Fabrication of c-axis oriented polycrystalline ZnO by using a rotating magnetic field and following sintering

2006 ◽  
Vol 21 (3) ◽  
pp. 703-707 ◽  
Author(s):  
Satoshi Tanaka ◽  
Atsushi Makiya ◽  
Zenji Kato ◽  
Nozomu Uchida ◽  
Tsunehisa Kimura ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Crystal Form ◽  
Rotating Magnetic Field ◽  
Field Control ◽  
Degree Of Orientation ◽  
Oriented Polycrystalline ◽  
The Magnetic Field ◽  
Zno Ceramics ◽  
Functional Ceramics

We succeeded in fabricating c-axis (00l) oriented ZnO ceramics by using a rotating magnetic field and a subsequent sintering treatment. The degree of orientation in the green compact was about 0.5 along (00l) on the Lotgering scale. The degree of orientation increased to 0.99 after sintering at 1573 K. Particles can also be oriented in a static magnetic field, but along the direction of the a-axis or a,b-axes (h00), (hk0). These results show that selected axes can be oriented by controlling the magnetic field. Control of the crystal form in microstructures is expected to result in improvements in and better miniaturization of functional ceramics.

scholarly journals Orientation of erythrocytes in a strong static magnetic field

Blood ◽  
1993 ◽  
Vol 82 (4) ◽  
pp. 1328-1334 ◽  
Author(s):  
T Higashi ◽  
A Yamagishi ◽  
T Takeuchi ◽  
N Kawaguchi ◽  
S Sagawa ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Magnetic Levitation ◽  
Diagnostic Technique ◽  
The Body ◽  
Transport Systems ◽  
Magnetic Field Direction ◽  
Disk Plane ◽  
Degree Of Orientation ◽  
The Magnetic Field

Abstract The frequency of exposure to strong magnetic fields has increased as the magnetic-resonance image-diagnostic technique (MRI) and passenger transport systems based on the principle of magnetic levitation have come into wider use. Accordingly, it has become necessary to more systematically assess their influence on the body and set strict guidelines on acceptable limits of magnetism exposure. Therefore, we have assessed the influence of an uniform static magnetic field (8 T in maximum) on normal erythrocytes. The erythrocytes were oriented with their disk plane parallel to the magnetic field direction. These erythrocytes were influenced even by 1 T and almost 100% of them were oriented when exposed to 4 T. Furthermore, the degree of orientation was not influenced by the state of hemoglobin (oxy: diamagnetic, deoxy and met: paramagnetic). The dependence of the measured degree of orientation on the intensity of the magnetic field was in good agreement with the theoretical equation for the magnetic orientation of diamagnetic substances. As a result of a numerical analysis based on the equation, the anisotropic diamagnetic susceptibility of erythrocytes was found to be delta chi = 8 x 10(-22) electromagnetic units/erythrocyte. It was almost in agreement with the calculated value delta chi = 6 x 10(-22) emu/erythrocyte estimated from the diamagnetism of the membrane constituents of erythrocyte.

scholarly journals Orientation of erythrocytes in a strong static magnetic field

Blood ◽  
1993 ◽  
Vol 82 (4) ◽  
pp. 1328-1334 ◽  
Author(s):  
T Higashi ◽  
A Yamagishi ◽  
T Takeuchi ◽  
N Kawaguchi ◽  
S Sagawa ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Magnetic Levitation ◽  
Diagnostic Technique ◽  
The Body ◽  
Transport Systems ◽  
Magnetic Field Direction ◽  
Disk Plane ◽  
Degree Of Orientation ◽  
The Magnetic Field

The frequency of exposure to strong magnetic fields has increased as the magnetic-resonance image-diagnostic technique (MRI) and passenger transport systems based on the principle of magnetic levitation have come into wider use. Accordingly, it has become necessary to more systematically assess their influence on the body and set strict guidelines on acceptable limits of magnetism exposure. Therefore, we have assessed the influence of an uniform static magnetic field (8 T in maximum) on normal erythrocytes. The erythrocytes were oriented with their disk plane parallel to the magnetic field direction. These erythrocytes were influenced even by 1 T and almost 100% of them were oriented when exposed to 4 T. Furthermore, the degree of orientation was not influenced by the state of hemoglobin (oxy: diamagnetic, deoxy and met: paramagnetic). The dependence of the measured degree of orientation on the intensity of the magnetic field was in good agreement with the theoretical equation for the magnetic orientation of diamagnetic substances. As a result of a numerical analysis based on the equation, the anisotropic diamagnetic susceptibility of erythrocytes was found to be delta chi = 8 x 10(-22) electromagnetic units/erythrocyte. It was almost in agreement with the calculated value delta chi = 6 x 10(-22) emu/erythrocyte estimated from the diamagnetism of the membrane constituents of erythrocyte.

