Humic substances (HS) are redox-active compounds that are ubiquitous in the environment and can serve as electron shuttles during microbial Fe(III) reduction thus reducing a variety of Fe(III) minerals. However, not much is known about redox reactions between HS and the mixed-valent mineral magnetite (Fe3O4) that can potentially lead to changes in Fe(II)/Fe(III) stoichiometry and even dissolve ...

Cast strips of 0.1mass% C steel with or without phosphorus addition have been characterized by electron back-scattering diffraction pattern (EBSP) measurements. Then the formation of globular ferrite structure was discussed. EBSP analysis combined with optical microscopy clearly showed that a globular grain was fitted to be an -ferrite grain. The EBSP analysis suggested that the retainedgrain g...

The manganese ferrite spinel was synthesized by co-precipitation. The nano sized manganese ferrite characterized by X-ray diffraction (XRD), Scanning electron micrograph (SEM), tunneling electron micrograph (TEM) and Energy dispersive X-ray (EDX) techniques. The adsorption ability of malachite green (MG) from the aqueous solution by manganese ferrite was investigated. It was found that pH value...

Ž . Although dissimilatory iron reducing bacteria DIRB are capable of reducing a number of metals in oxides and soluble forms, the factors controlling the raterextent of magnetite reduction and the nature of the mineral products resulting from magnetite reduction are not well understood. This study was carried out to investigate mechanisms and biogeochemical processes occurring during magnetite...

The optical properties of multi-functionalized cobalt ferrite (CoFe2O4), cobalt zinc ferrite (Co0.5Zn0.5Fe2O4), and zinc ferrite (ZnFe2O4) nanoparticles have been enhanced by coating them with silica shell using a modified Stöber method. The ferrites nanoparticles were prepared by a modified citrate gel technique. These core/shell ferrites nanoparticles have been fired at temperatures: 400°C, 6...

Distinct morphological characteristics of magnetite formed intracellularly by magnetic bacteria (magnetosome) are invoked as compelling evidence for biological activity on Earth and possibly on Mars. Crystals of magnetite produced extracellularly by a variety of bacteria including Geobacter metallireducens GS-15, thermophilic bacteria, and psychrotolerant bacteria are, however, traditionally no...

Nanoindentation measurements were obtained on eight commercially-produced DP980 dual-phase steels to quantify the hardness of the individual constituents, ferrite and martensite, in each steel. Each microstructure was also evaluated to determine grain size, martensite volume fraction (MVF), and retained austenite content. Nanoindentation hardnesses and quantitative microstructural measurements ...

The long-term objective of the present study was to determine the ability of NiZn ferrite nanoparticles to kill cancer cells. NiZn ferrite nanoparticle suspensions were found to have an average hydrodynamic diameter, polydispersity index, and zeta potential of 254.2 ± 29.8 nm, 0.524 ± 0.013, and -60 ± 14 mV, respectively. We showed that NiZn ferrite nanoparticles had selective toxicity towards ...

it is shown how the radiation characteristic of a patch antenna can be manipulated by a small number of normally magnetized ferrite disks inserted in the resonant region of the patch. It is shown that a oneand dual-band circular polarized microstrip antenna can be obtained by taking advantage of the interaction of the antenna cavity field with the magnetized ferrite disks. . The dependence of t...