132 Study on the Flow Pattern Induced by Micro Liquid Bridge Oscillation of Magnetic Fluid in Water

This paper describes a new discrimination technique of flow regime (flow pattern) for gas—liquid two-phase flow in magnetic fluid. The proposed technique can identify the flow regime with simple devices by exploiting the wave patterns of signals obtained by electromagnetic induction. This utilization achieves a mechanically non-contact measuring method for objective fluids. In this study, verification experiments for practical measurement were conducted in upward gas—liquid two-phase flow. The results of the experiments have verified that the proposed measuring technique is useful as a method for flow regime discrimination.

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The dynamic behaviour of a micro liquid bridge of magnetic fluid in static and alternating magnetic fields

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-141813 ◽

2014 ◽

Vol 45 (1-4) ◽

pp. 61-67

Author(s):

Seiichi Sudo ◽

Hiroki Takamatsu ◽

Tetsuya Yano ◽

Hidemasa Takana ◽

Hideya Nishiyama

Keyword(s):

Magnetic Fields ◽

Magnetic Fluid ◽

Liquid Bridge ◽

Dynamic Behaviour ◽

Alternating Magnetic Fields

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A magnetic super lattice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126597 ◽

1987 ◽

Vol 45 ◽

pp. 360-361 ◽

Cited By ~ 1

Author(s):

M.D. Bentzon ◽

J. v. Wonterghem ◽

A. Thölén

Keyword(s):

Thermal Decomposition ◽

Oleic Acid ◽

Magnetic Fluid ◽

Magnetic Particles ◽

Carbon Film ◽

Thick Layer ◽

Amorphous Iron ◽

Super Lattice ◽

Carrier Liquid ◽

Median Diameter

We report on the oxidation of a magnetic fluid. The oxidation results in magnetic super lattice crystals. The “atoms” are hematite (α-Fe2O3) particles with a diameter ø = 6.9 nm and they are covered with a 1-2 nm thick layer of surfactant molecules.Magnetic fluids are homogeneous suspensions of small magnetic particles in a carrier liquid. To prevent agglomeration, the particles are coated with surfactant molecules. The magnetic fluid studied in this work was produced by thermal decomposition of Fe(CO)5 in Declin (carrier liquid) in the presence of oleic acid (surfactant). The magnetic particles consist of an amorphous iron-carbon alloy. For TEM investigation a droplet of the fluid was added to benzine and a carbon film on a copper net was immersed. When exposed to air the sample starts burning. The oxidation and electron irradiation transform the magnetic particles into hematite (α-Fe2O3) particles with a median diameter ø = 6.9 nm.

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Morphology and development of flow-pattern defect with extended nonagitated Secco etching

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100172073 ◽

1994 ◽

Vol 52 ◽

pp. 868-869

Author(s):

Y. Pan

Keyword(s):

Flow Pattern ◽

Silicon Crystal ◽

Gate Oxide ◽

Crystal Growth Rate ◽

Etch Depth ◽

Force Microscopy ◽

Etch Pit ◽

Float Zone ◽

Atomic Force ◽

Multiple Step

The D defect, which causes the degradation of gate oxide integrities (GOI), can be revealed by Secco etching as flow pattern defect (FPD) in both float zone (FZ) and Czochralski (Cz) silicon crystal or as crystal originated particles (COP) by a multiple-step SC-1 cleaning process. By decreasing the crystal growth rate or high temperature annealing, the FPD density can be reduced, while the D defectsize increased. During the etching, the FPD surface density and etch pit size (FPD #1) increased withthe etch depth, while the wedge shaped contours do not change their positions and curvatures (FIG.l).In this paper, with atomic force microscopy (AFM), a simple model for FPD morphology by non-crystallographic preferential etching, such as Secco etching, was established.One sample wafer (FPD #2) was Secco etched with surface removed by 4 μm (FIG.2). The cross section view shows the FPD has a circular saucer pit and the wedge contours are actually the side surfaces of a terrace structure with very small slopes. Note that the scale in z direction is purposely enhanced in the AFM images. The pit dimensions are listed in TABLE 1.

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