Two-Dimensional Patterns of Magnetic Particles at Air−Water or Glass−Water Interfaces Induced by an External Magnetic Field:  Theory and Simulation of the Formation Process

We consider a noncommutative description of graphene. This description consists of a Dirac equation for massless Dirac fermions plus noncommutative corrections, which are treated in the presence of an external magnetic field. We argue that, being a two-dimensional Dirac system, graphene is particularly interesting to test noncommutativity. We find that momentum noncommutativity affects the energy levels of graphene and we obtain a bound for the momentum noncommutative parameter.

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Flow Visualization by Means of Contactless Inductive Flow Tomography in the Presence of a Magnetic Brake

Journal for Manufacturing Science and Production ◽

10.1515/jmsp-2014-0037 ◽

2015 ◽

Vol 15 (1) ◽

pp. 41-48 ◽

Cited By ~ 1

Author(s):

Matthias Ratajczak ◽

Thomas Wondrak ◽

Klaus Timmel ◽

Frank Stefani ◽

Sven Eckert

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

Magnetic Fields ◽

Flow Field ◽

Continuous Casting ◽

Flow Structure ◽

Cross Section ◽

Two Dimensional ◽

Slab Casting ◽

Two Dimensional Flow

AbstractIn continuous casting DC magnetic fields perpendicular to the wide faces of the mold are used to control the flow in the mold. Especially in this case, even a rough knowledge of the flow structure in the mold would be highly desirable. The contactless inductive flow tomography (CIFT) allows to reconstruct the dominating two-dimensional flow structure in a slab casting mold by applying one external magnetic field and by measuring the flow-induced magnetic fields outside the mold. For a physical model of a mold with a cross section of 140 mm×35 mm we present preliminary measurements of the flow field in the mold in the presence of a magnetic brake. In addition, we show first reconstructions of the flow field in a mold with the cross section of 400 mm×100 mm demonstrating the upward scalability of CIFT.

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A NONPERTURBATIVE CALCULATION FOR THE EFFECTIVE POTENTIAL OF THE $\left(\frac{g}{4}\phi^{4}-J\phi\right)_{1+1}$ SCALAR FIELD THEORY USING THE OSCILLATOR REPRESENTATION METHOD WITH BOREL RESUMMATION

International Journal of Modern Physics A ◽

10.1142/s0217751x07034374 ◽

2007 ◽

Vol 22 (06) ◽

pp. 1265-1278

Author(s):

ABOUZEID M. SHALABY ◽

S. T. EL-BASYOUNY

Keyword(s):

Magnetic Field ◽

Field Theory ◽

Phase Transition ◽

Scalar Field ◽

External Magnetic Field ◽

Effective Potential ◽

Oscillator Representation ◽

Constructive Field Theory ◽

Representation Method ◽

Oscillator Representation Method

We established a resummed formula for the effective potential of [Formula: see text] scalar field theory that can mimic the true effective potential not only at the critical region but also at any point in the coupling space. We first extend the effective potential from the oscillator representation method, perturbatively, up to g3 order. We supplement perturbations by the use of a resummation algorithm, originally due to Kleinert, Thoms and Janke, which has the privilege of using the strong coupling as well as the large coupling behaviors rather than the conventional resummation techniques which use only the large order behavior. Accordingly, although the perturbation series available is up to g3 order, we found a good agreement between our resummed effective potential and the well-known features from constructive field theory. The resummed effective potential agrees well with the constructive field theory results concerning existing and order of phase transition in the absence of an external magnetic field. In the presence of the external magnetic field, as in magnetic systems, the effective potential shows nonexistence of phase transition and gives the behavior of the vacuum condensate as a monotonic increasing function of J, in complete agreement with constructive field theory methods.

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Study of the Performance of Practical Magneto-Rheological Elastomers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.430-432.1979 ◽

2012 ◽

Vol 430-432 ◽

pp. 1979-1983

Author(s):

Wei Bang Feng ◽

Xue Yang ◽

Zhi Qiang Lv

Keyword(s):

Magnetic Field ◽

Mechanical Properties ◽

Mechanical Property ◽

Magnetic Properties ◽

External Magnetic Field ◽

Magnetic Particles ◽

Poor Performance ◽

Electrical And Magnetic Properties ◽

Intelligent Material ◽

Magneto Rheological

Magneto-rheological elastomer( MR elastomer) is an emerging intelligent material made up of macromolecule polymer and magnetic particles. While a promising wide application it has in the fields of warships vibration controlling for its controllable mechanical, electrical and magnetic properties by external magnetic field, design and application of devices based on it are facing great limitations imposed by its poor performance in mechanical properties and magneto effect. Aiming at developing a practical MR elastomer, a new confecting method was proposed in this paper. Then, following this new method and using a specificly designed solidifying matrix, an amido- polyester MR elastomer was developed with its mechanical property systemically explored.

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Thermodynamics of Bidisperse Ferrofluids in Zero External Magnetic Field: Theory and Simulations

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.233-234.331 ◽

2015 ◽

Vol 233-234 ◽

pp. 331-334

Author(s):

Anna Yu. Solovyova ◽

Ekaterina A. Elfimova

Keyword(s):

Magnetic Field ◽

Field Theory ◽

Free Energy ◽

External Magnetic Field ◽

Volume Concentration ◽

Helmholtz Free Energy ◽

Hard Spheres ◽

Particle Volume ◽

Simulation Data ◽

Theoretical Predictions

The thermodynamic properties of a ferrofluid modeled by a bidisperse system of dipolar hard spheres in the absence of external magnetic field are investigated using theory and simulations. The theory is based on the virial expansion of the Helmholtz free energy in terms of particle volume concentration. Comparison between the theoretical predictions and simulation data shows a great agreement of the results.

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