Influence Of Magnetic Flux Research Articles

Numerical exploration of MHD bioconvective Williamson-Maxwell nanoliquid flow due to an exponentially elongated porous sheet

This research delves into the intriguing realm of non-Newtonian fluids in conjunction with microorganisms, presenting a mathematical model tailored to analyze heat and mass transfer within Williamson-Maxwell nanofluids hosting gyrotactic microbes. The study investigates how these fluids behave under the influence of multiple factors such as magnetic fields, thermal radiation, chemical reactions, and dissipation effects. Employing a set of similarity invariants, the governing equations are transformed into ordinary differential equations, which are then solved using a fourth-order R-K scheme. The findings, presented graphically, offer insights into various flow parameters and are complemented by pertinent physical explanations. The influence of magnetic flux ([Formula: see text]), Buoyancy ratio ([Formula: see text]), Peclet number ([Formula: see text]), and Schmidt number ([Formula: see text]) on various physical parameters are shown graphically. Notably, the research reveals that while increasing the external magnetic field impedes fluid motion, it enhances thermal and density layers. Additionally, a higher bioconvective Schmidt number is shown to reduce microbial density. These observations hold significant implications for applications involving nanofluids and microorganisms across biomedical, pharmaceutical, biofuels, and other sectors. Overall, this study contributes valuable knowledge to the understanding and potential utilization of complex fluid systems in diverse industrial contexts.

Behaviour of RC Beam Using Concrete Mixed With Magnetically Treated Water

The most important challenge for concrete construction is to improve the performance of concrete. In the last two decades, in Russia and China, a new technology, called magnetic water technology, has been used in making concrete. As per this technology, by passing water through a magnetic field, some of its physical properties tend to change and, as a result of such changes, the number of molecules in the water cluster decreases from 13 to 5 or 6, which cause a decrease in the surface tension of water, with an improvement in the workability and strength of concrete. Magnetic treatment of water increases the ion solubility and pH. The influence of magnetic flux changes the mode of calcium carbonate precipitation such that circular disc-shaped particles are formed rather than the dendritic (branching or tree like) particles observed in non-treated water. This technique is mostly used for the softening of water and, for the first time in this research, it has been adopted by the scientists for the production of concrete with improved strength. Some researchers hypothesize that magnetic treatment affects the nature of hydrogen bonds between water molecules which increases the pH and softens the water.

Properties and influence of magnetic fields on iron particles of anisotropic magnetorheological elastomers

The magnetorheological elastomer (MRE) is an intelligent material whose mechanical properties can be rapidly adjusted under a magnetic flux density. This material’s mechanical properties change due to the interaction between the iron particles inside the material. Understanding the influence of magnetic flux on iron particles in MRE materials is essential. Studies have proven that the distance and angle of inclination between iron particles significantly affect the magnetic flux density and the interaction force between the particles. Therefore, the distribution of iron particles substantially affects the material’s properties. However, understanding magnetic flux through magnetic particles is necessary to improve the material’s mechanical properties and to design magnetic field systems in systems using the materials. This study maps three problems affecting magnetic flux density to the properties of MRE. First, the mechanical characteristics of the MRE were presented in the frequency, amplitude, magnetic flux density, and magnetic flux inclination domains relative to the particle chain. Next, the influence of the magnetic flux on the particle chain was investigated based on the dipole interaction model and the magnetic force on iron particles. The finite element method also explored the magnetic flux distribution in the MRE material. Finally, the response of the single-degree-of-freedom damping system is tested experimentally. The results show that the influence of the magnetic flux on the iron particles in the MRE material is significant. The research results aim to improve the mechanical properties of MRE materials.

Morphological Effects on Natural Convection Heat Transfer of Magnesium Ferrite Ferrofluid

This investigation intends to analyze the influence of nanoparticles morphology on the magnetic flux dependent thermo-physical properties and magnetohydrodynamic free convection heat transfer performance of water-based magnesium ferrite ferrofluid under various volume fractions. The thermo-physical parameters of the ferrofluid suspended with cube shaped particles are examined at 25 °C using KD2 pro thermal analyzer, Ostwald viscometer and specific gravity bottle under magnetic flux. The free convection heat transfer is obtained using heat pipes assisted cubical enclosure. Without the influence of magnetic flux, the thermal conductivity of the ferrofluid was improved by a maximum of 12.75% at a volume fraction of 0.15%. At the same time, the maximum viscosity and density were raised by 32.92% and 6.11% at a volume fraction of 0.20% in comparison with water. Under the influence of 350 Gauss, thermal conductivity, and viscosity of ferrofluid enhanced by 21.81% and 37.41% while the density decreased by 4.91%. It was revealed that the addition of cube-shaped magnesium ferrite particles in ferrofluid improved the thermo-physical properties. The optimum concentration for maximum heat transfer is reduced to 0.025% with the use of cube shaped particles compared to other types of nanoparticles reported in previous studies.

