The ferrofluid dynamics theory is applied to thermodiffusive problems in magnetic fluids in the presence of magnetic fields. The analytical form for the magnetic part of the chemical potential and the most general expression of the mass flux are given. By applying these results to experiments, global Soret coefficients in agreement with measurements are determined. An estimate for a hitherto un...

A magnetic field rotating on the free surface of a ferrofluid layer is shown to induce considerable fluid motion towards the direction the field is rolling. The measured flow velocity i) increases with the square of the magnetic field amplitude, ii) is proportional to the thickness of the fluid layer, and iii) has a maximum at a driving frequency of about 3 kHz. The pumping speed can be estimat...

1 Esfera UAB, Institut de Microelectrònica de Barcelona IMB-CNM (CSIC), Bellaterra, Spain, 2Department of Pharmacology, University of Sevilla, Sevilla, Spain, 3 Faculty of Medicine and Health Sciences, Basic Sciences Department, Universitat Internacional de Catalunya, Barcelona, Spain, 4 Departament de Física, Institució Catalana de Recerca i Estudis Avançats (ICREA), Universitat Autònoma de Ba...

We present extensive Monte Carlo simulations for the thermodynamic and structural properties of a planar bilayer of dipolar hard spheres for a wide range of densities, dipole moments, and layer separations. Expressions for the stress and pressure tensors of the bilayer system are derived. For all thermodynamic states considered, the interlayer energy is shown to be attractive and much smaller t...

Abstract: Effective and rapid mixing is essential for various chemical and biological assays. The present work reports a simple and low-cost micromixer based on magnetofluidic actuation. The device takes advantage of magnetoconvective secondary flow, a bulk flow induced by an external magnetic field, for mixing. A paramagnetic stream of diluted ferrofluid and a non-magnetic stream are introduce...

Spruce sawdust (lignocellulose material) was magnetically modified after contact with a water-based magnetic fluid containing maghemite nanoparticles. This procedure allows one to use the prepared material as a new magnetic affinity adsorbent in magnetic separation techniques. The magnetic sawdust was investigated by means of electron spin resonance spectroscopy and conventional magnetic method...

Manipulation of small-scale matter is a fundamental topic in micro and nanorobotics. Numerous magnetic robotic systems have been developed for the manipulation microparticles an ambient environment, liquid, as well on air-liquid interface. These move intrinsically or magnetically tagged objects by inducing torque force. However, most materials found nature are nonmagnetic. Here, we report ferro...