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Study of electrical discharge initiated chemical processes in Titan like atmosphere in stationary regime
Zbytek, Filip ; Chudják, Stanislav (referee) ; Krčma, František (advisor)
The aim of the presented bachelor's thesis was the study of chemical processes initiated by electric discharge in an atmosphere similar to that of Titan. This bachelor's thesis focuses on simulating Titan's atmosphere at normal laboratory temperature and atmospheric pressure. Titan's atmosphere is mainly composed of nitrogen, which constitutes 98 % of the atmosphere. For the simulation, spark and glow electric discharges generated in a special reactor were used. Measurements were conducted with varying CH4 flow rates of 0, 1, 2, 3, and 4 sccm. The first part of the measurements was conducted for the spark discharge and the second part for the glow discharge, both under the same conditions. The synthesized gaseous products were analyzed using proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS). Mainly simple nitrogenous aliphatic hydrocarbons were detected, but with increasing CH4 flow, the formation of more complex aromatic hydrocarbons occurred for both discharges. The composition of the plasma and its diagnostics were investigated using optical emission spectrometry (OES). Measurements using proton transfer reaction mass spectrometry and optical emission spectrometry were conducted simultaneously.
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Diagnostics of plasma generated in the atmosphere simulating Mars
Fojtíková, Nikola ; RNDr. Martin Ferus, Ph.D., (referee) ; Kozáková, Zdenka (advisor)
The aim of the diploma thesis was the diagnostics of plasma generated in the atmosphere simulating conditions on Mars. This diploma thesis is focused on the simulation of Mars’ atmosphere at atmospheric pressure and normal laboratory temperature. Due to the similar conditions of Mars' atmosphere with Earth, this planet has been explored in the past as well as up to now. Mars' atmosphere is composed mostly of carbon dioxide, which makes up more than 90 % of Mars' atmosphere. A glow discharge generated in a special reactor at atmospheric pressure at a flow of pure CO2 was used to simulate the atmosphere of Mars. Part of the measurement was performed only in pure CO2 with changing current of 20, 25, 30, 35 and 40 mA. Part of the measurements was focused on the study of the effect of the addition of various gases, such as nitrogen, hydrogen and methane, at changes in their flow rates of 1, 2, 3, 4 and 5 sccm. The products formed in the special reactor were analysed using a mass spectrometer with proton ionization and with a flight time analyser. Optical emission spectrometry was used for plasma diagnostics and composition. Mainly simple aliphatic hydrocarbons, alcohols, aldehydes, and ketones were detected. With increasing flow rates of the individual gases, more complex aromatic compounds with higher molecular weights were formed. Corresponding mass and optical emission spectra were measured simultaneously.
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Analytical methods for verifying the authenticity of the wine
Flegr, Šimon ; Štursa, Václav (referee) ; Diviš, Pavel (advisor)
This bachelor’s thesis deals with the authenticity of wine, focusing on the authenticity of geographic origin. The theoretical part of this work summarises the main components of wine and their changes during the production proces. Control techniques are introduced, including the ones used by the goverment’s control bureau (SZPI) and other documented methods. Areas recognised for growing wine are described, including the Morava area in Czechia and its imminent adjacent areas in Austria and Slovakia. Experimental part deals with the trace amount analysis of selected elements and phenolic compounds. The element analysis was conducted using mass spectrometry and optical emission spectrometry, whilst the phenolic compounds were separated using high-pressure liquid chromatography with spectrophotometric detection. The results were analysed using discrimination analysis to separate groups with different areas of origin, with the aid of data from former research.
