The atomic level structure of a series of monodisperse single crystalline nanoparticles with a magnetic core of manganese ferrite was studied using X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) techniques at both the Fe and Mn K-edges, and conventional and high resolution transmission electron microscopy (TEM and HRTEM). In particular, insights on the ...

calcium doped nickel ferrite powders have been prepared by sol-gel combustion technique. metal nitrates, such as calcium nitrate, nickel nitrate and ferric nitrate, were used as the source materials and citric acid and polyvinyl alcohol were used as the burning agent and agglomeration reducing agent, respectively. the average crystallite size of the prepared ferrite was in the order of ~70- 92 ...

Magnetite nanoparticles combined with polymers produce white-light emission under multiphoton laser irradiation. Understanding the photonic reaction in magnetite-polymer composites is critical for application of magnetite NPs as photothermal agents. Laser irradiated magnetite nanoparticle-poly(methyl methacrylate) (PMMA) composites exhibit fluorescence due to the carbon double-bond formation re...

The contamination of sulfur emanating from pyrrhotite in magnetite concentrates has been a problem in iron ore processing. This study utilized froth flotation to float pyrrhotite away from magnetite using collectors of xanthate and dixanthogen. It was found that xanthate or dixanthogen alone could not achieve selective separation between pyrrhotite and magnetite in flotation. A high loss of mag...

Significant magnetite, in the form of dyke-like lodes (Cockfield. 1948). occurs in close spatial relationship to copper deposits such as the Afton mine. The genetic relationship of these massive magnetite lodes to the copper deposits of the Iron Mask is unknown, as i s the origin of the magnetite deposits. However, the proximity of these deposits to magnetite-rich intrusive units of the Iron Ma...

Background and Introduction: The question of the origin of nanophase magnetite in Martian meteorite ALH84001 has been widely debated for nearly a decade. Golden et al. [1] have reported producing nearly chemically pure magnetite from thermal decomposition of chemically impure siderite [(Fe, Mg, Mn)CO3]. This claim is significant for three reasons: first, it has been argued that chemically pure ...

The first evidence is provided for the existence of a tetragonal or slightly orthorhombic unit cell of bainitic ferrite. It supports the hypothesis that the excess carbon that persists in the ferrite, which is in contact with austenite, is a consequence of an increased solubility due to the change in symmetry from the conventional cubic unit cell. The deviations from the cubic cell are maintain...

Duplex stainless steel multi-pass welds were made at 0.15 MPa, 0.45 MPa, and 0.75 MPa pressure, simulating underwater dry hyperbaric welding by the flux-cored arc welding (FCAW) method, with welds of normal pressure as a benchmark. The purpose of this work was to estimate the effect of ambient pressure on the microstructure, pitting corrosion resistance and impact toughness of the weld metal. T...

Nanofluids are composed of nano-sized particles dispersed in a carrier liquid. The present investigation’s aim is to examine theoretically the magneto-thermomechanical coupling phenomena heated nanofluid on stretched surface presence magnetic dipole impact. Fourier’s law heat conduction used evaluate transmission rate fluids ethylene glycol and water along with suspended nanoparticles cobalt–ch...

A large number of unexploited low-grade vanadium-titanium magnetite deposits have been found in the Chao-yang area of China in recent years. The reserves are estimated at more than 20 billion tons. A mineralogical study of raw sample indicated that it was a typical low-grade vanadium-titanium magnetite ore with weathering. Most of vanadium-titanium magnetite was replaced by martite and sphene, ...