Results 151 to 160 of about 493,503 (195)

Antioxidant Properties of Humic Substances

Environmental Science & Technology, 2012
Humic substances (HS) are heterogeneous, redox-active organic macromolecules. While electron transfer to and from HS under reducing conditions is well investigated, comparatively little is known on the electron donating (i.e., antioxidant) properties of HS under oxic conditions.
Aeschbacher M, Graf C, Schwarzenbach RP, Sander M   +3 more
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Adsorption of Glyphosate by Humic Substances

Journal of Agricultural and Food Chemistry, 1996
Four humic substances were extracted from a peat (HA1) and a volcanic soil (HA2), an oxidized coal (HA3), and a lignite (HA4). The four humic materials presented distinct differences in their chemical and physical−chemical characteristics as assessed by chemical methods, 13C-NMR spectroscopy, and high-performance size exclusion chromatography.
A. PICCOLO, CELANO, Giuseppe, P. CONTE
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Removal of humic substances by biosorption

Journal of Environmental Sciences, 2008
Fungal pellets of Aspergillus niger 405, Aspergillus ustus 326, and Stachybotrys sp. 1103 were used for the removal of humic substances from aqueous solutions. Batchwise biosorption, carried out at pH 6 and 25 degrees C, was monitored spectrophotometrically and the process described with Freundlich's model.
Vuković Domanovac, Marija, Domanovac, Tomislav, Briški, Felicita   +2 more
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Antiandrogenic activity of humic substances

Science of The Total Environment, 2012
For long, natural organic matter (NOM) composed mainly of humic substances (HS) were regarded as inert in the ecosystems with respect to their possible chemical interaction with exposed organisms. However recently, NOM have been shown to elicit various adverse effects generally attributed to synthetic xenobiotics, including estrogenic effects ...
Michal, Bittner, Nadine, Saul, Christian E W, Steinberg   +2 more
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Involvement of humic substances in regrowth

International Journal of Food Microbiology, 2004
There appear to be interactions in the distribution system that complicate the ability to use AOC/BDOC as an independent assessment of regrowth potential. Two such complications are the limitation of the assays themselves and the potential interaction between the organic carbon concentration with the presence of disinfectants and pipe materials.
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Humic Substances and Plant Nutrition

1995
Since the studies by Liebig (1856), it is well known that plants, as long as they are adequately supplied with light and mineral nutrients, can live in the absence of the organic and inorganic structural components of the soil. Nowadays the use of hydroponics is popular not only among plant physiologists but also in certain commercial activities.
VARANINI, Zeno, R. PINTON
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Human lung injury following exposure to humic substances and humic-like substances

Environmental Geochemistry and Health, 2017
Among the myriad particles the human respiratory tract is exposed to, a significant number are distinctive in that they include humic substances (HS) and humic-like substances (HULIS) as organic components. HS are heterogeneous, amorphous, organic materials which are ubiquitous occurring in all terrestrial and aqueous environments.
Andrew J. Ghio, Michael C. Madden
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On the nature of humic substances

Eurasian Soil Science, 2015
It is argued that the isolation of low-molecular-weight compounds from humic substances does not prove their supramolecular nature, because small molecules can be sorbed on macromolecules by interacting with them due to noncovalent bonds. The relative mobility of molecular segments in humic substances has been proposed to be used as a criterion for the
G. N. Fedotov, S. A. Shoba
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Radioiodination of humic substances

Radiochimica Acta, 2010
AbstractThe known IODO-GEN™-method [1] was adapted for radiolabeling of humic and fulvic acids with131I. The water insoluble oxidizing agent 1,3,4,6tetrachloro-3α,6α-diphenylglycoluril (IODO-GEN™) forms an iodous ion species (I+), which undergoes an electrophilic I/H-substitution on aromatic moieties of the humic and fulvic acids.
Franke, K., Kupsch, H.
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Immobilisation of humic substances

Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2002
Attempts were made to immobilise humic substances (HS) by grafting them onto different carriers (styrene-divinylbenzene copolymers, cellulose and silica) as well as by their crosslinking with formaldehyde. Reaction with Merrifield resin was used for the immobilisation of HS, coupling by means of water-soluble carbodiimides to carriers containing amino ...
M Klavins, L Eglı̄te
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