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The investigation of the adsorption potential of the Jordanian calcinated bentonite to remove phosphate ions from aqueous solutions whether they are synthetic or actual samples was studied in this article, The temperatures for calcination ranged from (100°C–900°C). The effectiveness of calcining bentonite’s ability to remove phosphate ions was investigated under various conditions, including initial concentration of phosphate ions, calcinations, temperature, particle size, pH levels, adsorbent dose, and contact time. Using pseudo-first-order, pseudo-second-order rates and intraparticle diffusion models the kinetic studies were carried out. The R2values indicated that pseudo-second- order rather than pseudo-first-order provided a better fit for the phosphate transport. The activation energy for the removal for both synthetic and actual materials was computed, and it was found to be 8.93 and 12.120 kJ/mol, respectively, this shows that physisorption may have happened. The rate of phosphate ion uptake was also investigated using intraparticle diffusion model at different variables (temperature, particle size, agitation, and pH values), and both particle diffusion (Dp) and film diffusion (Df) coefficients were predicted, with the results indicating that film diffusion (Df) is the rate determining step.

This manuscript merits at examining of an embedded orthogonal plate inside porous domain exposed to uniform heat influx to elaborate on how micro polar fluid factors and permeability characteristic affect the local skin friction, heating rate, and angular velocity inside boundary layer. The plate is subjected to forced convective micro polar fluid influx under steady, incompressible, and viscous circumstances. To facilitate dependable numerical solution, similarity approach is implemented to mutate set of coupled governing equations relevant to the adopted study into a constrained dimensionless differential equations. Computational analysis has been executed hiring Runge-Kutta scheme by Matlab function bvp4cto settle the governing equations. Study's results are highlighted graphically the impact of micro polar fluid factors on the local skin friction, heating rate, and angular velocity curves. High degree of acceptability of present findings compare with prior research results. It is found that the rising of Darcy parameter drives to decrease linearly both heating rate and local skin friction. Among the examined factors, the benchmark parameter of decreasing skin friction is the porosity. Additionally, it is found that an increasing of Prandtl number and micro rotation element lead to enhance Nusselt number. Once curves of micro rotation are interfered at certain distance from the plate due to increase in porosity, Darcy, Forchheimer's, and microelement rotation, the micro rotation curves are inverted.

The effectiveness of different methods, schemes, algorithms, and approaches is of substantial challenging problems in numerical modeling of transport phenomena. In the present paper, a lid-driven cavity problem is modeled via two basically different approaches of spatial discretization: collocated and staggered. The non-dimensionalized governing equations are semi-discretized by using a finite volume approach. Then, the full discretization is performed in each of collocated and staggered grids, separately. Upwind and central difference schemes are implemented in order to discretize the convective and diffusion terms of equations, respectively. After mesh independency study, the performances of collocated and staggered grids in comparison with the reference benchmark are presented. Next, the effectiveness of the first and the second order upwind schemes are presented, as well as different coupling algorithms of SIMPLE, SIMPLEC, and SIMPLER. Finally, an overall comparison of the methods is provided and acceptable agreements with benchmark are attained.

Plasmonic devices, consisting of nanoparticle monolayers, are conveniently fabricated by deposition techniques, wherein thermodynamics often favor the particle shape to be close to hemispherical. The present work investigates plasmon modes in Ag nanohemispheres (NHSs) using s- and p-polarized incident radiation at varying angles. The Ag NHSs, immobilized on nanoposts, resembling mushroom structures, allow for reduced substrate coupling and convenient resolution of the modes. Additionally, the modes are studied by in situ extinction acquisitions during nanoparticle synthesis and elucidated by numerical simulations. It is revealed that the broken symmetry by asymmetric particle shape leads to dipolar modes parallel and normal to the base, which are significantly different in terms of energy, excitation dependence on polarization, and particle–particle as well as particle–substrate couplings. In particular, the major parallel mode offers distinct advantages in plasmonics applications over nanospheres. For example, its strong substrate coupling may benefit thin film photovoltaics by efficient light coupling. Higher field concentrations are induced at the sharp edges of a NHS that may enhance hot electron injection in a photocatalyst. Unlike in a spherical dimer, where the field intensity peaks in the middle of the gap, the maximum field in a NHS dimer gap occurs on the metal surface (i.e., at the edges), overlaying with the chemical enhancement. Hence, a higher surface enhancement factor can be achieved in Raman scattering.