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Study of Chemical Processes in Exoplanetary Atmospheres
Chudják, Stanislav ; doc. Mgr. Vít Kudrle,Ph.D. (referee) ; Krčma, František (advisor)
In the present work, the abnormal glow discharge at atmospheric pressure was generated in the nitrogen-methane (1 to 5 %) gaseous mixtures related to the atmosphere of Titan. The discharge itself was monitored by optical emission spectrometry that confirmed presence of active nitrogen species and various radicals formed from methane. Besides them, the CN spectral bands were observed. Intensities of all light emitting species were studied in the dependence on applied power and composition of nitrogen-methane mixture. The rotational temperature of about 2000 K was calculated from the second positive nitrogen system. The vibrational temperature also obtained from neutral nitrogen molecule increased nearly directly with methane from 3000 K (1 % CH4) to 3600 K (5 % CH4). In the contrary, vibrational temperature obtained from nitrogen molecular ion decreased with methane in the gaseous mixture and increased with applied discharge power from 3700 K to 4200 K. The same trend showed the vibrational temperature calculated from violet system of CN with value from 4600 K to 5800 K. The stable discharge products were analysed by proton transfer time of flight mass spectrometry of the exhausting gas. Presence of many aliphatic and some aromatic hydrocarbons was confirmed as well as quite a lot of amino and cyano compounds. Increasing concentrations of methane have produced more substances with higher molecular weight and less simple substances that were likely to be consumed on more complex substances. Their relative intensities were determined under the same conditions as optical emission spectra were collected.
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Comparison of organic dye decomposition in various plasma systems
Dotsenko, Anastasia ; Králová, Marcela (referee) ; Kozáková, Zdenka (advisor)
This bachelor thesis deals with the comparison of the degradation of organic dyes (namely: Saturn Red L4B (Direct Red 79) and Indigo Carmine (Acid Blue 74)) in different plasma systems and the general characteristics of the optical emission spectrometry of a microwave plasma nozzle. It briefly summarizes basic information about plasmas and the processes involved. The theoretical part focuses on basic information about plasmas and their processes, basic information about dyes and their degradation methods. Plasma contains a number of active particles such as hydroxyl radicals, nitrogen oxide radicals, excited nitrogen molecules, atomic nitrogen, argon and oxygen. All these particles, together with photons generated by the plasma, are useful in environmental applications. The experimental part focuses on treating a sample of model dyes in selected plasma systems generating plasma above the liquid surface (microwave surface wave discharge, dielectric barrier discharge with liquid electrode) or below it (plasma nozzle in liquid) and evaluating their decomposition rate. Characterization of the distribution of active particles along the plasma axis of a high frequency plasma jet in argon and determination of the conditions in the plasma with respect to the environmental applicability of the system.
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Study of Chemical Processes in Extraterrestrial Atmospheres
Chudják, Stanislav ; Ferus, Martin (referee) ; Matejčík, Štefan (referee) ; Krčma, František (advisor)
Cieľom predkladanej práce je štúdium chemických procesov v mimozemských atmosférach a syntéza organických zlúčenín vznikajúcich v elektrických výbojoch v plynnej zmesi. Táto štúdia je zameraná najmä na simuláciu atmosféry Titanu. Najčastejšie zloženie plynnej zmesi bolo metán (1-4 sccm) v 200 sccm dusíku. Prebiehali tiež merania so stopovým množstvom kyslíku a oxidu uhličitého. Okrem zloženia plynnej zmesi sa menila aj velkosť dodávaného elektrického výkonu od 2 W – 12 W. Merania prebiehali za laboratórnej teploty ale aj pri teplote kvapalného dusíka, čím sa experiment výrazne priblížil reálnym podmienkam na Titane. Identifikácia syntetizovaných plynných produktov v reaktore prebiehala väčšinou pomocou hmotnostnej spektrometrie s protónovou ionizáciou. Ďalej prebehli