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Detection, Extraction, and Characterization of Biogenic Magnetite
1985Several difficulties arise when attempts are made to characterize the deposits of magnetite found in metazoans. We are usually forced to deal with very small amounts of material, dispersed in tissues, using indirect methods that are subject to contamination.
Michael M. Walker +3 more
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Carbon Tetrachloride Transformation on the Surface of Nanoscale Biogenic Magnetite Particles
Environmental Science & Technology, 2004Iron-reducing conditions in subsurface environments promote dechlorination reactions via both biotic and abiotic pathways, the latter often mediated via biologically activated minerals formed by dissimilatory iron-reducing bacteria (DIRB). Here we report the major products and pathways associated with the abiotic transformation of carbon tetrachloride (
Michael L, McCormick, Peter, Adriaens
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Biogenic magnetite as a primary remanence carrier in limestone deposits
Physics of the Earth and Planetary Interiors, 1987Abstract Studies on the microbial communities and magnetic phases of samples collected from carbonate oozes at Sugarloaf Key, FL, U.S.A. and calcareous laminated sediments from Laguna Figueroa, Baja California, Mexico have revealed the existence of magnetotactic bacteria and ultrafine-grained single domain magnetite in both environments ...
Shih-Bin R. Chang +2 more
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Biogenic magnetite as an index for Fe availability
Magnetotactic bacteria produce biogenic magnetite in aquatic environments with reduced oxygen (O2) and high Fe concentrations. Increased biogenic magnetite contents in geological archives have been associated with marine deoxygenation, Fe fertilization and productivity.Victor Piedrahita +7 more
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Structural and Morphological Characterization of Biogenic Magnetite Crystals
1991The biological form of the ferrimagnetic mineral, magnetite, was discovered in molluscs (polyplacophora) by Lowenstam (1962). Marine molluscs such as chitons use a specialized tongue or radula, which is in effect a conveyor belt of mineralized teeth, to graze on the algae that adhere to intertidal rocks. Chiton teeth are capped with magnetite, the hard
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Investigation of biogenic magnetite particles by high-resolution electron microscope
Proceedings, annual meeting, Electron Microscopy Society of America, 1984In 1975, Blakemore found aquatic bacteria that swim along earth's magnetic lines of force [1]. They have permanent magnets of iron-rich fine particles within them. Such particles were found by Mössbauer analysis to consist of magnetite in the case of magnetospirilla [2].
T. Matsuda +4 more
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2020
<p>There are longstanding and ongoing controversies about the abiogenic or biogenic origin of magnetite in banded iron formations (BIFs). The trace element composition of magnetite was proposed as a promising tracer for distinguishing biogenic from abiogenic magnetite, which, however, remains to be explored quantitatively.
Xiaohua Han +5 more
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<p>There are longstanding and ongoing controversies about the abiogenic or biogenic origin of magnetite in banded iron formations (BIFs). The trace element composition of magnetite was proposed as a promising tracer for distinguishing biogenic from abiogenic magnetite, which, however, remains to be explored quantitatively.
Xiaohua Han +5 more
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Paleomagnetic evidence for fossil biogenic magnetite in western Crete
Earth and Planetary Science Letters, 1982Abstract Previous paleomagnetic research has shown that the concentration of fine-grained magnetite preserved in Miocene marine clays of western Crete drops during two successive geomagnetic transitions, although the mechanism responsible for this effect was not known.
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Investigation of age-related variations in biogenic magnetite levels in the human hippocampus
Experimental Brain Research, 2002The magnetic properties of human hippocampal tissue from 23 subjects (15 epilepsy patients and eight cadavers with no neuropathology) were analysed and tissue concentrations of magnetic material were calculated. The biogenic iron oxide magnetite (Fe(3)O(4)) is the dominant source of magnetisation in the tissue. Analysis of the group as a whole revealed
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Avian Navigation, Geomagnetic Field Sensitivity, and Biogenic Magnetite
1985How birds manage to find their way around in the world has long been a source of fascination. These animals range widely when foraging for food, sometimes traveling 100 km or more from their nest or roost. Moreover, many species of birds fly long distances between breeding grounds and wintering areas, returning with extraordinary precision to specific ...
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