Alignment of HAp Crystal Using a Sample Rotation in a Static Magnetic Field

Formation of crystallographically orientaed hydroxyapatite (HAp) is one of the promising ways to utilize their anisotropic nature of chemical and biological properties. On the other hand, the development of super conducting magnet technology enables to introduce a high magnetic field which can control crystal orientation of non-magnetic materials with magnetic anisotropy. In this study, a high magnetic field and sample rotation are simultaneously imposed on the hydroxyapatite during a slip casting process in order to align its c-plane within a horizontal plane. From X-ray diffraction, it has been found that the HAp crystals in the sample treated with the magnetic field and the sample rotation were oriented to a particular direction in the slip casting process and it was enhanced by the subsequent sintering process, while the c-axis crystal orientation of the sample treated without the magnetic field and with the sample rotation was not observed before and after the sintering.

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Structure Control of Hydroxyapatite Using a Magnetic Field

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.1565 ◽

2007 ◽

Vol 561-565 ◽

pp. 1565-1568 ◽

Cited By ~ 6

Author(s):

Kazuhiko Iwai ◽

Jun Akiyama ◽

Shigeo Asai

Keyword(s):

Magnetic Field ◽

High Magnetic Field ◽

Slip Casting ◽

Casting Process ◽

Ceramic Materials ◽

X Ray Diffraction ◽

X Ray ◽

Structure Control ◽

Crystal Alignment ◽

The Magnetic Field

A high magnetic field is a useful tool to control the crystal alignment of ceramic materials. In this study, a horizontal 10T static magnetic field was imposed on slurry containing hydroxyapatite (HAp) crystals under the horizontal mold rotation during slip casting process so as to introduce uni-axial alignment for some amount of crystals in the sample, and then it was sintered in atmosphere without the magnetic field. From X-ray diffraction, it has been found that the HAp crystals in the sample treated with the mold rotation under the magnetic field were aligned its c-axis to a particular direction.

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Formation of c-Axis Aligned Hydroxyapatite Sheet by Simultaneous Imposition of High Magnetic Field and Mold Rotation During Slip Casting Process

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.309-311.53 ◽

2006 ◽

Vol 309-311 ◽

pp. 53-56 ◽

Cited By ~ 1

Author(s):

Jun Akiyama ◽

Masami Hashimoto ◽

Hiroaki Takadama ◽

Fukue Nagata ◽

Yoshiyuki Yokogawa ◽

...

Keyword(s):

Magnetic Field ◽

Magnetic Materials ◽

High Magnetic Field ◽

Static Magnetic Field ◽

Slip Casting ◽

Casting Process ◽

Field Direction ◽

Magnetic Field Direction ◽

Hydroxyapatite Crystal ◽

Crystal Alignment

A high magnetic field is a useful tool to control the crystal alignment of non-magnetic materials such as ceramics and polymers. In the case of Hydroxyapatite crystal, the a,b-axis is aligned parallel to the direction of an imposed magnetic field. This fact implies that the alignment of the c-axis is not controllable only using a high static magnetic field due to the freedom of the c-axis in a plane perpendicular to a magnetic field direction. In this study, a high static magnetic field and mold rotation was simultaneously so applied during a slip casting process as to align the c-axis of HAp poly crystals.

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Beta tricalcium phosphate ceramics with controlled crystal orientation fabricated by application of external magnetic field during the slip casting process

Materials Science and Engineering C ◽

10.1016/j.msec.2013.03.024 ◽

2013 ◽

Vol 33 (5) ◽

pp. 2967-2970 ◽

Cited By ~ 14

Author(s):

Takeshi Hagio ◽

Kazushige Yamauchi ◽

Takenori Kohama ◽

Toshiya Matsuzaki ◽

Kazuhiko Iwai

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

Tricalcium Phosphate ◽

Crystal Orientation ◽

Slip Casting ◽

Casting Process ◽

Beta Tricalcium Phosphate

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Preparation and Properties of Al2O3-Mullite-SiC Nano-Composite by Slip Casting in a High Magnetic Field and Reaction Sintering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.1133 ◽

