[1] Iron oxide inclusions in pyroxene crystals from the Modipe Gabbro, Botswana, have been studied to determine their recording fidelity. Hysteresis parameters, first-order reversal curves, isothermal remanent magnetization acquisition curves, and thermomagnetic data all indicate that the iron oxide occurs as stoichiometric magnetite …
˚ne and ultrane magnetite and hematite particles will end up in the tailing dams1–4. Flotation separation (direct or reverse) is the most common method for processing iron oxides in a typical
The magnetic properties of certain soils indicate the widespread presence of ultrafine-grained magnetite, even where there is no detrital input of magnetite 1-3 . This suggests that in situformation of magnetite can occur under soil-forming conditions. Schwertmann and Taylor 4 have stated, however, that magnetite has not been found as a newly …
The solvothermal method is used to prepare ultrafine magnetite nanopowders, that is, shape-controlled, monodispersed, and high-crystalline MNPs . This route is conducted to grow dislocation-free single crystal particles. The grains synthesised under this approach possess better crystallinity than those from other approaches [1,13].
Results indicated that ether diamine and monoamine could highly float ultrafine quartz particles (95.9 and 97.7%, respectively) and efficiently separate them from ultrafine magnetite particles.
Here we report the recovery and identification of pure, ultrafine-grained magnetite from some UK soils that have no apparent external source of magnetite.
Besides magnetite, we also observe other Fe-bearing NPs such as rounded crystal NPs only consisting of Fe, Mn, and Ni (Fig. 2h–j and Supplementary Fig. 5) that resemble Fe-Mn-Ni alloy particles ...
A new extraction technique now permits ultrafine magnetite crystals to be separated from a variety of deep-sea sediments. Morphologic characterization of these particles with transmission electron microscopy reveals the presence of several distinct crystal types, some of which closely resemble those formed by the magnetotactic bacteria. The …
The reducing property of pellets prepared by ultrafine magnetite concentrate (UMC) and improving method were revealed. The results show that the reduction degree of UMC pellets is only about 56% ...
tion performance of ultrafine magnetite from the mixture with fine glass beads (ballotini) when, before the pulp is fed into the flotation column, it is mixed with fine air-in-water dispersion, and the mixture is then passed through a tubular flotation reactor (TFR). The obtained experimental
This upsurge of interest in 'environmental magnetism' is based on several factors. First, magnetic measurements of natural materials are highly sensitive; they can detect the …
Ultrafine, superparamagnetic spherical magnetite nanoparticles functionalized by triethylene glycol or polyethylene glycol were successfully synthesized …
Considering both the mathematical difficulty for quantifying the distribution of coercivities and uncertainty concerning the fraction of ultrafine pedogenic magnetite or maghemite in Chinese loess, we presume two different mean coercivities of H c = 25 mT and 30 mT, respectively, with saturation magnetization of J s = 478 kA/m for magnetite …
Here we report the recovery and identification of pure, ultrafine-grained magnetite from some UK soils that have no apparent external source of magnetite. We consider this …
The saturation magnetization of the particles was above 50 emu/g, in spite of their small size and low crystallinity compared with conventionally prepared fine magnetite particles. KW - PVA. KW - saturation magnetization. KW - superparamagnetism. KW - ultrafine magnetite particles
The magnetite Fe3O4 nanoparticles have a broad range of applications due to the combination of specific magnetic and electrical properties. It is important to develop synthesis approaches where ...
number of magnetite particles that attach to the surface of the fine bubbles increases, thus boosting the flotation mechanism of iron entrainment in tailings. In the 4 mm diameter TFR
A novel method of producing PEG-coated magnetite particles has been achieved by the reaction of Si(OR) R′R′′ with colloidal magnetite particles. It has proved …
Ultrafine Magnetite Nanopowder: Synthesis, Characterization, and Preliminary Use as Filler of Polymethylmethacrylate Nanocomposites January 2012 Journal of Nanotechnology 2012(2)
The Gas-solid Fluidized Bed Coal Beneficiator (GFBCB) is an important technology used in the dry coal beneficiation process, which requires lower bed density and very uniform density distribution.
