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Exploration of extraterrestrial body impact and UV-driven transformation of atmospheres of terrestrial planets
Knížek, Antonín ; Ferus, Martin (advisor) ; Kabáth, Petr (referee) ; Kopecký, Vladimír (referee)
Keywords: Exoplanets, Earth, Impact, Photochemistry, Infrared Spectroscopy, Atmospheric chemistry Impacts and photochemistry are two very important driving forces for chemical transformation of planetary atmospheres. While strong UV radiation produced by young stars continuously provides a significant amount of energy, impacts are one-time events with far-reaching consequences. Especially important are then impacts on young rocky planets, including the early Earth, because these planets are likely exposed to much higher impact fluxes, commonly called 'heavy bombardment'. This bombardment is the final echo of the turbulent planetary accretion and has prominent significance for planetary environments, e.g., the chemical composition and shape of the planetary surface, the chemistry of atmospheres, aerosol production, and likely the origin of life. Future observations of exoplanets by space telescopes, such as the James Webb Space Telescope or Ariel, as well as ground-based telescopes, such as the Extremely Large Telescope currently under construction in Chile, could determine whether this heavy bombardment represents a common scenario for the evolution of terrestrial planets. Both impacts and photochemistry can be efficiently simulated and studied in laboratory conditions by state-of-the-art methods....
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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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Chemistry of Venus and EnVision mission
Kubíčková, Tereza ; Ferus, Martin (advisor) ; Kabáth, Petr (referee)
In this thesis, we summarize basic knowledge regarding chemical processes occuring in Venus atmosphere with an accent on its theoretical modelling and related spectral research. We briefly summarize objectives and technical details about scheduled ESA EnVission mission, which is supposed to widen current knowledge concerning the history, present and future of the planet and its climate, morphology, geophysics and chemical environment. The outcome of this thesis is a summary of spectral measurements of selec- ted atmospheric species using laboratory technique known as High Resolution Infrared Spectroscopy with Fourier Transform (HR-FTIR), recorded in NIR spectra of Venus with a special focus on a range of echelet spectrometer of the EnVision probe. Further in the thesis we describe a related computational atmospheric model ARGO, whose results con- cerning selected compounds are compared to in situ measurements and results of other atmospheric models. The aim of this thesis is to outline a current state of Venus research and its future related to the plan of EnVision mission and to verify functionality of current cumputational atmospheric model. 1
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Origin of biomolecules over clays under conditions of early terrestrial planets
Hrnčířová, Jana ; Ferus, Martin (advisor) ; Vaculovičová, Markéta (referee)
The mankind has always been interested in the origin of life on Earth or in the universe. The Oparin's theory1 replaced creationist metaphysical theories (of gods' actions on Earth to create life) in the beginning of the twentieth century. This theory explained production of basic building blocks of life like amino acids, nucleobases and sugars from abiogenic mixture of gases and subsequent formation of so-called coacervates. The synthesis of amino acids was then confirmed by experiments of Miller and Urey2 . Especially the theory of simple formation of nucleobases became an essential contradiction between evolutionary and molecular biologists and chemists. From biological point of view it seems very probable that primal life structures were based on the self-replicating molecule of RNA. From chemical point of view the synthesis of nucleobases seemed very problematic, therefore the models of life structures based on amino acids were favorited. This opposes the basic dogma of molecular biology, which postulates one-way transcriptions of nucleobases' sequence into amino acids' sequence exclusively. In our experiments we follow the idea of simple production of nucleobases from formamide molecule in possible primordial conditions. The mixture of formamide with different types of clays was exposed to...
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Spectral analysis of thermal decomposition of drugs and cigarette smoke
Vodenková, Eva ; Ferus, Martin (advisor) ; Nejdl, Lukáš (referee)
This bachelor thesis is focused on the spectral analysis of combustion and thermolytic products of selected addictive substances. Spectral analyzes of smoke of various tobacco products (cigarette, electronic cigarettes, hookah) were performed in order to qualitatively determine the composition of smoke and compare the harmfulness of individual types. The main objective was to determine whether the electronic cigarettes are less harmful to health in terms of the composition of the main products detectable by high-resolution spectroscopy occurring in gas-phase smoke. Furthermore, the work deals with a more detailed analysis of drug thermolysis in a wider temperature range and repeatability of measurements over a longer period of time. New spectral single crystal radiation sources from Crytur were also used to measure absorption spectra and their applicability in the field of overton spectra was tested. All these measurements were performed using Fourier transform infrared spectroscopy (FTIR). For tobacco products, less compounds were detected in electronic cigarettes and hookahs than in conventional cigarettes. In the case of drugs, we were able to confirm the repeatability of measurements and determine the percentage of individual substances at different temperatures. Furthermore, the applicability...
