The impact on the magnetic field growth of half-metallic Fe3O4 thin films

The work purpose is the investigation of magnetic field impact upon properties of friction steel surfaces at fit stripping with tightness through manifested effects and their wear visually observed. On the spots of a real contact the magnetic field increases active centers, their amount and saturation with the time of dislocation outlet, and has an influence upon tribo-mating. The external electro-magnetic field promotes the increase of the number of active centers at the expense of dislocations outlet on the contact surface, and the increase of a physical contact area results in friction tie strengthening and growth of a friction factor. By the example of friction pairs of a spentonly unit in the suspension of coach cars there is given a substantiation of actuality and possibility for the creation of technical devices with the controlled factor of friction and the stability of effects achieved is also confirmed experimentally. Investigation methods: the fulfillment of laboratory physical experiments on the laboratory plant developed and patented on bush-rod samples inserted with the fit and tightness. The results of investigations and novelty: the impact of the magnetic field upon the value of a stripping force of a press fit with the guaranteed tightness is defined. Conclusion: there is a possibility to control a friction factor through the magnetic field impact upon a friction contact.

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Qualitative and quantitative assessment of magnetic vestibular stimulation in humans

Journal of Vestibular Research ◽

10.3233/ves-201538 ◽

2020 ◽

Vol 30 (6) ◽

pp. 353-361

Author(s):

Rebecca S. Dewey ◽

Rachel Gomez ◽

Chris Degg ◽

David M. Baguley ◽

Paul M. Glover

Keyword(s):

Magnetic Field ◽

Objective Measure ◽

Quantitative Measure ◽

Vestibular Stimulation ◽

Initial Study ◽

Clinical Test ◽

Healthy Control ◽

Student’S T ◽

The Impact ◽

The Magnetic Field

The sensation of phantom motion or exhibition of bodily sway is often reported in the proximity of an MR scanner. It is proposed that the magnetic field stimulates the vestibular system. There are a number of possible mechanisms responsible, and the relative contributions of susceptibility on the otolithic receptors and the Lorentz force on the cupulae have not yet been explored. This exploratory study aims to investigate the impact of being in the proximity of a 7.0 T MR scanner. The modified clinical test of sensory interaction on balance (mCTSIB) was used to qualitatively ascertain whether or not healthy control subjects who passed the mCTSIB in normal conditions 1) experienced subjective sensations of dizziness, vertigo or of leaning or shifting in gravity when in the magnetic field and 2) exhibited visibly increased bodily sway whilst in the magnetic field compared to outside the magnetic field. Condition IV of the mCTSIB was video recorded outside and inside the magnetic field, providing a semi-quantitative measure of sway. For condition IV of the mCTSIB (visual and proprioceptive cues compromised), all seven locations/orientations around the scanner yielded significantly more sway than at baseline (p < 0.01 FDR). A Student’s t-test comparing the RMS velocity of a motion marker on the upper arm during mCTSIB condition IV showed a significant increase in the amount of motion exhibited in the field (T = 2.59; d.f. = 9; p = 0.029) compared to outside the field. This initial study using qualitative measures of sway demonstrates that there is evidence for MR-naïve individuals exhibiting greater sway while performing the mCTSIB in the magnetic field compared to outside the field. Directional polarity of sway was not significant. Future studies of vestibular stimulation by magnetic fields would benefit from the development of a sensitive, objective measure of balance function, which can be performed inside a magnetic field.

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Magnetism of CoFe2O4 thin films annealed under the magnetic field

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2015.06.089 ◽

2015 ◽

Vol 394 ◽

pp. 287-291 ◽

Cited By ~ 10

Author(s):

Y.Q. Dai ◽

J.M. Dai ◽

X.W. Tang ◽

Z.F. Zi ◽

K.J. Zhang ◽

...