Williamson fluid flux and heat transfer characteristics over horizontal plate via a saturated porous medium at constant surface temperature are examined in this study to determine the impact of forced viscous dissipation. The flow is modeled using a Darcy-Forchheimer-Brinkman model based on conservation laws and associated governing equations. Using appropriate dimensionless variables, the modeled governed equations are transformed into dimensionless differential forms. The higher constrained coupled non-linear differential equations have been reduced to the first order differential equations to find a reliable numerical solution. The Runge-Kutta method and the built-in Matlab function bvp4c are applied in the shooting method to produce a numerical solution. The impact of λx, ϵ, ζx, βxon the velocity profile, temperature, shear stress, and skin friction are illustrated graphically. It is found that the increasing of the Darcy number leads to enhance both velocity and shear stress while the temperature and the Nusselt number are diminished inside the boundary layer. Additionally, it is found that the raising Williamson's parameter causes the temperature to rise while decreasing velocity, shear stress, heat transfer coefficient, and Nusselt number inside the boundary layer. The method applied in the current work is supported by earlier research.

Genome-wide association studies (GWASs) show that genetic factors contribute to the risk of severe coronavirus disease 2019 (COVID-19) and blood analyte levels. Here, we utilize GWAS summary statistics to study the shared genetic influences (pleiotropy) between severe COVID-19 and 344 blood analytes at the genome, gene, and single-nucleotide polymorphism (SNP) levels. Our pleiotropy analyses genetically link blood levels of 71 analytes to severe COVID-19 in at least one of the three levels of investigation—suggesting shared biological mechanisms or causal relationships. Six analytes (alanine aminotransferase, alkaline phosphatase, apolipoprotein B, C-reactive protein, triglycerides, and urate) display evidence of pleiotropy with severe COVID-19 at all three levels. Causality analyses indicate that higher triglycerides levels causally increase the risk of severe COVID-19, thereby providing important support for the use of lipid-lowering drugs such as statins and fibrates to prevent severe COVID-19.

This paper presents an unconventional tri-rotor unmanned aerial vehicle (UAV) design that only employs three brushless motors with three fixed pitch propellers for propulsion and flight control. No additional mechanics for dynamically tilting motor(s), found on existing tricopters, are used. The dynamic model of the proposed system is developed. Then a control strategy to control the stability and manoeuvring of the UAV is presented. The control strategy is achieved by only manipulating the rotational speeds of the propellers at each rotor. Two of the rotors rotate in the same direction while the third rotates in the opposite direction. The control methodology is novel compared to other systems that require either coaxial rotors or an extra servo motor to control the yaw of the UAV. Results show that the proposed design achieved stable flight with minimal position-attitude cross control effect. The fixed nature of the rotors in the proposed design, reduced mechanical requirements and cost compared to existing vehicles of its type.

Homogeneous negative index materials have been introduced as an alternative to conventional metamaterials designs. Based on direct experimental evidence, we demonstrate that the magnetic semiconductor, Cr-doped indium oxide, possesses a negative refractive index near 28.0$~\mu\hbox{m}$ . This effect is based on the coexistence of the magnon mode with the plasmonic mode, with simultaneous negative permeability and permittivity responses. Thin films of In$_{2-x}$ Cr$_{\rm x} O_{3}$ are fabricated, and the magnetic measurements clearly demonstrate ferromagnetism with a high saturation magnetization and a Curie temperature which is much higher than room temperature. The refractive index is extracted from combined transmittance and reflectance data and is compared with the theoretical prediction. Moreover, a direct experimental method is used to demonstrate negative refraction in this material.

Kinetics of oxidation of L‐cysteine by CoIIIand FeIIIcomplexes based on α‐ and γ‐diimine Schiff base ligands were studied in aqueous solution. Pairs of transand cisisomers of the metal complexes were used in the studies. Kinetic measurements were performed at 25 °C and constant pH and ionic strength under pseudo‐first order condition, in which the concentration of cysteine was around two orders of magnitude greater than that of the metal complex. The observed rate constant was obtained by following the change in absorbance of the reaction mixture with time at a predetermined wavelength. The overall rate constant and order of the reaction with respect to cysteine and metal complex were determined. For both metal ions studied, the oxidation rate constant for the transisomer was higher than that for the cisisomer. This was attributed to the contribution of the steric factor and the transeffect. The effects of substituents and the nature of the metal ion on the reaction rate are discussed.

