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

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26310%2F03%3APU38208" target="_blank" >RIV/00216305:26310/03:PU38208 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

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

Original language description

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 maass. 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

Czech name

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Czech description

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Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

CF - Physical chemistry and theoretical chemistry

OECD FORD branch

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Project

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Continuities

Z - Vyzkumny zamer (s odkazem do CEZ)

Publication year

2003

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Fresenius Environmental Bulletin

ISSN

1018-4619

e-ISSN

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Volume of the periodical

12

Issue of the periodical within the volume

7

Country of publishing house

DE - GERMANY

Number of pages

7

Pages from-to

683-689

UT code for WoS article

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EID of the result in the Scopus database

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