|1.Research Institution||Tokyo Metropolitan University|
|2.Research Area||Integrated Fields|
|3.Research Field||Behavior of Substances and Organisms under High Magnetic Field|
|4.Term of Project||FY 1999 - FY 2003|
|6.Title of Project||Effects of Magnetic Field on Fine Particles, Molecular Chains, and Membranes|
|Name||Institution,Department||Title of Position|
|Tsunehisa, Kimura||Tokyo Metropolitan University, Graduate School of Engineering||Professor|
|Names||Institution,Department||Title of Position|
|Hitoshi, Watarai||Osaka University, Graduate School of Science||Professor|
9.Summary of Research Results
Magnetic effects on fine particles, molecular chains, and thin film processing were investigated. The materials of interest in this project are not ferromagnetic, but feeble magnetic materials. Basic research as well as application-oriented researches were carried out.
It was demonstrated that fine particles of polymeric, ceramics, and biological materials are aligned and assembled using magnetic torque and magnetic force. Intensive study on the rotation mechanism of anisotropic materials suspended in a liquid was carried out, where hydrodynamic and field-rotation effects were taken into account.
A new mechanism of magnetic alignment of crystalline polymers was proposed. Unlike the conventional one (rotation by magnetic torque), this new mechanism attributes the alignment to the preferential formation of a specific phase that aligns parallel to the applied field. Examination of this hypothesis is now under way. This hypothesis is plausible in view of the results with precision thermal analysis in the magnetic field developed in this project.
Aligned ceramics was prepared by slip casting in the magnetic field, followed by sintering. Obtained samples exhibited high dielectric properties. Optical methods for the determination of the alignment was developed.
Diamagnetic particles including polymer spheres and cells are patterned at micrometer order using a field modulator inserted in a homogeneous magnetic field. This patterning method will open a new means of trapping and patterning fine particles down to nano meter orders.
Analytical methods using magnetic fields have been developed, enabling particle analysis and precision analysis of liquid droplets. This method would be used to the analyses of biological particles such as cells, DNA, etc.