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Showing 1 to 16 of 16 for “"jarosite"”.
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Jarosite AFe3(SO4)2(OH)6: Kristallchemische Charakterisierung und aquatische Reaktionen
… Umwelt. Unter diesen sauren Bedingungen werden Jarosite (AFe3(SO4)2(OH)6) gebildet, die Schadstoffe binden aber unter veränderten pH-, Eh-Bedingungen wieder freisetzen können. Synthesen lieferten Kristalle bis 100 um Kantenlänge. Ihre Morphologie ist von (001) und (012)-Flächen dominiert. Die …
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Biosignature storage in sulfate minerals- synthetic and natural investigations of the jarosite group minerals
The discovery of jarosite on Mars in 2004 generated increased interest in the properties of the mineral related to the search for life on other planets. Several studies indicate that the formation of jarosite can be linked to biological activity on Earth and biomolecules such as amino acids have …
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Biosignature storage in sulfate minerals- synthetic and natural investigations of the jarosite group minerals
The discovery of jarosite on Mars in 2004 generated increased interest in the properties of the mineral related to the search for life on other planets. Several studies indicate that the formation of jarosite can be linked to biological activity on Earth and biomolecules such as amino acids have …
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Study of spatiotemporal changes within the abandoned flotation plant site of Kirki (NE Greece) via clustering on Sentinel-2 data
… (from the USGS Spectral Library) — including jarosite species (K-, Na-, H₃O-jarosite), goethite, hematite, gypsum, butlerite, and lead-bearing phases (cerussite, anglesite, hydrocerussite, pb-jarosite, beaverite) — using Pearson correlation as the primary similarity metric. The temporal …
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The mobility of metals in acid mine drainage from abandoned coal mines
… Associated precipitates consisted primarily of jarosite with minor amounts of goethite, lepidocrocite, ferrihydrite and gypsum, with ferrihydrite being the major component of only one precipitate sample. The presence of algae at one of the sampling sites appeared to act as a template for the …
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Concretions and nodules in the Hell Creek Formation, southwestern North Dakota
… rounded masses; coprolite-cored masses; jarosite bodies; pyrite spheres; baritic sandstone lenses; and cone-in-cone masses. The nodular types include siderite masses and lenses and iron oxide spheres. Moving groundwater solutions, in many cases acccmpanied by locally reducing conditions …
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An investigation into the ferric leaching of chalcopyrite : a sub-process in the bioleaching of chalcopyrite
… of passivation include either the formation of jarosite, ferric hyroxy sulfate, sulfur or iron deficient polysulfide like covellite (Klauber et al. , 2001 , Parker et al., 1981 , Munoz et al, 1976, Warren et al., 1985 and Parker et al., 1981). Recent research has suggested that different …
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Influence of pH, phosphorus addition and soil water content on phosphorus pools in acid sulfate soils
… of P were determined in incubated soils and jarosite, separately. The maximum sorption capacity of the soil was 350 mg P kg-1. Jarosite had a high capacity to bind P and contributed about 50% to P binding in this soil. Labile P represented more than 50% of added P at P rates above 350 mg P …
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Resolving the Structure, Morphology, and Trace Metal Association of Nanominerals: The Case for Schwertmannite
… agree well with d-spacings of goethite (and jarosite in natural samples) implying that the transformation from schwertmannite to these phases occurs as a gradual structural reordering at the nanoscale. In the synthetic study, the complete transformation from schwertmannite to goethite …
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Investigating the Transformations of Arsenic and Toxic Metal(Loid)S Speciation and the Impact on Arsenic Bioaccessibility in Particulate Matter from Mine Tailings Sites Distributed in Different Climates
… mineralogy—particularly Fe-bearing phases like jarosite and ferrihydrite—playing a critical role. Pb exhibited low bioaccessibility due to transformation into stable phases (e.g., plumbojarosite), while Zn and Cd were more labile, especially under acidic conditions. Climatic conditions strongly …
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Investigation of Chalcopyrite Leaching Kinetics by Alternative Leaching Chemicals
… supported the reaction mechanism as K-jarosite precipitation on a leached residue from MSA – Cr2O72- system, which hindered mass transport and passivated chalcopyrite. Overall, nitrate leaching could be the more effective, economical and compatible than other alternative oxidants for …
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Fluids in Planetary Systems
… formed. The results of this study indicate that jarosite is likely to form as a result of water-limited chemical weathering of basalts. Magnesium sulfates are only predicted to form as a result of evaporation. This suggests that in order to form the alteration assemblages recently observed by the …
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The Semliki Basin, Uganda : its sedimentation history and stratigraphy in relation to petroleum accumulation
… Authigenic minerals such as anatase and jarosite and secondary precipitates such as calcite and gypsum have also been interpreted as oxidation products of sulphides in the sediments. The study has allowed a better understanding of the stratigraphic relationship of the different rock units …
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Evaluation of environmental materials as thermal witness materials
… profile. The thermosensors under investigation, Jarosite and silicate glass are materials that are ubiquitous in both urban and rural environments. Jarosites undergo decomposition losing (OH) and SO_3 upon thermal exposure. The decomposition mechanism is complex and is governed by a set of serial …
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A mineralogical study of the Harmon lignite bed, Bullion Creek Formation (Paleocene), Bowman County, North Dakota
… pyrite, gypsum, barite, celestite, siderite, and jarosite were probably epigenetic products which formed after seam compaction and coalification. The present mineral content of the Harmon lignite is probably the result of the characteristics of the depositional environment. Authigenic processes …
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Stratigraphy and paleontology of the upper Cretaceous Morden Member (Vermilion River Formation) in the outcrop area, northeastern North Dakota
… feldspars. Secondary minerals include gypsum, jarosite, pyrite, calcite, and minor carbonates and sulfides. X-ray analysis of six samples from a single measured section suggests the mineralogy to be essentially uniform throughout the vertical extent of the Morden Member.</p> <p>Thirty-six …