2007 ◽

Vol 336-338 ◽

pp. 1133-1136 ◽

Cited By ~ 1

Author(s):

Sho Saito ◽

Yoshio Sakka ◽

Tohru Suzuki ◽

Takeshi Nakata

Keyword(s):

Magnetic Field ◽

High Magnetic Field ◽

Bending Strength ◽

Slip Casting ◽

Scanning Electron Micrographs ◽

Reaction Sintering ◽

X Ray Diffraction ◽

Three Point Bending ◽

Degree Of Orientation ◽

Diffraction Patterns

We have demonstrated that textured Al2O3-mullite-SiC nanocomposites can be fabricated by slip casting followed by partial oxidation – reaction sintering of mixed suspensions of Al2O3 and SiC powders in a high magnetic field. The sintered density was changed by the degree of oxidation at 1200 and 1300. The degree of orientation of alumina in the nanocomposite was examined on the basis of the X-ray diffraction patterns and scanning electron micrographs. It is confirmed that alumina-oriented nanocomposites were fabricated. The three-point bending strength at room temperature was observed for the nanocomposites.

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Improvement of Second-Order Optical Nonlinearity in Transparent Ba2TiGe2O8 Crystallized Glasses Prepared in High Magnetic Field

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.11-12.193 ◽

2006 ◽

Vol 11-12 ◽

pp. 193-196 ◽

Cited By ~ 1

Author(s):

Nozomu Toyohara ◽

Yasuhiko Benino ◽

Takumi Fujiwara ◽

Satoshi Tanaka ◽

Keizo Uematsu ◽

...

Keyword(s):

Magnetic Field ◽

High Magnetic Field ◽

Crystal Orientation ◽

Glass Matrix ◽

Crystallization Process ◽

Second Harmonic ◽

Optical Nonlinearity ◽

Second Order ◽

Harmonic Intensity ◽

The Magnetic Field

A high magnetic field of H = 10 T was applied to 30BaO-15TiO2-55GeO2 glass through its crystallization process. It was found that the c-axis of Ba2TiGe2O8 optical nonlinear/ferroelectric crystals oriented along the magnetic field. The second harmonic intensity of crystallized glass which the high magnetic field was applied perpendicular to the surface of glass was enhanced compared with a conventional crystallization in no magnetic field. Transparencies, photorefractive indices and thicknesses were also measured. As a result, crystal orientation of Ba2TiGe2O8 in glass matrix induced by a high magnetic field causes improvement of transparency and low value of photorefractive index.

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Preparation of Textured Li1+x-yNb1-x-3yTix+4yO3 Solid Solution in a High Magnetic Field

Materials Science Forum ◽

10.4028/www.scientific.net/msf.783-786.2480 ◽

2014 ◽

Vol 783-786 ◽

pp. 2480-2484 ◽

Cited By ~ 3

Author(s):

Hiromi Nakano ◽

Shiho Suehiro ◽

Tohru S. Suzuki

Keyword(s):

Magnetic Field ◽

Electron Microscope ◽

Strong Magnetic Field ◽

Slip Casting ◽

Cold Isostatic Pressing ◽

X Ray Diffraction ◽

Transmission Electron ◽

M Phase ◽

High Orientation ◽

The Magnetic Field

In the Li2O-Nb2O5-TiO2 system, Li1+x-yNb1-x-3yTix+4yO3 (0.06  x  0.33, 0  y  0.09) (LNT) forms with a superstructure, which is the so-called M-phase. In this work, as a first step toward application of the unique qualities of an electro-ceramic with an anisotropic structure, we prepared an oriented LNT balk ceramic by slip casting in a strong magnetic field of 12 T. The direction of the magnetic field was parallel to the casting direction. The compact was densified by cold isostatic pressing and then heated at 1373 K. The obtained specimen was analyzed by X-ray diffraction, scanning electron microscope, and transmission electron microscope. Consequently, the c-axis of the LNT powders was aligned parallel to the magnetic field and a high orientation degree was achieved in a strong magnetic field of 12 T

