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Magnetohydrodynamics (MHD) have numerous engineering and biomedical applications such as sensors, MHD pumps, magnetic medications, MRI, cancer therapy, astronomy, cosmology, earthquakes, and cardiovascular devices. In view of these applications and current developments, we investigate the magnetohydrodynamic MHD electro-osmotic flow of Casson nanofluid during peristaltic movement in a non-uniform porous asymmetric channel. The effect of thermal radiation, heat source, and Hall current on the Casson fluid peristaltic pumping in a porous medium is taken into consideration. The effect of chemical reactions is also considered. The mass, momentum, energy, and concentration equations were constructed using the proper transformations and dimensionless variables to make them easier for non-Newtonian fluids. A lubricating strategy is used to make the system less complicated. The Boltzmann distribution of electric potential over an electric double layer is studied using the Debye–Huckel approximation. The temperature and concentration equations are addressed using the homotopy perturbation method (HPM), while the exact solution is determined for the velocity field. The study examines the performance of velocity, pressure rise, temperature, concentration, streamlines, Nusselt, and Sherwood numbers for the involved parameters using graphical illustrations and tables. Asymmetric channels exhibit varying behavior, with velocity declining near the left wall and accelerating towards the right wall while enhancing the Casson fluid parameter. The pumping rate boosts in the retrograde region due to the evolution of the permeability parameter value, while it declines in the augment region. The temperature profile optimizes as the value of the heat source parameter gets higher. The concentration profile significantly falls as the chemical reaction parameter rises. The size of the trapped bolus strengthens with a spike in the parameter for the Casson fluid.

Thick-target PIXE analysis was applied to the study of electrokinetic soil remediation technique. In order to simulate radioactive soil contamination by ¹³⁷Cs, salt of stable cesium was mixed with soil samples. These soil samples were subjected to electrolysis for up to 36 hours with a field gradient of ≈ 1-3 V/cm. After the electrolysis, we measured the distribution of Cs concentration in the soil along the electrolysis cell by PIXE analysis. LX-rays of cesium were used for the analysis. The Cs concentrations in the drain water sampled from the cathode well were also evaluated. After the electrolysis the migration of cesium from the anode to the cathode was clearly observed. Water supply into the anode well enhanced the removal rate. We found that the main driving force of the migration of Cs⁺ observed in this work was not electrophoretic migration, but electroosmotic flow in the soil samples. Owing to the spectral interference by major metallic elements in the soil, the minimum detectable concentration of cesium by the present method was limited to ≈ 800 ppm.

This study aims to investigate the thermodynamic analysis for electroosmotic flow of ${\mathrm{\text{Fe}}}_3{\mathrm{\text{O}}}_4$–${\mathrm{\text{Cu/H}}}_2\mathrm{\text{O}}$ hybrid nanofluid in the presence of peristaltic propulsion. Hybrid nanofluid is an aqueous solution of copper and iron oxide nanoparticles. Effects of electric field, Ohmic heating, magnetic field, viscous dissipation, heat sink/source and mixed convection are also considered. The Debye–Hückel and lubrication approach has been adopted to perform mathematical modeling. The resulting differential equations are numerically solved by employing the Shooting method. Analysis has been presented for irreversibility rate and heat transfer for the flow of hybrid nanoliquid. Results reveal that the addition of nanoparticles reduces the temperature and entropy generation of hybrid nanoliquid. Heat transfer rate enhances by improving Joule heating and electroosmotic parameters. An increase in Helmholtz–Smoluchowski velocity and Hartmann number decrease the velocity of fluid. Thermal performance of hybrid nanofluid (${\mathrm{\text{Fe}}}_3{\mathrm{\text{O}}}_4$–${\mathrm{\text{Cu/H}}}_2\mathrm{\text{O}}$) is more noticeable in comparison with conventional mono nanofluid (${\mathrm{\text{Fe}}}_3{\mathrm{\text{O}}}_4$–${\mathrm{\text{H}}}_2\mathrm{\text{O}}$) and base fluid (${\mathrm{\text{H}}}_2\mathrm{\text{O}}$).