aj merania pomocou iónovej mobilnej spektrometrie a infračervenej spektrometrie s Fourierovou transformáciou. Samotný výboj bol charakterizovaný pomocou optickej emisnej spektrometrie, ktorá potvrdzuje prítomnosť aktívnych foriem dusíka a radikálov vznikajúcich z metánu. Okrem toho boli v nameraných spektrách identifikované aj prvý negatívny a druhý pozitívny systém dusíku a tiež fialový systém radikálu CN. Z druhého pozitívneho systému dusíka bola stanovená rotačná teplota na približnú hodnotu 2300-2400 K. Vibračná teplota bola stanovená tiež z tohto systému v závislosti na zložení plynnej zmesi od 3100-3400 K. Ďalej bola vibračná teplota vypočítaná z prvého negatívneho systému dusíka, ktorá ale s koncentráciou metánu mierne klesala a rástla s výkonom v intervale od 3950-4350 K. Veľmi podobnú závislosť mala aj vibračná teplota získaná pre fialový spektrálny systém CN, ktorej hodnota sa nachádzala v intervale od 5900 do 7700 K. Pomocou hmotnostného spektrometra s protónovou ionizáciou bolo detegovaných za laboratórnej teploty množstvo alifatických uhľovodíkov, niektoré aromatické uhľovodíky a tiež amino či kyano zlúčeniny. Najvyššie molekulové hmotnosti za laboratórnej teploty boli do 150 g.mol-1 pri čom najviac zastúpenými látkami boli kyanovodík, acetylén či acetonitril. Pri meraniach za teploty kvapalného dusíka bolo identifikovaných až 200 látok do molekulovej hmotnosti 500 g.mol-1. Aj pri meraniach za nízkej teploty boli dominantnými látkami acetonitril či diacetylene, no kyanovodík už tak dominantným nebol. Ďalej bolo v meraniach použité aj malé množstvo kyslíka, a za týchto podmienok boli významnými detegovanými látkami napr. formamid či acetón. Pri meraniach za laboratórnej aj nízkej teploty platilo, že so vzrastajúcou koncentráciou metánu vznikalo viac látok s vyššou molekulovou hmotnosťou a menej jednoduchých látok, ktoré sa pravdepodobne spotrebúvali na syntézu zložitejších látok. Rovnaká závislosť bola sledovaná aj pri narastajúcom výkone dodávanom do systému. Práca obsahuje aj merania pomocou iónovej mobilnej spektrometrie. Najvýznamnejším detegovaným plynom bol amoniak, ďalej bol detegovaný propan-2-ol, etanol a s najväčšou pravdepodobnosťou aj dietylamín. Poslednou sadou meraní boli merania pomocou FTIR, ktoré sú v zhode s výsledkami z PTR-TOF-MS. V spektre sú tiež vidieť intenzívne pásy prislúchajúce jak alifatickým uhľovodíkom (3050-2800 cm-1), tak aromatickým zlúčeninám (benzén na 1506 cm-1) a takisto aj pásy prislúchajúce dusíkom substituovaným uhľovodíkom (1350-1600 cm-1 a 3200-3400 cm-1). V spektre sú ďalej viditeľné píky HCN (713 cm-1) a C2H2 (729 cm-1), z ktorých boli zostrojené grafy závislostí na koncentrácii metánu.
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Diagnostics of plasma generated in the atmosphere simulating Mars
Fojtíková, Nikola ; RNDr. Martin Ferus, Ph.D., (referee) ; Kozáková, Zdenka (advisor)
The aim of the diploma thesis was the diagnostics of plasma generated in the atmosphere simulating conditions on Mars. This diploma thesis is focused on the simulation of Mars’ atmosphere at atmospheric pressure and normal laboratory temperature. Due to the similar conditions of Mars' atmosphere with Earth, this planet has been explored in the past as well as up to now. Mars' atmosphere is composed mostly of carbon dioxide, which makes up more than 90 % of Mars' atmosphere. A glow discharge generated in a special reactor at atmospheric pressure at a flow of pure CO2 was used to simulate the atmosphere of Mars. Part of the measurement was performed only in pure CO2 with changing current of 20, 25, 30, 35 and 40 mA. Part of the measurements was focused on the study of the effect of the addition of various gases, such as nitrogen, hydrogen and methane, at changes in their flow rates of 1, 2, 3, 4 and 5 sccm. The products formed in the special reactor were analysed using a mass spectrometer with proton ionization and with a flight time analyser. Optical emission spectrometry was used for plasma diagnostics and composition. Mainly simple aliphatic hydrocarbons, alcohols, aldehydes, and ketones were detected. With increasing flow rates of the individual gases, more complex aromatic compounds with higher molecular weights were formed. Corresponding mass and optical emission spectra were measured simultaneously.
