Agregace organických látek ve zmrzlých vodných roztocích
The pure polycrystaline ice is formed during freezing of aqueous solutions. Most of the solutes are expelled to the grain boundaries of ice crystals. The UV/vis absorption spectroscopy of the various organic compounds frozen in the aqueous solutions was used to elucidate the changes in absorption sp...
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| Typ dokumentu: | VŠ práce nebo rukopis |
| Jazyk: | Čeština |
| Vydáno: |
2006.
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| On-line přístup: | https://is.muni.cz/auth/th/11279/prif_d/ |
| Shrnutí: | The pure polycrystaline ice is formed during freezing of aqueous solutions. Most of the solutes are expelled to the grain boundaries of ice crystals. The UV/vis absorption spectroscopy of the various organic compounds frozen in the aqueous solutions was used to elucidate the changes in absorption spectra and to characterize the amount of aggregation of organic compounds, H+ and OH- ions availabilities, as well as solvatochromic properties. Molecular aggregations in ice change the absorption characteristics of the organic molecules due to changed interactions with the host water molecules of the cavity as well as intermolecular interactions among the solute molecules themselves. The extent of aggregation of organic compounds was studied on a model compound (methylene blue). The absorption spectra of this compound are known to change upon aggregation. The re-evaluated equilibrium constants of dimerization and trimerization in liquid water solution allowed us to estimate local concentrations in the frozen samples. |
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| Popis jednotky: | Vedoucí práce: Petr Klán. |
| Fyzický popis: | 1 CD-ROM. |