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Detail publikace
| Originální název: | New insights into aggregation and conformational behaviour of humic substances: Application of high resolution ultrasonic spectroscopy |
|---|---|
| Český název: | Nový pohled na agregační chování huminových kyselin: aplikace vysoce rozslišovací ultrazvukové spektroskopie |
| Anglický název: | New insights into aggregation and conformational behaviour of humic substances: Application of high resolution ultrasonic spectroscopy |
| Autor(ři): | KUČERÍK, J.; ŠMEJKALOVÁ, D.; ČECHLOVSKÁ, H.; PEKAŘ, M. |
| Typ: | článek v časopise |
| Jazyk: | en |
| Originální abstrakt: | The potential of high resolution ultrasonic analysis (HRUS) in humic acid colloidal properties research has been demonstrated. Sodium salts of humic acids from soil and lignite showed similar behaviour, supporting the hypothesis that, at both neutral and alkaline pH, they aggregate from very low concentration. The same conclusion can be reached for solutions at high ionic strength. We tried to apply the same procedure as used for the study of micellization and determination of critical micelle concentration of common surfactants. As expected, our experiments did not show the same break as demonstrated on the HRUS records for sodium dodecyl sulfate, at least in the range of measured concentration (i.e. from 0.001 up to 10 g/L). The colloidal state of humic acids in aqueous solution is very sensitive to the presence of other, both charged and neutral, molecules. Aggregation of humic acids can be disturbed or promoted, depending on the concentration, by electrostatic or other weak interactions with extraneous molecules. Structures of varying mechanical strength (rigidity) can be formed in solutions of the same components but at different concentration. Such behaviour reflects mechanisms which occur during the sequestration of hydrophobic organic compounds and has several implications for the protection/ transportation of labile structures and contaminants which are hypothesized to be encapsulated within hydrophobic pockets of soluble humic aggregates. |
| Český abstrakt: | Nový pohled na agregační chování huminových kyselin: aplikace vysoce rozslišovací ultrazvukové spektroskopie |
| Anglický abstrakt: | The potential of high resolution ultrasonic analysis (HRUS) in humic acid colloidal properties research has been demonstrated. Sodium salts of humic acids from soil and lignite showed similar behaviour, supporting the hypothesis that, at both neutral and alkaline pH, they aggregate from very low concentration. The same conclusion can be reached for solutions at high ionic strength. We tried to apply the same procedure as used for the study of micellization and determination of critical micelle concentration of common surfactants. As expected, our experiments did not show the same break as demonstrated on the HRUS records for sodium dodecyl sulfate, at least in the range of measured concentration (i.e. from 0.001 up to 10 g/L). The colloidal state of humic acids in aqueous solution is very sensitive to the presence of other, both charged and neutral, molecules. Aggregation of humic acids can be disturbed or promoted, depending on the concentration, by electrostatic or other weak interactions with extraneous molecules. Structures of varying mechanical strength (rigidity) can be formed in solutions of the same components but at different concentration. Such behaviour reflects mechanisms which occur during the sequestration of hydrophobic organic compounds and has several implications for the protection/ transportation of labile structures and contaminants which are hypothesized to be encapsulated within hydrophobic pockets of soluble humic aggregates. |
| Klíčová slova: | huminové látky, agregace, vysoce rozlišovací ultrazvuková spektroskospie |
| Rok RIV: | 2007 |
| Vydáno: | 09.08.2007 |
| Nakladatel: | Elsevier |
| Strany od: | 2098 |
| Strany do: | 2110 |
| Strany počet: | 13 |
