Ferrofluid instabilities in DC magnetic fields for an Isopar-M based ferrofluid with saturation magnetization of about 400 Gauss. a) 1200 Gauss 5 mm diameter magnet behind small ferrofluid droplet surrounded by propanol to prevent ferrofluid wetting of 1 mm gap glass plates; Peak pattern with magnetic field perpendicular to ferrofluid layer. The peaks initiate in a hexagonal array when the magn...

In the presence of an external magnetic field, cobalt nanoparticle-based ferrofluid forms a self-assembled hyperbolic metamaterial. The wave equation, which describes propagation of extraordinary light inside the ferrofluid, exhibits 2+1 dimensional Lorentz symmetry. The role of time in the corresponding effective three-dimensional Minkowski space-time is played by the spatial coordinate direct...

The aim of the present investigation is to explain the application of ferrofluid (Fe3O4) as target drug delivery system in nanotechnology. It works on the principle of Magnetism which plays an important role in different application of ferrofluid in medicine. Ferrofluid is biocompatible and therefore it is one of the most extensively used biomaterials for different application ranging from cell...

This paper presents a general method for studying the mechanical properties of a ferrofluid seal by using a three-dimensional analytical approach based on the coulombian model of a magnet. The fundamental Maxwell’s equations lead us to define the concept of magnetic energy of the ferrofluid seal by using only the three-dimensional equations of the magnetic field created by ring permanent magnet...

Fluid control is a key element in the performance of microfluidic “lab-on-a-chip” devices. The development of integrated multi-function micro-chemical reactors and analysis platforms depends upon on-chip valving and pumping. In this work, microfluidic valves and pumps were fabricated from etched glass substrates each bonded to a second glass substrate lid that had ultrasonically drilled access ...

Two measurement techniques to determine the surface tension of ferrofluids using the perpendicular field instability are described. Four ferrofluid layers were examined with magnetic field applied perpendicularly to the surface of s1d oil-based ferrofluid in air; s2d water-based ferrofluid in air, s3d oil-based ferrofluid, and s4d fluorocarbon-based ferrofluid, both below a blend of 50% n-Propy...

Magnetic field based micro/nanoelectromechanical systems (MEMS/NEMS) devices are proposed that use 10 nm diameter magnetic particles, with and without a carrier fluid, for a new class of nanoduct flows, nanomotors, nanogenerators, nanopumps, nanoactuators, and other similar nanoscale devices. A few examples of macroscopic ferrohydrodynamic instabilities that result in patterns, lines, and struc...

This paper presents three dimensional study of a ferrofluid seal, its centering effect and its static capacity. Thus, a method based on a potential energy criterion has been put forward to study the seal shape. But such a use of ferrofluid seals is interesting only if the magnetic field created by the permanent magnets saturates totally the ferrofluid. Two cylindrical structures consisting of t...

We present an electromagnetic linear vibration energy harvester with an array of rectangular permanent magnets as a springless proof mass. Instead of supporting the magnet assembly with spring element, ferrofluid has been used as a lubricating material. When external vibration is applied laterally to the harvester, magnet assembly slides back and forth on the channel with reduced friction and w...

Analyses and measurements have shown anomalous behavior of ferrofluids in alternating and rotating magnetic fields, including flow reversals and negative magnetoviscosities as a function of magnetic field amplitude and frequency. These experiments measure the ferrofluid viscous torque on a rotating cylinder while varying the magnetic field amplitude and frequency, thereby confirming the strong ...