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Showing 1 to 20 of 23 for “"Ferric ions"”.
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Enhanced Mineralization of Phenol and other Hydroxylated Compounds in a Photocatalytic Process assisted with Ferric Ions
… contaminated wastestreams. Photocatalytic reactions take place at a slow rate nonetheless. Efforts have focused on the improvement of photocatalytic reactors design and on the enhancement of the photocatalyst activity through various doping techniques. There have been some important …
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A Potentlometrie Study of Formal Redox Potentlals in the Zimmermann-Reinhardt Determination of Iron in an Ore
… the formal redox potential of the ferrous-ferric system at the end point of the Zimmerrnann-Reinhardt method of determining iron in an ore. | The potential is lowered somewhat more than the theoretical value because the activities of the ferrous and ferric ions are considerably affected by …
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An Absorbed Dose to Water Primary Standard for Ir-192 Brachytherapy
… The radiation chemical yield (G-value) of the Ferric ions in the Fricke solution was measured at Co-60 and 250 kVp X-ray, yielding 1.610 ± 0.010 μmol J-1 and 1.602 ± 0.009 μmol J-1 respectively. A log-linear interpolation was conducted based on the two standard beam values to realize the …
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Characterization of the Genes Involved in Biosynthesis and Transport of Schizokinen, a Siderophore Produced by <em>Rhizobium leguminosarum</em> IARI 917.
… however, at physiological pH and aerobic conditions iron forms insoluble ferric oxyhydroxide polymers. Siderophores are low molecular weight compounds that scavenge ferric ions, bind with high affinity, and transport it into the cell via multicomponent transport systems. <em>Rhizobia</em> are …
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Bonding Characteristics and Devitrification Behavior in Iron-Containing Sodium-Silicate Glasses
… of thermally induced structural transformations in the Na(,2)O.2SiO(,2) (,1-x)(.) Fe(,2)O(,3) (,x) glass system with x (LESSTHEQ) 0.3 have been carried out by means of a variety of techniques including XRD, AES, SIMS, EXAFS, and Mossbauer effect spectroscopies. On the basis of the XRD …
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Enhance heme biosynthesis in Saccharomyces cerevisiae
… of ALE and ARTP to induce beneficial mutations for augmented heme biosynthesis, the results highlighted the difficulties in modifying metabolic pathways for intended enhancements. Additionally, the supplementation of ferric ions and glycine, aimed at increasing the availability of …
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Aqueous systems from first-principles : structure, dynamics and electron-transfer reactions
… free-energy surfaces of electron-transfer reactions. The excitation energy corresponding to the transfer of an electron at any given ionic configuration (the Marcus energy gap) is accurately assessed within ground-state density-functional theory via a novel penalty functional for …
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Sorghum phenolic extracts : their storage stability and antioxidant activity in sunflower oil
… activities. The effect of oxidizing conditions during extraction, and the storage stability of a freeze-dried crude phenolic extract (CPE) from the condensed tannin sorghum bran as influenced by packaging, storage temperature and length of storage, in relation to its content of total …
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Kinetic Studies of Sulfide Mineral Oxidation and Xanthate Adsorption
… during mining and processing and SO2 emissions during smelting process. A part of the present study is focused on understanding their behavior, which leads to undesired flotation and difficulties in separation. The major reasons for the undesired flotation are attributed to the …
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Pretreatment of coal by anodic electrolysis of acidified coal- water slurries
… of the pretreatment were examined as functions of coal particle size, acid strength of the slurry, time of electrolysis and applied potential. The coal electrolysis was found to be most efficient at low acid strengths and short electrolysis times. The morphology of the coal surface changed …
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Reactivity of Iron-Bearing Minerals Under Carbon Sequestration Conditions
… were conducted to test the potential of ferric-bearing minerals to sequester carbon as a ferrous carbonate mineral (siderite). The formation of siderite requires the reduction of ferric ions which may be achieved by the co-injection of H2S or SO2 contaminants with CO2. Both ferrihydrite …
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Hydrometallurgical processing of nickel sulfides with activated carbon in sulfuric acid medium
… recoverability under appropriate chemical conditions. The findings from acid-base accounting further revealed that cleaner tailings pose a heightened risk of acid mine drainage generation due to depletion of reactive carbonates and Mg‑silicates responsible for acid neutralization during sulfide …
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Electrocatalytically induced liberation of mineral matter from coal
… overlap. In this technique, coal is exposed to ferric ions in an acidic medium which causes the coal to lose electrons and become positively charged, thereby establishing ionic double layers in the vicinity of its surface. Inside the pores and crevices in which mineral matter is entrapped, the …
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Scale-up and Measurement Enhancements of a BioGenerator Bioreactor
… grid supply-demand stabilization using a ferric sulfate oxidant is herein explored, named the BioGenerator. As the name implies, the system functions as an indirect microbial fuel cell using a biologically active broth dominated by the iron oxidizing microbe Leptospirillum ferriphilum …
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RECYCLING OF PRECIOUS METALS FROM WASTE PRINTED CIRCUIT BOARDS VIA A COMBINATION OF PYRO AND HYDROMETALLURGICAL PROCESSES
… materials, as they contain higher concentrations of precious metals than other electronic waste. Hydrometallurgical and pyrometallurgical processes are widely employed to recover metallic components from waste PCBs. Typically, mechanical separation is the initial step, followed by leaching …
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Prebiotic photoreduction and polymerization of cysteinyl peptides.
… to coordinate iron-sulfur clusters. Mixtures of ferric ions and cysteinyl peptides leads to the reduction of ferric to ferrous ions and the concomitant formation of disulfide bridged, oxidized cysteinyl peptides that are incapable of coordinating an iron-sulfur cluster. Here, we develop a …
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Sustainable Mining - Solving the Problem of Chalcopyrite Treatment/Processing - Leaching, Solvent Extraction & Flotation
… the most difficult to treat using conventional ferric leaching methods. Smelting and electro-refining are currently the methods used in treating chalcopyrite concentrate obtained from froth flotation. Due to the ever increasing environmental requirements on smelters by the Environmental …
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Bioleaching of chalcopyrite
… studied in shake flasks by employing cell suspensions in the chalcopyrite concentrate with the ATCC 64 medium in the absence of added ferrous ions. The characterisation of T. ferrooxidans on chalcopyrite concentrate was examined by investigating the adsorption isotherm and electrophoretic …
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The genesis of the blue amphibole asbestos of the Union of South Africa.
… years. This fact is related to special conditions of atmosphere, surface temperature and biological development which existed during the so-called Primitive Period of the Precambrian, a period which lasted from approximately 3000 million years to 1000 million years ago. The banded ironstones …
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Critical Elements Recovery from Acid Mine Drainage
… electronics, and other advanced applications. The demand for these elements has been growing exponentially in recent years, driven by the rise of electric vehicles, renewable energy, and other emerging technologies. However, the United States is heavily dependent on foreign sources of …
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