scholarly journals The orientation of iron–sulphur clusters in membrane multilayers prepared from aerobically-grown Escherichia coli K12 and a cytochrome-deficient mutant

1980 ◽  
Vol 190 (2) ◽  
pp. 385-393 ◽  
Author(s):  
Haywood Blum ◽  
Robert K. Poole ◽  
Tomoko Ohnishi
Keyword(s):  
Magnetic Field ◽  
Escherichia Coli ◽  
Cytoplasmic Membrane ◽  
Deficient Mutant ◽  
E Coli ◽  
Membrane Particles ◽  
Degree Of Orientation ◽  
High Degree ◽  
Cytochrome Content ◽  
The Magnetic Field

1. Membrane particles prepared from ultrasonically-disrupted, aerobically-grown Escherichia coli were centrifuged on to a plastic film that was supported perpendicular to the centrifugal field to yield oriented membrane multilayers. In such preparations, there is a high degree of orientation of the planes of the membranes such that they lie parallel to each other and to the supporting film. 2. When dithionite- or succinate-reduced multilayers are rotated in the magnetic field of an e.p.r. spectrometer, about an axis lying in the membrane plane, angular-dependent signals from an iron–sulphur cluster at gx=1.92, gy=1.93 and gz=2.02 are seen. The g=1.93 signal has maximal amplitude when the plane of the multilayer is perpendicular to the magnetic field. Conversely, the g=2.02 signal is maximal when the plane of the multilayer is parallel with the magnetic field. 3. Computer simulations of the experimental data show that the cluster lies in the cytoplasmic membrane with the gy axis perpendicular to the membrane plane and with the gx and gz axes lying in the membrane plane. 4. In partially-oxidized multilayers, a signal resembling the mitochondrial high-potential iron–sulphur protein (Hipip) is seen whose gz=2.02 axis may be deduced as lying perpendicular to the membrane plane. 5. Appropriate choice of sample temperature and receiver gain reveals two further signals in partially-reduced multilayers: a g=2.09 signal arises from a cluster with its gz axis in the membrane plane, whereas a g=2.04 signal is from a cluster with the gz axis lying along the membrane normal. 6. Membrane particles from a glucose-grown, haem-deficient mutant contain dramatically-lowered levels of cytochromes and exhibit, in addition to the iron–sulphur clusters seen in the parental strain, a major signal at g=1.90. 7. Only the latter may be demonstrated to be oriented in multilayer preparations from the mutant. 8. Comparisons are drawn between the orientations of the iron–sulphur proteins in the cytoplasmic membrane of E. coli and those in mitochondrial membranes. The effects of diminished cytochrome content on the properties of the iron–sulphur proteins are discussed.

Swirling Flow of Magnetic Fluid in Multi-Pole Rotating Magnetic Field

2003 ◽  
Author(s):  
Kenichi Kamioka ◽  
Ryuichiro Yamane
Keyword(s):  
Magnetic Field ◽  
Fluid Flow ◽  
Circular Cylinder ◽  
Phase Velocity ◽  
Magnetic Fluid ◽  
Swirling Flow ◽  
Peak Velocity ◽  
Rotating Magnetic Field ◽  
Outer Periphery ◽  
The Magnetic Field

The experiments are conducted on the magnetic fluid flow induced by the multi-pole rotating magnetic field in a circular cylinder. The numbers of poles are two, four, six, eight and twelve. The applied electric current and frequency are 2∼6 A and 20∼60 Hz, respectively. The peak velocity of the flow increases with the increase in the strength and the phase velocity of the magnetic field. As the increase in the number of poles, the flow shifts to the outer periphery.

scholarly journals Investigation of mixing time in liquid under influence of rotating magnetic field

2017 ◽  
Vol 38 (4) ◽  
pp. 555-565
Author(s):  
Alicja Przybył ◽  
Rafał Rakoczy ◽  
Maciej Konopacki ◽  
Marian Kordas ◽  
Radosław Drozd ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Experimental Investigation ◽  
Reynolds Number ◽  
Mixing Time ◽  
Rotating Magnetic Field ◽  
Homogenization Time ◽  
Set Up ◽  
The Relationship ◽  
The Magnetic Field

Abstract The aim of the study was to present an experimental investigation of the influence of the RMF on mixing time. The obtained results suggest that the homogenization time for the tested experimental set-up depending on the frequency of the RMF can be worked out by means of the relationship between the dimensionless mixing time number and the Reynolds number. It was shown that the magnetic field can be applied successfully to mixing liquids.

