TY  - JOUR
AU  - Ilić, Marija A.
AU  - Haegel, Franz-Hubert
AU  - Pavelkić, Vesna
AU  - Zlatanović, Snežana
AU  - Marković, Zoran S.
AU  - Cvjetić, Aleksandar S.
PY  - 2015
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/3932
AB  - Microemulsion systems with water, toluene and nonionic surfactants are interesting for application due to the excellent solvent properties of aromatic hydrocarbons. In this study, the pseudo-binary phase diagram (“fish-diagram”) of such a ternary system was investigated using a branched technical alkyl polyethoxylate. Lutensol ON 50 (i-C10E5) was considered a suitable surfactant. The system with technical branched i-C10E5 exhibits very long, and for compositions near optimum solubilization, i.e., the minimum content of surfactant needed for a bicontinuous microemulsion, extremely long times for equilibration. In addition to visual observation, qualitative measurements of turbidity were performed with a UV-Vis spectrometer for characterizing the behavior of this unusually sluggish system. Isothermal phase diagrams at 20, 25 and 30 °C yielded inconsistent results after the change of temperature and the application of mechanical stress for different treatment of the samples. Ternary mixtures of water, toluene, and lutensol ON 50 seem to form long-living metastable states. The sluggishness and the ambiguous phase behavior of the system are discussed. Inconsistent results are attributed to the slow kinetics of the formation and destruction of liquid crystals and the ability of the system to form mini- -emulsions within an unusual concentration range.
AB  - Mikroemulzije na bazi vode, toluena i nejonskih površinski aktivnih supstanci su interesantni za primenu, zahvaljujući izvanrednim karakteristikama aromatičnih ugljovodonika kao rastvarača. U ovom radu, ispitivani su pseudo-binarni fazni dijagrami (“riba-dijagram”) ternatnih sistema upotrebom tehnički razgranatog alkil polietoksilata. Kao pogodana površinski aktivna supstanca korišćen je Lutensol ON 50 (i-C10E5). Sistem sa tehnički razgranatim i-C10E5 pokazuje izuzetno dugo vreme za postizanje ravnoteže, iako sardžaj površinski aktivne supstance u sistemu odgovara optimalnoj rastvorljivosti (tj. minimalnom sadržaju površinski aktivne supstance koji je neophodan za bi-kontinualnu mikroemulziju). Pored vizuelnog posmatranja, kvalitativno merenje zmućenosti je vršeno UV–Vis spektroskopijom da bi se okarakterisalo neuobičajeno sporo uspostavljanje ravnoteže u sistemu. Izotermni fazni dijagrami na 20, 25 i 30 °C dali su rezultate nekonzistentne promeni temperature i primeni mehaničkog opterećenje za različit tretman uzoraka. Trokomponentna smeša vode, toluena i Lutensol ON 50 formira dugoživeća metastabilna stanja. Diskutovana je sporost i dvosmislenost ponašanja ovakvog sistema. Nekonzistentni rezultati su pripisani sporoj kinetici formiranja i razlaganja tečnih kristala, kao i sposobnosti sistema da formira mini mikroemulzije unutar neuobičajenog opsega koncentracija.
PB  - Serbia : Association of Chemical Engineers of Serbia
T2  - Chemical Industry and Chemical Engineering Quarterly
T1  - Unusually sluggish microemulsion system with water, toluene and a technical branched alkyl polyethoxylate
VL  - 21
IS  - 3
SP  - 429
EP  - 439
DO  - 10.2298/CICEQ141012045I
ER  - 

