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Showing 1 to 8 of 8 for “"Vivianite"”.
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Kinetics of the release and precipitation of phosphorus in anaerobic digesters sequencing biological phosphorus removal systems
… like struvite, calcium-phosphorus compounds and vivianite (Fe₃(PO₄)₂). The formation of vivianite is limited by the competitive precipitation of siderite (FeCO₃ ). The extent to which the compounds are precipitated depends on the solids retention times, ionic strengths, size and amorphous nature …
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Iron reduction mediated increases in carbon oxidation and phosphorus precipitation in on-site wastewater systems
… and precipitate phosphorus with reduced iron as vivianite. We used carbon-14 radiolabeled acetate, lactate, propionate, butyrate, glucose, starch, xylose and oleic acid to demonstrate that short and long term carbon oxidation is increased when different forms of Fe3+ are amended to septic …
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Geochemcial Controls on Arsenic and Phosphorus in Natural and Engineered Systems
… was slowly reversed as orpiment (As2S3) and vivianite [Fe3(PO4)2] slowly precipitated, but under other circumstances, these solids would not be expected to form. Modeling results suggest that arsenic and phosphate concentrations could either increase or decrease in response to reaction …
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Characteristics and conditioning of anaerobically digested sludge from a biological phosphorus removal plant
… including hydroxyapatite, struvite, and vivianite. Calcium phosphorus precipitates were the most prevalent in both sludges, but the percentage of magnesium phosphorus precipitates increased with the onset of BPR. Cationic organic polymer conditioning dosages needed to achieve acceptable …
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The Influence of Water Chemistry on H2 Production and Uptake during Anaerobic Iron Corrosion
… of PO43- formed a protective film, possibly vivianite Fe3(PO4)2, on the iron surface that eventually stopped H2 release. However, results were consistent with the idea that corrosion is an irreversible process that is relatively insensitive to low level H2 (<1 atm). Possible alternative …
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Sedimentology and diagenesis of Ediacaran phosphorites from South China
… stabilization of ferrous iron-phosphates (e.g., vivianite), this cement is suggestive of precipitation from ferruginous porewaters. This is the first direct evidence for iron-phosphate minerals in Ediacaran phosphorites and substantiates previous hypotheses of P burial beyond primary calcium …
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Stratigraphic setting of some new and rare phosphate minerals in the Yukon Territory
… satterlyite, maricite (NaFePO₄), vivianite-baricite ((Fe,Mg) ₃(PO₄)₂·8H₂0), varulite ((Na,Ca)(Mn,Fe)₂(PO₄), and their alteration products. Nahpoite (Na₂HPO₄), a new mineral which occurs as a white powdery alteration product of maricite in some nodules at Big Fish River, was …
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Les iguanodons de Bernissart: leur évolution diagénétique et les processus de dégradation
… apatite, calcium sulfate and to a lesser extent vivianite). Pyrite is the most abundant authigenic mineral in the Iguanodon fossil bones. It occurs in different morphologies (crystals, framboids, sticks, fibroradial structure, thin coating…). Four kind of pyrite were determined according to the …