Results 161 to 170 of about 2,338 (195)

Biogenic magnetite and the magnetization of sediments

Journal of Geophysical Research: Solid Earth, 1990
Biogenic magnetites are produced through the reduction of ferric iron by both biologically induced (extracellular) and biologically controlled (intracellular) processes. With few exceptions, all are ultra‐fine‐grained, single‐domain magnetite. Biogenic magnetites formed by magnetotactic bacteria (biologically controlled) have been shown to contribute ...
Lovley, Derek, Stolz, John F, Haggerty, Stephen E   +2 more
openaire   +1 more source

Biogenic magnetite, detrital hematite, and relative paleointensity in Quaternary sediments from the Southwest Iberian Margin

Earth and Planetary Science Letters, 2013
Magnetic properties of late Quaternary sediments on the SW Iberian Margin are dominated by bacterial magnetite, observed by transmission electron microscopy (TEM), with contributions from detrital titanomagnetite and hematite. Reactive hematite, together
J E T Channell, D A Hodell, V Margari
exaly   +3 more sources

Biogenic magnetite nanoparticles for the magnetic separation of microalgae

Algal Research
Igor Taveira, Tarcisio Correa, Fernanda Abreu   +2 more
exaly   +2 more sources

Morphology and structure of biogenic magnetite particles

Nature, 1983
Blakemore1 found aquatic bacteria that swim along magnetic lines of force. Such bacteria have small particles of magnetite (magnetosomes) within them2,3 of various shapes3–5. We describe here the morphology and structure of bacterial magnetosomes investigated by high-resolution electron microscopy.
Tsuyoshi Matsuda, Junji Endo, Nobuyuki Osakabe, Akira Tonomura, Tatsuo Arii   +4 more
openaire   +1 more source

Biogenic magnetite as a basis for magnetic field detection in animals

Biosystems, 1981
Bacteria, sharks, honey bees, and homing pigeons as well as other organisms seem to detect the direction of the earth's magnetic field. Indirect but reproducible evidence suggests that the bees and birds can also respond to very minute changes in its intensity. The mechanisms behind this sensitivity are not known.
J L, Kirschvink, J L, Gould
openaire   +2 more sources

Impact of Biogenic Magnetite Formation and Transformation on Biogeochemical Cycles

Elements, 2023
Magnetite is a redox-active mineral that can form from both abiotic and biotic processes, and plays an active role in different biogeochemical cycles. Biogenic magnetite particles have properties that differ from their abiogenic counterparts in a variety of ways, including their size, chemical purity, magnetic properties, and association with biomass ...
Andreas Kappler, Aaron Thompson, Muammar Mansor   +2 more
openaire   +2 more sources

Microstructure and Properties of Biogenic Hydroxyapatite Doped with Magnetite

Advances in Science and Technology, 2006
In this study the hydroxyapatite powder was sintered together with magnetite nanopowder, which due to its low reactivity is commonly used in medicine, eg. in magnetic resonance. Two types of sintered materials, containing equal content 6 mol% of biogenic hydroxyapatite (BGHAp), reinforced with 50 wt% of different glass phases, were tested.
Magdalena Szutkowska, Marcin Leonowicz, L.A. Ivanchenko   +2 more
openaire   +1 more source

Ferromagnetic resonance and low-temperature magnetic tests for biogenic magnetite [PDF]

Earth and Planetary Science Letters, 2004
Magnetite is both a common inorganic rock-forming mineral and a biogenic product formed by a diversity of organisms. Magnetotactic bacteria produce intracellular magnetites of high purity and crystallinity (magnetosomes) arranged in linear chains of ...
Benjamin P Weiss, Joseph L Kirschvink, Robert E Kopp   +2 more
exaly   +1 more source

Synthetic analogues of biogenic magnetite: synthesis and characterization of magnetite nanoparticles

Materialwissenschaft und Werkstofftechnik, 2011
AbstractBiogenic magnetite serve for a wide range of biological functions, including the orientation of animals in the space and also play an important role in the brain functioning. We describe the synthesis and characterization of magnetite nanoparticles that are the synthetic analogues of biogenic magnetite. Magnetite nanoparticles were prepared via
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Magnetic properties of single biogenic magnetite nanoparticles

Journal of Nanoparticle Research, 2011
Biogenic magnetite nanoparticles (MNP) extracted from the magnetotactic bacterium Magnetospirillum gryphiswaldense MSR-1 have been systematically studied by atomic force microscopy (AFM) and magnetic force microscopy (MFM). Isolated single MNP and chains of MNP were obtained from diluted MNP aqueous suspension dried on mica surfaces in a homogeneous in-
J. D. Wei, I. Knittel, C. Lang, D. Schüler, U. Hartmann   +4 more
openaire   +1 more source