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Showing 1 to 20 of 28 for “"Mineral precipitation"”.
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The effect of calcium and magnesium on carbonate mineral precipitation during reactive transport in a model subsurface pore structure
Carbonate mineral precipitation in the subsurface at the interface of two advecting fluids can result in physical and chemical changes in the pore network. This can affect the effectiveness of various applications including carbon sequestration and in situ remediation. In this work we evaluate the …
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Reconstructing local redox conditions, mineral precipitation processes and nutrient availability in seawater during deposition of the Transvaal Supergroup, South Africa
… oceans influenced iron redox states and primary mineral precipitation, affecting the cycling of other trace elements and nutrients. While carbonate minerals are commonly used as geochemical archives, reconstructions using IF have proved more challenging, with many studies analysing bulk powders. …
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The use of a calibrated three phase (solid-aqueous-gas) plant-wide wastewater treatment model to simulate data on mineral precipitation
The mass manufacture of novel chemicals, extensive use, and the release of micropollutants into the environment are inevitable occurrences in contemporary society. In reality, wastewater treatment plants are the primary means of spreading micropollutants, primarily because of their inadequate …
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Oxygen and hydrogen isotopic analysis of tourmaline by secondary ion mass spectrometry
The O and H isotopic composition of minerals can provide valuable information on the source of the fluids and temperature of mineral precipitation. To obtain accurate isotopic measurements using SIMS, it is important to select chemically similar standards and samples to correct for both matrix …
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The geochemical evolution of saline groundwater within a fresh water aquifer south of Oakes, North Dakota
… mechanism within the center of the depression. Mineral precipitation occurs at the water table in surficial clays just below land surface. Major recharge events dissolve the precipitated minerals, move the saline water down to the water table, and-then by miscible displacement, transport the …
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An investigation into the characteristics and sources of light emission at deep-sea hydrothermal vents
… to mixing with ambient seawater (2°C) leading to mineral precipitation. Data from these types of vents show the existence of non-thermal, temporally varying light in the 400-700 nm region. This light is probably caused by mechanisms related to mixing and precipitation, such as chemiluminescence, …
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An investigation into the characteristics and sources of light emission at deep-sea hydrothermal vents
… to mixing with ambient seawater (2°C) leading to mineral precipitation. Data from these types of vents show the existence of non-thermal, temporally varying light in the 400-700 nm region. This light is probably caused by mechanisms related to mixing and precipitation, such as chemiluminescence, …
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Mineral, fluid and thermal evolution in veins from late orogenic coal basins of the Cantabrian Zone (Variscan, NW Spain)
The detailed study of syn-tectonic mineral veins and textural features of fluid inclusions is a useful approach for reconstructing the fluid and thermal evolution in diagenetic and very low-grade metamorphism environments. Here, mineralised fissures within the clastic sedimentary rocks of the …
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Marine carbohydrate-active enzymes illuminate microbial ecology, evolution, and carbonate precipitation
… structure these ancient ecosystems and control mineral formation via the alkalinity engine and organic surfaces involved in mineral nucleation and growth. Marine microbialites—mineralized microbial mats—preserve the earliest unequivocal evidence of life on Earth and billions of years of the …
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Microbial Communities Associated with Phosphoclast-bearing Sediments of the Benguela Upwelling Zone
… of many biological molecules. Calcium phosphate mineral deposits, known as phosphorites, are also the primary source of P for agriculture. Understanding phosphorite formation may improve management of P resources. However, the processes that mediate calcium phosphate mineral precipitation in …
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Approximating three-dimensional fluid flow in a microfluidic device with a two-dimensional, depth-averaged lattice Boltzmann method
… biodegradation and biofilm growth, and mineral precipitation coupled to fluid flow in MFDs that are shallow rectangular channels with regular or irregular interior pore structure. The success of these reactive transport models is dependent on accurate determination of the velocity field, …
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Basalt alteration and its consequences
… chemical environments that can drive carbonate mineral precipitation and other secondary mineral formation. The extreme reactivity of basalt, with very fast weathering rates relative to other surface rocks, means that there is great interest in understanding the impact of basalt alteration on …
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Formation of authigenic minerals during microbial degradation in artificial marine media
… iron influence the development of authigenic minerals? 3) How do microbial metabolisms affect dissolved iron concentrations and authigenic mineral precipitation? My experimental system consisted of dead cyanobacterial cells that were mixed with acid-washed glass beads, thereby making an …
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Characterising subaerial basaltic ‘a‘ā lava flows as potential geothermal reservoirs: Nordeste volcanic complex, Volcanic, São Miguel, Azores
… the sealing of vesicle and fluid networks due to mineral precipitation, although the alteration can also lead to mineral dissolution. Additionally, any secondary tectonic fracturing can form critical areas of high permeability and fluid pathways. <br/><br/>Since the porosity and permeability of …
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Geomechanical impact of bio-competitive exclusion chemical on reservoir rocks.
… saturation test, the results showed there was mineral dissolution and precipitation response, which caused the separation of grain particles, and as a result, decreased the strength of the rock. The core flooding investigation was performed at increasing concentrations of 637.5 ppm, 850 ppm, …
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Characterizing the mechanism and rate of calcium phosphate precipitation in aerobic granular sludge
… removal while enhancing recovery through the precipitation of calcium phosphate minerals within the granule1–3. A rigorous understanding of precipitation mechanism and rate has been limited by simultaneous biological uptake and release of phosphate and cations. As a result, more work is needed …
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Design, Fabrication, and Characterization of Three Dimensional Complete Scaffolds for Bone Tissue Engineering
… gelatin/PLLA blends as means to increase overall mineral precipitation and distribution throughout the scaffolds when incubated in concentrated simulated body fluid (SBF)10XSBF. Mixture of 10% gelatin and PLLA resulted in the significantly higher degree of mineralization, increased mechanical …
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Quantifying polyphosphate energy for modelling of polyphosphate accumulating organisms behaviour in anaerobic digestors
… particularly regarding pH predictions and mineral precipitation patterns. The research employed a University of Cape Town membrane bioreactor activated sludge (UCT MBR AS) system to cultivate an enriched PAO culture. This approach successfully achieved high PAO concentrations, enabling …
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Geochemical modeling-based prediction of water-rock interaction during aquifer storage and recovery utilizing selected Colorado Front Range aquifers
… elements from bulk rock geochemical analysis and mineral identification from petrography are used to infer a generalized mineral suite to represent each of the formations of interest. Similarly, compositional analyses from domestic water well samples, including major anions and cations and …
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Understanding ureolytic calcium carbonate biomineralization for crack repair in cementitious materials
… and open pathways for corrosive chemicals. Biomineralizaion is a common phenomenon in which most bacteria can produce precipitates that can be utilized to block the pathways and heal the cracks eventually. Researchers have developed different ways to apply bacteria on the outside of cracked …
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