joining of tungsten and steel will be of vital importance, covering the main part of the plasma facing area. However, the large difference, of more than a factor of 2, in the coefficient of thermal expansion (CTE) of W and steel results in high thermal stresses at their interface. The cyclic nature of the operation can cause fatigue effects and could result in a premature failure of the joint.One possible solution is the insertion of a functionally graded material (FGM), with varying the CTE, as an interlayer between tungsten and steel, which could reduce these stresses. In this study, two processes, atmospheric plasma spraying (APS) and spark plasma sintering (SPS), are utilized to manufacture such FGMs. The gradation was accomplished by using two or three layers with a thickness of 0.5 mm each.Another principle is the insertion of a ductile metal interlayer, which reduces the stress by plastic deformation. Vanadium and titanium foils of varying thickness were chosen, as both have a CTE in between W and steel and V forms a solid solution with W and Fe. These and a direct W-steel joint as baseline reference were made by current-assisted diffusion bonding. All samples consist of 3 mm thick W and steel tiles allowing a direct comparison of the different technologies.An efficient high heat flux benchmark test procedure was developed and performed to investigate and compare the potential of the different joining technologies. For this, the complete stacks were brazed on actively cooled copper cooling modules and tested with high stationary heat loads of up to 5 MW/m2 with 200 cycles at each level in the JUDITH 2 facility. Detailed thermal analysis including comparison with prediction based on FEM simulation are presented to understand the cause of the failure and track the degradation. This study allows to help focusing the further development of W-steel joining technologies.

The approximate controllability results of Atangana-Baleanu fractional stochastic integrodifferential systems with infinite delay are the topic of this paper. The essential discoveries are developed by employing techniques and theories from stochastic analysis, multivalued map theory, fractional calculus, and fixed point procedure. Before establishing the fractional stochastic control system’s approximate controllability, we illustrate the existence of mild solutions. Ultimately, an example is offered to clarify our main points.

Herein, the proposed work reports a simple chemical approach; solution combustion method to synthesize ZnO nanoparticles and Nd-doped ZnO (Nd2O3-ZnO) nanocomposites (0.001 g–5 g) using the combustion technique. The combustion approach is considered one of the environmentally friendly, cost-effective, high yields, and most straightforward procedures for rapidly preparing nanomaterials on a large scale. The prepared nano samples were characterized through standard analytical methods, including scanning electron microscopy (SEM), X-ray Diffraction (XRD), UV–Vis–NIR, and Fourier transform infrared spectroscopy. The XRD results and SEM image showed that the manufactured Nd2O3–ZnO nanostructured samples were crystalline with uniform distribution of Nd dopants on the host ZnO samples, clear with higher Nd concentration ratios. Moreover, as the Nd was raised in the Nd2O3–ZnO nanostructures, the direct energy bandgap values of the Nd: ZnO nanocomposites were detected to decline from 3.35 eV for pure ZnO to reach 3.26 eV, and the indirect bandgap diminished from 3.28 eV to 3.20 eV. All prepared Nd2O3–ZnO samples were applied for photocatalytic degradation of Rhodamine B, Methylene Blue, and both. The photocatalytic efficiency increased with the Nd doping ratio. The best photocatalyst is 0.5 g Nd2O3 doped-ZnO, which degrades Methylene Blue, Rhodamine B, and combination solutions containing both dyes with 100% against ZnO alone with 80% within 60 min under the visible light. Compared to the pure ZnO nanoparticles, the synthesized Nd2O3–ZnO nanostructured samples disclosed improvements in the structural morphology, optical, energy bandgaps, dielectric refraction, and electrical and photocatalytic properties.

Yttrium oxide/CuO nanocomposite with different concentrations of Y2O3 were synthesized by a combustion technique. The structural, morphology, and photocatalytic properties were investigated using X-ray diffraction, SEM and photodegradation studies respectively. Scanning electron microscopy images reveal the porous nanocomposite morphology with significant aggregation. The photocatalyst degraded both carmine and methylene blue (MB). An attempt was made to discover the optimal circumstances of degradation, including time of contact, H2O2 concentration, and light exposure. Under UV irradiation, 2.5% Y2O3 -CuO nanocomposite demonstrated optimum photocatalytic efficiency of up to 55.68% in 70 min, with a rate constant of around 0.0079 min−1 for MB. However, the photocatalytic efficiency of the 1% Y2O3/CuO nanocomposite increased to 87.95% in 70 min, with a rate constant of about 0.01826 min−1 for carmine under UV irradiation. The findings demonstrated that UV light increased the reaction rate more than visible light. Furthermore, the research showed that carmine is degraded faster than MB. Cyclic experiments showed the Y2O3/CuO nanocomposite stability over repeated use. The photocatalytic reaction species trapping studies were performed with 1% Y2O3/CuO nanocomposite and UV light.

