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

Kód výsledku v 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>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

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

Popis výsledku v původním jazyce

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

Název v anglickém jazyce

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

Popis výsledku anglicky

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

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

CF - Fyzikální chemie a teoretická chemie

OECD FORD obor

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Projekt

<a href="/cs/project/GP104%2F05%2FP513" target="_blank" >GP104/05/P513: Stabilita huminových kyselin</a><br>

Návaznosti

Z - Vyzkumny zamer (s odkazem do CEZ)

Rok uplatnění

2009

Kód důvěrnosti údajů

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

Název periodika

Journal of Thermal Analysis and Calorimetry

ISSN

1388-6150

e-ISSN

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Svazek periodika

96

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

HU - Maďarsko

Počet stran výsledku

7

Strana od-do

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Kód UT WoS článku

000266482600045

EID výsledku v databázi Scopus

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