Keyword(s):

Magnetic Field ◽

Thin Films ◽

The Magnetic Field

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Uticaj armirano betonskog stuba na raspodelu magnetskog polja mešovitog voda

Energija, Ekonomija, Ekologija ◽

10.46793/eee20-1-2.058g ◽

2020 ◽

Vol 22 (1-2) ◽

pp. 58-64

Author(s):

Teodora Gavrilov ◽

◽

Karolina Kasaš-Lažetić ◽

Kristian Haška ◽

Miroslav Prša

Keyword(s):

Magnetic Field ◽

Field Distribution ◽

Magnetic Field Distribution ◽

Magnetic Flux Density ◽

Reinforcing Bars ◽

Magnitude Distribution ◽

Calculation Results ◽

Mixed Power ◽

The Impact ◽

The Magnetic Field

In this paper, the analysis of magnetic field distribution of overhead mixed power line (20 kV/0.4 kV) supported by reinforced concrete towers, named MNL-12 is presented. The impact of ferromagnetic, conductive parts of the pylons (reinforcing bars, billets and cross arm beams) on magnetic field distribution is investigated. The numerical calculations were performed in COMSOL Multiphysics program package on simplified 2D model. The main goal of the calculations was to examine the impact of currents induced in ferromagnetic conductive parts on magnetic field produced by currents in the power system’s conductors. The calculation results are presented graphically, as the diagrams of the magnetic flux density magnitude distribution in the tower plan, normal to the system’s axe. The calculation results demonstrated that the magnetic field of induced currents decreases the magnetic field produced by the currents of overhead power system.

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Abstract 14497: Mri Effects on Pacemaker/ICD Within the Magnetic Field; An Intra-observer Variability Study

Circulation ◽

10.1161/circ.142.suppl_3.14497 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Robert W Biederman ◽

Loretta Gevenosky ◽

Geetha Rayarao ◽

RONALD WILLIAMS ◽

Richard Lombardi ◽

...

Keyword(s):

Magnetic Field ◽

High Field ◽

Meaningful Use ◽

Observer Variability ◽

Intrinsic Variability ◽

Mri Scan ◽

Clinical Routine ◽

The Impact ◽

Variability Study ◽

The Magnetic Field

Introduction: The evolution of pacemaker/ICD safety in the magnetic field has triggered considerable interest in more clinical routine use. However, many limitations to widespread adoption of this seemingly implausible idea just a few years ago remain: unresolved impact of the high magnetic field, RF amplitude and oscillatory forces on electronics with possible high field damage to capacitor, solenoid and microcircuitry. However, given recent vender refinements over the last 10 years, we hypothesized that the impact on such circuitry may be far less than expected. Method: Consecutive interrogation of 940 pts who underwent clinically indicated MRI were evaluated over 5 years. This cohort was comprised of neuro/neurosurgical (72%), orthopedic (11%) and cardiac (17%) cases. Routine interrogation was performed within 10 min of entry into the bore of a dedicated Cardiac MRI (GE, 1.5T, WI). As well, reinterrogation was performed within 10 min of departure MRI (average 21±12min). At the time of interrogation pre and post MRI, a separate, repeat interrogation was performed within 5 min of each other such that 2 sets of PM/ICD parameters were obtained pre and post MRI. Result: No complications to either pt or device occurred during the MRI comprising 564 PMs and 376 ICDs. A cardiologist was present guiding the interrogation, configuration, and reconfiguration of the PM/ICD as well was present for entire MRI. There were no significant differences in common clinical parameters. More importantly, there was no difference in any parameter when compared in any order pre to post MRI scan. See Table. Conclusion: Intrinsic variability and inherent changes triggered by MRI environments are clinically insignificant and statistically negligible thereby removing yet another of the last remaining fears and apprehensions for primary PM/ICD failure and destruction as we move towards a more uniform acceptance of this technology for clinically meaningful use, dissemination and acceptance.

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The Impact of Sinusoidal Surface Temperature on the Natural Convective Flow of a Ferrofluid along a Vertical Plate

Mathematics ◽

10.3390/math7111014 ◽

2019 ◽

Vol 7 (11) ◽

pp. 1014 ◽

Cited By ~ 7

Author(s):

Essam R. EL-Zahar ◽

Ahmed M. Rashad ◽

Laila F. Seddek

Keyword(s):

