Lignite humic acids aggregates studied by high resolution ultrasonic spectroscopy. Thermodynamic stability and molecular feature.

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26310%2F09%3APU83582" target="_blank" >RIV/00216305:26310/09:PU83582 - 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

Lignite humic acids aggregates studied by high resolution ultrasonic spectroscopy. Thermodynamic stability and molecular feature.

Original language description

The thermodynamic stability of lignite humic acids (sodium salt) aggregates was studied by high resolution ultrasonic spectroscopy within the temperature interval from 5 to 90C. The changes in differential ultrasonic velocity (U12) showed strong differences among humic solutions within the concentration range from 0.005 to 10 g/L. Measurement revealed several transitions which were attributed to the weakening of humic secondary structure. Concentration around 1 g/L seemed to be a limit under which the change of the prevalence and importance of hydration occurred. Above this concentration the difference in U12 decreased following the temperature increase which was explained as a dominance of hydrophilic hydration. In contrast, below this concentration,the temperature dependence of U12 resulted in increasing tendency which was attributed to the prevalence of hydrophobic hydration, i.e. uncovering of apolar groups towards surrounding water. Additional experiments in which the humic sampl

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

<a href="/en/project/GP104%2F05%2FP513" target="_blank" >GP104/05/P513: Stability of humic acids</a><br>

Continuities

Z - Vyzkumny zamer (s odkazem do CEZ)

Publication year

2009

Confidentiality

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

Name of the periodical

Journal of Thermal Analysis and Calorimetry

ISSN

1388-6150

e-ISSN

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Volume of the periodical

96

Issue of the periodical within the volume

2

Country of publishing house

HU - HUNGARY

Number of pages

7

Pages from-to

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UT code for WoS article

000266482600045

EID of the result in the Scopus database

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