Plasma Heat Flux to Solid Structures in Tokamaks Petr Vondráček Energy and particle exhaust is the key issue for future fusion reactors based on magnetic plasma confinement, namely for tokamaks. Good understanding of processes controlling plasma heat fluxes impinging the first wall of tokamaks is of a main concern for fusion research. This doctoral thesis is focused on experimental investigation of plasma heat fluxes in different locations of the COMPASS tokamak. A new infrared thermography system was built for this purpose as a part of this PhD research. There are four main topics studied using the system. First of all, a narrow near-SOL heat flux channel with a very steep radial profile is characterised in HFS limited discharges. It is shown that the near-SOL heat flux decay length is consistent with the drift-based model of the SOL heat transport. Secondly, heat loading of leading edges of misaligned limiters is broadly studied. The optical approximation of the heat flux distribution around a poloidal leading edge is confirmed as a valid approach. Heat loading of a magnetically shadowed side of a toroidal limiter gap is observed experimentally for the first time confirming predictions of particle-in-cell code simulations. Thirdly, localised hot-spots caused by the impact of runaway electrons as well as...

Electron-ion recombination and ion-neutral interactions play a piv- otal role in the chemical evolution of molecules in the Interstellar Medium (ISM). Physical conditions under which these processes un- dergo in the ISM include a wide range of temperatures and particle number densities. This work contributes to the experimental study of named low temperature phenomena in the range of 30 K to 300 K focusing on the reactions of hydrogen-containing light molecules. The employed experimental techniques are based on a combination of a Stationary Afterglow (SA) instrument with a Continuous Wave Cavity Ring-down Spectrometer (cw-CRDS). The main contributions of this work can be split into three topics. (1) The proton and deuteron con- taining isotopic system of H3 + ions. The isotopic fractionation process in collisions with hydrogen and deuterium gas was investigated in low temperature discharges, nominal ion temperatures of 80 K to 140 K, to deduce relative ion densities in the experiments. These are necessary for afterglow studies of isotopic effects in electron-ion recombination of the studied ions. (2) Vibrational spectroscopy of N2H+ ions focusing on first overtone (2ν1 band) transitions and ion thermometry, the first step towards studies of electron-ion recombination. (3) The role of para/ortho spin...

Study of plasma in the mixtures with molecular gas at wide pressure range Matěj Jan Morávek Abstract: The positive column of DC glow discharge sustained in oxygen and oxygen-nitrogen mixtures has been studied in two discharge tubes of the same shape made from different materials (Silica and Pyrex glass) for total pressures 650 - 2000 Pa and discharge currents up to 40 mA. Various parameters of the discharge - axial electric field strength, concentration of electrons and emission spectra - were studied with emphasis placed on transition region between low- and high-gradient form of the positive column. We have focused on the qualitative and quantitative analysis of the differences in emission spectra for both particular forms and the transitional region between them. The impact of 1 % admixture of nitrogen was also studied.

Inhibin A and B participate to regulation of gametogenesis. We investigated their applicability as a marker of gametogenesis of men fertility disorders. We monitored the levels of inhibins during the treatment. We interested in their paracrine activity, relationship in sera, follicular fluid and seminal plasma depending on cause of fertility failure. We studied the levels of inhibin B in serum and seminal plasma from 355 men treated for fertility failure, in the context of their andrological and immunological findings (quality of spermiogrammes and acrosome area). We monitored concentration of levels of inhibin A and B in serum and follicular fluids depending on cause of fertility failure, on course and treatment outcome. We took blood samples in the time of the oocytes collection, of the embryotransfer and early pregnancy. The follicular fluids were obtained during the oocytes collection. The levels of both of inhibins were measured by ELISA in all medium (serum, follicular fluid, seminal plasma). We confirm, that inhibin B is useful marker of spermatogenesis in men, but is necessary to examine patient in complex with determination of immunology profile or quality of acrosome. Seminal plasma is, in some indicated cases, more suitable diagnostics material. Similarly inhibin B in women seems to be...

