A Kinetic Study on the Reduction of Single Magnetite …
In this study, the reduction characteristics of single magnetite particles with melting products at high temperature were investigated by using visualization and surface analytical techniques. The morphology evolution, product type, reduction degree, and reduction rate of single magnetite particles during the reduction process were analyzed and compared …
Imaging the Magnetization of Single Magnetite …
demonstrate magnetic CD imaging of superparamagnetic magnetite nanoparticulate clusters immersed in microscope immersion oil. The sensitivity of our method …
a behavior of pseudo single-domain magnetite particles …
behavior of pseudo–single-domain magnetite particles Trevor P. Almeida,1*† Adrian R. Muxworthy,1 András Kovács,2 Wyn Williams,3 Paul D. Brown,4 Rafal E. Dunin-Borkowski2 The study of the paleomagnetic signal recorded by rocks allows scientists to understand Earth's past magnetic field and the formation of the geodynamo.
Correlation between particle size/domain structure and …
Highly crystalline single-domain magnetite Fe 3 O 4 nanoparticles (NPs) are important, not only for fundamental understanding of magnetic behaviour, but also for their …
Visualized effect of oxidation on magnetic recording fidelity …
Magnetite (Fe3O4) is an important magnetic mineral to Earth scientists, as it carries the dominant magnetic signature in rocks, and the understanding of its magnetic recording fidelity provides a ...
Searching for single domain magnetite in the "pseudo …
magnetization, M s) or are less sensitive (i.e., coercivity of remanence,B cr)tograinsizevariations.Plotsof variationsin hysteresis data, with M r/M s plotted versus B cr/B c [Day et al., 1977], have therefore become routine accompaniments to published papers in which magnetite grain size is important.
Conductive magnetite nanoparticles trigger syntrophic methane
The collected current profiles under an applied voltage of 0.8 V were depicted over the operation time of a single chamber MES with (MES-M) and without (MES-C) magnetite addition (Fig. 1).Both MESs exhibited current growth after 2 days of inoculation, but MES-M was more efficient in achieving 5.4 mA at the first loading, which was about 2 times higher than that …
Single crystalline superstructured stable single domain …
Here, we synthesize 40 nm particles of magnetite in the presence of polyarginine and show that they are composed of 10 nm building blocks, yet diffract like single crystals.
(PDF) Magnetization Switching of Single Magnetite …
Photothermal CD images of single magnetite nanoparticles, about 20 nm in diameter. A: Photothermal (PT) image; B: CD image without applied static magnetic field; C, D: MCD images with magnetic ...
Single crystalline magnetite, maghemite, and hematite nanoparticles
Abstract. One-pot synthesis of amorphous iron oxide nanoparticles with two different dimensions (<5 nm and 60 nm) has been achieved using the reverse micelle method, with <5 nm …
Single crystalline superstructured stable single domain …
SCIEntIfIC REPORTS 444 D 10.103srep444 1 Single crystalline superstructured stable single domain magnetite nanoparticles Victoria Reichel1, András Kovács2, Monika ...
Solvothermal Synthesis of Single-Crystal Magnetite Hollow …
In this paper, single-crystal magnetite hollow sub-microspheres with a narrow diameter distribution are synthesized through a simple solvothermal process in ethylene glycol in the presence of urea and a small amount of water. The determining role of water in the solvothermal synthesis is studied. It is found that a small amount of water is crucial for the …
Magnetization Switching of Single Magnetite Nanoparticles …
In this work, we have imaged and studied individual single-domain magnetite nanoparticles 20 nm in diameter by purely optical means. This is an improvement of about 4 orders of magnitude compared to our previous study of single multidomain magnetite nanoparticulate clusters of 400 nm in diameter. The detection sensitivity reaches about 4 × 10 ...
One-Pot Template-Free Synthesis of Monodisperse and Single …
Uniform-sized, monodisperse, and single-crystal magnetite hollow spheres with a diameter of 200−300 nm and a shell thickness of ∼50 nm have been successfully synthesized in high yield using a template-free solvothermal route. The reaction duration and the ethylenediamine amount are shown to play important roles in the formation of the magnetite …
[PDF] Formation of single domain magnetite by green rust …
@article{Miot2014FormationOS, title={Formation of single domain magnetite by green rust oxidation promoted by microbial anaerobic nitrate-dependent iron oxidation}, author={Jennyfer Miot and Jinhua Li and Karim Benzerara and Moulay Tahar Sougrati and Georges Ona-Nguema and Sylvain Bernard and J. -C. Jumas and François Guyot}, journal ...
