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Showing 1 to 14 of 14 for “"maghemite"”.
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Application of Mixed Iron Oxides in Subsurface Remediation Technologies
… from groundwater. In the present study, mixed maghemite-magnetite nanoparticles have been used as adsorbents for Cr(VI), As and Cd(II) removal. From the study, it is apparent that the removal of Cr(VI ), Cd(II) and As(V) by mixed iron oxide nanoparticles depends on pH, temperature, contact …
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Magnetite Oxidation in Aqueous Systems
… one of its oxidation transformation products, maghemite, by the use of UV-Vis-NIR spectroscopy. As oxidation proceeded at a constant specific temperature, the concentration of magnetite decreases, which was indicated by a decrease in absorption in the NIR-region of the spectrum. As magnetite …
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Magnetic iron oxide nanoparticles: synthesis, characteristics, magnetic behavior, and biomedical applications
… most common iron oxides, including magnetite and maghemite, are discussed in this thesis. For most of their applications, the magnetic behavior of iron oxide nanoparticles in a fluid is very important, especially, the high gradient magnetic separation of the particles from a nonmagnetic liquid …
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Synthesis and characterisation of metal oxides and metal doped variants
… transformation to structurally related tin-doped maghemite before undergoing a structural transformation to tin-doped hematite. A lowering of the Curie temperature for both the tin-doped maghemite and and tin-doped hematite has been identified. <br></br><br></br>Chromium- and gallium- doped …
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Formation and alteration of magnetite nanoparticles
… of the oxide, because magnetite oxidizes to maghemite under environmental conditions. The dynamics of this process have not been well described. Smaller nanoparticles are shown to oxidize more rapidly than larger ones and the lower the storage temperature, the lower the measured oxidation. In …
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Implications of Oxidation on the Colloidal Stability of Magnetite Nanoparticles and Cluster
… magnetite readily reacts with O2 to produce maghemite, we analyzed the effect of oxidation on its magnetic properties. We observed that oxidation caused a decrease in the saturation magnetization and the anisotrophic barrier of magnetite resulting in less significant magnetic interactions …
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Colloidal CoFe2O4-based nanoparticles for Magnetic Fluid Hyperthermia
… less toxic isostructural phases (i.e. magnetite/maghemite or manganese ferrite).
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Síntese e caracterização de nanopartículas de óxidos de ferro e sua mistura com resíduos da cana-de-açúcar (bagaço e palha) para emprego nos processos de adsorção e fotocatálise heterogênea
… oxide composites, in which they presented maghemite and/or magnetite phases, as determined by X-ray Diffraction. The results of heterogeneous photocatalysis and adsorption tests of methylene blue (with values of up to 90%) showed that the composite materials are efficient photocatalysts and …
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Magnetism of anthropogenic airborne particulate matter
… that the LU is dominated by ultrafine (<100 nm) maghemite particles. The oxidised nature of the magnetic PM suggests that PM exposure in the LU is dominated by resuspension of aged dust particles relative to freshly abraded, metallic particles from the wheel-track-brake system. Therefore, I …
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"Smart" Hydrogels based on Trishydrophilic Triblock Terpolymers
… with negatively charged, citrate stabilized maghemite (γ-Fe(III)-oxide) nanoparticles. Using different analytical methods it was shown that well-defined CSC hybrid micelles were obtained with cores formed by a complex of P2VP and 3-4 nanoparticles per core. Concentrated solutions of these …
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Investigation of the promotional effect of Cu and Ag on iron-based Fischer-Tropsch catalysts using ferrites as model catalysts
… the iron catalyst. The results are compared to maghemite (γ-Fe2O3) and hematite (α-Fe2O3). The presence of group 11 metals in the crystal structure facilitates the reduction of trivalent iron into magnetite during catalyst activation in either hydrogen or carbon monoxide and the consecutive …
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Nanoscale thermal transport for biological and physical applications
… We show that iron-platinum, magnetite, and maghemite are viable MFH candidates since they are able to provide the desired heating of a tumor which will destroy it while keeping the surrounding healthy tissues at a relatively safe temperature. Recent advances in the synthesis and …
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Chemistry of Nanoscale Solids and Organic Matter in Sustainable Water Management Systems
… minerals, such as iron(III) (hydr)oxide (maghemite, _-Fe2O3) and iron(III) phosphate (phosphosiderite, FePO4塲H2O), helped to decrease arsenic mobility through re-adsorption. Over the entire 7-day reaction, silicate increased arsenic mobility, and bicarbonate decreased arsenic mobility in …