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Abstract\nCULMINATIONSThe ureter typically experiences a frequency of one to five peristaltic contractions per minute. However, it is important to note that these contractions can be disrupted by various physical and mechanical irritants. Ionic contents in the urine make it electrically conducting and responsive to electromagnetic body forces. MHD can be deployed in bio magnetic therapy to control or mitigate symptoms associated with peristaltic pumping in the urinary system.  This article therefore focuses on the hydromagnetic effects on flow patterns of urine with debris (monoliths). The mechanism of urine flow is largely coordinated by the kidneys. The flow inside the ureter is interrupted by microliths, which are generated by the sedimentation of excretory products. To simulate this, a two-phase formulation is adopted, comprising the electromagnetic urological viscous fluid phase and the particulate phase for solid grains. The peristaltic propulsion of two-phase liquid in the ureter is simulated as a sinusoidal wave propagation of incompressible non-Newtonian fluid. The Williamson viscoelastic model is deployed for the rheology. Heat transfer is also included with Soret thermo-diffusion and viscous heating effects. Long wave and low Reynolds number approximations are employed based on lubrication theory. The mass, momentum, energy and concentration conservation equations with associated boundary conditions are rendered non-dimensional via appropriate scaling transformations. A numerical solution is achieved via BVP4C MATLAB quadrature.  Graphical visualizations of the velocity, temperature and concentration (solid grains) are given for the influence of suspension parameter (ζ), Hartmann number (M), Prandtl number (Pr), Weissenburg number (We), particle volume fraction (C), Eckert number (Ec), Soret number (Sr), Schmidt number (Sc). The novelty of the present work is therefore the simultaneous consideration of a generalized two-phase model, wall slip, non-Newtonian characteristics, cross diffusion, viscous dissipation, mass diffusion, magnetic body force and curvature effects in peristaltic urological transport, which has not been undertaken previously. The detailed simulations reveal that the flow velocity is reduced due to the presence of solid particles and the channel curvature, in comparison to the flow in an unobstructed channel devoid of solid particles. Enhancing the hydrodynamic slip parameter speeds up the movement of particles and fluid near the channel walls, boosts wall skin friction, raises pressure difference in the pumping area, and amplifies bolus magnitudes.The rise in peristaltic pumping results in a reduction in solid particle concentration, which is significant phenomena.This theoretical approach may aid in treating conditions such as Urinary Tract Infections (UTIs). The computations effectively demonstrate that significant manipulation of urological pumping characteristics can be achieved with an electromagnetic field. Some new features of two-phase ureteral dynamics are highlighted as relevant to magnetic therapy techniques, which may be beneficial to clinicians.A detailed new formulation is given for magnetohydrodynamic (MHD) two-phase Williamson non-Newtonian ureteral transport with mass diffusion, Soret cross diffusion, viscous heating and peristaltic wave propulsion.We compute numerically the pressure gradient, skin friction, Nusselt number, and wall shear stress in a planar channel with flexible walls, which serves as a model for the ureter under a transverse magnetic field.We also investigate the impact of Hartmann number and Weissenberg non-Newtonian number on fluid and particle phase velocities.The present work reveals some interesting insights into electromagnetic ureteral peristaltic multi-phase non-Newtonian thermo-solutal transport phenomena via extensive visualization.There is a strong suppression in the ureteral fluid phase velocity for greater magnetic field confirming the excellent flow control abilities of Magnetic Ureteral Therapy (MUT).A detailed new formulation is given for magnetohydrodynamic (MHD) two-phase Williamson non-Newtonian ureteral transport with mass diffusion, Soret cross diffusion, viscous heating and peristaltic wave propulsion.We compute numerically the pressure gradient, skin friction, Nusselt number, and wall shear stress in a planar channel with flexible walls, which serves as a model for the ureter under a transverse magnetic field.We also investigate the impact of Hartmann number and Weissenberg non-Newtonian number on fluid and particle phase velocities.The present work reveals some interesting insights into electromagnetic ureteral peristaltic multi-phase non-Newtonian thermo-solutal transport phenomena via extensive visualization.There is a strong suppression in the ureteral fluid phase velocity for greater magnetic field confirming the excellent flow control abilities of Magnetic Ureteral Therapy (MUT). [ABSTRACT FROM AUTHOR]

