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A relation between the distance from the surface of a magnet and the number of cells required for a numerical calculation in order to secure the error below a certain threshold is derived. We also developed a method to obtain the ...
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A relation between the distance from the surface of a magnet and the number of cells required for a numerical calculation in order to secure the error below a certain threshold is derived. We also developed a method to obtain the magnetization at each part of the magnet from the experimentally measured magnetic field. This method is applied to three magnets with distinct patterns on magnetic-field-viewing film. Each magnet showed a unique pattern of magnetization. We found that the magnet that shows symmetric magnetization on the magnetic-field-viewing film is not uniformly magnetized. This method can be useful comparing the magnetization between magnets that yield typical magnetic field and those that yield atypical magnetic field.
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We analyze the dynamics of a charged particle moving in the presence of spatially modulated magnetic fields, motivated by recent transport experiments by Ye et al. (Phys. Rev. Lett. 74 (1995) 3013). We show from Poincare surfaces ...
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We analyze the dynamics of a charged particle moving in the presence of spatially modulated magnetic fields, motivated by recent transport experiments by Ye et al. (Phys. Rev. Lett. 74 (1995) 3013). We show from Poincare surfaces of section that the ratio of pinned orbits to chaotic orbits depends strongly on the energy and the structure parameters. We present a complete characterization of the dynamical behavior of such structures, and calculate the magnetoconductivity using a classical Kubo formula. We investigate the contribution to the conductivity from pinned and runaway orbits. Although the DC conductivity of the system depends strongly on the ratio of pinned to runaway trajectories, the high-frequency response reflects the topology of the different orbits. (C) 1998 Elsevier Science B.V. All rights reserved. [References: 6]
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Results of technological rotating magnetic field inductor rotation velocity investigation are presented. The analytical expression of rotation velocity in any point of active zone is obtained dependently on any phase magnetic flux...
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Results of technological rotating magnetic field inductor rotation velocity investigation are presented. The analytical expression of rotation velocity in any point of active zone is obtained dependently on any phase magnetic flux density vectors amplitudes and directions. The mean rotation velocity throughout the one period is equal to the angular velocity of excitation current. The dependences of maximal instant rotation velocity deviation at mean value on non-equality of different phases magnetic flux density vectors values and directions are obtained.
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Приведены результаты экспериментальных исследований размагничивающего и поверхностного эффектов в протяженных ферромагни...
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Приведены результаты экспериментальных исследований размагничивающего и поверхностного эффектов в протяженных ферромагнитных стержнях, намагничиваемых переменным магнитным полем катушек разной длины в диапазоне частот 20 Гц - 50 кГц. Дано физически обоснованное объяснение независимости составляющих комплексной магнитной проницаемости от длины катушек на повышенных частотах этого диапазона.
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The results of experimental researches of demagnetizing and skin effects in extended ferromagnetic rods, magnetized by alternative magnetic field of coils of arbitrary lengths, are obtained. Physically justified explanation of com...
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The results of experimental researches of demagnetizing and skin effects in extended ferromagnetic rods, magnetized by alternative magnetic field of coils of arbitrary lengths, are obtained. Physically justified explanation of complex magnetic permeability components independence from coils lengths on high frequencies is presented.
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A non-planar two-dimensional electron gas (2DEG) has been realised by using molecular beam epitaxy to grow a high mobility heterostructure on a (1 0 0) n(+)-GaAs layer selectively etched to create a two-dimensional array of caviti...
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A non-planar two-dimensional electron gas (2DEG) has been realised by using molecular beam epitaxy to grow a high mobility heterostructure on a (1 0 0) n(+)-GaAs layer selectively etched to create a two-dimensional array of cavities through the n(+)-GaAs which are bounded by higher-index facets. Far-infrared (FIR) cyclotron resonance spectra show one absorption mode associated with an electron gas formed inside the cavities and confined in both lateral directions. Typical confinement energies of 23 cm(-1) and widths of 1000 nm are derived from the FIR spectra and magneto resistance measurements. A second mode occurs at a frequency lower than that measured for a planar 2DEG. Its origin is discussed in terms of magneto-plasmons excited across a non-planar region of the electron gas in a spatially non-uniform magnetic held. Combining this information with atomic force microscopy images provides a comprehensive picture of the nature of the lateral confinement in this structure. (C) 1998 Elsevier Science B.V. All rights reserved. [References: 9]
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In this paper, local magnetic measurements are carried out in magnetic circuits with non-uniform electromagnetic field patterns, including excitation windings and/or air gaps, as in the case of rotating electrical machines. The ef...
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In this paper, local magnetic measurements are carried out in magnetic circuits with non-uniform electromagnetic field patterns, including excitation windings and/or air gaps, as in the case of rotating electrical machines. The effects of sensor choice, sensor noise sensitivity and electromagnetic field inhomogeneity on the accuracy of the identification of the magnetic material properties are investigated. Moreover, the validity of the local magnetic measurements is confirmed by numerical models, based on the finite element method. The paper comprehensively discusses the possibilities, difficulties and limitations of local magnetic measurements in magnetic circuits with non-uniform electromagnetic fields. It is shown that higher accuracy is obtained when the measurements are performed in regions with less stray fields.
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In the work, a charged particle under influence of non-uniform external magnetic field has been considered. First, the Schroedinger equation is solved by emplying the Nikiforov-Uvarov (NU) method and derived analytically the energ...
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In the work, a charged particle under influence of non-uniform external magnetic field has been considered. First, the Schroedinger equation is solved by emplying the Nikiforov-Uvarov (NU) method and derived analytically the energy states and wave functions. Then, we have studied magnetic susceptibility, heat capacity, electronic and optical properties of the system. It is found that energy levels, optical properties, heat capacity and magnetic susceptibility depend strongly on the effect of non-uniform magnetic field. With changing the non-uniform magnetic field, the system can be shown diamagnetic or paramagnetic behavior. The heat capacity displays the peak structure under effect of non-uniform magnetic field. The refractive index change and absorption coefficient increase and their peaks shift toward higher energies under non-uniform magnetic field.
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The magnetic abrasive finishing process of thin sleeve of Al alloy with different diameter is studied based on self-adaptive characteristics. Some technical innovations are done such as fixing smooth magnetic mandrel or slot magne...
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The magnetic abrasive finishing process of thin sleeve of Al alloy with different diameter is studied based on self-adaptive characteristics. Some technical innovations are done such as fixing smooth magnetic mandrel or slot magnetic mandrel and so on in the workpiece interior for improving the structure style of the working space and characteristic of magnetic field. Experiments on thin sleeve of Al alloy are done and their finishing effects are contrasted. Research results indicate that fixing slot magnetic spindle in the workpiece interior can increase efficiency and improve quality for large thin non-magnetic sleeve.
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Perturbation theory has been applied to evaluate the induced electronic moments and magnetic field at the nuclei of an SFg molecule interacting with an external magnetic field with a spatially uniform gradient. Contributions to ma...
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Perturbation theory has been applied to evaluate the induced electronic moments and magnetic field at the nuclei of an SFg molecule interacting with an external magnetic field with a spatially uniform gradient. Contributions to magnetic susceptibility and magnetic shielding of the nuclei have been evaluated using the random phase approximation within the framework of accurate Hartree-Fock zero order wavefuctions. The quality of the calculations has been judged by the fulfillment of sum rules for the origin dependence of the response properties.
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