The dissertation is focused on the findings, whether it is combination of physical and biological seed treatment for selected field crops (oilseed rape, spring barley) comparable with chemical treatment. Evaluated the effectiveness of the physical seed treatment, low temperature plasma (Gliding Arc, microwave), a biological treatment culture mycoparasitic of the fungus Trichoderma virens and culture entomopathogenic fungus Metarhizium anisopliae. In the context of experiments in laboratory conditions, was evaluated the effect of treatment on the evolution grains (the seeds), the percentage of germination grains (the seeds) and the percentage of healthy grains (the seeds). Individual plasma treatment in combination with biological treatment had a significant positive effect on the germination rate of grains (the seeds).There was no negative effect of physical and biological treatments on the grains (seeds). Involved the evaluation of emergence of the treated seed in laboratory and field conditions. In the field conditions for the selected crops in different localities and in different years, was assessed the effect of treatment on the development of the crop health and yield parameters. Plasma and plasma with T. virens treatments positively affected by the model of the plant better integration of crops, the length of the cob, (shell) and yield. The combined adjustment should in oilseed rape positive effect on the faster development of the spring, the length and strength of the root, earlier flowering and ripening. In contrast, the combined adjustment for barley spring positively influenced the emergence and tillering. According to the obtained results it seems that the combined physical and biological seed treatment is an effective alternative to the chemical treatment of seeds.

<p>Ispitivana je zavisnost brzine fronta udarnih talasa u T-cevi od vi&scaron;e parametara. Izvr&scaron;eno je povezivanje ICCD kamere sa spektrometrom. Ispitane su karakteristike celokupnog sistema i izvr&scaron;ena je njegova optimizacija i kalibracija. Izmerene su &Scaron;tarkove polu&scaron;irine 45 spektralnih linija OII, 13 spektralnih linija Si II i 14 spektralnih linija Si III. Dobijene vrednosti su upoređene sa vrednostima koje se mogu naći u literature, kao i sa teorijskim vrednostima. Urađena je detaljna analiza rezultata iz ovog rada kao i svih dostupnih prethodno dobijenih eksperimentalnih podataka.</p> / <p>The dependence of shock front velocity on different parameters was examined. The ICCD camera was mounted on the spectrometer. The characteristics of the whole system were examined and the system was optimized and calibrated. The Stark halfwidths of 45 O II spectral lines, 13 Si II spectral lines and 14 Si III spectral lines were measured. The obtained values were compared with the data available in the literature, as well as with theoretical values. A detailed analysis of both the experimental results given in this dissertation and previously published experimental data was done.</p>

Title: Laboratory study of field ion emission from dust grains Author: Martin Jeřáb Department: Department of Surface and Plasma Science Supervisor: Prof. RNDr. Jana Šafránková, DrSc., KFPP Abstract: Dust particles are common objects in space environment. As a dust particles, we call objects with typical sizes of several atoms up to approximately 100 µm. However, a total mass of dust particles is only about 1% of total mass of our galaxy, the presence of dust particles significantly affects environment. The most interesting is dynamics of dust particles and attached dust charging processes. The presented thesis consists of two main parts. The first part deals with the experimental study of field ion emission. Our measurements have been performed using gold and carbon spherical dust grains. It has been found that during the charging of dust particle using ion gun are the primary ions implanted under the surface of the dust particle from where they are release in the form of neutral gas. This releasing of implanted ions affects field ion emission for several hours. The second part of the thesis describes a development of new experimental apparatus determined to the study of photoemission dust charging and con- sequently to the "true" field ion emission study. Keywords: dust, dusty plasmas, charging properties, field...

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This diploma thesis deals with the ongoing research under the auspices of the Department of Applied Physics and Technics Faculty of Education, University of South Bohemia in České Budějovice, in which the author of the work was actively participated. The thesis is divided into theoretical and experimental part. The theoretical part contains information from natural polymers, especially cellulose, plasma technology and infrared spectrometry. The subject of the experimental part of the thesis is research that deals with the functionalization of cellulose using a microwave plasma discharge on the apparatus CX-22. In the present research was also conducted to process optimization of functionalization with the liquid precursor hexamethyldisiloxane (HMDSO).

This thesis deals with the plasma functionalization of nanofiber materials for biomedical applications. Nanofibers of SiO2 and PCL was functionalized using a microwave plasma in order to establish amine functional groups. The work includes theoretical assumptions selection of these materials, their properties and current use with emphasis on biomedical applications. The paper also presents the theoretical foundations of plasma technology, their principles and practical applications. The experimental part of the work includes the optimization of process parameters for each nanofiber materials, review hydrophilisation surface and material degradation through SEM and private functionalization. In conclusion outlines proposals for further action beyond the experiments of this work.