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High energy density plasma - induced transformations of early planetary atmospheres and their impact on early global climate
Kaiserová, Tereza ; Ferus, Martin (advisor) ; Šponerová, Judit E. (referee)
The goal of this bachelor thesis is to explore one of possible solutions to faint young Sun paradox, namely greenhouse effect incurred by increased concentration of N2O induced due to high energy plasma of meteorite impact. The series of experiments were done to simulate early Earth atmosphere under the effect of impact. The results of experiments were evaluated by infrared spectroscopy. It was found that under the right circumstances, concentrations of N2O created by impacts go from 5 to 38 ppm, which is concentration high enough to resolve faint young Sun paradox. Results presented in this thesis lead us to new path of solving the faint young Sun paradox and offer many important information for prebiotic chemistry on early Earth.
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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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Analysis of solid samples using calibration free laser induced breakdown spectroscopy - application in metallurgy of meteorites
Petera, Lukáš ; Ferus, Martin (advisor) ; Krůs, Miroslav (referee)
The aim of this thesis was the development and application of the calibration-free method of the laser induced breakdown spectroscopy (LIBS). The CF-LIBS method is used to quickly analyze of sample of any size and shapes without any required surface treatment, to determinate their elemental composition. In addition, the CF algorithm is also usefull for study of atomic plasma and hot gas emision spectra to determinate their elemental composition. From this point of view, very interesting is ablation analysis of complicated matrices such as meteorites and possible comparsion with spectral analysis of meteors. In the frame of the presented bachelor thesis, was measured the ablation spectra of meteorite samples Porangaba (L4), Chellyabinsk (LL5), Northwest Africa 869 (L3-6) and Dhofar 1994 (CM2). Based on the measured spectra of these meteorites, was created an atlas of the emision lines and assigned parameters of the spectroscopic transitions of the elements, typically occuring in a meteorites. Thisatlas will also serve as the source database for automatic pragram Ablator (automatically evalueting of ablation emission spcectra) and MeteorMaster (automatic program for the interpretation of meteors spectra). The database will be used for CF-LIBS analysis of the Porangaba meteorite. The database is...
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Experimental study of chemical evolution of biomolecules under early Earth conditions
Knížek, Antonín ; Ferus, Martin (advisor) ; Adam, Vojtěch (referee)
Origin of life is a still-enduring gap in human knowledge. This work is focused on revealing of several pieces of this puzzle. State of the art scenarios of biomolecules synthesis under prebiotic conditions are presented and discussed. This thesis presents our recent experiments suggesting a novel idea that neutral planetary atmosphere containing a mixture of neutral volcanic-type gasses (CO2, N2, H2O) can be converted over acidic mineral catalysts upon irradiation by a soft UV-radiation into a relatively reactive mixture of reducing gases (CH4, CO), which can be further reprocessed by high-energy chemistry. The resulting mixture (CH4, CO + N2) represents a common reducing atmosphere related e.g. to the chemistry of Titan, the largest moon of Saturn, as well as a possible representation of the secondary atmosphere of our planet. Also, photocatalytic reduction of CO2-rich atmosphere can explain the abiotic origin of methane on current Mars or other terrestrial planets. In our subsequent experiments, corresponding equimolar model mixture of CH4 : CO : N2 in presence of water vapour was subjected to reprocessing by high-power laser plasma simulating an asteroid impact - one of a series of impact events which the young Earth experienced during the first 600 million years of her history. Upon delivery...
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High resolution infrared spectroscopy as diagnostic tool for combustion and plasma chemistry
Zelinger, Zdeněk ; Nevrlý, Václav ; Grigorová, Eva ; Bitala, P. ; Dostál, Michal ; Suchánek, Jan ; Kubát, Pavel ; Engst, Pavel ; Ferus, Martin ; Kubelík, Petr ; Civiš, Svatopluk
Monitoring of transient species within combustion experiments (laminar flames, shock-tubes, flow reactors, etc.) is still relatively challenging task especially if application of non-invasive, i.e. optical detection methods is required. High resolution infrared spectroscopy is based on observation of the fine rotation structure that accompanies vibration transitions and thus provides direct information essential to characterization of both molecular structure and reaction dynamics. Thanks to its outstanding advantage enabling unambiguous assignment of specific molecular system according to its spectral feature, it can serve as a helpful tool for exploring complex reaction mechanisms as well as chemical reactivity of individual species present in laboratory flames or plasmas.\nPrevious studies gaining new insights into combustion and plasma chemistry as well as our recent advances targeted towards application of high resolution infrared spectroscopy for species concentration measurement in laminar flames are summarized here below.
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Wavelength modulation spectroscopy for multicomponent ana-lytics of biomass burning tracers
Dostál, Michal ; Válek, V. ; Suchánek, Jan ; Kristlová, E. ; Roupcová, P. ; Zelinger, Zdeněk ; Nevrlý, Václav ; Bitala, P. ; Vašinek, M. ; Kubát, Pavel ; Ferus, Martin ; Civiš, Svatopluk
The potential of Tunable Diode Laser Absorption Spectroscopy (TDLAS) for monitoring of several species produced by biomass burning is in focus of this work. The infrared spectra of selected molecules (HCOOH, C2H2, CH3CN, N2O, CH3OH, CH3COCH3) are measured in laboratory conditions and the selectivity and of this method is demonstrated.
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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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