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Multielement analysis of flue gas residues from secondary lead smelting
Šebek, Ondřej ; Mihaljevič, Martin (advisor) ; Rychlovský, Petr (referee) ; Hruška, Jakub (referee)
Multielement analysis of flue gas residues from secondary lead smelting was tested using seven decomposition methods on four different flue gas residues and certified reference materials (CRM) CPB-2 (Pb concentrate, CCRMP). The studied samples contained both silicates and also high contents of phases with Pb, primarily Pb chlorides and sulphates. Solutions prepared by various decomposition methods were analysed using ICP OES (Al, As, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Si, Sn, Sr, Ti, Tl, V, Zn). Greater yields were found for most of the elements by combined decomposition (with fusion) and decomposition by sintering. Nonetheless, both methods exhibited major losses of volatile elements (As, Bi, Sb, Tl). Thus, one of these methods must always be combined with a method of decomposition in a closed system. The work also demonstrates that, for investigation of untraditional waste geological materials (e.g. flue residues from high- temperature industrial processes), it will be necessary in the future to produce new certified reference materials with anomalous chemical and mineralogical compositions, which are not currently available on the market. Laboratory extraction tests were performed on two different types of flue residues - kinetic (30 days) with ratio L/S...
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Analytical methods for verifying the authenticity of the wine
Flegr, Šimon ; Štursa, Václav (referee) ; Diviš, Pavel (advisor)
This bachelor’s thesis deals with the authenticity of wine, focusing on the authenticity of geographic origin. The theoretical part of this work summarises the main components of wine and their changes during the production proces. Control techniques are introduced, including the ones used by the goverment’s control bureau (SZPI) and other documented methods. Areas recognised for growing wine are described, including the Morava area in Czechia and its imminent adjacent areas in Austria and Slovakia. Experimental part deals with the trace amount analysis of selected elements and phenolic compounds. The element analysis was conducted using mass spectrometry and optical emission spectrometry, whilst the phenolic compounds were separated using high-pressure liquid chromatography with spectrophotometric detection. The results were analysed using discrimination analysis to separate groups with different areas of origin, with the aid of data from former research.
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Study of Chemical Processes in Exoplanetary Atmospheres
Chudják, Stanislav ; doc. Mgr. Vít Kudrle,Ph.D. (referee) ; Krčma, František (advisor)
In the present work, the abnormal glow discharge at atmospheric pressure was generated in the nitrogen-methane (1 to 5 %) gaseous mixtures related to the atmosphere of Titan. The discharge itself was monitored by optical emission spectrometry that confirmed presence of active nitrogen species and various radicals formed from methane. Besides them, the CN spectral bands were observed. Intensities of all light emitting species were studied in the dependence on applied power and composition of nitrogen-methane mixture. The rotational temperature of about 2000 K was calculated from the second positive nitrogen system. The vibrational temperature also obtained from neutral nitrogen molecule increased nearly directly with methane from 3000 K (1 % CH4) to 3600 K (5 % CH4). In the contrary, vibrational temperature obtained from nitrogen molecular ion decreased with methane in the gaseous mixture and increased with applied discharge power from 3700 K to 4200 K. The same trend showed the vibrational temperature calculated from violet system of CN with value from 4600 K to 5800 K. The stable discharge products were analysed by proton transfer time of flight mass spectrometry of the exhausting gas. Presence of many aliphatic and some aromatic hydrocarbons was confirmed as well as quite a lot of amino and cyano compounds. Increasing concentrations of methane have produced more substances with higher molecular weight and less simple substances that were likely to be consumed on more complex substances. Their relative intensities were determined under the same conditions as optical emission spectra were collected.
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