Charging Our Electrical Devices in Anywhere and at Any time

Being able to charge electronic devices anywhere is a modern-day problem. That said, ‘Made in China’ external charging devices can solve this problem to some extent. However, these de- vices are often poor quality and can be a fire hazard. To address this issue, the author suggests using an electromagnetic spread spectrum, which is highly related to harvesting electrical energy from clean, renewable energy sources, and then transmitted to charge all types of electrical devices. By applying this author’s proposed probability-random variables assignment — each type of electromagnetic wave is associated with a spe-cial channel with a centralized management information system controlled in the background. Such de-sign can avoid EM-wave interference and encourage a delicate (or special) channel for energy transmit-ting. Hence, it can solve electrical devices charging problem or one may get the device charged anywhere and anytime. Furthermore, with a professional electronic circuit de- sign, together with meta-materials coated on the surface of a set antenna block, 90–100% of harvested renewable-clean energy might be transmitted. There is an alternative way of charging by using induc- tive coils; however, there are some defects in such case. Further advance is the introduction of electro- magnetic wormhole which can shield human beings from the influence of magnetic flux outside the tunnel during charging

Thermal Conductivity Analysis of Ethylene Glycol/H<sub>2</sub>O- Based MgFe<sub>2</sub>O<sub>4 </sub>Ferrofluid

The current investigation aims to synthesize MgFe2O4 magnetic nanoparticle and measure the thermal conductivity of MgFe2O4 ferrofluid. Prepared MgFe2O4 nanoparticle's structural characterization, the concentration of constituents, and surface morphology were analyzed using XRD, EDAX, and TEM respectively. This study also analyses the influence of magnetic flux on the thermal conductivity of MgFe2O4/ EG: H2O (60:40) based ferrofluids formed by the two-step method. Thermal conductivity of ferrofluid measured at different volume fractions (ranging from 0.01% to 0.20%) show that thermal conductivity augmented with an escalation in volume fraction and the highest enhancement of 10.32% was reached at 0.20% volume fraction. Results indicate that the applied magnetic flux improves the thermal conductivity of ferrofluid from 10.32% to 14.75% at 0.20% volume fraction and 350 Gauss Magnetic flux.

Induced current of high temperature superconducting loops by combination of exciting coil and thermal switch

With its commercialization, the second-generation (2G) high temperature superconducting (HTS) RE–Ba–Cu–O (REBCO, RE is rare earth) tape is extensively applied to the superconducting magnets in the high magnetic fields. However, unlike low temperature superconducting (LTS) magnets, the HTS magnet cannot operate in the persistent current mode (PCM) due to the immature superconducting soldering technique. In this paper, an exciting method for two HTS sub-loops, so-called charging and load loops, is proposed by flux pump consisting of exciting coil and controllable thermal switch. Two HTS sub-loops are made of an REBCO tape with two slits. An exciting coil with iron core is located in one sub-loop and is supplied with a triangular waveform current so that magnetic field is generated in another sub-loop. The influence of magnetic flux on induced current in load loop is presented and verified in experiment at 77 K. The relationship between the induced magnetic flux density and the current on the sub-loops having been calibrated, magnetic flux density, and induced current are obtained. The results show that the HTS sub-loops can be excited by a coil with thermal switch and the induced current increases with magnetic flux of exciting coil increasing, which is promising for persistent current operation mode of HTS magnets.

Effect of electrode separation in magnetron DC plasma sputtering on grain size of gold coated samples

In this work, an experimental research on a low voltage DC magnetron plasma sputtering (0-650) volt is used for coating gold on a glass substrate at a constant pressure of argon gas 0.2 mbar and deposition time of 30 seconds. We focused on the effects of operating conditions for the system such as, electrode separation and sputtering current on coated samples under the influence of magnetic flux. Electron temperature and electrons and ions densities are determined by a cylindrical single Langmuir probe. The results show the sensitivity of electrode separation lead to change the plasma parameters. Furthermore, the surface morphology of gold coated samples at different electrode separation and sputtering current were studied by atomic force microscopy (AFM). The AFM analysis showed that the variation of average grain diameter and average grain height is nonlinear with a minimum value of average grain diameter 90 nm at electrode separation of 4 cm and 30 mA sputtering current.

Dynamics of neurons in the pre-Bötzinger complex under magnetic flow effect

Breathing is a complex rhythmic movement. The dynamics of neuron firing activity has important implications in understanding the causes of pathological respiratory rhythm. Studies on electrophysiology have shown that the internal and external bioelectricity of nervous system may play important roles on firing activities of neuron. In this paper, the magnetic flow is added as a new variable to the Butera model to investigate the effect of electromagnetic induction on neuronal activities. The effect of magnetic flow on membrane potential is described by imposing additive memristive current on the membrane variable. The memristive current depends on the variation of magnetic flow. Direct and alternating currents of external stimulus are also added to the membrane potential. Dynamics of this modified model is discussed to consider the influence of magnetic flux on the membrane potential under different conditions of direct and alternating currents. The results show that the magnetic flux makes the pre-BotC neuron oscillate under a lower value of the direct current. Regular bursting and the mixed modes bursting types can be observed by changing the external condition and stimulus. Further studies on the combination effects of the parameter $${k_1}$$ and the direct and alternating currents are performed by two-parameter bifurcation analysis.

