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In this paper, we investigate the analysis of Oldroyd 8-constant fluid flow with nanoparticle suspension via a porous media during the coating of wire is carried out. A constant magnetic field and electrically conducting fluid are considered. The governing equations thus obtained for the present model are converted to nonlinear differential equations using variables in dimensionless form. These equations are analytically solved. The influence of some parameters, like magnetic field parameter, porosity parameter, dilatant constant, pseudo-plastic constant and Brinkman number on velocity and temperature distributions are discussed graphically. For fluctuating viscosity, two models, Reynold’s and Vogel’s are considered. It is observed that the magnetic parameter and the Brinkman number increase, both temperature and velocity profiles show a retarding effect in both Reynold’s and Vogel’s models. [ABSTRACT FROM AUTHOR]

Based on the Multibeam backscatter data, Sub-bottom profiling and Remotely Operated Vehicle (ROV) dives, an attempt has been made to understand the spatial distribution of ferromanganese crusts and nodules on the West Sewell Ridge (WSR), Andaman Sea. Slope analysis of the multibeam data and echo type characters from sub-bottom profiles were used to identify favorable areas for crust and nodule occurrence and these areas were selected for detailed seafloor feature analysis using ROV videography. Further, histogram analysis of backscatter intensity revealed five boundary values and integrated these threshold values with ground truth observation from ROV videos identified crust dominated, crust and nodule dominated, the hard substrate with thin sediment cover, the hard substrate with thick sediment cover, and complete sediment covered seabed. The seafloor variation map prepared from the different geological classes identified shows that crust-dominated seabed is distributed in the eastern summit region while crust and nodule-dominated seabed in the western summit region of WSR. Further, the flanks of the WSR are covered with turbidity sediments and sediments derived from the slope failure and possess the least possibility of the occurrence of crusts and nodules on the flanks. [ABSTRACT FROM AUTHOR]

A theoretical and computational study of a magnetohydrodynamic and three-dimensional flow over a variable thickness sheet (slendering sheet) with Cattaneo-Christov heat flux is presented. The Williamson slip is considered at the modified boundary conditions. The Williamson slip model is employed which is representative of certain industrial polymers. The non-dimensional, transformed boundary layer equations for momentum, energy and species diffusion are transformed with appropriate boundary conditions. The non-linear ordinary differential equations (ODEs) are solved using the Runge-Kutta-Fehlberg integration method. Validation of the numerical solutions is achieved via bench marking with earlier published work. The influence of Williamson slip suppresses the momentum boundary layers thickness and enhances the thermal solutal boundary layer thickness. Graphically studied thermal relaxation parameter, wall thickness parameter, porosity parameter, Brownian motion and thermophoresis parameters. [ABSTRACT FROM AUTHOR]

In this paper, an unsteady magnetohydrodynamic (MHD) natural convection heat transfer flow of electrically conductive non-Newtonian Casson fluid over a stretching sheet through vertical porous plate with an influence of heat generation and viscous dissipation is investigated. Similarity transformations are employed to transform the governing partial differential equations into ordinary differential equations. The transformed equations are then solved numerically by Runge-Kutta and shooting methods. The heat flow characteristics for different values of the parameters namely Casson fluid parameter, unsteadiness parameter, Eckert number, heat generation parameter, permeability porous parameter and Prandtl number are studied and discussed in detail. The increase of permeability porous parameter reduces the velocity field and enhances the fluid temperature. The heat generation source leads to an increase in thermal boundary layer thickness. The higher viscous dissipative heat causes an increase in the fluid temperature. [ABSTRACT FROM AUTHOR]

A theoretical and computational study of a magnetohydrodynamic and three-dimensional flow over a variable thickness sheet (slendering sheet) with Cattaneo-Christov heat flux is presented. The Williamson slip is considered at the modified boundary conditions. The Williamson slip model is employed which is representative of certain industrial polymers. The non-dimensional, transformed boundary layer equations for momentum, energy and species diffusion are transformed with appropriate boundary conditions. The non-linear ordinary differential equations (ODEs) are solved using the Runge-Kutta-Fehlberg integration method. Validation of the numerical solutions is achieved via bench marking with earlier published work. The influence of Williamson slip suppresses the momentum boundary layers thickness and enhances the thermal solutal boundary layer thickness. Graphically studied thermal relaxation parameter, wall thickness parameter, porosity parameter, Brownian motion and thermophoresis parameters. [ABSTRACT FROM AUTHOR]

