This study develops analytical relationships and computations of power dissipation in magnetic fluid (ferrofluid) subjected to alternating magnetic field. The dissipation results from the orientational relaxation of particles having thermal fluctuations in a viscous medium. r 2002 Elsevier Science B.V. All rights reserved.

background: magnetic nanoparticles in a variable magnetic field are able to produce heat. this heat (42-45°c) has more selective effect on fast dividing cancer cells than normal tissues. methods: in this work magnetite nanoparticles have been prepared via co-precipitation and phase identification was performed by powder x-ray diffraction (xrd). magnetic parameters of the prepared nanoparticles ...

A new mechanism of cell damage by alternating magnetic field with hematoporphyrin is described. C6 glioblastoma cell suspensions were exposed to an alternating magnetic field with frequency 180 kHz up to 60 min in the presence of hematoporphyrin in H2O and in D2O. The results presented suggest that an alternating magnetic field is able to activate hematoporphyrin, and this method may be a basis...

magnetic cufe2o4 nanoparticles were synthesized by a facile microwave-assisted reaction between cu(no3)2 and fe(no3)3. the magnetic nanoparticles were added to starch to make magnetic polymeric nanocomposite. the nanoparticles and nanocomposites were characterized using x-ray diffraction and scanning electron microscopy. the magnetic properties of the samples were investigated using an alternat...

concurrent hyperthermia and radiation therapy in treatment of cancer show a strong evidence of a synergistic enhancement. we designed a new self-regulating thermo-brachytherapy seed, which serves as a source of both radiation and heat for concurrent administration of brachytherapy and hyperthermia. the thermo-brachytherapy seed has a core of ferromagnetic material which produces heat when subje...

the lead ferrite (pbfe12o19) nanoparticles were prepared by a simple and short time microwave method. lead nitrate, iron nitrate hydrate, surfactants, and ethylene glycol were used as precursor materials. the effect of surfactants on the morphology and particle size of the magnetic products was investigated. the prepared magnetic products were study by x-ray diffraction (xrd), scanning electron...

Dipolar interactions between nano- and micron sized colloids lead to their assembly into domains with well-defined local order. The particles with a single dipole induced by an external field assemble into linear chains and clusters. However, to achieve the formation of multidirectionally organized nano- or microassemblies with tunable physical characteristics, more sophisticated interaction to...

We investigate the Hubbard Hamiltonian on ladders where number of sites per rung alternates between two and three. These geometries are bipartite with nonequal or equal sublattices. Thus they share a key feature model in class lattices which Lieb has shown analytically to exhibit long-range ferrimagnetic order while being amenable powerful numeric approaches developed for quasi-one-dimensional ...

The effect of alternating magnetic field at extremely low frequency on secretion of insulin from beta cells has been investigated in vitro. Beta cells from a hamster were exposed to the uniform magnetic field with the Helmholtz coil. After three days cultivation, insulin concentration in the medium was measured. The experimental results show that secretion of insulin by beta cells tend to decre...