Electron transport through a linear tri-quantum-dot molecule Aharonov-Bohm interference

Using the non-equilibrium Keldysh Green's function technique, electron transport properties through a two-terminal linear tri-quantum-dot molecule Aharonov-Bohm (A-B) interference are investigated. The conductance as a function of electron energy is numerically calculated. The influence of magnetic flux and interdot coupling strength on the conductance is researched. Fano resonances emerge in the conductance spectrum, and two bound states in the continuum form simultaneously when the interdot couplings take appropriate values. A conductance dip is observed and evolves into an antiresonance band with increasing magnetic flux. The system can be designed as a quantum switch by adjusting the intramolecular couplings.

Quantum transport in coupled resonators enclosed synthetic magnetic flux

Quantum transport properties are instrumental to understanding quantum coherent transport processes. Potential applications of quantum transport are widespread, in areas ranging from quantum information science to quantum engineering, and not restricted to quantum state transfer, control and manipulation. Here, we study light transport in a ring array of coupled resonators enclosed synthetic magnetic flux. The ring configuration, with an arbitrary number of resonators embedded, forms a two-arm Aharonov–Bohm interferometer. The influence of magnetic flux on light transport is investigated. Tuning the magnetic flux can lead to resonant transmission, while half-integer magnetic flux quantum leads to completely destructive interference and transmission zeros in an interferometer with two equal arms.

Diagnosis of Rolling-Element Bearings Failure by Localized Electrical Current Between Track Surfaces of Races and Rolling-Elements

The diagnosis and cause analysis of rolling-element bearing failure have been well studied and established in literature. Failure of bearings due to unforeseen causes were reported as: puncturing of bearings insulation; grease deterioration; grease pipe contacting the motor base frame; unshielded instrumentation cable; the bearing operating under the influence of magnetic flux, etc. These causes lead to the passage of electric current through the bearings of motors and alternators and deteriorate them in due course. But, bearing failure due to localized electrical current between track surfaces of races and rolling-elements has not been hitherto diagnosed and analyzed. This paper reports the cause of generation of localized current in presence of shaft voltage. Also, it brings out the developed theoretical model to determine the value of localized current density depending on dimensional parameters, shaft voltage, contact resistance, frequency of rotation of shaft and rolling-elements of a bearing. Furthermore, failure caused by flow of localized current has been experimentally investigated.

YBCO SQUIDs fabricated by field-emission electron beam source

We report the applicability of YBa/sub 2/Cu/sub 3/O/sub 7-y/ (YBCO) SQUIDs fabricated by field-emission electron beam source. The junctions show hysteresis and self-resonance steps related to a high frequency resonance in the dc SQUID loop at a voltage V/sub res/=/spl Phi//sub 0//2/spl pi/(LC/2)/sup 1/2/ around 0.3 T/sub c/. The noise spectrum of the SQUIDs was measured with dc-bias schemes at different temperatures and showed values around 10/sup -4/ /spl Phi//sub 0//Hz/sup 1/2/ down to frequencies of 10 Hz at 40 K. The influence of magnetic flux, operating temperatures and flux-voltage transfer factor (|dV/d/spl Phi/|) were investigated. We also tested inverter operation of a dc-biased Josephson logic gate composed of an rf SQUID and a dc SQUID to realize logic circuit performance. Operation of the inverter has been successfully demonstrated although the operating temperature is low, around 10 K.

Noise properties of direct current SQUIDs with quasiplanar YBa2Cu3O7 Josephson junctions

We describe the noise performance of dc SQUIDs fabricated with quasiplanar ramp-type Josephson junctions on the basis of c-axis-oriented YBa2Cu3O7/PrBa2Cu3O7 thin-film heterostructures. The noise spectrum of the dc SQUIDs was measured with dc- and ac-bias schemes at different temperatures and showed values below 10−5 Φ0/Hz1/2 down to frequencies of about 1 Hz at 70 K. Up to now for the magnetic flux noise and the energy resolution obtained at 1 kHz and 77 K the best values were 2.5×10−6, Φ0/Hz1/2 and 3×10−31 J/Hz, respectively. A study of the white and 1/f noises of the SQUIDs was performed. The influence of magnetic flux, bias current, high static magnetic fields, and aging on the SQUID noise were investigated. The junctions and devices do not degrade due to aging in air or thermal cycling.

Josephson tunneling as a probe of the vortex-glass state

Josephson tunneling between superconducting electrodes in the vortex-glass state is considered. The Josephson coupling energy and phase offset are stochastic, the typical value of the former scaling as the Edwards-Anderson order parameter, Larkin-Ovchinikov length, and square root of the junction area. The influence of magnetic flux through the junction is explored, and magneto-fingerprints, reminiscent of universal conductance fluctuations, are predicted. Properties of SQUIDs are also examined, and it is concluded that Josephson phenomena may provide a useful probe of the vortex-glass state.