• Fabrication of flexible magnetoelectric PVDF/NiFe 2 O 4 nanofiber composite films. • Addition of NiFe 2 O 4 in PVDF plays an important role in transforming α to β phase. • PVDF/NiFe 2 O 4 films exhibit enhanced ferroelectric and magnetic properties. • DC EFM and MFM studies prove the multiferroic nature of the composite films. • PVDF/NiFe 2 O 4 nanogenerator and MME generators, generate a voltage of 10 V and 4.8 V. Flexible nanocomposite films of poly(vinylidene fluoride)(PVDF)/nickel ferrite (NiFe 2 O 4) fiber were made using solvent casting method. The NiFe 2 O 4 fibers with a diameter of 400 nm were synthesized initially by means of electrospinnig technique. Studies of XRD and FTIR confirmed the formation of both α and β phases in the composite films. The presence of α-phase was diminished with the incorporation of NiFe 2 O 4 and a maximum β-phase percentage (68%) was obtained. SEM and AFM analyses also demonstrated the transformation of the microstructures from α to β phase. The ferroelectric properties were tested with respect to NiFe 2 O 4 loading and the composite film with 10 wt% NiFe 2 O 4 exhibited a high P max value of 1.46 μC/cm2. VSM studies revealed the ferrimagnetic behaviour of the films and exhibited a maximum saturation magnetization value of 4.2 emu/cm3. Local ferroelectric properties were investigated through their domain switching behavior using dynamic contact electrostatic force microscopy (DC-EFM), and magnetic force microscopy (MFM) was used to analyze the magnetic properties. The magnetoelectric cross-coupling between ferroelectric and ferrimagnetic orderings is verified through the variations in ferroelectric parameters under different magnetic fields. Then a nanogenerator was fabricated using the composite films and generated an open circuit voltage of 10 V (peak-peak). Additionally, these films were made into magneto-mechano-electric (MME) generator, which could generate a 4.8 V (peak-peak) output voltage under a weak AC magnetic field of 10 Oe at 50 Hz. [ABSTRACT FROM AUTHOR]

The increasing popularity of wearable electronics has sparked interest in flexible energy harvesters as alternatives to conventional batteries. Flexible magnetoelectric (ME) composites, known for converting ambient magnetic field energy into useable power, are emerging as promising autonomous energy sources for integration into wearable devices. In this study, we prepared flexible (PVDF-AlN)–(NiO–CNF) based ME composites using two different methods: solution-casting and electrospinning techniques. The ME coupling was confirmed by measuring the ferroelectric and magnetic properties of the composite, and it was qualitatively characterized through the ME coupling coefficient. The electrospinning fibers-based ME composite exhibited an optimal value of 10.6 V/cm.Oe, significantly higher than the solution-casting films-based ME composite (1.3 V/cm.Oe) under a 1 kHz AC magnetic field (off-resonance condition). Subsequently, a flexible magneto-mechano-electric (MME) generator was designed using electrospun-derived material, harvesting a sinusoidal wave with a maximum output peak-to-peak voltage of 9.02 V. The generator displayed an optimal DC power density of 97 μW/m2 when exposed to a weak AC magnetic field of 6 Oe at a frequency of 50 Hz. Consequently, it holds great promise as an efficient autonomous power supply for medical sensing and various miniature electronic applications. [ABSTRACT FROM AUTHOR]

A two-step synthesis method was used to prepare a flexible PVDF/ZnFe 2 O 4 multiferroic nanocomposite film. ZnFe 2 O 4 nanofibers synthesized using electrospinning technique were incorporated into a PVDF matrix to form PVDF/ZnFe 2 O 4 composite films through the solution-casting process. XRD patterns confirmed the formation of the polar β-phase in films, which is responsible for ferroelectricity. The percentage of the β-phase, calculated by FTIR analysis, reached 88% with the incorporation of ZnFe 2 O 4 in PVDF. The transformation of α to β-phase microstructure were examined using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The dielectric constant and tangent loss of the composites with respect to ZnFe 2 O 4 loading were measured. The dielectric constant increase with the increasing concentration of ZnFe 2 O 4 , and a maximum value of 30 was obtained for a ZnFe 2 O 4 concentration of 15 wt%. Ferroelectric properties were analyzed by taking into consideration the domain switching behavior, which was investigated by dynamic contact electrostatic force microscopy (DC-EFM), whereas the magnetic properties were analyzed using magnetic force microscopy (MFM). The as-synthesized composite films were further used to fabricate a nanogenerator, which was capable of generating up to 7 V (peak–peak) as a maximum open circuit voltage for a 15 wt% ZnFe 2 O 4 -loaded film at 1.5 N of applied force. In addition, the nanogenerator delivered an output power of 4 μW at a load resistance of 500 kΩ, and the results were compared with previous results. • Fabrication of flexible multiferroic PVDF/ZnFe 2 O 4 nanofiber composite films. • Addition of ZnFe 2 O 4 in PVDF plays an important role in transforming α to β phase. • PVDF/ZnFe 2 O 4 films exhibit enhanced dielectric and ferroelectric properties. • DC EFM and MFM studies prove the multiferroic nature of the composite films. • PVDF/ZnFe 2 O 4 nanogenerator generates a voltage of 7 V and power of 4 μW. [ABSTRACT FROM AUTHOR]

This work is devoted to investigating the influence of diffusion thermo effect on hydromagnetic heat and mass transfer oscillatory flow of a micropolar fluid over an infinite moving vertical permeable plate in a saturated porous medium in the presence of transverse magnetic field and chemical reaction. The dimensionless equations are solved analytically using perturbation technique. The effects of the various fluid flow parameters entering into the problem on the velocity, microrotation, temperature and concentration fields within the boundary layer are discussed with the help of graphs. Also the local skin-friction coefficient, the wall couple stress coefficient, and the rates of heat and mass transfer coefficients are derived and shown in graphs. Comparison of the obtained numerical results is made with existing literature and is found to be in good agreement. [ABSTRACT FROM AUTHOR]