In this paper, a thorough radio- and chem-ecological evaluation of ElSibai-Abu ElTiyur granites located within Egypt’s crystalline basement rocks was conducted for risk and dose assessments. Twenty granitic samples from the study area’s various lithological units were analyzed using high-resolution γ-ray spectrometry to determine the natural radioisotopes (U-238, Th-232, and K-40) concentrations. The average concentrations of U-238, Th-232, and K-40 were 38.72, 38.23, and 860.71 Bq/kg, respectively, exceeding the GAV (global average value) documented by UNSCEAR (Scientific Committee on the Effects of Atomic Radiation, Vienna, Austria). The radiological parameters and indices judging the usage of ElSibai-Abu ElTiyur granites in homes were computed. The obtained results showed that ElSibai-Abu ElTiyur granites are safe to be used by inhabitants as superficial building materials, as per the globally accepted values and the recommended safety limits approved by UNSEAR, WHO (World Health Organization, Geneva, Switzerland), ICRP (International Commission on Radiological Protection, Ottawa, ON, Canada), and EC (European Commission, Luxembourg). Further, the samples were subjected to ICP-MS (inductively coupled plasma mass spectrometry) analysis for quantifying radionuclide variations with chemical composition. Geochemically based on the ICP-MS results, the studied granites proved to be highly evolved A-type granites. They span the metaluminous to peralkaline fields. The REE patterns are characterized by the enrichment of the light rare earths (LREE) over the heavy ones (HREE) where (La/Yb)_n = 5.2, (Gd/Yb …

Integrated field, litho- and bio-stratigraphic analyses were carried out on three Maastrichtian–Paleocene successions exposed at the Gabal Wasif, Wadi Syatin and Gabal Hamadat sections, in the Safaga-Quseir region, Red Sea Coast, Egypt. Two formations are recognized; the Dakhla Fm. and the overlying Tarawan Fm. High resolution planktonic foraminiferal investigations resulted in the identification of eleven planktonic foraminiferal zones that represent four hiatuses caused by three syn-sedimentary tectonic events (I, II and III). These events are related to the onset of the Syrian Arc Orogeny. Tectonic Events I and II coincide with the Cretaceous/Paleogene (K/Pg) and Danian/Selandian (D/S) boundaries, respectively, while Tectonic Event III occurred at the end of the Paleocene (latest Paleocene). Five paleo-relief profiles demonstrate the relative magnitudes of these tectonic events and their impact on the evolution of the sedimentary basin. Tectonic Event I had a regional effect and is seen in two sedimentary basins that are separated by a submarine paleohigh identified in the W. Syatin section. Tectonic Event II reached a maximum in magnitude toward the north in the Safaga area, forming a paleohigh in the G. Wasif and W. Syatin sections, while the G. Hamadat section represents the depocenter. Tectonic Event III had a limited impact toward the north in the Safaga area, where it formed a paleohigh at G. Wasif.

This article studies the boundary layer flow analysis and heat and mass transfer of magnetohydrodynamic (MHD) Carreau fluid around a stretchable circular cylinder, comprehensively studying the suspended dust particles' impact. Here, the viscous fluid is theorized to be incompressible and loaded with spherical dust particles of the same size. Additionally, heat and sink sources are examined in the thermal boundary layer in the existence of both chemical reaction and activation energy influences. A compatible similarity set of transformations are utilized to mutate the system of partial differential equation formed in momentum and temperature equations of the fluid and dust phases as well the concentration equation into a set of ordinary differential equations. Therefore, the mathematical analysis of the problem facilitates and the numerical estimates of the problem are obtained using MATLAB bvp4c function. Computations are iterated for various values of emerging physical parameters from dimensionless boundary layer conservation equations in terms of temperature and non-Newtonian Carreau velocity of fluid and dust phases and concentration distribution. Moreover, the terminology of skin friction and Nusselt and Sherwood numbers have been obtained and studied numerically. Some interesting findings in this study are the heat transfer rate dwindles due to the increase of mass concentration of the dust particle. Also, there is a strengthening of the flow with variance in values of the curvature parameter while a weakening has been observed in the thickness of the thermal boundary layer and this hence improves the heat transfer rate. Therefore, the fluid flow around a stretched cylinder would be better, due to its multiple applications in various progressing industrial technologies such as the cement processing industry, plastic foam processing, watering system channels, and so forth. Also, activation energy plays a significant role in various areas such as the oil storage industry, geothermal, and hydrodynamics.  The dusty fluid flow is very important in the field of fluid dynamics and can be found in many natural phenomena such as blood flow, the flow of mud in rivers, and atmospheric flow during mist. Moreover, MHD applications are numerous including power generation, plasma, and liquid metals, and so forth. A perfect agreement between our results and other studies available in the literature is obtained through carrying out a comparison with treating the problem in special circumstances.

