Publication detail

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

KLUČÁKOVÁ, M. VĚŽNÍKOVÁ, K.

Original Title

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

Type

journal article in Web of Science

Language

English

Original Abstract

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.

Keywords

humic acid; molecular organization; conformation; aggregation; ultrasound spectrometry

Authors

KLUČÁKOVÁ, M.; VĚŽNÍKOVÁ, K.

Released

21. 10. 2016

Publisher

MDPI AG

Location

Basel, Switzerland

ISBN

1420-3049

Periodical

MOLECULES

Year of study

21

Number

1

State

Swiss Confederation

Pages from

1410

Pages to

1418

Pages count

9

URL

http://www.mdpi.com/1420-3049/21/11/1410

Full text in the Digital Library

http://hdl.handle.net/11012/68390

BibTex

@article{BUT129206,
  author="Martina {Klučáková} and Kateřina {Věžníková}",
  title="The Role of Concentration and Solvent Character in the Molecular Organization of Humic Acids",
  journal="MOLECULES",
  year="2016",
  volume="21",
  number="1",
  pages="1410--1418",
  doi="10.3390/molecules21101410",
  issn="1420-3049",
  url="http://www.mdpi.com/1420-3049/21/11/1410"
}