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Showing 1 to 16 of 16 for “"sequential extractions"”.
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Investigation of Lead Hydrolytic Polymerization and Interactions with Organic Ligands in the Soil/Sediment-Water Environment
… the contaminated soil by polar organic solvents. Sequential extractions show that 16.6±1.4 % of the Pb is organically complexed. Complexation of Pb with fulvic acid provided new information on the extent of Pb association with soluble organic matter. The overall results of this research have …
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Evaluation of Metal Concentration in Water and Soil in the Southern Region of Lake Nacogdoches
… mobility of the element. A modified Tessier soil sequential extraction procedure was used to determine the speciation of metals in soil samples. Thus, elements in soils are present in various physicochemical forms, which in turn influences its bioavailability. In this study, soil samples were …
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Sediment chemistry as an archive of provenance and weathering in the Mekong River Basin
… the residues after leaching and a suite of sequential extractions 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 …
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Monitoring of atmospheric polycyclic aromatic hydrocarbons through optimization of analytical techniques
… such as choice of extraction solvent, number of sequential extractions and PDMS trap orientation were investigated and optimized. The proposed method used minimum solvent (total 2 mL hexane) and was quicker (approximately 4 min needed for PASE extraction including weighing, compared to the 11.5 …
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Transport and adsorption-desorption of heavy metals in different soils
… Sn in alkaline and acidic soils. Furthermore, sequential extractions were accomplished to examine their behavior in soils. Also, the competitive reactivity of Sn and Pb in two acidic soils was quantified. Additionally, the effect of introducing Cd and Cu after a Pb pulse in calcareous soil was …
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Characterization and remediation of toxic metals in wastewater reuse for agricultural irrigation
… This research utilizes Tessier’s method of sequential extractions to inventory metals in different chemical pools (Tessier et al., 1979). A field of inexpensive and widely available sorbents, including sugarcane bagasse, ground rice husk, and sawdust, is compared against the conventional …
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Characterization and prediction of long-term arsenic mobility, dissolution, and kinetic behavior in arsenic contaminated floodplain deposits of Whitewood Creek and the Belle Fourche River, South Dakota
… of arsenic and other geochemical constituents. Sequential extractions of the sediments were performed to determine the mineralogical setting of the arsenic as well as the proportion of arsenic available at different rates of release into the environment. Additionally, various historical data …
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The Chemical Forms and Plant Availability of Copper in Composting Organic Wastes
A seven-step sequential extraction scheme was used to track changes in operationally defined copper speciation during the composting of a mixture of grass clippings and sawdust originating from tanalised timber. Starting materials were either unamended or treated with differing amounts of soluble …
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Dissolution, Transport, and Fate of Lead on Shooting Ranges
… site. This soluble lead is captured by the soil. Sequential chemical extractions revealed that vertical lead migration beyond the A-horizon was minimal. The bound-to-Fe & Mn oxides and bound-to-carbonates soil fractions were identified as significant reservoirs for sequestration of lead in the …
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Sorption of lead and arsenic on soil components and effectiveness of phosphates for remediating lead and arsenic contaminated soils
… exceeding other chemically stabilized forms. Sequential extractions of Pb have been used to determine the suitability of phosphates to immobilize Pb. Laboratory studies were conducted to investigate whether the lead pyromorphite formation is the artifact of the sequential extraction or it is …
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Non-traditional sources of critical minerals from the Western Canada Sedimentary Basin
… machine learning study. Leaching experiments and sequential extractions indicated that REE in the Ca-rich Poplar River ashes were most easily leached into solution, while XAS analyses found the REE were hosted in silicate and phosphate mineral phases that were transferred from the coals to the …
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Photochemistry of single-walled carbon nanotubes in the aquatic environment, and their extraction from soils
… efficiency of more than 90% after four sequential extractions. To purify the SWCNTs from the co-extracted humic material, density gradient ultracentrifugation (DGU) was tested using two different commercially available unfunctionalized SWCNTs.</p>
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Changes in water chemistry and fluvial geomorphology from arsenic contaminated floodplains of Whitewood Creek and Belle Fourche River, South Dakota
… arsenic in the mine tailings. Her work involved sequential extractions of the tailings to determine the mineralogical setting of the arsenic and its rate of release. She also used statistical regression on historical data to estimate the physical and chemical removal of arsenic from Whitewood …
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Untersuchungsergebnisse zur Mobilität und Remobilisierung von Kupfer und Antimon in wasserwirtschaftlich relevanten, porösen Lockergesteinen durch Säulenversuche und mit reaktiver Transportmodellierung
… to support mobility data of copper and antimony sequential extractions of column beds were performed after the column experiments. As an essential result, it emerged that copper is accumulated increasingly in areas near the surface, while antimony is distributed in the whole profile. Therefore, …
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Sorption of Metals onto Natural Sediments and Engineered Iron Oxide Nanoparticles
… of phosphate addition to the influent fluid. Sequential extractions and laser-induced fluorescence spectroscopy (LIFS) of column sediments suggested that the retained U(VI) was primarily in adsorbed forms. These results indicate that in-situ remediation of groundwater by phosphate addition …
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Biogeoquímica del fósforo en el suelo: optimización de criterios para un uso agronómico eficiente y ambientalmente aceptable de un recurso no renovable
… citrate + 0.11 M NaHCO3 (CB), (iv) the two first sequential extractions in the Ruíz et al. (1997) fractionation scheme (NaOH +CB), (v) extraction with anion exchange resins (AER) in Cl- and HCO- 3 forms. Total available P (TAP) values in soils were obtained by P depletion experiment by growing …