This investigation articulately addresses the role of gold nanoparticles in medical sciences from a different perspective. Aiming to highlight the significant usage of nanoparticles, four different types such as spherical, platelets, cylindrical and brick-like nanoparticles are brought into consideration with the main focus to achieve maximum heat enhancement. This motivation leads to mathematically formulating an electroosmosis blood flow. Casson fluid is treated as physiological fluid through an asymmetric microchannel. The nonlinear term of radiative heat flux is added on the right-hand side of the heat equation to report the impact of radiation which is beneficial in skin diseases. A closed-form solution is achieved with the help of physical approximation. Moreover, analytical expressions for velocity distribution, temperature field, shear stress, heat transfer rate and pressure gradient have been provided. The expression of stream function is also presented and the trapping phenomena are discussed. Besides studying the tremendous capacity of gold particles to enhance the heat transfer rate for targeting the maligned tissues as a prime objective, the current survey will also assist readers to explore the other similar metallic particles which can effectively be used as an alternative.

The study of electro-osmosis, peristalsis and heat transfer with numerous slips, such as velocity slip, thermal slip and concentration slip, may be used to construct biomimetic thermal pumping systems at the microscale of interest in physiological transport phenomena. A mathematical model has been developed to investigate magnetohydro-dynamics non-Newtonian (Carreau fluid) flow induced by the forces to produce a pressure gradient. The walls of the microchannels erode as they expand. The Poisson and Nernst–Planck equations are used to model electro-osmotic processes. This procedure results in Boltzmann circulation of the electric potential across the electric double layer. The governing equations are simplified by approximations such as a low Reynolds number and a long wavelength. The ND Solver in Mathematica simulates and compares simplified coupled nonlinear governing equations. We investigate novel physical parameters affecting flow, heat transfer and pumping. Additionally, a fundamental peristaltic pumping phenomenon known as trapping is graphically provided and briefly discussed. The model’s findings show that the velocity increases as the electric field intensifies, implying that electro-osmosis may improve peristaltic flow.

Activation energy and thermal radiation as a means of heat transfer are significant and fascinating phenomena for scientists and researchers because of their significance in cancer treatment. As a result, heat kills cancer cells and shrinks tumors, making hyperthermia therapy a cutting-edge cancer treatment. This paper examines the peristaltic motion of a Johnson–Segalman nanofluid across an asymmetric pliable microchannel under the impact of activation energy. We obtained the governing equations for the non-Newtonian nanofluid. Partial differential equations (PDEs) are reduced to ordinary differential equations (ODEs) under the assumption of large wavelengths and tiny Reynolds number assumptions. The flow patterns and trapping phenomena were numerically generated using the NDSolve command of the computational mathematical software Mathematica. The influence of important liquid parameters was examined with graphical representations of the results. The current study reveals an enhancement in the heat generation parameter, an enhancement in the temperature and a reduction in the concentration.

Peristalsis of non-Newtonian nanofluid via a non-uniform conduit has several applications in physiology and industry. This study proposes a mathematical model as well as exploration of the impacts of entropy generation for peristalsis of magneto nanofluid with temperature-dependent thermal conductivity via an expanding asymmetric channel. Buongiorno’s model for study of nanofluid flow has been adopted. Rheological aspects are accounted using the Carreau–Yasuda model due to its experimentally validated significance. Impacts of applied electric and magnetic fields have been taken into account. Thermophoresis, ohmic heating, viscous heating and Brownian motion effects are incorporated in the model. Numerical method is used via NDSolve in Mathematica after implementing the lubrication approach and Debye–Huckel linearization. The effects of embedded parameters on the flow, heat transfer, entropy generation and Bejan number are studied using graphical depictions. Outcomes indicate that a rise in electroosmotic parameter enhances heat transfer rate, whereas it reduces entropy generation and mass transfer rate at the boundary. Therefore, this study can provide basics to study nanofluidic systems which has applications in drug delivery. Increasing trends for temperature, heat transfer rate and entropy generation, while declining trends in the concentration of the particles are noted for higher joule heating.