Hemodynamics in stenosed arteries is complex, including turbulence, recirculation, and vortices, which can further worsen the disease. This study provides an overview of blood flow characteristics in stenosed arteries, focusing on flow physics, stenosis geometry, and severity. This present article examines the impact of heat and mass exchange on blood flow in arterial stenosis, taking into account chemical processes, magnetic fields, and thermal radiation. The features of vital fluid (blood) in the constricted arterial tube are examined by taking blood as Newtonian fluid in the arterial stenosis region. The continuity (mass), momentum, and concentration equations are solved using a finite difference approach with the help of appropriate boundary conditions. Solutions have been established for axial velocity, temperature, and concentration equations with variable parameters in blood circulation. It is noticed that an enhancement in the Reynolds number indicates more disorder in the velocity of the blood flow near the downstream area of cholesterol or plaque deposition. The temperature profile induced is stronger nearer to the arterial complaint wall downstream of stenosis. These findings for RBC's flow in stenosis-contained arteries have significant advantages in terms of understanding the disease mechanisms, developing accurate computational models, and identifying effective treatment strategies for patients. [ABSTRACT FROM AUTHOR]

A mathematical study is described to examine the concurrent influence of thermal radiation and thermal wall slip on the dissipative magnetohydrodynamic electro‐osmotic peristaltic propulsion of a viscous nanoliquid in an asymmetric microchannel under the action of an axial electric field and transverse magnetic field. Convective boundary conditions are incorporated in the model and the case of forced convection is studied, that is, thermal and species (nanoparticle volume fraction) buoyancy forces neglected. The heat source and sink effects are also included and the diffusion flux approximation is employed for radiative heat transfer. The transport model comprises the continuity, momentum, energy, nanoparticle volume fraction, and electric potential equations with appropriate boundary conditions. These are simplified by negating the inertial forces and invoking the Debye–Hückel linearization. The resulting governing equations are reduced into a system of nondimensional simultaneous ordinary differential equations, which are solved analytically. Numerical evaluation is conducted with symbolic software (MATLAB). The impact of different control parameters (Hartmann number, electro‐osmosis parameter, slip parameter, Helmholtz–Smoluchowski velocity, Biot numbers, Brinkman number, thermal radiation, and Prandtl number) on the heat, mass, and momentum characteristics (velocity, temperature, Nusselt number, etc) are presented graphically. Increasing Brinkman number is found to elevate temperature magnitudes. For positive Helmholtz–Smoluchowski velocity (reverse axial electrical field) temperature is strongly reduced, whereas for negative Helmholtz–Smoluchowski velocity (aligned axial electrical field), it is significantly elevated. With increasing thermal slip, nanoparticle volume fraction is also increased. Heat source elevates temperatures, whereas heat sink depresses them, across the microchannel span. Conversely, heat sink elevates nanoparticle volume fraction, whereas heat source decreases it. Increasing Hartmann (magnetic) parameter and Prandtl number enhance the nanoparticle volume fraction. Furthermore, with increasing radiation parameter, the Nusselt number is reduced at the extremities of the microchannel, whereas it is elevated at intermediate distances. The results reported provide a good insight into biomimetic energy systems exploiting electromagnetics and nanotechnology, and, furthermore, they furnish a useful benchmark for experimental and more advanced computational multiphysics simulations. [ABSTRACT FROM AUTHOR]

Flame retarding co-solvents triphenyl phosphate (TPP) and dimethyl methylphosphonate (DMMP) were incorporated into a standard binary LiPF6/ethylene carbonate (EC)/Ethyl methyl carbonate (EMC) electrolyte with and without the anode solid electrolyte interface (SEI) film forming additive, lithium bis(oxalato)borate (LiBOB). Thin-film silicon/Li cells were cycled with the different electrolytes. The standard electrolyte has poor cycling performance losing ~ 50% of the initial capacity during the first 50 cycles. Electrolytes containing TPP and DMMP show comparable cycling performance to the standard electrolyte. Incorporation of LiBOB into the standard electrolyte or the standard electrolyte containing flame retarding co-solvents results in improved cycling efficiency and capacity retention. Ex-situ analysis via X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) provides insight into the role of LiBOB in the improved cycling performance and SEI structure and composition. [ABSTRACT FROM AUTHOR]