Magnetic Field ◽

Nusselt Number ◽

Surface Temperature ◽

Drag Coefficient ◽

Volume Fraction ◽

Differential Quadrature Method ◽

Grid Points ◽

The Impact ◽

Sinusoidal Surface ◽

The Magnetic Field

The spotlight of this investigation is primarily the effectiveness of the magnetic field on the natural convective for a Fe3O4 ferrofluid flow over a vertical radiate plate using streamwise sinusoidal variation in surface temperature. The energy equation is reduplicated by interpolating the non-linear radiation effectiveness. The original equations describing the ferrofluid motion and energy are converted into non-dimensional equations and solved numerically using a new hybrid linearization-differential quadrature method (HLDQM). HLDQM is a high order semi-analytical numerical method that results in analytical solutions in η -direction, and so the solutions are valid overall in the η domain, not only at grid points. The dimensionless velocity and temperature curves are elaborated. Furthermore, the engineering curiosity of the drag coefficient and local Nusselt number are debated and sketched in view of various emerging parameters. The analyzed numerical results display that applying the magnetic field to the ferroliquid generates a dragging force that diminishes the ferrofluid velocity, whereas it is found to boost the temperature curves. Furthermore, the drag coefficient sufficiently minifies, while an evolution in the heat transfer rate occurs as nanoparticle volume fraction builds. Additionally, the augmentation in temperature ratio parameter signifies a considerable growth in the drag coefficient and Nusselt number. The current theoretical investigation may be beneficial in manufacturing processes, development of transport of energy, and heat resources.

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Precision Analysis and Design of Rotating Coil Magnetic Measurements System

Applied Sciences ◽

10.3390/app10238454 ◽

2020 ◽

Vol 10 (23) ◽

pp. 8454

Author(s):

Soontorn Odngam ◽

Chaiyut Preecha ◽

Prapaiwan Sanwong ◽

Woramet Thongtan ◽

Jiraphon Srisertpol

Keyword(s):

Magnetic Field ◽

Control System ◽

Magnetic Measurements ◽

Speed Control ◽

Measuring Instruments ◽

Dipole Magnet ◽

Analysis And Design ◽

Speed Control System ◽

The Impact ◽

The Magnetic Field

This research presents the design and construction of measuring instruments for a dipole magnetic field using a rotating coil technique. This technique is a closed-loop speed-control system where a Proportional-Integral (PI) controller works together with the intensity measurement of the magnetic field through the rotating coil. It was used to analyze the impact on the accuracy of the electromagnetic at speed ranges of 60, 90, and 120 rpm. The error estimation in the measurement of the normal dipole and skew dipole magnet caused by the steady-state error of the speed control system and the rotational search coil in whirling motion are demonstrated. Rotating unbalance, shaft coupling, and misalignment from its setup disturbed the performance of the speed control system as a nonlinear system.

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Considerations on the Magnetic Field Problem in Superconducting Thin Films

Broken Symmetry - World Scientific Series in 20th Century Physics ◽

10.1142/9789812795823_0016 ◽

1995 ◽

pp. 173-186

Author(s):

YOICHIRO NAMBU ◽

SAN FU TUAN

Keyword(s):

Magnetic Field ◽

Thin Films ◽

Superconducting Thin Films ◽

Field Problem ◽

The Magnetic Field

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The interphase surface energy in some pure and impure superconductors

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1960.0075 ◽

1960 ◽

Vol 255 (1282) ◽

pp. 407-426 ◽

Cited By ~ 30

Keyword(s):

Magnetic Field ◽

Thin Films ◽

Surface Energy ◽

Detailed Analysis ◽

Energy Parameter ◽

Transverse Magnetic ◽

Superconducting Phase ◽

Interphase Surface ◽

Dilute Alloys ◽

The Magnetic Field

A new method has been developed for obtaining relative values of the surface energy parameter, Δ, in superconductors. It involves the measurement of the resistance of thin films subjected to a transverse magnetic field. The method has been applied to tin, indium and aluminium and to dilute alloys of the first two. The principal new results are that Δ is 1⋅48 times larger in indium than in tin and that the addition of impurity to either metal lowers Δ without changing the nature of its temperature dependence. These conclusions are compared with current theories of the interphase surface energy. An attempt has been made to deduce the absolute magnitude of Δ, which requires a detailed analysis of the way in which the last traces of the superconducting phase are eliminated from the film by the action of the magnetic field. The analysis is necessarily over-simplified but it does give a figure for Δ in pure tin which is reasonably consistent with the previous estimates of Faber and Sharvin.

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