Based on a self-assembly strategy, spherical mesoporous cobalt and nickel ferrite nanocrystal clusters with a large surface area and narrow size distribution were successfully synthesized for the first time via a template-free solvothermal process in ethylene glycol and subsequent heat treatment. In this work, the mesopores in the ferrite clusters were derived mainly from interior voids between...

The presence of isotopically light carbonates in association with fine-grained magnetite is considered to be primarily due to the reduction of Fe(III) by Fe(III)-reducing bacteria in the environment. Here, we report on magnetite formation by biooxidation of Fe(II) coupled to denitrification. This metabolism offers an alternative environmental source of biogenic magnetite.

Abstract. The magnetic properties of magnetite nanoparticles and magnetite-thermoplastic natural rubber (TPNR) nanocomposites was prepared by melt-blending method has been studied using vibrating sample magnetometer (VSM). The saturation magnetization (MS), remanence (MR), squareness (MR/MS), coercivity (HC) and exchange-bias field (Heb) for magnetite nanoparticles and its nanocomposites increa...

Next generation magnetic microwave devices will be planar, smaller, weigh less, and perform well beyond the present state-of-the-art. For this to become a reality advances in ferrite materials must first be realized. These advances include self-bias magnetization, tunability of the magnetic anisotropy, low microwave loss, and volumetric and weight reduction. To achieve these goals one must turn...

In recent years, with the wide application of image data visual extraction technology in field industrial engineering, development economy has reached a new situation. To explore interaction between pellet microstructure and compressive strength, firstly, needed for experiment was obtained using Leica DM4500P microscope. The area proportions hematite, calcium ferrite, magnetite, silicate pore w...

Long range dipole-dipole correlation in a ferromagnetic sample can be treated in terms of collective excitations of the system as a whole. Ferrite samples with linear dimensions smaller than the dephasing length, but still much larger than the exchange-interaction scales, are mesoscopic structures. Recently, it was shown that mesoscopic quasi-2D ferrite disks, distinguishing by multiresonance m...

Knowledge of carbon content in retained austenite (RA) with different neighbouring phases is essential to understand the chemical stability of RA, which is useful for microstructure tuning of transformation-induced plasticity (TRIP) steels. The present study investigates different morphologies and chemical compositions of RA by correlating electron backscattering diffraction, transmission elect...

Hematite fines were found to form aggregates with magnetite ~des in the same slurry, without the help of any flocculants. Because of this aggregation. fine iron ores containing hematite and -anetile can be successfully concentrated by multi-stage deslimings. ~ that the ore is finely ground and silicate gangues properly ~rsed. The effectiveness of this technique has been tested on a UMIIIIIercia...