Abstract Graphene‐based nanomaterials are gaining importance in biomedicine because of their large surface areas, solubility, and biocompatibility. Green synthesis is the most economical method for application, as it is rapid and sustainable. Biofunctionalized reduced graphene oxide (TrGO) nanosheets were synthesized using methanol extract of Turbinaria ornata, and bioreduction of graphene oxide was primarily confirmed and characterized using UV‐visible, Fourier transform infrared (FTIR), and X‐ray diffraction spectroscopy and further characterized by zeta potential and transmission electron microscopy. The FTIR spectra of TrGO showed a decrease in the band intensities of oxygen groups, thus confirming effective deoxygenation. The zeta potential value of −34.6 mV revealed that synthesized TrGO was highly stable. The cytotoxic effect of TrGO against MCF‐10A and MCF‐7 cells was ascertained using MTT assay, showed a greater cytotoxic effect on MCF‐7 cells. The IC50 of TrGO treatment against MCF‐7 was calculated to be 31.25 µg, which is onefold lower than the cytotoxic effect of methanolic extract of T. ornata (60.0 ± 1.14 µg/ml). In addition, there was a statistically significant difference in cell viability between MCF‐10A and MCF‐7 cells in the treatment of TrGO. Hence, this study results in an efficient green reductant for producing rGO nanosheets that possess cytotoxicity against breast cancer cells.

Abstract Modern day hospital treatments aim at developing electrochemical biosensors for early diagnosis of diseases using unconventional human bio-fluids like sweat and saliva by monitoring the electron transfer reactions of target analytes. Such kinds of health care diagnostics primarily avoid the usage of human blood and urine samples. In this context, here we have investigated the electron transfer reaction of a well-known and commonly used redox probe namely, potassium ferro/ferri cyanide by employing artificially simulated bio-mimics of human sweat and saliva as unconventional electrolytes. Typically, electron transfer characteristics of the redox couple, [Fe(CN)6]3−/4− are investigated using electrochemical techniques like cyclic voltammetry and electrochemical impedance spectroscopy. Many different kinetic parameters are determined and compared with the conventional system. In addition, such electron transfer reactions have also been studied using a lyotropic liquid crystalline phase comprising of Triton X-100 and water in which the aqueous phase is replaced with either human sweat or saliva bio-mimics. From these studies, we find out the electron transfer reaction of [Fe(CN)6]3−/4− redox couple is completely diffusion controlled on both Au and Pt disc shaped electrodes in presence of sweat and saliva bio-mimic solutions. Moreover, the reaction is partially blocked by the presence of lyotropic liquid crystalline phase consisting of sweat and saliva bio-mimics indicating the predominant charge transfer controlled process for the redox probe. However, the rate constant values associated with the electron transfer reaction are drastically reduced in presence of liquid crystalline phase. These studies are essentially carried out to assess the effect of sweat and saliva on the electrochemistry of Fe2+/3+ redox couple.

The synthesis of pure and different concentrations of Cr-doped (1, 2.5, 5, 7, 10 wt%) lead iodide (PbI2) nanosheets was successfully achieved using a low-cost and simple microwave method. The prepared Cr-doped PbI2 nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), FT-Raman, diffuse reflectance, dielectric, and gamma absorption analysis. The structural investigation confirmed the hexagonal phase of the proposed nanostructures without the impurity phase. Morphological studies proved that the undoped PbI2 nanosheet has a size of less than 100 nm, and the size of the prepared Cr-doped PbI2 samples was around 50-60 nm. FT-Raman and optical analysis investigated the doping effects on the pure PbI2 matrix through the slight shifting of characteristics peaks and the energy bandgaps’ variations. The optical bandgap values of pure PbI2 and Cr-doped PbI2 samples were estimated to be ranged from 2.0 eV to 2.2 eV. The obtained values of the dielectric constant were increased from 20 to 27 due to introducing the Cr- ions into the host PbI2 matrix. Together with Cr- dopants, the linear coefficient of Gamma absorption illustrates improvements. To conclude, due to the enhancement in structural morphology, optical, and radiation properties of the synthesized Cr-doped PbI2 nanostructures, those proposed nanosheets potentially are remarkable candidates for various applications including optoelectronics and radiation detectors.

