Detail publikačního výsledku

Conformational behavior of lignite humic fractions separated by sequential pH-extractions

KUČERÍK, J., CONTE, P., PEKAŘ, M., PICCOLO, A.

Originální název

Conformational behavior of lignite humic fractions separated by sequential pH-extractions

Anglický název

Conformational behavior of lignite humic fractions separated by sequential pH-extractions

Druh

Článek recenzovaný mimo WoS a Scopus

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.

Anglický 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

Klíčová slova v angličtině

humic substances, lignite, HPSEC

Autoři

KUČERÍK, J., CONTE, P., PEKAŘ, M., PICCOLO, A.

Vydáno

01.01.2003

ISSN

1018-4619

Periodikum

Fresenius Environmental Bulletin

Svazek

12

Číslo

7

Stát

Spolková republika Německo

Strany od

683

Strany počet

7

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"
}