Simple magnetic separation for a certain magnetite mine with ultrafine disseminated lean ores has resulted in low performance, as the fine sizes and aggregation of ground mineral particles have caused inefficient recovery of the ultrafine minerals. In this study, we attempt to increase the apparent sizes of target mineral particles, and improve …
However, the upgrading of ultrafine magnetite flotation was rarely addressed. Chipakwe et al. examined the effect of a polyacrylic acid-based grinding additive (GA) through flotation separation of ...
Here we report the recovery and identification of pure, ultrafine-grained magnetite from some UK soils that have no apparent external source of magnetite.
The reducing property of pellets prepared by ultrafine magnetite concentrate (UMC) and improving method were revealed. The results show that the reduction degree of UMC pellets is only about 56% compared with that of pellets prepared from ordinary iron ore concentrate with relatively coarse particle size, which is …
The morphology, structure and chemical composition of synthesized tin-doped nanoparticles were presented in Fig. 2.The usage of a single-step synthesis method of Sn 4+ doped magnetite nanoparticles allowed to obtain ultrafine, agglomerated Fe 3 O 4:Sn 4+ NPs (Fig. 2 a). The broad rings can be observed in the SAED pattern (Fig. 2 b), which …
1. Introduction. Panzhihua, the largest vanadium–titanium magnetite resource base, provides more than 70% ilmenite for the titanium industry in China [1], [2].Owing to the complex element lattice substitution, the vanadium–titanium magnetite ore in Panzhihua is finely ground to recover the titanium magnetite [3].However, it is worth noting that the …
Herein, we are presenting a single-step 1-minute room-temperature aqueous precipitation synthesis of ultrafine crystalline magnetite nanoparticles by using only a …
Abstract. The magnetic properties of certain soils indicate the widespread presence of ultrafine-grained magnetite, even where there is no detrital input of magnetite1-3. This suggests that in ...
The magnetite Fe3O 4 nanoparticles have a broad range of applications due to the combination of specic magnetic and electrical properties. It is important to develop synthesis approaches where magnetite nanoparticles can be obtained from cheap precursors in large quantities rapidly. Herein, we report a straight-
A new extraction technique now permits ultrafine magnetite crystals to be separated from a variety of deep-sea sediments. Morphologic characterization of these particles with transmission electron microscopy reveals the presence of several distinct cryst al types, some of which closely resemble those formed by the magnetotactic bacteria.
We found that both soils contain 1–30 μm aeolian Fe-oxide grains with indistinguishable rock magnetic properties, while the higher-precipitation soil contains an additional population of ultrafine (<150 nm) …
Application of ultrafine magnetite nanoparticles in different types of water. Individual removal of Pb 2+, Cu 2+, Cd 2+, and Ni 2+ ions from contaminated (a) deionized water and (b) river water.
aggregated with gangue minerals, such as micro-zone 5.Ultrafine magnetite particles below 5 μ m in size are commonly sighted, e.g., in micro-zones 1, 2, 3, and 4, and occasionally there are magnetite
Accordingly, in this study, ultrafine magnetite nanoparticles with a size of about 10 nm and modified surface were synthesized using the polyol method. Organic (polyethylene glycol ...
@article{osti_1583103, title = {Water as the Solvent in the Stober Process for Forming Ultrafine Silica Shells on Magnetite Nanoparticles}, author = {Furlan, Ping Y. and Furlan, Alexander Y. and Kisslinger, Kim and Melcer, Michael E. and Shinn, David W. and Warren, John B.}, abstractNote = {Silica coating of magnetite nanoparticles (MNPs) …
The pH of the magnetite suspension after the end of precipitation was 1.5, 4.0 or 0.6 respectively. The suspension of the ultrafine magnetite particles was prepared by adding the washed particles to a 3 wt.% PYA aqueous solution and then ball-milling with one hundred 16 mm glass balls for 48 h. The ball-milled sample was denoted Mag-OH …