@article{
author = "Ilić, Marija A. and Haegel, Franz-Hubert and Pavelkić, Vesna and Zlatanović, Snežana and Marković, Zoran S. and Cvjetić, Aleksandar S.",
year = "2015",
abstract = "Microemulsion systems with water, toluene and nonionic surfactants are interesting for application due to the excellent solvent properties of aromatic hydrocarbons. In this study, the pseudo-binary phase diagram (“fish-diagram”) of such a ternary system was investigated using a branched technical alkyl polyethoxylate. Lutensol ON 50 (i-C10E5) was considered a suitable surfactant. The system with technical branched i-C10E5 exhibits very long, and for compositions near optimum solubilization, i.e., the minimum content of surfactant needed for a bicontinuous microemulsion, extremely long times for equilibration. In addition to visual observation, qualitative measurements of turbidity were performed with a UV-Vis spectrometer for characterizing the behavior of this unusually sluggish system. Isothermal phase diagrams at 20, 25 and 30 °C yielded inconsistent results after the change of temperature and the application of mechanical stress for different treatment of the samples. Ternary mixtures of water, toluene, and lutensol ON 50 seem to form long-living metastable states. The sluggishness and the ambiguous phase behavior of the system are discussed. Inconsistent results are attributed to the slow kinetics of the formation and destruction of liquid crystals and the ability of the system to form mini- -emulsions within an unusual concentration range., Mikroemulzije na bazi vode, toluena i nejonskih površinski aktivnih supstanci su interesantni za primenu, zahvaljujući izvanrednim karakteristikama aromatičnih ugljovodonika kao rastvarača. U ovom radu, ispitivani su pseudo-binarni fazni dijagrami (“riba-dijagram”) ternatnih sistema upotrebom tehnički razgranatog alkil polietoksilata. Kao pogodana površinski aktivna supstanca korišćen je Lutensol ON 50 (i-C10E5). Sistem sa tehnički razgranatim i-C10E5 pokazuje izuzetno dugo vreme za postizanje ravnoteže, iako sardžaj površinski aktivne supstance u sistemu odgovara optimalnoj rastvorljivosti (tj. minimalnom sadržaju površinski aktivne supstance koji je neophodan za bi-kontinualnu mikroemulziju). Pored vizuelnog posmatranja, kvalitativno merenje zmućenosti je vršeno UV–Vis spektroskopijom da bi se okarakterisalo neuobičajeno sporo uspostavljanje ravnoteže u sistemu. Izotermni fazni dijagrami na 20, 25 i 30 °C dali su rezultate nekonzistentne promeni temperature i primeni mehaničkog opterećenje za različit tretman uzoraka. Trokomponentna smeša vode, toluena i Lutensol ON 50 formira dugoživeća metastabilna stanja. Diskutovana je sporost i dvosmislenost ponašanja ovakvog sistema. Nekonzistentni rezultati su pripisani sporoj kinetici formiranja i razlaganja tečnih kristala, kao i sposobnosti sistema da formira mini mikroemulzije unutar neuobičajenog opsega koncentracija.",
publisher = "Serbia : Association of Chemical Engineers of Serbia",
journal = "Chemical Industry and Chemical Engineering Quarterly",
title = "Unusually sluggish microemulsion system with water, toluene and a technical branched alkyl polyethoxylate",
volume = "21",
number = "3",
pages = "429-439",
doi = "10.2298/CICEQ141012045I"
}

Ilić, M. A., Haegel, F., Pavelkić, V., Zlatanović, S., Marković, Z. S.,& Cvjetić, A. S.. (2015). Unusually sluggish microemulsion system with water, toluene and a technical branched alkyl polyethoxylate. in Chemical Industry and Chemical Engineering Quarterly
Serbia : Association of Chemical Engineers of Serbia., 21(3), 429-439.
https://doi.org/10.2298/CICEQ141012045I

Ilić MA, Haegel F, Pavelkić V, Zlatanović S, Marković ZS, Cvjetić AS. Unusually sluggish microemulsion system with water, toluene and a technical branched alkyl polyethoxylate. in Chemical Industry and Chemical Engineering Quarterly. 2015;21(3):429-439.
doi:10.2298/CICEQ141012045I .

Ilić, Marija A., Haegel, Franz-Hubert, Pavelkić, Vesna, Zlatanović, Snežana, Marković, Zoran S., Cvjetić, Aleksandar S., "Unusually sluggish microemulsion system with water, toluene and a technical branched alkyl polyethoxylate" in Chemical Industry and Chemical Engineering Quarterly, 21, no. 3 (2015):429-439,
https://doi.org/10.2298/CICEQ141012045I . .

