The teeth of the Polyplacophora Chiton Acanthochiton Rubrolinestus contain biomineralized magnetite crystallites whose biological functions in relation to structure and magnetic properties are not well understood. Here, using superconducting quantum interference device (SQUID) magnetometry, we find that the saturation magnetization (σ(s)) and the Verwey transition temperature (T(v)) of tooth pa...

Magnetite-ENR polymer electrolytes doped with various % wt of LiCF3SO3 salt were synthesized in-situ in the presence of ENR and cast into film doped with LiCF3SO3. XRD results confirmed the purity of the as-formed magnetite particles. The diffraction peaks assigned for LiCF3SO3 become more intense as the concentration of salt is increased. FTIR analyses showed that both “free” (dissociation) an...

Magnetic nanoparticles made of magnetite have the advantage to be biocompatible and to have a good saturation magnetisation. In this work we show that magnetite nanoparticles change their magnetic and chemical characteristics over time, depending on their storage conditions. To determine the oxidation state of the iron in the core of the nanoparticles Mössbauer spectroscopy was used at 4.2 K. T...

The pH-dependent adsorption of humic acid (HA) on magnetite and its effect on the surface charging and the aggregation of oxide particles were investigated. HA was extracted from brown coal. Synthetic magnetite was prepared by alkaline hydrolysis of iron(II) and iron(III) salts. The pH-dependent particle charge and aggregation, and coagulation kinetics at pH approximately 4 were measured by las...

In recent years, a variety of animals have been found which are able to synthesize the ferromagnetic mineral magnetite (Fe 3 O 4). Lowenstam (1962) originally recognized biogenic magnetite in the radular teeth of a primitive marine mollusc, the chiton (Polyplacophora), and since then it has been identified as a precipitate in several magnetically sensitive organisms, including honey bees also r...

The separation factor, aM-0= ( 1 8 0 / 1 6 0 ) magnetite/' ( 1 8 0 / 1 6 0 ) atmospheric oxygen, between the magnetite crust of iron meteorites and atmospheric oxygen has been determined to be 0.9946 ± 0.0005. It is concluded that this fractionation of the oxygen isotopes is the consequence of an equilibrium isotope effect at high temperatures. It can be assumed that this is also valid for cosm...

Water-dispersible Fe(3)O(4) nanoparticles have been prepared by a simple solution method, in which the particle size (3-11 nm) can be tuned by simply adjusting the reaction temperature and time; the formation mechanism of Fe(3)O(4) nanoparticles is proposed and their low cytotoxicity has also been proved.

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