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Graphite furnace atomic absorption spectroscopy (GFAAS) was applied to identification of historical pigments. The method is adapted to determine different metals, usually found in pigments. Operating conditions were optimized, such as sample drying step, pyrolysis and atomization temperatures, modifiers, and volume of sample introduced into the atomizer, to reduce interferences due to a complex sample matrix. Using the optimized method pigments in samples from the painting Coronation of the Virgin from the Church of the Shroud of the Holy Virgin in Barič were identified. The samples were analyzed also by Raman microscopy to verify the identification achieved by GFAAS. Raman microscopy confirmed the assumptionsmade based on GFAAS results. Using the two techniques a variety of pigments have been identified, such as calcite, leadwhite, goethite, hematite, ultramarine, vermilion, minium, carbon black. Based on GFAAS results the presence of azuritewas observed in the blue paint sample, although this finding was not confirmed by Raman microscopy.

The influences of the application of mono- and two-component organic modifiers on lipophilicity determination of 12 tetradentate Schiff bases by reversed-phase thin layer chromatography were investigated. The main goal is to estimate types of interaction between observed compounds and components of the applied chromatographic systems and establish some behaviour pattern in order to easier choose a combination of organic modifiers which will simulate interaction in biological systems based on the facts that the same basic intermolecular interactions are responsible for the behaviour of substances in both the biological and chromatographic system. The applied organic modifier shows the ability to modify the surface of the applied sorbent, which affects the manifestation of lipophilicity of the observed compounds. Mono-component organic modifiers from different groups of the Snyder triangle were used, as well as their two-component mixtures. In addition, we compared experimentally determined calculated parameters of lipophilicity.

Graphite furnace atomic absorption spectroscopy (GFAAS) was applied to identification of historical pigments. The method is adapted to determine different metals, usually found in pigments. Operating conditions were optimized, such as sample drying step, pyrolysis and atomization temperatures, modifiers, and volume of sample introduced into the atomizer, to reduce interferences due to a complex sample matrix. Using the optimized method pigments in samples from the painting Coronation of the Virgin from the Church of the Shroud of the Holy Virgin in Barič were identified. The samples were analyzed also by Raman microscopy to verify the identification achieved by GFAAS. Raman microscopy confirmed the assumptionsmade based on GFAAS results. Using the two techniques a variety of pigments have been identified, such as calcite, leadwhite, goethite, hematite, ultramarine, vermilion, minium, carbon black. Based on GFAAS results the presence of azuritewas observed in the blue paint sample, although this finding was not confirmed by Raman microscopy.

The influences of the application of mono- and two-component organic modifiers on lipophilicity determination of 12 tetradentate Schiff bases by reversed-phase thin layer chromatography were investigated. The main goal is to estimate types of interaction between observed compounds and components of the applied chromatographic systems and establish some behaviour pattern in order to easier choose a combination of organic modifiers which will simulate interaction in biological systems based on the facts that the same basic intermolecular interactions are responsible for the behaviour of substances in both the biological and chromatographic system. The applied organic modifier shows the ability to modify the surface of the applied sorbent, which affects the manifestation of lipophilicity of the observed compounds. Mono-component organic modifiers from different groups of the Snyder triangle were used, as well as their two-component mixtures. In addition, we compared experimentally determined calculated parameters of lipophilicity.

This work investigates the adsorption mechanism of alachlor and pentachlorobenzene on chars (hydrochars and biochars) originated from Miscanthus giganteus and sugar beet shreds. Two different processes were used: hydrothermal conversion at three temperatures (180, 200, and 220 °C) and slow pyrolysis at 400 °C. Specific surface area (SSA) for all investigated chars ranged 3.87–260 m2/g, whereby biochars had a higher SSA. For hydrochars from sugar beet shreds, both the SSA (3.87–5.53 m2/g) and pore volume (0.023–0.0277 cm3/g) increased with increasing temperature, while the opposite trend was observed for hydrochars from miscanthus. The opposite trend could be a consequence of the different chemical composition of the used feedstock such as hemicelluloses and cellulose which can produce volatile organic products at higher temperatures and may cause the reduction of SSA. All adsorption isotherms were well described by the Freundlich model. The nonlinearity of the isotherms ranged from 0.450 to 0.986. Kd values for both investigated compounds followed the order: hydrochars from sugar beet shred < hydrochars from miscanthus < biochars, implying that the SSA of the chars affects the adsorption mechanism. In general, all the investigated adsorbents demonstrated higher adsorption affinity for pentachlorobenzene in comparison with alachlor, implying that hydrophobic interactions enhanced the adsorption of the more hydrophobic organic compound. In addition, for all hydrochars, adsorption affinities for the smaller pentachlorobenzene are significantly greater than for the larger alachlor, probably due to its ability to better penetrate into the pores of the adsorbents. This type of research is necessary to obtain safe adsorbents for water remediation.

The influences of the application of mono- and two-component organic modifiers on lipophilicity determination of 12 tetradentate Schiff bases by reversed-phase thin layer chromatography were investigated. The main goal is to estimate types of interaction between observed compounds and components of the applied chromatographic systems and establish some behaviour pattern in order to easier choose a combination of organic modifiers which will simulate interaction in biological systems based on the facts that the same basic intermolecular interactions are responsible for the behaviour of substances in both the biological and chromatographic system. The applied organic modifier shows the ability to modify the surface of the applied sorbent, which affects the manifestation of lipophilicity of the observed compounds. Mono-component organic modifiers from different groups of the Snyder triangle were used, as well as their two-component mixtures. In addition, we compared experimentally determined calculated parameters of lipophilicity.