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A Capacitive Detector for Determination of Organic Solvents in Water Solutions - the Effect of Inorganic Electrolytes.
Fišarová, Michaela ; Opekar, František (advisor) ; Štulík, Karel (referee)
The effect of inorganic electrolytes on the determination of relative permittivity and concentration of water solutions of 1,4 dioxane was studied in this work. The method used was dielectrimetry, and NaCl, KCl, CsCl and LiCl at various concentrations were tested electrolytes. The interfering effect of these electrolytes was found for concentrations above 0.05 mmol l-1. It was also found that the interfering factor is purely the solution conductivity independent on the ion kind. The measurements were carried out with both the planar and the tubular detection cell having the electrodes insulated from the solution. The cell was connected to the differentiator (the voltage is the analytical signal) or multivibrator (the frequency is the analytical signal). A good agreement between experimental results and the modeled calculation for the detector with differentiator was also obtained.
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Determination of ethanol in petrol using impedance detector
Kadlecová, Tereza ; Opekar, František (advisor) ; Štulík, Karel (referee)
This work deals with the determination of ethanol in petrol using contactless impedance detector. Planar and tubular detection cells of various geometric parameters are tested. The cells are connected as a frequency determining capacitor in an integrated multivibrator circuit. Analyzed gasoline, whose dielectric constant depends on the ethanol content, forms the dieletric of the capacity cells. Therefore, for various contents of ethanol, the capacity of the detection cells varies and the multivibrator generates different frequency. Based on the calibration, the content of ethanol can be determined from the frequency measured. The results obtained are compared with those obtained by gas chromatography with mass spectrometric detection.
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Analysis of pigments and binders in colour layer of art works
Kučková, Štěpánka ; Pacáková, Věra (advisor) ; Štulík, Karel (referee) ; Kopecká, Ivana (referee) ; Novotná, Miroslava (referee)
4. Conclusions 1. The method of gas chromatography was successfully optimised for a reliabie oeteňation of individual components in coiophony and Mexioan coPai' ificant 2. of arl the stu<iied pigments, verdigris exhibits the most stgn effect on the composition of fresh corophony and Mexican copal' 3. The degradative processes caused by aftif,rcial ageing of diterpenoids (pimaradiene tolttul"' and abietadiene acids) in colophony and triterpenoids (ct- and B-amyrin) in Mexican copal were detected' ___________ i I -. l i3 c:oriern oť u]tramícrotom. ,,.^'::..:. distonion can be solved by the use oť compare tt," int.u.i A more convenienl reÍlection ...nn,o,..o spectra ", ;;;": J:ffi: ";J-",,;,J.5. The detection iimit corour rayers ,.. Jt ".t infrared spectroscopy for the non-aged moder (*zw) forprussian :',t'' n (w/w) for c6pp1 rimits were rouna Tand0'3-1 "@;;;;: phthalocvanine' 1-3 %o phtharocyanin " r, n'l'.the artinciatl;' ;JTil:t:Jffi:: ó. MALDI.T.F MS is w/w) and indigo (3.l0 % wlw). in fresh and artificial able to ídentify indigo ar are 0.01 o/o lv/wÍ.b. i".: aged model cil;, copper phthalocyanine 7. MALDI-T.. ,, ,o,tt*o and 0'03 n *,* ^i,""' The detection limits their morecurar ions. :ntifies carmine, tu..ui. ropper phthalocyanine' associatedproreins. In addition' t"*;;:1""::"::ff:;;'Jl 8. The technique...
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Determination of ethanol in petrol using impedance detector
Kadlecová, Tereza ; Opekar, František (advisor) ; Štulík, Karel (referee)
This work deals with the determination of ethanol in petrol using contactless impedance detector. Planar and tubular detection cells of various geometric parameters are tested. The cells are connected as a frequency determining capacitor in an integrated multivibrator circuit. Analyzed gasoline, whose dielectric constant depends on the ethanol content, forms the dieletric of the capacity cells. Therefore, for various contents of ethanol, the capacity of the detection cells varies and the multivibrator generates different frequency. Based on the calibration, the content of ethanol can be determined from the frequency measured. The results obtained are compared with those obtained by gas chromatography with mass spectrometric detection.
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Impedimetric contactless detection of compounds in gas phase
Pavlíček, Václav ; Opekar, František (advisor) ; Štulík, Karel (referee)
Simple and sensitive detector based on contactless impedance detection has been tested. The detection cell consists of two insulated wire electrodes placed in a PTFE tube through which the test vapour phase flows. It has been found that the detector is sufficiently sensitive and reliable for determinations of common concentrations of water vapour in the air. Qualitative tests indicate that the vapour of organic solvents can also be monitored. This is the first application of contactless impedance detection of compounds in the gaseous phase based on a new instrumental approach to impedance detection. Keywords: Impedance detection, Contactless impedance detector, Vapour phase, Relative humidity, Organic solvent vapour
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Development and Application of High Performance Separation Methods in Connective Tissue Analysis
Braun, Martin ; Štulík, Karel (advisor) ; Pacáková, Věra (referee) ; Samcová, Eva (referee)
24 Annotation: This work is concerned with the development and application of high performance separation methods suitable for determination of clinically considerable fragments of collagen and elastin as the most important proteins of connective tissues. For their analyses, various chromatographic and electrophoretic methods have been used, including high performance liquid chromatography (HPLC), capillary zone electrophoresis (CZE) and micellar electrokinetic capillary chromatography (MEKC). This work has aimed at optimization of the developed and modified analytical separation procedures and methods and their utilization for determination of clinically important markers of connective tissue degradation. The key validation parameters of the analytical methods used in this work were evaluated too, which enabled their comparison with other approaches. One of the most important results of this work is thus high sensitivity, precision, repeatability and robustness of the methods which was found in a number of biological sample types. Successful was also very good HPLC separation of the analyzed cross-links in both collagen and elastin tissues. High performance methods are described which have been suggested and optimized for separation and quantitative determination of pentosidine, pyridinolines and...
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