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Study of links between biogenic VOC emissions and concentration of tropospheric ozone
Zemánková, Kateřina
Title of dissertation: Study of links between biogenic VOC emissions and concentration of tropospheric ozone Kateřina Zemánková, 2010 Dissertation directed by: doc. RNDr. Josef Brechler, CSc. Dept. of Meteorology and Environment Protection, Faculty of Mathematics and Physics, Charles University in Prague Presented work focuses on influence of volatile organic compounds from biogenic sources on concentration of tropospheric ozone. Volatile organic compounds (VOC) play an important role in the tropospheric chemical system. Together with oxides of nitrogen they form two major components of reactions leading to low-level ozone formation. Volatile organic compounds are emitted into the atmosphere from an- thropogenic as well as from biogenic sources. In global, VOCs from natural sources are approximately ten times higher in magnitude than those of anthropogenic origin. Biogenic VOCs are emitted from various sources among which the forest ecosystems predominate. Group of VOCs of natural origin comprises wide range of chemical com- pounds. Those emitted in highest concentrations are isoprene and group of monoter- penes. Emissions of biogenic VOCs from the area of the Czech Republic have been es- timated based on the high resolution land cover data giving detailed information of sigle tree species...
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Virulence factors of the Trichophyton benhamiae complex
Machová, Lenka ; Čmoková, Adéla (advisor) ; Labuda, Roman (referee)
Dermatophytes are a group of fungi, some of which can cause skin diseases in humans and animals due to their ability to degrade keratinized tissue. Representatives of this group also include strains from the Trichophyton benhamiae complex, known to cause dermatophytosis especially of small rodents and rabbits. In the last decade, one of four populations of this complex has spread epidemically across Europe among guinea pigs and their breeders. To answer the question what stands behind the successful spread of this population, the gene expression and production of volatile organic compounds of epidemic and non-epidemic populations of T. benhamiae was investigated. Gene expression of three strains from each population was studied during growth in liquid medium and on ex vivo mouse skin models prepared according to a newly optimized protocol. RNAseq and RT-qPCR methods were chosen for the gene expression analysis. Based on the literature and the results of RNAseq preliminary analysis, several genes were selected for which specific primers were designed. The spectra of the produced volatile organic compounds of the same strains growing on sheep wool in vials were analyzed by GC-MS. While non-epidemic populations did not differ in gene expression and production of volatile organic compounds, the...
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Klasifikace korozního poškození historického olova a systém prostředků pro jeho konzervaci
Kouřil, Milan ; Ďurovič, Michal ; Bartl, Benjamin ; Strachotová, Kristýna Charlotte ; Msallamová, Šárka
Mnohé muzejní a archivní instituce se v současnosti potkávají s problematikou koroze olověných sbírkových předmětů, uložených v depozitářích, způsobenou citlivostí olova vůči těkavým organickým sloučeninám (VOC), zejména vůči kyselině octové. Zvláštní skupinou těchto olověných předmětů jsou olověné buly (kovové pečeti), které bývají obvykle připojeny k pergamenovým listinám pomocí textilního závěsného materiálu. Metodika zavádí systém kategorizace korozního poškození olověných pečetí a hodnocení podmínek jejich uložení a navrhuje postupy konzervačních opatření vhodné pro možné varianty výsledky průzkumu stavu pečetí a expozičních podmínek. Navržené konzervační postupy jsou založeny především na eliminaci agresivních složek prostředí volbou vhodných obalových materiálů a použitím sorbentů.
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Analysis of volatile organic compounds produced by monocytes during sepsis
Bártová, Adéla ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This thesis is focused on the possibility of analysis of volatile organic compounds produced by monocytes during sepsis. Method of comprehensive two-dimensional gas chromatography with mass spectrometric detection was chosen for this purpose. Content of the first part was the optimization of the method of two-dimensional gas chromatography for the determination of volatile organic compounds. In this part were gradually adjusted parameters of the gas chromatography method to achieve the maximum efficiency. Further were adjusted conditions of samples preparation. Content of the second part was the usage of already optimized method for the analysis of the samples set of monocytes. Samples were subjected to the action of different inhibitors of the immune system and stimulators simulating bacterial or yeast infection. Based on this analysis were identified some compounds, which are produced by monocytes under condition simulating the infection.
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Pressure loss of catalyst carriers
Linda, Matúš ; Kilkovský, Bohuslav (referee) ; Jecha, David (advisor)
The diploma thesis is divided into four main parts. The first part deals with the issue of waste management and its energy utilization in waste incineration. Processed harmful substances produced by incineration as well as emission limits. It deals with the types of catalytic carriers, their description, production and more detailed processing of ceramic foam VUKOPOR. The second part is devoted to technologies utilizing catalytic processes and a more detailed specification of the process. In the third part there is processed the calculation methods for pressure losses for individual types of carriers. Fourth, the most extensive part describes the INTEQII experimental device, its technology and construction, as well as the principle of the practical part, measuring of the pressure losses of carriers. It includes the evaluation of pressure losses in separate categories of carriers, such as the bed, HoneyComb and VUKOPOR ceramic foam. Subsequently, a comparison of the pressure losses of all carriers is made relative to the reference size of 1 m. The impact of bonding of VUKOPOR foam samples on the size of pressure losses is discussed. At the end of this section, the suitability of calculation methods for individual carriers is evaluated, depending on the experimental pressure loss data.
