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Interaction between humic substances and metallic ions: A selectivity study of humic substances and their possible therapeutic application
(2007-09-06)
The complexation capacity of humic substances extracted from peat samples taken from the Mogi River in Ribeirao Preto, SP, Brazil, was determined using metal ions (Al(III), Pb(II), Cr(VI) and Cd(II)), yielding the following ...
Atrazine interaction with tropical humic substances by Enzyme Linked Immunosorbent Assay
(E D P Sciences, 1998-04-01)
Enzyme-Linked Immunosorbent Assay (ELISA) has been evaluated by analyzing rich-humic water samples from tropical rivers. The samples were spiked with atrazine at ppb level Different pHs (4 to 9) and humic concentrations ...
An alternative methodology for the extraction of humic substances from organic soils
(1998-12-01)
The present study reports on an alternative methodology for the extraction of Humic Substances (HS) from the soil. The extractions were carried out with 0.5 M KOH for 3 h, at a ratio of 1:20 (m/v) under a nitrogen atmosphere. ...
Studies on the interaction between humic substances and conducting polymers for sensor application
(2005-01-01)
The interaction between humic substances and poly(o-ethoxyaniline) (POEA), a conducting polymer, was investigated for both solution and self-assembled films. The results have shown that the humic substances induce a doping ...
Substâncias húmicas de turfa: estudo dos parâmetros que influenciam no processo de extração alcalina
(Sociedade Brasileira de Química, 2000-08-01)
This study reports the parameters which influence on extraction of humic substances (HS) from peat. The yield, organic and inorganic contend, E4/E6 ratio and elemental composition (C,H,N) of the extracted HS have been ...
A new application of humic substances: Activation of supports for invertase immobilization
(2000-12-01)
Invertase was immobilized on aminopropyl silica (APTS-SiO2) activated with humic substances (APTS-SiO2-HS) and on aminopropyl silica activated with glutaraldehyde (APTS-SiO2-GA). The resulting activity of both systems was ...
Influence of alkaline extraction on the characteristics of humic substances in Brazilian soils
(Elsevier B.V., 2005-08-01)
An investigation was made of the influence of alkaline extraction on the characteristics of humic substances extracted from Brazilian soil samples. Humic substances (HS) from seven different soils samples collected in ...
Influence of Seasonality on the Interaction of Mercury with Aquatic Humic Substances Extracted from the Middle Negro River Basin (Amazon)
(Soc Brasileira Quimica, 2012-09-01)
High mercury concentrations in different environmental matrices in the Amazon have been attributed to mining activities. However, high concentrations of mercury are also present in the soil and water in places like in the ...
The influence of seasonalness on the structural characteristics of aquatic humic substances extracted from Negro River (Amazon state) waters: Interactions with Hg(II)
(2007-09-06)
In this work, humic substances were extracted from water samples collected monthly from the Negro River basin in the Amazon state (Brazil) to study their properties in the Amazonian environment and interactions with the ...
Competition between humic substances and α-amino acids by metal species
(2004-08-30)
The aim of the present work was to carry out experimental comparison between humic substances (HS) and representative α-amino acids (methionine, methionine sulfoxide and cysteine hydrochloride) in relation to the complexation ...