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Formation of c-Axis Aligned Hydroxyapatite Sheet by Simultaneous Imposition of High Magnetic Field and Mold Rotation During Slip Casting Process

Bioceramics 18 - Key Engineering Materials ◽

10.4028/0-87849-992-x.53 ◽

2006 ◽

pp. 53-56

Author(s):

Jun Akiyama ◽

Masami Hashimoto ◽

Hiroaki Takadama ◽

Fukue Nagata ◽

Yoshiyuki Yokogawa ◽

...

Keyword(s):

Magnetic Field ◽

High Magnetic Field ◽

Slip Casting ◽

Casting Process

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Diurnal variation effect in marine magnetometric surveys: clues from surveys in southeast Brazil

Marine Geophysical Research ◽

10.1007/s11001-021-09449-7 ◽

2021 ◽

Vol 42 (3) ◽

Author(s):

Paula Possamai Sergipe ◽

Yára Regina Marangoni ◽

Roberto Paulo Zanon dos Santos ◽

Denise Silva de Moura ◽

Luigi Jovane

Keyword(s):

Magnetic Field ◽

Continental Shelf ◽

Diurnal Variation ◽

Brazilian Coast ◽

Observatory Data ◽

Before And After ◽

Corrected Data ◽

Well Correlation ◽

The Magnetic Field ◽

Magnetic Observatories

AbstractThe diurnal variation of the magnetic field cannot be predicted or modeled and for that reason, it is monitored during the magnetic surveys, usually by a stationary magnetometer. However, marine surveys have a practical issue with diurnal monitoring, owing to the distance between the survey, stationary magnetometers, and magnetic observatories. This work aims to verify the use of nearby magnetic observatories to estimate the diurnal variation correction in different marine surveys and evaluate its effectiveness. In this study, we selected surveys at the continental shelf near Santos city (Survey 1), continental slope next to the first survey location (Survey 2), continental shelf near Ubatuba city (Survey 3), and Mamanguá ria in the Paraty city (Survey 4), all southeast to the Brazilian coast. The crossing points were implemented to compare the magnetic field values at different times and days at the same measurement point, before and after the correction. Afterwards, we measure the Pearson’s Correlation of the raw data and the diurnal corrected data in all crossing points of each survey which showed an improvement after correction by the value approximating to 1, which indicates a very well correlation. The Ubatuba and Mamanguá surveys allowed comparing the observatory correction results with the base magnetometer results that were rather similar. Our analyses indicate a satisfactory diurnal correction using the observatory data and the crossing points approach, which can be used for every marine magnetometric survey worldwide placed near the coast (< 280 km) that do not have a stationary magnetometer available.

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Design of Alumina/Alumina Laminate Composites with Crystalline-Orientated Layers Produced by Electrophoretic Deposition under a High Magnetic Field

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.314.25 ◽

2006 ◽

Vol 314 ◽

pp. 25-32

Author(s):

Tetsuo Uchikoshi ◽

Tohru Suzuki ◽

Hideo Okuyama ◽

Yoshio Sakka

Keyword(s):

Magnetic Field ◽

Electrophoretic Deposition ◽

Orientation Angle ◽

Layer By Layer ◽

Alumina Ceramics ◽

X Ray Diffraction ◽

Laminate Composites ◽

Laminar Composites ◽

The Magnetic Field ◽

Oriented Layers

Highly crystalline-textured alumina ceramics were fabricated by electrophoretic deposition (EPD) in a strong magnetic field of 12 T. Preferred orientation of the bulk was controlled by changing the direction of the applied electric field E relative to the magnetic field B during the EPD. Average orientation angle of the prepared monoliths as a function of the angle between the vectors E and B, ϕ B-E was estimated from the X-ray diffraction analysis. Alumina/alumina laminar composites with crystalline- oriented layers were also fabricated by alternately changing the ϕ B-E layer by layer during EPD in a magnetic field of 12 T.

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