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Ion processes in gases for the trace analysis of volatile compounds in air
Spesyvyi, Anatolii ; Španěl, Patrik (advisor) ; Matejčík, Štefan (referee) ; Tichý, Milan (referee)
This thesis describes development of the new selected ion flow-drift tube mass spectrometry technique, SIFDT-MS, for online quantification of volatile organic compounds, VOCs, based on gas phase ion-molecule reactions. SIFDT-MS represents a new generation of the successfully used selected ion flow tube, SIFT- MS, analytical method. The essential extension of SIFDT-MS is the uniform electric field E applied across the flow tube reactor, thus converting it to the flow-drift tube where the ion processes can be governed by strength of field E. Newly introduces Hadamard modulation of the gate lens before the flow-drift tube enables direct ion residence, and correspondently ion-molecule reaction, time measurement that is necessary for the precise concentration calculations under variable conditions. The detailed experimental study of these processes results was carried out to form a basis of the analytical method. In order to overcome a well-known issue of SIFT-MS, when mass spectral peaks of isobaric ions overlap, the pseudoinverse matrix multiplication for isobaric mixtures was demonstrated. Finally two data mining approaches were successfully tested on the data of the fragmentation signals of seven monoterpene isomers obtained in SIFT-MS.
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Identification and quantification of biomarkers of gastrointestinal diseases using mass spectrometry
Pospíšilová, Veronika ; Španěl, Patrik (advisor) ; Jelínek, Ivan (referee)
6 Abstract This thesis focuses on the identification and quantification of volatile metabolites in the exhaled breath that might be used as possible biomarkers of Gastroesophageal Reflux Disease. Animal tissue samples were exposed to conditions simulating the gastric environment to identify specific volatile compounds that would be chosen for real-time quantification in exhaled breath of GERD patients and healthy controls using selected ion flow tube mass spectrometry. Solid phase microextraction, was used in combination with gas chromatography mass spectrometry, for qualitative analyses of the headspace of these samples. Only acetic acid was significantly elevated and so it has been elected for the quantitative analysis in the breath of the patients. The median concentration of acetic acid measured by SIFT-MS in the exhaled breath of twenty-two GERD patients was found to be higher (85 ppbv) in comparison to the control group (31 ppbv). The results show that breath acetic acid could be valuable marker for GERD diagnosis and monitoring.
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Study of links between biogenic VOC emissions and concentration of tropospheric ozone
Zemánková, Kateřina
Title of dissertation: Study of links between biogenic VOC emissions and concentration of tropospheric ozone Kateřina Zemánková, 2010 Dissertation directed by: doc. RNDr. Josef Brechler, CSc. Dept. of Meteorology and Environment Protection, Faculty of Mathematics and Physics, Charles University in Prague Presented work focuses on influence of volatile organic compounds from biogenic sources on concentration of tropospheric ozone. Volatile organic compounds (VOC) play an important role in the tropospheric chemical system. Together with oxides of nitrogen they form two major components of reactions leading to low-level ozone formation. Volatile organic compounds are emitted into the atmosphere from an- thropogenic as well as from biogenic sources. In global, VOCs from natural sources are approximately ten times higher in magnitude than those of anthropogenic origin. Biogenic VOCs are emitted from various sources among which the forest ecosystems predominate. Group of VOCs of natural origin comprises wide range of chemical com- pounds. Those emitted in highest concentrations are isoprene and group of monoter- penes. Emissions of biogenic VOCs from the area of the Czech Republic have been es- timated based on the high resolution land cover data giving detailed information of sigle tree species...
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Study of links between biogenic VOC emissions and concentration of tropospheric ozone
Zemánková, Kateřina ; Brechler, Josef (advisor) ; Bednář, Jan (referee) ; Braniš, Martin (referee)
Title of dissertation: Study of links between biogenic VOC emissions and concentration of tropospheric ozone Kateřina Zemánková, 2010 Dissertation directed by: doc. RNDr. Josef Brechler, CSc. Dept. of Meteorology and Environment Protection, Faculty of Mathematics and Physics, Charles University in Prague Presented work focuses on influence of volatile organic compounds from biogenic sources on concentration of tropospheric ozone. Volatile organic compounds (VOC) play an important role in the tropospheric chemical system. Together with oxides of nitrogen they form two major components of reactions leading to low-level ozone formation. Volatile organic compounds are emitted into the atmosphere from an- thropogenic as well as from biogenic sources. In global, VOCs from natural sources are approximately ten times higher in magnitude than those of anthropogenic origin. Biogenic VOCs are emitted from various sources among which the forest ecosystems predominate. Group of VOCs of natural origin comprises wide range of chemical com- pounds. Those emitted in highest concentrations are isoprene and group of monoter- penes. Emissions of biogenic VOCs from the area of the Czech Republic have been es- timated based on the high resolution land cover data giving detailed information of sigle tree species...
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