2005
Aggregation of Methylene Blue in Frozen Aqueous Solutions Studied by Absorption Spectroscopy
HEGER, Dominik, Jaromír JIRKOVSKÝ a Petr KLÁNZákladní údaje
Originální název
Aggregation of Methylene Blue in Frozen Aqueous Solutions Studied by Absorption Spectroscopy
Název česky
Aggregation of Methylene Blue in Frozen Aqueous Solutions Studied by Absorption Spectroscopy
Autoři
HEGER, Dominik (203 Česká republika), Jaromír JIRKOVSKÝ (203 Česká republika) a Petr KLÁN (203 Česká republika, garant)
Vydání
Journal of Physical Chemistry A, USA, The American Chemical Society, 2005, 1089-5639
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10403 Physical chemistry
Stát vydavatele
Spojené státy
Utajení
není předmětem státního či obchodního tajemství
Impakt faktor
Impact factor: 2.898
Kód RIV
RIV/00216224:14310/05:00012597
Organizační jednotka
Přírodovědecká fakulta
UT WoS
000230897000012
Klíčová slova anglicky
photochemistry; aggregation; methylene blue
Štítky
Příznaky
Mezinárodní význam
Změněno: 23. 6. 2009 15:19, prof. RNDr. Petr Klán, Ph.D.
V originále
The paper presents a qualitative as well as quantitative spectroscopic study of methylene blue (MB) aggregation that occurs upon freezing the aqueous solutions over a wide concentration range. The Gaussian curve analysis and the multivariate curve resolution-alternating least squares method were used to determine the number and concentration of chemical species responsible for the overlaying absorption visible spectra measured. The results show the extent of aggregation for the concentrations above 10(-7) mol L(-1), being dependent on the freezing rate and the initial concentration. While the local concentration of MB at the grain boundaries of polycrystalline ice increased by approximately 3 orders of magnitude upon fast freezing at 77 K compared to the liquid phase, the concentration raised at least by 6 orders of magnitude upon slow freezing at 243 K. Since enhancement of the local concentration of solutes plays an important role in (photo)chemical transformations in solid aqueous media, this work helps to understand how the initial conditions control the course of the process. The results are relevant in other interdisciplinary fields, such as environmental chemistry, cosmochemistry, or geochemistry.
Česky
The paper presents a qualitative as well as quantitative spectroscopic study of methylene blue (MB) aggregation that occurs upon freezing the aqueous solutions over a wide concentration range. The Gaussian curve analysis and the multivariate curve resolution-alternating least squares method were used to determine the number and concentration of chemical species responsible for the overlaying absorption visible spectra measured. The results show the extent of aggregation for the concentrations above 10(-7) mol L(-1), being dependent on the freezing rate and the initial concentration. While the local concentration of MB at the grain boundaries of polycrystalline ice increased by approximately 3 orders of magnitude upon fast freezing at 77 K compared to the liquid phase, the concentration raised at least by 6 orders of magnitude upon slow freezing at 243 K. Since enhancement of the local concentration of solutes plays an important role in (photo)chemical transformations in solid aqueous media, this work helps to understand how the initial conditions control the course of the process. The results are relevant in other interdisciplinary fields, such as environmental chemistry, cosmochemistry, or geochemistry.
Návaznosti
| GA205/05/0819, projekt VaV |
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| MSM0021622412, záměr |
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