The Role of Concentration and Solvent Character in the Molecular Organization of Humic Acids

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26310%2F16%3APU120763" target="_blank" >RIV/00216305:26310/16:PU120763 - isvavai.cz</a>

Výsledek na webu

<a href="http://www.mdpi.com/1420-3049/21/11/1410" target="_blank" >http://www.mdpi.com/1420-3049/21/11/1410</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/molecules21101410" target="_blank" >10.3390/molecules21101410</a>

Jazyk výsledku

angličtina

Název v původním jazyce

The Role of Concentration and Solvent Character in the Molecular Organization of Humic Acids

Popis výsledku v původním jazyce

The molecular organization of humic acids in different aqueous solutions was studied over a wide concentration range (0.01–10 g/dm3). Solutions of humic acids were prepared in three different media: NaOH, NaCl, and NaOH neutralized by HCl after dissolution of the humic sample. Potentiometry, conductometry, densitometry, and high resolution ultrasound spectrometry were used in order to investigate conformational changes in the humic systems. The molecular organization of humic acids in the studied systems could be divided into three concentration ranges. The rearrangements were observed at concentrations of ~0.02 g/dm3 and ~1 g/dm3. The first “switch-over point” was connected with changes in the hydration shells of humic particles resulting in changes in their elasticity. The compressibility of water in the hydration shells is less than the compressibility of bulk water. The transfer of hydration water into bulk water increased the total compressibility of the solution, reducing the ultrasonic velocity. The aggregation of humic particles and the formation of rigid structures in systems with concentrations higher than 1 g/dm3 was detected.

Název v anglickém jazyce

The Role of Concentration and Solvent Character in the Molecular Organization of Humic Acids

Popis výsledku anglicky

The molecular organization of humic acids in different aqueous solutions was studied over a wide concentration range (0.01–10 g/dm3). Solutions of humic acids were prepared in three different media: NaOH, NaCl, and NaOH neutralized by HCl after dissolution of the humic sample. Potentiometry, conductometry, densitometry, and high resolution ultrasound spectrometry were used in order to investigate conformational changes in the humic systems. The molecular organization of humic acids in the studied systems could be divided into three concentration ranges. The rearrangements were observed at concentrations of ~0.02 g/dm3 and ~1 g/dm3. The first “switch-over point” was connected with changes in the hydration shells of humic particles resulting in changes in their elasticity. The compressibility of water in the hydration shells is less than the compressibility of bulk water. The transfer of hydration water into bulk water increased the total compressibility of the solution, reducing the ultrasonic velocity. The aggregation of humic particles and the formation of rigid structures in systems with concentrations higher than 1 g/dm3 was detected.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

<a href="/cs/project/LO1211" target="_blank" >LO1211: Centrum materiálového výzkumu na FCH VUT v Brně - udržitelnost a rozvoj</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2016

Kód důvěrnosti údajů

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

Název periodika

MOLECULES

ISSN

1420-3049

e-ISSN

—

Svazek periodika

21

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

9

Strana od-do

1410-1418

Kód UT WoS článku

000389918200001

EID výsledku v databázi Scopus

2-s2.0-84993940033