Results 211 to 220 of about 16,763 (263)

Americium Binding to Humic Acid

Environmental Science & Technology, 2001
The binding of americium (Am) by peat humic acid (PHA) has been investigated at Am concentrations between 10(-1) and 10(-7) M at pH approximately 2.6 in the presence and absence of Cu as a competing ion. Cu-PHA binding was also investigated in order to derive independent binding constants for use in modeling the competitive binding studies.
Peters, Adam J., Hamilton-Taylor, John, Tipping, Edward   +2 more
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Electrochemical degradation of humic acid

Science of The Total Environment, 2000
The treatment of natural water for drinking water production goes through the degradation of humic substances. In this study, humic acid, extracted from a peat area located at the margins of the Mogi Guaçu River at São Paulo State, Brazil, was used to perform electro-oxidation essays in order to evaluate the possibilities of electrochemical methods in ...
A J, Motheo, L, Pinhedo
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Adsorption of Humic Substances on Goethite:  Comparison between Humic Acids and Fulvic Acids

Environmental Science & Technology, 2006
The adsorption of humic acids (HA) to goethite (at pH 3-11) and the proton co-adsorption (at pH 4.0, 5.5, and 7.0) were measured, and the results were compared to those of fulvic acids (FA). Compared to FA, the adsorption of HA is stronger and more ionic strength dependent. The adsorption of both HA and FA decreases with increasing pH.
Weng, L.P., van Riemsdijk, W.H., Koopal, L.K., Hiemstra, T.   +3 more
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Sorption of humic acids by bacteria

Microbiology, 2013
Capacity for sorption of humic acid (HA) from water solutions was shown for 38 bacterial strains. Isotherms of HA sorption were determined for the cells of 10 strains. The bonding strength between the cells and HA (k) and the terminal adsorption (Q(max)) determined from the Langmuir equation for gram-positive and gram-negative bacteria were reliably ...
V V, Tikhonov, D S, Orlov, O V, Lisovitskaia, Iu A, Zavgorodniaia, B A, Byzov, V V, Demin   +5 more
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Electrophoretic aggregation of humic acid

Journal of Chromatography A, 2004
Capillary electrophoresis (CE) has been used to characterize humic acid (HA) aggregation. It was found that when pumping HA solution through the capillary at a constant flow rate with no electric field, the number of spikes could be reduced by filtration of the solution. Applying high voltage (30 kV), the amount of spikes increased again.
Monika, Ubner, Viia, Lepane, Margus, Lopp, Mihkel, Kaljurand   +3 more
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Adsorption of mutagens by humic acid

Science of The Total Environment, 1987
Humic acid inhibited the mutagenicity of various mutagens. The inhibitory effect was desmutagenic, heat-resistant and increased with an increase of the humic acid molecular weight. Typical monomeric components of humic acids had no desmutagenic effect.
T, Sato, Y, Ose, H, Nagase, K, Hayase
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Methylation of Humic Acid Fractions

Science, 1978
A new three-step permethylation procedure for humic acid fractions has been developed. In the first step, carboxylic acid groups are methylated with diazomethane in dimethylformamide; in the second step, hydroxyl groups are methylated with methyl iodide and dimethyl sulfinyl carbanion in dimethylformamide; and in the third step, acidic groups ...
R L, Wershaw, D J, Pinckney
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Effects of humic acids in vitro

In Vitro Cellular & Developmental Biology - Animal, 2011
Humic acids are known for their overall positive health and productivity effects in animal feeding trials and, controversially, as an aetiological factor of cancer. We tried to assess the in vitro effect of humic acids from a selected source in Slovakia when used at recommended prophylactic dosage.
Janka, Vašková, Beáta, Veliká, Martina, Pilátová, Ivan, Kron, Ladislav, Vaško   +4 more
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Humic acid: Inhibitor of plasmin

Science of The Total Environment, 1992
Synthetic humic acid, well water humic acid and commercial humic acid (Aldrich) all have the ability to inhibit human plasmin activity. At a concentration of 20 micrograms/ml, all three species will result in 93%, 70% and 40% of residual plasmin activity, respectively. The components of humic acid, such as protocatechuic acid, resorcinol, vanillic acid
F J, Lu, Y S, Lee
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Antiviral properties of humic acids

Experientia, 1972
Es wird ein antiviraler Effekt von Ammoniumhumat gegenuber Coxsackiervirus A9 in FL-Zellkulturen nachgewiesen. Die antivirale Wirkung ist auf den Humatanteil des Molekuls zuruckzufuhren.
R, Klöcking, M, Sprössig
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