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Showing 1 to 20 of 38 for “"humic acids"”.
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Functional Groups of Soil Humic Acids
Made available in DSpace on 2014-12-10T17:12:30Z (GMT). No. of bitstreams: 1 6706573.pdf: 4436093 bytes, checksum: 1ada50ce9686c7d5981c2ede56cd4c63 (MD5) Previous issue date: 1966
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The Chemistry of Soil Humic Acids
Made available in DSpace on 2014-12-04T20:17:11Z (GMT). No. of bitstreams: 1 6200670.pdf: 3987544 bytes, checksum: 1377efe8824f0f7fb840758daf7f176e (MD5) Previous issue date: 1961
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Some Studies on the Extraction and Chemical Properties of Soil Humic Acids
Made available in DSpace on 2014-12-04T20:16:54Z (GMT). No. of bitstreams: 1 0020854.pdf: 3227472 bytes, checksum: ad375c5c2e3c5bd8961c53d6a3a32d4d (MD5) Previous issue date: 1957
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Sorption of pentachlorophenol to humic acids and subsequent effects on biodegradation and solvent extraction
… mineral surfaces, these experiments used only humic acids extracted from soil samples. The major focus of this study was to examine the effects of solution pH, humic acid concentration and contact time on the degree of sorption. The association reactions proceeded slowly. Even after 28 days, …
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Amide and Ester-Functionalized Humic Acid for Fuel Combustion Enhancement
Humic acid is a class of naturally occurring molecules composed of large sheet-like regions of cyclic aromatic hydrocarbon networks with surface and edge functional groups including phenols, carboxylic acids, and epoxides. These naturally occurring molecules are found in brown coal deposits near …
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Metal Extraction From Soil Samples By Chelation in a Microwave System
… a sample set was first treated with humic acids, which represented organic coated materials. Afterwards, copper (II) solutions were spiked to both untreated and treated matrices and the efficiencies of recoveries were studied. Metal determinations were performed by Inductively Coupled …
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Some aspects of the interaction of humic substances with metal ions
Humic substances are the major organic constituents of soils and sediments. They are heterogeneous, polyfunctional, polydisperse, macromolecular and have no accurately known chemical structure. Their interactions with radionuclides are particularly important since they provide leaching mechanisms …
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Enhanced biohydrogen production and substrate utilization by co-culture fermentation with reduced extracellular electron shuttles
… including indigo dye, juglone, lawsone, fulvic acids and humic acids as alternative extracellular electron shuttles. The observed improvements in utilization of lignocellulosic hydrolysates and particularly utilization of xylose III support the feasibility of applying this co-culture system to …
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The role of biopolymers in thickening and dewatering of activated sludge
… partially of proteins, carbohydrates and humic acids. The relationship between supernatant biopolymer and sludge settling and dewatering characteristics is system specific. Sludge dewatering rates and supernatant biopolymer concentration vary drastically as sludge pH was increased from pH …
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Distribution of Colloidal Material in Activated Sludge as Influenced by Cations
… of organic nitrogen, organic carbon, protein, humic acid, and polysaccharide was examined with respect to the concentration of cations in the activated sludge influent. It was found that the majority of organic nitrogen, organic carbon, protein and polysaccharides were found in material larger …
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Identification And Analysis Of Genes Involved In Anaerobic Nitrate-Dependent Iron Oxidation
… perchlorate and anaerobically oxidizing benzene, humic acids, and ferrous iron. In addition, a newly-isolated β-proteobacterium, <i>Diaphorobacter</i> sp. strain TPSY, is of interest due to its ability to anaerobically oxidize humic acids, uranium, and ferrous iron. Thus, these two strains …
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The Description and Interpretation of a Tertiary Siliceous Rock in Western North Dakota
… a result of the introduction of CO2 and/or humic acids due to the decomposition of organic matter. </p><p>Limited evidence suggests a multiple-horizon source for the siliceous rock.</p>
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Investigating nitrate-dependent humic substance oxidation and in-service K-12 teachers' understanding of microbiology
<p>Humic substances (HS) are the humified portions of totally decomposed soil organic matter that are ubiquitous in nature. Although these substances have been studied for more than 200 years, neither their metabolic capabilities nor a specific chemical structure has yet to be determined. HS have …
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The Photodegradation of Diazepam and its Human Metabolites in Water
… of natural organic matter (NOM), specifically humic acids at environmental levels (1 mg Lˉ¹) were found to approximately double the rate of photodegradation for diazepam and nordiazepam (t½ 28 and 48 hours respectively). In contrast, results for the metabolites temazepam and oxazepam suggest …
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Determinants of blackwaters in the South Western Cape
… The Fe in the water appears to be bound to humic compounds. Fynbos vegetation is able to produce greater concentrations of polyphenol leachates (315 mg/l humic acid) compared to savanna species (246 mg/ humic acid) over a four-day period. P fertilisations increased the concentrations of …
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Hazardous waste treatment and disposal: alternative technologies and groundwater impacts
… and complexing with organic matter such as humic acids. Many field studies with landfarmed metal-bearing wastes show that these mechanisms are usually sufficient to retain metals to within several inches of their zone of application.
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Factors Affecting Mobility of Copper in Soil-Water Matrices
… and column processes. The effects of pH, TOC and humic substances were investigated. The mobility of copper was found to be higher through A-horizon soil. The pH was found to have a considerable effect on the mobility of copper and TOC. The highest mobility of copper was achieved at pH 6.24 and …
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