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Detail publikace
KUČERÍK, J., CONTE, P., PEKAŘ, M., PICCOLO, A.
Originální název
Conformational behavior of lignite humic fractions separated by sequential pH-extractions
Typ
článek v časopise - ostatní, Jost
Jazyk
angličtina
Originální abstrakt
A bulk humic acid (HA) extracted from a South Moravian lignite was further fractionated by sequential extraction in buffers at different pHs. All samples were analyzed by high performance size exclusion chromatography (HPSEC) and elemental analysis. Weight-averaged molecular weights (Mw) of fractions dissolved at pH 7, 8, and 9 were larger than for the parent bulk HA, thereby indicating that Mw of humic matter is related only to molecular size as affected by sample hydration rather than its molecular mass. Moreover, hydration radius was a function of the specific chemical properties of humic fractions. Addition of small amount of either mineral (HCl) or organic acid (formic, acetic, propionic) to humic solutions induced significant changes in conformational arrangements of the treated sample in respect to control. Also the conformational changes among humic fractions depended on their different molecular composition and suggested a weakly-bound supramolecular association of different humic molecules in solution.
Klíčová slova
humic substances, lignite, HPSEC
Autoři
Rok RIV
2003
Vydáno
1. 1. 2003
ISSN
1018-4619
Periodikum
Fresenius Environmental Bulletin
Ročník
12
Číslo
7
Stát
Spolková republika Německo
Strany od
683
Strany do
689
Strany počet
BibTex
@article{BUT41503, author="Jiří {Kučerík} and Pelegrino {Conte} and Miloslav {Pekař} and Alessandro {Piccolo}", title="Conformational behavior of lignite humic fractions separated by sequential pH-extractions", journal="Fresenius Environmental Bulletin", year="2003", volume="12", number="7", pages="7", issn="1018-4619" }