Effect of Processing Variables on The Magnetic Field Orientation of Liquid Crystalline Thermosets

1999 ◽  
Vol 559 ◽  
Author(s):  
Derek M. Lincoln ◽  
Elliot P. Douglas
Keyword(s):  
Magnetic Field ◽  
Liquid Crystalline ◽  
Fractional Factorial Design ◽  
Fractional Factorial ◽  
Field Orientation ◽  
Magnetic Field Orientation ◽  
Liquid Crystalline Epoxy ◽  
Processing Variables ◽  
Degree Of Orientation ◽  
The Magnetic Field

ABSTRACTWe have investigated the effect of various processing variables on the magnetic field orientation of a liquid crystalline epoxy. By using a modified fractional factorial design, we created an empirical model which can be used to predict the degree of orientation as a function of these variables. The model predicts the correct qualitative trends, namely that orientation increases with increasing magnetic field strength, increases with increasing time in the field, and decreases with increasing B-staging. The model also reveals some surprising effects of B-staging on the degree of orientation.

Spin reorientation transition: phase diagrams and entropy change

2011 ◽  
Vol 1310 ◽  
Author(s):  
Vittorio Basso ◽  
Carlo P. Sasso ◽  
Michaela Kuepferling
Keyword(s):  
Magnetic Field ◽  
Easy Axis ◽  
Entropy Change ◽  
Rotating Magnetic Field ◽  
Spin Reorientation ◽  
Temperature Dependent ◽  
First Order ◽  
Crystalline Anisotropy ◽  
The Magnetic Field ◽  
Magneto Crystalline Anisotropy

ABSTRACTIn this paper we review the phase diagram and derive the entropy change for spin reorientation transitions by considering first order magnetization process theory with temperature dependent magneto-crystalline anisotropy constants. We derive the magnetic field-induced entropy change Δs for a transition between easy axis and easy plane, showing that for alternating magnetic field, Δs has a change of sign at the reorientation temperature, while for rotating magnetic field its sign is definite. We apply the model to CoZn W-type barium ferrite.

Effect of a static magnetic field on the preparation of MnOOH and Mn3O4 by a hydrothermal process

RSC Advances ◽  
2016 ◽  
Vol 6 (25) ◽  
pp. 21037-21042 ◽  
Author(s):  
L. C. Dong ◽  
Y. B. Zhong ◽  
S. Zhe ◽  
T. Y. Zheng ◽  
H. Wang
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Static Magnetic Field ◽  
Hydrothermal Process ◽  
Single Crystalline ◽  
20 Nm ◽  
The Magnetic Field

In this paper, the shape of the samples was changed by the magnetic field. Single-crystalline nanowires (20 nm in diameter and 1 μm in length) of MnOOH were obtained under zero magnetic fields. However, cubic particles of Mn3O4 were formed when a magnetic field was applied.

Waves in a cold plasma with spatially periodic sheared fields

1989 ◽  
Vol 42 (1) ◽  
pp. 153-164 ◽  
Author(s):  
D. A. Diver ◽  
E. W. Laing ◽  
C. C. Sellar
Keyword(s):  
Magnetic Field ◽  
Wave Propagation ◽  
Cold Plasma ◽  
Density Fluctuations ◽  
Rotating Magnetic Field ◽  
Physical Parameters ◽  
Order Ordinary Differential Equation ◽  
Spatially Periodic ◽  
Constant Magnitude ◽  
The Magnetic Field

We have studied wave propagation in a cold plasma, in the presence of a spatially rotating magnetic field of constant magnitude. New features introduced by this variation include streaming velocities and a plasma current in equilibrium and density fluctuations. We present only the case of wave propagation along the axis of rotation of the magnetic field. A set of ordinary differential equations for the electric field components is obtained, which may be combined into a single fourth-order ordinary differential equation with periodic coefficients. Solutions are obtained in closed form and their nature is determined in terms of the physical parameters of the System, magnetic field strength, number density and wave frequency.

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