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Showing 1 to 20 of 38 for “"oxyhydroxide"”.
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The synthesis of aluminium hydroxide and oxyhydroxide
… aluminium hydroxide ( Al(OH)₃ ) and aluminium oxyhydroxide (AIOOH) polymorphs. The particular oxygen sublattice of the starting material is critical in determining which phases of beta alumina are formed. Boehmite and bayerite are known to yield pure β"-alumina. In this investigation, the …
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Effect of aluminum oxyhydroxide coatings on the performance of limestone drains
… can be reduced by aluminum (Al) and iron (Fe) oxyhydroxide coatings that form on the limestone, because the coatings inhibit the transport, and thus neutralization, of hydrogen ions (H+) derived from acid mine drainage. I used mixed flow reactor experiments to investigate the effect of Al …
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Linking morphology and reactivity: growth and ligand-assisted dissolution of cobalt oxyhydroxide.
Reactions at the interface of solid materials have a significant role in many fields of study, ranging from environmental science to industrial manufacturing. Identifying and quantifying the reactive surface area of these materials is vital to understanding the reactions in which they participate. …
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The Effect of Clay Content and Iron Oxyhydroxide Coatings on the Dielectric Properties of Quartz Sand
… quartz sand/kaolin clay mixtures and ferric oxyhydroxide coated quartz sand. Results from the experiments show that the dielectric responses of quartz-clay and iron oxyhydroxide modified samples are not significantly different from the pure quartz Control. Increasing clay content in quartz …
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Competitive sorption of phytic acid and phosphate in agricultural soils and at the amorphous aluminum oxyhydroxide-water interface
Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2024-05-01
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The Low Temperature Surface Geochemistry And Kinetics Of Pyrrhotite Weathering: Influences On Acid Mine Drainage (amd)
… zoned. The outermost surface layer is Fe(III)-oxyhydroxide, below which exists an Fe-deficient, S-rich layer that displays a continuous, gradual decrease in S/Fe until that of the unaltered pyrrhotite. Compositional zones develop by electron and iron migration along a sequence of metal …
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An integrated approach for the mitigation of acid rock drainage (ARD) associated with pyrrhotite in nickel deposits
… observed the formation of a hydrophilic ferric oxyhydroxide layer which enables depression of pyrrhotite during flotation. This layer has been reported in literature to inhibit the further oxidation of the pyrrhotite surface. Thus passivation can also take advantage of the formation of the …
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Transition Metal Heterogeneous Catalysis Towards Applications in Sustainable Energy: Leveraging Rational Design Principles for Activity, Stability, and Stereoselectivity
… to phase transformations from MHOF to the Ni oxyhydroxide-like phase during OER, providing insight into the phase stability of these types of materials in base. During extended electrochemical OER cycling, linkers leach from the MHOF structure, exposing more electrochemically active Ni sites, …
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Effect of Coatings on Mineral Reaction Rates in Acid Mine Drainage
… project investigated the conditions where iron oxyhydroxide coatings form on oxidizing pyrite and the potential strategies to prevent "runaway" AMD by reducing the rate of acid production to the point that the acid can be neutralized by the surrounding rocks. In both studies, experiments were …
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Sediment chemistry as an archive of provenance and weathering in the Mekong River Basin
… targeting the exchangeable cation pool and Fe-Mn oxyhydroxide pool. In conjunction with the river sediments, new data on major elements and lithium isotopes in the dissolved load and from a sediment core of Tonle Sap, a lake connected to the Mekong, are also presented for comparison. The major …
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Thermal and Diagenetic Evolution of Carboniferous Sandstones, Central Appalachian Basin
… The distribution of siderite and iron-oxide/oxyhydroxide may reflect the second order paleoclimatic signature recognized throughout the Carboniferous, where siderite formed during everwet periods and iron-oxide/oxyhydroxide during semi-arid conditions, reflecting differences in redox. Second, …
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Proton-coupled electron transfer in molecular and material catalysis
… electrocatalysts, and iron-doped nickel-oxyhydroxide thin films used for oxygen evolution reaction, are explored by means of quantum chemistry. Detailed electronic structural analysis performed using density functional theory is used to provide atomic level understanding of these …
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Characterization of the Genes Involved in Biosynthesis and Transport of Schizokinen, a Siderophore Produced by <em>Rhizobium leguminosarum</em> IARI 917.
… aerobic conditions iron forms insoluble ferric oxyhydroxide polymers. Siderophores are low molecular weight compounds that scavenge ferric ions, bind with high affinity, and transport it into the cell via multicomponent transport systems. <em>Rhizobia</em> are soil dwelling organisms that form …
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Molecular Mechanism of Ferricsiderophore Transport via the Outer Membrane Receptor FhuA in <em>Escherichia coli</em>.
… abundant, iron exists mostly as insoluble iron-oxyhydroxide. Bacteria secrete siderophores to chelate iron and transport it into the cell via specific outer membrane receptors. The FhuA receptor protein transports ferrichrome, a siderophore produced by <em>Ustilago sphaerogena</em>. We …
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Effects of phytic acid sorption on iron polymerization and at the ferrihydrite-water interface
… a new role of phytic acid in the formation of Fe oxyhydroxide minerals.
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The effects of bicarbonate and mineral surfaces on uranium immobilization under anaerobic conditions
… presence and absence of Fe-Gel (amorphous ferric oxyhydroxide) and gamma-Al2O3. In the presence of a HEPES buffer at pH 8, results demonstrate direct homogeneous reduction in several hours in the absence of Fe-Gel or gamma-Al2O3, and reduction within a 48-hour period in the presence Fe-Gel or …
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Scavenging of particulate and dissolved lead compounds by coprecipitation with manganese oxyhydroxides
… of heavy metals. During precipitation, Mn oxyhydroxides scavenge many heavy metals, including Pb, in a variety of natural environments. Because of this phenomenon, the precipitation of Mn oxyhydroxides may provide a remediation technique for removing Pb from contaminated aqueous solutions. …
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The Distribution of Dissolved Barium Along the U.S. Geotraces North Atlantic Transect: Impact of Biogeochemical Processes, Circulation and Phase Association
… during adsorption of dissolved barium to ferric oxyhydroxide through an increase in pH. There was evidence of a hydrothermal Ba input from the Mid-Atlantic Ridge and a near surface maximum along the continental slope of North America from a submarine groundwater discharge. Lastly, the error in …
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Jarosite AFe3(SO4)2(OH)6: Kristallchemische Charakterisierung und aquatische Reaktionen
… in Lösung geht. Als Produkte treten Eisen(III)-Oxyhydroxide auf, die als Goethit identifiziert wurden. Sie können, wie im Fall des Cr(III)-haltigen Jarosits, als Senke für im Jarosit enthaltene Schadstoffe wirken. Von wesentlicher Bedeutung für die aquatischen Reaktionen ist die Struktur der …
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