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1

Spectrofluorymetry in application to oil-in-water emulsion characterization

Otremba Z., Baszanowska E., Toczek H.

Journal of KONES

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2011

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Vol. 18, No. 3

317-321

EN

The question of identifying the type of oil in exploitation of engine room is associated with both the quality of ship consumables (fuels and lubricants) and the composition and origin of oil in settling tanks or in dumping water. Related issue is the possibility of determining the origin of oil, which is detected in the marine environment. The key question is how oils vary in their ability to fluorescence, understood as the shapes of fluorescence spectra obtained for different wavelengths of light exciting fluorescence. In this paper we present spectra of fluorescence for six chosen oils. Those oils were previously dispersed (emulsified) in the seawater, then extracted into hexane. Fluorescence spectra were obtained using fluorescence spectrometer Perkin Elmer LS55, for excitation wavelengths in the range from 240 nm to 500 nm, and emission wavelengths from 300 nm to 790 nm. In this paper there is shown that in general both total intensity of fluorescence and shapes of spectra of fluorescence depend on the excitation wavelength and are differ for various kinds of oil. In order to visually show the differences in fluorescence abilities of various oils, the results of measurement were placed on a chart of fluorescence intensities in the function of both variables: the excitation wavelength and the emission wavelength (so called the total fluorescence spectra). Analyses of results of the described studies confirm that the different oils fluoresce differently and identification of type of oil is possible by fluorescence spectrophotometry.

2

Spectral properties of naphthalimide dyes mixed with 4-heptyl-4'-cyanobiphenyl (7CB) in Langmuir-Blodgett films

Bielejewska N., Chrzumnicka E., Stolarski R., Bauman D.

Opto-Electronics Review

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2010

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Vol. 18, No. 2

197-207

EN

Langmuir-Blodgett (LB) films formed of some fluorescent dyes, namely derivatives of 4-aminonaphthalimide, and their binary mixtures with the liquid crystal 4-heptyl-4'-cyanobiphenyl (7CB) have been studied. The electronic absorption and fluorescence spectra were recorded. On the basis of these spectra, the spectral properties of the dyes and the intermolecular interactions in ultrathin ordered films were determined. The conclusions about the tendency to the creation of aggregates by dye molecules in LB films have been drawn. The measurements of absorption by using linearly polarised light have allowed us to determine the arrangement of the dye and liquid crystal molecules on the air-solid substrate interface.

3

Synthesis, Crystal Structure, Characterization and Ab Initio Calculations on a Dicycle Pyrazoline Derivative

Guo H. M., Zhang J., Zhao P. S., Jian F. F.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 2

263-274

EN

A dicycle pyrazoline derivative, 1-acetyl-5-(2-chlorophenyl)-3,4-(a-o-chlorotolylene-cyclohexano) pyrazoline, was synthesized and characterized by elemental analysis, IR, UV-Vis, fluorescence spectra and X-ray single crystal diffraction. Quantum chemical calculations were performed by using B3LYP and HF methods with 6-311G* basis set. Both methods can well simulate the molecular structure. Vibrational frequencies were predicted, assigned and compared with the experimental values, which suggest that both methods can only approximatively predict the vibrational frequencies. Electronic absorption spectra predicted by B3LYP/6-311G asterisk operator method well corresponding with the experimental data and natural bond orbital analyses indicate that the absorption bands are mainly derived from the contribution of n → pi asterisk operator and pi → pi asterisk operator transitions. For the system studied here, HF/6-311G asterisk operator method cannot be used to obtain the electronic absorption spectra. On the basis of vibrational analysis, the thermodynamic properties of the title compound at different temperature have been calculated, revealing the correlations between C0 p,m S 0 m, H0 m and temperature.

4

Structural Elucidation, Optical and Magnetic Properties of Tetraphenylborate Salt of 2,5-[1-Methyl-4-[2-(4-hydroxyphenyl)ethenyl)]pyridinium]-butane

Stoyanov S., Koleva B. B., Kolev T., Petkov I., Spiteller M.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 11

2167-2178

EN

Structure, magnetic and optical properties of tetraphenylborate salt of 2,5-[1-methyl-4-[2-(4-hydroxyphenyl)ethenyl)]pyridinium]-hexane were performed for condensed phase by means of solution and solid-state conventional and linear-polarized IR-spectroscopy of oriented colloids in nematic host, UV-Vis and fluorescence methods, HPLC MS-MS tandem and ESI mass spectrometry, 1H-, 13C- and 1H-1H COSY NMR, TGV and DSC methods. Electronic structure and vibrational analysis were carried out by quantum chemical calculations at two levels of theory second-order Moller-Plesset perturbation theory (MP2) and density functional theory (DFT) using 6-31G* basis set. B3LYP method, which combines Becke's three-parameter non-local exchange functional with the correlation function of Lee, Yang and Parr, was applied.

5

Spectroscopy of Cd2 and Zn2 molecules in free-jet supersonic beams: experimental and theoretical studies

Ruszczak M, Strojecki M, Krośnicki M, Łukomski M, Koperski J

Optica Applicata

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2006

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Vol. 36, nr 4

s. 451--459

EN

A method of supersonic beam combined with techniques of laser spectroscopy and simulations of spectra were employed to study interatomic potentials of Cd2 and Zn2 molecules. Total laser induced fluorescence was recorded after an excitation of Cd2 using laser radiation in the range of 2200–2260 Å. The observed structures are interpreted as due to the transitions from υ" = 0 in the ground state to vibrational levels below the potential barrier of the 11u(51P1) electronic state. Studies of Zn2 consisted of simulations of excitation and fluorescence spectra recorded at the transition. In the simulations, both isotopic and rotational structures were taken into account.

6

Spectroscopic and Thermal Studies of Magnesium(II), Barium(II), Zinc(II), Copper(II), Lanthanum(III) and Aluminium(III) Comlexes with 3-Phenyl-1-methylpyrazolo[3,4-b}quinolino-6-carboxylic Acid

Kowalczyk B., Brągiel P., Kapuśniak J., Giełzak-Koćwin K., Tsvirko M., Siemion P., Jarosz B.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 11

1721-1730

EN

Magnesium(II), barium(II), zinc(II), copper(II), lanthanum(III) and aluminium(III) complexes with 3-phenyl-1-methylpyrazolo[3,4-b]quinlino-6-carboxylic acid (HPQ) were stud ied by IR and EPR methods, TG-DSC ther mal analysis, powder X-ray method, absorption and fluorescence spectroscopy. The IR spectra suggest that the carboxylate ligand acts as mono- or bidentate species. EPR spectra indi ate the dimerization of copper(II) complex. During thermal decomposition the hy drated complexes lose all the crystallization and coordination water molecules and decompose gradually to oxides, and to BaCO3 in the case of barium(II) complex. The powder fluorescence spectra in dicated the differences in emission of ligand and zinc(II), magnesium(II), aluminium(III) and copper(II) complexes.