Effects of the initial vibrational and rotational energy of a diatomic molecule on reaction rates of atom-diatomic molecule reactions have been studied using classical trajectory calculations. The reaction probabilities, cross-sections and rate constants were calculated using the three-dimensional Monte-Carlo method. Equations of motion, which predict the positions and momenta of the colliding particles after each step in the trajectory, have been integrated numerically by the Runge-Kutta-Gill and Adams-Moulton methods. Morse potential energy surfaces were used to describe the interaction between the atom and each atom in the diatomic molecule. Several atom-diatomic molecule systems were studied. Variation of the reaction cross-section with both vibrational and rotational quantum numbers has been studied. For all systems studied, it was found that the cross-section increases with the vibrational quantum number. However, the effect of rotational quantum number on cross-section varies from one system to another.

A series of new cobalt(III)-, iron(III)-, and chromium(III)-based complexes of the general formula [M(NnO)2Cl] (NnO: N-salicylidene(X)amine and sodium N-(4-sulfonatosalicylidene(X)amine)) (X = cyclohexyl and 1-naphthyl) was prepared and characterized. Some of the isolated complexes have been evaluated as catalysts for the oxidation of L-cysteine. Preliminary results show that the rate of oxidation of L-cysteine is influenced by the nature of the metal center, the geometry of the complex, the auxiliary substituents, and the backbone of the ligand.

The synthesis of a new series of transand racemic cisisomers of cobalt(III)‐, iron(III)‐, and chromium(III)‐based complexes with the α‐ and γ‐diimine Schiff base ligands, N,N′‐bis(X)‐2,3‐butandiimine and N,N′‐bis(X)‐1,2‐phenyldiimine (X = cyclohexyl, 2‐isopropylphenyl, 1‐naphthyl) is described. To confirm the identity of the complexes prepared in the present study, a variety of techniques including elemental analysis, magnetic susceptibility, infrared‐, mass‐ (EI), and UV/Vis‐ spectroscopy have been utilized. Some of the isolated complexes have been evaluated as catalysts for the oxidation of L‐cysteine. Preliminary results showed that the metal atoms, geometry of the complexes, auxiliary substituents, and the backbone of the ligand influenced the rate of oxidation reaction.

Classical trajectory calculations for various atom-diatomic molecules were preformed using the three-dimensional Monte Carlo method. The reaction probabilities, cross-sections and rate constants of several systems were calculated. Equations of motion, which predict the positions and momenta of the colliding particles after each step, have been integrated numerically by the Runge-Kutta-Gill and Adams-Moulton methods. Morse potential energy surfaces were used to describe the interaction between the atom and each atom in the diatomic molecules. The results were compared with experimental ones and with other theoretical values. Good agreement was obtained between calculated rate constants and those obtained experimentally. Also, reasonable agreement was observed with theoretical rate constants obtained by other investigators using different calculation methods. The effects of the temperature, the nature of the colliding particles and the thermochemistry were studied. The results showed a strong dependence of the reaction rates on these factors.

This article examines the Greek epigraphic material kept at the Mu’tah University Museum. It is a collection composed of 23 inscriptions, 20 of them unpublished, which with one exception (no. 1 from Qasr el-Hallabat) originate from the Southern Kerak plateau, mainly from the sites of Ader, Mu’tah, Iraq, Nakhl and Maḥaiy. Apart from a dedication to Artemis (second century AD), all the remaining inscriptions are funerary and date between the late fourth and late sixth century AD. The present epigraphic material not only adds 20 new epitaphs to those hitherto known from Moab, but offers also an interesting onomasticon.

Kinetics of oxidation of L-cysteine by pairs of trans and racemic cis isomers of cobalt(III) and iron(III) based transition metal complexes have been studied in aqueous solution. Kinetics measurements were run under pseudo first order conditions in which the concentration of cysteine is between one and two orders of magnitude greater than that of the isomers of the transition metal complex. The orders of the reaction with respect to both cysteine and the isomer were determined.

The ideal conservative treatment for lower limb oedema would be one that provided intermittent compression whilst allowing the patient to remain mobile. In this article we describe the development of a pneumatic ambulatory compression device that utilizes the patient's weight applied, during walking, to air cells under the foot to provide compression to the ankle and calf. In volunteer studies this device typically produced a cycle of interface pressure changes from 20 to 45-50 mmHg on the lower calf and 20 to 35-40 mmHg on the upper calf.