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The Study of Transient Species and Precursors of Biomolecules using Spectroscopic Techniques
Ferus, Martin ; Civiš, Svatopluk (advisor) ; Šponerová, Judit E. (referee) ; Wild, Jan (referee)
The presented thesis is focused on a spectroscopic study of unstable radicals, ions and molecules in a positive column glow discharge and laser plasma. The research of these fragments is supplemented by a study of biomolecules formation from these species and influence of catalysts. Molecular dynamics of radicals, ions and unstable molecules has been studied using a time resolved Fourier transform infrared spectroscopy. Time resolved spectra of CH4, HCONH2, BrCN, CH3CN, CF3Br, (CF3)2CHBr positive column glow discharges have been measured and simulated using a kinetic model including molecular dynamics, collisions and chemical and radiation transfer processes. The model has been compared with our experimental results and time resolved spectra were described in details. Fit to a complex reaction mechanism has been used to estimate a rate constant of a HCN conversion to HNC by a collision with H radical. The study of precursors of biomolecules was focused on chemical consequences of a laser induced dielectric breakdown in formamide vapor and gaseous carbon monooxide with 18 O labeled water. Dissociation products have been detected using the Fourier transform absorption spectroscopy. The experimental results have been explained by a help of a chemical laser spark dynamics model. Additionally, our the...
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Phosphine and nitrous oxide as false-positive biosignature gases in planetary spectra
Kaiserová, Tereza ; Ferus, Martin (advisor) ; Kopecký, Vladimír (referee)
5 Abstract This study is dedicated to evaluating the potential for a novel pathway of abiotic synthesis of phosphine (PH3) from phosphorus trioxide (P4O6) by a photocatalytic mechanism on aerosols. The mechanism might explain the recent possible detection of phosphine on Venus. This scenario has recently been suggested theoretically by our team based on an analogy with methane production form carbon dioxide on acidic photochemically-active surfaces of materials, which may account for a possible source of methane on Mars. Methane, just like phosphine, was suggested as an indicator of life on terrestrial planets, including Mars. The theoretical testing of photochemical phosphine generation suggests that even if this gas is present in the atmosphere of Venus it cannot be considered as an indicator of life until the suggested mechanism is excluded theoretically, or by experimental results, or direct evidence of life on Venus. This thesis will be followed by preparation of sophisticated experiments and intensive laboratory research addressing this. Furthermore, the role of nitrous oxide as another false positive biosignature was evaluated in this study. The presence of nitrous oxide can also be explained by processes other than biological, particularly on early planets. This study specifically demonstrates the...
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Consequences of heavy bombardment for chemical and prebiotic evolution on early Mars and Earth
Petera, Lukáš ; Ferus, Martin (advisor) ; Kopecký, Vladimír (referee)
The diploma thesis refers to the results of laboratory research dedicated to the influence of extraterestrial matter impacts onto a possible prebiotic synthesis on early Mars. The influence of understanding of early Mars chemistry for proceeding studies of terrestrian chemical habitus evolution and origin of life is discussed, as well as certain advantages to be made of this research within exoplanetary science. The prebiotic synthesis scenario purposed connects the hypothesis comprising a key role of extraplanetary bodies impacts played in the chemical evolution of an early Earth-like planet to the important processes studied within chemical evolution of life. Asteroid impacts are simulated by laser sparks, while post-impact thermochemical processes are mimetized in the laboratory by a controlled termolysis of certain key species in presence of meteorites, iron-rich clays and several other minerals and rocks presumably present in real impact craters. This particular field of research carried is likely to have an interesting application within current and future investigations of the Gale crater. Impactor mineraly is described on a particular example of a rare Porangaba meteorite, which, thanks to this research, has recently been addressed as a member of unique (comprising 32 bodies) family tree...
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Spectral analysis of thermal decomposition of drugs and cigarette smoke
Vodenková, Eva ; Ferus, Martin (advisor) ; Nejdl, Lukáš (referee)
This bachelor thesis is focused on the spectral analysis of combustion and thermolytic products of selected addictive substances. Spectral analyzes of smoke of various tobacco products (cigarette, electronic cigarettes, hookah) were performed in order to qualitatively determine the composition of smoke and compare the harmfulness of individual types. The main objective was to determine whether the electronic cigarettes are less harmful to health in terms of the composition of the main products detectable by high-resolution spectroscopy occurring in gas-phase smoke. Furthermore, the work deals with a more detailed analysis of drug thermolysis in a wider temperature range and repeatability of measurements over a longer period of time. New spectral single crystal radiation sources from Crytur were also used to measure absorption spectra and their applicability in the field of overton spectra was tested. All these measurements were performed using Fourier transform infrared spectroscopy (FTIR). For tobacco products, less compounds were detected in electronic cigarettes and hookahs than in conventional cigarettes. In the case of drugs, we were able to confirm the repeatability of measurements and determine the percentage of individual substances at different temperatures. Furthermore, the applicability...
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