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Showing 1 to 9 of 9 for “"Iron oxyhydroxides"”.
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Understanding Formation and Transport of Amorphous Iron Oxyhydroxides in Porous Media using Microfluidic Flow Cells- a Novel Method to Study Freshwater Iron Cycling
… which in turn has deep impact on the iron cycling and thus the fate of contaminants in the water column. We constructed an experimental micromodel that to observe key processes that affect biogeochemical iron cycling in the fresh water interface zones where the oxic surface water mixes …
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Fossil preservation and the effects of groundwater leaching on fossils in the Yorktown Formation (Upper Pliocene), Virginia
… possibly caused precipitation of fine-grained iron oxyhydroxides. All carbonate material in the vicinity of the paleochannel is completely dissolved away, although iron oxyhydroxide coatings of fossils remain. Away from the paleochannel Crepidula fornicata (gastropod; aragonite), Ostrea sp. …
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Mechanisms of metal release from contaminated coastal sediments
… these metals. The trace metals are scavenged by iron oxyhydroxides and released to the porewaters when these oxides are reduced. At the strongly reducing site in Boston Harbor, there is seasonal transfer of trace metals from oxide phases in winter, to sulfides phase in summer. At the …
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Kinetics of Arsenopyrite Oxidative Dissolution by Oxygen
… at 25°C and circumneutral pH. Release rates for iron, arsenic and sulfur are calculated for a variety of initial dissolved oxygen (DO) concentrations. Results indicate that the rate of arsenopyrite oxidation, represented by the rate law r = A(6.76 x 10-11) where the rate, r, is in mol/s and …
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Mechanisms of metal release from contaminated coastal sediments
… these metals. The trace metals are scavenged by iron oxyhydroxides and released to the porewaters when these oxides are reduced. At the strongly reducing site in Boston Harbor, there is seasonal transfer of trace metals from oxide phases in winter, to sulfides phase in summer. At the …
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Arsenic Stability In Fresh and Aged Amorphous Ferric Hydroxide Sludges Generated from Brine Treatment Processes
Using Environmental Protection Agency occurrence and concentration data, it is estimated that about 6 million pounds of arsenic-bearing residuals (ABSR) will be generated annually in the United States when full compliance with the new standard for arsenic in drinking water (10 μg/L) is realized. …
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Templating of Metal Oxide and Oxhydroxides Nanoparticles in Surfactant Media
… of akaganéite ffl-FeOOH) and goethite ((X-FeOOH) iron oxyhydroxides with nanometre particle size and acicular morphology was targeted. Both P & a-FeOOH particles were generated via forced hydrolysis of Fe" ions in acidic media. Templated syntheses of these particles were carried out in surfactant …
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Adsorption–Desorption Reactions in the Weathering Zone: Implications for Silicate Weathering & the Carbon Cycle
… adsorbed phase. These experiments utilised environmentally relevant adsorbent minerals and surface waters. By systematically varying the mineral-to-water ratio, reaction duration, and water chemistry, the experiments aimed to elucidate the role of adsorption-desorption reactions in controlling …
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Rare metal resources in polymetallic nodules from the Eastern Equatorial Pacific Ocean
The Clarion-Clipperton fracture zone (CCFZ) in the eastern equatorial Pacific is the area with the greatest interest in terms of metal resources in polymetallic nodules. The nodules are enriched (relative to crustal composition) in economically important metals such as Mn, Ni, Cu, Zn, and so-called …