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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 ...
Toxicity assessment of arsenic and cobalt in the presence of aquatic humic substances of different molecular sizes
(2017-05-01)
The release of contaminants in aquatic ecosystems can be influenced by humic acids. In this study, toxicity tests using environmentally relevant concentrations of arsenic and cobalt were conducted both in the presence and ...
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 ...
Toxicity assessment of arsenic and cobalt in the presence of aquatic humic substances of different molecular sizes
(Elsevier B.V., 2017-05-01)
using environmentally relevant concentrations of arsenic and cobalt were conducted both in the presence and absence of aquatic humic substances (AHS) and the fractions of different molecular sizes in the range of (< 5, ...
Realistic soil C sink estimate in dry forests of western Argentina based on humic substance content
(Elsevier, 2013-02)
Due to high temporal variation of soil organic matter in arid regions, estimates of annual sequestered C might be overestimate. We assessed the soil stable organic matter (humic substances) in the transitional area between ...
Aquatic Humic Substances: Relationship Between Origin and Complexing Capacity
(Springer, 2018-05-01)
Aiming to determine the relationship between source and complexing capacity, humic substances obtained from three sites (Sorocaba and Itapanhau Brasilian rivers, and Xochimilco Lake in Mexico) were studied. Copper, manganese, ...
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 ...