Past studies have shown that phosphate recovery in the form of struvite is relatively a simple process, which can be achieved by adding a magnesium source in stored urine. However, struvite recovery process at a decentralised level becomes uneconomical due to high input cost of magnesium salts and operational cost. While use of cheaper alternative magnesium sources such as bittern, low-grade MgO and wood ash could lead to partial cost reduction, it is also important to reduce the overall operational costs to make struvite recovery process economically viable and sustainable. In this study, a continuous flow reactor was developed for low-cost struvite recovery from stored urine at decentralised community scale operations. Our study revealed that over 81.2% of phosphate present in urine can be recovered in the form of struvite. Comparison of results from stirred and unstirred experiments shows that higher recovery efficiency is obtained due to minimal loss of fines. Operation and financial assessment of the process shows that struvite recovery can be profitable due to continuous operation of the reactor requiring minimal process control and manpower requirement.

Large size growth of Zinc(tris) thiourea sulphate (ZTS) crystals has been successfully done through slow solvent evaporation technique in presence of l-Ascorbic acid (LAA). The possibility of any extra phase due to presence of LAA was ruled out through structural analysis. The deviation in lattice parameters and shift in peaks position indicates the interaction of LAA with ZTS. Crystalline perfection of grown crystals was judged by High-resolution X-ray diffraction (HRXRD) study and found that the crystalline perfection of ZTS in presence of 10 wt% LAA is enhanced compared to others. The low optical absorbance and high band gap confirms its application in optoelectronic devices. A burly blue emission band at 460 nm was observed in Photoluminescence spectra of ZTS crystals grown in presence of LAA when excited at 310 and 358 nm both. However, when these specimens were excited at 385 nm this blue emission band is observed at 470 nm. The remarkable enhancement of blue band emission intensity was noted which may be attributed due to presence of defects (color centers). Further the dielectric measurement was done and shows that the dielectric constant has been improved due to presence of LAA. The enhanced optical band gap, photoluminescence intensity and dielectric constant suggests that the LAAZTS single crystals are suitable for electro-optic device applications. Keywords: Crystal growth, X-ray diffraction, HRXRD, Optical properties, Dielectric response

The present work addresses the important need of new materials to improve energy storage materials. The synthesis of MnCo2O4 nanospheres by employing solvothermal method at different incubation times was carried out. The effects of reaction time on structural, morphological, and electrochemical studies were briefly investigated. The X-ray diffraction result unveils the formation of cubic-structured MnCo2O4 nanospheres with Fd3m (2 2 7) space group. The appearance of two Raman peaks at 480 and 662 cm−1 was greatly attributed to the stretching vibration mode of M–O (M = Mn, Co), and substantiates the formation of MnCo2O4. The presence of functional group and characteristics group was analyzed by Fourier-transform infrared spectroscopy. The scanning electron microscope image clearly indicated different sizes of nanoparticles due to the effect of solvothermal reaction period. The energy storage behavior of MnCo2O4 nanospheres was studied by employing the cyclic voltammetric and charge–discharge cycles. The results confirmed the pseudocapacitive nature of MnCo2O4 nanoparticles (RF3) with porous, spherical nanostructure with larger radius than others and contribute to better specific capacitance of 252 F g−1 at current density of 1 A g−1 which could be considered as a potential candidate for pseudocapacitive electrode for energy storage devices. Keywords: Cubic, MnCo2O4, Nanospheres, PVP, Fd3m (2 2 7) space group, Energy storage

Designing photocathodes with nanostructures has been considered a promising way to improve the photoelectrochemical (PEC) water splitting activity. Cu2Te is one of the promising semiconducting materials for photoelectrochemical water splitting, the performance of Cu2Te photocathodes remains poor. In this work, we report the preparation of Cu2Te nanorods (NRs) and vertical nanosheets (NSs) assembled film on Cu foil through a vapor phase epitaxy (VPE) technique. The obtained nano architectures as photocathodes toward photoelectrochemical (PEC) performance was tested afterwards for the first time. Optimized Cu2Te NRs and NSs photocathodes showed significant photocurrent density up to 0.53 mA cm−2 and excellent stability under illumination. Electrochemical impedance spectroscopy and Mott–Schottky analysis were used to analyze in more detail the performance of Cu2Te NRs and NSs photocathodes. From these analyses, we propose that Cu2Te NRs and NSs photocathodes are potential candidate materials for use in solar water splitting.