The focus of this paper is to examine non-similar solutions of dusty non-Newtonian Casson nanofluid flow around the surface of an isothermal sphere in the presence of magnetic field impact. It is presupposed that the impacts of thermophoresis and Brownian motion are considered into regard in the nanofluid model. In addition to the thermophoresis impact, the normal flux of nanoparticles is equal to zero at the boundary. With respect to the fluid temperature, the surface of the isothermal sphere is preserved at a constant temperature. The dust particles preassumed to having the same size and conform in the spherical shape to the nanoparticles. Suitable non-similarity transformations are utilized to mutate the governing partial differential equations for fluid and dust phases into a system of non-linear, coupled, and non-similar partial differential equations. The generated non-similar equations are solved using numerical technique renown MATLAB function bvp4c and the results are represented in terms of velocity and temperature of fluid and dust phases, and concentration distribution as well as the skin-friction coefficient and heat transfer rate. Obtained results indicate that increasing the mass concentration of the dust particles in the nanofluid leads to depression the motion and an enhancement in the rate of heat transfer. For the nanofluid phase and dust particle phase, the temperature magnitude improves with increasing of the stream wise coordinate additionally the distribution of velocity accelerates away from the sphere surface i.e. with high values of the radial coordinate η.

In this study, a novel, simple and sensitive square wave voltammetric method for the determination of elbasvir (ELB) using Mn₅O₈-modified pencil graphite electrode (PGE) was developed. Mn₅O₈ nanoparticles (NPs) were synthesized by calcination of manganese malonate at 350 °C for 24 h. The structure of Mn₅O₈ was characterized by X-ray powder diffraction (XRD), Fourier transform infrared (FT-IR) and Raman spectroscopy. Nitrogen adsorption-desorption measurements showed that Mn₅O₈ NPs possess a mesoporous structure with a specific surface area of ~32 m²/g. After characterization, Mn₅O₈ NPs were applied to the electrode surface in a “drop-casting” fashion. Scanning electron microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV) were employed to investigate the differences between the Mn₅O₈-decorated PGE and bare PGE. Under the optimized experimental conditions, the modified PGE gives a linear response over the concentration range of 0.20 to 3.00 μmol L⁻¹ ELB with low limits of detection and quantitation, which were found to be 0.04 and 0.13 μmol L⁻¹, respectively. For the first time, the photo-stability and the photo-induced dimeric-monomeric conversion behavior of ELB were studied using FT-IR, spectrophotometric, spectrofluorimetric and mass spectroscopic techniques. The fabricated electrode exhibits good precision, selectivity, and sensitivity that could be applied successfully for sensitive determination of ELB in its bulk form, in quality control laboratories and biological fluids.

A novel, simple and sensitive electrochemical method for the determination of ledipasvir (LED), the newly FDA approved Hepatitis C antiviral drug was developed and validated using ε-MnO₂-modified graphite electrode. Two different MnO₂ polymorphs (γ- and ε-MnO₂nanoparticles) were synthesized and characterized using X-ray powder diffraction (XRD), Fourier transform infrared (FTIR), energy dispersive X-ray (EDX) and thermogravimetric analysis (TGA). Surface area measurements show that ε-MnO₂ NPs have large surface area of 345 m²/g, which is extremely high if compared to that of γ-MnO₂ NPs (38 m²/g). In addition, a comprehensive study of the difference in the electrochemical behavior of LED while using pencil graphite electrode (PGE) modified with either γ- or ε-MnO₂ NPs is carried out. It was found that surface area and percentage of surface hydroxyls of MnO₂ NPs are the key factors governing the sensitivity of the fabricated electrode toward the oxidation of the positively charged LED. Scanning electron microscopy (SEM) was employed to investigate the morphological shape of MnO₂ NPs and the surface of the bare and modified electrodes. Moreover, cyclic voltammetry and electrochemical impedance spectroscopy (EIS) were used for the surface analysis of the modified electrodes. Based on the obtained results, ε-MnO₂/PGE was applied as a selective and sensitive electrode for determination of LED. Under the optimized experimental conditions, ε-MnO₂/PGE provides a linear response over the concentration range of 0.025–3.60 μmol L⁻¹ LED with a low limit of detection, which was found to be 5.10 nmol L⁻¹(4.50 ng mL⁻¹) for the 1^st peak and 9.20 nmol L⁻¹ (8.10 ng mL⁻¹) for the 2^nd one. In addition, the oxidation behavior of LED is discussed with a full investigation of the oxidized product using FT-IR and LC/MS. The fabricated sensor exhibits a good precision, selectivity and stability and was applied successfully for the determination of LED in its tablets and real rat plasma samples with a good recovery using a simple extraction technique.

