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Study of H3+ recombination in selected quantum states
Varju, Jozef ; Glosík, Juraj (advisor) ; Votava, Ondřej (referee) ; Novotný, Oldřich (referee)
Title: Study of H3 + recombination in selected quantum states Author: Jozef Varju Department : Department of Surface and Plasma Science Supervisor of the doctoral thesis: Prof. RNDr. Juraj Glosík, DrSc., Department of Surface and Plasma Science Abstract: In this work measurement of the effective recombination rate coefficient of H3 + dominated and recombination governed afterglow plasma at 77 K and 145 K are presented. Population of para-H3 + in the studied plasma has been varied by using para enriched H2 as a precursor along with normal H2. Time resolved NIR-CRDS was used to in-situ measure the number density evolution of the two lowest rotational states of H3 + . Measurements at different para to ortho H3 + ratios, at otherwise identical conditions, allowed for extrapolation of the effective recombination rate coefficient of pure para-H3 + and ortho-H3 + . From measured dependences on the buffer gas densities the values of the recombination rate coefficients for the binary and ternary channel are determined of para-H3 + and ortho-H3 + . Keywords: recombination, spectroscopy, H3 + , para H2
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Radicals formation in supersonic plasma jet
Mašát, Milan ; Tichý, Milan (advisor) ; Glosík, Juraj (referee)
Title: Creation of radicals in electric discharge supersonic plasma jet Author: Milan MaSat Department: Department of Surface and Plasma Science Supervisor: Prof. RNDr. Milan Tichy, DrSc. Supervisor's e-mail address: Milan.Tichy@mff.cuni.cz Abstract: Free radicals are the key intermediates and propagators of chemical reactions in Earth's atmosphere. Study of their structure and chemical properties is vital for understanding the processes in atmosphere. But their high reactivity brings the need for specific research methods. In-situ preparation and non-invasive detection and characterization techniques are needed. Most commonly used laboratory techniques such as photodissociation or electric discharge generate radicals at temperatures that are significantly higher then those under atmospheric conditions, which we intendto model. In this work, I was developing a source of cold radicals and experimental techniques for measuring their properties. 1 combined plasma source, which creates sufficient concentrations of radicals with supersonic expansion in which the translational and internal degrees of freedom are cooled deeply below the room temperature. For their characterization I used high-resolution spectroscopy utilizing near infrared laser diodes. I also developed and built electronic circuits and software...
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Ion trap
Hejduk, Michal ; Glosík, Juraj (advisor) ; Poterya, Viktoriya (referee)
In the thesis, elementary problems observable in a temperature variable linear multipole trap are described. Those elementary processes that are important for low-temperature interstellar plasma are briefly summarized in the first part. In the same chapter, a theory about particles-confinement in a Paul trap is shortly explained as well. In the second part of the work, the Atomic Beam 22-Pole Trap experimental apparatus from the Physical Institute of the Nature Science Faculty of the Technical University in Chemnitz is described. In the last section, first measurements using the mentioned apparatus are described and interpreted.
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Rekombinace a reakce iontů v plazmatu
Varju, Jozef ; Glosík, Juraj (advisor) ; Kaňka, Adolf (referee)
One of the most interesting questions in contemporary interstellar chemistry is the HCN/HNC abundance ratio observed in dense interstellar clouds. The observed ratios vary from 80:1 to 1:5 depending on the object under observation. These ratios represent a striking deviation from thermochemical equilibrium. Dissociative recombination of HCNH+ has been invoked to explain these observations. It is suggested to study details of this recombination using FALP apparatus equipped with NIR Cavity Ringdown Absorption Spectrometer (IR - CRDS). In the presented work we have developed kinetic model describing formation of HCNH+/e- plasma and consequent production of HCN and HNC. Analysed and discussed are conditions of experiment and applicability of IR - CRDS for the proposed study. To confirm our analyses the preliminary experiments were carried out using microwave discharge cell equipped with IR - CRDS. Studies of H3O+ and H2D+ ions were carried out to put together the experiment. The absorption spectra in a plasma containing He/N2/CH4 were measured in order to determine transition frequencies for study of products of recombination of CNH+ ions.
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