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Generation of volatile species of palladium for atomic absorption spectrometry
Vyhnanovský, Jaromír ; Musil, Stanislav (advisor) ; Matoušek, Tomáš (referee)
This thesis deals with optimization of the conditions for chemical generation of volatile species of palladium in combination with atomic absorption spectrometry. The volatile species of palladium were generated in a flow injection system by the reaction of an acidified sample with the solution of sodium borohydride in the presence of reaction modifiers. A diffusion flame atomizer was used due to its high robustness. In the first part of this thesis the optimization of parameters affecting the atomization in the diffusion flame was carried out (flow rates and composition of gases, observation height). In the second part, concentrations of individual reagents used (nitric acid, sodium borohydride, Triton X-100, Antifoam B, sodium diethyldithiocarbamate) were optimized. The positive effect of the reaction modifiers was demonstrated, especially that of sodium diethyldithiocarbamate, which lead to a tenfold increase in the sensitivity. The limits of detection and limits of quantification for the wavelength 244,8 nm were 0,25 mg dm-3 and 0,67 mg dm-3, respectively. The repeatability for this method for the concentration 5 mg dm-3 was 2,8 %. Key words: palladium, chemical generation of volatile species, atomic absorption spectrometry
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Photochemical generation of volatile species of cobalt for analytical atomic spectrometry
Vyhnanovský, Jaromír ; Musil, Stanislav (advisor) ; Nováková, Eliška (referee)
This master's thesis deals with the optimization of conditions for photochemical generation of volatile species of cobalt. Volatile species of cobalt were generated in a flow injection system using a high-efficiency flow through UV generator from formic acid based medium. For detection a high-resolution continuum source atomic absorption spectrometer was used. The volatile species were atomized using a diffusion flame atomizer because of its high robustness. First the optimizations of the parameters affecting the atomization in the diffusion flame and the parameters affecting the transport of the volatile species from the UV generator into the atomizer were carried out (flow rates and composition of the gases, type of a separator, observation height). After that, the optimization of the parameters of the photochemical generation itself was carried out. These were the composition of a reaction medium (concentration of formic acid and formate, type of formate salt) and irradiation time. The possibility of generation of the volatile species from acetic acid based medium was also investigated, but no signal was observed. At chosen optimal conditions of generation the influence of potential interferents was examined, mainly from inorganic acids (HNO3 and HCl) and some transition metals (Fe, Cu and Ni)....
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Generation of volatile species of palladium for atomic absorption spectrometry
Vyhnanovský, Jaromír ; Musil, Stanislav (advisor) ; Matoušek, Tomáš (referee)
This thesis deals with optimization of the conditions for chemical generation of volatile species of palladium in combination with atomic absorption spectrometry. The volatile species of palladium were generated in a flow injection system by the reaction of an acidified sample with the solution of sodium borohydride in the presence of reaction modifiers. A diffusion flame atomizer was used due to its high robustness. In the first part of this thesis the optimization of parameters affecting the atomization in the diffusion flame was carried out (flow rates and composition of gases, observation height). In the second part, concentrations of individual reagents used (nitric acid, sodium borohydride, Triton X-100, Antifoam B, sodium diethyldithiocarbamate) were optimized. The positive effect of the reaction modifiers was demonstrated, especially that of sodium diethyldithiocarbamate, which lead to a tenfold increase in the sensitivity. The limits of detection and limits of quantification for the wavelength 244,8 nm were 0,25 mg dm-3 and 0,67 mg dm-3, respectively. The repeatability for this method for the concentration 5 mg dm-3 was 2,8 %. Key words: palladium, chemical generation of volatile species, atomic absorption spectrometry
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