TY  - JOUR
AU  - Dimitrić Marković, Jasmina M.
AU  - Marković, Zoran S.
AU  - Veselinović, Dragan S.
AU  - Krstić, Jugoslav
AU  - Predojević, Simović J.D.
PY  - 2009
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/566
AB  - Spectroscopic (UV/visible and IR) and theoretical studies were used to assess relevant interaction of fisetin, a tetrahydroxylated flavone molecule, and trivalent aluminium in a wide range of buffered aqueous solutions. The chelation sites, stoichiometry, stability and the dependence of the complexes structures on pH and aluminium/fisetin mole ratios were defined. Obtained results implicated successive formation of two complexes with aluminium(III)-fisetin stoichiometries of 1:1 and 2:1. Considering the fisetin molecular structure, results of vibrational analysis and theoretical calculations, it is possible to implicate 3-hydroxyl-4-carbonyl and 3′4′-dihydroxyl groups as those with the possible chelating power. The equilibrium geometries were optimized in vacuum at the B3LYP/6-31G(d) level of theory, which predict structural modifications between the ligand molecule in free state and in the complex structure. The theoretical model has been validated by both vibrational and electronic spectroscopies.
PB  - Elsevier Science Inc, New York
T2  - Journal of Inorganic Biochemistry
T1  - Study on fisetin-aluminium(III) interaction in aqueous buffered solutions by spectroscopy and molecular modeling
VL  - 103
IS  - 5
SP  - 723
EP  - 730
DO  - 10.1016/j.jinorgbio.2009.01.005
ER  - 

@article{
author = "Dimitrić Marković, Jasmina M. and Marković, Zoran S. and Veselinović, Dragan S. and Krstić, Jugoslav and Predojević, Simović J.D.",
year = "2009",
abstract = "Spectroscopic (UV/visible and IR) and theoretical studies were used to assess relevant interaction of fisetin, a tetrahydroxylated flavone molecule, and trivalent aluminium in a wide range of buffered aqueous solutions. The chelation sites, stoichiometry, stability and the dependence of the complexes structures on pH and aluminium/fisetin mole ratios were defined. Obtained results implicated successive formation of two complexes with aluminium(III)-fisetin stoichiometries of 1:1 and 2:1. Considering the fisetin molecular structure, results of vibrational analysis and theoretical calculations, it is possible to implicate 3-hydroxyl-4-carbonyl and 3′4′-dihydroxyl groups as those with the possible chelating power. The equilibrium geometries were optimized in vacuum at the B3LYP/6-31G(d) level of theory, which predict structural modifications between the ligand molecule in free state and in the complex structure. The theoretical model has been validated by both vibrational and electronic spectroscopies.",
publisher = "Elsevier Science Inc, New York",
journal = "Journal of Inorganic Biochemistry",
title = "Study on fisetin-aluminium(III) interaction in aqueous buffered solutions by spectroscopy and molecular modeling",
volume = "103",
number = "5",
pages = "723-730",
doi = "10.1016/j.jinorgbio.2009.01.005"
}

Dimitrić Marković, J. M., Marković, Z. S., Veselinović, D. S., Krstić, J.,& Predojević, S. J.D.. (2009). Study on fisetin-aluminium(III) interaction in aqueous buffered solutions by spectroscopy and molecular modeling. in Journal of Inorganic Biochemistry
Elsevier Science Inc, New York., 103(5), 723-730.
https://doi.org/10.1016/j.jinorgbio.2009.01.005

Dimitrić Marković JM, Marković ZS, Veselinović DS, Krstić J, Predojević SJ. Study on fisetin-aluminium(III) interaction in aqueous buffered solutions by spectroscopy and molecular modeling. in Journal of Inorganic Biochemistry. 2009;103(5):723-730.
doi:10.1016/j.jinorgbio.2009.01.005 .

Dimitrić Marković, Jasmina M., Marković, Zoran S., Veselinović, Dragan S., Krstić, Jugoslav, Predojević, Simović J.D., "Study on fisetin-aluminium(III) interaction in aqueous buffered solutions by spectroscopy and molecular modeling" in Journal of Inorganic Biochemistry, 103, no. 5 (2009):723-730,
https://doi.org/10.1016/j.jinorgbio.2009.01.005 . .