Non‐Chained, Non‐Interacting, Stable …
Magnetofossils can be characterized quantitatively in bulk samples by magnetic methods. A single magnetofossil chain behaves similarly to a non-interacting stable single-domain (SSD) magnetic grain (e.g., Dunin-Borkowski …
(PDF) The Effect of Stress on Paleomagnetic Signals: A …
pseudo-single-domain magnetite over billion-year timescales. Pr oceedings of the National Academy of Sciences of the United States of Amer - ica, 114 (39), 10356–10360.
Biomimetic Approach for Sustainable Magnetite …
TEM micrographs of magnetite nanoparticles grown in the presence of different polycations for 24 h at pH 11. Corresponding selected area electron diffraction patterns, indexed according to the spinel crystal structure of magnetite are shown, indicating single-crystallinity for all nanoparticles.
Controlled Synthesis and Characterization of Micrometric Single …
A new class of magnetite (Fe 3 O 4) particles, coined as "Single Crystalline Micrometric Iron Oxide Particles" (SCMIOPs), were obtained by hydrothermal synthesis.Both the single Fe 3 O 4 phase content and the particle sizes range, from 1 µm to 30 µm, can be controlled by synthesis. The notable finding states that these particles exhibit vanishing …
Production of Single-Domain Magnetite Throughout Life …
ABSTRACT. Although single-domain particles of biogenic magnetite have been found in different species of pelagic fishes, nothing is known about when it is synthesized, or about whether the time during life when it is produced is correlated with the development of responses to magnetic field stimuli. We have investigated production of biogenic magnetite suitable for use in …
In Vivo Exposure Pathways of Ambient Magnetite …
Here, we report a label-free, machine learning-aided single-particle inductively coupled plasma mass spectrometry (spICP-MS) approach for tracing the exposure pathways of airborne magnetite nanoparticles (MNPs), including external emission sources, and distribution and translocation in vivo using a mouse model. Our results provide quantitative ...
Magnetite Nucleation and Growth | SpringerLink
The authors concluded that Mms6 controls magnetite size to obtain stable single domain particles both in vivo and in vitro. Mms6 C-terminus is hydrophilic and was postulated to accumulate iron ions, thereby triggering crystal nucleation and interacting with the magnetite nanoparticle surface, while the crystal is growing in vivo. ...
Electrical resistance of single-crystal magnetite (Fe3O4) …
The pressure dependence of electrical resistance of single-crystal magnetite (Fe3O4) was measured under quasi-hydrostatic conditions to 100 GPa using low-temperature, megabar diamond-anvil cell techniques in order to gain insight into the anomalous behavior of this material that has been reported over the years in different high-pressure experiments. The …
(PDF) Imaging the Magnetization of Single Magnetite …
This review describes the theoretical basis of PT microscopy, the methodological developments that improved its sensitivity toward single-nanoparticle and single-molecule …
Magnetization Switching of Single Magnetite Nanoparticles …
Single-particle magnetization curves display superparamagnetic to ferromagnetic behaviors, depending on the size, shape, and orientation. Some nanoparticles undergo …
Searching for single domain magnetite in the 'pseudo-single …
Stable remanent magnetization of magnetofossils is carried by single-domain [12, 13] and exceptionally [14] pseudo-single-domain magnetite, which, due to the chemical composition and shape of ...
Hydrostatic pressure effect on magnetic hysteresis parameters …
This paper reports the first in situ magnetic hysteresis measurements of pseudo-single-domain (PSD) magnetite under high pressure up to 1 GPa. The magnetic hysteresis measurements of stoichiometric PSD magnetite samples under hydrostatic pressure were carried out using a piston-cylinder high-pressure cell, and the pressure dependence of the ...
Single-phase magnetite with high saturation magnetization …
Based on obtained results, it was shown that single-phase magnetite can be synthesized using glycine and citric acid only in an inert atmosphere. Deshpande suggested that interactions between ferric nitrate and fuel lead to the formation of magnetite which afterward reacts with atmospheric oxygen and converted to hematite. Ianoş et al. [5 ...
Magnetite: Behavior near the Single-Domain Threshold
Maximum values for the single-domain threshold d0 and superpara-magnetic threshold d8 in pure magnetite are found to be 570 50 and 350 50 angstroms, respectively, which could account for the essentially single- domain character of stable natural remanence in many volcanic and intrusive rocks. Maximum values for the single-domain threshold d0 and superpara-magnetic …
Formation of tabular single-domain magnetite induced by …
A unique form of tabular, single-domain magnetite is produced under nontraditional (low-CO(2)) culture conditions and has a distinct crystal habit and magnetic properties that could be used as a biosignature to recognize ancient biological activities in terrestrial and extraterrestrial environments. Distinct morphological characteristics of …