Mixed convection has been one of the most interesting subjects of study in the area of heat transfer for many years. The entropy generation due to MHD mixed convection heat transfer in L-shaped enclosure being filled with Cu-water nanofluid and having an internal heating generation is explored in this investigation by the finite volume technique. Lid-motion is presented by both right and top parts of walls to induce forced convection and the cavity is under an inclined uniform magnetic field along the positive horizontal direction. The statistics concentrated specifically on the impacts of several key parameters like as the aspect ratio of the enclosure, Hartmann number, nanoparticle volume fraction, and heat source length/location on the heat transfer inside the L-shaped enclosure. Outcomes have been manifested in terms of isotherm lines, streamlines, local and average Nusselt numbers. The obtained results show that addition of nanoparticles into pure fluid leads to increase of heat transfer. The maximum value of local Nusselt pertaining to the heat source occurs when L = 0.1. Impacts of heat source size and location, internal heat generation absorption, angle of magnetic field on heat transfer and entropy generation are completely analyzed and discussed. The best configuration and values of important parameters are also presented using thermal performance criteria.

This contribution gives a numerical investigation of buoyancy-driven flow of natural convection heat transfer and entropy generation of non-Newtonian hybrid nanofluid (Al₂O₃-Cu) within an enclosure square porous cavity. Hybrid nanofluids represent a novel type of enhanced active fluids. During the current theoretical investigation, an actual available empirical data for both thermal conductivity and dynamic viscosity of hybrid nanofluids are applied directly. Numerical simulation have been implemented for solid nanoparticles, the volumetric concentration of which varies from 0.0% (i.e., pure fluid) to 0.1% of hybrid nanofluids. Heat and sink sources are situated on a part of the left and right sides of the cavity with length B, while the upper and bottom horizontal sides are kept adiabatic. The stated partial differential equations describing the flow are mutated to a dimensionless formulas, then solved numerically via the help of an implicit finite difference approach. The acquired computations are given in terms of streamlines, isotherms, isomicrorotations, isoconcentraions, local Began number, total entropy, local and mean Nusselt numbers. The data illustrates that variations of ratio of the average Nusselt number to the average Nusselt of pure fluid Nu_m⁺ is a decreasing function of Ha and φ, while e⁺ is an increasing function of Ha and φ parameters of hybrid nanofluid.

The current study treats the magnetic field impacts on the mixed convection flow within an undulating cavity filled by hybrid nanofluids and porous media. The local thermal non-equilibrium condition below the implications of heat generation and thermal radiation is conducted. The corrugated vertical walls of an involved cavity have and the plane walls are adiabatic. The heated part is put in the bottom wall and the left-top walls have lid velocities. The controlling dimensionless equations are numerically solved by the finite volume method through the SIMPLE technique. The varied parameters are scaled as a partial heat length (B: 0.2 to 0.8), heat generation/absorption coefficient (Q:− 2 to 2), thermal radiation parameter (R d: 0–5), Hartmann number (Ha: 0–50), the porosity parameter (ε: 0.4–0.9), inter-phase heat transfer coefficient (H*: 0–5000), the volume fraction of a hybrid nanofluid (ϕ: 0–0.1), modified conductivity ratio (k r: 0.01–100 …

r group is developing an ultra-compact neutron source based on inertial electrostatic confinement (IEC) fusion device for various applications at Kyoto University. This IEC device is configured from a titanium anode and a molybdenum cathode with diameters of 17 and 6 cm, respectively. A high-intensity neutron source operated in a stable pulse shape is mandatory to increase the system’s reliability. Applying a higher voltage is a straightforward way to increase the neutron yield from the system. However, a contradiction between the increase of the applied voltage and the reduction of the system size limits such a proposal. A three-stage feedthrough system is employed in the developed compact IEC to address this contradiction. A feedback control system was developed and applied to the input and output parameters, such as the applied voltage and the neutron yield, to increase its stability in long-term operation. Characterization of the developed system was performed by scanning the neutron yield as a function of applied voltage and cathode current. To date, a maximum neutron yield of 9.2 × 10⁷n·s^–1 at 6.4 kW (80 kV and 80 mA) has been obtained. A study of the feasibility of using the IEC system for neutron radiography was performed. Preliminary analysis of the resulting images showed there was good contrast between the sample and the background. The results suggest that optimization of the experimental parameters is needed to perform higher accuracy neutron radiography.